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1Enhanced efficiency of generating induced pluripotent stem (iPS) cells from human somatic cells by a combination of six transcription factors显示文摘Jing Liao Zhao Wu Ying Wang Lu Cheng Chun Cui Yuan Gao Taotao Chen Lingjun Rao Siye Chen Nannan Jia Huiming Dai Shunmei Xin Jiuhong Kang Gang Pei Lei Xiao 2008Cell Research2008,18,5:61
2Persistence and clearance of viral RNA in 2019 novel coronavirus disease rehabilitation patients显示文摘Background:A patient’s infectivity is determined by the presence of the virus in different body fluids,secretions,and excreta.The persistence and clearance of viral RNA from different specimens of patients with 2019 novel coronavirus disease(COVID-19)remain unclear.This study analyzed the clearance time and factors influencing 2019 novel coronavirus(2019-nCoV)RNA in different samples from patients with COVID-19,providing further evidence to improve the management of patients during convalescence.Methods:The clinical data and laboratory test results of convalescent patients with COVID-19 who were admitted to from January 20,2020 to February 10,2020 were collected retrospectively.The reverse transcription polymerase chain reaction(RT-PCR)results for patients’oropharyngeal swab,stool,urine,and serum samples were collected and analyzed.Convalescent patients refer to recovered non-febrile patients without respiratory symptoms who had two successive(minimum 24 h sampling interval)negative RT-PCR results for viral RNA from oropharyngeal swabs.The effects of cluster of differentiation 4(CD4)+T lymphocytes,inflammatory indicators,and glucocorticoid treatment on viral nucleic acid clearance were analyzed.Results:In the 292 confirmed cases,66 patients recovered after treatment and were included in our study.In total,28(42.4%)women and 38 men(57.6%)with a median age of 44.0(34.0-62.0)years were analyzed.After in-hospital treatment,patients’inflammatory indicators decreased with improved clinical condition.The median time from the onset of symptoms to first negative RT-PCR results for oropharyngeal swabs in convalescent patients was 9.5(6.0-11.0)days.By February 10,2020,11 convalescent patients(16.7%)still tested positive for viral RNA from stool specimens and the other 55 patients’stool specimens were negative for 2019-nCoV following a median duration of 11.0(9.0-16.0)days after symptom onset.Among these 55 patients,43 had a longer duration until stool specimens were negative for viral RNA than for throat swabs,with a median delay of 2.0(1.0-4.0)days.Results for only four(6.9%)urine samples were positive for viral nucleic acid out of 58 cases;viral RNA was still present in three patients’urine specimens after throat swabs were negative.Using a multiple linear regression model(F=2.669,P=0.044,and adjusted R2=0.122),the analysis showed that the CD4+T lymphocyte count may help predict the duration of viral RNA detection in patients’stools(t=-2.699,P=0.010).The duration of viral RNA detection from oropharyngeal swabs and fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(15 days vs.8.0 days,respectively;t=2.550,P=0.013)and the duration of viral RNA detection in fecal samples in the glucocorticoid treatment group was longer than that in the non-glucocorticoid treatment group(20 days vs.11 days,respectively;t=4.631,P<0.001).There was no statistically significant difference in inflammatory indicators between patients with positive fecal viral RNA test results and those with negative results(P>0.05).Conclusions:In brief,as the clearance of viral RNA in patients’stools was delayed compared to that in oropharyngeal swabs,it is important to identify viral RNA in feces during convalescence.Because of the delayed clearance of viral RNA in the glucocorticoid treatment group,glucocorticoids are not recommended in the treatment of COVID-19,especially for mild disease.The duration of RNA detection may relate to host cell immunity.Yun Ling Shui-Bao Xu Yi-Xiao Lin Di Tian Zhao-Qin Zhu Fa-Hui Dai Fan Wu Zhi-Gang Song Wei Huang Jun Chen Bi-Jie Hu Sheng Wang En-Qiang Mao Lei Zhu Wen-Hong Zhang Hong-Zhou Lu 2020Chinese Medical Journal2020,,9:58
