全文获取类型
收费全文 | 16787篇 |
免费 | 1506篇 |
国内免费 | 1273篇 |
专业分类
耳鼻咽喉 | 162篇 |
儿科学 | 189篇 |
妇产科学 | 142篇 |
基础医学 | 2199篇 |
口腔科学 | 260篇 |
临床医学 | 2169篇 |
内科学 | 2559篇 |
皮肤病学 | 123篇 |
神经病学 | 1005篇 |
特种医学 | 584篇 |
外国民族医学 | 19篇 |
外科学 | 1784篇 |
综合类 | 2738篇 |
现状与发展 | 2篇 |
一般理论 | 2篇 |
预防医学 | 1179篇 |
眼科学 | 532篇 |
药学 | 1634篇 |
22篇 | |
中国医学 | 788篇 |
肿瘤学 | 1474篇 |
出版年
2024年 | 55篇 |
2023年 | 287篇 |
2022年 | 633篇 |
2021年 | 900篇 |
2020年 | 653篇 |
2019年 | 546篇 |
2018年 | 579篇 |
2017年 | 546篇 |
2016年 | 502篇 |
2015年 | 817篇 |
2014年 | 887篇 |
2013年 | 816篇 |
2012年 | 1188篇 |
2011年 | 1342篇 |
2010年 | 782篇 |
2009年 | 668篇 |
2008年 | 920篇 |
2007年 | 937篇 |
2006年 | 855篇 |
2005年 | 957篇 |
2004年 | 578篇 |
2003年 | 520篇 |
2002年 | 462篇 |
2001年 | 363篇 |
2000年 | 433篇 |
1999年 | 418篇 |
1998年 | 291篇 |
1997年 | 244篇 |
1996年 | 183篇 |
1995年 | 184篇 |
1994年 | 160篇 |
1993年 | 135篇 |
1992年 | 124篇 |
1991年 | 124篇 |
1990年 | 92篇 |
1989年 | 85篇 |
1988年 | 66篇 |
1987年 | 66篇 |
1986年 | 51篇 |
1985年 | 42篇 |
1984年 | 15篇 |
1983年 | 16篇 |
1982年 | 9篇 |
1981年 | 8篇 |
1980年 | 3篇 |
1979年 | 9篇 |
1974年 | 2篇 |
1973年 | 4篇 |
1972年 | 2篇 |
1965年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
Role of endothelin in the pathogenesis of hypertension in spontaneously hypertensive and 2 kidneys 1 clip rats. 总被引:1,自引:0,他引:1
The plasma endothelin (ET) level in spontaneously hypertensive rats (SHR) and 2K1C hypertension animal models and its vasoconstrictive effect on renal and tail arteries were studied. The results demonstrated that there was no difference in plasma ET level between the hypertensive groups SHR, 2K1C, normotensive control groups Wistar Kyot (WKY) and Sprague Dawley (SD), while the vasoconstrictive effect of ET in SHR was more dominant than in WKY. The EC50 of the renal and tail arteries in SHR (0.8912 +/- 0.1662 x 10(-8) M, 0.6103 +/- 0.0878 x 10(-8) M) was apparently lower than that in WKY (1.77 +/- 0.2991 x 10(-8) M, 1.2267 +/- 0.2502 x 10(-8) M, P less than 0.05), but no difference was found in 2K1C and SD rats. The four groups of animals exhibited no difference of such effects as response to norepine-phrine (NA). The findings suggested that the increased arteriole sensitivity to ET be an important factor in the pathogenesis of hypertension in SHR.
相似文献
32.
33.
The platelet interactivity phenotype of Streptococcus sanguis influences the course of experimental endocarditis. 下载免费PDF全文
M C Herzberg G D MacFarlane K Gong N N Armstrong A R Witt P R Erickson M W Meyer 《Infection and immunity》1992,60(11):4809-4818
A strain of Streptococcus sanguis that induced rabbit platelets to aggregate in vitro (Agg+ phenotype) was hypothesized to be a more virulent pathogen than an Agg- strain in experimental endocarditis in rabbits. A left ventricular catheter was implanted, and then an Agg+ or Agg- strain was inoculated intravenously. Vegetations formed on the aortic semilunar valves but were unaffected by the duration of implantation of the catheter. Vegetations enlarged by accumulating platelets and their mass increased directly with the duration of endocarditis. Inoculation of the Agg+ strain consistently caused endocarditis with significantly larger vegetations, a more severe clinical course (including febrile episodes, hematological changes, and signs of myocardial ischemia), more gross lesions in major organs, and greater mortality than inoculation with the Agg- strain, saline, or the Agg+ strain pretreated with monospecific rabbit immunoglobulin G or Fab fragments against its platelet aggregation-associated protein (PAAP; class II). In experimental endocarditis, PAAP expressed by Agg+ S. sanguis appeared to be an important virulence factor. 相似文献
34.
