全文获取类型
收费全文 | 1427篇 |
免费 | 96篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 16篇 |
儿科学 | 39篇 |
妇产科学 | 10篇 |
基础医学 | 169篇 |
口腔科学 | 57篇 |
临床医学 | 220篇 |
内科学 | 235篇 |
皮肤病学 | 25篇 |
神经病学 | 80篇 |
特种医学 | 135篇 |
外科学 | 153篇 |
综合类 | 31篇 |
预防医学 | 213篇 |
眼科学 | 8篇 |
药学 | 97篇 |
肿瘤学 | 59篇 |
出版年
2021年 | 18篇 |
2019年 | 12篇 |
2018年 | 11篇 |
2017年 | 15篇 |
2016年 | 15篇 |
2015年 | 21篇 |
2014年 | 27篇 |
2013年 | 43篇 |
2012年 | 33篇 |
2011年 | 42篇 |
2010年 | 43篇 |
2009年 | 52篇 |
2008年 | 33篇 |
2007年 | 54篇 |
2006年 | 51篇 |
2005年 | 55篇 |
2004年 | 47篇 |
2003年 | 47篇 |
2002年 | 40篇 |
2001年 | 37篇 |
2000年 | 27篇 |
1999年 | 27篇 |
1998年 | 40篇 |
1997年 | 44篇 |
1996年 | 38篇 |
1995年 | 35篇 |
1994年 | 16篇 |
1993年 | 25篇 |
1992年 | 18篇 |
1991年 | 31篇 |
1990年 | 27篇 |
1989年 | 30篇 |
1988年 | 34篇 |
1987年 | 34篇 |
1986年 | 21篇 |
1985年 | 26篇 |
1984年 | 11篇 |
1983年 | 17篇 |
1982年 | 15篇 |
1981年 | 11篇 |
1980年 | 15篇 |
1978年 | 17篇 |
1977年 | 10篇 |
1976年 | 14篇 |
1974年 | 8篇 |
1929年 | 17篇 |
1928年 | 8篇 |
1924年 | 8篇 |
1922年 | 9篇 |
1921年 | 7篇 |
排序方式: 共有1547条查询结果,搜索用时 31 毫秒
1.
2.
3.
4.
5.
6.
E. Winslow J. K. Campbell L. Delbressine 《The Journal of pharmacy and pharmacology》1995,47(7):608-613
Org 20781, the major metabolite of Org 7797 found in in-vitro experiments was examined for antiarrhythmic and electrophysiological effects in-vivo. Org 20781 (0·5–2·0 mg kg?1 i.v.) inhibited the development of early ischaemia-induced arrhythmias in rats, suppressed spontaneous ventricular tachycardia (VT) in conscious dogs with 24-h old infarcts, and prevented electrical induction of VT in dogs with 5–6-day old infarcts, actions associated with slowing of conduction at all levels of the myocardium. Cardiac refractory periods were only modestly prolonged whilst repolarization was unchanged. Peak plasma levels of the parent compound (infused to total doses of 2–4mg kg?1) associated with suppression of late arrhythmias were 6–18 μm, whilst the mean plasma elimination half-life (in normal dogs) was 107 min. It was concluded that the major metabolite has a similar antiarrhythmic and electrophysiological profile to the parent compound, is at least half as potent and may contribute to the therapeutic effects of Org 7797 administration. 相似文献
7.
Kinnison ML; Perler BA; Kaufman SL; Mitchell SE; Kadir S; Williams GM; White RI Jr 《Radiology》1986,160(3):727-730
In situ saphenous vein grafts are being used with increasing frequency for bypass procedures involving the femoral and popliteal arteries. Complications of these procedures include anastomotic stenoses and persistent arteriovenous fistulae that may result in failure of the graft. Balloon angioplasty and embolotherapy with detachable balloons were employed successfully in three or four recent cases of patients with complications from in situ grafts. Tailored angiography is essential for evaluating in situ grafts, and interventional techniques are extremely useful for managing complications. 相似文献
8.
J K Campbell R T Logan R J Marshall G McGarry T Sleigh E Winslow 《Journal of medicinal chemistry》1986,29(2):244-250
The antiarrhythmic efficacy of 17 beta-amino- and 17 beta-amino-16 alpha-hydroxyestratrien-3-ols and 3-acetates (group 1) was compared with the efficacy of corresponding 3-[2-hydroxy-3-(isopropylamino)propyl] and 3-[2-hydroxy-3-(tert-butylamino)propyl] ethers (group II), substituents which are usually associated with beta-adrenoceptor blocking activity. Group I compounds exerted potent antiarrhythmic activity against both aconitine-induced arrhythmias in mice and ischemia-induced arrhythmias in rats and reduced the maximum following frequency of isolated guinea pig atria. Electrophysiological studies indicated that their mechanism of action is due to an ability to reduce the fast inward sodium current in cardiac cells (class I antiarrhythmic action). Group II compounds were inactive in the aconitine and atrial tests and electrophysiological studies confirmed that they were devoid of class I activity. However, these compounds, like both class I antiarrhythmic and beta-adrenoceptor blocking drugs, were active against ischemia-induced arrhythmias. Group II compounds, unlike group I compounds, exerted nonspecific beta-adrenoceptor blocking actions, which may account for their activity in the rat test. It was concluded that introduction of the 3-substituted ether group did not confer any advantage over the parent 3-ol or 3-acetate compounds. 相似文献
9.
10.
The acute effects of monoamine oxidase inhibitors L-deprenyl (0.5-5.0 mg/kg), clorgyline (1.0-10.0 mg/kg), and milacemide (100-400 mg/kg) on the behavior of adult male squirrel monkeys were examined during brief social separations beginning 60 min after subcutaneous drug administration. All three drugs selectively reduced the rate of calling during social separation at doses which did not affect time spent in locomotion, nor the frequency of vigilance-checking. Deprenyl and milacemide, but not clorgyline, produced concurrent decreases in locomotion at the higher doses tested. At threshold doses, clorgyline, but not deprenyl or milacemide, increased call duration and decreased call peak frequency compared to vehicle control values. Plasma levels of MHPG were decreased by an optimal dose of clorgyline but not by deprenyl or milacemide, indicating that substrate specificity was maintained at the drug doses employed. We conclude that different MAO substrates mediate different aspects of vocal and nonvocal behavior in adult male squirrel monkeys. 相似文献