全文获取类型
收费全文 | 844篇 |
免费 | 27篇 |
国内免费 | 47篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 41篇 |
妇产科学 | 24篇 |
基础医学 | 77篇 |
口腔科学 | 12篇 |
临床医学 | 100篇 |
内科学 | 216篇 |
皮肤病学 | 53篇 |
神经病学 | 23篇 |
特种医学 | 144篇 |
外科学 | 88篇 |
综合类 | 26篇 |
预防医学 | 7篇 |
眼科学 | 5篇 |
药学 | 67篇 |
中国医学 | 3篇 |
肿瘤学 | 30篇 |
出版年
2023年 | 2篇 |
2021年 | 4篇 |
2020年 | 3篇 |
2019年 | 2篇 |
2018年 | 6篇 |
2017年 | 7篇 |
2016年 | 5篇 |
2015年 | 21篇 |
2014年 | 16篇 |
2013年 | 20篇 |
2012年 | 13篇 |
2011年 | 14篇 |
2010年 | 36篇 |
2009年 | 33篇 |
2008年 | 18篇 |
2007年 | 58篇 |
2006年 | 22篇 |
2005年 | 18篇 |
2004年 | 12篇 |
2003年 | 18篇 |
2002年 | 26篇 |
2001年 | 20篇 |
2000年 | 10篇 |
1999年 | 14篇 |
1998年 | 48篇 |
1997年 | 49篇 |
1996年 | 61篇 |
1995年 | 31篇 |
1994年 | 31篇 |
1993年 | 22篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1990年 | 14篇 |
1989年 | 37篇 |
1988年 | 28篇 |
1987年 | 26篇 |
1986年 | 23篇 |
1985年 | 16篇 |
1984年 | 17篇 |
1983年 | 9篇 |
1982年 | 16篇 |
1981年 | 11篇 |
1980年 | 14篇 |
1979年 | 9篇 |
1978年 | 6篇 |
1977年 | 6篇 |
1976年 | 6篇 |
1975年 | 7篇 |
1931年 | 1篇 |
1925年 | 1篇 |
排序方式: 共有918条查询结果,搜索用时 15 毫秒
41.
42.
43.
LeRoy AJ; Williams HJ Jr; Bender CE; Segura JW; Patterson DE; Benson RC 《Radiology》1985,155(1):83-85
Two patients had colonic perforation as a result of percutaneous nephrostomy placement followed by track dilatation and renal calculus removal. We present the technical aspects of nephrostomy placement and stone removal, as well as the clinical diagnosis and management of these cases. Both patients recovered well with conservative therapy and required no surgical intervention. This report reviews the anatomic considerations for percutaneous nephrostomy in patients undergoing renal stone removal. 相似文献
44.
45.
Deterioration of plasma membrane is associated with activated caspases in human spermatozoa 总被引:11,自引:0,他引:11
Spermatozoa with deteriorated plasma membranes can be separated by magnetic-activated cell sorting (MACS) after binding superparamagnetic annexin V-conjugated microbeads (ANMBs) to membrane phosphatidylserine (PS). Semen samples from 15 donors and 25 infertile patients were divided into 2 spermatozoal fractions by annexin V-MACS. Activated caspases (aCPs), which mediate degradations of cell quality, were determined by CaspaTag in the 2 subpopulations. Spermatozoa from donors showed lower levels of bound annexin V (3.6% +/- 0.5% vs 11.9% +/- 1.1%; P <.01) and aCPs (21.8% +/- 2.6% vs 43.2% +/- 2.1%; P <.01) than did spermatozoa from infertile patients. MACS resulted in a decrease of spermatozoa with aCPs from 21.8% +/- 2.6% (before separation) to 9.2% +/- 1.4% (in the ANMB-negative fraction) in donors and from 43.2% +/- 2.1% to 18.8% +/- 2.6% in infertile patients (mean +/- SEM; P <.01). Separation effects of the MACS technique were confirmed with flow cytometry using anti-annexin V antibodies and with electron microscopy. ANMB-MACS removes spermatozoa with PS-bound annexin V and produces a higher quality spermatozoal fraction. Spermatozoa with a deteriorated membrane are characterized by an increase in aCPs. A higher percentage of spermatozoa with ANMBs bound to PS and with aCPs were found in infertile patients. 相似文献
46.
Fritsche L Budde K Glander P Einecke G Diekmann F Schötschel R Neumayer HH 《International journal of clinical pharmacology and therapeutics》2003,41(10):488-491
The advent of new antidiabetic drugs is of special importance for diabetic patients with already impaired renal function since renal insufficiency is a relative or absolute contraindication for several of the established hypoglycemic drugs. Pioglitazone is a novel oral hypoglycemic agent that increases insulin responsiveness in target tissues. Pioglitazone and its active metabolites are excreted mainly via the liver. Drug exposure remains almost constant across a wide range of renal function since there is no accumulation of the drug or its active metabolites during repeated dosing in renal insufficiency. The pharmacokinetic properties of pioglitazone are ideally suited for patients with renal insufficiency. Although there are possible side effects (mainly fluid retention and weight gain and--very rarely--hepatotoxicity). Pioglitazone has a good safety profile in diabetic patients with impaired renal function. 相似文献
47.
