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   26237篇
  免费   968篇
  国内免费   161篇
耳鼻咽喉   203篇
儿科学   531篇
妇产科学   440篇
基础医学   2825篇
口腔科学   626篇
临床医学   2078篇
内科学   6811篇
皮肤病学   494篇
神经病学   2990篇
特种医学   775篇
外科学   3901篇
综合类   43篇
一般理论   5篇
预防医学   1086篇
眼科学   459篇
药学   1449篇
  3篇
中国医学   30篇
肿瘤学   2617篇
  2024年   91篇
  2023年   198篇
  2022年   398篇
  2021年   772篇
  2020年   473篇
  2019年   637篇
  2018年   693篇
  2017年   550篇
  2016年   620篇
  2015年   690篇
  2014年   1010篇
  2013年   1268篇
  2012年   1995篇
  2011年   1988篇
  2010年   1155篇
  2009年   1067篇
  2008年   1745篇
  2007年   1804篇
  2006年   1666篇
  2005年   1644篇
  2004年   1630篇
  2003年   1352篇
  2002年   1319篇
  2001年   195篇
  2000年   118篇
  1999年   150篇
  1998年   251篇
  1997年   210篇
  1996年   195篇
  1995年   171篇
  1994年   129篇
  1993年   131篇
  1992年   111篇
  1991年   89篇
  1990年   87篇
  1989年   65篇
  1988年   67篇
  1987年   64篇
  1986年   57篇
  1985年   57篇
  1984年   81篇
  1983年   44篇
  1982年   45篇
  1981年   44篇
  1980年   33篇
  1979年   23篇
  1978年   16篇
  1977年   31篇
  1976年   17篇
  1974年   15篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
51.
52.
53.

Introduction

Apical periodontitis (AP) is the expression of a deficient balance between infection and the host immune response.

Methods

If reducing the bacterial load from the root canal and preventing its reinfection may lead to clinical success, then the integrity of the nonspecific immune system has a relevant influence on the outcome of endodontic treatment.

Results

Compromised immune systems and/or genetic alterations of the host's response may as well play an important role on the development, progression, and healing of AP. Thus, immunomodulatory drugs might have the potential to influence both the severity of AP and the outcome of endodontic treatment. Biologic medications are a new class of drugs of monoclonal antibodies or fusion proteins that include fragments of a peculiar cytokine receptor. Specific inflammatory molecules or cells, such as tumor necrosis factor, interleukins, and T or B cells, are the selective targets of these drugs. They modulate the altered immune response and perform an important role in the short-term treatment of chronic inflammatory diseases such as rheumatoid arthritis, refractory Crohn disease, or ulcerative colitis. Despite the clinical positive outcomes and their widespread use, the consequences of administering biologic medications on the development of the dental diseases have not been adequately investigated.

Conclusions

The aim of this review was to give an overview of biologic medications, their composition, their mechanisms of action, and their possible implications on endodontic and other dental diseases.  相似文献   
54.
Loss of sensation in the lip after insertion of an implant is annoying. The aim of this paper was to describe two techniques for management of osseointegrated dental implants that impinge on the mandibular nerve, the purpose of which is to improve sensation without unscrewing the dental implant.  相似文献   
55.
Management of osteonecrosis of the jaw associated with antiresorptive agents is challenging, and outcomes are unpredictable. The severity of disease is the main guide to management, and can help to predict prognosis. Most available staging systems for osteonecrosis, including the widely-used American Association of Oral and Maxillofacial Surgeons (AAOMS) system, classify severity on the basis of clinical and radiographic findings. However, clinical inspection and radiography are limited in their ability to identify the extent of necrotic bone disease compared with computed tomography (CT). We have organised a large multicentre retrospective study (known as MISSION) to investigate the agreement between the AAOMS staging system and the extent of osteonecrosis of the jaw (focal compared with diffuse involvement of bone) as detected on CT. We studied 799 patients with detailed clinical phenotyping who had CT images taken. Features of diffuse bone disease were identified on CT within all AAOMS stages (20%, 8%, 48%, and 24% of patients in stages 0, 1, 2, and 3, respectively). Of the patients classified as stage 0, 110/192 (57%) had diffuse disease on CT, and about 1 in 3 with CT evidence of diffuse bone disease was misclassified by the AAOMS system as having stages 0 and 1 osteonecrosis. In addition, more than a third of patients with AAOMS stage 2 (142/405, 35%) had focal bone disease on CT. We conclude that the AAOMS staging system does not correctly identify the extent of bony disease in patients with osteonecrosis of the jaw.  相似文献   
56.
57.
58.

Background and aims

Reduction of biliary serotonin N-acetyltransferase (AANAT) expression and melatonin administration/secretion in cholangiocytes increases biliary proliferation and the expression of SR, CFTR and Cl/HCO3 AE2. The balance between biliary proliferation/damage is regulated by several autocrine neuroendocrine factors including vascular endothelial growth factor-A/C (VEGF-A/C). VEGFs are secreted by several epithelia, where they modulate cell growth by autocrine and paracrine mechanisms. No data exists regarding the effect of AANAT modulation on the expressions of VEGFs by cholangiocytes.

Methods

In this study, we evaluated the effect of local modulation of biliary AANAT expression on the cholangiocytes synthesis of VEGF-A/C.

Results

The decrease in AANAT expression and subsequent lower melatonin secretion by cholangiocytes was associated with increased expression of VEGF-A/C. Overexpression of AANAT in cholangiocyte lines decreased the expression of VEGF-A/C.

Conclusions

Modulation of melatonin synthesis may affect the expression of VEGF-A/C by cholangiocytes and may modulate the hepatic microvascularization through the regulation of VEGF-A/C expression regulating biliary functions.  相似文献   
59.
Clostridial myonecrosis (CM) is a rare, life threatening necrotizing infection of a skeletal muscle caused by Clostridium perfringens in the majority of cases. The diagnosis may be difficult because of few diagnostic and cutaneous signs early in its course. Standard therapy involves surgical debridements of a devitalized tissue and high‐dose organism‐specific antibiotic therapy. The hyperbaric oxygen has also showed its usefulness in the treatment of these infections. Autograft systems as tissue replacement, based on bioengineered materials, have been demonstrated to be safe and effective treatments for chronic wounds and a suitable physiotherapy is recommended for the recovery of functional impairments of upper extremities. We present a rare case of CM of right upper limb treated with a combination of standard treatments and new techniques.  相似文献   
60.
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