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   9109篇
  免费   1102篇
  国内免费   41篇
耳鼻咽喉   106篇
儿科学   239篇
妇产科学   251篇
基础医学   1368篇
口腔科学   162篇
临床医学   1030篇
内科学   1759篇
皮肤病学   106篇
神经病学   754篇
特种医学   467篇
外国民族医学   10篇
外科学   1298篇
综合类   261篇
一般理论   5篇
预防医学   823篇
眼科学   206篇
药学   650篇
中国医学   9篇
肿瘤学   748篇
  2022年   78篇
  2021年   158篇
  2020年   92篇
  2019年   162篇
  2018年   195篇
  2017年   148篇
  2016年   135篇
  2015年   174篇
  2014年   211篇
  2013年   287篇
  2012年   393篇
  2011年   460篇
  2010年   227篇
  2009年   228篇
  2008年   389篇
  2007年   397篇
  2006年   380篇
  2005年   354篇
  2004年   324篇
  2003年   316篇
  2002年   323篇
  2001年   297篇
  2000年   292篇
  1999年   249篇
  1998年   131篇
  1997年   96篇
  1996年   107篇
  1995年   99篇
  1994年   87篇
  1993年   76篇
  1992年   221篇
  1991年   193篇
  1990年   169篇
  1989年   170篇
  1988年   171篇
  1987年   169篇
  1986年   187篇
  1985年   184篇
  1984年   108篇
  1983年   114篇
  1982年   78篇
  1979年   122篇
  1978年   100篇
  1977年   75篇
  1976年   96篇
  1975年   72篇
  1974年   99篇
  1973年   117篇
  1972年   86篇
  1970年   73篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
Partial nephrectomy is the mainstay of treatment for localized kidney cancer. A proportion of patients are upstaged post-operatively to locally advanced di  相似文献   
3.
Calcified tissue is a common component of atherosclerotic plaques, and occurs most often in mature plaques. The process of calcification is a poorly understood risk factor that may contribute to a plaque's vulnerability to sudden rupture. In this study a solid-state imaging sequence, termed single-point imaging (SPI), was used to observe calcification directly in ex vivo atherosclerotic plaques. Standards were used to validate the ability of (31)P SPI to detect and differentiate calcification from crystalline cholesterol, phospholipids, and other plaque components. After suitable experimental parameters were found, human carotid specimens obtained by endarterectomy were imaged ex vivo by (31)P solid-state imaging and standard (1)H methods. In contrast to (1)H imaging methods, (31)P imaging detected only the calcification in the plaque.  相似文献   
4.
To evaluate morbidity associated with surgical lengthening of the gastrocnemius, medical records were reviewed retrospectively for 126 patients (mean age, 49.7 years; range, 8-78 years) who had undergone open gastrocnemius recession. Ten patients had isolated recession; 116 had gastrocnemius recession with an additional foot or ankle procedure on the ipsilateral limb. During a mean follow-up period of 19 months (range, 6-50 months), all patients were examined for any postoperative complications associated with the recession. Complications were defined as the presence of postoperative infection, wound dehiscence, nerve problems, decreased muscle strength, scar problems, or calcaneus gait (overlengthening). Uncomplicated outcome was defined as absence of all these complications and return to regular activity, both occurring during a follow-up of at least 6 months. Postsurgical complications developed in 9 (6%) of the 126 patients: 6 (4%) had scar problems, 2 (1.33%) had wound dehiscence, 2 (1.33%) had infection, 3 (2%) had nerve problems, and 1 (0.67%) developed complex regional pain syndrome. No patient complained of either a limp or gait disturbance. Neither persistent decrease in muscle strength nor calcaneus gait was seen. These data suggest that the open gastrocnemius recession procedure has low associated morbidity.  相似文献   
5.
In chronic myeloid leukaemia, CD34(+) stem/progenitor cells appear resistant to imatinib mesylate (IM) in vitro and in vivo. To investigate the underlying mechanism(s) of IM resistance, it is essential to quantify Bcr-Abl kinase status at the stem cell level. We developed a flow cytometry method to measure CrkL phosphorylation (P-CrkL) in samples with <10(4) cells. The method was first validated in wild-type (K562) and mutant (BAF3) BCR-ABL(+) as well as BCR-ABL(-) (HL60) cell lines. In response to increasing IM concentration, there was a linear reduction in P-CrkL, which was Bcr-Abl specific and correlated with known resistance. The results were comparable to those from Western blotting. The method also proved to be reproducible with small samples of normal and Ph(+) CD34(+) cells and was able to discriminate between Ph(-), sensitive and resistant Ph(+) cells. This assay should now enable investigators to unravel the mechanism(s) of IM resistance in stem cells.  相似文献   
6.
7.
8.
Sex and racial predilection, social history, and histology were analyzed in a biopsy-proven adenocarcinoma of the lower esophagus/esophagogastric junction collected over a 5-year period in two teaching institutions with different patient populations. Adenocarcinoma occurred in 11% of patients with biopsy-proven esophageal cancer. The disease occurred only in males at one center, and in a 7:1 ratio of males to females at the other center. Clear racial predilection was seen, since 12 of 13 patients with adenocarcinoma of the esophagus were white, whereas less than 20% of patients with squamous carcinoma of the esophagus were white. The finding of Barrett's epithelium in eight of the 13 cases strongly supports the theory that in white males, Barrett's epithelium is a precursor lesion of adenocarcinoma of the esophagus/esophagogastric junction.  相似文献   
9.
The computed tomography findings in two cases of gastrointestinal superinfection by opportunistic organisms in acquired immune deficiency syndrome are presented. Findings included thickening of the mucosal folds and the bowel wall in the small intestine and colon associated with cytomegalovirus and cryptosporidiosis. These cases indicate that it is important to look carefully at the gastrointestinal tract when performing computed tomography in this group of patients. Unsuspected bowel pathology may be demonstrated, or disease may be confirmed in clinically suspected cases.  相似文献   
10.
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