全文获取类型
收费全文 | 858篇 |
免费 | 81篇 |
专业分类
939篇 |
出版年
2022年 | 9篇 |
2021年 | 17篇 |
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 14篇 |
2017年 | 9篇 |
2016年 | 18篇 |
2015年 | 34篇 |
2014年 | 41篇 |
2013年 | 51篇 |
2012年 | 52篇 |
2011年 | 44篇 |
2010年 | 33篇 |
2009年 | 27篇 |
2008年 | 45篇 |
2007年 | 44篇 |
2006年 | 34篇 |
2005年 | 33篇 |
2004年 | 29篇 |
2003年 | 22篇 |
2002年 | 36篇 |
2001年 | 23篇 |
2000年 | 18篇 |
1999年 | 17篇 |
1998年 | 11篇 |
1997年 | 15篇 |
1994年 | 6篇 |
1993年 | 6篇 |
1992年 | 9篇 |
1991年 | 8篇 |
1990年 | 11篇 |
1989年 | 10篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 12篇 |
1985年 | 15篇 |
1984年 | 14篇 |
1983年 | 8篇 |
1982年 | 7篇 |
1981年 | 6篇 |
1979年 | 15篇 |
1975年 | 6篇 |
1974年 | 15篇 |
1973年 | 5篇 |
1972年 | 10篇 |
1971年 | 7篇 |
1970年 | 6篇 |
1969年 | 5篇 |
1967年 | 5篇 |
1966年 | 9篇 |
排序方式: 共有939条查询结果,搜索用时 0 毫秒
931.
G. Ramakrishnan A. Banerji M.S. Chadha 《Phytochemistry》1974,13(10):2317-2318
932.
Mark K. Brannon J. Muse Davis Jonathan R. Mathias Chris J. Hall Julia C. Emerson Philip S. Crosier Anna Huttenlocher Lalita Ramakrishnan Samuel M. Moskowitz 《Cellular microbiology》2009,11(5):755-768
Pseudomonas aeruginosa is an opportunistic human pathogen that can cause serious infection in those with deficient or impaired phagocytes. We have developed the optically transparent and genetically tractable zebrafish embryo as a model for systemic P. aeruginosa infection. Despite lacking adaptive immunity at this developmental stage, zebrafish embryos were highly resistant to P. aeruginosa infection, but as in humans, phagocyte depletion dramatically increased their susceptibility. The virulence of an attenuated P. aeruginosa strain lacking a functional Type III secretion system was restored upon phagocyte depletion, suggesting that this system influences virulence through its effects on phagocytes. Intravital imaging revealed bacterial interactions with multiple blood cell types. Neutrophils and macrophages rapidly phagocytosed and killed P. aeruginosa , suggesting that both cell types play a role in protection against infection. Intravascular aggregation of erythrocytes and other blood cells with resultant circulatory blockage was observed immediately upon infection, which may be relevant to the pathogenesis of thrombotic complications of human P. aeruginosa infections. The real-time visualization capabilities and genetic tractability of the zebrafish infection model should enable elucidation of molecular and cellular details of P. aeruginosa pathogenesis in conditions associated with neutropenia or impaired phagocyte function. 相似文献
933.
Yaron J. Lidor Feng J. Xu Otoniel Martínez-Maza George J. Olt Jeffrey R. Marks Andrew Berchuck Sundaram Ramakrishnan Jonathan S. Berek Robert C. Bast Jr. 《Experimental cell research》1993,207(2)
Normal and neoplastic epithelial cells produce growth factors that can affect cells from different lineages. Epithelial ovarian cancers produce M-CSF and IL-6. In the present study, production of these cytokines has been measured in the apparently normal epithelial cells from which epithelial ovarian neoplasms are thought to arise. Epithelial cells from the surface of premenopausal human ovaries were established in short-term cultures. The cells bound anti-cytokeratin antibodies and exhibited characteristic epithelial morphology by light and transmission electron microscopy. M-CSF and IL-6 were detected in supernatants from cultures of these cells, using assays specific for each factor. Cytokine levels were comparable to those in supernatants from ovarian and breast cancer cell lines. M-CSF expression could also be demonstrated by immunohistochemical analysis with specific rabbit heteroantiserum. Thus, M-CSF and IL-6 are produced constitutively by normal as well as by neoplastic ovarian epithelium. 相似文献
934.
935.
936.
A total of 171 plant species used by the Nishis, the Hill M iris, the Sulungs, and the Apatanis of Lower Subansiri district of Arunachal Pradesh in northeastern India; 12 animal species used by the Nishis were identified. Of the total plant species recorded 38% of the total were leafy vegetables and 28% were edible fruits. Others were used for food, liquor, medicine, household goods, traditional dresses, dyes, tattoos, fish and animal poisons, or for salt extraction. The Sulungs use starch obtained from the pith ofMetroxylon sagu as a staple food. The extensive use of wild plants and animals suggests that the tribes of northeastern India rely heavily on forest resources. The importance of conserving these in the light of rapid conversion of rainforests is emphasized. 相似文献
937.
938.
939.