全文获取类型
收费全文 | 1613篇 |
免费 | 98篇 |
国内免费 | 114篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 70篇 |
妇产科学 | 15篇 |
基础医学 | 164篇 |
口腔科学 | 41篇 |
临床医学 | 289篇 |
内科学 | 409篇 |
皮肤病学 | 40篇 |
神经病学 | 44篇 |
特种医学 | 367篇 |
外国民族医学 | 1篇 |
外科学 | 86篇 |
综合类 | 42篇 |
预防医学 | 70篇 |
眼科学 | 12篇 |
药学 | 98篇 |
中国医学 | 1篇 |
肿瘤学 | 74篇 |
出版年
2023年 | 12篇 |
2022年 | 15篇 |
2021年 | 30篇 |
2020年 | 19篇 |
2019年 | 25篇 |
2018年 | 32篇 |
2017年 | 13篇 |
2016年 | 35篇 |
2015年 | 29篇 |
2014年 | 30篇 |
2013年 | 53篇 |
2012年 | 37篇 |
2011年 | 51篇 |
2010年 | 62篇 |
2009年 | 61篇 |
2008年 | 34篇 |
2007年 | 84篇 |
2006年 | 41篇 |
2005年 | 68篇 |
2004年 | 25篇 |
2003年 | 17篇 |
2002年 | 28篇 |
2001年 | 15篇 |
2000年 | 25篇 |
1999年 | 22篇 |
1998年 | 96篇 |
1997年 | 97篇 |
1996年 | 105篇 |
1995年 | 65篇 |
1994年 | 61篇 |
1993年 | 65篇 |
1992年 | 10篇 |
1991年 | 28篇 |
1990年 | 27篇 |
1989年 | 50篇 |
1988年 | 37篇 |
1987年 | 49篇 |
1986年 | 28篇 |
1985年 | 44篇 |
1984年 | 19篇 |
1983年 | 16篇 |
1982年 | 25篇 |
1981年 | 20篇 |
1980年 | 31篇 |
1979年 | 8篇 |
1978年 | 11篇 |
1977年 | 16篇 |
1976年 | 27篇 |
1975年 | 15篇 |
1974年 | 4篇 |
排序方式: 共有1825条查询结果,搜索用时 15 毫秒
1.
Experience with the 'skew flap' below-knee amputation 总被引:3,自引:0,他引:3
A review of 353 lower limb amputations over the last 7 years has been performed to assess the results of the skew flap myoplastic below-knee amputation which was introduced in April 1983 because of reported advantages in terms of wound healing and earlier ambulation. Comparing the first 3 1/2 year period with the second, the total number of amputations decreased by 31 per cent. The number of above-knee amputations remained similar in the two periods (82,62), whilst the number of Gritti-Stokes amputations fell from 79 to 21 (0.001 greater than P greater than 0.01). The proportion of below-knee (BK) amputations increased from 50 (23.7 per cent) to 59 (41.5 per cent) (0.01 greater than P greater than 0.025). The groups were comparable in terms of previous vascular surgery and co-existing medical conditions. The time to full stump healing was significantly shorter in the skew flap group compared with the earlier Burgess type BK amputation (P = 0.001), and there was a trend to fewer stump failures in the skew flap group. We therefore feel that the skew flap amputation gives superior results to the Burgess BK amputation in terms of healing and a lower complication rate, allowing a higher proportion of BK amputations to be performed. A prospective randomized trial of the two techniques is in hand to determine the accuracy of this hypothesis. 相似文献
2.
