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1912篇 您的检索式:作者名="Fischer H"
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1On the combined effect of soil fertility and topography on tree growth in subtropical forest ecosystems—a study from SE China显示文摘Aims The aim of our research was to understand small-scale effects of topography and soil fertility on tree growth in a forest biodiversity and ecosystem functioning(BEF)experiment in subtropical SE China.Methods Geomorphometric terrain analyses were carried out at a spatial resolution of 5×5 m.Soil samples of different depth increments and data on tree height were collected from a total of 566 plots(667 m2 each).The soils were analyzed for carbon(soil organic carbon[SOC]),nitrogen,acidity,cation exchange capacity(CEC),exchangeable cations and base saturation as soil fertility attributes.All plots were classified into geomorphological units.Analyses of variance and linear regressions were applied to all terrain,soil fertility and tree growth attributes.Important Findings In general,young and shallow soils and relatively small differences in stable soil properties suggest that soil erosion has truncated the soils to a large extent over the whole area of the experiment.This explains the concurrently increasing CEC and SOC stocks downslope,in hollows and in valleys.However,colluvial,carbon-rich sediments are missing widely due to the convexity of the footslopes caused by uplift and removal of eroded sediments by adjacent waterways.The results showed that soil fertility is mainly influenced by topography.Monte-Carlo flow accumulation(MCCA),curvature,slope and aspect significantly affected soil fertility.Furthermore,soil fertility was affected by the different geomorphological positions on the experimental sites with ridge and spur positions showing lower exchangeable base cation contents,especially potassium(K),due to leaching.This geomorphological effect of soil fertility is most pronounced in the topsoil and decreases when considering the subsoil down to 50 cm depth.Few soil fertility attributes affect tree height after 1-2 years of growth,among which C stocks proved to be most important while pH_(KCl)and CEC only played minor roles.Nevertheless,soil acidity and a high proportion of Al on the exchange complex affected tree height even after only 1-2 years growth.Hence,our study showed that forest nutrition is coupled to a recycling of litter nutrients,and does not only depend on subsequent supply of nutrients from the mineral soil.Besides soil fertility,topography affected tree height.We found that especially MCCA as indicator of water availability affected tree growth at small-scale,as well as aspect.Overall,our synthesis on the interrelation between fertility,topography and tree growth in a subtropical forest ecosystem in SE China showed that topographic heterogeneity lead to ecological gradients across geomorphological positions.In this respect,small-scale soil-plant interactions in a young forest can serve as a driver for the future development of vegetation and biodiversity control on soil fertility.In addition,it shows that terrain attributes should be accounted for in ecological research.Thomas Scholten Philipp Goebes Peter Kühn Steffen Seitz Thorsten Assmann Jürgen Bauhus Helge Bruelheide Francois Buscot Alexandra Erfmeier Markus Fischer Werner Härdtle Jin-Sheng He Keping Ma Pascal A.Niklaus Michael Scherer-Lorenzen Bernhard Schmid Xuezheng Shi Zhengshan Song Goddert von Oheimb Christian Wirth Tesfaye Wubet Karsten Schmidt 2017Journal of Plant Ecology2017,10,1:22
2Factors associated with long-term survival after liver transplantation:A retrospective cohort study显示文摘AIM To identify predictive factors associated with long-term patient and graft survival(> 15 years) in liver transplant recipients.METHODS Medical charts of all de novo adult liver transplant recipients(n = 140) who were transplanted in Hamburg between 1997 and 1999 were retrospectively reviewed.In total,155 transplantations were identified in this time period(15 re-transplantations).Twenty-six orthotopic liver transplant(OLT) recipients were early lost to followup due to moving to other places within 1 year after transplantation.All remaining 114 patients were included in the analysis.The following recipient factors were analysed:Age,sex,underlying liver disease,pre-OLT body mass index(BMI),and levels of alanine aminotransferase(ALT),bilirubin,creatinine and gammaglutamyltransferase(gamma-GT),as