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71.
Antibody activation of mutant human fructosediphosphate aldolase B in liver extracts of patients with hereditary fructose intolerance 总被引:1,自引:0,他引:1
R Gitzelmann B Steinmann C Bally H G Lebherz 《Biochemical and biophysical research communications》1974,59(4):1270-1277
Antiserum to crystallized fructosediphosphate aldolase B from human liver precipitated/inhibited the antigen in solution. It activated the mutant enzyme in liver extracts of 3 patients with hereditary fructose intolerance but not in 2 others. It was concluded that genetic variability existed between these patients. In vitro activation of a defective human enzyme, demonstrated here for the first time, indicates that in vivo restoration of activity of mutant enzymes may become feasible. 相似文献
72.
Dr. habil. Eike Libbert 《Planta》1955,45(5):405-425
Ohne Zusammenfassung 相似文献
73.
Priv.-Doz. Dr. Brita von Gaudecker Gerhard G. Steinmann Martin Leo Hansmann Joachim Harpprecht Novica M. Milicevic Hans Konrad Müller-Hermelink 《Cell and tissue research》1986,244(2):403-412
Summary The epithelial framework of the human thymus has been studied in parallel by immunohistochemical methods at the light- and electron-microscopic levels. Different monoclonal antibodies were used, reacting with components of the major histocompatibility complex, keratins, thymic hormones and other as yet antigenically undefined substances, which show specific immunoreactivities with human thymus epithelial cells.The electron-microscopic immunocytochemical observations clearly confirm microtopographical differences of epithelial cells not only between the thymic cortex and medulla, but also within the cortex itself. At least four subtypes of epithelial cells could be distinguished: 1) the cortical surface epithelium; 2) the main cortical epithelial cells and thymic nurse cells; 3) the medullary epithelial cells; and 4) the epithelial cells of Hassall's corpuscles.The various epithelial cell types of the thymus display several common features like tonofilaments, desmosomes and some surface antigens as demonstrated by anti-KiM3. In other respects, however, they differ from each other. The cortical subtype of thymic epithelial cells including the thymic nurse cells shows a distinct pattern of surface antigens reacting positively with antibodies against HLA-DR (anti-HLA-DR) and anti-21A62E. Electron-microscopic immunocytochemistry with these antibodies clearly reveals a surface labeling and a narrow contact to cortical thymocytes particularly in the peripheral cortical regions. An alternative staining pattern is realized by antibodies to some antigens associated with other subtypes of thymic epithelial cells. Medullary epithelial cells as well as the cortical surface epithelium react likewise positively with antibodies to special surface antigens (anti-Ep-1), to special epitopes of cytokeratin (anti-IV/82), and to thymic hormones (anti-FTS). The functional significance of distinct microenvironments within the thymus provided by different epithelial cells is discussed in view of the maturation of T-precursor cells.Glossary of Abbreviations
Anti-X
anti-X antibody
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APUD-cells
amine precursor uptake and decarboxylation (gastro-intestinal endocrine cells)
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DAB
diamino-benzidine
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DMSO
dimethyl sulfoxide
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FTS
facteur thymique sérique
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HLA-A, B, C
human leucocyte antigen, A, B, C-region related
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HLA-DR
human leucocyte antigen, D-region related
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IDC
interdigitating cell
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MHC
major histocompatibility gene complex
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PBS
phosphate-buffered saline
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TNC
thymic nurse cell
This investigation was supported by grants from the Deutsche Forschungsgemeinschaft, and its Sonderforschungsbereich 111Fellow of the Alexander von Humbold-Stiftung, Institute of Pathology, University of Würzburg, Federal Republic of GermanyThe authors appreciate the contribution of human thymus tissue from Professor Alexander Bernhard, Abteilung kardiovasculäre Chirurgie der Universität Kiel; the gift of monoclonal antibodies from Dr. M.J.D. Anderson, Dr. M. Dardenne and Dr. H.J. Radzun; and the excellent technical assistence of Mrs. O.M. Bracker, Mrs. H. Hansen, Mrs. R. Köpke, Mrs. M. v. Kolszynski, Mrs. J. Quitzau, Mrs. H. Siebke, and Mrs. H. Waluk 相似文献
74.