3Incidence And Mortality Trend of Cervical Cancer in 11 Cancer Registries of China显示文摘在许多国家客观,颈的癌症流行衰退了,但是变化的更少的信息在中国是可得到的。这研究试图在中国理解颈的癌症的流行病学的特征和趋势。11 张癌症注册表的方法颈的癌症数据在中国在 19882002 期间被分析。颈的癌症发生和死亡的年龄和城市 / 农村的差别和趋势被描述并且讨论。在 19882002 期间结果, 6007 发生诉讼的一个总数和颈的癌症的 3749 死亡诉讼在 11 张癌症注册表被报导。发生颈的癌症的粗略的率是 3.80/100,000,世界年龄调整了率是 2.78/100,000。在一样的时期,粗略的率是的死亡 2.37/100,000 和调整的世界年龄评价是 1.66/100,000。拒绝的发生和死亡趋势在这个时期期间被观察在象在农村区域一样城市。当由年龄组计算率时,我们发现衰退趋势为更年轻的女人仅仅为老妇人和增加的趋势,特别为在农村区域的女人。发生和死亡率为老妇人在中国在 19882002 的经期期间衰退了的结论。更年轻的女人在一样的经期期间显示出一个增加的趋势,特别为在农村区域的女人。Tac Lei Wei-min Mao Tong-hai Lei Li-qiong Dai Luo Fang Wan-qing Chen Si-wei Zhang 2011Chinese Journal of Cancer Research2011,23,1:42
4Transplantation of UC-MSCs on collagen scaffold activates follicles in dormant ovaries of POF patients with long history of infertility显示文摘Premature ovarian failure(POF) is a refractory disease for clinical treatment with the goal of restoring fertility. In this study,umbilical cord mesenchymal stem cells on a collagen scaffold(collagen/UC-MSCs) can activate primordial follicles in vitro via phosphorylation of FOXO3 a and FOXO1. Transplantation of collagen/UC-MSCs to the ovaries of POF patients rescued overall ovarian function, evidenced by elevated estradiol concentrations, improved follicular development, and increased number of antral follicles. Successful clinical pregnancy was achieved in women with POF after transplantation of collagen/UC-MSCs or UC-MSCs. In summary, collagen/UC-MSC transplantation may provide an effective treatment for POF.Lijun Ding Guijun Yan Bin Wang Lu Xu Yan Gu Tong Ru Xiaoying Cui Lei Lei Jingyu Liu Xiaoqiang Sheng Bin Wang Chunxue Zhang Yanjun Yang Ruiwei Jiang Jianjun Zhou Na Kong Feifei Lu Huaijun Zhou Yannan Zhao Bing Chen Yali Hu Jianwu Dai Haixiang Sun 2018Science China(Life Sciences)2018,61,12:43
5Transplantation of collagen scaffold with autologous bone marrow mononuclear cells promotes functional endometrium reconstruction via downregulating ΔNp63 expression in Asherman's syndrome显示文摘Asherman's syndrome(AS) is a common disease that presents endometrial regeneration disorder. However, little is known about its molecular features of this aregenerative endometrium in AS and how to reconstruct the functioning endometrium for the patients with AS. Here, we report that ΔNp63 is significantly upregulated in residual epithelial cells of the impaired endometrium in AS; the upregulated-ΔNp63 induces endometrial quiescence and alteration of stemness. Importantly, we demonstrate that engrafting high density of autologous bone marrow mononuclear cells(BMNCs) loaded in collagen scaffold onto the uterine lining of patients with AS downregulates ΔNp63 expression, reverses ΔNp63-induced pathological changes, normalizes the stemness alterations and restores endometrial regeneration. Finally, five patients achieved successful pregnancies and live births. Therefore, we conclude that ΔNp63 is a crucial therapeutic target for AS. This novel treatment significantly improves the outcome for the patients with severe AS.Guangfeng Zhao Yun Cao Xianghong Zhu Xiaoqiu Tang Lijun Ding Haixiang Sun Juan Li Xinan Li Chenyan Dai Tong Ru Hui Zhu Jingjie Lu Caimei Lin Jingmei Wang Guijun Yan Huiyan Wang Lei Wang Yimin Dai Bin Wang Ruotian Li Jianwu Dai Yan Zhou Yali Hu 2017Science China(Life Sciences)2017,60,4:39
6Reprogramming of ovine adult fibroblasts to pluripotency via drug-inducible expression of defined factors显示文摘在 enucleated 鸡蛋的体的房间的 Reprogramming 做了多丽,绵羊,在 1996 的第一个成功地克隆的哺乳动物。然而,绵羊的机制体的房间 reprogramming 还没被探讨了。而且,绵羊胚胎的茎(ES ) 细胞仍然不是可得到的,它限制精确修改基因的绵羊的产生。在这研究,我们报导体的房间能是的那只绵羊直接 reprogrammed 到导致的 pluripotent 用定义因素(Oct4, Sox2, c-Myc, Klf4, Nanog, Lin28, SV40 大 T 和 hTERT ) 的茎(iPS ) 房间。我们的观察显示从绵羊的体的细胞比从另外的种,在 iPS,细胞被报导了的体的细胞对改编更困难。我们证明绵羊 iPS 房间表示 ES 房间标记,包括碱的磷酸酶, Oct4, Nanog, Sox2, Rex1,阶段特定的胚胎的 antigen-1, TRA-1-60, TRA-1-81 和 E-cadherin。绵羊 iPS 房间展出了正常 karyotypes 并且能在 vitro 并且在 teratomas 区分进所有三细菌层。我们的学习可以帮助在绵羊揭示体的房间 reprogramming 的机制并且提供一个平台为绵羊 ES 房间探索文化条件。而且,绵羊 iPS 房间可以直接被用来产生精确修改基因的绵羊。Lei Bao Lixiazi He Jijun Chen Zhao Wu Jing Liao Lmgdun Rao Jiangtao Ren Hui Li Hui Zhu Lei Qian Yijun Gu Huimin Dai Xun Xu Jinqiu Zhou Wen Wang Chun Cui Lei Xiao 2011Cell Research2011,21,4:32
