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   1444818篇
  免费   119459篇
  国内免费   6612篇
耳鼻咽喉   18510篇
儿科学   46336篇
妇产科学   38837篇
基础医学   198488篇
口腔科学   40237篇
临床医学   127427篇
内科学   305139篇
皮肤病学   35378篇
神经病学   119065篇
特种医学   57919篇
外国民族医学   275篇
外科学   223629篇
综合类   32095篇
现状与发展   2篇
一般理论   444篇
预防医学   117242篇
眼科学   30512篇
药学   101245篇
  5篇
中国医学   2732篇
肿瘤学   75372篇
  2019年   11537篇
  2018年   17687篇
  2017年   13152篇
  2016年   15100篇
  2015年   16864篇
  2014年   22865篇
  2013年   34234篇
  2012年   44294篇
  2011年   47410篇
  2010年   28642篇
  2009年   26876篇
  2008年   43211篇
  2007年   46085篇
  2006年   46657篇
  2005年   45205篇
  2004年   42620篇
  2003年   41305篇
  2002年   39019篇
  2001年   69049篇
  2000年   71355篇
  1999年   59183篇
  1998年   17133篇
  1997年   15282篇
  1996年   16258篇
  1995年   16430篇
  1994年   15245篇
  1993年   14286篇
  1992年   48111篇
  1991年   46600篇
  1990年   44719篇
  1989年   42436篇
  1988年   39263篇
  1987年   38593篇
  1986年   36381篇
  1985年   35078篇
  1984年   26687篇
  1983年   22351篇
  1982年   13968篇
  1981年   12560篇
  1980年   11826篇
  1979年   23833篇
  1978年   17238篇
  1977年   14553篇
  1976年   13352篇
  1975年   13958篇
  1974年   16362篇
  1973年   15702篇
  1972年   14432篇
  1971年   13304篇
  1970年   12139篇
排序方式: 共有10000条查询结果,搜索用时 953 毫秒
31.
32.

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   
33.
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   
34.
Chondrocytes are the main cells in the extracellular matrix (ECM) of articular cartilage and possess a highly differentiated phenotype that is the hallmark of the unique physiological functions of this specialised load-bearing connective tissue. The plasma membrane of articular chondrocytes contains a rich and diverse complement of membrane proteins, known as the membranome, which defines the cell surface phenotype of the cells. The membranome is a key target of pharmacological agents and is important for chondrocyte function. It includes channels, transporters, enzymes, receptors, and anchors for intracellular, cytoskeletal and ECM proteins and other macromolecular complexes. The chondrocyte channelome is a sub-compartment of the membranome and includes a complete set of ion channels and porins expressed in these cells. Many of these are multi-functional proteins with “moonlighting” roles, serving as channels, receptors and signalling components of larger molecular assemblies. The aim of this review is to summarise our current knowledge of the fundamental aspects of the chondrocyte channelome, discuss its relevance to cartilage biology and highlight its possible role in the pathogenesis of osteoarthritis (OA). Excessive and inappropriate mechanical loads, an inflammatory micro-environment, alternative splicing of channel components or accumulation of basic calcium phosphate crystals can result in an altered chondrocyte channelome impairing its function. Alterations in Ca2+ signalling may lead to defective synthesis of ECM macromolecules and aggravated catabolic responses in chondrocytes, which is an important and relatively unexplored aspect of the complex and poorly understood mechanism of OA development.  相似文献   
35.
36.
37.
38.
39.
Henna, derived from a combination of natural leaves and coloring additives, is a common decorative dye traditionally used in many Islamic religious celebrations. Para‐phenylenediamine (PPD), a major component of black henna tattoo, is a strong sensitizer and common allergen. We report a case of severe connubial allergic contact dermatitis after black henna heterotransfer in a girl.  相似文献   
40.
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