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   376708篇
  免费   34912篇
  国内免费   26150篇
耳鼻咽喉   2863篇
儿科学   4921篇
妇产科学   4195篇
基础医学   41176篇
口腔科学   6143篇
临床医学   52971篇
内科学   50853篇
皮肤病学   4150篇
神经病学   18211篇
特种医学   13868篇
外国民族医学   224篇
外科学   33289篇
综合类   70501篇
现状与发展   86篇
一般理论   31篇
预防医学   27666篇
眼科学   10755篇
药学   40800篇
  445篇
中国医学   25057篇
肿瘤学   29565篇
  2024年   1958篇
  2023年   5638篇
  2022年   14498篇
  2021年   18402篇
  2020年   14784篇
  2019年   11920篇
  2018年   12273篇
  2017年   11810篇
  2016年   10910篇
  2015年   16884篇
  2014年   20989篇
  2013年   19104篇
  2012年   28420篇
  2011年   31887篇
  2010年   21514篇
  2009年   17520篇
  2008年   21399篇
  2007年   21151篇
  2006年   20146篇
  2005年   19238篇
  2004年   12702篇
  2003年   12229篇
  2002年   10006篇
  2001年   8533篇
  2000年   8317篇
  1999年   8389篇
  1998年   5318篇
  1997年   5104篇
  1996年   3977篇
  1995年   3726篇
  1994年   3152篇
  1993年   2036篇
  1992年   2426篇
  1991年   2128篇
  1990年   1796篇
  1989年   1565篇
  1988年   1288篇
  1987年   1188篇
  1986年   963篇
  1985年   682篇
  1984年   372篇
  1983年   271篇
  1982年   143篇
  1981年   173篇
  1980年   118篇
  1979年   155篇
  1978年   76篇
  1977年   59篇
  1976年   39篇
  1974年   42篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
41.
Clinical analysis of 107 cases with chemical burns   总被引:1,自引:0,他引:1  
From 1978 to 1987 107 cases of chemical burns were treated. The patients were mainly young and middle age people (83.08%), with mean burned areas 17.8%. The majority of involved parts were low extremities. 57.44% of burned eyes became blind. Mean days in hospital were 43 days. Cure rate was 98.13% and death rate 1.87%. We emphasized that burned wounds must instantly be washed down with water, intoxication resulting from chemical matters must be effectively treated. Diagnosis of depth of burned wound by acids and means of prevention of chemical burns were also discussed.  相似文献   
42.
43.
44.
强化婴幼儿奶粉中叶酸的测定   总被引:1,自引:0,他引:1  
强化叶酸的奶粉在0.05M K_2HPO_4缓冲液中,经均质,调pH4.5,15000g离心20分钟,其清液调pH4.0,进行CGS树脂离子交换层析,用10ml KClK_2HPO_4洗脱,调pH7.0,进行HPLC测定,采用300x3.9mm ODS反相柱,移动相0.05M K_2HPO+MeOH(91+9),流速1ml/分,紫外检测器波长285nm,灵敏度0.0050D。方法相对标准偏差为±3.3%,回收率为87%,最小检测量为0.02μg/ml。  相似文献   
45.
46.