75-Hydroxymethylcytosine signatures in circulating cell-free DNA as diagnostic biomarkers for human cancers显示文摘象 5-methylcytosine (5mC ) 和 5-hydroxymethylcytosine (5hmC ) 那样的 DNA 修正是知道在哺乳动物影响全球基因表示的 epigenetic 标记。在人的染色体,与基因表示的靠近的关联和高化学的稳定性给他们的流行,这些 DNA epigenetic 标记能为癌症用作理想的 biomarkers 诊断。利用一种高度敏感、选择的化学标记技术,我们这里报导在传播没有房间的 DNA ( cfDNA )并且在从最近与 colorectal 诊断的 260 个病人的一个队收集的配对的肿瘤和邻近的纸巾的 genomic DNA ( gDNA )的 5hmC 的染色体宽的介绍,胃,胰腺,从 90 个健康个人的肝或甲状腺癌症和正常纸巾。5hmC 主要在与开的染色质和容许的 histone 修正重合的 transcriptionally 活跃的区域被散布。柔韧的联系癌症的 5hmC 签名在 cfDNA 被识别为特定的癌症类型是特征的。传播 cfDNA 的 5hmC 底 biomarkers colorectal 和胃的癌症是高度预兆的并且比常规 biomarkers 优异并且比得上从织物活体检视的 5hmC biomarkers。因此,这新策略能从血样品的分析为癌症的诊断和预后导致有效、最低限度地侵略的方法的发展。Wenshuai Li Xu Zhang Xingyu Lu Lei You Yanqun Song Zhongguang Luo Jun Zhang Ji Nie Wanwei Zheng Diannan Xu Yaping Wang Yuanqiang Dong Shulin Yu Jun Hong Jianping Shi Hankun Hao Fen Luo Luchun Hua Peng Wang Xiaoping Qian Fang Yuan Lianhuan Wei Ming Cui Taiping Zhang Quan Liao Menghua Dai Ziwen Liu Ge Chen Katherine Meckel Sarbani Adhikari Guifang Jia Marc B Bissonnette Xinxiang Zhang Yupei Zhao Wei Zhang Chuan He Jie Liu 2017Cell Research2017,27,10:30
8Modeling net primary productivity of the terrestrial ecosystem in China from 1961 to 2005显示文摘网络主要生产率(NPP ) 是代表生态系统的结构和函数的最重要的索引。NPP 能被动态全球植被模型(DGVM ) 模仿,它被设计相对环境变化代表植被动力学。这研究在气候,土壤,和地形学上与数据基于 DGVM 综合生物圈模拟器(朱鹭) 模仿了瓷器生态系统的 NPP。在瓷器陆上的生态系统的 NPP 模拟的朱鹭的适用性首先被验证。有另外的相关研究的比较显示范围和模拟的吝啬的价值通常在观察的限制以内;全面模式和全部的年度 NPP 接近与另外的模型一起进行的模拟。模拟基于遥感离 NPP 评价也靠近。确认证明那朱鹭能在瓷器自然生态系统在 NPP 的大规模模拟被利用。我们然后从 1961 ~ 2005 与气候变化数据模仿了 NPP,当温暖是特别地惹人注目的时。下列是模拟的结果。(1 ) 全部的 NPP 在过去的 45 年里从 3.61 GtC/yr 变化了到 4.24 GtC/yr 并且展出了最小的重要线性增加或减少。(2 ) 在增加的地区性的差别或在 NPP 的减少大,但是展出了一个不足道的全面线性趋势。NPP 在大多数部分衰退了东方并且华中,特别在黄土高原。(3 ) 类似于年度 NPP 的变化法律,季节的 NPP 也显示了不足道的增加或减少;趋势线在一般水平以内。(4 ) 在季节的 NPP 变化的地区性的差别大。NPP 在黄土高原在春天,夏天,和秋天衰退了,但是在西藏的高原的大多数部分增加了。YUAN Quanzhi WU Shaohong ZHAO Dongsheng DAI Erfu CHEN Li ZHANG Lei 2014Journal of Geographical Sciences2014,24,1:27
9Late Triassic sedimentary records in the northern Tethyan Himalaya:Tectonic link with Greater India显示文摘The Upper Triassic flysch sediments(Nieru Formation and Langjiexue Group)exposed in the Eastern Tethyan Himalayan Sequence are crucial for unraveling the controversial paleogeography and paleotectonics of the Himalayan orogen.This work reports new detrital zircon U-Pb ages and whole-rock geochemical data for clastic rocks from flysch strata in the Shannan area.The mineral modal composition data suggest that these units were mainly sourced from recycled orogen provenances.The chemical compositions of the sandstones in the strata are similar to the chemical composition of upper continental crust.These rocks have relatively low Chemical Index of Alteration values(with an average of 62)and Index of Compositional Variability values(0.69),indicating that they experienced weak weathering and were mainly derived from a mature source.The geochemical compositions of the Upper Triassic strata are similar to those of graywackes from continental island arcs and are indicative of an acidicintermediate igneous source.Furthermore,hornblende and feldspar experienced decomposition in the provenance,and the sediment became enriched in zircon and monazite during sediment transport.The detrital zircons in the strata feature two main age peaks at 225-275 Ma and 500-600 Ma,nearly continuous Paleoproterozoic to Neoproterozoic ages,and a broad inconspicuous cluster in the Tonian-Stenian(800-1200 Ma).The detrital zircons from the Upper Triassic sandstones in the study area lack peaks at 300-325 Ma(characteristic of the Lhasa block)and 1150-1200 Ma(characteristic of the Lhasa and West Australia blocks).Therefore,neither the Lhasa block nor the West Australia blocks likely acted as the main provenance of the Upper Triassic strata.Newly discovered Permian-Triassic basalt and mafic dikes in the Himalayas could have provided the 225-275 Ma detrital zircons.Therefore,Indian and Himalayan units were the main provenances of the flysch strata.The Tethyan Himalaya was part of the northern passive margin and was not an exotic terrane separated from India during the Permian to Early Cretaceous.This evidence suggests that the Neo-Tethyan ocean opened prior to the Late Triassic and that the Upper Triassic deposits were derived from continental crustal fragments adjacent to the northern passive continental margin of Greater India.Huawen Cao Yong Huang Guangming Li Linkui Zhang Jianyang Wu Lei Dong Zuowen Dai Liu Lu 2018Geoscience Frontiers2018,9,1:27
