全文获取类型
收费全文 | 257305篇 |
免费 | 12797篇 |
国内免费 | 256篇 |
专业分类
耳鼻咽喉 | 4076篇 |
儿科学 | 9895篇 |
妇产科学 | 7201篇 |
基础医学 | 37676篇 |
口腔科学 | 7367篇 |
临床医学 | 19958篇 |
内科学 | 47451篇 |
皮肤病学 | 7463篇 |
神经病学 | 23332篇 |
特种医学 | 11184篇 |
外国民族医学 | 55篇 |
外科学 | 40274篇 |
综合类 | 2202篇 |
一般理论 | 71篇 |
预防医学 | 13774篇 |
眼科学 | 6365篇 |
药学 | 17933篇 |
中国医学 | 517篇 |
肿瘤学 | 13564篇 |
出版年
2021年 | 1775篇 |
2020年 | 1558篇 |
2019年 | 2056篇 |
2018年 | 3896篇 |
2017年 | 3371篇 |
2016年 | 4389篇 |
2015年 | 4121篇 |
2014年 | 4737篇 |
2013年 | 7884篇 |
2012年 | 10390篇 |
2011年 | 11226篇 |
2010年 | 6522篇 |
2009年 | 4972篇 |
2008年 | 11295篇 |
2007年 | 12005篇 |
2006年 | 11875篇 |
2005年 | 11851篇 |
2004年 | 11259篇 |
2003年 | 11238篇 |
2002年 | 11058篇 |
2001年 | 12046篇 |
2000年 | 13240篇 |
1999年 | 9523篇 |
1998年 | 3036篇 |
1997年 | 2702篇 |
1996年 | 2251篇 |
1995年 | 1965篇 |
1994年 | 1864篇 |
1993年 | 1802篇 |
1992年 | 4643篇 |
1991年 | 4388篇 |
1990年 | 4353篇 |
1989年 | 4145篇 |
1988年 | 3630篇 |
1987年 | 3633篇 |
1986年 | 3400篇 |
1985年 | 3422篇 |
1984年 | 2692篇 |
1983年 | 2196篇 |
1982年 | 1553篇 |
1981年 | 1480篇 |
1979年 | 2408篇 |
1978年 | 1852篇 |
1977年 | 1642篇 |
1976年 | 1368篇 |
1975年 | 1674篇 |
1974年 | 1679篇 |
1973年 | 1612篇 |
1972年 | 1410篇 |
1971年 | 1354篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
The rate of ethanol elimination and blood acetate concentrationsafter a peroral dose of alcohol were measured in eight asthmaticpatients receiving high-dose corticosteroid, sustained releasetheophylline and beta-2-sympathicomimetic treatment and in eightnonalcoholic, healthy controls. Mean ethanol elimination rate(ER) and mean blood acetate concentration (AC) were significantly(P<0.01) higher in asthmatics (ER=134.8 ± 12.9 mg/kg/hr,AC = 1.13± 0.25 mM) than in controls (ER = 100.2 ±12.3 mg/kg/hr, AC = 0.64 ± 0.10 mM). In the asthmaticsthere was a significant negative correlation between the ageand the rate of ethanol elimination (r = 0.890, P <0.01); in the control group, however, this correlation was oflower degree (r = 0.423) and did not achieve statisticalsignificance. Enhanced ethanol metabolism in asthmatics is possiblydue to the effect of drugs. Our results suggest that ethanolelimination rate is increased in asthmatics receiving medicationand that the effect is most significant in younger age groups. 相似文献
22.
This study aimed at identifying the signal(s) that elicit myositis-induced neuroplastic changes in background activity and responsiveness of spinal neurones. It is based on previous data suggesting that in dorsal horn neurones, responsiveness to peripheral input on one hand and background activity on the other are probably controlled by different mechanisms. In anaesthetized rats, myositis was induced in the gastrocnemius-soleus muscle and the activity of single dorsal horn neurones was recorded in segment L3. Impulse traffic and axoplasmatic transport in dorsal roots L4 and L5 were selectively blocked by lignocaine or vinblastine for various time periods relative to the induction of the myositis. The results show that the main triggering signal for the myositis-induced changes in both responsiveness and background activity is the altered impulse activity in primary afferent fibres. In contrast, 'no axonally transported chemical signal controlling the discharge behaviour of dorsal horn neurones was found. However, the time course of the electrical signals that cause the myositis-induced changes in background activity and responsiveness is different. For changes in responsiveness, a rather narrow time window of 2 h directly after induction of the myositis existed, during which the impulses from the inflamed muscle must reach the spinal cord. Accordingly, to prevent the increase in responsiveness, the electrical input had to be blocked during the first 2 h; a block of the same duration at another time had no effect. The change in background activity seems to be due to a continuous input from the inflamed muscle which adds up over the hours. Therefore, with regard to background activity, blocking the electrical signals is effective at any time, but only a block of long duration has a significant effect. 相似文献
23.
24.
25.
The aqueous, organic, and volatile oil extracts of leaves of Eugenia uniflora Linn. Family Myrtaceae were investigated for antibacterial properties using agar dilution techniques. The aqueous extract was the most active against the organisms compared to the organic and volatile oil extracts. The extracts were found to inhibit Gram positive Staphylococcus aureus and Bacillus subtilis and Gram negative Escherichia coli and Shigella dysentcriae. Pseudomonas aeruginosa, Klebsiella pneumoniac, and Salmonella typhi were not inhibited. 相似文献
26.
27.
C. Sch?fer H. H. Klünemann B. Ibach J. Mueller A. Putzhammer I. Trender-Gerhard G. Schuierer H. E. Klein 《Der Nervenarzt》2002,24(1):879-882
Wir berichten über den ersten Fall von polyzystischer lipomembran?ser Osteodysplasie oder “brain, bone and fat disease” in
Deutschland. Die nach dem Erstbeschreibern auch als Morbus J?rvi-Hakola-Nasu bezeichnete Erkrankung ist bisher vor allem in
Japan und in Finnland beschrieben worden. Einzelne F?lle wurden aus Schweden, Norwegen, Italien, Südafrika, Belgien und den
USA berichtet. Im deutschsprachigen Raum ist bisher ein Fall aus ? ver?ffentlicht worden. 相似文献
28.
In comparative histological and cytological studies on 270 prostatic carcinoma patients highly and moderately differentiated tumors were found to be more frequent histologically than cytologically. An early and reliable sign of response to hormone therapy proved to be reticularization and vacuolization of the nuclear chromatin. Follow-up studies by means of multiple aspiration biopsies with cytologic examinations seem to be more reliable in prognostic terms than examination of the histological tumor structure. 相似文献
29.
30.