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   2137篇
  免费   113篇
  国内免费   76篇
耳鼻咽喉   4篇
儿科学   172篇
妇产科学   31篇
基础医学   227篇
口腔科学   103篇
临床医学   271篇
内科学   499篇
皮肤病学   73篇
神经病学   60篇
特种医学   395篇
外国民族医学   1篇
外科学   117篇
综合类   44篇
预防医学   101篇
眼科学   20篇
药学   96篇
  2篇
肿瘤学   110篇
  2023年   6篇
  2022年   10篇
  2021年   14篇
  2020年   15篇
  2019年   17篇
  2018年   32篇
  2017年   24篇
  2016年   23篇
  2015年   39篇
  2014年   47篇
  2013年   61篇
  2012年   35篇
  2011年   41篇
  2010年   90篇
  2009年   88篇
  2008年   57篇
  2007年   95篇
  2006年   58篇
  2005年   59篇
  2004年   28篇
  2003年   22篇
  2002年   31篇
  2001年   39篇
  2000年   33篇
  1999年   30篇
  1998年   129篇
  1997年   156篇
  1996年   132篇
  1995年   108篇
  1994年   115篇
  1993年   97篇
  1992年   30篇
  1991年   37篇
  1990年   38篇
  1989年   55篇
  1988年   49篇
  1987年   52篇
  1986年   57篇
  1985年   45篇
  1984年   29篇
  1983年   19篇
  1982年   27篇
  1981年   32篇
  1980年   26篇
  1979年   8篇
  1978年   11篇
  1977年   19篇
  1976年   27篇
  1975年   15篇
  1968年   5篇
排序方式: 共有2326条查询结果,搜索用时 0 毫秒
1.
Cutaneous plasmacytosis is a rare disorder characterized by a benign proliferation of mature plasma cells that appears as multiple dark-brown to purplish skin lesions, often associated with polyclonal hypergammaglobulinaemia. We present the case of a 55-year-old Caucasian man who suffered from a cutaneous plasmacytosis associated with two different carcinomas. Cutaneous plasmacytosis seems to be a reactive process because most cases reported are not associated with any apparent underlying disease. Nevertheless, because few reported cases were associated with malignancies, screening of additional neoplasms would be justified.  相似文献   
2.
Techniques of ankle arthroscopy   总被引:1,自引:0,他引:1  
Although arthroscopic instrumentation varies widely, the technique for use is quite similar. Surgeon preferences vary but most arthroscopists agree that it is technique that makes the procedure. Discussed in this presentation is the author's method for preparing the patient for arthroscopic surgery, as well as techniques for using the arthroscope, hand instruments, and power instrumentation.  相似文献   
3.
The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
4.
5.
6.
7.
8.
9.
The purpose of this study is to identify correlates of dental student stress. Associations between characteristics of dental students and their stress levels are examined, along with the association of stress with drug use and health problems. A total of 300 out of 315 dental students completed a questionnaire that measured the frequency and stressfulness of 31 stressors; drug use; health problems; and student characteristics including Type A behavior, career commitment, demographics, and lifestyle variables. Characteristics that were associated with a higher stress level were a higher level of Type A behavior and lower level of career commitment. Greater stress was also associated with a greater frequency of health problems. The results suggest an interactional stress model in which the personalities and attitudes of students are important mediators of the stress response.  相似文献   
10.
FM sonography - a signal-processing technique that uses frequency and phase information as well as amplitude data - shows promise in evaluation of patients with diffuse liver disease. In a prospective blinded review of 37 patients with biopsy-proved liver disease and 42 healthy volunteers, FM sonography was clearly superior to traditional amplitude-based (AM) sonography in distinguishing healthy from diseased subjects. Statistically significant differences were seen in accuracy (FM, 98.7%; AM, 84.8%), sensitivity (FM, 97.3%; AM, 70.3%), and negative predictive value (FM, 97.7%; AM, 78.8%). Our data also suggest that current FM sonographic techniques cannot differentiate among histologic findings associated with different hepatic parenchymal abnormalities. It is unclear, therefore, whether FM imaging can reduce the numbers of patients who require biopsy for diagnosis or the frequency of biopsy procedures in patients with known disease.  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