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   10271篇
  免费   571篇
  国内免费   43篇
耳鼻咽喉   252篇
儿科学   338篇
妇产科学   134篇
基础医学   1545篇
口腔科学   327篇
临床医学   1035篇
内科学   1832篇
皮肤病学   223篇
神经病学   808篇
特种医学   482篇
外科学   1473篇
综合类   99篇
一般理论   9篇
预防医学   608篇
眼科学   396篇
药学   727篇
中国医学   20篇
肿瘤学   577篇
  2022年   56篇
  2021年   124篇
  2020年   82篇
  2019年   131篇
  2018年   160篇
  2017年   145篇
  2016年   170篇
  2015年   191篇
  2014年   223篇
  2013年   334篇
  2012年   400篇
  2011年   470篇
  2010年   274篇
  2009年   243篇
  2008年   431篇
  2007年   471篇
  2006年   466篇
  2005年   443篇
  2004年   441篇
  2003年   413篇
  2002年   326篇
  2001年   423篇
  2000年   378篇
  1999年   333篇
  1998年   163篇
  1997年   123篇
  1996年   129篇
  1995年   96篇
  1994年   105篇
  1993年   58篇
  1992年   175篇
  1991年   166篇
  1990年   180篇
  1989年   177篇
  1988年   144篇
  1987年   132篇
  1986年   119篇
  1985年   121篇
  1984年   88篇
  1983年   84篇
  1982年   56篇
  1981年   55篇
  1980年   58篇
  1979年   86篇
  1978年   72篇
  1977年   79篇
  1975年   57篇
  1974年   58篇
  1973年   56篇
  1972年   81篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
PURPOSE: Much debate has arisen about whether antioxidant supplementation alters the efficacy of cancer chemotherapy. Some have argued that antioxidants scavenge the reactive oxygen species integral to the activity of certain chemotherapy drugs, thereby diminishing treatment efficacy. Others suggest antioxidants may mitigate toxicity and thus allow for uninterrupted treatment schedules and a reduced need for lowering chemotherapy doses. The objective of this study is to systematically review the literature in order to compile results from randomized trials that evaluate concurrent use of antioxidants with chemotherapy. DESIGN: MEDLINE, Cochrane, CinAhl, AMED, AltHealthWatch and EMBASE databases were searched. Only randomized, controlled clinical trials that reported survival and/or tumor response were included in the final tally. The literature searches were performed in duplicate following a standardized protocol. No meta-analysis was performed due to heterogeneity of tumor types and treatment protocols used in trials that met the inclusion criteria. RESULTS: Of 845 articles considered, 19 trials met the inclusion criteria. Antioxidants evaluated were: glutathione (7), melatonin (4), vitamin A (2), an antioxidant mixture (2), vitamin C (1), N-acetylcysteine (1), vitamin E (1) and ellagic acid (1). Subjects of most studies had advanced or relapsed disease. CONCLUSION: None of the trials reported evidence of significant decreases in efficacy from antioxidant supplementation during chemotherapy. Many of the studies indicated that antioxidant supplementation resulted in either increased survival times, increased tumor responses, or both, as well as fewer toxicities than controls; however, lack of adequate statistical power was a consistent limitation. Large, well-designed studies of antioxidant supplementation concurrent with chemotherapy are warranted.  相似文献   
982.
Abstract: Our objective was to compare the efficacy of selenium sulfide shampoo 1% and ciclopirox shampoo 1% as adjunctive treatments for tinea capitis in children. Forty children aged 1–11 years with clinically diagnosed tinea capitis were randomized to receive selenium sulfide shampoo 1% or ciclopirox shampoo 1% twice a week as adjuncts to an 8‐week course of ultramicronized griseofulvin dosed at 10–12 mg/kg/day. At weeks 2, 4, and 8, subjects returned to the clinic for evaluation and scalp cultures. Subjects then returned for follow‐up visits 4 weeks after completing treatment. Overall, by 8 weeks, 30 of 33 (90.9%) treated children demonstrated mycological cure. Selenium sulfide shampoo 1% and ciclopirox shampoo 1% were equally effective as adjunctive treatments for tinea capitis in children in our study.  相似文献   
983.
984.
985.
986.
987.
988.

Background

Extracorporeal photopheresis (ECP) treatment, mostly based on apheresis technology, is used for immunomodulation in various diseases such as cutaneous T-cell lymphoma, graft versus host disease and other (auto)immune disorders. The aim of this study was to collect high cell counts and purity in shorter procedure times using an ECP off-line system with an increased collection flow rate of 2 mL/min to a target volume of 200 mL buffy coat.

Study design and methods

In this prospective study, data of routinely performed off-line photopheresis treatments were collected and analyzed at the Central Institute for Blood Transfusion & Department of Immunology (ZIB) of the Tirol Kliniken, to assess absolute cell counts and procedure times and to calculate collection efficiencies (CE2).

Results

A total of 22 patients participated in this study. The processed blood volume was 4312 mL, the collection time 120 min, overall procedure time 157 min and the absolute cell counts of treated white blood cells (WBC) and mononuclear cells (MNC) were 5.0 and 4.3 × 109 respectively (median values). The calculated CE2 for WBC and MNC was 21.1% and 58.5%, the proportion of treated MNCs of the total number of MNCs present was 55.0%.

Conclusion

The data presented in this study show high therapeutically effective cell counts collected with a high MNC purity within a shorter overall collection/procedure time due to an increased collection flow rate.  相似文献   
989.
Upcoming experimental and epidemiological data have identified the endogenous non-proteinogenic amino acid L-homoarginine (L-hArg) not only as a novel biomarker for cardiovascular disease but also as being directly involved in the pathogenesis of cardiac dysfunction. The association of low L-hArg levels with adverse cardiovascular events and mortality has proposed the idea of nutritional supplementation to rescue pathways inversely associated with cardiovascular health. Subsequent clinical and experimental studies contributed significantly to our knowledge of potential effects on the cardiorenal axis, acting either as a biomarker or a cardiovascular active agent. In this review article, we provide a comprehensive summary of the L-hArg metabolism, pathophysiological aspects, and current developments in the field of experimental and clinical evidence in favor of protective cardiovascular effects. Establishing a reliable biomarker to identify patients at high risk to die of cardiovascular disease represents one of the main goals for tackling this disease and providing individual therapeutic guidance.  相似文献   
990.
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