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   37684篇
  免费   2010篇
  国内免费   109篇
耳鼻咽喉   537篇
儿科学   2531篇
妇产科学   836篇
基础医学   4104篇
口腔科学   691篇
临床医学   2365篇
内科学   7489篇
皮肤病学   1243篇
神经病学   1944篇
特种医学   1230篇
外科学   6177篇
综合类   1108篇
一般理论   15篇
预防医学   1821篇
眼科学   1691篇
药学   3139篇
中国医学   189篇
肿瘤学   2693篇
  2023年   267篇
  2022年   619篇
  2021年   1269篇
  2020年   711篇
  2019年   879篇
  2018年   1210篇
  2017年   779篇
  2016年   1069篇
  2015年   985篇
  2014年   1498篇
  2013年   1724篇
  2012年   2536篇
  2011年   2576篇
  2010年   1444篇
  2009年   1203篇
  2008年   1916篇
  2007年   2051篇
  2006年   1811篇
  2005年   1658篇
  2004年   1441篇
  2003年   1301篇
  2002年   1132篇
  2001年   844篇
  2000年   774篇
  1999年   673篇
  1998年   311篇
  1997年   227篇
  1996年   199篇
  1995年   166篇
  1994年   144篇
  1993年   163篇
  1992年   418篇
  1991年   445篇
  1990年   379篇
  1989年   398篇
  1988年   356篇
  1987年   327篇
  1986年   306篇
  1985年   313篇
  1984年   249篇
  1983年   200篇
  1979年   252篇
  1978年   166篇
  1977年   167篇
  1976年   143篇
  1975年   179篇
  1974年   163篇
  1973年   186篇
  1972年   147篇
  1971年   131篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
Behavioural studies were conducted on a random sample of 38 glass bangle workers engaged in various occupations and exposed to high ambient temperature (38.2 +/- 3.4 degrees C) and radiant heat (46.2 +/- 5.1 degrees C) during their work in the glass bangle industries at Firozabad, India. Twenty-two control subjects of similar age and socio-economic status unexposed to heat during their work were also studied for comparison. The digit span test, digit symbol test, Bourdon-Wiersma vigilance test, flicker fusion test and Maudsley personality inventory (MPI) were used to assess the behavioural changes induced by the existing heat stress. The mean scores of immediate memory were much lower in the exposed population than in the controls thereby indicating impairment of immediate memory in the study group. The visuo-motor coordination and vigilance were also significantly affected. Visual perception showed a downward trend among the glass bangle workers, although the MPI test indicated no personality changes.  相似文献   
52.
A study conducted in 1990 revealed that 2% (range 0.6-4.8) of negative blood smears were mislabelled as positive, and 6.7% of positive blood smears were mislabelled as negative. A result of such mislabelling would be inadequate treatment of a large number of patients. Hence the need to look into the training aspect and system of supervision of laboratory technicians. The present system of cross-checking of blood smears at different levels also needs to be reviewed. A study which could address itself to these needs is indicated.  相似文献   
53.
54.
55.
Three cases of chronic rheumatic heart disease with involvement of all four valves are presented. The involvement of tricuspid and pulmonary valves was suspected clinically and was confirmed by two-dimensional echo, Doppler, hemodynamic and angiographic findings. These findings were also verified surgically and histopathologically in 2 cases. One of the cases died after cardiac catheterization; the other 2 cases were treated surgically with success.  相似文献   
56.
57.
58.
59.
Previous work from this laboratory has already indicated that capsaicin, stabilizes the rat lung membrane lipid system on long-term treatment. This stabilization of the membrane is further supported by our present findings that capsaicin pretreatment causes significant inhibition of various chemically induced lipid peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes at both cellular and subcellular levels. Both in vivo and in vitro studies, using whole lung and liver tissue slices and mitochondrial and microsomal fractions, have shown that capsaicin pretreatment inhibits peroxidative changes induced by different chemical irritants such as chloroform, dichloromethane, carbon tetrachloride as well as ferrous sulphate.  相似文献   
60.
To measure myelin basic protein (MBP)-like material in cerebrospinal fluid, we compared two radioimmunoassays, both using the same antiserum to MBP but one using peptide (45-89) as the radioligand and standard (peptide assay), and the other using purified MBP as the radioligand and standard (MBP assay), with respect to their diagnostic sensitivity. Cerebrospinal fluid specimens from 185 patients with definite multiple sclerosis (MS) (n = 27), possible MS (n = 63), probable MS (n = 24), and other neurological disease (n = 71) were analyzed using both assays. The diagnostic sensitivity of the peptide assay was significantly better than that of the MBP assay in those with definite MS (sensitivity 59% and 30%, respectively); there was no significant difference in specificity. The peptide assay also showed better correlation with disease activity than the MBP assay: 14 patients classified as having active MS showed significantly higher sensitivity (78.6% versus 38%, p less than 0.04) when compared to patients with inactive disease. The MBP assay showed no significant difference between these two groups. Besides the increase in sensitivity, the actual molar concentrations of immunoreactive MBP detected using this peptide assay were considerably higher than those found using the MBP assay. These results show that the use of MBP antisera capable of recognizing epitopes present in the carboxyl half of MBP peptide (45-89) results in more sensitive detection of immunoreactive MBP when used with MBP peptide (45-89) as radiolabeled ligand in the assay.  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