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   398344篇
  免费   29481篇
  国内免费   10146篇
耳鼻咽喉   4339篇
儿科学   10013篇
妇产科学   7048篇
基础医学   30144篇
口腔科学   8614篇
临床医学   43586篇
内科学   46334篇
皮肤病学   5195篇
神经病学   20534篇
特种医学   9173篇
外国民族医学   37篇
外科学   39060篇
综合类   65619篇
现状与发展   25篇
一般理论   51篇
预防医学   38763篇
眼科学   5674篇
药学   37040篇
  571篇
中国医学   51230篇
肿瘤学   14921篇
  2024年   1296篇
  2023年   6606篇
  2022年   11376篇
  2021年   16182篇
  2020年   15262篇
  2019年   20171篇
  2018年   17675篇
  2017年   15217篇
  2016年   12821篇
  2015年   12002篇
  2014年   25308篇
  2013年   26005篇
  2012年   23220篇
  2011年   24908篇
  2010年   20072篇
  2009年   17887篇
  2008年   16879篇
  2007年   17546篇
  2006年   15072篇
  2005年   13003篇
  2004年   10589篇
  2003年   9248篇
  2002年   7222篇
  2001年   6520篇
  2000年   5404篇
  1999年   4583篇
  1998年   3690篇
  1997年   3527篇
  1996年   3023篇
  1995年   2845篇
  1994年   2714篇
  1993年   2114篇
  1992年   2155篇
  1991年   1878篇
  1990年   1653篇
  1989年   1449篇
  1988年   1378篇
  1985年   3835篇
  1984年   4839篇
  1983年   3359篇
  1982年   3829篇
  1981年   3574篇
  1980年   3185篇
  1979年   2919篇
  1978年   2540篇
  1977年   1918篇
  1976年   2157篇
  1975年   1636篇
  1974年   1432篇
  1973年   1280篇
排序方式: 共有10000条查询结果,搜索用时 125 毫秒
961.
胃幽门弯曲菌感染对胃癌发生影响的探讨   总被引:1,自引:1,他引:0  
应用Warthin-starry镀银技术检查胃幽门弯曲菌,对中国胃癌高发区及美国胃癌高发区新奥尔良检查了300例具有胃症状的胃粘膜标本。结果发现幽门弯曲菌阳性率为60~62%,并且看到这种细菌的感染与慢性胃炎病变的程度有明显的关系。本文探讨了幽门弯曲菌的感染与胃癌癌前病变的关系。  相似文献   
962.
为探讨临床中使用钙制剂抢救链霉素过敏休克病人有良好效果的原因,由被动血凝试验、被动皮肤过敏试验和ELISA法证实,Ca~( )可以抑制链霉素抗原-抗体的反应。这种抑制作用是通过Ca~( )链霉素抗原结合,封闭链霉素抗原决定簇来加以实现的。  相似文献   
963.
We have reviewed some of the factors which contribute to lung damage by various toxicants. These include disposition of the chemical, its metabolism, individual cell type susceptibility and the potential for the tissue to repair. We have discussed the use of biochemical parameters to measure the functional activity of individual cell types in order to predict the damage to specific cell types and concluded that careful morphological analysis of lung tissue is likely to provide a more sensitive and informative measure of specific cell type injury. However, in order to investigate the mechanism of toxicity of pulmonary toxicants it is essential to establish the primary biochemical event that leads to cell damage and morphological change. The importance of separating the relevant biochemical change(s) from the cascade of biochemical events associated with dead and dying cells and the reparative response of the lung is emphasised.This report results from a discussion sponsored and organised by the Advisory Subgroup in Toxicology (AST) of the European Science Foundation's Standing Committee for the European Medical Research Councils and held at the Medical Research Council Toxicology Unit, Carshalton, U. K. Those taking part were: W. N. Aldridge (AST; as above); J. Bignon (Unit for Research in Renal and Pulmonary Pathology, University of Paris, Creteil, France); P. H. Burri (Section of Developmental Biology, Institute of Anatomy, University of Berne, Switzerland); G. M. Cohen (as above); D. Dinsdale (MRC Toxicology Unit, Carshalton U. K.); P. Hedqvist (Dept. of Physiology, Karolinska Institute, Stockholm, Sweden); D. Henschler (AST; Dept. of Toxicology and Pharmacology, University of Wurzburg, FDR); G. J. Laurent (Biochemistry Unit, Cardiothoracic Institute, University of London, London, U. K.); R. Lauwerys (AST Industrial and Medical Toxicology Unit, University of Louvain, Brussels, Belgium); F. Lembeck (AST; Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); N. Lery (AST; Poison Control Centre, Lyon, France); P. Moldeus (Dept. of Forensic Medicine, Karolinska Institute, Stockholm, Sweden); B. Nemery (MRC Toxicology Unit, Carshalton, U. K.); A. Saria (Dept. for Experimental and Clinical Pharmacology, University of Graz, Austria); L. L. Smith (as above);B. Terracini (AST; Dept. of Pathology and Cancer Epidemiology, University of Turin, Italy)  相似文献   
964.
