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   4405774篇
  免费   353981篇
  国内免费   14777篇
耳鼻咽喉   61079篇
儿科学   141055篇
妇产科学   115492篇
基础医学   674780篇
口腔科学   119404篇
临床医学   404144篇
内科学   800110篇
皮肤病学   108525篇
神经病学   373339篇
特种医学   171759篇
外国民族医学   763篇
外科学   664860篇
综合类   122543篇
现状与发展   24篇
一般理论   2694篇
预防医学   364754篇
眼科学   102376篇
药学   312439篇
  23篇
中国医学   12013篇
肿瘤学   222356篇
  2021年   56708篇
  2020年   36189篇
  2019年   59290篇
  2018年   75206篇
  2017年   57273篇
  2016年   63399篇
  2015年   76343篇
  2014年   110745篇
  2013年   176569篇
  2012年   128687篇
  2011年   133919篇
  2010年   127393篇
  2009年   128779篇
  2008年   119499篇
  2007年   127383篇
  2006年   135746篇
  2005年   129981篇
  2004年   130836篇
  2003年   120905篇
  2002年   109859篇
  2001年   168222篇
  2000年   163342篇
  1999年   149798篇
  1998年   72131篇
  1997年   67923篇
  1996年   65943篇
  1995年   61314篇
  1994年   55230篇
  1993年   51262篇
  1992年   107589篇
  1991年   102321篇
  1990年   98175篇
  1989年   95692篇
  1988年   88002篇
  1987年   86230篇
  1986年   81024篇
  1985年   79211篇
  1984年   66076篇
  1983年   58796篇
  1982年   47495篇
  1981年   44118篇
  1980年   41308篇
  1979年   55707篇
  1978年   45190篇
  1977年   40371篇
  1976年   37212篇
  1975年   37197篇
  1974年   40097篇
  1973年   38189篇
  1972年   35814篇
排序方式: 共有10000条查询结果,搜索用时 62 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