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   2541篇
  免费   112篇
  国内免费   33篇
耳鼻咽喉   18篇
儿科学   120篇
妇产科学   28篇
基础医学   446篇
口腔科学   102篇
临床医学   303篇
内科学   564篇
皮肤病学   112篇
神经病学   67篇
特种医学   279篇
外科学   236篇
综合类   60篇
预防医学   107篇
眼科学   29篇
药学   153篇
中国医学   1篇
肿瘤学   61篇
  2015年   33篇
  2014年   27篇
  2013年   82篇
  2012年   33篇
  2011年   30篇
  2010年   51篇
  2009年   37篇
  2008年   36篇
  2007年   62篇
  2006年   65篇
  2005年   41篇
  2004年   27篇
  2003年   45篇
  2002年   26篇
  2001年   48篇
  2000年   36篇
  1999年   39篇
  1998年   88篇
  1997年   101篇
  1996年   107篇
  1995年   76篇
  1994年   77篇
  1993年   82篇
  1992年   48篇
  1991年   43篇
  1990年   54篇
  1989年   71篇
  1988年   68篇
  1987年   59篇
  1986年   57篇
  1985年   47篇
  1984年   58篇
  1983年   33篇
  1982年   35篇
  1981年   38篇
  1980年   52篇
  1979年   26篇
  1978年   32篇
  1977年   38篇
  1976年   41篇
  1975年   43篇
  1972年   28篇
  1971年   25篇
  1970年   28篇
  1965年   50篇
  1964年   53篇
  1963年   47篇
  1962年   41篇
  1961年   40篇
  1960年   65篇
排序方式: 共有2686条查询结果,搜索用时 15 毫秒
61.
Objective: Normal auditory systems appear well habituated to time/phase delays inherent to sound encoding along the hearing organ, sending frequency information non-simultaneously to the central auditory system. Eliminating, or simply perturbing, the cochlear delay might be expected to decrease speech recognition ability, especially under demanding listening conditions. Resources of a larger-scale investigation permitted a preliminary examination of this issue, particularly on a relevant timescale of empirically demonstrated cochlear delays. Design: In a randomized controlled trial study, word recognition was tested for mono-syllabic tokens treated digitally to exacerbate, if not diminish/nullify, such delays. Speech-weighted noise was used to interfere with listening to time-frequency reversed (nominally no delay) versus non-reversed (natural timing) transforms under three treatments of speech tokens: (1) original-digitally recorded; digitally processed to emphasize (2) transient versus (3) quasi-steady-state components. Study sample: Ten normal-hearing young-adult females. Results: The findings failed to demonstrate statistically significant differences between delay conditions for any of the three speech-token treatments. Conclusions: An algorithm putatively diminishing frequency-dependent cochlear delays failed to systematically deteriorate performance in all subjects for the fixed time-frequency transform, stimulus parameters, and test materials employed. Yet, trends were evident such that some effect of perturbing cochlear delays could not be ruled out completely.  相似文献   
62.
63.
64.
65.
This is the second part of a two‐part piece on self‐adhesive resin cements; Part I was presented in the previous issue of the Journal. Here in Part II, the specific topics concerning self‐adhesive cements are clinical performance, post‐cementation sensitivity, and cementation of endodontic posts.  相似文献   
66.
Nodding Syndrome is a poorly understood neurologic disorder of unknown aetiology that affects children and adolescents in Africa. Recent studies have suggested that the head nods are due to atonic seizures and Nodding Syndrome may be classified as probably symptomatic generalised epilepsy. As part of the Ugandan Ministry of Health clinical management response, a multidisciplinary team developed a manual to guide the training of health workers with knowledge and skills to manage the patients. In the absence of a known cause, it was decided to offer symptomatic care. The objective is to relieve symptoms, offer primary and secondary prevention for disability and rehabilitation to improve function. Initial management focuses on the most urgent needs of the patient and the immediate family until ‘stability’ is achieved. The most important needs were considered as seizure control, management of behavioural and psychiatric difficulties, nursing care, nutritional and subsequently, physical and cognitive rehabilitation. This paper summarises the processes by which the proposed guidelines were developed and provides an outline of the specific treatments currently being provided for the patients.  相似文献   
67.
68.

INTRODUCTION

No national recording systems for knife injuries exist in the UK. Understanding the true size and nature of the problem of knife injuries is the first stage in reducing the burden of this injury. The aim of this study was to survey every knife injury seen in a single inner city emergency department (ED) over a one-year period.

METHODS

A cross-sectional observational study was performed of all patients attending with a knife injury to the ED of a London major trauma centre in 2011. Demographic characteristics, patterns of injury, morbidity and mortality data were collected.

RESULTS

A total of 938 knife injuries were identified from 127,191 attendances (0.77% of all visits) with a case fatality rate of 0.53%. A quarter (24%) of the major trauma team’s caseload was for knife injuries. Overall, 44% of injuries were selfreported as assaults, 49% as accidents and 8% as deliberate self-harm. The highest age specific incident rate occurred in the 16–24 year age category (263/100,000). Multiple injuries were seen in 19% of cases, of which only 81% were recorded as assaults. The mean length of stay for those admitted to hospital was 3.04 days. Intrathoracic injury was seen in 26% of cases of chest trauma and 24% of abdominal injuries had a second additional chest injury.

CONCLUSIONS

Violent intentional injuries are a significant contributory factor to the workload of the major trauma team at this centre. This paper contributes to a more comprehensive understanding of the nature of these injuries seen in the ED.  相似文献   
69.
The Gay Bowel Syndrome   总被引:4,自引:0,他引:4  
Our experience in the management of 260 male homosexuals with coloreetal problems is described. The increased incidence of amebiasis, shigellosis and hepatitis, specific and nonspecific protocolitides, venereal disease and anal warts, is emphasized. It is important to recognize homosexual patients and the conditions to which they are predisposed.  相似文献   
70.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts   总被引:2,自引:0,他引:2  
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction.  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