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   250909篇
  免费   14886篇
  国内免费   662篇
林业   23393篇
农学   13986篇
基础科学   2946篇
  42161篇
综合类   25315篇
农作物   17180篇
水产渔业   16743篇
畜牧兽医   94960篇
园艺   6313篇
植物保护   23460篇
  2021年   2461篇
  2020年   2863篇
  2019年   3646篇
  2018年   3889篇
  2017年   4213篇
  2016年   4711篇
  2015年   4289篇
  2014年   5662篇
  2013年   16242篇
  2012年   5894篇
  2011年   7757篇
  2010年   7214篇
  2009年   7769篇
  2008年   7198篇
  2007年   6271篇
  2006年   6969篇
  2005年   6163篇
  2004年   6080篇
  2003年   5840篇
  2002年   5258篇
  2001年   5603篇
  2000年   5322篇
  1999年   5118篇
  1998年   4107篇
  1997年   4181篇
  1996年   3865篇
  1995年   4452篇
  1994年   3831篇
  1993年   3549篇
  1992年   4114篇
  1991年   4302篇
  1990年   4076篇
  1989年   4064篇
  1988年   3631篇
  1987年   3669篇
  1986年   3550篇
  1985年   3882篇
  1984年   3611篇
  1983年   3457篇
  1982年   2864篇
  1981年   2767篇
  1980年   2744篇
  1979年   3217篇
  1978年   2860篇
  1977年   2685篇
  1976年   2492篇
  1974年   2656篇
  1973年   2641篇
  1972年   2423篇
  1971年   2387篇
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
91.
Since the International Society of Veterinary Acupuncture (IVAS) was founded in 1974, acupuncture (AP) has received greater acceptance by veterinary professionals throughout the world. This article introduces some important animal diseases that respond well to AP therapy. These include resuscitation of small animals, treatment of anoestrous gilts and sows, bovine reproductive disease, canine vertebral problems and equine backpain, etc. Conventional medicine considers these to be difficult cases to treat. Veterinarians have become more aware of the benefits of AP especially for those diseases, thanks to the efforts of experienced practitioners and scientists, and the many published reports on veterinary AP that have introduced some good indications for AP therapy in veterinary practice. Possible mechanisms behind the effectiveness of AP are discussed. This article aims to introduce veterinarians to good indications for AP to initiate their interest in the practice of AP. Although this is a rapidly expanding field, a long march must begin with one step. We wish this article to be the shoes for such a march. For more information on veterinary AP, contact IVAS , P.O. Box 1478, Longmont, CO.. 80502, USA (http://www.ivas.org), or your national veterinary acupuncture society (http://www.komvet.at/ ivadkom/vapsocs.htm).  相似文献   
92.
Two serological tests (indirect immunofluorescence and enzyme-linked immunosorbent assay) were developed for the detection of fetal antibody to Chlamydia psittaci. Fetal blood and thoracic fluid from 126 field cases of suspected ovine chlamydial abortion were examined using both tests. Placenta and fetal tissues (lung, liver, and kidney) from the same animals were also examined by the following conventional diagnostic methods: isolation in McCoy cells, detection of chlamydial lipopolysaccharide (LPS), modified Ziehl-Nielsen staining, and direct fluorescent antibody staining of chlamydia in frozen cryostat sections. Seventy cases were positive by fetal serology, and of these, 68 were also positive by isolation and/or LPS detection. The remaining 56 cases had negative fetal serology, and of these, 39 were positive by isolation and/or LPS detection. Results indicate that fetal serology, although less sensitive than either isolation in McCoy cells or detection of chlamydial LPS antigen, may be of particular use when placenta is not available.  相似文献   
93.
94.
95.
    
Ohne Zusammenfassung  相似文献   
96.
Star catalogues     
  相似文献   
97.
98.
99.
100.
The feet of three two-humped camels (Camelus bactrianus), one lama (Lama glama) and four alpacas (Lama pacos) from zoos and a circus in the Netherlands were examined for the mange-mite Choroptes bovis. Mites were found on two of the camels, the lama, and three of the alpacas. On one camel and one alpaca small mange lesions on the feet were present. This is the first report of Chorioptes bovis and chorioptic mange in the two-humped camel.  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