全文获取类型
收费全文 | 500篇 |
免费 | 45篇 |
国内免费 | 1篇 |
专业分类
546篇 |
出版年
2021年 | 11篇 |
2020年 | 4篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 6篇 |
2015年 | 16篇 |
2014年 | 16篇 |
2013年 | 31篇 |
2012年 | 25篇 |
2011年 | 23篇 |
2010年 | 7篇 |
2009年 | 8篇 |
2008年 | 17篇 |
2007年 | 19篇 |
2006年 | 21篇 |
2005年 | 21篇 |
2004年 | 16篇 |
2003年 | 18篇 |
2002年 | 17篇 |
2001年 | 12篇 |
2000年 | 13篇 |
1999年 | 12篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 6篇 |
1994年 | 5篇 |
1992年 | 8篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 7篇 |
1988年 | 10篇 |
1987年 | 11篇 |
1986年 | 4篇 |
1984年 | 9篇 |
1983年 | 7篇 |
1982年 | 6篇 |
1980年 | 4篇 |
1978年 | 9篇 |
1977年 | 8篇 |
1976年 | 5篇 |
1974年 | 4篇 |
1973年 | 9篇 |
1972年 | 5篇 |
1971年 | 4篇 |
1970年 | 5篇 |
1969年 | 4篇 |
1967年 | 5篇 |
1966年 | 8篇 |
1949年 | 5篇 |
1941年 | 3篇 |
排序方式: 共有546条查询结果,搜索用时 15 毫秒
71.
ABSTRACT: BACKGROUND: Affinity-Purification Mass-Spectrometry (AP-MS) provides a powerful means of identifyingprotein complexes and interactions. Several important challenges exist in interpreting theresults of AP-MS experiments. First, the reproducibility of AP-MS experimental replicatescan be low, due both to technical variability and the dynamic nature of protein interactions inthe cell. Second, the identification of true protein-protein interactions in AP-MS experimentsis subject to inaccuracy due to high false negative and false positive rates. Severalexperimental approaches can be used to mitigate these drawbacks, including the use ofreplicated and control experiments and relative quantification to sensitively distinguish trueinteracting proteins from false ones. RESULTS: To address the issues of reproducibility and accuracy of protein-protein interactions, weintroduce a two-step method, called ROCS, which makes use of Indicator Proteins to selectreproducible AP-MS experiments, and of Confidence Scores to select specific protein-proteininteractions. The Indicator Proteins account for measures of protein identification as well asprotein reproducibility, effectively allowing removal of outlier experiments that contributenoise and affect downstream inferences. The filtered set of experiments is then used in theProtein-Protein Interaction (PPI) scoring step. Prey protein scoring is done by computing aConfidence Score, which accounts for the probability of occurrence of prey proteins in thebait experiments relative to the control experiment, where the significance cutoff parameter isestimated by simultaneously controlling false positives and false negatives against metrics offalse discovery rate and biological coherence respectively. In summary, the ROCS methodrelies on automatic objective criterions for parameter estimation and error-controlledprocedures. We illustrate the performance of our method by applying it to five previously published AP-MS experiments, each containing well characterized protein interactions,allowing for systematic benchmarking of ROCS. We show that our method may be used onits own to make accurate identification of specific, biologically relevant protein-proteininteractions or in combination with other AP-MS scoring methods to significantly improveinferences. CONCLUSIONS: Our method addresses important issues encountered in AP-MS datasets, making ROCS a verypromising tool for this purpose, either on its own or especially in conjunction with othermethods. We anticipate that our methodology may be used more generally in proteomicsstudies and databases, where experimental reproducibility issues arise. The method isimplemented in the R language, and is available as an R package called "ROCS", freelyavailable from the CRAN repository http://cran.r-project.org/. 相似文献
72.
Pontillo J Wu D Ching B Hudson S Genicot MJ Gao Y Ewing T Fleck BA Gogas K Aparicio A Wang H Wen J Wade WS 《Bioorganic & medicinal chemistry letters》2008,18(23):6151-6155
The design synthesis and SAR of a series of chiral ring-constrained norepinephrine reuptake inhibitors with improved physicochemical properties is described. Typical compounds are potent (IC(50)s<10 nM), selective against the other monoamine transporters, weak CYP2D6 inhibitors (IC(50)s>1 microM) and stable to oxidation by human liver microsomes. In addition, the compounds exhibit a favorable polarity profile. 相似文献
73.
Limitations to vegetation establishment and abundance in biofiltration swales (also called biofilters or bioswales), vegetated storm-water facilities intended to improve runoff water quality, was studied through field monitoring and greenhouse experimentation. The various environmental factors influencing vegetation and organic litter abundance was investigated in eight bioswales in western Washington state, including three that were retrofitted. A nested 4×4 factorial greenhouse experiment tested the response of four turfgrass species commonly seeded in bioswales to three inundation regimes plus a control. In the greenhouse experiment and in the field, persistent inundation significantly suppressed germination and growth. Field monitoring further revealed that heavy shade overwhelms all other environmental factors. Where light is adequate, vegetation and organic litter biomass is strongly and inversely related to the proportion of time bioswales are inundated above 2.5-cm depth during the driest time of year (summer). For most bioswales, flow velocity and hydraulic loading during storm events appear too large to permit sedimentation of silt and clay particles, even with dense vegetation and abundant organic litter. Thus, herbaceous vegetation abundance may not provide a good indication of bioswale treatment performance, and actual storm-water treatment may be much poorer than is generally anticipated from previous studies. 相似文献
74.
75.
76.
77.
John A. Ewing 《BMJ (Clinical research ed.)》1956,2(4991):503-506
78.
An analysis of polygenes affecting wing shape on chromosome 3 in Drosophila melanogaster. 总被引:1,自引:0,他引:1
Loci on the third chromosome of Drosophila melanogaster that affect an index of wing shape were mapped, using recombinant isogenic lines, with transposable elements as markers. Many genes with small subequal effects are dispersed along the whole chromosome. Their alleles act nearly additively in heterozygotes. They have small correlated effects on leg shape, but no detectable effects on halteres. Small negative net interactions occur over most of the chromosome. The data set of 519 recombinant isogenic lines can be explained reasonably well by two models. One model posits an indefinitely large number of loci with no interactions. The other model posits 11 loci with additive effects whose sum equals the total phenotypic range and with large positive and negative interactions that nearly cancel each other. 相似文献
79.
Patty A. Gray 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(1):85-87
In Pursuit of the Siberian Shaman. Anya Bernstein, director; 2006. 75 mins., color, in Russian and Buryat with English subtitles. Distributor: DER, 101 Morse St., Watertown, MA 02472. 相似文献
80.
Michiel?B?HaesekerEmail author Evelien?Pijpers Nicole?HTM?Dukers-Muijrers Patty?Nelemans Christian?JPA?Hoebe Cathrien?A?Bruggeman Annelies?Verbon Valère?J?Goossens 《Immunity & ageing : I & A》2013,10(1):30