well as warm and cold ischemia times.Furthermore,the following donor factors were assessed:Age,BMI,cold ischemia time and warm ischemia time.All surviving patients were followed until December 2014.We divided patients into groups according to their underlying diagnosis:(1) hepatocellularcarcinoma(n = 5,4%);(2) alcohol toxic liver disease(n = 25,22.0%);(3) primary sclerosing cholangitis(n = 6,5%);(4) autoimmune liver diseases(n = 7,6%);(5) hepatitis C virus cirrhosis(n = 15,13%);(6) hepatitis B virus cirrhosis(n = 21,19%);and(7) other(n = 35,31%).The group 'other' included rare diagnoses,such as acute liver failure,unknown liver failure,stenosis and thrombosis of the arteria hepatica,polycystic liver disease,Morbus Osler and Caroli disease.RESULTS The majority of patients were male(n = 70,61%).Age and BMI at the time point of transplantation ranged from 16 years to 69 years(median:53 years) and from 15 kg/m^2 to 33 kg/m^2(median:24),respectively.Sixty-six OLT recipients(58%) experienced a follow-up of 15 years after transplantation.Recipient's age(P = 0.009) and BMI(P = 0.029) were identified as risk factors for death by χ~2-test.Kaplan-Meier analysis confirmed BMI or age above the median as predictors of decreased long-term survival(P = 0.008 and P = 0.020).Hepatitis B as underlying disease showed a trend for improved long-term survival(P = 0.049,χ~2-test,P = 0.055;Kaplan-Meier analysis,Log rank).Pre-transplant bilirubin,creatinine,ALT and gamma-GT levels were not associated with survival in these patients of the pre-era of the model of end stage liver disease.CONCLUSION The recipients' age and BMI were predictors of longterm survival after OLT,as well as hepatitis B as underlying disease.In contrast,donors' age and BMI were not associated with decreased survival.These findings indicate that recipient factors especially have a high impact on long-term outcome after liver transplantation.Sven Pischke Marie C Lege Moritz von Wulffen Antonio Galante Benjamin Otto Malte H Wehmeyer Uta Herden Lutz Fischer Bjorn Nashan Ansgar W Lohse Martina Sterneck 2017World Journal of Hepatology2017,9,8:5
3Ultrapure dialysis fluid slows loss of residual renal function in new dialysis patients.显示文摘Schiffl H Lang SM Fischer R 0,,:3
4National Forest Inventories capture the multifunctionality of managed forests in Germany显示文摘Background:Forests perform various important ecosystem functions that contribute to ecosystem services.In many parts of the world,forest management has shifted from a focus on timber production to multi-purpose forestry,combining timber production with the supply of other forest ecosystem services.However,it is unclear which forest types provide which ecosystem services and to what extent forests primarily managed for timber already supply multiple ecosystem services.Based on a comprehensive dataset collected across 150 forest plots in three regions differing in management intensity and species composition,we develop models to predict the potential supply of 13 ecosystem services.We use those models to assess the level of multifunctionality of managed forests at the national level using national forest inventory data.Results:Looking at the potential supply of ecosystem services,we found trade-offs(e.g.between both bark beetle control or dung decomposition and both productivity or soil carbon stocks)as well as synergies(e.g.for temperature regulation,carbon storage and culturally interesting plants)across the 53 most dominant forest types in Germany.No single forest type provided all ecosystem services equally.Some ecosystem services showed comparable levels across forest types(e.g.decomposition or richness of saprotrophs),while others varied strongly,depending on forest structural attributes(e.g.phosphorous availability or cover of edible plants)or tree species composition(e.g.potential nitrification activity).Variability in potential supply of ecosystem services was only to a lesser extent driven by environmental conditions.However,the geographic variation in ecosystem function supply across Germany was closely linked with the distribution of main tree species.Conclusions:Our results show that forest multifunctionality is limited to subsets of ecosystem services.The importance of tree species composition highlights that a lack of multifunctionality at the stand level can be compensated by managing forests at the landscape level,when stands of complementary forest types are combined.These results imply that multi-purpose forestry should be based on a variety of forest types requiring coordinated planning across larger spatial scales.Nadja K.Simons María R.Felipe-Lucia Peter Schall Christian Ammer Jürgen Bauhus Nico Blüthgen Steffen Boch François Buscot Markus Fischer Kezia Goldmann Martin M.Gossner Falk Hänsel Kirsten Jung Peter Manning Thomas Nauss Yvonne Oelmann Rodica Pena Andrea Polle Swen C.Renner Michael Schloter Ingo Schöning Ernst-Detlef Schulze Emily F.Solly Elisabeth Sorkau Barbara Stempfhuber Tesfaye Wubet Jörg Müller Sebastian Seibold Wolfgang W.Weisser 2021Forest Ecosystems2021,8,1:2
