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   156篇
  免费   17篇
  国内免费   1篇
儿科学   9篇
妇产科学   1篇
基础医学   18篇
口腔科学   1篇
临床医学   6篇
内科学   10篇
神经病学   38篇
特种医学   5篇
外科学   27篇
综合类   1篇
预防医学   23篇
药学   34篇
肿瘤学   1篇
  2023年   1篇
  2021年   10篇
  2020年   1篇
  2019年   3篇
  2018年   3篇
  2017年   4篇
  2016年   5篇
  2015年   1篇
  2014年   12篇
  2013年   6篇
  2012年   7篇
  2011年   6篇
  2010年   8篇
  2009年   7篇
  2008年   10篇
  2007年   7篇
  2006年   15篇
  2005年   10篇
  2004年   9篇
  2003年   8篇
  2002年   11篇
  2001年   2篇
  2000年   4篇
  1999年   3篇
  1998年   1篇
  1993年   1篇
  1992年   1篇
  1988年   1篇
  1987年   1篇
  1986年   6篇
  1985年   2篇
  1984年   1篇
  1982年   1篇
  1981年   1篇
  1980年   1篇
  1979年   3篇
  1978年   1篇
排序方式: 共有174条查询结果,搜索用时 15 毫秒
1.
2.
Observations of the epizootic of bovine ephemeral fever which occurred in Saudi Arabia during 1996 are presented. The investigations included the collection of epidemiological data from affected farms and the testing of sera for antibodies to the virus. The authors report a mean morbidity rate of 50% and a mean case fatality rate of 0.3%. Of the infected cattle, 4% were affected by recumbency, the majority of these recovered (89%). The clinical signs observed in affected cattle were uniform throughout the region concerned. The features of the outbreak, obtained through field investigations, were considered in relation to the ecological and meteorological conditions which were prevalent at the time. The outbreak occurred during the summer months (May to October) in the central and eastern regions of Saudi Arabia, with the initial infection reported at the Al-Ahsa oasis. Farms which were subsequently affected were all reported to possess areas of stagnant water suitable for the reproduction of the vectors of the disease (Culicoides spp. and mosquitoes). To conclude, the authors discuss precautions to prevent future outbreaks of bovine ephemeral fever in Saudi Arabia.  相似文献   
3.
Converging evidence from clinical, preclinical, neuroimaging, and genetic research implicates dopamine neurotransmission in the pathophysiology of attention deficit hyperactivity disorder (ADHD). The in vivo neuroreceptor imaging evidence also suggests alterations in the dopamine system in ADHD; however, the nature and behavioral significance of those have not yet been established. Here, we investigated striatal dopaminergic function in ADHD using [11C]raclopride PET with a d-amphetamine challenge. We also examined the relationship of striatal dopamine responses to ADHD symptoms and neurocognitive function. A total of 15 treatment-free, noncomorbid adult males with ADHD (age: 29.87±8.65) and 18 healthy male controls (age: 25.44±6.77) underwent two PET scans: one following a lactose placebo and the other following d-amphetamine (0.3 mg/kg, p.o.), administered double blind and in random order counterbalanced across groups. In a separate session without a drug, participants performed a battery of neurocognitive tests. Relative to the healthy controls, the ADHD patients, as a group, showed greater d-amphetamine-induced decreases in striatal [11C]raclopride binding and performed more poorly on measures of response inhibition. Across groups, a greater magnitude of d-amphetamine-induced change in [11C]raclopride binding potential was associated with poorer performance on measures of response inhibition and ADHD symptoms. Our findings suggest an augmented striatal dopaminergic response in treatment-naive ADHD. Though in contrast to results of a previous study, this finding appears consistent with a model proposing exaggerated phasic dopamine release in ADHD. A susceptibility to increased phasic dopamine responsivity may contribute to such characteristics of ADHD as poor inhibition and impulsivity.  相似文献   
4.
5.
6.
A severe outbreak of contagious ecthyma (orf) is described in sheep in Saudi Arabia. In some of the affected sheep, the condition was highly aggravated by myiasis which appeared to have been favoured by the abundance of flies during the hot season. The outbreak is discussed in relation to the epidemiology of the disease in Saudi Arabia.  相似文献   
7.
Epizootiological aspects of peste des petits ruminants (PPR) and rinderpest in sheep and goats in Saudi Arabia are examined. The presence of PPR has been suspected on occasions, but virus isolation has been successful only once. Information regarding PPR and rinderpest in sheep and goats in Saudi Arabia is scarce. The only survey conducted indicated that neither disease is endemic in the country.  相似文献   
8.
9.
A large ectopic liver nodule connected to the greater omentum had undergone infarction and separation because of torsion of its connecting stalk and was the cause of acute abdominal pain and elevated liver enzymes in a young female child. At laparotomy for a suspected perforated appendicitis, a hemorrhagic peritoneal fluid was found, together with an intraperitoneal solid mass lying freely in the right iliac fossa. The definitive diagnosis was obtained by histopathology. This is the first known such reported case.  相似文献   
10.
A retrospective study was undertaken to examine domestic ruminant sera for Rift Valley fever (RVF) virus antibodies. The sera were collected between 1992 and 1995 from cattle, sheep and goats from various locations in Saudi Arabia. The standard capture enzyme-linked immunosorbent assay system was employed to detect specific RVF antibodies in the animals and the results indicated an absence of RVF antibodies. This finding confirms the assumption that Saudi Arabia was free from RVF up until at least 1995 and most probably before the 2000 epidemic. The finding also confirms that RVF was not endemic in Saudi Arabia.  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