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   3491篇
  免费   175篇
  国内免费   32篇
耳鼻咽喉   33篇
儿科学   90篇
妇产科学   48篇
基础医学   313篇
口腔科学   22篇
临床医学   266篇
内科学   633篇
皮肤病学   44篇
神经病学   618篇
特种医学   84篇
外科学   953篇
综合类   12篇
预防医学   154篇
眼科学   25篇
药学   148篇
中国医学   5篇
肿瘤学   250篇
  2023年   30篇
  2022年   51篇
  2021年   85篇
  2020年   56篇
  2019年   98篇
  2018年   92篇
  2017年   73篇
  2016年   80篇
  2015年   112篇
  2014年   147篇
  2013年   155篇
  2012年   241篇
  2011年   276篇
  2010年   169篇
  2009年   125篇
  2008年   209篇
  2007年   220篇
  2006年   191篇
  2005年   172篇
  2004年   160篇
  2003年   149篇
  2002年   130篇
  2001年   68篇
  2000年   67篇
  1999年   58篇
  1998年   31篇
  1997年   22篇
  1996年   30篇
  1995年   21篇
  1994年   20篇
  1993年   22篇
  1992年   46篇
  1991年   37篇
  1990年   46篇
  1989年   34篇
  1988年   25篇
  1987年   24篇
  1986年   15篇
  1985年   15篇
  1984年   13篇
  1983年   13篇
  1982年   7篇
  1981年   4篇
  1980年   5篇
  1979年   9篇
  1978年   6篇
  1977年   5篇
  1976年   5篇
  1975年   5篇
  1966年   6篇
排序方式: 共有3698条查询结果,搜索用时 15 毫秒
71.
72.
73.

Background

Helicobacter pylori infection is still frequent in the community and all infected subjects should be offered an eradication therapy. Nowadays physicians have to face the challenge of antibiotic resistance in treating Helicobacter pylori‐infected individuals.

Aim

This review provides an overview of current international guidelines and reports recent evidence from systematic reviews and clinical trials on the treatment of Helicobacter pylori infection and should help physicians to better treat their patients.

Results

General rules to optimize the management of Helicobacter pylori infection include: (i) considering previous patient's exposure to antibiotics; (ii) using high dose of proton‐pump inhibitors; and (iii) avoiding repeating the same regimen, if it has already failure. Bismuth quadruple therapy and concomitant therapy are the best first‐line empirical treatments in areas with high clarithromycin resistance and in individuals with previous use of macrolides; otherwise, the 14‐day clarithromycin‐containing triple therapy is a valid regimen. The sequential therapy is no longer a suggested treatment by international guidelines.

Conclusions

Current international guidelines are consistent in defining treatment strategies for Helicobacter pylori infection. The use of national registries to monitor the efficacy and tolerability of different regimens in the real world of clinical practice is now needed.  相似文献   
74.
Journal of Thrombosis and Thrombolysis - Homocysteine (Hcy) elevation and vitamin D deficiency have emerged as potential markers of coronary artery disease (CAD). However, even tough...  相似文献   
75.
Heart Failure Reviews - To compare the efficacy and safety of different mechanical circulatory support (MCS) devices in CS. A total of 24 studies (7 randomized controlled...  相似文献   
76.
Cloninger has proposed a tridimensional model as the basis for the classification of personality variants and has developed the Tridimensional Personality Questionnaire (TPQ) as an empirical test of this model. In this study, the TPQ was administered to two groups of young men. One group was comprised of nonalcoholic sons of male alcoholics; the other group consisted of nonalcoholic men with no family history of alcoholism. Since the sons of male alcoholics are considered to be at greater risk to develop alcoholism than the sons of nonalcoholics, it was hypothesized that the two groups would demonstrate differences with regard to one or more personality variants as measured by the TPQ. No statistically significant differences in the three TPQ-subscale scores of the two groups were found.  相似文献   
77.
Expression of carbonic anhydrase 9 at the invasion front of gastric cancers   总被引:5,自引:0,他引:5  
BACKGROUND: Carbonic anhydrase IX (MN/Ca9) catalyses the reversible metabolism of carbon dioxide to carbonic acid and has also been linked to malignant transformation and hypoxia in various cancers. AIMS: To assess the expression and biological role of Ca9 in gastric cancer. METHODS: Using gastric cancer cell lines and tissues, we studied expression of Ca9 by western blot analysis, immunohistochemistry, and polymerase chain reaction. Biological changes after Ca9 transfection and after treatment with 5'-azadeoxycytidine were also analysed in cancer cell lines. RESULTS: Non-cancerous tissues strongly expressed Ca9 with membranous localisation. In contrast, Ca9 expression was frequently lost in gastric cancers (p<0.001). However, gastric cancers that retained Ca9 expression in cancer cells exhibited a shorter postoperative survival (p = 0.028). In vitro analysis revealed that loss of Ca9 expression in gastric cancer cell lines was restored after treatment with 5'-azadeoxycytidine and was associated with increased invasion (p<0.01). Moreover, AGS cells transfected with Ca9 exhibited significantly increased cell proliferation (p<0.05). CONCLUSIONS: A subgroup of gastric cancers retain Ca9 expression in cancer cells at the invasion front. While loss of Ca9 expression is regulated in part by methylation, re-expression of Ca9 is associated with increased invasion, supporting the hypothesis that increased Ca9 expression may contribute to invasion and thus advanced disease and tumour progression in a subset of gastric cancers.  相似文献   
78.
The parietal lobes contribute to body-space representation. The present work aims at characterizing the functional role of the inferior parietal lobe in body-space representation and at studying the different roles of the angular gyrus in the right and left hemisphere. We conducted three separate transcranial direct current stimulation (tDCS) experiments using “tactile distance task” as an implicit measure of body representation. Whereas anodal tDCS on the right angular gyrus influences vocal reaction times (vRT) for stimuli delivered on the ipsilateral body parts without changes of accuracy, right tDCS improved both vRT and accuracy for tactile stimuli on the contralateral limbs. Sham or left parietal anodal tDCS had no effect. These evidences support the view that right parietal areas have a crucial role in the metric component of the body representation.  相似文献   
79.
The nasolacrimal duct in association with the lacrimal puncta, lacrimal canaliculi and lacrimal sac functions to collect and drain the tear film into the nasal cavity at the inferior nasal meatus where a fold of nasal mucosa, the so-called valve of Hasner, prevents mucous from entering the nose. High-resolution computed tomography demonstrated air inside the sac and nasolacrimal duct in approximately 29.3% of healthy patients suggesting that the system is not completely competent and that air and secretions might reach the precorneal film.  相似文献   
80.
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