Y Q Li  W Yuan  S L Zhang 《中国中西医结合杂志》1992,12(12):719-21, 737, 708
Xiao Er Ke Chuan Ling Oral Liquid (KCL) is a Chinese herbal preparation consisted of 10 herbs such as Prunus armeniacae, Scutelaria baicalensis, Lonicera japonica etc. 30 children suffering from bronchopneumonia and/or acute bronchitis were treated with KCL (treated group) and another 30 cases were treated with penicillin and aminophylline (control group). Results: cure rate and effective rate in treated group was 26.6%, and 93.3% respectively. While in control group was 30% and 96.6% respectively. No significant differences were seen between them(P > 0.05). The pharmacodynamic experiment showed KCL had potent pharmacological action. The experiment on tracheal fragment of Guinea pig in vitro showed it caused moderately strong smooth muscle relaxation, through inhibition the effect of histamine and acetylcholine. Asthma induction experiment of Guinea pig in vivo showed KCL could significantly prolong the latent period of asthma and alleviate asthmatic symptom. Ammonium water cough induction experiment in mice showed it may apparently prolong cough latent period and reduce times of cough relapse and alleviate cough symptom. KCL had potent antipyretic effect on fever model induced by triple vaccine in rabbits. Bacteriostatic and antiviral experiment in vitro showed the drug had quite strong inhibitory effects for Streptococcus hemolyticus, Staphylococcus aureus, Flexners Dysentery bacillus, Diplococcus pneumoniae and Pseudomonas aeruginosa, and it could potently inhibit the respiratory syncytial virus. KCL is an effective drug in treating bronchopneumonia and acute bronchitis.  相似文献   
47.
影响脐血IgE值因素的研究   总被引:2,自引:0,他引:2  
目的 本研究对影响脐血IgE值的可疑因素进行分析 ,探讨影响儿童食物过敏的可疑因素。方法 选取孕期妇女 10 5名及其所生婴儿 ,采用标准问卷调查获取资料 ,对影响脐血IgE的因素进行分析。 结果 母亲的过敏性疾病史、父亲过敏性疾病史中的皮炎表现型、孕期妇女过敏性疾病发作史、有过敏史妇女孕后期摄入过量的牛奶和鸡蛋均与脐血IgE值的上升有关 ,且上述 5个因素对脐血IgE水平的影响依次降低。 结论 母亲的过敏性疾病史和父亲过敏性疾病史中的皮炎表现型是导致新生儿脐血IgE值升高的主要危险因素 ;同时 ,妊娠期加强对有过敏史妇女的保护 ,防止过敏性疾病的复发 ,在孕后期控制有过敏史妇女牛奶、鸡蛋等大分子食物致敏原的摄入 ,有助于降低脐血IgE值。  相似文献   
48.
49.
A difference spectrophotometric procedure is described for the assay of nitrazepam in tablet formulations. The method is based on the measurement of absorbance at 282 nm of a solution of the tablet extract in 0.1 M hydrochloric acid (pH 1) relative to that of an equimolar solution in 0.1 M sodium hydroxide (pH 13). The method is precise and selective for nitrazepam in the presence of the tablet excipients and 2-amino-5-nitrobenzophenone, the principal hydrolysis product of nitrazepam. The absence of a constant isosbestic point in the difference spectrum of nitrazepam during hydrolysis in alkaline solution indicates the presence of a previously unrecognized intermediate hydrolysis product.  相似文献   
50.
豚鼠内耳磁微粒栓塞缺血模型初探   总被引:3,自引:0,他引:3  
OBJECTIVE: To set up an inner ear ischemic model in guinea pig with ferromagnetic embolism. METHODS: A magnet was fitted in the external auditory canal and carbonyl iron filings (1%, 1 ml/kg) was injected into jugular, then the inner ear vessels were obstructed by ferromagnetic spheres. Cochlear blood flow (CBF) and number of red blood cells in the stria vessels were used to detect the model's ischemia of cochleae. The slice of temple bone and basal membrane stained by silver nitrate were used for inner ear's histopathological observations. RESULTS: The iron spheres were amassed in the one and two-day-later's model of inner ear vessels, which resulted in embolism. The number of red blood cells in the stria vessels decreased and then recovered to normal level after 4 days, but the CBF decreased to 50% +/- 10% of basic level immediately and recovered to 99% +/- 41% 4 days later. Scattered lesion of out hair cell cilium could be seen in cochleae in eight-day-later's model, and degenerations in different degree were found in vascular stria. CONCLUSION: The methods of inner ear ischemic model with ferromagnetic embolism could be practical and the decrease of CBF was reversible, so it may be an ideal model for studying some ischemic inner ear diseases and evaluating the effects of therapeutic drugs.  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