10High-entropy ceramics:Present status,challenges,and a look forward显示文摘High-entropy ceramics (HECs) are solid solutions of inorganic compounds with one or more Wyckoff sites shared by equal or near-equal atomic ratios of multi-principal elements.Although in the infant stage,the emerging of this new family of materials has brought new opportunities for material design and property tailoring.Distinct from metals,the diversity in crystal structure and electronic structure of ceramics provides huge space for properties tuning through band structure engineering and phonon engineering.Aside from strengthening,hardening,and low thermal conductivity that have already been found in high-entropy alloys,new properties like colossal dielectric constant,super ionic conductivity,severe anisotropic thermal expansion coefficient,strong electromagnetic wave absorption,etc.,have been discovered in HECs.As a response to the rapid development in this nascent field,this article gives a comprehensive review on the structure features,theoretical methods for stability and property prediction,processing routes,novel properties,and prospective applications of HECs.The challenges on processing,characterization,and property predictions are also emphasized.Finally,future directions for new material exploration,novel processing,fundamental understanding,in-depth characterization,and database assessments are given.Huimin XIANG Yan XING Fu-zhi DAI Hongjie WANG Lei SU Lei MIAO Guojun ZHANG Yiguang WANG Xiwei QI Lei YAO Hailong WANG Biao ZHAO Jianqiang LI Yanchun ZHOU 2021Journal of Advanced Ceramics2021,10,3:28
11Chinese Trauma Surgeon Association for management guidelines of vacuum sealing drainage application in abdominal surgeries-Update and systematic review显示文摘Vacuum sealing drainage (VSD) is frequently used in abdominal surgeries. However, relevant guidelines are rare. Chin ese Trauma Surge on Associati on orga nized a committee composed of 28 experts across China in July 2017, aiming to provide an evidence-based recommendation for the application of VSD in abdominal surgeries.Eleven questions regarding the use of VSD in abdominal surgeries were addressed:(1) which type of materials should be respectively chosen for the intraperitoneal cavity, retroperitoneal cavity and superficial incisions?(2) Can VSD be preventively used for a high-risk abdominal incision w让h primary suture?(3) Can VSD be used in severely contaminated/infected abdominal surgical sites?(4) Can VSD be used for temporary abdominal cavity closure under some special conditions such as severe abdominal trauma, infection, liver transplantation and intra-abdominal volume increment in abdominal compartment syndrome?(5) Can VSD be used in abdominal organ inflammation, injury, or postoperative drainage?(6) Can VSD be used in the treatment of intestinal fistula and pancreatic fistula?(7) Can VSD be used in the treatment of intra-abdominal and extra-peritoneal abscess?(8) Can VSD be used in the treatment of abdominal wall wounds, wound cavity, and defects?(9) Does VSD in crease the risk of bleeding?(10) Does VSD increase the risk of intestinal wail injury?(11) Does VSD increase the risk of peritoneal adhesion? Focusing on these questions, evidence-based recommendations were given accordingly. VSD was strongly recommended regarding the questions 2-4. Weak recommendations were made regarding questions 1 and 5-11. Proper use of VSD in abdominal surgeries can lower the risk of infection in abdominal incisions with primary suture, treat severely contaminated/infected surgical sites and facilitate temporary abdominal cavity closure.Yang Li Pei-Yuan Li Shi-Jing Sun Yuan-Zhang Yao Zhan-Fei Li Tao Liu Fan Yang Lian-Yang Zhang Xiang-Jun Bai Jing-Shan Huo Wu-Bing He Jun Ouyang Lei Peng Ping Hu Yan-An Zhu Ping Jin Qi-Feng Shao Yan-Feng Wang Rui-Wu Dai Pei-Yang Hu Hai-Ming Chen Ge-Fei Wang Yong-Gao Wang Hong-Xu Jin Chang-Ju Zhu Qi-Yong Zhang Biao Shao Xi-Guang Sang Chang-Lin Yin 2019Chinese Journal of Traumatology2019,22,1:26
12Submucosal tunneling and endoscopic resection of submucosal tumors at the esophagogastric junction显示文摘AIM: To evaluate the safety and efficacy of submucosal tunneling and endoscopic resection(STER) for treating submucosal tumors(SMTs).METHODS: Between August 2012 and October 2013, 21 patients with SMTs originating from the muscularis propria(MP) layer at the esophagogastric junction were treated by STER of their tumors. Key steps of the procedure include:(1) mucosal incision: a 2-cm longitudinal mucosal incision was made 5 cm proximal to the tumor;(2) submucosal tunneling: a submucosal tunnel was created 5 cm proximal to and 1 to 2 cm distal to the tumor;(3) tumor resection: the SMT was resected under direct endoscopic viewing;(4) hemostasis: while finishing the tumor resection, careful hemostasis of the MP defect and the tunnel