全文获取类型
收费全文 | 856718篇 |
免费 | 98185篇 |
国内免费 | 355篇 |
专业分类
955258篇 |
出版年
2016年 | 9248篇 |
2015年 | 12768篇 |
2014年 | 15200篇 |
2013年 | 22037篇 |
2012年 | 24171篇 |
2011年 | 24680篇 |
2010年 | 16595篇 |
2009年 | 15495篇 |
2008年 | 22061篇 |
2007年 | 23284篇 |
2006年 | 21791篇 |
2005年 | 20965篇 |
2004年 | 20950篇 |
2003年 | 20338篇 |
2002年 | 19836篇 |
2001年 | 35048篇 |
2000年 | 35561篇 |
1999年 | 28531篇 |
1998年 | 10462篇 |
1997年 | 10991篇 |
1996年 | 10555篇 |
1995年 | 10075篇 |
1994年 | 9985篇 |
1993年 | 9912篇 |
1992年 | 25058篇 |
1991年 | 24805篇 |
1990年 | 24603篇 |
1989年 | 24074篇 |
1988年 | 22489篇 |
1987年 | 21550篇 |
1986年 | 20179篇 |
1985年 | 20733篇 |
1984年 | 17300篇 |
1983年 | 15107篇 |
1982年 | 11772篇 |
1981年 | 10887篇 |
1980年 | 10168篇 |
1979年 | 16989篇 |
1978年 | 13342篇 |
1977年 | 12457篇 |
1976年 | 11845篇 |
1975年 | 13005篇 |
1974年 | 13853篇 |
1973年 | 13595篇 |
1972年 | 12805篇 |
1971年 | 11326篇 |
1970年 | 9903篇 |
1969年 | 9564篇 |
1968年 | 8854篇 |
1967年 | 7714篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
A T Kravchenko R G Latypova V M Morpgova A A Movsesiants 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1980,(11):28-30
The study of the effect of gamma globulin introduced in different doses (0.5 and 0.25 ml/mg) in combination with Fermi rabies vaccine (observations on humans were made) and with cerebral rabies vaccine inactivated by UV irradiation (in animal experiments) demonstrated that the injection of the higher doses of gamma globulin resulted in lower geometrical mean of antibody titers. Therefore, in combined administration of rabies vaccine and gamma globulin for postexposure rabies prevention it is advisable to reduce the dose of gamma globulin by one-half. 相似文献
992.
Assignment of the human homologue of Pim-1, a mouse gene implicated in leukemogenesis,to the pter-q12 region of chromosome 6 总被引:2,自引:0,他引:2
Summary Viral leukemogenesis in mice is frequently initiated by proviral activation of a highly conserved cellular gene called Pim-1. Here we report the chromosomal localization of the human homologue by Southern blot analyses of DNAs obtained from human-rodent somatic cell hybrids. The single copy human homologue was assigned to the 6pter-q12 segment. 相似文献
993.
994.
995.
996.
997.
998.
999.
RNA and DNA in developing retinae: comparison of a normal with the degenerating retinae of C3H mice 总被引:4,自引:2,他引:2
R N Lolley 《Journal of neurochemistry》1973,20(1):175-182
Abstract— The Nucleic acids were measured in developing retinae of normal (DBA) mice and those afflicted with an inherited degenerative disease (C3H). The content of RNA in normal and C3H retinae increased to a maximum at 5 days of postnatal age. Thereafter, that of C3H retinae declined to a value lower than the normal. The content of DNA in normal and C3H retinae was maximal at 10 and 5 days of postnatal age, respectively. By 20 days, it declined in both retinae to nearly adult values. The DNA/RNA ratio of normal adult retinae was about 3, while that of C3H adult retinae was nearly 1–5. It is proposed that the photoreceptor cells possess a smaller cytoplasmic volume and a larger DNA/RNA ratio than the cells of the inner retina. The loss of DNA in developing normal and C3H retinae appears to result from cellular death. It was calculated that approximately 1 million cells in normal and 6 million cells in C3H retinae disappear during development. Cellular death in C3H retinae may not be restricted to the photoreceptor population. 相似文献
1000.
During an ultrastructural study of small-intestinal mucosa from a patient suffering from alpha-chain disease organisms were identified within the epithelial cytoplasm which showed the fine structural features of the coccidian group. Though coccidiosis is well recognized as causing a diarrhoeal and often lethal illness in animals it has been neglected as a cause of disease in man. Thus this finding may be significant and warrants further investigation into its possible role in the pathogenesis of alpha-chain disease. 相似文献