全文获取类型
收费全文 | 101篇 |
免费 | 1篇 |
专业分类
综合类 | 3篇 |
畜牧兽医 | 98篇 |
植物保护 | 1篇 |
出版年
2023年 | 1篇 |
2020年 | 1篇 |
2018年 | 1篇 |
2017年 | 1篇 |
2014年 | 2篇 |
2009年 | 2篇 |
2006年 | 1篇 |
2005年 | 1篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2000年 | 1篇 |
1998年 | 6篇 |
1997年 | 9篇 |
1996年 | 6篇 |
1995年 | 2篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 4篇 |
1991年 | 1篇 |
1990年 | 9篇 |
1989年 | 6篇 |
1988年 | 2篇 |
1983年 | 3篇 |
1981年 | 1篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1971年 | 5篇 |
1970年 | 2篇 |
1969年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有102条查询结果,搜索用时 0 毫秒
61.
62.
63.
64.
65.
66.
67.
68.
69.
T Tsutsui F Takahashi T Hori E Kawakami PW Concannon 《Reproduction in domestic animals》2009,44(S2):230-233
The fertile period for natural mating in dogs extends from before ovulation until day 5 post ovulation (PO) and involves a delay in oocyte maturation until 2–3 days PO and viability of secondary oocytes for 48–60 h or more. Spermatozoa do not enter the uterus after vaginal insemination in late oestrus. Cervical closure appears to occur on average 5 days PO, but conception may occur following intrauterine artificial insemination (IUAI) up to 8 days PO. Therefore, the present study was conducted to clarify the duration of fertility of canine ova. Using IUAI at 6, 7, 8 and 9 days PO (n = 5 bitches each) conception rates were 100%, 71.4%, 37.5% and 0%, respectively, with an average litter resorption rate of 30.8%, and with mean litter sizes and times to delivery PO being 4.3 ± 1.6 and 64.3 ± 0.3 days, 4.0 ± 1.4 and 66.3 ± 0.4 days, and 2.5 and 68 days for IUAI at 6, 7 and 8 days, respectively. The high pregnancy rates with IUAI at 6 and 7 days PO confirm that many canine oocytes are fertile at 4–5 days after maturation. The high rate of resorption was presumably because of aging of ova or asynchrony between embryonic development and the intrauterine environment. 相似文献
70.