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   23篇
  免费   0篇
林业   2篇
综合类   2篇
畜牧兽医   18篇
园艺   1篇
  2020年   1篇
  2019年   2篇
  2014年   1篇
  2010年   3篇
  2007年   2篇
  2003年   2篇
  2002年   1篇
  2000年   1篇
  1997年   2篇
  1996年   2篇
  1993年   1篇
  1991年   1篇
  1990年   1篇
  1988年   1篇
  1986年   2篇
排序方式: 共有23条查询结果,搜索用时 296 毫秒
11.
12.
13.
为研究酒制熟地黄炮制工艺过程中梓醇的变化趋势和变化机理,利用HPLC检测酒制熟地黄炮制过程中不同时间点梓醇的含量,并利用FT-IR结合变温附件获取梓醇在不同温度点的红外光谱信息。结果表明,酒制熟地黄炮制过程中,梓醇含量整体呈下降趋势,但不同时间段梓醇含量下降率不同。梓醇含量下降的原因是其热稳定性较低,在温度90~100℃之间,其结构就发生变化。所以,生地黄产地加工焙干时,温度不能太高,以免梓醇含量下降;熟地黄炮制过程中,时间不能太短,以免“火候”不到。  相似文献   
14.
15.
An 8-year-old mare, with a foal at foot, was inseminated on foal heat with frozen semen, with the resultant pregnancy lost between days 34 and 41. The right ovary developed a large anovulatory follicle that was non-responsive to multiple doses of ovulating agents. The follicle eventually appeared to luteinise, although plasma progesterone concentrations did not reflect this. Another follicle developed, responded to GnRH and resulted in a pregnancy from frozen semen that went to term with a healthy foal. When the mare was examined after foaling, the structure on the right ovary appeared to be a granulosa cell tumour; the left ovary was smaller than normal and non-functional. Surgical removal of the right ovary before increasing photoperiod resulted in a return to function of the left ovary and a pregnancy to frozen semen on the second cycle following removal. Figures showing concentrations of inhibin, progesterone, androstenedione, oestradiol and testosterone are presented for this entire period. Unusual ovarian activity in the mare might be a prelude to the development of a granulosa cell tumour.  相似文献   
16.
Modified White's solution (1 g HgCl2/l H2O) is widely used to surface disinfest bark beetles of their phoretic fungi. We investigated the effectiveness of this solution at disinfesting adult Ips pini from its associated ophiostomatoid fungi. A treatment for 1, 4 or 8 min does not completely rid beetles of phoretic fungi, but does substantially reduce the amount of fungi they carry externally. Sterilizing with modified White's solution caused limited mortality (<16%).  相似文献   
17.
18.
Objective: To investigate the presence of Salmonella Dublin in Queensland cattle.
Design: An epidemiological study using diagnostic laboratory information and farm records.
Procedure: Outbreaks of gastroenteritis or pneumonia in calves, and abortions and enteritis in cows were routinely investigated for the presence of salmonellae. Where S Dublin was isolated, attempts were made to gather further epidemiological information.
Results: Prior to 1983 only two outbreaks of S Dublin have been recorded in Queensland dairy cattle. In 1983 S Dublin abortions were diagnosed in dairy heifers introduced from southern Australia to south-east Queensland. Sampling indicated that at least 10% of the 500 introduced heifers were faecal excretors of S Dublin. On 3 of the 7 farms from which S Dublin was recorded, infection spread to other cattle that were in contact. From February 1985 to February 1996, 29 outbreaks of S Dublin in cattle occurred on 29 farms (28 in south east Queensland and 1 in north Queensland). Calves were primarily affected. Continuing outbreaks were confirmed on only 4 of these 29 farms. On 15 farms S Dublin infections were associated with the purchase of infected calves or cows, while another farm adjoined 2 previously infected farms. No source of S Dublin was evident for the other 13 farms, where histories were often inadequate.
Conclusion: There has been a marked increase in S Dublin outbreaks in Queensland dairy cattle since 1983. Introduction of S Dublin carrier and aborting dairy heifers from southern Australia, where S Dublin is not uncommon, was associated with the initial outbreaks.  相似文献   
19.
20.
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