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   22394篇
  免费   1844篇
  国内免费   46篇
耳鼻咽喉   503篇
儿科学   606篇
妇产科学   386篇
基础医学   2818篇
口腔科学   326篇
临床医学   2796篇
内科学   4160篇
皮肤病学   419篇
神经病学   1990篇
特种医学   983篇
外科学   3535篇
综合类   427篇
一般理论   20篇
预防医学   1993篇
眼科学   427篇
药学   1433篇
中国医学   14篇
肿瘤学   1448篇
  2023年   226篇
  2022年   300篇
  2021年   921篇
  2020年   535篇
  2019年   834篇
  2018年   962篇
  2017年   599篇
  2016年   607篇
  2015年   679篇
  2014年   932篇
  2013年   1435篇
  2012年   1686篇
  2011年   1591篇
  2010年   854篇
  2009年   704篇
  2008年   1109篇
  2007年   1131篇
  2006年   995篇
  2005年   856篇
  2004年   856篇
  2003年   653篇
  2002年   611篇
  2001年   368篇
  2000年   414篇
  1999年   336篇
  1998年   156篇
  1997年   128篇
  1996年   117篇
  1995年   98篇
  1994年   92篇
  1993年   98篇
  1992年   258篇
  1991年   214篇
  1990年   218篇
  1989年   229篇
  1988年   222篇
  1987年   194篇
  1986年   254篇
  1985年   172篇
  1984年   154篇
  1983年   127篇
  1982年   91篇
  1981年   87篇
  1980年   90篇
  1979年   159篇
  1978年   96篇
  1976年   75篇
  1975年   79篇
  1971年   76篇
  1970年   70篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
The history and clinical findings are presented of a patient who suffered from the uveal effusion syndrome over a 10-year period from 1956. The funduscopic appearance is illustrated both at the time of initial presentation and 36 years later. This condition typically affects healthy middle-aged men and causes recurrent, spontaneous, serous retinal and ciliochoroidal detachments, often resulting in significant visual impairment. Two separate hypotheses have been postulated to explain the pathogenesis of the uveal effusion syndrome, one relating to abnormally thickened sclera, the other to chronic bulbar hypotony. Both are discussed, as is the rationale behind the current management of this unusual condition.  相似文献   
32.
33.
34.
OBJECTIVE: Inpatients with major depressive illness often have coexistent nonaffective psychiatric and/or medical conditions. The authors' objective is to address the following questions: 1) What is the effect of comorbid illness on the severity of major depression and associated psychosocial factors? 2) How does the course of depression differ for patients with and without concurrent illness? 3) Do patients with compound depression differ in rate of recovery and time to recovery from patients with pure depression? METHOD: The subjects were 78 patients with a DSM-III diagnosis of major depression who were consecutively admitted to an acute care university-affiliated psychiatric hospital; 37 of these patients had major depression only and 41 had major depression compounded by a coexisting axis I, II, or III condition. The patients were studied while hospitalized and for 12 months after hospital discharge. Instruments used included the Modified Hamilton Rating Scale for Depression, the Global Assessment Scale, and the Social Readjustment Rating Scale. RESULTS: Patients with compound depression reported significantly poorer functioning over the 12-month follow-up period and had lower recovery rates than the patients with pure depression. There were no differences in recovery rates between men and women with compound depression, but significantly more men than women with pure depression recovered. CONCLUSIONS: Compound depression is a common clinical occurrence, the course of illness is more difficult for patients with compound depression than for patients with pure depression, and the recovery rate of patients with compound depression is lower than that of patients with pure depression.  相似文献   
35.
Intracranial injuries resulting from boxing: a review (1918-1985)   总被引:2,自引:0,他引:2  
A review of the available records indicates that there have been a substantial number of fatalities in boxers due to intracranial injuries sustained in the ring in comparison to the numbers engaged at both amateur and professional levels. The number of such fatalities has decreased steadily in recent years owing to different measures taken by boxing authorities to decrease the physical hazards in the ring and to improve monitoring of boxers during bouts by referees and physicians. The considerable concern about the long-term effects of repeated brain injury as the result of boxing in producing chronic encephalopathy is adequately justified by the many studies of live boxers and pathologic examinations of brains of former boxers made and recorded over the years since 1952. These indicate clearly a significant relationship between the numbers of bouts fought and the presence of severity of chronic encephalopathy. Because it is unlikely that currently adopted protective measures will substantially reduce these hazards, even though they have apparently reduced direct fatalities, a reasonable approach to prevention would be to reduce the number and severity of blows to the head. This might be done by making any blow to the head in boxing a foul and a reason for disqualification. Another approach would be the elimination of boxing.  相似文献   
36.
37.
A closed femur fracture pain model was developed in the C57BL/6J mouse. One day after fracture, a monoclonal antibody raised against nerve growth factor (anti-NGF) was delivered intraperitoneally and resulted in a reduction in fracture pain-related behaviors of approximately 50%. Anti-NGF therapy did not interfere with bone healing as assessed by mechanical testing and histomorphometric analysis. INTRODUCTION: Current therapies to treat skeletal fracture pain are limited. This is because of the side effect profile of available analgesics and the scarcity of animal models that can be used to understand the mechanisms that drive this pain. Whereas previous studies have shown that mineralized bone, marrow, and periosteum are innervated by sensory and sympathetic fibers, it is not understood how skeletal pain is generated and maintained even in common conditions such as osteoarthritis, low back pain, or fracture. MATERIALS AND METHODS: In this study, we characterized the pain-related behaviors after a closed femur fracture in the C57BL/6J mouse. Additionally, we assessed the effect of a monoclonal antibody that binds to and sequesters nerve growth factor (anti-NGF) on pain-related behaviors and bone healing (mechanical properties and histomorphometric analysis) after fracture. RESULTS: Administration of anti-NGF therapy (10 mg/kg, days 1, 6, and 11 after fracture) resulted in a reduction of fracture pain-related behaviors of approximately 50%. Attenuation of fracture pain was evident as early as 24 h after the initial dosing and remained efficacious throughout the course of fracture pain. Anti-NGF therapy did not modify biomechanical properties of the femur or histomorphometric indices of bone healing. CONCLUSIONS: These findings suggest that therapies that target NGF or its cognate receptor(s) may be effective in attenuating nonmalignant fracture pain without interfering with bone healing.  相似文献   
38.
39.
Auto-adjustable continuous positive airway pressure (APAP) devices are an emerging treatment alternative to fixed-pressure continuous positive airway pressure (CPAP) therapy for obstructive sleep apnoea syndrome. They have been engineered to automatically adjust the pressure to the optimal level on a continuous basis. However, not all APAP technologies use the same algorithm. Three different APAP devices (Autoset Spirit, Breas PV 10i and RemStar Auto) were compared in a randomised crossover trial in patients already established on fixed-pressure CPAP therapy. The outcome measures were compliance, quality of life and side-effects. Twenty-seven middle-aged patients (25 male) previously diagnosed with severe obstructive sleep apnoea syndrome (median (interquartile range) apnoea/hypopnoea index 48 (29-76)), established on CPAP therapy for >3 yrs, were randomised to each APAP device for 4 weeks. Mean pressure and patient compliance were significantly lower on the Breas PV 10i than on the other APAP devices. The devices were similar in terms of quality of life, daytime sleepiness and upper airway side-effects, but patients evaluated them significantly differently in terms of device features, sleep quality and pressure comfort, with the Breas PV 10i being the least popular. Auto-adjustable positive airway pressure devices differ in pressure delivery and patient compliance in obstructive sleep apnoea syndrome patients.  相似文献   
40.
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