Summary— To investigate if the functional alterations observed in resistance arteries of spontaneously hypertensive rats (SHRs) were also present at the coronary level, in vitro experiments were performed in mesenteric resistance arteries (MRA) and in right (RIC) and left interventricular coronary (LIC) arteries taken from 15–25-week-old SHR and age-matched Wistar Kyoto rats WKYs. Using a passive extension protocol, internal diameters corresponding to 100 mmHg intraluminal pressure (D100) were determined and vessels were set up to a normalized internal diameter (0.9 D100). SHR mesenteric resistance arteries had a significantly smaller diameter compared to WKY arteries, whereas both types of SHR coronary arteries had a greater diameter compared to those of WKY rats. In arteries in the absence of contracting agonist, nitro-L-arginine (NOLA, 100 μM) induced a progressive rise in basal tone, which could be reversed by subsequent addition of L-arginine (100 μM) but not D-arginine (100 μM). When expressed as percent of maximal contractions induced by agonists (noradrenaline, NA [10 μM] in MRA; serotonin, 5-HT [10 μM], in RIC and LIC), these contractions were significantly stronger in WKY compared to SHR coronary and mesenteric resistance arteries. In NA-precontracted MRA and 5HT-precontracted coronary arteries in the presence of indomethacin (10 μM), the magnitude of acetylcholine-induced maximal relaxations (expressed as percent of maximal contractions induced by agonists) was greater in WKY compared to SHR arteries. After a 30-min incubation period, NOLA (100 μM) completely inhibited relaxations induced by acetylcholine (0.01–10 μM) in all types of precontracted arteries. Subsequent additions of sodium nitroprusside, (SNP, 10 μM) induced complete relaxations in all preparations. These results show that a basal release of NO or NO-like compound by endothelial cells is present in isolated mesenteric resistance and coronary arteries of WKY rats and SHRs. The contribution of endothelium-derived relaxing factor-nitric oxide (EDRF-NO) to arterial tone was lower in MRA compared to coronary arteries in both strains and in SHR compared to WKY arteries. In the SHR preparations, the impaired relaxation induced by acetylcholine appeared to be due to a functional alteration of the endothelium in the presence of normal reactivity of the smooth muscle cells. 相似文献
3.
4.
5.
表小檗碱对α受体的作用 总被引:2,自引:0,他引:2
表小檗碱(epiberberine,EB)是从湖北产黄连(Coptis chinensis Franch)中提取的一种生物碱,属苯喹嗪类原小檗碱,对其药理作用的研究资料甚少,未见其对α肾上腺素体作用的报道。资料表明,许多原小檗碱类化合物有α受体阻滞作用,为从该类化合物中选择 相似文献
6.
7.
8.
9.
Pernes JM; Vitoux JF; Brenoit P; Raynaud A; Parola JL; Roth JP; Angel CY; Fiessinger JN; Roncato M; Gaux JC 《Radiology》1986,158(2):481-485
Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs. 相似文献
10.
Keyvan Karkouti Duminda N Wijeysundera Terrence M Yau Jeannie L Callum Massimiliano Meineri Marcin Wasowicz Stuart A McCluskey W. Scott Beattie 《Journal canadien d'anesthésie》2006,53(3):279-287
PURPOSE: To determine the independent relationship between leukoreduced platelet transfusions and adverse events in cardiac surgery. METHODS: In this observational study, detailed baseline and perioperative data were prospectively collected on consecutive patients who underwent cardiac surgery at a single institution from 1999 to 2004. The independent associations of platelet transfusion with clinical outcomes (low output syndrome, myocardial infarction, stroke, renal failure, sepsis, and death) were determined by multivariable logistic regression analysis and propensity score case-control analysis. RESULTS: Of the 11,459 patients analyzed, 2,174 (19%) received (leukoreduced) platelets - 1,408 received 5 U, 471 received 10 U, 140 received 15 U, and 155 received 20 or more units. Although all measured adverse event rates were higher in those who received platelets, in neither the logistic regression analyses nor the propensity score analyses was there any association between platelet transfusion and any of the adverse events. CONCLUSIONS: Transfusion of leukoreduced platelets in cardiac surgery is not associated with adverse clinical outcomes when adjustments are made for important confounders. 相似文献