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   812篇
  免费   59篇
  国内免费   15篇
耳鼻咽喉   6篇
儿科学   47篇
妇产科学   12篇
基础医学   106篇
口腔科学   33篇
临床医学   88篇
内科学   186篇
皮肤病学   35篇
神经病学   18篇
特种医学   131篇
外科学   69篇
综合类   38篇
预防医学   27篇
眼科学   25篇
药学   47篇
中国医学   2篇
肿瘤学   16篇
  2023年   3篇
  2021年   12篇
  2020年   14篇
  2019年   18篇
  2018年   11篇
  2017年   18篇
  2016年   17篇
  2015年   23篇
  2014年   26篇
  2013年   38篇
  2012年   21篇
  2011年   14篇
  2010年   48篇
  2009年   37篇
  2008年   17篇
  2007年   29篇
  2006年   20篇
  2005年   18篇
  2004年   14篇
  2003年   16篇
  2002年   14篇
  2001年   15篇
  2000年   15篇
  1999年   13篇
  1998年   45篇
  1997年   41篇
  1996年   37篇
  1995年   23篇
  1994年   35篇
  1993年   29篇
  1992年   8篇
  1991年   9篇
  1990年   6篇
  1989年   21篇
  1988年   16篇
  1987年   16篇
  1986年   11篇
  1985年   9篇
  1984年   5篇
  1983年   13篇
  1982年   13篇
  1981年   9篇
  1980年   15篇
  1979年   3篇
  1978年   4篇
  1977年   13篇
  1976年   7篇
  1975年   5篇
  1956年   3篇
  1955年   2篇
排序方式: 共有886条查询结果,搜索用时 375 毫秒
1.
2.
Gastroesophageal reflux disease (GERD) is the most common disease of the upper gastrointestinal tract. With the introduction of proton pump inhibitors medical treatment of GERD has been significantly improved. However, the development of laparoscopic antireflux surgery resulted in an increasing interest of surgeons in this disease. An interactive meeting was organized in order to develop an agreement between gastoenterologists and surgeons regarding therapeutic decisions and this is the main topic of this paper.  相似文献   
3.
4.
5.
Human beta-defensin 2 (DEFB4, also known as DEFB2 or hBD-2) is a salt-sensitive antimicrobial protein that is expressed in lung epithelia. Previous work has shown that it is encoded in a cluster of beta-defensin genes at 8p23.1, which varies in copy number between 2 and 12 in different individuals. We determined the copy number of this locus in 355 patients with cystic fibrosis (CF), and tested for correlation between beta-defensin cluster genomic copy number and lung disease associated with CF. No significant association was found.  相似文献   
6.
With thousands of complementary and alternative medicine (CAM) treatments currently being used in the United States today, it is challenging to design a concise body of CAM content which will fit into already overly full curricula for health care students. The purpose of this article is to outline key principles which 15 National Center for Complementary and Alternative Medicine-funded education programs found useful when developing CAM course-work and selecting CAM content. Three key guiding principles are discussed: teach foundational CAM competencies to give students a framework for learning about CAM; choose specific content on the basis of evidence, demographics and condition (what conditions are most appropriate for CAM therapies?); and finally, provide students with skills for future learning, including where to find reliable information about CAM and how to search the scientific literature and assess the results of CAM research. Most of the programs developed evidence-based guides to help students find reliable CAM resources. The cumulative experiences of the 15 programs have been compiled, and an annotated table outlining the most highly recommended resources about CAM is presented.  相似文献   
7.
Thanatophoric dwarfism (TD) is a sporadic lethal skeletal dysplasia with micromelic shortening of the limbs, macrocephaly, platyspondyly and reduced thoracic cavity. In the most common subtype (TD1), femurs are curved, while in TD2, straight femurs are associated with cloverleaf skull. Mutations in the fibroblast growth factor receptor 3 (FGFR3) gene were identified in both subtypes. While TD2 was accounted for by a single recurrent mutation in the tyrosine kinase 2 domain, TD1 resulted from either stop codon mutations or missense mutations in the extracellular domain of the gene. Here, we report the identification of FGFR3 mutations in 25/26 TD cases. Two novel missense mutations (Y373C and G370C) were detected in 8/26 and 1/26 TD1 cases respectively. Both mutations created cysteine residues in the juxta extramembrane domain of the receptor. Sixteen cases carried the previously reported R248C (9/26 cases), S249C (2/26 cases) or stop codon FGFR3 mutations (5/26 cases). Our results suggest that TD1 is a genetically homogeneous condition and give additional support to the view that newly created cysteine residues in the extracellular domain of the protein play a key role in the severity of the disease.   相似文献   
8.
We have recently shown using dansyl-L-lysine exclusion studies that the release of human chorionic gonadotrophin (HCG) in conjunction with L- lactate dehydrogenase (LDH) from first trimester villi during organ culture is symptomatic of syncytiotrophoblast degeneration. The purpose of this study was to examine chorionic villi at the ultrastructural level in order to determine events occurring during organ culture. The tissue was sampled after 0, 24, 48 and 120 h in culture and processed for electron microscopy. In addition to confirming the previously recorded syncytial degeneration, the electron micrographs showed clearly the generation of a new syncytiotrophoblast layer. The new layer, derived from differentiating cytotrophoblast cells, was largely formed by 48 h and was maintained for at least 120 h in culture. This study demonstrates a model which provides an opportunity to study the differentiation of cytotrophoblast cells whilst they retain their anatomical relationships within the villous structure.   相似文献   
9.
10.
Nine novel sugar transporter-like proteins have been discovered in the past 5 years. The mRNA for three of these, the glucose transporters (GLUT) GLUT8, GLUT11 and GLUT12, have been detected in human skeletal muscle. In the present study, we examined the pattern of expression and localization of the GLUT isoforms 8, 11 and 12 in human skeletal muscle using an immunohistochemical approach. Biopsies of human skeletal muscle from sedentary or trained healthy adults, from fetal muscle (24 weeks of gestation), from obese type-2 diabetic subjects, and from patients suffering from polymyositis or amyotrophic lateral sclerosis (ALS) were studied. GLUT8 and 12 immunoreactivity was below detection level in both developing and adult muscle fibres. GLUT11 immunoreactivity, however, was present in slow-twitch muscle fibres, but not in fast twitch fibres. Since, in contrast, GLUT4 was expressed in all investigated muscle fibres, the pattern of expression of GLUT11 differs from that of GLUT4, suggesting a specialized function for GLUT11 with a regulation independent from that of GLUT4. Obesity, type-2 diabetes, training, conditions of de- and reinnervation (ALS) and regeneration (polymyositis) failed to induce GLUT8 or -12 expression. Likewise, the fibre type-dependent pattern of GLUT11 immunoreactivity was unaltered. However, some slow muscle fibres lose their GLUT11 immunoreactivity under regeneration. Our results indicate that GLUT11 immunoreactivity, in contrast to that of GLUT4, is expressed exclusively in slow-twitch muscle fibres and is unaffected by physiological and pathophysiological conditions except in primary myopathy. GLUT8 and GLUT12 do not appear to be of importance in human muscle under physiological and pathophysiological conditions.  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