经内镜胆管引流术在肝门部恶性胆管梗阻中的应用及其评价 总被引:9,自引:2,他引:7
肝门部恶性肿瘤手术切除率极低,临床处理十分棘手。作者采用内镜胆管引流术治疗此类肿瘤288例次(肝门部胆管癌184例、胆囊癌23例、肝细胞癌侵犯肝门部胆管47例、其他转移性肿瘤34例),其中行内镜鼻胆管引流162例次、塑料内置管引流80例次、放置可膨式金属胆道支架46例、4例患者接受同期双内置管引流。引流总有效率为67.0%,其中效果满意者43.1%;40例患者术后1个月内发生胆管炎,发生率为13.8%,3例死亡;长期随访病例的平均存活期5.3个月。我们观察到治疗的效果与Bismuth分型有密切关系,如果全肝40%以上的胆系得到引流,黄疸有望消退;左、右两侧胆管同时引流可扩大引流范围,提高疗效;应合理选择三种内镜胆管引流方法并适时灵活转换才能获得满意的疗效。结论:对于肝门部肿瘤,内镜胆管引流术是一种安全有效的治疗手段,可作为首选的姑息性治疗。 相似文献
35.
96名镍作业工人测定结果:非特异酯酶阳性细胞百分率(ANAE+%)为76.8%±8.0%,T细胞亚群CD2、CD4、CD8阳性细胞百分率(CD+2%、CD+4%、CD+8%)及CD+4/CD+8比值分别为65.6%±10.5%、56.3%±12.1%、34.3%±8.2%和1.76±0.6;酵母多糖刺激的外周血多形核白细胞化学发光(PMN-CL)本底和峰值分别为48±23和3073±684CPS/106PMN;血清硒和丙二醛含量分别为1.22±0.23和4.76±0.88μmol/L。与非镍作业的地区对照组比较,T细胞CD+8%增高,CD+4/CD+8比值下降,化学发光的本底值降低,峰值增加,血清Se含量下降,丙二醛含量升高。分析镍作业工人工龄与后三项指标变化的关系,工龄大于20年与小于10年有统计学上明显差别。这些观察指标为镍作业人员医学观察增加新的监护指标提供依据。 相似文献
36.
J. Gong B. D. Rawal C. F. Högman MD G. N. Vyas B. Nilsson and I. Gustafsson 《Vox sanguinis》1994,66(3):166-170
We report studies on the complement sensitivity of four strains of Yersinia enterocolitica , serotypes O:3, O:9, O:5,27, and O:20, isolated from blood units involved in transfusion fatalities. Complement in fresh CPD plasma killed Y. enterocolitica within 4 h at 22°C in 100% of the experiments. The bactericidal action was serotype and complement activation pathway dependent. Both classic and alternate pathways seemed to be active, but the latter to a lesser degree. When the classic pathway was blocked by chelation of Ca2+ no complete killing was obtained. Complement did not enhance or condition Yersinia for leucocyte filter retention. Direct removal of Yersinia by filtration was also related to serotype; all strains were reduced by filtration in heat-inactivated plasma, and all except serotype O:5,27 were reduced in Ca2+ -chelated plasma. Our findings may explain why plasma products and platelet concentrates are rarely involved in Yersinia sepsis related to transfusion. 相似文献
37.
Heme inhibits human immunodeficiency virus 1 replication in cell cultures and enhances the antiviral effect of zidovudine. 总被引:3,自引:0,他引:3 下载免费PDF全文
38.
39.
40.
龚燕平 《世界急危重病医学杂志》2005,2(6):995-995
一位有酒精依赖病史的61岁老年女性因酒精中毒被送到急诊科,其血浆酒精浓度为322mg/dl。她承认因为发胶中非自然的的酒精成分,她混水应用了一瓶14盎司的发胶。最初她在参加一次酒精匿名会议时学会了这种应用非饮料酒精的方法,为了向家人隐瞒滥用酒精的事实,她开始应用并持续了数年。她应用的发胶的非自然酒精含量高达50%.其吸收量约为7盎司酒精,相当于141.25盎司80标准强度的酒精饮料。 相似文献