全文获取类型
收费全文 | 194122篇 |
免费 | 4048篇 |
国内免费 | 443篇 |
专业分类
耳鼻咽喉 | 2749篇 |
儿科学 | 7456篇 |
妇产科学 | 5871篇 |
基础医学 | 25131篇 |
口腔科学 | 5747篇 |
临床医学 | 15322篇 |
内科学 | 34737篇 |
皮肤病学 | 4491篇 |
神经病学 | 11542篇 |
特种医学 | 10588篇 |
外国民族医学 | 97篇 |
外科学 | 29021篇 |
综合类 | 1101篇 |
一般理论 | 1篇 |
预防医学 | 16411篇 |
眼科学 | 4281篇 |
药学 | 13542篇 |
2篇 | |
中国医学 | 142篇 |
肿瘤学 | 10381篇 |
出版年
2018年 | 3494篇 |
2017年 | 3874篇 |
2016年 | 3151篇 |
2015年 | 4826篇 |
2014年 | 4238篇 |
2013年 | 3329篇 |
2012年 | 9730篇 |
2011年 | 4625篇 |
2010年 | 2120篇 |
2009年 | 3821篇 |
2008年 | 2001篇 |
2007年 | 2721篇 |
2006年 | 2989篇 |
2005年 | 11118篇 |
2004年 | 12597篇 |
2003年 | 8186篇 |
2002年 | 3408篇 |
2001年 | 4339篇 |
2000年 | 1693篇 |
1999年 | 5839篇 |
1998年 | 514篇 |
1995年 | 387篇 |
1992年 | 6882篇 |
1991年 | 7117篇 |
1990年 | 7357篇 |
1989年 | 6961篇 |
1988年 | 6487篇 |
1987年 | 6246篇 |
1986年 | 5966篇 |
1985年 | 5265篇 |
1984年 | 3604篇 |
1983年 | 2917篇 |
1982年 | 1008篇 |
1981年 | 771篇 |
1980年 | 842篇 |
1979年 | 3846篇 |
1978年 | 2368篇 |
1977年 | 1784篇 |
1976年 | 1567篇 |
1975年 | 2478篇 |
1974年 | 3112篇 |
1973年 | 2747篇 |
1972年 | 2761篇 |
1971年 | 2744篇 |
1970年 | 2558篇 |
1969年 | 2473篇 |
1968年 | 2244篇 |
1967年 | 2166篇 |
1966年 | 1899篇 |
1965年 | 1132篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
981.
Allogenic transplants have an established place in reconstructive procedures. For years it has been suspected that lyophilized dura mater can transmit Creutzfeld-Jakob disease. HIV infection with fully manifest AIDS and a mortality of up to 100% is now also increasing in significance. It is necessary to assess the risk of transferring HIV with allogenic transplants because HIV passes into the cell via specific surface receptors and is integrated within the chromosome. Experimental data on disinfection and sterilization of allogenic transplants stored within chromosomes and their inactivation are not available. Allogenic transplants are only used in operations for life-threatening disease. As a rule, these are elective operations which must meet the highest safety standards, also with regard to the danger of infection. Collaboration with a transplantation team is essential. 相似文献
982.
J P Desc?teaux 《Revue scientifique et technique (International Office of Epizootics)》1992,11(4):1071-1077
The results of a serological survey of a free-living population of meadow voles (Microtus pennsylvanicus) in Pinawa, Manitoba (Canada) showed that these animals possessed antibodies to six of the eleven viruses tested for, namely: reovirus type 3, murine encephalomyelitis agent, ectromelia virus, murine adenovirus, murine hepatitis virus and lymphocytic choriomeningitis virus. The significant increase in the number of individuals possessing specific antibodies suggests that these viruses, or related viruses, may be responsible for the decline in the population studied. 相似文献
983.
A 4-year-old girl presented with an intramedullary epidermoid cyst of the cervical spinal cord. The clinical, radiological, and surgical features and a brief critical review of the literature are included in this report. The cyst contents were removed totally in two operations. The child had a coexisting neuroenteric cyst in the posterior mediastinum. To our knowledge, this coexistence has not been previously reported. Contemporary imaging modes and prospects of the surgical treatment are discussed. 相似文献
984.
