全文获取类型
收费全文 | 1221篇 |
免费 | 216篇 |
国内免费 | 1篇 |
专业分类
1438篇 |
出版年
2019年 | 13篇 |
2017年 | 17篇 |
2016年 | 23篇 |
2015年 | 25篇 |
2014年 | 44篇 |
2013年 | 50篇 |
2012年 | 62篇 |
2011年 | 54篇 |
2010年 | 40篇 |
2009年 | 28篇 |
2008年 | 35篇 |
2007年 | 45篇 |
2006年 | 46篇 |
2005年 | 37篇 |
2004年 | 42篇 |
2003年 | 43篇 |
2002年 | 42篇 |
2001年 | 36篇 |
2000年 | 45篇 |
1999年 | 33篇 |
1998年 | 18篇 |
1997年 | 25篇 |
1996年 | 14篇 |
1995年 | 14篇 |
1994年 | 16篇 |
1993年 | 18篇 |
1992年 | 24篇 |
1991年 | 33篇 |
1990年 | 37篇 |
1988年 | 15篇 |
1987年 | 18篇 |
1986年 | 21篇 |
1985年 | 14篇 |
1984年 | 21篇 |
1983年 | 15篇 |
1982年 | 14篇 |
1981年 | 14篇 |
1980年 | 16篇 |
1979年 | 16篇 |
1978年 | 21篇 |
1977年 | 12篇 |
1976年 | 12篇 |
1975年 | 18篇 |
1974年 | 25篇 |
1973年 | 24篇 |
1972年 | 23篇 |
1971年 | 18篇 |
1970年 | 18篇 |
1969年 | 12篇 |
1968年 | 16篇 |
排序方式: 共有1438条查询结果,搜索用时 0 毫秒
1.
2.
3.
4.
5.
6.
Susan F. Hirsch 《American anthropologist》2000,102(1):169-170
Just Words: Law, Language, and Power. John M. Conley and William M. O'Barr. Chicago: The University of Chicago Press, 1998. 168 pp. 相似文献
7.
Human immunodeficiency virus neutralizing antibodies recognize several conserved domains on the envelope glycoproteins. 总被引:67,自引:42,他引:25 下载免费PDF全文
D D Ho M G Sarngadharan M S Hirsch R T Schooley T R Rota R C Kennedy T C Chanh V L Sato 《Journal of virology》1987,61(6):2024-2028
Serum neutralizing antibodies against the human immunodeficiency virus were frequently detected in infected individuals, and low or absent serum neutralizing titers correlated with poor prognosis. Multiple diverse human immunodeficiency virus isolates were found to exhibit similar susceptibility to neutralization by a panel of human seropositive sera, suggesting that neutralizing antibodies are largely directed against conserved viral domains. Furthermore, utilizing antisera raised against a library of synthetic env peptides, four regions which are important in the neutralization process have been identified within both human immunodeficiency virus envelope glycoproteins (gp41 and gp120). Three of these are in conserved domains and should be considered for inclusion in a candidate vaccine. 相似文献
8.
Quantitative assessment of vaginal microflora during use of tampons of various compositions. 总被引:10,自引:1,他引:9 下载免费PDF全文
A B Onderdonk G R Zamarchi M L Rodriguez M L Hirsch A Muoz E H Kass 《Applied microbiology》1987,53(12):2774-2778
Although the effect of vaginal tampons on the microbial flora during menstruation has recently been studied by several investigators, quantitative effects attributable to particular tampon fibers have received less attention. The purposes of the present study were (i) to determine and then to compare the effects of polyacrylate rayon tampons and viscose rayon tampons on the normal vaginal flora, (ii) to compare quantitative bacterial counts obtained from these tampons with those obtained from concomitant vaginal swabs, and (iii) to determine whether either of these tampon types alters the vaginal microflora when compared with the microflora in the same women using all-cotton tampons or external catamenial pads. Tampon and swab samples were obtained at predetermined times from 18 women for an average of seven menstrual cycles. Samples consisting of swabs from women wearing menstrual pads were compared with swab and tampon samples taken at predetermined times during the menstrual cycle from women using cotton, polyacrylate rayon, or viscose rayon tampons. Samples were analyzed for total aerobic, facultative, and anaerobic bacterial counts. Statistical evaluation of the results indicated that, on the whole, total bacterial counts decreased during menstruation and that the numbers of bacteria in tampons tended to be lower than those in swab samples taken at the same time. The tampon type had little effect on the vaginal microflora. 相似文献
9.
The combination of two-dimensional mini gel electrophoresis with the 'western blot' technique proves to be a powerful tool in characterizing lymphoid cells. By testing for kappa and lambda immunoglobulin light chains we were able to differentiate between mono-, oligo-, and polyclonal B-cell diseases. The distribution of the lambda isotypes of 24 cases with chronic lymphocytic B-cell leukemia (B-CLL) tested was not random when compared to the distribution of the lambda light chains in B-lymphocytes of normal persons. This might implicate a genetic link between the lambda loci (chromosome 22) and the development of the lambda-CLL. 相似文献
10.
H R Hirsch 《Journal of theoretical biology》1984,111(1):61-79
General relationships between the distribution of cell doubling times and the growth pattern of an initially synchronized cell population are applied to the model proposed by Smith and Martin (1973) in which the mitotic cycle or "B" phase is preceded by a random-exit resting "A" state. Results show that culture synchronization decays so rapidly as to be virtually unobservable unless the time spent by a cell in the B phase is at least equal to that spent in the A state. If synchronization persists over several mitotic cycles, the growth pattern is determined to a much greater extent by variation in the duration of the B phase than by the probability of exit from the A state. Accordingly the growth pattern of a cell population, like the doubling time distribution which governs the pattern, is of limited usefulness in detecting the existence of a resting state. 相似文献