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   26591篇
  免费   2244篇
  国内免费   44篇
耳鼻咽喉   274篇
儿科学   929篇
妇产科学   717篇
基础医学   3160篇
口腔科学   435篇
临床医学   4137篇
内科学   4813篇
皮肤病学   325篇
神经病学   1996篇
特种医学   1033篇
外国民族医学   3篇
外科学   3134篇
综合类   551篇
一般理论   37篇
预防医学   3254篇
眼科学   750篇
药学   1941篇
中国医学   22篇
肿瘤学   1368篇
  2023年   126篇
  2022年   178篇
  2021年   455篇
  2020年   328篇
  2019年   490篇
  2018年   534篇
  2017年   371篇
  2016年   467篇
  2015年   481篇
  2014年   675篇
  2013年   1062篇
  2012年   1403篇
  2011年   1606篇
  2010年   789篇
  2009年   720篇
  2008年   1410篇
  2007年   1409篇
  2006年   1418篇
  2005年   1383篇
  2004年   1385篇
  2003年   1268篇
  2002年   1186篇
  2001年   622篇
  2000年   634篇
  1999年   586篇
  1998年   310篇
  1997年   276篇
  1996年   257篇
  1995年   244篇
  1994年   208篇
  1993年   195篇
  1992年   440篇
  1991年   432篇
  1990年   412篇
  1989年   418篇
  1988年   367篇
  1987年   343篇
  1986年   342篇
  1985年   332篇
  1984年   284篇
  1983年   242篇
  1982年   180篇
  1981年   140篇
  1979年   195篇
  1978年   171篇
  1977年   142篇
  1976年   130篇
  1974年   162篇
  1973年   144篇
  1972年   129篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
J P Jackson  M A Hutson 《Injury》1986,17(4):251-255
Forty-two severely sprained ankles treated by a cast-brace have been reviewed. This method was devised to avoid the disadvantages of immobilization. Diagnosis was based on the history and clinical signs. Strain films were taken in 31 patients but it is submitted that this investigation may be misleading unless general anaesthesia is used. The results of the treatment by cast-brace compare favourably with those by other methods and it is considered that patients were able to return to sport in a shorter time.  相似文献   
22.
Simulated data using a linear one- and two-compartment body model with different absorption characteristics were used to evaluate the ability of single dose bioavailability data to predict the relationships that exist at steady state. This was done by comparing the confidence intervals obtained from single and multiple dose data sets for the parameters of Tmax, Cmax, and area under the curve from time zero to infinity (AUC0-infinity). As a consequence of Tmax and Cmax decreasing and increasing from single to multiple dosing regimens, the confidence intervals for these parameters reflected these changes. The 90 per cent confidence interval expressed as a percentage of the reference mean increased or decreased for Tmax dependent upon the ratio of Ka test/Ka reference, and decreased for Cmax while the interval for AUC0-infinity exhibited no predictable pattern and appeared to be influenced by the amount of error in the data set. Alteration of either the dosing interval or the fraction absorbed did not affect the pattern of change in the confidence intervals for Tmax and Cmax, but the latter did result in a decrease in the interval for AUC0-infinity. Analysis of the confidence intervals for Tmax, Cmax and AUC0-infinity in bioequivalency studies for quinidine gluconate and procainamide hydrochloride following administration of single and multiple doses to different subjects appeared to be consistent with the patterns observed for the simulated data sets.  相似文献   
23.
BACKGROUND: The MR and pathologic features of hippocampal sclerosis (HS) are well described and include volume decrease and T2-weighted signal increase for MRI, and neuron cell loss and gliosis for pathology. OBJECTIVE: To confirm the established correlation between hippocampal volumes and neuron cell counts, and to study the still controversial association between signal change and gliosis. METHODS: The authors studied 44 patients (22 men and 22 women; mean age at surgery, 37 years) with refractory temporal lobe epilepsy. Quantitative assessment of hippocampal volumes and T2 relaxometry, and neuron and glial cell count in the region CA1 and molecular layer of the dentate gyrus was performed. The proportion of glial fibrillary acidic protein (GFAP)-positive glial cells (reactive astrocytes) was indicated. RESULTS: In a stepwise regression, the ipsilateral hippocampal volume was predicted best by the neuron cell count in the dentate gyrus (p = 0.005, r = 0.4). Hippocampal T2 time, however, was predicted best by the glial cell count in the dentate gyrus (p = 0.01, r = 0.4). None of the other cell counts contributed to either model. In the dentate, 31% of the glial cells were reactive astrocytes, whereas in CA1, 5% were reactive. CONCLUSION: The results confirmed the correlation between hippocampal volumes and neuron cell counts. T2-weighted signal increase in the hippocampus was mainly influenced by gliosis in the dentate gyrus, where a high proportion of glial cells show abnormal activity. This activity may reflect changes important in the development of hippocampal epileptogenicity.  相似文献   
24.
Hypertension (HTN), the leading cause of morbidity and mortality worldwide, is a modifiable risk factor for atherosclerosis. However, all too often, HTN is not well controlled in patients with vascular disease. Studies have demonstrated that patients whose blood pressure is controlled achieve at least a 50% reduction in cardiovascular events compared with similar patients whose blood pressure is not controlled. The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure recently prepared and distributed new guidelines for the management of HTN. This article will highlight the new recommendations for HTN management and how they can be applied to the patient with vascular disease.  相似文献   
25.
26.
27.
The incidence of AIDS among blacks and Hispanics   总被引:3,自引:0,他引:3  
Compared with whites, the acquired immune deficiency syndrome (AIDS) has affected blacks and Hispanics disproportionately. The cumulative incidence (CI) for black men was 2.6, and for Hispanic men 2.5, times the rate for white men. Intravenous (IV) needle use alone does not account for this difference. Not counting IV needle-using cases, the CIs for black and Hispanic men were 1.7 times the CI for white men. Although there were fewer cases in women than men, the white-to-minority disparity was greater for women. The CIs for black and Hispanic women were 12.2 and 8.5 times, respectively, the CI for white women. Prevention programs are urgently needed and should focus on risky behavior (IV needle sharing and receptive anal intercourse), not just risk groups.  相似文献   
28.
29.
30.
Seasonal variations in cryptorchidism.   总被引:2,自引:2,他引:0       下载免费PDF全文
The month of birth of boys undergoing orchidopexy in the Oxfordshire Health District during the years 1974-83 was analysed. A significant seasonal variation with a peak in April was found for those boys operated upon by paediatric surgeons at a young age (0-4). Possible causes of this variation and its relationship to the aetiology of cryptorchidism are discussed.  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