was performed; and(5) mucosal closure: the mucosal incision site was closed by using hemostatic clips. During the operation, equipment used included a cap-fitted endoscope, an insulatedtip knife, a hook knife, hemostatic forceps, an injection needle, a snare, an endoclip, and a high-frequency generator. Carbon dioxide(CO2) insufflation was achieved by using a CO2 insufflator.RESULTS: The median age of the patients was 46.2 years(range, 35-59 years), and the majority were male(18 male vs 3 female). Complete resection rate was 100%(21/21). Eighteen lesions were resected en bloc. Mean tumor size was 23 mm(range, 10-40 mm), and mean procedure time was 62.9 min(range, 45-90 min). Pathological diagnosis of these tumors included leiomyoma(15 out of 21) and gastrointestinal stromal tumor(6 out of 21). Full-thickness MP resection was performed in 9 of 21 patients(42.9%), with mediastinal and subcutaneous emphysema occurring in all nine. At the completion of the procedure, all patients received closure of the incision with hemoclips. One patient required percutaneous drainage. The remaining 20patients required no further endoscopic or surgical intervention. There were no incidents of massive or delayed bleeding. The median follow-up period after the procedure was 6 mo(range, 2-14 mo). During followup, no patients were found to have residual or recurrent tumor or esophageal stricture.CONCLUSION: STER is safe, effective and feasible, which provides accurate histopathologic evaluation and curative treatment for SMTs originating from the MP layer at the esophagogastric junction.De-Jun Zhou Zhen-Bo Dai Malcolm M Wells Dan-Lei Yu Jing Zhang Lei Zhang 2015World Journal of Gastroenterology2015,21,2:20
13Effects of slow or controlled release fertilizer types and fertilization modes on yield and quality of rice显示文摘There is limited information about the influence of slow or controlled release fertilizer(S/CRF) on rice yield and quality. In this study, japonica rice cultivar Nanjing 9108 was used to study the effects of three different S/CRFs(polymer-coated urea(PCU), sulfur-coated urea(SCU), and urea formaldehyde(UF)) and two fertilization modes(both S/CRF and common urea(CU) as basal fertilizer, S/CRF as basal and CU as tillering fertilizer) on rice yield and quality. CU only was applied separately as control(CK). Results showed that, rice grain yield, chalky kernel rate, chalky area, overall chalkiness, and the content of gliadin, glutenin, and protein, all showed the trends of UF>PCU>SCU within the same fertilization mode, and showed the trends of S/CRF as basal and CU as tillering fertilizer>both S/CRF and CU as basal fertilizer within the same type of S/CRF. In contrast, the contents of amylose, amylopectin, and starch, as well as taste value, and peak and hot viscosity showed trends of SCU>PCU>UF, and the trends of both S/CRF and CU as basal fertilizer>S/CRF as basal and CU as tillering fertilizer. Among S/CRF treatments and fertilization modes, taste values of cooked rice were positively correlated with amylose, amylopectin, and starch contents, as well as gel consistency, peak viscosity, hot viscosity, and cool viscosity, while negatively correlated with globulin, gliadin, glutenin, and protein contents. The types of S/CRF and fertilization modes are important for improving rice yield and quality. Compared to CK, higher yield and similar quality of rice was achieved with UF as basal and CU as tillering fertilizer, and similar yield with improved appearance and eating and cooking quality of rice was achieved with either both UF and CU as basal fertilizer, or PCU as basal and CU as tillering fertilizer.WEI Hai-yan CHEN Zhi-feng XING Zhi-peng ZHOU Lei LIU Qiu-yuan ZHANG Zhen-zhen JIANG Yan HU Ya-jie ZHU Jin-yan CUI Pei-yuan DAI Qi-gen ZHANG Hong-cheng 2018Journal of Integrative Agriculture2018,17,10:19
