首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   1732篇
  免费   216篇
  2021年   22篇
  2019年   15篇
  2016年   38篇
  2015年   47篇
  2014年   56篇
  2013年   71篇
  2012年   80篇
  2011年   83篇
  2010年   59篇
  2009年   40篇
  2008年   63篇
  2007年   58篇
  2006年   53篇
  2005年   63篇
  2004年   50篇
  2003年   54篇
  2002年   47篇
  2001年   41篇
  2000年   68篇
  1999年   39篇
  1998年   29篇
  1997年   21篇
  1996年   21篇
  1995年   19篇
  1994年   29篇
  1993年   26篇
  1992年   23篇
  1991年   28篇
  1990年   33篇
  1989年   32篇
  1988年   33篇
  1987年   34篇
  1986年   34篇
  1985年   34篇
  1984年   21篇
  1983年   14篇
  1982年   20篇
  1981年   14篇
  1979年   18篇
  1978年   19篇
  1977年   16篇
  1976年   14篇
  1975年   16篇
  1974年   27篇
  1973年   21篇
  1972年   23篇
  1971年   20篇
  1970年   15篇
  1967年   16篇
  1966年   17篇
排序方式: 共有1948条查询结果,搜索用时 281 毫秒
1.
2.
Dealing with patients'' sex-related complaints is uncomfortable for many physicians. It can become more comfortable if the physician learns to apply his or her clinical knowledge of sexuality in combination with specific interpersonal interviewing skills. The level of comfort can be increased if the physician accepts his or her professional limitations in providing therapy and knows what other sources of care are available.  相似文献   
3.
4.
5.
6.
7.
8.
9.
10.
Eighteen sows (6 primiparous and 12 multiparous) were allotted randomly within parity to two lactational treatments: litter separation (LS; 6 h/day) plus boar exposure (BE; 1 h/day; N = 14) beginning 8 days before weaning (4 weeks) and no LS + no BE (controls; N = 4). Blood was collected from all sows via indwelling venous catheters at 20-min intervals for 5 h on Days -1, 0, 1, 2 and 3 from start of treatment. Control sows and those exposed to LS + BE not exhibiting oestrus during lactation were resampled on Days -1, 0, 1 and 2 from weaning. All 10 multiparous sows receiving LS + BE exhibited oestrus during lactation, whereas none of the 4 primiparous sows exposed to LS + BE or the 2 control multiparous and 2 control primiparous sows exhibited lactational oestrus. Overall concentrations of LH in serum were higher (P less than 0.05) in sows receiving LS + BE than in control sows during lactation, whereas overall FSH was higher (P less than 0.05) in primiparous than multiparous sows. Number and amplitude of pulses of LH were greater (P less than 0.05) for treated primiparous than multiparous sows during lactation. Oestradiol-17 beta increased (P less than 0.05) in sows during LS + BE and was higher (P less than 0.01) in multiparous sows of this group than control multiparous or treated primiparous sows. Preweaning concentrations of cortisol and progesterone in serum were higher (P less than 0.05) in treated than control sows for multiparous and primiparous animals. In sows resampled at weaning, the number of pulses of LH was greater (P less than 0.05) in treated primiparous than in control sows. Postweaning concentrations of FSH in serum were unaffected by preweaning treatments. It was concluded that (1) litter separation and boar exposure increased basal and pulsatile secretion of LH in multiparous and primiparous sows; (2) lack of ovarian follicular development and oestradiol secretion may preclude expression of oestrus in primiparous sows during lactation, despite elevated concentrations of FSH and LH in serum; and (3) if elevated concentrations of cortisol and progesterone inhibit the onset of oestrous cycles, in response to litter separation and boar exposure during lactation, the effect is limited to primiparous sows.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号