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   24915篇
  免费   8313篇
  国内免费   185篇
耳鼻咽喉   223篇
儿科学   581篇
妇产科学   472篇
基础医学   4971篇
口腔科学   962篇
临床医学   3827篇
内科学   6193篇
皮肤病学   533篇
神经病学   1918篇
特种医学   1864篇
外科学   5877篇
综合类   288篇
一般理论   11篇
预防医学   2846篇
眼科学   420篇
药学   1289篇
  1篇
中国医学   11篇
肿瘤学   1126篇
  2021年   349篇
  2020年   261篇
  2018年   336篇
  2017年   366篇
  2016年   537篇
  2015年   866篇
  2014年   1470篇
  2013年   2107篇
  2012年   633篇
  2011年   538篇
  2010年   1162篇
  2009年   1263篇
  2008年   496篇
  2007年   310篇
  2006年   427篇
  2005年   358篇
  2004年   311篇
  2002年   292篇
  2001年   445篇
  2000年   355篇
  1999年   565篇
  1998年   823篇
  1997年   785篇
  1996年   842篇
  1995年   786篇
  1994年   671篇
  1993年   631篇
  1992年   599篇
  1991年   570篇
  1990年   517篇
  1989年   614篇
  1988年   640篇
  1987年   630篇
  1986年   572篇
  1985年   614篇
  1984年   542篇
  1983年   533篇
  1982年   602篇
  1981年   558篇
  1980年   537篇
  1979年   511篇
  1978年   502篇
  1977年   510篇
  1976年   454篇
  1975年   398篇
  1974年   354篇
  1973年   333篇
  1972年   335篇
  1971年   304篇
  1970年   256篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Vitiligo and psoriasis are both common skin disorders. However, psoriasis strictly confined to pre-existing vitiligo areas is rare and suggests a causal relationship. We report here on two patients with a strict anatomical colocalization of vitiligo and psoriasis. The histopathological examinations showed typical changes for both diseases together with a dense infiltrate of CD4+ and CD8+ T cells. By immunohistochemistry, intracytoplasmatic granzyme B and tumour necrosis factor alpha (TNF-alpha) were detected within the T-cell population, suggesting the functional activity of these cells and the creation of a local T helper 1 (Th1)-cytokine milieu. Additionally, in one patient we could identify anti-melanocytic T cells by tetramer staining and enzyme-linked immunospot (ELISPOT) analysis. These skin-infiltrating lymphocytes might trigger, by the local production of Th-1 cytokines such as TNF-alpha and interferon-gamma (IFN-gamma), the eruption of psoriatic plaques in patients with a genetic predisposition for psoriasis.  相似文献   
2.
3.
4.
The severity of illness in transplant patients and the complexity of transplant operations results in significant postoperative morbidity and mortality. Remarkable efforts have been made by transplant physicians to study and improve organ allocation, graft and patient survival, immunosuppression and the long-term management of post-transplant complications. Less effort has been spent studying the actual transplant operation and systems of acute transplant care. The National Surgical Quality Improvement Program (NSQIP) has provided a standardized approach to quality improvement and has demonstrated significant potential for a reduction in postoperative morbidity and mortality in other surgical disciplines. Medical centers are under increasing pressure to measure surgical quality and the nexus of transplant surgical quality improvement should not lie in the hands of CMS or JACHO, but rather it should be created and developed within the transplant community. The time has come for a national transplant surgical quality improvement program based on the NSQIP infrastructure. Such a proactive approach toward quality improvement from the transplant community is an excellent investment for patients, providers and health care payers.  相似文献   
5.
6.
7.
The commodity model of social support and features of Nondirective Support may clarify varied results of support interventions for smoking cessation. A commodity model views social support as attractive in and of itself and as an alternative to high-risk choices such as smoking. If such support is easily accessible, a would-be quitter is less likely to choose to smoke. Consistent with the commodity model, social support interventions tend to be effective as long as support remains available, but they lose their effects when support is terminated. From a second approach, Nondirective Support entails accepting recipients' goals, cooperating without taking control, and validating recipients' feelings. In contrast, Directive Support entails taking control and telling recipients what to do and feel. Review of support interventions indicates the value of the continued availability of support suggested by the commodity model and of Nondirective Support's flexibility and responsiveness to the person.  相似文献   
8.
An educational intervention was developed to improve family practice residents' ability to obtain useful information from pharmaceutical representatives. The curriculum is based on the traditional one-on-one drug detail. The objectives are to develop residents' skills in controlling the interview, promote skills for critically analyzing drug-promotional material, and discuss ethical issues. The contents include an assessment tool, suggested readings, and interview questions with rationale. After 5 years, residents' confidence in all areas of the curriculum improved significantly.  相似文献   
9.
Summary Cytosine arabinsodie (ara-C) and etoposide (VP-16) display synergy in the laboratory. Twenty-six patients participated in a phase I study of high-dose ara-C in combination with VP-16. The dose of VP-16 was held constant at 50 mg/m2 as an intermittent infusion over 33 h; escalating doses of ara-C were given as infusions during hours 9–12 and 21–24. Myelosuppression was the dose-limiting toxicity and occurred with doses considerably less than those expected from studies of the two drugs as single agents. The suggested initial doses for phase II trials with this schedule are 750 mg/m2×2 doses of ara-C and 50 mg/m2 of VP-16. Nonhematologic toxicity was minimal; therefore, further dose escalation is feasible in patients in whom myelosuppression is acceptable.Supported in part by grants from the National Cancer Institute (CA-12197 and CA-09422) and the American Cancer Society CF-85-182  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