全文获取类型
收费全文 | 815篇 |
免费 | 88篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 18篇 |
儿科学 | 31篇 |
妇产科学 | 7篇 |
基础医学 | 95篇 |
口腔科学 | 4篇 |
临床医学 | 96篇 |
内科学 | 276篇 |
皮肤病学 | 21篇 |
神经病学 | 25篇 |
特种医学 | 64篇 |
外科学 | 116篇 |
综合类 | 31篇 |
预防医学 | 74篇 |
眼科学 | 5篇 |
药学 | 37篇 |
肿瘤学 | 27篇 |
出版年
2022年 | 3篇 |
2021年 | 6篇 |
2020年 | 5篇 |
2019年 | 7篇 |
2018年 | 11篇 |
2017年 | 5篇 |
2016年 | 9篇 |
2015年 | 13篇 |
2014年 | 16篇 |
2013年 | 31篇 |
2012年 | 34篇 |
2011年 | 24篇 |
2010年 | 25篇 |
2009年 | 33篇 |
2008年 | 26篇 |
2007年 | 45篇 |
2006年 | 26篇 |
2005年 | 21篇 |
2004年 | 20篇 |
2003年 | 26篇 |
2002年 | 20篇 |
2001年 | 31篇 |
2000年 | 26篇 |
1999年 | 30篇 |
1998年 | 24篇 |
1997年 | 19篇 |
1996年 | 28篇 |
1995年 | 22篇 |
1994年 | 29篇 |
1993年 | 25篇 |
1992年 | 19篇 |
1991年 | 20篇 |
1990年 | 21篇 |
1989年 | 30篇 |
1988年 | 16篇 |
1987年 | 23篇 |
1986年 | 22篇 |
1985年 | 23篇 |
1984年 | 20篇 |
1983年 | 8篇 |
1982年 | 9篇 |
1981年 | 13篇 |
1980年 | 8篇 |
1979年 | 3篇 |
1977年 | 6篇 |
1975年 | 5篇 |
1960年 | 3篇 |
1907年 | 3篇 |
1899年 | 2篇 |
1890年 | 2篇 |
排序方式: 共有927条查询结果,搜索用时 648 毫秒
71.
Ohne ZusammenfassungHiezu Taf. XXIII. 相似文献
72.
73.
Dr. J. Neuberger 《Naunyn-Schmiedeberg's archives of pharmacology》1890,27(1-2):39-49
Ohne Zusammenfassung 相似文献
74.
Proliferation and differentiation of a transfected Schwann cell line is altered by an artificial basement membrane 总被引:1,自引:0,他引:1
Rapidly dividing transfected Schwann cells were grown on Matrigel, a reconstituted basement membrane gel. Matrigel decreased the proliferation of the cells by 75% when compared to sister cultures that were grown on an untreated plastic substrate. Some transfected cells plated onto a Matrigel substrate formed colonies similar to that observed when the cells were plated on a plastic substrate. Additionally, many cells on Matrigel assembled themselves into fascicles projecting away from the colonies. These fascicles were composed of transfected Schwann cells that had assumed a bipolar appearance reminiscent of quiescent secondary Schwann cells in culture. Transfected cells grown on Matrigel contained approximately 10-fold less glial fibrillary acidic protein when compared to sister cultures grown on an untreated plastic substrate. By indirect immunofluorescence laminin immunoreactivity appeared as globules within the cytoplasm of the cells which were cultured on a plastic substrate. However, cells that were grown on the Matrigel substrate appear to organize laminin in a linear array around themselves. These results demonstrate that the presence of an artificial basement membrane alters the morphology, rate of proliferation, and state of differentiation of a transfected Schwann cell line. 相似文献
75.
76.
SUMMARY We report an unusual case of a pharyngeal diverticulum arising as a result of extrusion of a bone graft inserted during anterior cervical fusion operation. The dense scar tissue at the site of extrusion of the bone graft probably caused traction on the posterior pharyngeal wall, with the development of a pharyngeal pouch. This is believed to be the first case with acquired pharyngeal diverticulum following anterior cervical fusion to be recorded in the literature. 相似文献
77.