14Postponed and reduced basal nitrogen application improves nitrogen use efficiency and plant growth of winter wheat显示文摘Excessive nitrogen(N) fertilization with a high basal N ratio in wheat can result in lower N use efficiency(NUE) and has led to environmental problems in the Yangtze River Basin, China. However, wheat requires less N fertilizer at seedling growth stage, and its basal N fertilizer utilization efficiency is relatively low; therefore, reducing the N application rate at the seedling stage and postponing the N fertilization period may be effective for reducing N application and increasing wheat yield and NUE. A 4-year field experiment was conducted with two cultivars under four N rates(240 kg N ha–1(N240), 180 kg N ha–1(N180), 150 kg N ha–1(N150), and 0 kg N ha–1(N0)) and three basal N application stages(seeding(L0), fourleaf stage(L4), and six-leaf stage(L6)) to investigate the effects of reducing the basal N application rate and postponing the basal N fertilization period on grain yield, NUE, and N balance in a soil-wheat system. There was no significant difference in grain yield between the N180 L4 and N240 L0(control) treatments, and the maximum N recovery efficiency and N agronomy efficiency were observed in the N180 L4 treatment. Grain yield and NUE were the highest in the L4 treatment. The leaf area index, flag leaf photosynthesis rate, flag leaf nitrate reductase and glutamine synthase activities, dry matter accumulation, and N uptake post-jointing under N180 L4 did not differ significantly from those under N240 L0. Reduced N application decreased the inorganic N content in the 0–60-cm soil layer, and the inorganic N content of the L6 treatment was higher than those of the L0 and L4 treatments at the same N level. Surplus N was low under the reduced N rates and delayed basal N application treatments. Therefore, postponing and reducing basal N fertilization could maintain a high yield and improve NUE by improving the photosynthetic production capacity, promoting N uptake and assimilation, and reducing surplus N in soil-wheat systems.TIAN Zhong-wei LIU Xiao-xue GU Shi-lu YU Jin-hong ZHANG Lei ZHANG Wei-wei JIANG Dong CAO Wei-xing DAI Ting-bo 2018Journal of Integrative Agriculture2018,17,12:18
15High porosity and low thermal conductivity high entropy(Zr0.2Hf0.2Ti0.2Nb0.2Ta0.2C显示文摘Porous ultra-high temperature ceramics(UHTCs)are promising for ultrahigh-temperature thermal insulation applications.However,the main limitations for their applications are the high thermal conductivity and densification of porous structure at high temperatures.In order to overcome these obstacles,herein,porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C was prepared by a simple method combing in-situ reaction and partial sintering.Porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))C possesses homogeneous microstructure with grain size in the range of 100–500 nm and pore size in the range of 0.2–1μm,which exhibits high porosity of 80.99%,high compressive strength of 3.45 MPa,low room temperature thermal conductivity of 0.39 W·m^-1K^-1,low thermal diffusivity of 0.74 mm^2·s^-1and good high temperature stability.The combination of these properties renders porous high entropy(Zr(0.2)Hf(0.2)Ti(0.2)Nb(0.2)Ta(0.2))Cpromising as light-weight ultrahigh temperature thermal insulation materials.Heng Chen Huimin Xiang Fu-Zhi Dai Jiachen Liu Yiming Lei Jie Zhang Yanchun Zhou 2019Journal of Materials Science & Technology2019,35,8:16
16Combined transjugular intrahepatic portosystemic shunt and other interventions for hepatocellular carcinoma with portal hypertension显示文摘AIM: To evaluate combination transjugular intrahepatic portosystemic shunt(TIPS) and other interventions for hepatocellular carcinoma(HCC) and portal hypertension.METHODS: Two hundred and sixty-one patients with HCC and portal hypertension underwent TIPS combined with other interventional treatments(transarterial chemoembolization/transarterial embolization,radiofrequency ablation,hepatic arterio-portal fistulas embolization,and splenic artery embolization) from January 1997 to January 2010 at Beijing Shijitan Hospital. Two hundred and nine patients(121 male and 88 female,aged 25-69 years,mean 48.3 ± 12.5 years) with complete clinical data were recruited. We evaluated the safety of the procedure(procedurerelated death and serious complications),change of portal vein pressure before and after TIPS,symptom relief [e.g.,ascites,hydrothorax,esophageal gastricfundus variceal bleeding(EGVB)],cumulative rates of survival,and distributary channel restenosis. The characteristics of the patients surviving ≥ 5 and < 5 years were also analyzed.RESULTS: The portosystemic pressure was decreased from 29.0 ± 4.1 mm Hg before TIPS to 18.1 ± 2.9 mm Hg after TIPS(t = 69.32,P < 0.05). Portosystemic pressure was decreased and portal hypertension symptoms were ameliorated. During the 5 year followup,the total recurrence rate of resistant ascites or hydrothorax was 7.2%(15/209); 36.8%(77/209) for