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   26208篇
  免费   1391篇
  国内免费   65篇
耳鼻咽喉   371篇
儿科学   2056篇
妇产科学   624篇
基础医学   3029篇
口腔科学   457篇
临床医学   1439篇
内科学   4849篇
皮肤病学   1035篇
神经病学   1143篇
特种医学   956篇
外科学   3891篇
综合类   926篇
一般理论   12篇
预防医学   1302篇
眼科学   1315篇
药学   2139篇
中国医学   141篇
肿瘤学   1979篇
  2023年   149篇
  2022年   386篇
  2021年   743篇
  2020年   419篇
  2019年   496篇
  2018年   722篇
  2017年   473篇
  2016年   673篇
  2015年   591篇
  2014年   926篇
  2013年   1099篇
  2012年   1561篇
  2011年   1657篇
  2010年   908篇
  2009年   720篇
  2008年   1261篇
  2007年   1331篇
  2006年   1154篇
  2005年   1086篇
  2004年   975篇
  2003年   908篇
  2002年   812篇
  2001年   730篇
  2000年   684篇
  1999年   598篇
  1998年   246篇
  1997年   179篇
  1996年   145篇
  1995年   136篇
  1994年   116篇
  1993年   132篇
  1992年   359篇
  1991年   390篇
  1990年   347篇
  1989年   362篇
  1988年   314篇
  1987年   280篇
  1986年   272篇
  1985年   282篇
  1984年   219篇
  1983年   181篇
  1979年   241篇
  1978年   159篇
  1977年   148篇
  1976年   135篇
  1975年   163篇
  1974年   154篇
  1973年   176篇
  1972年   138篇
  1971年   122篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
81.
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   
82.
83.
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   
84.
85.
86.
87.
This paper examines the role of selective serotonin reuptake inhibitors (SSRIs) in the treatment of hepatitis-C virus (HCV) patients who have developed interferon-α induced depression. A 2-year data analysis of HCV psychiatric liaison clinic has been undertaken. The diagnosis, treatment, and progress of those patients who were treated with interferon-α (INF-α) are reported. 53 of the 78 patients enrolled at the HCV Clinic and treated with INF-α were referred for psychiatric consultation. Six patients developed major depressive illness following INF therapy. They were all treated with SSRIs and they made full recovery. This is a significant observation and is concordant with other studies. Its biochemical ramifications are presented. It is concluded that INF-induced depression is fully reversible. A hypothesis is proposed that SSRIs modulate the neuro-protective neurotoxic ratio by possibly inhibiting the indole-2,3-dioxygenase induction of the kynurenine pathway.  相似文献   
88.
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   
89.
90.
Influence of carbohydrates on the immunogenicity and immunocontraceptive potential of zona pellucida glycoproteins has been investigated in rabbits. Porcine zonae pellucidae, following deglycosylation with trifluoromethane-sulfonic acid, retained significant immunogenic potential, as shown by the ability to generate antibodies which cross-reacted with the heterologous antigen. Antibody response, however, was much stronger against the native zona glycoproteins, thereby suggesting that both carbohydrate and protein moieties contribute to the overall immunogenicity of the zona pellucida antigens. Contraceptive efficacy of active immunization with the deglycosylated zona antigens, when evaluated by mating experiments, demonstrated inhibition of fertility in all immunized rabbits. Normal ovarian functions were disrupted in these animals, as revealed by the reduction in ovarian weights and gross impairment of folliculogenesis. Flushing of the oviducts of the immunized animals yielded a markedly reduced number of ova ovulated in response to hCG administration, none of which were fertilizable. Results collectively suggest that active heteroimmunization with deglycosylated zona pellucida antigens is effective in reducing fertility in rabbits.  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