48.
49.
虚拟现实技术在运动康复中的应用 总被引:1,自引:3,他引:1
目的:介绍虚拟现实技术在运动功能障碍的康复性训练领域的应用和新发展,讨论虚拟现实技术应用于运动康复的优势和前景。资料来源:应用计算机检索外文期刊PsycINFO和PubMed数据库1996/2006与虚拟现实技术在康复训练中应用相关的文章,检索语种为“English”,检索词为“motor rehabilitation,virtual reality”。检索中文期刊CNKI数据库1996/2006相关的文献,检索语种为中文,检索词为“康复,虚拟现实”。资料选择:根据摘要和关键词对资料进行初选,选择全面介绍虚拟现实技术的文章,以及近几年将虚拟现实技术应用于空间感知障碍和运动功能受损患者康复训练的实验研究报告。资料提炼:在上述3个数据库中分别检索到相关英文文献121篇,以及中文文献21篇,按上述标准纳入18篇,再继续搜索已有文献引用和被引用的参考文献,最后得到相关的中英文文献30篇。资料综合:30篇文献中,4篇文章详细介绍了虚拟现实技术在运动康复领域的应用,26篇实验报告了应用虚拟现实对受损的运动功能进行康复性训练的成效。按照运动康复的种类将研究报告分为4类:平衡和姿态训练、行走训练、上下肢康复训练和日常生活技能训练。通过模仿练习,感知运动受损的患者可以在虚拟环境中完成针对性训练任务,学会运动技能。在虚拟环境中习得的运动技能可以迁移到现实世界的真实任务中。结论:与传统康复训练方法相比,虚拟现实具有更安全、更有趣、针对性强、康复速度快、疗效好等优势。作为一种有效的运动康复技术手段,虚拟现实技术有很好的发展前景。 相似文献
50.
Platelet adhesion and thrombus formation on subendothelium in platelets deficient in glycoproteins IIb-IIIa, Ib, and storage granules 总被引:22,自引:1,他引:22
Patients whose platelets are deficient in glycoprotein (GP) Ib, IIb- IIIa (thrombasthenia), or granule substances (storage pool deficiency, SPD) were studied to define further the properties of platelets that mediate platelet adhesion and thrombus formation on subendothelium. Both nonanticoagulated and citrated blood were exposed to everted, de- endothelialized rabbit vessel segments under controlled flow conditions and shear rates varying from 650 to 3,300 sec-1. Morphometry was used to measure platelet thrombus dimensions and the percentage of the subendothelial surface covered with contact (C) or spread (S) platelets. Adhesion was defined as C + S. The results in SPD demonstrated (1) reduced thrombus dimensions in delta-SPD (pure dense granule deficiency) in proportion to the magnitude of the dense granule defect; (2) an even greater reduction in thrombus dimensions in patients with combined deficiencies of alpha and dense granules (alpha delta-SPD); and (3) impaired platelet adhesion at several conditions in alpha delta-SPD and, in delta-SPD, a hematocrit-dependent impairment of adhesion in citrated blood at 2,600 sec-1. In thrombasthenia, platelets were present as a monolayer on the subendothelial surface in both nonanticoagulated and citrated blood, indicating an absolute requirement for GPIIb-IIIa in promoting platelet-platelet interaction at all shear rates and perfusion times. Two types of abnormalities in platelet-vessel wall interactions were observed. In nonanticoagulated blood, the percentage of platelets in the C phase was consistently increased at all shear rates, but C + S values were normal. These observations indicate that platelets deficient in GPIIb-IIIa do not spread normally on the subendothelial surface exposed to nonanticoagulated blood. With citrated blood, the C + S value in thrombasthenia was reduced at both 800 and 2,600 sec-1, as in von Willebrand's disease, and a similar degree of reduction (about 50%) was observed in normal blood treated with a monoclonal antibody to GPIIb- IIIa. The findings, together with theoretical considerations, are consistent with an hypothesis that GPIIb-IIIa mediates the spreading of platelets on subendothelium following the initial attachment through GPIb and that GPIIb-IIIa may be considered an adhesion site on the platelet membrane. Abnormalities of GPIIb-IIIa may, depending on the conditions of study, result in either increased values of C platelets or decreased values of C + S. The results of the study further suggest that a complex interaction of platelet granule factors and membrane GP mediate platelet adhesion and thrombus formation. 相似文献