5Genotype-dependent activation or repression of HBV enhancer Ⅱ by transcription factor COUP-TF1显示文摘AIM: To study the expression of HBV enhancer Ⅱ by transcription factor COUP-TF1. METHODS: In order to study the regulation of HBV variants in the vicinity of the NRRE we cloned luciferase constructs containing the HBV enhancer Ⅱ from variants and from HBV genotypes A and D and cotransfected them together with expression vectors for COUP-TF1 into HepG2 cells. RESULTS: Our fi ndings show that enhancer Ⅱ of HBV genotype A is also repressed by COUP-TF1. In contrast, two different enhancer Ⅱ constructs of HBV genotype D were activated by COUP-TF1. The activation was independent of the NRRE because a natural variant with a deletion of nt 1763-1770 was still activated by COUP- TF1. CONCLUSION: Regulation of transcription of the HBV genome seems to differ among HBV genomes derived from different genotypes. These differences in transcriptional control among HBV genotypes may be the molecular basis for differences in the clinical course among HBV genotypes.Silke F Fischer Katja Schmidt Nicola Fiedler Dieter Glebe Christian Schüttler Jianguang Sun Wolfram H Gerlich Reinald Repp Stephan Schaefer 2006World Journal of Gastroenterology2006,12,37:2
6Perioperative outcomes of major hepatic resections under low central venous pressure anesthesia: blood loss, blood transfusion, and the risk of postoperative renal dysfunction显示文摘Jose A Melendez Vittoria Arslan Mary E Fischer David Wuest William R Jarnagin Yuman Fong Leslie H Blumgart 1998Journal of the American College of Surgeons1998,,6:2
7Stem cell division is regulated by the microRNA pathway显示文摘HATFIELD S D SHCHERBATA H R FISCHER K A 2005Nature2005,435,7044:1
8Relationship between endotracheal tube leakage and under - reading of tidal volume in neonatal ventilators 显示文摘Mahmoud RA Fischer HS Proquitte H 2009Acta Paediatr2009,98,7:1
9Reducing the peak-to-average power ratio of multicarrier modulation by selected mapping 显示文摘R W Bauml R F H Fischer J B Huber 1996Electronics Letters1996,32,22:1
10显示文摘Fischer R Schrefl T Kronmüller H 1996J Magn Magn Mater1996,153,:1
11RF MEMS for ubiquitous wireless connectivity:Part 1-Fabrication显示文摘De Los Santos H J Fischer G Tilmans H A C 2004IEEE Microwave Mag2004,5,4:1
12Rapid metagenomic diagnostics for suspected outbreak of severe pneumonia 显示文摘Fischer N Rohde H Indenbirken D 2014Emerg Infect Dis2014,20,6:1
13Development of apan-Simbu real time RT-PCR for the detection of Simbu serogroup viruses and comparison with SBV diagnostic PCR systems显示文摘Fischer M Schirrmeier H Wernike K 2013Virol J2013,10,:1
14Prospective muhicentre study on the prediction of relapse after antithyroid drug treatment in patients with Graves' disease显示文摘Schleusener H Schwander J Fischer C 1989Acta Endocrinol (Copenh)1989,120,6:1
15Microstructure of Fe-Cr-C hardfacing alloy with additions of Nb, Ti, B 显示文摘Betas H Fischer A 1997Materials Characterization1997,39,24:1
16In vivo fracture resistance of implant-supported all-ceramic restorations显示文摘Yildirim M Fischer H Marx R Edelhoff D 2003J Prosthet Dent2003,90,4:1
17Molecular basis for the herbicide resistance of roundup ready crops显示文摘Todd F Han H J Healy-Fried M L Fischer M Schnbrunn E 2006Proceedings of the National Academy of Sciences of the United States of America2006,,13:1
18pH values and redox potentials in microsites of the rhizosphere显示文摘Fischer W R Flessa H Schaller G 1989Z Pflanzenernahr Bodenk1989,152,2:1
19C of the head by use of reduced current and kilovoltage:relationship between image quality and dose reduction显示文摘Cohnen M Fischer H Hamacher J 2000AJNR2000,21,:1
20Gas analysis by infra- red spectroscopy as a tool for electrical fault diagnostics in SF~ insulated equipment显示文摘Heise H M Kurte R Fischer P 1997Fresenius Journal of Analytical Chem istry1997,358,5:1
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