The article deals with the technical aspects of operation for extirpation of the esophagus through a cervico-abdominal approach in carcinoma (133 operations) and benign esophageal strictures (117 operations) with one-stage plastics by means of an isoperistaltic tube formed from the greater curvature of the stomach. The relative safety (2.8% of patients died) and high efficacy of the described operation allow it to be recommended for wide introduction into the practice of institutions engaged in surgery of the esophagus. 相似文献
985.
Sulphasalazine inhibition of human granulocyte activation by inhibition of second messenger compounds. 总被引:1,自引:0,他引:1 下载免费PDF全文
The effects of sulphasalazine on the production of second messenger compounds in human granulocytes have been characterised by various stimuli. The increases in cytosolic calcium, inositol trisphosphate, diacylglycerol, and phosphatidic acid (all important mediators of intracellular signal transduction) triggered by stimulation were inhibited by sulphasalazine. The metabolites 5-amino-salicylic acid and sulphapyridine were less potent inhibitors than the mother compound. It is concluded that sulphasalazine inhibits the synthesis of phosphoinositide derived second messenger compounds at the level of phospholipase C or its regulatory guanosine 5'-triphosphate (GTP) binding protein. Inhibition of phosphatidic acid synthesis was either due to the same mechanism, or to interaction with a phospholipase D regulating GTP binding protein. 相似文献
986.
987.
The effects of the enantiomers of 5-fluoro-8-hydroxy-2-(dipropylamino)tetralin, UH-301 and the potent 5-HT1A-receptor agonist (R)-8-hydroxy-2-(dipropylamino)tetralin, (R)-8-OH-DPAT, on locomotion, rearing and total activity were studied in rats. The experiments were performed as tests either of exploratory activity in non-habituated rats or of motor activity of rats habituated to the environment for 2 h before drug injection. (R)-8-OH-DPAT increased locomotion and total activity and decreased rearing in both conditions. (R)-UH-301 increased locomotion and slightly also total activity in habituated rats and decreased rearing in both conditions. (S)-UH-301 decreased locomotion and rearing in both conditions but only in doses of 10 mumol/kg and above. Lower doses of (S)-UH-301 (10 mumol/kg) antagonized (R)-8-OH-DPAT-induced increases of locomotion and total activity. As (S)-UH-301 decreased rearing, per se, it was not able to antagonize the (R)-8-OH-DPAT induced decrease. These results further support previous data that (S)-UH-301 is a 5-HT1A antagonist while (R)-UH-301 is a 5-HT1A agonist. 相似文献
988.
989.
G N Tsybuliak O S Nasonkin A V Chech?tkin 《Vestnik khirurgii imeni I. I. Grekova》1992,148(5):192-199
The infusion of hypertonic solution is thought by the authors to be effective due to its reflectory action for treatment of patients who are in the state of anaphylactic and cardiogenic shock. This method seems to be expedient for massive blood loss under conditions of prehospital medical aid to victims with very low level of arterial pressure, with craniocerebral trauma and critical trauma of the chest. 相似文献
990.
Bronchial hyperresponsiveness to methacholine in patients with primary Sj?gren's syndrome. 总被引:2,自引:2,他引:0 下载免费PDF全文
B Gudbj?rnsson H Hedenstr?m G St?lenheim R H?llgren 《Annals of the rheumatic diseases》1991,50(1):36-40
The prevalence of bronchial hyperresponsiveness (BHR) to methacholine inhalation in a consecutive series of 21 patients with primary Sjögren''s syndrome was studied prospectively. Slight to severe BHR was seen in 12/20 (60%) of the patients. Ten of 12 patients with BHR (83%) had a non-productive cough, wheezing, or intermittent breathlessness. Bronchial hyperresponsiveness was more common in patients with extraglandular symptoms (10/14, 71%) than in those with only glandular symptoms (29%). Spirometrically 29% (6/21) of the patients had ''small airways'' disease'', and all those had BHR. Of 6/21 (29%) who had diffuse interstitial lung disease, two had BHR. Three of the four patients with obstructive lung function were challenged with methacholine and two of them had BHR. Only two patients with BHR had normal spirometry findings. The data showed that respiratory disease--mostly mild or moderate but even severe bronchial hyperresponsiveness--is commonly seen in patients with primary Sjögren''s syndrome. 相似文献