EGVB; and 39.2%(82/209) for hepatic encephalopathy. The cumulative rates of distributary channel restenosis at 1,2,3,4,and 5 years were 17.2%(36/209),29.7%(62/209),36.8%(77/209),45.5%(95/209) and 58.4%(122/209),respectively. No procedure-related deaths and serious complications(e.g.,abdominal bleeding,hepatic failure,and distant metastasis) occurred. Moreover,Child-Pugh score,portal vein tumor thrombosis,lesion diameter,hepatic arterio-portal fistulas,HCC diagnosed before or after TIPS,stent type,hepatic encephalopathy,and type of other interventional treatments were related to 5 year survival after comparing patient characteristics.CONCLUSION: TIPS combined with other interventional treatments seems to be safe and efficacious in patients with HCC and portal hypertension.Bin Qiu Meng-Fei Zhao Zhen-Dong Yue Hong-Wei Zhao Lei Wang Zhen-Hua Fan Fu-Liang He Shan Dai Jian-Nan Yao Fu-Quan Liu 2015World Journal of Gastroenterology2015,21,43:16
17Geographical characteristics of China’s wetlands derived from remotely sensed data显示文摘In this paper, we report the first wetland mapping of the entire China using Landsat enhanced thematic mapper plus (ETM+) data. These data were obtained from the Global Land Cover Facility at the University of Maryland spanning from 1999 to 2002. A total of 597 scenes of Landsat images were georeferenced and mosaiced. Manual image interpretation of satellite images was aided with elevation data, soil data, land cover/land use data and Google Earth. The minimum mapping unit is 10 pixel × 10 pixel, equivalent to 9 ha. The aim of our first round of mapping was only targeted at the boundary delineation of any type of wetland except those wetlands that are under agricultural use (i.e., paddy fields), which has already been well mapped by others. Our interpretation results indicate that a total of 359478 km2 of wetlands are of non-agricultural use. Among our preliminarily mapped wetland, 339353 km2 are inland wetland, 2786 km2 are non-agricultural artificial wetland, and 17609 km2 are coastal wetland. Because low-tide is rarely captured in satellite images, an under-estimation of coastal wetland is inevitable. We conducted some statistics based on our mapped wetlands and compared them with those previously obtained from a number of sources including a land cover/land use map made with satellite images during the late 1990s and early 2000s, a marshland map developed in approximately the same period, survey data of coastal wetland in early 1980s, and area data for approximately 400 larger patches of marshland in China compiled in 1996. Because some inconsistencies exist in the guidelines of those different wetland surveys, difference in area is expected. Some further comparison indicates that the wetland distributions derived from the preliminary wetland map are reasonable and more objective than other sources. The mapping process also indicated that the method adopted by us was efficient and cost-effective. We also found that in order to ensure comparability of the wetland maps developed at different times, a set of standard guidelines on the wetland categories to be mapped, and the mapping methods to be used must be well conceived, developed and effectively employed. We carried out some initial geographical analysis on the distribution of wetlands.NIU ZhenGuo GONG Peng CHENG Xiao GUO JianHong WANG Lin HUANG HuaBing SHEN ShaoQing WU YunZhao WANG XiaoFeng WANG XianWei YING Qing LIANG Lu ZHANG LiNa WANG Lei YAO Qian YANG ZhenZhong GUO ZiQi DAI YongJiu 2009Science China Earth Sciences2009,52,6:15
18Upregulation of CD81 in trophoblasts induces an imbalance of Treg/Th17 cells by promoting IL-6 expression in preeclampsia显示文摘The disturbance of maternal immune tolerance to a semiallogeneic fetus is recognized as one of the key pathologies of preeclampsia(PE),in which an imbalance between the inflammation-limiting regulatory T cells(Tregs)and the inflammationmediating Th17 cells plays an essential role.Previously,we reported that the abnormal upregulation of tetraspannin CD81 in trophoblast cells(fetal component)participated in the pathogenesis of PE.However,as one of the potential immune regulatory molecules,whether CD81 induces PE by interfering with the balance of the maternal immune system has not yet been clarified.Thus,we investigated the relationship between the upregulation of CD81 in trophoblast cells and the imbalance of Treg and Th17 cells in