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   4344188篇
  免费   349523篇
  国内免费   14674篇
耳鼻咽喉   60326篇
儿科学   139408篇
妇产科学   114266篇
基础医学   666694篇
口腔科学   118013篇
临床医学   396684篇
内科学   789757篇
皮肤病学   107730篇
神经病学   368128篇
特种医学   169434篇
外国民族医学   753篇
外科学   656072篇
综合类   121232篇
现状与发展   25篇
一般理论   2617篇
预防医学   358607篇
眼科学   100812篇
药学   307525篇
  25篇
中国医学   11942篇
肿瘤学   218335篇
  2021年   56189篇
  2020年   35825篇
  2019年   58836篇
  2018年   74396篇
  2017年   56669篇
  2016年   62808篇
  2015年   75743篇
  2014年   109993篇
  2013年   175554篇
  2012年   124347篇
  2011年   129089篇
  2010年   125920篇
  2009年   127629篇
  2008年   115236篇
  2007年   122508篇
  2006年   131321篇
  2005年   125405篇
  2004年   126702篇
  2003年   116881篇
  2002年   106121篇
  2001年   166947篇
  2000年   162016篇
  1999年   148672篇
  1998年   71662篇
  1997年   67605篇
  1996年   65624篇
  1995年   61045篇
  1994年   54968篇
  1993年   51013篇
  1992年   106616篇
  1991年   101381篇
  1990年   97237篇
  1989年   94810篇
  1988年   87140篇
  1987年   85302篇
  1986年   80194篇
  1985年   78350篇
  1984年   65393篇
  1983年   58202篇
  1982年   47189篇
  1981年   43860篇
  1980年   41074篇
  1979年   55103篇
  1978年   44753篇
  1977年   39978篇
  1976年   36840篇
  1975年   36804篇
  1974年   39611篇
  1973年   37750篇
  1972年   35359篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
171.
Erosive pustular dermatosis of the scalp (EPDS) is an uncommon chronic inflammatory response to scalp trauma that usually resolves with cicatricial alopecia. It most commonly affects elderly patients with a history of actinic damage. Herein, we describe a 16‐year‐old girl with acrofacial dysostosis type 1 presenting after surgery with crusting purulent scalp lesions, whose clinical presentation and histopathologic findings were consistent with EPDS. A review of the literature on EPDS in children is also detailed.  相似文献   
172.
173.
174.
175.
176.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
177.
178.
179.
180.
Metabolism describes the series of chemical reactions that are concerned with the provision of energy to biological systems. They may be divided into reactions involved in energy yield (catabolism: demand exceeds supply), and energy storage (anabolism: supply exceeds demand). Regulation of these pathways is critical for homeostasis, and derangements in metabolism are seen in a wide variety of pathological processes. Understanding metabolism is key to the treatment of many diseases, notably diabetes, as well as underpinning clinical nutritional support.  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