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   2081篇
  免费   94篇
  国内免费   6篇
耳鼻咽喉   42篇
儿科学   76篇
妇产科学   93篇
基础医学   156篇
口腔科学   137篇
临床医学   187篇
内科学   385篇
皮肤病学   21篇
神经病学   214篇
特种医学   101篇
外科学   501篇
综合类   30篇
一般理论   1篇
预防医学   59篇
眼科学   41篇
药学   80篇
肿瘤学   57篇
  2024年   3篇
  2023年   22篇
  2022年   41篇
  2021年   85篇
  2020年   53篇
  2019年   62篇
  2018年   85篇
  2017年   44篇
  2016年   77篇
  2015年   101篇
  2014年   106篇
  2013年   130篇
  2012年   188篇
  2011年   173篇
  2010年   83篇
  2009年   75篇
  2008年   136篇
  2007年   155篇
  2006年   122篇
  2005年   129篇
  2004年   93篇
  2003年   71篇
  2002年   49篇
  2001年   27篇
  2000年   18篇
  1999年   10篇
  1998年   5篇
  1997年   5篇
  1996年   2篇
  1995年   1篇
  1994年   2篇
  1993年   2篇
  1992年   1篇
  1990年   4篇
  1989年   3篇
  1987年   3篇
  1986年   2篇
  1984年   2篇
  1983年   2篇
  1981年   1篇
  1980年   1篇
  1979年   3篇
  1977年   1篇
  1976年   1篇
  1975年   1篇
  1972年   1篇
排序方式: 共有2181条查询结果,搜索用时 31 毫秒
11.
12.
Influence of a self-etching primer on compound nerve action potentials   总被引:1,自引:0,他引:1  
The aim of this study was to evaluate the effect of self-etching primers on nerve conductance. A self-etching primer (One Up Bond F) which combines etching and bonding in one step, and a fifth-generation bonding agent (Prime&Bond NT ) were tested. Isolated rat sciatic nerves were placed between two platinum electrodes in a bath containing Tyrode solution. The bonding agents were brought into contact with the nerves and the evoked compound action potentials (CAP) were recorded before and after contact with the materials. One Up Bond F caused total inhibition of the CAP within an average time of 7 min. All CAPs in this group were blocked irreversibly. As with Prime&Bond NT, the reduction in CAP was 45.9% after an application time of 15 min, after which readings were terminated. Recovery of the CAP in this group were maintained after rinsing with fresh tyrode solution. One Up Bond F elicited faster blocking of nerve conductance under the conditions of this model. In the context of dentin desensitization with bonding agents, the self-etching primer may be more effective, clinically.  相似文献   
13.
In this study, attachment and growth of Baby Hamster Kidney (BHK) cells on ethylene diamine (EDA)-plasma-treated poly(L-lactide/epsilon-caprolactone) biodegradable copolymer films were investigated. The co-polymer (Mw: 58000; Mn: 35000 and PI 1.60) was synthesised by ring-opening polymerization of the respective dimers with using stannous octoate as the catalyst. The final ratio of L-lactide to epsilon-caprolactone obtained by 1H-NMR was 87:13. The co-polymer films were treated with the EDA-plasma in a glow-discharge apparatus. The BHK-30 cell line was cultured on plain and EDA-plasma-treated films and their pre-wetted forms (with ethanol and/or cell culture medium before use). Cell attachment and growth were followed. Alkaline phosphatase (ALP) activity and glucose uptake in cell culture medium were also investigated. There was no attachment in the first 12 h. Glow-discharge treatment increased significantly the attachment and growth. Pre-wetting with ethanol and cell culture medium was also increase significantly both the attachment and growth.  相似文献   
14.
Homeostasis of memory T cells   总被引:13,自引:0,他引:13  
Summary: The pool of memory T cells is regulated by homeostatic mechanisms to persist for prolonged periods at a relatively steady overall size. Recent work has shown that two members of the common γ chain (γc) family of cytokines, interleukin‐7 (IL‐7) and IL‐15, govern homeostasis of memory T cells. These two cytokines work in conjunction to support memory T‐cell survival and intermittent background proliferation. Normal animals contain significant numbers of spontaneously arising memory‐phenotype (MP) cells, though whether these cells are representative of true antigen‐specific memory T cells is unclear. Nevertheless, it appears that the two types of memory cells do not display identical homeostatic requirements. For antigen‐specific memory CD8+ T cells, IL‐7 is primarily important for survival while IL‐15 is crucial for their background proliferation. For memory CD4+ T cells, IL‐7 has an important role, whereas the influence of IL‐15 is still unclear.  相似文献   
15.
16.
We aimed to evaluate the learning curve of the surgically standardised ‘Omega Sign’ anatomical endoscopic enucleation (AEEP) of the prostate surgery technique for junior surgeons. This study is a retrospective comparison of cases that underwent AEEP by a mentor surgeon and three junior surgeons who have completed their learning curve. A video-based laser enucleation of the prostate assessment tool (LEAT) composed of 8 steps of the technique was used to assess a senior surgeon and junior surgeons’ surgical compatibility and consistency. The surgeon who defined Omega Sign technique was determined as group 1, and cases by three junior surgeons were identified as group 2. The end points were to assess the reproducibility and repeatability and operative post-operative outcomes of the technique. 55 patients’ videos were rated by five experienced endourologists. There was no significant difference in LEAT scores between the groups among all steps. The most symmetry was found in the 1st and 3rd steps. Inter-rater consistency was also high for each step, with no statistically significant difference between the evaluators. The standardised anatomical ‘Omega Sign’ technique is reproducible for the junior surgeons. The operative steps can be performed with high consistency, and the functional and perioperative outcomes are comparable with the senior surgeon.  相似文献   
17.
18.
Mycobacterium tuberculosis (H(37)R(v))-infected guinea-pig model was used to investigate the effect of water extract of propolis (WEP). After subcutaneous inoculation of tubercle bacilli, each animal received oral WEP (n=9), isoniazid (n=5) or saline (n=6) as placebo and were sacrificed 30 days later. Formation of necrosis was less prominent in the group treated with WEP, but was not statistically significant (P>0.05). The granuloma formation in the same group was more prominent than the placebo and isoniazid groups; however, this finding failed to reach statistical significance by the Kruskal-Wallis test (P>0.05). These findings suggest that Turkish WEP may have a limited effect on the development of tuberculosis infection in this guinea-pig model.  相似文献   
19.
20.
The tibial eminence fractures are most frequently observed in children and adolescents increasingly. Their classification and management are mainly made by the displacement of the fracture fragment. The surgical management has evolved from open to arthroscopic techniques. Various fixation techniques have been defined. Mainly, there are 2 types of fixation: screw and suture-based methods. Although recent studies have demonstrated the biomechanical advantages of newer suture-based fixation methods, the best method of fixation has not been defined, yet. Currently, nondisplaced and reducible fractures are managed nonoperatively, and displaced and irreducible fractures are managed operatively. Until the best surgical method is defined by higher level of evidence studies clinically, functionally, radiologically, and biomechanically, the type of fixation will be chosen by considering the experience of the surgeon, the clinical status of the patient, the availability of the implants, and the morphology of these fractures.  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