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   76篇
  免费   40篇
  1篇
综合类   5篇
水产渔业   2篇
畜牧兽医   103篇
植物保护   5篇
  2023年   1篇
  2020年   1篇
  2019年   3篇
  2018年   3篇
  2017年   2篇
  2016年   2篇
  2015年   4篇
  2014年   5篇
  2013年   3篇
  2012年   1篇
  2011年   3篇
  2010年   7篇
  2009年   5篇
  2008年   2篇
  2007年   6篇
  2006年   1篇
  2005年   1篇
  2004年   1篇
  2003年   5篇
  2002年   3篇
  2001年   4篇
  1999年   2篇
  1998年   2篇
  1997年   7篇
  1996年   6篇
  1995年   6篇
  1994年   1篇
  1993年   6篇
  1992年   1篇
  1991年   2篇
  1990年   4篇
  1989年   4篇
  1988年   5篇
  1987年   2篇
  1986年   2篇
  1985年   1篇
  1976年   1篇
  1971年   1篇
排序方式: 共有116条查询结果,搜索用时 15 毫秒
111.
ObjectiveTo evaluate the cardiopulmonary changes induced by intravenous butorphanol administration in guineafowl anesthetized with sevoflurane.Study designProspective experimental trial.AnimalsEight adult guineafowl (Numida meleagris) weighing 1.61 ± 0.49 kg were used for the study.MethodsBirds were anesthetized with sevoflurane and allowed to breathe spontaneously. After endotracheal intubation, end-tidal sevoflurane was adjusted to 1.0 individual sevoflurane MAC that was previously determined in triplicate using a standard bracketing technique. The brachial artery was catheterized for direct pressure measurement and blood sampling. Heart rate and rhythm were monitored by electrocardiography and respiratory rate was recorded. Baseline data were recorded 30 minutes after induction. Then, end-tidal sevoflurane was adjusted to 0.8 individual MAC and after 15 minutes physiologic variables were measured again. Subsequently, butorphanol (4 mg kg?1) was administered intravenously over 10 seconds and physiologic responses were recorded at 1, 5, 10, 15, 20, 30 and 45 minutes after administration.ResultsButorphanol administration was associated with arrhythmias in all birds, including second-degree atrioventricular block, sinus arrest, ventricular and supraventricular tachycardia and ventricular premature complexes. Heart rate and arterial blood pressures decreased significantly 1 minute after butorphanol administration. Two birds developed severe hypotension, apnea and ventricular fibrillation 5 minutes after administration, and one died.Conclusions and clinical relevanceThe butorphanol dose (4 mg kg?1) that produces clinically relevant sevoflurane MAC reduction in guineafowl caused severe adverse cardiopulmonary effects in two birds and was considered unsafe under the conditions used in this study.  相似文献   
112.

We combined two protein-marking enzyme-linked immunosorbent assays (ELISA) with a predator gut content ELISA to monitor the movement and feeding activity of commercially-purchased Hippodamia convergens Guèrin-Mèneville (Coleoptera: Coccinellidae) under realistic field conditions during two field seasons in central Arizona. The protein-marking ELISAs were used to differentiate released H. convergens from the native beetles. Commercially purchased beetles marked with rabbit immunoglobulin G (IgG) were released into cotton fields and chicken IgG marked beetles were released into adjacent cantaloupe fields. Results showed that the total native beetle abundance in each crop was about the same size. The recovery rates after 15 days for the released beetles were less than 1.0% over all the releases, indicating that they dispersed readily from the release site. Of the recaptured beetles containing rabbit IgG (cotton), 82.2% were recovered in cotton and 11.8% moved to cantaloupe. Of those containing chicken IgG (cantaloupe), 66.5% were recovered in cantaloupe and 33.5% moved to cotton. A predator gut content ELISA was used to determine if there were differences in the frequency of predation of released versus indigenous H. convergens on the silverleaf whitefly, Bemisia argentifolii Bellows &; Perring (Homoptera: Aleyrodidae). The proportion of beetles containing whitefly antigens was always higher for the released beetles than for their native counterparts. Our results demonstrate an approach to combine protein marking and predator gut content ELISAs that allows the simultaneous comparison of feeding and intercrop movement of native and commercially-obtained biological control agents.  相似文献   
113.
Analyses of fossil mammal faunas from 2945 localities in the United States demonstrate that the geographic ranges of individual species shifted at different times, in different directions, and at different rates in response to late Quaternary environmental fluctuations. The geographic pattern of faunal provinces was similar for the late Pleistocene and late Holocene, but differing environmental gradients resulted in dissimilar species composition for these biogeographic regions. Modern community patterns emerged only in the last few thousand years, and many late Pleistocene communities do not have modern analogs. Faunal heterogeneity was greater in the late Pleistocene.  相似文献   
114.
The structure of the omasum was compared in 10 water buffalo (Bubalus bubalis), 10 Shorthorn cattle (Bos indicus), 9 Merino sheep (Ovis aries) and 10 cross-bred goats (Capra hircus), and the functional significance of the differences is discussed. The weight of the omasum and area of the internal laminae appeared to be smaller in Brahman cattle than the buffalo and British cattle. When compared in relation to body weight, the omasums of caprid animals were smaller than those of bovids, by a factor of 0.33-0.67 but the omasums of goats were appreciably larger than sheep. The number of laminae ranged from 33 to 35 for the sheep and goats compared with 122 to 169 for the buffalo and cattle. It is suggested that the marked difference in structure of the omasum between the small and large ruminants may influence the food intake of these animals through the effects of this gut compartment on absorption of nutrients and passage of digesta.  相似文献   
115.
The current diagnostic test for Tritrichomonas foetus involves the culture of collected preputial or vaginal samples. In an earlier study, which evaluated sampling tools for use with bulls, it was observed that the sensitivity of the diagnostic test was higher for 2nd samples collected from the right side of the prepuce than it was for samples collected 1st from the left side. The study described in this paper was conducted to evaluate which of these factors was responsible for the effect on diagnostic sensitivity. Twenty-nine bulls infected with T. foetus were repeatedly sampled in a 2-factor cross-over design. Samples taken from the right side of the prepuce were 4 times as likely to be positive as samples taken from the left side (P = 0.03). Other factors did not have a significant effect on the outcome of the diagnostic test. Unexpected factors may affect the sensitivity of the diagnostic test for T. foetus.  相似文献   
116.
Idiopathic hypereosinophilic syndrome (HES) is a rare syndrome for which Rottweilers appear to over-represent the canine cases. A 6-month-old female entire Rottweiler presented with seizures following a traumatic incident. The dog was identified as having a marked, sustained eosinophilia and investigations did not identify an underlying cause. Concurrently, the dog had chronic eosinophilic hepatitis with impaired liver function and mesenteric eosinophilic lymphadenitis. The dog went on to have spontaneous resolution of HES and normal liver function was subsequently documented. To date, the dog is still alive, more than 4 years after initial presentation. The diagnosis of idiopathic HES in Rottweilers may not carry a poor prognosis and the condition may spontaneously resolve, even in cases with documented organ damage.  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