全文获取类型
收费全文 | 30544篇 |
免费 | 1585篇 |
国内免费 | 128篇 |
专业分类
32257篇 |
出版年
2022年 | 214篇 |
2021年 | 425篇 |
2020年 | 299篇 |
2019年 | 425篇 |
2018年 | 477篇 |
2017年 | 373篇 |
2016年 | 606篇 |
2015年 | 949篇 |
2014年 | 1027篇 |
2013年 | 1478篇 |
2012年 | 1631篇 |
2011年 | 1487篇 |
2010年 | 1117篇 |
2009年 | 887篇 |
2008年 | 1300篇 |
2007年 | 1245篇 |
2006年 | 1198篇 |
2005年 | 1079篇 |
2004年 | 1094篇 |
2003年 | 1031篇 |
2002年 | 1097篇 |
2001年 | 981篇 |
2000年 | 886篇 |
1999年 | 809篇 |
1998年 | 385篇 |
1997年 | 386篇 |
1996年 | 306篇 |
1995年 | 302篇 |
1994年 | 229篇 |
1993年 | 276篇 |
1992年 | 532篇 |
1991年 | 509篇 |
1990年 | 468篇 |
1989年 | 429篇 |
1988年 | 346篇 |
1987年 | 344篇 |
1986年 | 325篇 |
1985年 | 367篇 |
1984年 | 347篇 |
1983年 | 305篇 |
1982年 | 224篇 |
1981年 | 229篇 |
1980年 | 206篇 |
1979年 | 273篇 |
1978年 | 241篇 |
1977年 | 264篇 |
1976年 | 250篇 |
1975年 | 248篇 |
1974年 | 245篇 |
1973年 | 233篇 |
排序方式: 共有10000条查询结果,搜索用时 7 毫秒
151.
An experimental loop design for the detection of constitutional chromosomal aberrations by array CGH
Joke Allemeersch Steven Van Vooren Femke Hannes Bart De Moor Joris Robert Vermeesch Yves Moreau 《BMC bioinformatics》2009,10(1):380
Background
Comparative genomic hybridization microarrays for the detection of constitutional chromosomal aberrations is the application of microarray technology coming fastest into routine clinical application. Through genotype-phenotype association, it is also an important technique towards the discovery of disease causing genes and genomewide functional annotation in human. When using a two-channel microarray of genomic DNA probes for array CGH, the basic setup consists in hybridizing a patient against a normal reference sample. Two major disadvantages of this setup are (1) the use of half of the resources to measure a (little informative) reference sample and (2) the possibility that deviating signals are caused by benign copy number variation in the "normal" reference instead of a patient aberration. Instead, we apply an experimental loop design that compares three patients in three hybridizations. 相似文献152.
153.
154.
155.
156.
157.
Purothionins are basic polypeptides with antimicrobial properties that are present in the endosperm of wheat and other Gramineae. Susceptibility to crude and electrophoretically purified purothionins among brewing starters has been investigated. Seven yeast strains of Saccharomyces uvarum (syn. carlsbergensis), four strains of Saccharomyces cerevisiae, and four wild strains (Saccharomyces spp.) have been tested in three culture media. All the strains were susceptible to the crude preparation in a yeast extract-glucose medium. Determinations of minimal inhibitory and biocidal concentrations yielded double end points in about half of the assays. The highest sensitivity to purothionins was obtained in malt extract medium. Sensitivity to electrophoretically purified purothionins was of the same order or smaller than to the crude preparation. Possible explanations for this unexpected result are presented. 相似文献
158.
159.
Silvano De Bernardo Manfred Weigele Voldemar Toome Karin Manhart Willy Leimgruber Peter Böhlen Stanley Stein Sidney Udenfriend 《Archives of biochemistry and biophysics》1974,163(1):390-399
Fluorescamine is a useful reagent for the fluorometric assay of primary amines. The extent of the reaction between fluorescamine and primary amines, as well as the fluorescence intensities of the resulting fluorophors depend on pH, solvent composition and reagent concentration. Optimum values for these variables further depend on the amine under study. The influence of these parameters on the fluorogenic reaction of representative amines, and on their fluorophoric derivatives has been investigated, and the results are reported here. 相似文献
160.