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   6128篇
  免费   556篇
  国内免费   32篇
耳鼻咽喉   20篇
儿科学   306篇
妇产科学   175篇
基础医学   1132篇
口腔科学   148篇
临床医学   731篇
内科学   1434篇
皮肤病学   147篇
神经病学   255篇
特种医学   403篇
外科学   622篇
综合类   140篇
一般理论   3篇
预防医学   491篇
眼科学   59篇
药学   408篇
中国医学   2篇
肿瘤学   240篇
  2021年   55篇
  2018年   82篇
  2015年   64篇
  2014年   75篇
  2013年   162篇
  2012年   169篇
  2011年   167篇
  2010年   151篇
  2009年   132篇
  2008年   182篇
  2007年   226篇
  2006年   207篇
  2005年   171篇
  2004年   146篇
  2003年   191篇
  2002年   144篇
  2001年   142篇
  2000年   157篇
  1999年   173篇
  1998年   147篇
  1997年   149篇
  1996年   163篇
  1995年   118篇
  1994年   135篇
  1993年   128篇
  1992年   148篇
  1991年   144篇
  1990年   147篇
  1989年   179篇
  1988年   152篇
  1987年   148篇
  1986年   136篇
  1985年   125篇
  1984年   107篇
  1983年   74篇
  1982年   66篇
  1981年   71篇
  1980年   82篇
  1979年   104篇
  1978年   80篇
  1977年   71篇
  1976年   79篇
  1975年   73篇
  1974年   62篇
  1972年   64篇
  1971年   65篇
  1970年   67篇
  1965年   60篇
  1963年   54篇
  1960年   70篇
排序方式: 共有6716条查询结果,搜索用时 15 毫秒
71.
The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%);  相似文献   
72.
73.
74.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA.  相似文献   
75.
76.
Immunoglobulin G, appearing after several months in the serum of a recipient of a successful kidney transplant from a closely matched sibling donor, was demonstrated to progressively inhibit unidirectional mixed lymphocyte cultures when donor lymphocytes were used either in responding or stimulating cell populations. The active recipient IgG had no effect in cultures in which donor cells were not used, nor did IgG obtained from other individuals show nonspecific inhibitory effects on cultures containing donor cells. It is suggested that the MLC inhibitory immunoglobulin may serve an immunoregulatory function after renal transplantation.  相似文献   
77.
One hundred and thirty-two Scottish families, representing the majority of currently known cases in this country with at least one living subject affected by DMD (110) or BMD (22), were studied with a series of cDNA probes excluding the 3' region of the gene (probes 10-14). Using mainly HindIII digested DNA from affected males, 89 patients showed deletions which ranged from 1 to 32 HindIII fragments in size. Two patients were also detected with exon duplications. Abnormalities were found to be particularly concentrated in the area of probe cDNA 8, with 56 patients being deleted for at least one of the fragments detected by this probe. A second smaller concentration of deletions was found with probe 1-2a which showed 16 deletions and two duplications. The endpoints of cDNA deletions or duplications were determined with a maximum variability of one HindIII fragment in 83 patients, while the remaining eight patients had a single deletion endpoint defined. The deletions found in two of our patients appear to conflict with the previously stated exon order at the 5' end of the gene. Although no specific deletion patterns were apparent for DMD, the deletions found in 13 of the BMD patients all included the most proximal (10 kb) fragment detected by probe 8.  相似文献   
78.
79.
A 7 year old boy is described with moderate learning disability, facial dysmorphism, and a de novo duplication of chromosome 2 (q11.2-q21). There are few published reports of proximal 2q duplication, and none reporting direct de novo duplication for this exact region.  相似文献   
80.
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