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   3835篇
  免费   196篇
  国内免费   60篇
耳鼻咽喉   71篇
儿科学   158篇
妇产科学   152篇
基础医学   312篇
口腔科学   109篇
临床医学   323篇
内科学   1240篇
皮肤病学   32篇
神经病学   237篇
特种医学   135篇
外科学   528篇
综合类   94篇
一般理论   1篇
预防医学   163篇
眼科学   167篇
药学   220篇
中国医学   18篇
肿瘤学   131篇
  2024年   5篇
  2023年   30篇
  2022年   61篇
  2021年   117篇
  2020年   54篇
  2019年   80篇
  2018年   95篇
  2017年   77篇
  2016年   85篇
  2015年   135篇
  2014年   155篇
  2013年   202篇
  2012年   304篇
  2011年   304篇
  2010年   177篇
  2009年   159篇
  2008年   281篇
  2007年   320篇
  2006年   270篇
  2005年   265篇
  2004年   189篇
  2003年   176篇
  2002年   139篇
  2001年   52篇
  2000年   48篇
  1999年   43篇
  1998年   27篇
  1997年   34篇
  1996年   21篇
  1995年   21篇
  1994年   13篇
  1993年   12篇
  1992年   14篇
  1991年   18篇
  1990年   13篇
  1989年   13篇
  1988年   17篇
  1987年   11篇
  1986年   5篇
  1985年   11篇
  1984年   6篇
  1983年   6篇
  1982年   2篇
  1981年   3篇
  1980年   4篇
  1979年   5篇
  1973年   2篇
  1932年   1篇
  1931年   1篇
  1929年   1篇
排序方式: 共有4091条查询结果,搜索用时 0 毫秒
101.
102.
Mutation, deactivation and disregulated expression of oncogenes and tumour-suppressor genes may be involved in the pathogenesis of oral squamous cell carcinoma (SCC). Deactivation of the p53 tumour-suppressor gene allows cell proliferation and blocks apoptosis of malignant oral keratinocytes. Mutation in the ras oncog-ene results in persistent mitogenic signalling. Upregul-ated c-Myc expression, in the presence of growth factors, provides an additional proliferative signal. Loss of retino-blastoma tumour-suppressor gene (Rb) function may contribute to oral keratinocyte hyperproliferation and recent evidence suggests that simultaneous deactivation of both p53 and Rb is required for tumourigenesis. Enhanced Bcl-2 and reduced Fas expression inhibit tumour cell apoptosis and may convey resistance to cyto-toxic drugs and T cell-mediated cytotoxicity, respectively. Exogenous mutagens such as tobacco, alcohol and viral oncogenes may cause altered expression of oncogenes and tumour-suppressor genes in some cases of oral SCC. The impact of these mechanisms on future therapies for oral SCC is highlighted.  相似文献   
103.

Purpose

In temporomandibular disorders (TMDs), unless splints are effective, combined therapies are performed. The aim of this study is to show the effectiveness of the local anaesthethic injections (trigger point injections) to the masticatory muscles.

Materials and methods

The study was composed of TMD patients and the predictor variables were therapy combinations including stabilization splint (SS) therapy, SS+trigger point injection therapy (TPI) and arthrocentesis. The primary outcome variables were pain and jaw movements. The follow-ups were done at 1st and 3rd months. 56 patients who were treated for TMD with only SS or combined therapies were included in the study. The effects of additional TPIs were compared to SS therapy alone. Also the effect of arthrocentesis was evaluated too.

Results

All groups revealed significant decreases in pain scores. Decreases in mouth openings were observed in some of the patients in the injection groups.

Conclusion

The combined treatment method in which the injections were applied at shorter time intervals, was a more effective method for decreasing VAS scores in TMD patients in this study but further studies are required.  相似文献   
104.
105.
106.
107.
Concurrent infections with two parasites: a nematode,Trichinella spiralis, and a protozoon,Toxoplasma gondii, were investigated. Antibody production (total immunoglobulin and IgM) was similar in double and single infections. However, the number ofToxoplasma cysts in the brains of mice infected withTrichinella and challenged 1–6 weeks later withToxoplasma was higher than in mice infected withToxoplasma alone, while mice infected withToxoplasma and challenged 4–14 days later withTrichinella had lower worm burdens in the intestine than animals infected withTrichinella alone. Greater loss in body weight was observed in mice infected with both parasites than in those infected with either parasite alone.  相似文献   
108.
The concurrence of acute coronary syndrome with amoxicillin/clavulanic acid intake has been defined as Kounis syndrome. There are some controversial factors which may effect this circumstance. Particularly, the condition which triggers the coronary vasospasm may mimic this syndrome. Furthermore, in the present case, an allergic study had been performed, showing hypersensitivity to penicillin and beta-lactamic agents that ruled out the role of amoxicillin administration.  相似文献   
109.
Aortocaval fistula (ACF) and false aneurysm are a recognized complication of open abdominal aortic aneurysm (AAA) repair. Untreated they are often fatal. However, open surgical repair of this complication is associated with a high operative mortality and a significant complication rate. Endovascular management using a stent-graft to exclude the false aneurysm and fistula is a technically feasible alternative and confers many advantages over open repair by virtue of its minimally invasive nature. We report the endovascular management of this rare but serious complication of open AAA repair.  相似文献   
110.

Background

Patients with lower extremity peripheral artery disease (PAD) are at increased risk of major adverse cardiovascular events (MACE) and major adverse limb events (MALE). There is limited information on the prognosis of patients who experience MALE.

Objectives

Among participants with lower extremity PAD, this study investigated: 1) if hospitalizations, MACE, amputations, and deaths are higher after the first episode of MALE compared with patients with PAD who do not experience MALE; and 2) the impact of treatment with low-dose rivaroxaban and aspirin compared with aspirin alone on the incidence of MALE, peripheral vascular interventions, and all peripheral vascular outcomes over a median follow-up of 21 months.

Methods

We analyzed outcomes in 6,391 patients with lower extremity PAD who were enrolled in the COMPASS (Cardiovascular Outcomes for People Using Anticoagulation Strategies) trial. COMPASS was a randomized, double-blind placebo-controlled study of low-dose rivaroxaban and aspirin combination or rivaroxaban alone compared with aspirin alone. MALE was defined as severe limb ischemia leading to an intervention or major vascular amputation.

Results

A total of 128 patients experienced an incident of MALE. After MALE, the 1-year cumulative risk of a subsequent hospitalization was 61.5%; for vascular amputations, it was 20.5%; for death, it was 8.3%; and for MACE, it was 3.7%. The MALE index event significantly increased the risk of experiencing subsequent hospitalizations (hazard ratio [HR]: 7.21; p < 0.0001), subsequent amputations (HR: 197.5; p < 0.0001), and death (HR: 3.23; p < 0.001). Compared with aspirin alone, the combination of rivaroxaban 2.5 mg twice daily and aspirin lowered the incidence of MALE by 43% (p = 0.01), total vascular amputations by 58% (p = 0.01), peripheral vascular interventions by 24% (p = 0.03), and all peripheral vascular outcomes by 24% (p = 0.02).

Conclusions

Among individuals with lower extremity PAD, the development of MALE is associated with a poor prognosis, making prevention of this condition of utmost importance. The combination of rivaroxaban 2.5 mg twice daily and aspirin significantly lowered the incidence of MALE and the related complications, and this combination should be considered as an important therapy for patients with PAD. (Cardiovascular Outcomes for People Using Anticoagulation Strategies [COMPASS]; NCT01776424)  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