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   9496篇
  免费   506篇
  国内免费   173篇
耳鼻咽喉   70篇
儿科学   125篇
妇产科学   143篇
基础医学   404篇
口腔科学   131篇
临床医学   1173篇
内科学   653篇
皮肤病学   46篇
神经病学   253篇
特种医学   330篇
外科学   2141篇
综合类   1677篇
现状与发展   1篇
一般理论   1篇
预防医学   1976篇
眼科学   88篇
药学   667篇
  6篇
中国医学   128篇
肿瘤学   162篇
  2024年   9篇
  2023年   90篇
  2022年   201篇
  2021年   303篇
  2020年   249篇
  2019年   227篇
  2018年   204篇
  2017年   262篇
  2016年   236篇
  2015年   256篇
  2014年   456篇
  2013年   642篇
  2012年   498篇
  2011年   603篇
  2010年   440篇
  2009年   403篇
  2008年   465篇
  2007年   530篇
  2006年   487篇
  2005年   400篇
  2004年   348篇
  2003年   339篇
  2002年   290篇
  2001年   257篇
  2000年   220篇
  1999年   175篇
  1998年   162篇
  1997年   133篇
  1996年   137篇
  1995年   108篇
  1994年   137篇
  1993年   113篇
  1992年   97篇
  1991年   92篇
  1990年   99篇
  1989年   75篇
  1988年   80篇
  1987年   58篇
  1986年   47篇
  1985年   52篇
  1984年   36篇
  1983年   25篇
  1982年   38篇
  1981年   22篇
  1980年   24篇
  1979年   20篇
  1978年   13篇
  1977年   9篇
  1975年   4篇
  1972年   1篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
61.
N. M. Gajraj  MB  BS  FRCA    S. K. Sharma  MB  BS  FRCA    A. J. Souter  MB  BS  FRCA    Y. Pole  MB  BS  FRCA    J. E. Sidawi  MD   《Anaesthesia》1995,50(8):740-741
  相似文献   
62.
电针改善硬膜外吗啡用于术后镇痛所引起的免疫抑制   总被引:1,自引:1,他引:0  
为观察硬膜外吗啡和电针对术后患者免疫功能的影响,检测自然杀伤细胞(NKcell)活性和PHA诱导白细胞介素2(IL-2)水平在单纯胆囊切除术患者术前和术后第1、3、7天的动态变化情况。结果吗啡组NK活性在术后第1、3、7天抑制,手术组仅在术后第1、3天出现抑制,而抑制率低于同天的吗啡组,电针可拮抗吗啡引起的NK活性抑制加深状况。在术后第1天,手术组和吗啡组IL-2水平均下降,吗啡+电针组无明显变化,术后第7天吗啡+电针组IL-2升高接近正常人水平。表明电针能改善硬膜外吗啡引起的免疫抑制,促进术后机体的恢复。硬膜外吗啡结合电针是值得推荐的术后镇痛方法。  相似文献   
63.
64.
煤烟型大气污染对儿童肺功能的影响   总被引:4,自引:1,他引:3  
为观察煤烟型大气污染对儿童健康的影响 ,选择了太原市 3个污染程度不同地区的 45 0名儿童进行肺功能测试和问卷调查。研究结果显示 ,儿童呼吸功能表现为重度污染区 <中度污染区 <相对清洁区 ;肺通气功能阻塞性异常率表现为重度污染区 >中度污染区 >相对清洁区 ;Logistic回归分析发现肺通气功能阻塞性异常率与小学生家庭的取暖方式、厨房和卧室是否分开以及污染物的水平有关 ;多元线性回归分析显示重度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 65 80ml、119 2 7ml,中度污染区儿童的FVC、FEF5 0与相对清洁区相比分别减少了 5 7 2 8ml和 114 2 9ml;Ln(SO2 )每升高一个单位 ,FVC和FEF5 0分别减少69 10ml和 119 79ml,Ln(PM1 0 )每升高一个单位 ,FVC、FEF5 0等分别减少了 193 5 0ml和 171 69ml。结果提示 ,太原市煤烟型大气污染对儿童呼吸系统产生了危害。  相似文献   
65.