汉语阅读障碍儿童在本顿视觉保持测验中的反应特征 总被引:1,自引:0,他引:1
目的:比较阅读障碍儿童与正常儿童在本顿视觉保持测验中的反应特征,探索阅读障碍儿童视觉空间记忆能力的特点。方法:①2005-07/2006-05在儿童发育行为门诊遴选阅读障碍儿童20名(平均年龄10.2岁),按1∶1配对原则,选择年龄、性别、年级和家庭状况等条件与阅读障碍组相似的20名正常阅读能力儿童为对照组(平均年龄10.1岁)。②应用国内修订版本顿视觉保持测验C式B法,D式C法和E式D法对两组儿童进行个别测试。C式图卡呈现5s后让被试默画(视觉记忆能力),D式图卡让被试临摹(视觉结构能力),E式图卡呈现10s后间隔15s再让被试默画(视觉延迟记忆能力)。③对两组儿童的视觉记忆保持能力、视觉结构能力和延迟记忆能力进行测试,分别记录两组儿童测验的正确分(每一图卡根据全或无的原则记1或0分,总分0~10)及错误次数(错误类型分为遗漏或增加、变形、持续、旋转、位置错误和大小错误6个范畴),进行配对t检验。结果:40名受试者均进入结果分析。①正确得分:在视觉记忆和视觉结构能力测验中阅读障碍组低于对照组(5.00±2.45,6.60±1.82,P=0.019;7.50±2.44,8.95±1.32,P=0.015),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.077)。②总错误分:在视觉记忆和视觉结构能力测验中阅读障碍组高于对照组(7.65±4.20,4.90±3.24,P=0.016;3.20±3.93,1.15±1.46,P=0.035),在视觉延迟记忆测试中,两组得分比较差异不显著(P=0.389)。③错误类型:阅读障碍组儿童在视觉记忆能力测试中变形和持续性错误次数均显著多于对照组(3.95±2.40,1.75±1.52;0.35±0.67,0;P均<0.05),在视觉结构能力测试中变形错误次数显著多于对照组(1.35±1.69,0.35±0.75,P<0.05)。结论:阅读障碍儿童的视觉空间短时记忆能力、视觉结构和视觉运动整合能力存在缺陷。 相似文献
78.
79.
80.
J G Kenna J Neuberger R Williams 《The Journal of pharmacology and experimental therapeutics》1987,242(2):733-740
Previous studies have demonstrated that sera from patients with severe liver damage after halothane anesthesia ("halothane hepatitis") contain antibodies reacting with novel antigenic determinants expressed on hepatocytes from rabbits exposed previously to halothane. To determine the structure of the halothane-induced antigen(s), immunoblotting experiments were performed using patient sera and rabbit liver subcellular fractions. Three polypeptide antigens (Mr 100,000, 76,000 and 57,000) expressed in liver fractions from animals sacrificed 16 hr after exposure to 1% halothane in oxygen for 45 min, but not in fractions from unexposed animals, were identified. Analysis of fractions prepared by differential and sucrose density gradient centrifugation, and characterized by enzyme marker analysis, localized all three antigens to a microsomal subfraction relatively enriched in glucose-6-phosphatase activity, therefore, presumably derived from the endoplasmic reticulum. Antibodies to these antigens were detected in 19 of 24 sera from patients with halothane hepatitis, and four distinct patterns of antibody specificity were observed: 100,000 + 76,000 (seven patients), 100,000 alone (seven patients), 76,000 alone (three patients) and 57,000 alone (two patients). Such antibodies were not detectable in sera from 24 normal blood donors or 36 control patients. Thus, halothane induces expression of three distinct polypeptide antigens in liver, and patients with halothane hepatitis differ in patterns of recognition of these antigens by circulating antibodies. 相似文献