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   129463篇
  免费   5154篇
  国内免费   274篇
耳鼻咽喉   2140篇
儿科学   3899篇
妇产科学   4532篇
基础医学   17529篇
口腔科学   3726篇
临床医学   7709篇
内科学   28044篇
皮肤病学   3738篇
神经病学   10808篇
特种医学   2777篇
外国民族医学   59篇
外科学   15411篇
综合类   609篇
一般理论   39篇
预防医学   13780篇
眼科学   3404篇
药学   10713篇
中国医学   373篇
肿瘤学   5601篇
  2023年   701篇
  2022年   797篇
  2021年   2466篇
  2020年   1195篇
  2019年   2411篇
  2018年   3942篇
  2017年   2484篇
  2016年   2405篇
  2015年   2746篇
  2014年   3148篇
  2013年   4889篇
  2012年   7912篇
  2011年   8150篇
  2010年   4178篇
  2009年   2998篇
  2008年   6519篇
  2007年   7042篇
  2006年   6899篇
  2005年   6778篇
  2004年   6388篇
  2003年   5959篇
  2002年   5567篇
  2001年   3914篇
  2000年   4119篇
  1999年   3275篇
  1998年   710篇
  1992年   1633篇
  1991年   1477篇
  1990年   1434篇
  1989年   1350篇
  1988年   1325篇
  1987年   1319篇
  1986年   1253篇
  1985年   1202篇
  1984年   926篇
  1983年   708篇
  1979年   1086篇
  1978年   653篇
  1977年   538篇
  1976年   563篇
  1975年   672篇
  1974年   1022篇
  1973年   978篇
  1972年   848篇
  1971年   794篇
  1970年   842篇
  1969年   817篇
  1968年   738篇
  1967年   633篇
  1966年   601篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
The nerve action potential at the elbow and somatosensory evoked potentials (SEPs) at the scalp were recorded over 30 minutes of tourniquet-induced limb ischaemia in 10 diabetic patients and 10 controls. According to the SEP changes, an increased resistance to nerve ischaemia in diabetic patients was observed. The pathways involved in SEP conduction are discussed.  相似文献   
102.

Background  

Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints.  相似文献   
103.
The results of treatment with intrauterine transfusion are presented. The analysis comprised 48 successful transfusions into 29 foetuses. The reference group consisted of 11 transfusions which proved nonfeasible or ineffective and 54 untreated cases. Following blood treatment, the newborn mortality rate dropped more than threefold. Long-term follow-up of 21 children generally showed their good physical and mental development. We also present 4 cases of supsequent pregnancies after intrauterine blood treatment in a preceding pregnancy, showing that it is possible to save the next baby of the same mother.  相似文献   
104.
105.
106.
Due to limited aqueous solubility of dorzolamide at physiologic pH, the pH of Trusopt eye drops (cont. 2% dorzolamide) has to be kept at about 5.65, and to increase the topical bioavailability of the drug from Trusopt the contact time of the drug with the eye surface is increased by increasing the viscosity of the eye drops to 100 cps. This low pH and high viscosity can lead to local irritation. In this study, dorzolamide hydrochloride was formulated as 2% and 4% low viscosity solutions (viscosity 3 to 5 cps) containing randomly methylated beta-cyclodextrin at pH 7.45. These formulations were evaluated in rabbits. The animals were sacrificed at various time points after topical administration of the drug and the dorzolamide concentration determined in the different parts of the eye. Trusopt was used as a reference standard. The topical availability of dorzolamide from the cyclodextrin-containing eye drops appeared to be comparable to that from Trusopt and the drug reached retina and optic nerve to give measurable concentrations for at least 8 h after administration of the eye drops.  相似文献   
107.
108.
Gallibacterium anatis (previously named Pasteurella haemolytica-like) is considered a normal inhabitant of genital and upper respiratory tracts of healthy chickens, but it is also associated with different pathological conditions. Secreted metalloproteases from field and reference G. anatis cultures were obtained by methanol precipitation and were characterized. Proteins of molecular mass higher than 100 kDa showing proteolytic activity were observed in 10% polyacrylamide gels copolymerized with 1% bovine casein. They were active at alkaline pH, and inhibited by ethylenediamine tetraacetic acid. Their activity was stable at 50 degrees C, but partially inhibited at 60 degrees C, and totally inhibited at higher temperatures. Secreted proteins were able to degrade chicken IgG after 24 h of incubation, and cross-reacted with a polyclonal antibody against purified protease from Actinobacillus pleuropneumoniae. Secreted metalloproteases could play a role in infections caused by G. anatis.  相似文献   
109.
PurposeTo analyze the electroclinical features, aetiology and outcome in patients with normal neurological examination and psychomotor development who presented seizures during a mild gastroenteritis (MG).Patients and methodsEvaluation of the clinical charts of 22 patients who were assessed in the Neurology Department, Hospital Nacional de Pediatría Prof. Dr. JP Garrahan between 1999 and 2007.ResultsTwelve patients were boys and 10 were girls, the age of onset ranged from 5 to 26 months, and the median age was 10 months. Rotavirus antigen test in stool was positive in 9 of 18 studied patients. The seizures were brief, focal with secondary generalization in 15 patients (68.5%), apparently generalized in 5 (22.5%) and focal in two (9%). Seven of the patients (35%) had more than one seizure in 24 h. The interictal EEG was normal in all patients. Neuroradiological studies were performed in 19 patients with a normal result. No patient was put on long-term treatment with antiepileptic drugs. Four patients had subsequent mild gastroenteritis and two of them presented convulsions during the disease. After between 12 and 67 months of follow-up, all patients had normal psychomotor development and neurological examination.ConclusionsIn this study we confirmed the association of benign infantile seizures (BIS) and MG with or without rotavirus. The identification of this entity allows avoiding unnecessary complementary studies and treatment with antiepileptic drugs.  相似文献   
110.
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