全文获取类型
收费全文 | 188篇 |
免费 | 9篇 |
专业分类
林业 | 1篇 |
3篇 | |
综合类 | 131篇 |
畜牧兽医 | 58篇 |
植物保护 | 4篇 |
出版年
2018年 | 3篇 |
2017年 | 1篇 |
2016年 | 3篇 |
2015年 | 2篇 |
2014年 | 3篇 |
2013年 | 11篇 |
2012年 | 2篇 |
2010年 | 3篇 |
2009年 | 2篇 |
2008年 | 1篇 |
2006年 | 3篇 |
2004年 | 1篇 |
2001年 | 1篇 |
1999年 | 2篇 |
1998年 | 12篇 |
1997年 | 2篇 |
1996年 | 3篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 44篇 |
1990年 | 53篇 |
1989年 | 20篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1931年 | 1篇 |
1930年 | 1篇 |
1918年 | 1篇 |
1914年 | 3篇 |
1907年 | 2篇 |
排序方式: 共有197条查询结果,搜索用时 15 毫秒
31.
32.
Presumptive Sry-negative XX sex reversal in a llama with multiple congenital anomalies. 总被引:1,自引:0,他引:1
M L Drew V N Meyers-Wallen G M Acland C L Guyer D N Steinheimer 《Journal of the American Veterinary Medical Association》1999,215(8):1134-1139
Multiple congenital abnormalities of the external genitalia consistent with XX sex reversal were detected in a juvenile llama. The llama had a typical female karyotype (74, XX) and did not have a Y chromosome, but a minute chromosome was detected. To determine whether a piece of Y chromosome containing the Sry gene might be located in a small translocation, DNA analysis by polymerase chain reaction was performed; the Sry gene was not detected. Histologic examination revealed ovarian tissue, whereas testicular tissue was not found. External genitalia were partially masculinized, indicating that the urogenital sinus, genital tubercle, and genital swellings had been exposed to androgens during development, although the dam had not received exogenous androgens. Testicular tissue in the ovaries may have been undetected or had regressed prior to birth, as has been reported in sex reversal in mice. 相似文献
33.
Guyer MF 《Science (New York, N.Y.)》1930,71(1833):169-176
34.
35.
36.
37.
38.
39.
40.