首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2408篇
  免费   172篇
  国内免费   1篇
  2021年   27篇
  2019年   29篇
  2018年   24篇
  2016年   48篇
  2015年   58篇
  2014年   84篇
  2013年   96篇
  2012年   114篇
  2011年   118篇
  2010年   74篇
  2009年   83篇
  2008年   98篇
  2007年   96篇
  2006年   91篇
  2005年   92篇
  2004年   85篇
  2003年   92篇
  2002年   102篇
  2001年   57篇
  2000年   69篇
  1999年   58篇
  1998年   29篇
  1997年   29篇
  1996年   17篇
  1995年   19篇
  1994年   18篇
  1993年   21篇
  1992年   42篇
  1991年   35篇
  1990年   25篇
  1989年   32篇
  1988年   20篇
  1987年   18篇
  1986年   25篇
  1985年   23篇
  1984年   24篇
  1982年   16篇
  1980年   16篇
  1979年   36篇
  1978年   19篇
  1977年   19篇
  1976年   17篇
  1975年   24篇
  1974年   18篇
  1973年   27篇
  1972年   22篇
  1971年   26篇
  1970年   31篇
  1968年   15篇
  1967年   23篇
排序方式: 共有2581条查询结果,搜索用时 78 毫秒
91.
Zusammenfassung An einem Material von 32 gesunden, geschlechtsreifen Ratten wird das Ganglion cervicale uteri histologisch untersucht. Besonders in dem apikalen Bereich des Ganglions lassen sich regelmäßig vakuolenhaltige Ganglienzellen nachweisen. Die Zahl dieser Ganglienzellen erfährt in der Schwangerschaft eine statistisch gesicherte Zunahme, was an einem Material von 7 trächtigen und 9 nichtträchtigen Ratten belegt wird. Die Bedingungen für das Auftreten vakuolisierter Ganglienzellen und die Frage nach ihrer Bedeutung müssen in weiteren Untersuchungen geklärt werden.  相似文献   
92.
93.
The International Journal of Life Cycle Assessment - Since 2013, the European Commission (EC) is developing and testing the Product Environmental Footprint (PEF)—a product evaluation method,...  相似文献   
94.
95.
Terephthalic acid based derivatives containing β- and γ-amino acid residues were prepared as antagonists of the leukocyte cell adhesion process that is mediated through the interaction of the very late antigen 4 (VLA-4) and the vascular cell adhesion molecule 1 (VCAM-1). The compounds 2, 1012, 14, and 1617 inhibited the adhesion in a cell based assay in the low and sub micromolar range.  相似文献   
96.
To investigate potential differences in stone composition with regard to the type of Primary Hyperoxaluria (PH), and in relation to the patient’s medical therapy (treatment naïve patients versus those on preventive medication) we examined twelve kidney stones from ten PH I and six stones from four PH III patients. Unfortunately, no PH II stones were available for analysis. The study on this set of stones indicates a more diverse composition of PH stones than previously reported and a potential dynamic response of morphology and composition of calculi to treatment with crystallization inhibitors (citrate, magnesium) in PH I. Stones formed by PH I patients under treatment are more compact and consist predominantly of calcium-oxalate monohydrate (COM, whewellite), while calcium-oxalate dihydrate (COD, weddellite) is only rarely present. In contrast, the single stone available from a treatment naïve PH I patient as well as stones from PH III patients prior to and under treatment with alkali citrate contained a wide size range of aggregated COD crystals. No significant effects of the treatment were noted in PH III stones. In disagreement with findings from previous studies, stones from patients with primary hyperoxaluria did not exclusively consist of COM. Progressive replacement of COD by small COM crystals could be caused by prolonged stone growth and residence times in the urinary tract, eventually resulting in complete replacement of calcium-oxalate dihydrate by the monohydrate form. The noted difference to the naïve PH I stone may reflect a reduced growth rate in response to treatment. This pilot study highlights the importance of detailed stone diagnostics and could be of therapeutic relevance in calcium-oxalates urolithiasis, provided that the effects of treatment can be reproduced in subsequent larger studies.  相似文献   
97.
Antibody-based therapeutics are of great value for the treatment of human diseases. In addition to functional activity, affinity or physico-chemical properties, antibody specificity is considered to be one of the most crucial attributes for safety and efficacy. Consequently, appropriate studies are required before entering clinical trials.

High content protein arrays are widely applied to assess antibody specificity, but this commercial solution can only be applied to final therapeutic antibody candidates because such arrays are expensive and their throughput is limited. A flexible, high-throughput and economical assay that allows specificity testing of IgG or Fab molecules during early discovery is described here. The 384-well microtiter plate assay contains a comprehensive panel of 32 test proteins and uses electrochemiluminescence as readout.

The Protein Panel Profiling (3P) was used to analyze marketed therapeutic antibodies that all showed highly specific binding profiles. Subsequently, 3P was applied to antibody candidates from early discovery and the results compared well with those obtained with a commercially available high content protein chip. Our results suggest that 3P can be applied as an additional filter for lead selection, allowing the identification of favorable antibody candidates in early discovery and thereby increasing the speed and possibility of success in drug development.  相似文献   
98.
99.
The secretion of angiogenic factors by vascular endothelial cells is one of the key mechanisms of angiogenesis. Here we report on the isolation of a new potent angiogenic factor, diuridine tetraphosphate (Up4U) from the secretome of human endothelial cells. The angiogenic effect of the endothelial secretome was partially reduced after incubation with alkaline phosphatase and abolished in the presence of suramin. In one fraction, purified to homogeneity by reversed phase and affinity chromatography, Up4U was identified by MALDI-LIFT-fragment-mass-spectrometry, enzymatic cleavage analysis and retention-time comparison. Beside a strong angiogenic effect on the yolk sac membrane and the developing rat embryo itself, Up4U increased the proliferation rate of endothelial cells and, in the presence of PDGF, of vascular smooth muscle cells. Up4U stimulated the migration rate of endothelial cells via P2Y2-receptors, increased the ability of endothelial cells to form capillary-like tubes and acts as a potent inducer of sprouting angiogenesis originating from gel-embedded EC spheroids. Endothelial cells released Up4U after stimulation with shear stress. Mean total plasma Up4U concentrations of healthy subjects (N = 6) were sufficient to induce angiogenic and proliferative effects (1.34±0.26 nmol L-1). In conclusion, Up4U is a novel strong human endothelium-derived angiogenic factor.  相似文献   
100.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号