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   68篇
  免费   8篇
综合类   10篇
畜牧兽医   64篇
植物保护   2篇
  2023年   1篇
  2022年   1篇
  2020年   1篇
  2019年   1篇
  2017年   1篇
  2016年   5篇
  2015年   3篇
  2014年   3篇
  2013年   15篇
  2011年   2篇
  2010年   2篇
  2009年   5篇
  2007年   1篇
  2006年   2篇
  2005年   2篇
  2001年   3篇
  1999年   3篇
  1998年   5篇
  1997年   3篇
  1996年   4篇
  1995年   1篇
  1994年   1篇
  1993年   2篇
  1991年   3篇
  1989年   2篇
  1988年   1篇
  1979年   3篇
排序方式: 共有76条查询结果,搜索用时 15 毫秒
71.
Three dogs were referred to The Queen's Veterinary School Hospital at University of Cambridge for chronic behavioural or locomotor disorders associated with pain. All three had been unsuccessfully treated with conventional analgesics, including non-steroidal anti-inflammatory drugs, glucocorticoids and opiate agonists, prior to referral, with minimal or no response. They were investigated by neurological examination plus conventional ancillary diagnostic tests and therapeutic drug trials. Ruling out other causes of pain and applying previously well-described criteria, each case was diagnosed as consistent with neuropathic pain, a poorly recognised condition in domestic dogs. Treatment with the tricyclic antidepressant drug, amitriptyline, or the antiepileptic drug, gabapentin, resulted in either a dramatic improvement or full resolution of clinical signs in all cases.  相似文献   
72.
The main objectives of the present study were to determine the ultrastructural modifications occurring in the oocyte during late folliculogenesis and to estimate pre-antral follicle population in buffalo. Half the collected ovaries were fixed and prepared for optic microscopy; the antral follicles from the other ovaries were measured and individually punctured. The cumulus–oocyte complexes (COCs) were processed for transmission electron microscopy. The number of pre-antral follicles in buffalo ovaries was estimated at 19 819 structures. Cumulus–oocyte complexes derived from 1-mm antral follicle had an eccentrical nucleus and compact corona radiata , ooplasm vilosities were fully embedded in zona pellucida (ZP) and a well-defined junction could be observed. Mitochondria were predominantly round and well distributed in ooplasm, as were small lipid vacuoles. In COCs derived from 2-mm antral follicles, the initial formation of perivitelline space was observed. The nucleus was peripherally located and the number of pleomorphic mitochondria increased. Cortical granules were clustered at oocyte periphery and lipid vacuoles increased in number and size. In COCs derived from 6-mm antral follicles, the organelles were located mainly in the perinuclear region. Golgi complexes and smooth endoplasmic reticulum (SER) were more developed. Mitochondria migrated to the cortical region and lipid vacuoles migrated to the medullar region. In COCs derived from 10-mm antral follicles, the lipid vacuoles coalesced and occupied the medullar region of the oocyte, together with a well-developed SER. Mitochondria were pleomorphic and located at the oocyte periphery. In conclusion, the morphological differences described in this paper could be responsible for some functional differences observed in in vitro embryo production and follicular dynamics for buffalo, when compared with cattle.  相似文献   
73.
74.
Over a 25-month period 8118 blood samples were assayed for the presence of the serum pregnancy specific-protein B (PSPB) and progesterone (P4) concentrations on three Hungarian large-scale dairy farms. Pregnancy (n = 4085) was checked by BioPRYN assay at 30-36 days post-insemination (PI). Samples from all cows that tested not pregnant and from cows with an optical density (OD) reading in the BioPRYN test that was between 0% and 30% above the cutoff OD value were tested for serum P4 concentration. According to serum P4 concentration, cows were assigned to three categories: high (>4 ng/ml), medium (2-4 ng/ml) and low (<2 ng/ml) serum progesterone. The authors predicted a presumed (low) or possible (medium) late embryonic loss (LEL) or maintenance of the pregnancy (high). A total of 710 LELs were detected (17.4%) and 31.8% of them were predicted because of a low OD value at 30-36 days after insemination. Lower PSPB serum level significantly refers for LEL (p < 0.0001). The prediction rate for the true embryonic loss was 31.8% when OD cutoff from 0% to + 30% of cutoff was examined while it was 62.5% when the threshold was OD cutoff of 0% to 10% of cutoff. The authors conclude that BioPRYN was useful for prediction of a part of LEL in dairy cows and serum P4 concentration in these cows related to the rate of LEL.  相似文献   
75.
Several photometric measurements of Venus made from the Pioneer Venus orbiter and probes indicate that solar near-ultraviolet radiation is being absorbed throughout much of the main cloud region, but little above the clouds or within the first one or two optical depths. Radiative transfer calculations were carried out to simulate both Pioneer Venus and ground-based data for a number of proposed cloud compositions. This comparison rules out models invoking nitrogen dioxide, meteoritic material, and volatile metals as the source of the ultraviolet absorption. Models involving either small ( approximately 1 micrometer) or large ( approximately 10 micrometers) sulfur particles have some serious difficulties, while ones invoking sulfur dioxide gas appear to be promising.  相似文献   
76.
A 14-week-old kitten had a history of vomiting, diarrhoea and pyrexia, all of which resolved without treatment. Three weeks later the kitten developed a violent non-productive dry cough. Thoracic radiographs revealed pneumothorax and nodular alveolar disease. Aelurostrongylus abstrusus larvae and intracellular Gram-negative bacilli were seen in bronchial wash fluid and pleural exudate, and Salmonella Typhimurium was cultured from both fluids but not from faeces. Therapy included unilateral closed-tube thoracostomy, enrofloxacin and fenbendazole. Historical signs were compatible with gastrointestinal salmonellosis and secondary broncho-pneumonia. Seeding of the lungs with salmonellae may have occurred as a result of migration of A abstrusus from a gastro-intestinal tract residually infected or colonised by S Typhimurium. Alternatively, the development of lungworm infection in the cat may have activated quiescent S Typhimurium pulmonary granulomata from bacteraemia secondary to gastro-intestinal salmonellosis. Two years after diagnosis the cat was reportedly in good health.  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