全文获取类型
收费全文 | 2204篇 |
免费 | 169篇 |
国内免费 | 12篇 |
专业分类
2385篇 |
出版年
2024年 | 4篇 |
2023年 | 28篇 |
2022年 | 84篇 |
2021年 | 98篇 |
2020年 | 87篇 |
2019年 | 162篇 |
2018年 | 137篇 |
2017年 | 103篇 |
2016年 | 105篇 |
2015年 | 123篇 |
2014年 | 137篇 |
2013年 | 206篇 |
2012年 | 152篇 |
2011年 | 167篇 |
2010年 | 96篇 |
2009年 | 75篇 |
2008年 | 63篇 |
2007年 | 70篇 |
2006年 | 52篇 |
2005年 | 49篇 |
2004年 | 46篇 |
2003年 | 36篇 |
2002年 | 35篇 |
2001年 | 8篇 |
2000年 | 20篇 |
1999年 | 11篇 |
1998年 | 4篇 |
1997年 | 5篇 |
1996年 | 5篇 |
1995年 | 12篇 |
1994年 | 9篇 |
1993年 | 5篇 |
1992年 | 17篇 |
1991年 | 13篇 |
1990年 | 20篇 |
1989年 | 21篇 |
1988年 | 24篇 |
1987年 | 15篇 |
1986年 | 6篇 |
1985年 | 10篇 |
1984年 | 14篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1980年 | 4篇 |
1979年 | 6篇 |
1978年 | 7篇 |
1975年 | 5篇 |
1974年 | 3篇 |
1966年 | 2篇 |
1956年 | 2篇 |
排序方式: 共有2385条查询结果,搜索用时 0 毫秒
1.
Condon Tom Hakim Abbas Moran Antonio B. Zenteno Blumstein Daniel T. 《Journal of Ethology》2021,39(1):89-96
Journal of Ethology - Animals emit predator-elicited calls in response to potential predation threats. These vocalizations induce a variety of anti-predator behaviors in conspecific receivers... 相似文献
2.
3.
Production of trichothecene and non-trichothecene mycotoxins by Fusarium species isolated from maize in Minnesota 总被引:1,自引:0,他引:1
Eighty-two cultures of Fusarium species isolated in 1986 from moldy maize in Minnesota were each cultured on rice for 4 weeks and found to produce the following mycotoxins: F. graminearum isolates, deoxynivalenol (DON, 4–225 g/g), 3-acetyldeoxynivalenol (3-ADON, 2–4g/g), 15-acetyldeoxynivalenol (15-ADON, 1–35 g/g) and zearalenone (ZEA, 5–4350 g/g); F. moniliforme, fusarin C (detectable amounts to 1000 g/g); F. mòniliforme, F. oxysporum, F. proliferatum and F. subglutinans isolates, moniliformin (15–6775 g/g); F. moniliforme, F. proliferatum, and F. subglutinans isolates, fusaric acid (detectable amounts). Other mycotoxins screened for in each rice sample and not detected were T-2 toxin, HT-2 toxin, neosolaniol, T-2 tetraol, nivalenol, fusarenon-X, scirpenols, alpha and beta trans-zearalenols, wortmannin, and fusarochromanone. The rat feeding bioassay indicated that other, unidentified toxins may be present. 相似文献
4.
K Higuchi A Ogo T Maki M Haji R Takayanagi M Ohashi H Nawata K Kato H Ibayashi 《Endocrinologia japonica》1989,36(6):881-885
The steroid, 19-hydroxyandrost-4-ene-3, 17-dione (19-hydroxyandrostene-dione, 19-OH-A-dione) has been known to enhance the mineralocorticoid action of aldosterone. To investigate the age-related change in the plasma 19-OH-A-dione concentration, plasma 19-OH-A-dione, androst-4-ene-3, 17-dione (A-dione), aldosterone and cortisol of 38 non-hypertensive healthy subjects (18 young men and 20 aged men) measured by specific radioimmunoassays. The basal plasma 19-OH-A-dione and A-dione concentration in aged men was significantly lower than in young men (P less than 0.01). Moreover, there was found to be a positive correlation between plasma 19-OH-A-dione and A-dione (P less than 0.01). On the other hand, plasma aldosterone and cortisol in aged men showed a tendency to decrease, but no statistical significance compared to young men was observed. This study demonstrated that there was an apparent age-related decrease not only in plasma A-dione, but also in plasma 19-OH-A-dione, an amplifier or aldosterone action. 相似文献
5.
A minority of 46,XX true hermaphrodites are positive for the Y-DNA sequence including SRY 总被引:4,自引:0,他引:4
Ken McElreavey Raphaël Rappaport Eric Vilain Nacer Abbas François Richaud Stéphen Lortat-Jacob Roland Berger Maryvonne LeConiat Chafika Boucekkine Kiran Kucheria Samia Temtamy Claire Nihoul-Fekete Raja Brauner Marc Fellous 《Human genetics》1992,90(1-2):121-125
Summary A total of 30 cases of 46,XX true hermaphroditism was analysed for Y-DNA sequences including the recently cloned gene for male testis-determination SRY. In 3 cases, a portion of the Y chromosome including SRY was present and, in 2 cases, was localised, to Xp22 by in situ hybridisation. Since previous studies have shown that the majority of XX males are generated by an X-Y chromosomal interchange, the Xp22 position of the Yp material suggests that certain cases of hermaphroditism can arise by the same meiotic event. The phenotype in the 3 SRY-positive cases may be caused by X-inactivation resulting in somatic mosaicism of testis-determining factor expression giving rise to both testicular and ovarian tissues. Autosomal or X-linked mutation(s) elsewhere in the sex-determining pathway may explain the phenotype observed in the remaining 27 SRY-negative cases. 相似文献
6.
Mycotoxins and Fusarium spp. associated with infected ears of corn in Minnesota. 总被引:1,自引:1,他引:0
下载免费PDF全文
![点击此处可从《Applied microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
H K Abbas C J Mirocha R A Meronuck J D Pokorny S L Gould T Kommedahl 《Applied microbiology》1988,54(8):1930-1933
Five Fusarium species were isolated from the grain of dent corn (Zea mays) selected from 20 of 32 damaged fields in 10 counties in Minnesota on the basis of hyphal growth visible on kernels in the field. Three mycotoxins were identified in the infected ears: zearalenone, deoxynivalenol, and 15-acetyl-deoxynivalenol. This is the first report of the presence of 15-acetyl-deoxynivalenol on corn ears in the field prior to harvest and in combination with deoxynivalenol and zearalenone. Ninety-nine cultures were selected from colonies growing from kernels on an agar medium; 30% of the cultures were F. graminearum, 23% were F. subglutinans, 20% were F. moniliforme, 14% were F. oxysporum, and 12% were F. proliferatum. 相似文献
7.
8.
9.
10.
The authors present a new technic to point out the rheumatoid factor by immunofluorescence and compare this technic and the others to classical technics of agglutination. This technic allows to avoid the absorption of rheumatoid factor in the serological reactions using the immunofluorescence. 相似文献