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   3250篇
  免费   359篇
  国内免费   20篇
耳鼻咽喉   43篇
儿科学   116篇
妇产科学   93篇
基础医学   423篇
口腔科学   98篇
临床医学   370篇
内科学   876篇
皮肤病学   58篇
神经病学   281篇
特种医学   144篇
外科学   385篇
综合类   99篇
一般理论   1篇
预防医学   237篇
眼科学   33篇
药学   188篇
中国医学   1篇
肿瘤学   183篇
  2022年   15篇
  2021年   33篇
  2020年   38篇
  2019年   48篇
  2018年   55篇
  2017年   47篇
  2016年   51篇
  2015年   49篇
  2014年   70篇
  2013年   112篇
  2012年   153篇
  2011年   159篇
  2010年   144篇
  2009年   128篇
  2008年   132篇
  2007年   178篇
  2006年   177篇
  2005年   148篇
  2004年   153篇
  2003年   119篇
  2002年   93篇
  2001年   90篇
  2000年   105篇
  1999年   107篇
  1998年   78篇
  1997年   61篇
  1996年   56篇
  1995年   57篇
  1994年   52篇
  1993年   48篇
  1992年   89篇
  1991年   63篇
  1990年   62篇
  1989年   57篇
  1988年   58篇
  1987年   67篇
  1986年   44篇
  1985年   46篇
  1984年   47篇
  1983年   30篇
  1982年   25篇
  1981年   23篇
  1980年   20篇
  1979年   23篇
  1978年   28篇
  1977年   24篇
  1976年   16篇
  1975年   18篇
  1973年   15篇
  1971年   17篇
排序方式: 共有3629条查询结果,搜索用时 759 毫秒
1.
2.
BACKGROUND: On December 26, 2004, the biggest earthquake for 40 years, measuring 9.0 on the Richter scale, triggered a tsunami that pounded the coastal areas of South Asia and East Africa. The effects of the tsunami on skin conditions have not been evaluated. OBJECTIVE: To determine the influence of the tsunami on skin conditions by evaluating the skin problems of patients presenting at hospitals after the tsunami. METHODS: Between 5 and 25 January 2005, two dermatologists evaluated patients who complained of skin problems at an outpatient clinic and emergency room of a general hospital in Banda Aceh, Aceh Province, Indonesia. RESULTS: The total number of patients that presented during the study period was 235 (131 males and 104 females), and they had a total of 265 skin problems. In terms of age distribution, most subjects were in their fourth decade (23.0%), followed by the third (22.6%) and fifth decade (16.6%). The most prevalent skin problems were infections-infestations (32.5%), followed by eczemas (29.8%) and traumatic skin disorders (29.4%). In males, traumatic skin disorders were most common. The great majority of infection-infestation cases involved superficial fungal infections. Contact dermatitis accounted for three-quarters of eczema cases, and mainly involved the arms (40.0%) and legs (27.1%). The majority of traumatic skin disorders were lacerations, punctures and penetrations, and the feet (44.7%) and hands (18.8%) were most frequently affected. CONCLUSIONS: Unhygienic conditions, exposure to a hazardous environment and contact with various objects during and after the tsunami probably increased the prevalence of infections-infestations, traumatic skin disorders and contact dermatitis. To prevent these problems and associated secondary bacterial infections, health-related education and early medical management are required.  相似文献   
3.
A Decade of Change in Obesity Surgery   总被引:4,自引:0,他引:4  
Background: The International (formerly National) Bariatric Surgery Registry began collecting data in January 1986. The aim of this study was to examine changes in the practice of surgical treatment of severe obesity that occurred during the decade of 1986 through 1995, as observed in the IBSR data. Methods: All data submitted to the IBSR during the decade were transferred to the IBM mainframe computer for analysis. Characteristics of operative type populations were compared over time using analysis of variance (ANOVA) for age, body mass index (BMI), operative weight and Chi-square (χ2) test for gender. Results: There has been a steady increase over the decade in mean patient weight. The operations used have changed from predominantly ‘simple’ operations to more frequent use of ‘complex’ operations. Within the categories of ‘simple’ and ‘complex’, an increase in the variety of operations occurred. As a group, patients with ‘simple’ operations have been heavier, more often male and public pay patients than those who have undergone ‘complex’ operations. One year weight loss was greater for Roux-en-Y gastric bypass (RGB) than vertical banded gastroplasty (VBG), but follow-up rates were too low to study the relative merits of the operations used. The reported incidence of operative mortality and serious complications (leak with peritonitis, abscess and pulmonary embolism) remained low. Conclusions: These observations and their implications can be summarized in three statements which relate to action for improved patient care in the beginning of the new century: (1) increasing weight of candidates for surgical treatment during this decade indicates the need for earlier use of operative treatment before irreversible complications of obesity can develop; (2) low risk of obesity surgery, decreasing postoperative hospital stay, and early weight control support the continued and increased use of surgical treatment; (3) continued widespread use of both ‘simple’ and ‘complex’ operations with increased modifications of standard RGB and VBG procedures emphasizes the need for standardized long-term data and analyses regarding both weight control and postoperative side-effects.  相似文献   
4.
5.

Background  

The objective of this study was to examine missed opportunities for participation in a prevention of mother-to-child transmission (PMTCT) programme in three sites in South Africa. A rapid anthropological assessment was used to collect in-depth data from 58 HIV-positive women who were enrolled in a larger cohort study to assess mother-to-child HIV transmission. Semi-structured interviews were conducted with the women in order to gain an understanding of their experiences of antenatal care and to identify missed opportunities for participation in PMTCT.  相似文献   
6.
7.
8.
We used a quantitative immunoassay to examine the effects of human serum and immunoglobulins on neurofilament protein expression in cultures of chick spinal neurons. Compared with cultures grown in the presence of serum from healthy controls or patients with other neurologic disorders, ALS serum lowered the level of neurofilament proteins. Effects were similar with or without muscle-derived neurotrophic factors; there was no specificity for motor neurons. No neurotoxic activity was found in immunoglobulin fractions, and there was no evidence of circulating antibodies that might neutralize muscle-derived neurotrophic factors or induce cytolysis of spinal neurons.  相似文献   
9.
One hundred patients with malignant biliary obstruction underwent palliative therapy by means of percutaneous transhepatic placement of 114 biliary endoprostheses. All patients were then followed up for at least 18 months or until death. Retrospective evaluation of the 95 patients who died showed an average survival time of 5.0 months. The five remaining patients have survived an average of 29.8 months. During the 1st week after stent insertion, a second manipulation was performed to improve stent function in nine patients. Overall, 14 (12.3%) of the stents became obstructed and six (5.2%) migrated; 86 patients required no further therapy for biliary obstruction or stent malfunction. The 30-day mortality rate was 12%; none of the deaths were directly attributable to a complication of the stent placement procedure.  相似文献   
10.
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