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   3638篇
  免费   196篇
  国内免费   24篇
耳鼻咽喉   60篇
儿科学   139篇
妇产科学   148篇
基础医学   336篇
口腔科学   113篇
临床医学   385篇
内科学   871篇
皮肤病学   70篇
神经病学   290篇
特种医学   103篇
外科学   559篇
综合类   29篇
一般理论   3篇
预防医学   326篇
眼科学   85篇
药学   179篇
中国医学   3篇
肿瘤学   159篇
  2023年   32篇
  2022年   68篇
  2021年   99篇
  2020年   52篇
  2019年   89篇
  2018年   89篇
  2017年   69篇
  2016年   120篇
  2015年   134篇
  2014年   143篇
  2013年   193篇
  2012年   284篇
  2011年   278篇
  2010年   157篇
  2009年   154篇
  2008年   266篇
  2007年   274篇
  2006年   249篇
  2005年   240篇
  2004年   238篇
  2003年   161篇
  2002年   170篇
  2001年   58篇
  2000年   43篇
  1999年   31篇
  1998年   15篇
  1997年   12篇
  1996年   5篇
  1995年   5篇
  1994年   7篇
  1993年   4篇
  1992年   10篇
  1991年   15篇
  1990年   9篇
  1989年   7篇
  1988年   6篇
  1987年   9篇
  1986年   8篇
  1985年   5篇
  1983年   7篇
  1979年   4篇
  1978年   2篇
  1977年   2篇
  1975年   4篇
  1974年   4篇
  1973年   2篇
  1972年   2篇
  1971年   11篇
  1969年   5篇
  1968年   2篇
排序方式: 共有3858条查询结果,搜索用时 15 毫秒
81.
A 19-y-old woman presented with Proteus vulgaris meningitis as a complication of chronic otitis media. Despite treatment with ceftazidime and amikacin no clinical improvement was observed. Cranial MRI revealed right-sided mastoiditis/otitis media and venous sinus thrombosis. After mastoidectomy, repeat cranial MRI demonstrated abscess formation in the venous sinuses. The abscess was drained. Clostridium spp. was isolated from the abscess culture.  相似文献   
82.
83.
Maden O  Atak R  Yetgin E  Senen K  Aras D  Kütük E 《Angiology》2002,53(4):487-491
Cardiac involvement in hydatidosis is rare but because of potentially lethal complications, its recognition is of great importance. The authors present a 55-year-old woman admitted to the clinic with cardiac tamponade and moderate mitral regurgitation caused by a hydatid cyst located at the inferoposterior wall of the left ventricle.  相似文献   
84.

Introduction

Serum leptin levels have been examined in various cancers, with conflicting results. However, there is limited information regarding serum leptin levels and insulin resistance in gastric cancer patients. Therefore, we aimed to investigate serum leptin levels, performance status, insulin levels and insulin resistance in patients with gastric cancer. In addition, we examined the relationship between these measurements and leptin levels.

Material and methods

Thirty-nine patients with gastric cancer and 30 control subjects were enrolled in the study. Serum leptin, total protein, albumin, growth hormone, insulin and glucose levels were measured. The homeostasis model assessment (HOMA) was used to assess insulin resistance.

Results

Serum levels of insulin, glucose and growth hormone and insulin resistance were significantly lower in gastric cancer patients than controls (p < 0.05 for all). In the Pearson correlation analysis, insulin resistance was found to be significantly correlated with serum leptin levels in gastric cancer patients (r = 0.320, p = 0.047). We observed a significant negative correlation between performance status and insulin resistance in patients with cachexia (r = –0.512, p = 0.030), while no association was found in non-cachectic patients.

Conclusions

We concluded that serum leptin levels are significantly lower in gastric cancer patients. In addition, gastric cancer patients have decreases in insulin levels, insulin resistance and growth hormone levels. This study found a positive association between serum leptin levels and insulin resistance. Moreover, there is a negative association between serum leptin levels and growth hormone levels. Thus, low insulin and growth hormone levels may suppress the production of leptin in gastric cancer patients.  相似文献   
85.

Background/Aims:

There are a limited number of studies including the impact of antiplatelet drugs use on hospital outcomes for nonvariceal upper gastrointestinal bleeding. The aim of this study was to determine the effect of anti-aggregant, anti-coagulant and non-steroidal anti-inflammatory drugs upon hospital outcomes in patients with peptic ulcer bleeding.

Materials and Methods:

The patients under treatment with antiaggregant, anticoagulant or non-steroidal anti-inflammatory drugs were categorized as exposed group (n = 118) and the patients who were not taking any of these drugs were categorized as non-exposed group (n = 81). We analyzed the data of drug intake, comorbid disease, blood transfusion, duration of hospital stay, Blatchford/total Rockall score and diagnosis of patients.

Results:

In total, 199 patients were included. Of these 59.3% (exposed group) were taking drugs. The patients in exposed group were significantly older than those in non-exposed group (62.9 ± 17.3 years; 55.5 ± 19.3 years, P = 0.005, respectively). Mean number of red blood cell units transfused (2.21 ± 1.51; 2.05 ± 1.87, P = 0.5), duration of hospital stay (3.46 ± 2.80 days; 3.20 ± 2.30 days, P = 0.532) and gastric ulcer rate (33% vs 23.4%, P = 0.172) were higher in exposed group than in non-exposed group but the differences were not statistically significant. Total Rockall and Blatchford scores of the patients were significantly higher in exposed group than in non-exposed group (3.46 ± 1.72 vs 2.94 ± 1.87, P = 0.045; 10.29 ± 3.15 vs 9.31 ± 3.40, P = 0.038).

Conclusıon:

Our study has shown that anticoagulants, antiaggregants and nonsteroidal anti-inflammatory drugs do not effect duration of hospital stay, red blood cell transfusion requirement and rebleeding for peptic ulcer bleeding.  相似文献   
86.
87.
88.

Objective

We aimed to examine left–right asymmetry in involved and total neck lymph nodes distribution in patients with bilateral laryngeal cancer in the present study.

Methods

Forty-six patients with bilateral laryngeal cancer was included the study. The oncologic database of our otorhinolaryngology department was used. The right and left lymph node with and without involvement by cancer cells counts were retrieved from pathological reports.

Results

The numbers of both involved and total neck lymph nodes were significantly higher on right side than on left side for all neck levels in laryngeal malignancies.

Conclusions

The results of the present study suggest the existence of a left–right asymmetry in neck lymph node distribution and in the neck lymph node distribution involved by laryngeal cancer cells. The stronger cell-mediated immune activity in the left side of humans may be associated with the blocking of the metastatic invasion of cancer cells from laryngeal malignancies in the left body side.  相似文献   
89.
90.
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