While an exacerbation in allergic symptoms corresponding to seasons has long been reported, few studies have investigated the association between the season of birth and allergic disorders. The aim of this study was to investigate whether the climatologic data before and after birth affected the incidence of atopic dermatitis (AD) and the results of allergy-related blood tests in early infancy. From February 1995 to January 2000, 2136 infants were tested for AD and followed for 12 months. AD patients were tested by using allergy-related blood tests. Data were compared according to the month of birth and the climatologic data using a computed statistical software package. Six hundred and thirty infants had AD before 12 months old, and significant differences were found according to the season of birth (p < 0.0001). Infants born in spring showed the lowest (22.3%) incidence, while those born in autumn showed the highest (34.6%). In 369 patients, total serum IgE levels, and serum specific IgE levels with egg white at 3 months old were also different according to the season of birth. All of these levels were lower in patients born in spring and summer, and higher in patients born in autumn and winter. Furthermore, the cumulative sunshine amount during the 3 months before and after birth was inversely correlated, while the average temperature over the 3 months before birth was positively correlated to the incidence of AD according to the month of birth. The climatologic data around birth may play an important role in whether an infant develops allergies.  相似文献   
965.
高效液相色谱法测定复方万年青胶囊中大黄素   总被引:1,自引:0,他引:1  
目的建立复方万年青胶囊中大黄素的含量测定方法。方法采用高效液相色谱(HPLC)法,以Diamonsil C18(4.6 mm×250 mm×5μm)为分析柱,甲醇-0.1%磷酸溶液(80∶20)为流动相,流速为1.0 ml/min,柱温为35℃,检测波长254 nm。结果大黄素在0.039~0.355μg范围内呈良好线性关系,r=1.0000。平均回收率为99.3%,RSD=0.4%(n=5)。结论HPLC法是一种简便、准确、可靠的分析方法。  相似文献   
966.
Objective To observe the clinical effect of Babaodan combined with transcatheter arterial chemoembolization (TACE) therapy for primary hepatocellular carcinoma. Methods Selected patients were randomly assigned to two groups. One group accepted TACE only and the other group accepted TACE and took 2 Babaodan capsules orally 3 times a day for 8 weeks. Results After 8 weeks' treatment, the size of the tumors and the alpha foetal protein (AFP) concentration in all the patients in the two groups diminished and was not significantly different between the two groups (P〉0.05). The ratio of stability and improvement in the traditional Chinese medicine (TCM) syndrome was higher in the Babaodan plus TACE group than it was in the TACE only group (P〈0.05). There were more complications in the TACE only group than in the Babaodan plus TACE group. The one-year survival rate in the Babaodan plus TACE group was higher than in the TACE group (P〈0.05). Conclusion Babaodan can improve TCM syndrome, reduce complications and prolong survival of patients with primary hepatocellular carcinoma.  相似文献   
967.
医疗侵权责任中的过失——论医师的注意义务   总被引:1,自引:0,他引:1  
罗秀  蒲川  王轶 《医学教育探索》2007,6(3):287-288,F0003
过失作为构成侵权行为的一个重要条件,在医疗侵权行为中主要表现为医师的过失,其本质是对“注意义务”的违反。因此正确认识医师的注意义务,对医疗侵权行为中的过失判断有着重要意义。  相似文献   
968.
目的:探讨加速儿童髋关节一过性滑膜炎疾病的愈合.方法:随机性分析2005年1月~2006年4月共100例髋关节一过性滑膜炎患儿的治疗效果,把病人随机分为治疗组及对照组.治疗组按常规方法治疗加TDP灯局部照射,对照组仅按常规方法治疗.结果:治疗1周后,治疗组B超检查增厚滑膜厚度变化差值、关节腔间隙宽度变化值、关节腔积液好转率、"4"字试验阴性率均明显优于对照组(P<0.05).结论:TDP灯用于治疗儿童髋关节一过性滑膜炎能加速疾病愈合,提高治疗效果.  相似文献   
969.
本文报告40例癫痫病人采用手术治疗。30例作了CT检查、脑电图检查,6例作脑电地形图检查,对手术定位有较大帮助。术中用脑皮层电图监测,有效地提高了癲痫源灶的切除率,手术有效者34例(85.0%)。作者还应用了胼胝体切开术,从病灶切除的病理所见,癫痫的外科治疗应引起神经外科的重视。  相似文献   
970.
Masumi Ichikawa   《Brain research》1987,420(2):253-258
The rearrangement of terminations from the bed nucleus of stria terminalis (BST) was examined in the medial amygdaloid nucleus (MAN) at 2 months following the lesion of the accessory olfactory bulb (AOB) using an electron microscopy and degeneration study. At 2 days following a BST lesion, the number of degenerating synapses was 0.7 ± 0.1 (mean±S.E.M.) per unit area (2500 μm2 in the molecular layer, and 3/0 ± 0.3 in the cellular part. At 2 months after an AOB lesion, the degenerating synapses from the AOB had completely disappeared from the MAN. The BST was then lesioned at 2 months after the AOB lesion and, 2 days following this BST lesion, the degenerating synapses were counted in MAN. The numbers observed were 3.3 ± 0.6 per unit area in the molecular layer and 4.5 ± 0.4 in the cellular part. Therefore, the number of these degenerating synapses increased significantly within the molecular layer, though, in the cellular part the number of synapses was not significantly elevated over control. No differences in postsynaptic profiles (ratio of synapses on dendritic spine to dendritic shaft) were observed after the AOB lesion. These results indicate that the BST fibers formed new synapses in the molecular layer following the denervation of AOB fibers. The possibility of new synapse formation by other afferent fibers in addition to the AOB fibers is discussed as is the relationship between lesion induced synaptic reorganization and functional recovery after injury.  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