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   2400489篇
  免费   200242篇
  国内免费   4675篇
耳鼻咽喉   34858篇
儿科学   73227篇
妇产科学   63574篇
基础医学   338998篇
口腔科学   67960篇
临床医学   217873篇
内科学   474869篇
皮肤病学   48970篇
神经病学   202895篇
特种医学   97456篇
外国民族医学   886篇
外科学   364340篇
综合类   56654篇
现状与发展   1篇
一般理论   992篇
预防医学   191813篇
眼科学   56418篇
药学   179998篇
  4篇
中国医学   4705篇
肿瘤学   128915篇
  2018年   25130篇
  2017年   19451篇
  2016年   21482篇
  2015年   24527篇
  2014年   34993篇
  2013年   52486篇
  2012年   71170篇
  2011年   74775篇
  2010年   43986篇
  2009年   42178篇
  2008年   70538篇
  2007年   74789篇
  2006年   75511篇
  2005年   73503篇
  2004年   70544篇
  2003年   68160篇
  2002年   67316篇
  2001年   112925篇
  2000年   116920篇
  1999年   98724篇
  1998年   28068篇
  1997年   25696篇
  1996年   25605篇
  1995年   24741篇
  1994年   23273篇
  1993年   21625篇
  1992年   79569篇
  1991年   76533篇
  1990年   73742篇
  1989年   71000篇
  1988年   65999篇
  1987年   64918篇
  1986年   61440篇
  1985年   58509篇
  1984年   44306篇
  1983年   37728篇
  1982年   22941篇
  1981年   20378篇
  1979年   41375篇
  1978年   29035篇
  1977年   24389篇
  1976年   22858篇
  1975年   24002篇
  1974年   29670篇
  1973年   28075篇
  1972年   26255篇
  1971年   24174篇
  1970年   22778篇
  1969年   21099篇
  1968年   19145篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
41.

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   
42.
43.
44.
45.
46.
47.
Direct peroral cholangioscopy (POC) using an ultra‐slim upper endoscope is one modality of POC for intraductal endoscopic evaluation and treatment of the bile duct. Choledochoduodenostomy (CDS) is one modality of biliary bypass surgery that provides a new route to the bile duct. We carried out direct POC using an ultra‐slim upper endoscope without the use of accessories in 10 patients (four sump syndromes, three bile duct strictures and three intrahepatic duct stones) previously undergoing surgical CDS. Direct POC was successful in all patients. The use of an intraductal balloon catheter was required in one patient for advancement of the endoscope into the bile duct. Distal bile ducts with sump syndromes were cleared using baskets and water irrigation under direct POC. Cholangiocarcinoma was diagnosed in one patient with hilar bile duct stricture after cholangioscopic evaluation and a targeting forceps biopsy under direct POC. Intrahepatic duct stones were successfully extracted after intraductal fragmentation under direct POC. Oozing bleeding occurred during intraductal lithotripsy but stopped spontaneously. Direct POC using an ultra‐slim upper endoscope without the assistance of accessories can easily be carried out in patients undergoing CDS.  相似文献   
48.
49.
Acne vulgaris (acne) is a chronic inflammatory disease of the sebaceous gland, characterized by follicular hyperkeratinization, excessive colonization by Propionibacterium acnes (Pacnes) as well as immune reactions and inflammation. Despite an armamentarium of topical treatments available including benzoyl peroxide, retinoids and azelaic acid, topical antibiotics in monotherapies, especially erythromycin and clindamycin, are still used in Europe to treat acne. This intensive use led to antimicrobial‐resistant P. acnes and staphylococci strains becoming one of the main health issues worldwide. This is an update on the current topical acne treatments available in Europe, their mechanism of action, their potential to induce antimicrobial resistance and their clinical efficacy and safety.  相似文献   
50.
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