Ohne Zusammenfassung 相似文献
75.
V. Haecker und Steinmann 《Molecular & general genetics : MGG》1908,1(1):461-468
Ohne Zusammenfassung 相似文献
76.
Liang Guo Ji Chen Eike Luedeling Jin-Sheng He Jimin Cheng Zhongming Wen Changhui Peng 《Plant and Soil》2018,425(1-2):177-188
Aims
The response of vegetation productivity to global warming is becoming a worldwide concern. While most reports on responses to warming trends are based on measured increases in air temperature, few studies have evaluated long-term variation in soil temperature and its impacts on vegetation productivity. Such impacts are especially important for high-latitude or high-altitude regions, where low temperature is recognized as the most critical limitation for plant growth.Methods
We used Partial Least Squares regression to correlate long-term aboveground net primary productivity (ANPP) data of an alpine grassland on the Qinghai-Tibetan Plateau with daily air and soil temperatures during 1997–2011. We also analyzed temporal trends for air temperature and soil temperature at different depths.Results
Soil temperatures have steadily increased at a rate of 0.4–0.9 °C per decade, whereas air temperatures showed no significant trend between 1997 and 2011. While temperature increases during the growing season (May–August) promoted aboveground productivity, warming before the growing season (March–April) had a negative effect on productivity. The negative effect was amplified in the soil layers, especially at 15 cm depth, where variation in aboveground productivity was dominated by early-spring soil warming, rather than by increasing temperature during the growing season.Conclusions
Future warming, especially in winter and spring, may further reduce soil water availability in early spring, which may slow down or even reverse the increases in grassland aboveground productivity that have widely been reported on the Qinghai-Tibetan Plateau.77.
78.
79.
Contrasting changes in the abundance and diversity of North American bird assemblages from 1971 to 2010 下载免费PDF全文
Aafke M. Schipper Jonathan Belmaker Murilo Dantas de Miranda Laetitia M. Navarro Katrin Böhning‐Gaese Mark J. Costello Maria Dornelas Ruud Foppen Joaquín Hortal Mark A. J. Huijbregts Berta Martín‐López Nathalie Pettorelli Cibele Queiroz Axel G. Rossberg Luca Santini Katja Schiffers Zoran J. N. Steinmann Piero Visconti Carlo Rondinini Henrique M. Pereira 《Global Change Biology》2016,22(12):3948-3959
Although it is generally recognized that global biodiversity is declining, few studies have examined long‐term changes in multiple biodiversity dimensions simultaneously. In this study, we quantified and compared temporal changes in the abundance, taxonomic diversity, functional diversity, and phylogenetic diversity of bird assemblages, using roadside monitoring data of the North American Breeding Bird Survey from 1971 to 2010. We calculated 12 abundance and diversity metrics based on 5‐year average abundances of 519 species for each of 768 monitoring routes. We did this for all bird species together as well as for four subgroups based on breeding habitat affinity (grassland, woodland, wetland, and shrubland breeders). The majority of the biodiversity metrics increased or remained constant over the study period, whereas the overall abundance of birds showed a pronounced decrease, primarily driven by declines of the most abundant species. These results highlight how stable or even increasing metrics of taxonomic, functional, or phylogenetic diversity may occur in parallel with substantial losses of individuals. We further found that patterns of change differed among the species subgroups, with both abundance and diversity increasing for woodland birds and decreasing for grassland breeders. The contrasting changes between abundance and diversity and among the breeding habitat groups underscore the relevance of a multifaceted approach to measuring biodiversity change. Our findings further stress the importance of monitoring the overall abundance of individuals in addition to metrics of taxonomic, functional, or phylogenetic diversity, thus confirming the importance of population abundance as an essential biodiversity variable. 相似文献