全文获取类型
收费全文 | 3913篇 |
免费 | 326篇 |
国内免费 | 2篇 |
专业分类
4241篇 |
出版年
2023年 | 25篇 |
2022年 | 39篇 |
2021年 | 60篇 |
2020年 | 52篇 |
2019年 | 59篇 |
2018年 | 66篇 |
2017年 | 84篇 |
2016年 | 126篇 |
2015年 | 175篇 |
2014年 | 220篇 |
2013年 | 247篇 |
2012年 | 324篇 |
2011年 | 290篇 |
2010年 | 215篇 |
2009年 | 166篇 |
2008年 | 229篇 |
2007年 | 248篇 |
2006年 | 198篇 |
2005年 | 195篇 |
2004年 | 174篇 |
2003年 | 153篇 |
2002年 | 174篇 |
2001年 | 46篇 |
2000年 | 47篇 |
1999年 | 51篇 |
1998年 | 46篇 |
1997年 | 31篇 |
1996年 | 39篇 |
1995年 | 30篇 |
1994年 | 34篇 |
1993年 | 23篇 |
1992年 | 19篇 |
1991年 | 27篇 |
1990年 | 29篇 |
1989年 | 30篇 |
1988年 | 32篇 |
1987年 | 17篇 |
1986年 | 13篇 |
1985年 | 17篇 |
1984年 | 16篇 |
1983年 | 13篇 |
1982年 | 12篇 |
1981年 | 13篇 |
1980年 | 9篇 |
1979年 | 12篇 |
1978年 | 10篇 |
1977年 | 8篇 |
1976年 | 15篇 |
1974年 | 7篇 |
1973年 | 13篇 |
排序方式: 共有4241条查询结果,搜索用时 7 毫秒
1.
2.
D. Haferburg R. Hommel H.-P. Kleber S. Kluge G. Schuster H.-J. Zschiegner 《Engineering in Life Science》1987,7(4):353-356
A rhamnolipid released by Pseudomonas aeruginosa 196 Aa into the culture medium reduced the number of local lesions induced by tobacco mosaic virus on leaves of the hypersensitive host Nicotiana glutinosa L. by up to 90%. The content of potato virus X in the systemically infected host Nicotiana tabacum L. ‘Samsun’ is decreased in inoculated as well as in secondarily infected leaves by up to 50%. In a smaller degree red clover mottle virus is influenced in the systemic host Pisum sativumconvar.speciosum (Dierb.) Alef ‘Nadja’. 相似文献
3.
4.
The effects of an extracellular microbial glycolipid, the interfacial active lactonic sophoroselipid, and of Triton X-100 on strains of Acinetobacter calcoaceticus are compared. Sophoroselipid diminished growth rates on n-heptadecane. Both surfactants led to the excretion of enzyme activities into the culture medium. Sophoroselipid increased the release of cytoplasmic malate dehydrogenase whereas in presence of Triton X-100 the quinoprotein glucose dehydrogenase was also excreted in large amounts. 相似文献
5.
6.
7.
Daniel Hohl Barbara Ruf Olano Pierre A. de Viragh Marcel Huber Carol J. Detrisac Urs W. Schnyder Dennis R. Roop 《Differentiation; research in biological diversity》1993,54(3):25-34
Abstract. In this study we analyzed the expression patterns of loricrin in various species and tissues using immunohistochemistry, immunoblotting and Northern blots. Loricrin is a glycine-, serine- and cysteine-rich protein expressed very late in epidermal differentiation in the granular layers of normal mouse and human epidermis. Later on in differentiation, loricrin becomes cross-linked as a major component into the cornified cell envelope by the formation of Nɛ -(γ-glutamyl)lysine isopeptide bonds. This process either occurs directly or by the intermediate accumulation in L-keratohyaline granules of mouse epidermis and human acrosyringia. Loricrin was identified in all mammalian species analyzed by virtue of its highly conserved carboxy-terminal sequences revealing an electric mobility of ∼60 kDa in rodents, rabbit and cow and of ∼35 kDa in lamb and human on sodium dodecyl sulfate polyacrylamide gel electrophoresis. Loricrin is expressed in the granular layer of all mammalian orthokeratinizing epithelia tested including oral, esophageal and fore-stomach mucosa of rodents, tracheal squamous metaplasia of vitamin A deficient hamster and estrogen induced squamous vaginal epithelium of ovary ectomized rats. Loricrin is also expressed in a few parakeratinizing epithelia such as BBN [N-butyl-N-(4–hydroxybutyl)nitrosamine]-induced murine bladder carcinoma and a restricted subset of oral and single vaginal epithelial cells in higher mammals. Our results provide further evidence that the program of squamous differentiation in internal epithelia of the upper alimentary tract in rodents and higher mammals differ remarkably. In addition, we also have noted the distinct distribution patterns of human loricrin and involucrin, another major precursor protein of the cornified cell envelope. 相似文献
8.
9.
10.