mothers.Here,we demonstrated that upregulation of CD81 in trophoblast cells was accompanied by a decrease in Treg cells and an increase in Th17 cells in both the basal plate(placental maternal side)and peripheral blood of patients with PE.In vitro culture of naïve T cells with medium from the CD81-overexpressing trophoblast cell line HTR-8 resulted in enhanced differentiation of T cells into Th17 cells and decreased the formation of Tregs,which was dependent on the paracrine signaling of IL-6 in trophocytes,induced by CD81.In a CD81-induced PE rat model,we found a significant shift of T cell differentiation towards Th17 cells,and administration of IL-6 antibody mitigated the PE phenotype and the imbalance of the Treg/Th17 cells.These results define a vital regulatory cascade involving trophocyte-derived CD81,IL-6,and maternal Treg/Th17 cells in the pathogenesis of PE and suggests new therapeutic approaches based on CD81 and IL-6 downregulation to prevent human PE.Hailin Ding Yimin Dai Yi Lei Zhiyin Wang Dan Liu Ruotian Li Li Shen Ning Gu Mingming Zheng Xiangyu Zhu Guangfeng Zhao Yali Hu 2019Cellular & Molecular Immunology2019,16,3:15
19IL-10 Gene Modified Dendritic Cells Inhibit T Helper Type 1-Mediated Alloimmune Responses and Promote Immunological Tolerance in Diabetes显示文摘Dendritic cells (DCs) have the potency to regulate the outcome of autoimmunity through the modulation of immune responses. The induction of antigen specific tolerance is critical for prevention and treatment of allograft rejection. In the present study,we transfected IL-10 gene into DCs and investigated their effect on inhibition of lymphocyte activity in vitro and induction of immune tolerance on islet allograft in mice. An IDDM C57BL/6 mouse model was induced by streptozotocin. The islet cells isolated from the BALB/c mice were transplanted into the kidney capules of the model mice followed by injection of IL-10 modified DCs (mDCs). The results showed that mDCs could significantly inhibit T lymphocyte proliferation mediated by allotype cells and induce its apoptosis,whereas,unmodified DCs (umDCs) could promote the murine lymphocyte proliferation markedly. The injection of mDCs could prolong the survival of allotype islet transplanted IDDM mice. The average plasma glucose (PG) level in mDCs treated mice returned to normal within 3 days and lasted for about 2 weeks. The rejection response in control mice occurred for 5 days after transplantation. The level of IFN-γ was lower while IL-4 was higher in mDCs treated mice than that in umDCs treated mice,which indicated that Th1/Th2 deviation occurred. Our studies suggest that IL-10 gene modified DCs can induce the immune tolerance to islet graft and prolong survival of the recipients by the inhibiting of T cell proliferation in allotype mice.Huifen Zhu Wenhong Qiu Ping Lei Wei Zhou Xue Wen Fengrong He Li Li Hong Dai Guanxin Shen Feili Gong 2008Cellular & Molecular Immunology2008,5,1:14
20Coal facies evolution of the main minable coal-bed in the Heidaigou Mine, Jungar Coalfield, Inner Mongolia, northern China显示文摘The No. 6 Coal-bed from the Heidaigou Mine, Jungar Coalfield, Inner Mongolia is a super-large Ga deposit. The dominant carrier of Ga is boehmite in coal. The study of coal facies may provide genetic enrichment information of Ga and its carrier (boehmite) in the Ga deposit. On the basis of study on coal petrology and mineralogy, it was found that the No. 6 Coal-bed from the Heidaigou Mine of Jungar was enriched in inertinites and the microlitho-types were dominated by clarodurite. The maceral morphological features and association indicate that the coal-bed was formed in a dry sedimentary environment or in a periodic dry sedimentary environment caused by the alternating variations of groundwater level. The optimum conditions for the enrichment of Ga and its particular carrier (boehmite) were dominated by four transitional conditions: (1) the upper delta plain which was the transitional zone between alluvial and lower delta plains, (2) the transitional zone between the dry and wet forest swamps, being slightly apt to the dry one, (3) the transitional tree density between the thick and loose ones, and (4) the low moor that was the transitional zone between two high moors during peat accumulation.DAI ShiFeng REN DeYi LI ShengSheng ZHAO Lei ZHANG Yong 2007Science China Earth Sciences2007,50,z2:14
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