A follow-up investigation was performed on 49 female workers studied 2 years earlier in a vegetable-pickling plant. Acute and chronic respiratory symptoms and ventilatory capacity measurements were recorded during the original and the follow-up studies. Maximal expiratory flow-volume (MEFV) curves were recorded during the Monday morning work shift. The forced vital capacity (FVC), 1-s forced expiratory volume (FEV1), and flow rates at 50% and the last 25% of the FVC (FEF50, FEF25) were measured. There were small increases in the prevalence of chronic symptoms between the two studies for both smokers and nonsmokers, but these did not reach statistical significance. Five workers at the time of the initial study had a diagnosis of occupational asthma; only one of these was still working at the time of follow-up. Workers lost to the follow-up had lower lung function than those seen at follow-up. In workers who were followed, larger than expected mean annual declines were noted for all ventilatory capacity parameters in both smokers (FVC 0.070 l, FEV1 0.070 l; FEF50 0.355 l/s, FEF25 0.270 l/s) and nonsmokers (FVC 0.045 l, FEV1 0.045 l, FEF50 0.285 l/s; FEF25 0.130 l/s). The decrease was particularly pronounced for FEF50 and FEF25. The accelerated decline in ventilatory capacity tests noted in the female nonsmokers suggests an independent effect on lung function of work exposure in this environment. Our data confirm that work in the pickling industry, particularly in small, poorly regulated plants, has deleterious effects on respiratory function. Received: 24 September 1996 / Accepted: 19 June 1997  相似文献   
66.
Summary In order to assess whether the indications for conservative treatment of supratentorial epidural haematomas are applicable also to posterior fossa epidural haematomas (PFEDH), the author reviewed the records of 25 patients. With a PFEDH volume of no more than 10 ml, a thickness of no more than 15 mm, a midline shift of no more than 5 mm, and in the absence of a significant intracranial haematoma elsewhere on computed tomography (CT) scans, the patients undergoing conservative treatment achieved the same excellent outcome as those undergoing early surgery. These CT criteria for conservative treatment of PFEDHs are similar to those of supratentorial epidural haematomas except the volume factor, namely, 10 ml in the former against 30 ml in the latter. That means a PFEDH of 10 ml or larger in the small posterior fossa may produce the same degree of midline shift and compression, and be as dangerous as an epidural haematoma of 30 ml or larger in the more capacious supratentorial compartment. But also for epidural haematomas of the posterior fossa, which initially are smaller than 10 ml, the general rule remains valid that they should be under close clinical supervision  相似文献   
67.
Changes in the nerve fibers of the spinal cord were studied in rat experimental epidural tumor models. Light microscopy showed demyelinization in all with rats paraparesis and paraplegia. Cross-sectional views of nerve fibers stained with 3,3dipentyloxacarbo-cyanine iodide, obtained by confocal laser scanning microscopy, showed distorted, shrunken fibers with a low fluorescence intensity. Changes in the electrolyte contents of nerve fibers were studied by electron probe X-ray microanalysis. The K concentration in axons and the myelin sheath was increased in the paraparesis group, but was decreased in the paraplegia group. These findings suggest that, in the paraparesis group, compression of the spinal cord damaged cell membrane channels, which subsequently caused an increase in intracellular K, a decline in the action potential, and low-intensity fluorescence of nerve fibers. On the other hand, in the paraplegia group, destruction of cell membranes caused a decrease in intracellular K until it approached the extracellular level. This reduced both the action potential and the fluorescence intensity. As Ca and Mg concentrations in both axons and the myelin sheath increased in relation to the severity of neurologic damage, it appears that these electrolytes may also play an important role in damage to nerve fibers.  相似文献   
68.
Epidural abscess is a well-recognised but rare complication of epidural catheter placement. We have found only five previous reports of epidural abscess from noncatheter-related administration of steroids and/or local anaesthetic. We describe a further case which led to critical illness and emphasise the association between diabetes mellitus and epidural infection.  相似文献   
69.
Depth of epidural space in children   总被引:1,自引:0,他引:1  
M. A. Hasan  MB  ChB  DA  FRCA    R. F. Howard  BSc  MB  ChB  FRCA    A. R. Lloyd-Thomas  MB  BS  FRCA   《Anaesthesia》1994,49(12):1085-1087
  相似文献   
70.
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