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   748篇
  免费   26篇
  国内免费   4篇
耳鼻咽喉   2篇
儿科学   2篇
妇产科学   1篇
基础医学   86篇
口腔科学   11篇
临床医学   104篇
内科学   192篇
神经病学   80篇
特种医学   22篇
外科学   109篇
预防医学   19篇
眼科学   3篇
药学   57篇
中国医学   3篇
肿瘤学   87篇
  2022年   12篇
  2021年   22篇
  2020年   10篇
  2019年   24篇
  2018年   24篇
  2017年   15篇
  2016年   13篇
  2015年   9篇
  2014年   18篇
  2013年   22篇
  2012年   45篇
  2011年   43篇
  2010年   42篇
  2009年   15篇
  2008年   40篇
  2007年   43篇
  2006年   37篇
  2005年   38篇
  2004年   42篇
  2003年   38篇
  2002年   35篇
  2001年   18篇
  2000年   12篇
  1999年   10篇
  1998年   15篇
  1997年   10篇
  1996年   7篇
  1995年   7篇
  1994年   5篇
  1993年   6篇
  1992年   6篇
  1991年   8篇
  1990年   4篇
  1989年   4篇
  1988年   6篇
  1987年   5篇
  1986年   7篇
  1985年   4篇
  1984年   4篇
  1982年   2篇
  1979年   3篇
  1978年   6篇
  1977年   4篇
  1973年   4篇
  1972年   3篇
  1971年   8篇
  1970年   6篇
  1969年   6篇
  1968年   4篇
  1967年   2篇
排序方式: 共有778条查询结果,搜索用时 9 毫秒
111.
112.
We report a case of a culture-negative osteomyelitis in which our newly developed real-time polymerase chain reaction (PCR) could differentiate Staphylococcus aureus from Staphylococcus epidermidis. This is the first report that described the application of this novel assay to an orthopedics clinical sample. This assay may be useful for other clinical culture-negative cases in a combination with a broad-spectrum assay as a rapid microorganism identification method.  相似文献   
113.
Post-natal development of the circadian rhythm of hypothalamic content of corticotrophin-releasing factor (CRF) was examined in male and female rats, separately. CRF activity was estimated by the intrapituitary injection technique. The circadian rhythm of the CRF content observed at the third week was without any noticeable sex difference: both male and female rats began their circadian rhythm with higher values in the afternoon than in the morning. Male rats maintained this pattern up to maturity. In contrast, female rats showed a marked change at ages of fifth to sixth week: the CRF rhythm in female rats changed to a female pattern, with higher values in the morning than in the afternoon. During this period, the vaginal opening occurred concurrently with a marked afternoon rise in the plasma corticosterone, characteristic of mature female rats. On the other hand, no essential difference could be observed between male and female rats in the developmental change in the circadian rhythm of locomotor activity. These results indicate that a sex difference in the CRF rhythm is not essentially related to the process of sex differentiation in the central nervous system, but is rather related to changes in ovarian activity following the onset of puberty.  相似文献   
114.
115.
116.
117.
118.
A 44-year-old woman developed jaundice and was diagnosed as stage II of primary biliary cirrhosis (PBC). She showed a severely high total cholesterol level. This article focuses on atypical presentations of PBC and the need to test the total cholesterol level of PBC patients.  相似文献   
119.
Release of GABA is controlled by presynaptic GABA receptor type B (GABA(B)) autoreceptors at GABAergic terminals. However, there is no direct evidence that GABA(B) autoreceptors are activated by GABA release from their own terminals, and precise profiles of GABA(B) autoreceptor-mediated suppression of GABA release remain unknown. To explore these issues, we performed multiple whole-cell, patch-clamp recordings from layer V rat insular cortex. Both unitary inhibitory and excitatory postsynaptic currents (uIPSCs and uEPSCs, respectively) were recorded by applying a five-train depolarizing pulse injection at 20 Hz. In connections from both fast-spiking (FS) and non-FS interneurons to pyramidal cells, the GABA(B) receptor antagonist CGP 52432 had little effect on the initial uIPSC amplitude. However, uIPSCs, responding to later pulses, were effectively facilitated. This CGP 52432-induced facilitation was prominent in the fourth uIPSCs, which were evoked 150 ms after the first uIPSC. The facilitation of uIPSCs was accompanied by an increase in the paired-pulse ratio. In addition, analysis of the coefficient of variation suggests the involvement of presynaptic mechanisms in CGP 52432-induced uIPSC facilitation. Paired-pulse stimulation (interstimulus interval = 150 ms) of presynaptic FS cells revealed that the second uIPSC was also facilitated by CGP 52432, which had little effect on the amplitude and interevent interval of miniature IPSCs. In contrast, uEPSCs, responding to all five stimulations of a presynaptic pyramidal cell, were less affected by CGP 52432. These results suggest that a single presynaptic action potential is sufficient to activate GABA(B) autoreceptors and to suppress GABA release in the cerebral cortex.  相似文献   
120.
A 29-year-old man had been diagnosed with an anterior mediastinal cyst 6 years earlier and was undergoing follow-up. At a follow-up visit, a newly developed cystic lesion was found in the middle mediastinum; therefore, the anterior mediastinal cyst and the middle mediastinal cyst were resected by thoracoscopic surgery. It was observed that the middle mediastinal cyst originated from the thoracic duct, and the thoracic duct was clipped. Pathologically, the diagnosis was a thymic cyst of the anterior mediastinum and a thoracic duct cyst of the middle mediastinum. The patient developed chylothorax after surgery, and a second thoracoscopic operation was performed. It revealed that part of the clipping of the caudal thoracic duct was incomplete, and leakage of chyle was observed. Hence, the clipping was performed again. The course after the second surgery was good. Thoracic duct cysts are rare even among mediastinal cysts and thus require caution due to their tendency to expand.  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