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   9451篇
  免费   253篇
  国内免费   25篇
耳鼻咽喉   274篇
儿科学   299篇
妇产科学   404篇
基础医学   575篇
口腔科学   223篇
临床医学   670篇
内科学   2080篇
皮肤病学   327篇
神经病学   545篇
特种医学   605篇
外科学   2351篇
综合类   43篇
一般理论   1篇
预防医学   436篇
眼科学   288篇
药学   218篇
中国医学   7篇
肿瘤学   383篇
  2023年   29篇
  2022年   48篇
  2021年   74篇
  2020年   46篇
  2019年   44篇
  2018年   89篇
  2017年   86篇
  2016年   84篇
  2015年   573篇
  2014年   663篇
  2013年   675篇
  2012年   750篇
  2011年   696篇
  2010年   675篇
  2009年   652篇
  2008年   700篇
  2007年   652篇
  2006年   611篇
  2005年   511篇
  2004年   380篇
  2003年   167篇
  2002年   135篇
  2001年   97篇
  2000年   80篇
  1999年   105篇
  1998年   47篇
  1997年   71篇
  1996年   61篇
  1995年   36篇
  1994年   40篇
  1993年   36篇
  1992年   61篇
  1991年   67篇
  1990年   61篇
  1989年   61篇
  1988年   40篇
  1987年   47篇
  1986年   42篇
  1985年   38篇
  1984年   33篇
  1983年   38篇
  1982年   34篇
  1981年   33篇
  1980年   28篇
  1979年   42篇
  1978年   15篇
  1977年   14篇
  1976年   25篇
  1975年   21篇
  1971年   14篇
排序方式: 共有9729条查询结果,搜索用时 15 毫秒
131.
On June 27 2000, the German Self-Administration and lately the German Ministry of Health set the general conditions for a new reimbursement system for the inpatient hospital sector which is based nearly exclusively on lump-sum payments. The Association of Acute Rheumatology Hospitals (VRA) and the DRG-Research-Group, Münster University Hospital, conducted a multi-center trial which included 7266 cases from 22 different hospitals. The data were used to analyze how well the not yet German healthcare adjusted G-DRG system (version 1.0) accounts for rheumatologic diagnostics and treatment as well as problems of specialized hospitals. 7 Adjacent-DRGs covered 91% of all cases, 68% of all cases were grouped into only two different Adjacent-DRGs (169 Bone Diseases and Specific Arthropathies and 166 Other Connective Tissue Disorders). Groups with different complexity which are not appropriately covered by the existing G-DRG system could be identified. The data further revealed a systematically longer length of stay in rheumatology clinics opposed to the average length of stay in the data used for calculating the G-DRGs, due to different structures and procedures of the complex rheumatologic treatment. The results strongly supported the assumption that an accurate reimbursement of rheumatologic cases in the current G-DRG system 1.0 would not have been possible. Adaptations made in the new G-DRG Version 2004 can only partly solve these problems, despite an improved construction of the DRGs. In order to guarantee an appropriate reimbursement of rheumatology clinics from 2005 on, the G-DRG system must be adapted to specific rheumatological pathways and/or alternative or additional reimbursement systems have to be found.  相似文献   
132.
The aim of this work was to investigate the first step in the vectorial translocation of bile acids from the fetus to the mother, which is the transfer across the basal (i.e., fetal-facing) plasma membrane of the trophoblast. Thus, the uptake of [14C]taurocholate by basal plasma membrane vesicles obtained from normal human term placentas was studied. Taurocholate retention into vesicles was studied using a rapid filtration technique that was modified to reduce the taurocholate binding to the filters and to the external surface of the vesicles. Using 100 mumol/L substrate, the membrane vesicles showed a temperature-dependent, Na(+)-independent transport of taurocholate into an osmotically reactive intravesicular space. The initial rate of taurocholate influx in the presence of 100 mmol/L KNO3 followed saturation kinetics (apparent Km for taurocholate = 670 +/- 128 mumol/L; Vmax = 1.86 +/- 0.28 nmol/mg protein.60 s at 37 degrees C). Over the 6.9-7.9 pH range neither internal nor external pH nor inward nor outward proton gradients affected the uptake of taurocholate. When the electrical potential difference across the basal membrane was manipulated by external anion replacement (Cl-, SCN-, SO4(2-), or NO3-) or by valinomycin-induced K(+)-diffusion potential (vesicle inside negative), taurocholate uptake was not significantly modified. Taurocholate uptake was cis-inhibited in the presence of 1 mmol/L glycocholate, 0.5 mmol/L 4,4'-diisothiocyanostilbene-2,2'-disulfonate and 0.5 mmol/L sulfobromophthalein. However, 1 mmol/L probenecid or 0.5 mmol/L p-aminohippurate had no effect. Moreover, preloading the vesicles with 100 mmol/L HCO3- (but not with 100 mmol/L Cl- or 50 mmol/L SO4(2-) induced a significant enhancement in the initial rate of taurocholate uptake. In summary, these findings provide strong evidence for the presence of an electroneutral transport system for taurocholate in the basal plasma membrane of human chorionic trophoblast. They also suggest that this is likely to be an anion-exchange system.  相似文献   
133.
In the past multiple mechanisms could be identified that are involved in anticancer drug resistance; however, diagnostic assays for prediction of therapy response to classical cytostatic drugs did not enter routine clinical diagnostics. Only when new targeted drugs, e.g. tyrosine kinase inhibitors or therapeutic antibodies, were introduced in oncology were diagnostics for prediction of therapy response routinely preformed. First and foremost this was the result of the development of highly standardized techniques, i.e. exact mutation analysis in functional relevant codons of genes encoding signal proteins of cancer-related signal transduction pathways targeted by the new drugs. Due to increasing costs of health systems, in the future predictive diagnostics will probably become more and more important. Therefore, it will be necessary to develop improved diagnostic assays for prediction of individual therapy response.  相似文献   
134.
Treatment guidelines state that cognitive–behavioral therapy (CBT) and interpersonal therapy are the best-supported psychotherapies for bulimia nervosa (BN) and that CBT is the preferred psychological treatment for binge eating disorder (BED). However, no meta-analysis which both examined direct comparisons between psychological treatments for BN and BED and considered the role of moderating variables, such as the degree to which psychotherapy was bona fide, has previously been conducted Thus, such an analysis was undertaken. We included 77 comparisons reported in 53 studies. The results indicated that: (a) bona fide therapies outperformed non-bona fide treatments, (b) bona fide CBT outperformed bona fide non-CBT interventions by a statistically significant margin (only approaching statistical significance for BN and BED when examined individually), but many of these trials had confounds which limited their internal validity, (c) full CBT treatments offered no benefit over their components, and (d) the distribution of effect size differences between bona fide CBT treatments was homogeneously distributed around zero. These findings provide little support for treatment specificity in psychotherapy for BN and BED.  相似文献   
135.
136.
137.
138.
139.
140.
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