全文获取类型
收费全文 | 19375篇 |
免费 | 2128篇 |
国内免费 | 1639篇 |
专业分类
耳鼻咽喉 | 94篇 |
儿科学 | 244篇 |
妇产科学 | 151篇 |
基础医学 | 1902篇 |
口腔科学 | 360篇 |
临床医学 | 2458篇 |
内科学 | 2631篇 |
皮肤病学 | 220篇 |
神经病学 | 1071篇 |
特种医学 | 944篇 |
外国民族医学 | 6篇 |
外科学 | 2276篇 |
综合类 | 3779篇 |
现状与发展 | 2篇 |
一般理论 | 1篇 |
预防医学 | 1449篇 |
眼科学 | 515篇 |
药学 | 2139篇 |
11篇 | |
中国医学 | 1434篇 |
肿瘤学 | 1455篇 |
出版年
2024年 | 70篇 |
2023年 | 307篇 |
2022年 | 724篇 |
2021年 | 829篇 |
2020年 | 719篇 |
2019年 | 685篇 |
2018年 | 651篇 |
2017年 | 622篇 |
2016年 | 654篇 |
2015年 | 917篇 |
2014年 | 1105篇 |
2013年 | 1109篇 |
2012年 | 1479篇 |
2011年 | 1653篇 |
2010年 | 1175篇 |
2009年 | 1023篇 |
2008年 | 1155篇 |
2007年 | 1183篇 |
2006年 | 970篇 |
2005年 | 855篇 |
2004年 | 789篇 |
2003年 | 877篇 |
2002年 | 822篇 |
2001年 | 629篇 |
2000年 | 478篇 |
1999年 | 351篇 |
1998年 | 223篇 |
1997年 | 183篇 |
1996年 | 156篇 |
1995年 | 120篇 |
1994年 | 101篇 |
1993年 | 84篇 |
1992年 | 79篇 |
1991年 | 71篇 |
1990年 | 65篇 |
1989年 | 47篇 |
1988年 | 45篇 |
1987年 | 39篇 |
1986年 | 30篇 |
1985年 | 21篇 |
1984年 | 16篇 |
1983年 | 6篇 |
1982年 | 6篇 |
1979年 | 6篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1932年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
高频超声检测颈动脉内膜-中层厚度及外周血管内皮功能评价动脉粥样硬化 总被引:1,自引:0,他引:1
目的 探讨高频超声检测颈动脉内膜-中层厚度与肱动脉内皮依赖性舒张功能在动脉粥样硬化中的诊断价值.方法 冠状动脉造影的老年患者69例及青年志愿者20例,分别行颈动脉超声检查,同时采用充气加压法测定肱动脉血流介导的内径扩张值,超声测值与冠脉造影结果对照分析.结果 ①颈动脉内膜-中层厚度值随粥样硬化斑块的增多、冠脉狭窄程度的加重而增高;②动脉粥样硬化患者在内膜-中层厚度值增高之前即可出现内皮功能损伤,肱动脉内径扩张值降低早于内膜-中层厚度值增高之前出现,内径扩张值随冠脉狭窄程度加重而下降.结论 高频超声检测颈动脉内膜-中层厚度、内径扩张值诊断早期动脉粥样硬化敏感性高,并且有助于对冠脉狭窄程度作出判断. 相似文献
22.
进一步重视脂肪新功能对创面愈合作用的研究 总被引:9,自引:1,他引:8
创面愈合的研究范围正随着相关领域的研究进展而不断拓展和完善。以皮下脂肪组织为例 ,以往多数的研究认为 ,脂肪组织来源于间充质细胞 (mesenchymalcell,MC) ,其功能仅是一个能量贮存仓库。但近年来的研究表明 ,脂肪组织还可能是一个重要的内分泌器官 ,在发育学、信号转导 ,以及干细胞作用等多方面与组织修复存在着密切联系。有专家认为 ,加强对脂肪细胞新功能的研究和开发 ,有可能对创面修复和组织再生机制产生新的认识 ,并寻找出新的促愈合手段。脂肪细胞参与创面愈合首先表现在它可能作为一个内分泌器官。迄今为止 ,已经发现人的脂肪细… 相似文献
23.
24.
25.
采用细胞内微电极记录技术,同步观察了3,6-[二甲氨基]-二苯并碘因甲酸盐(IHC-64)对豚鼠心乳头肌细胞动作电位和收缩力的作用。50μmol/L IHC-64抑制心肌收缩力,而不影响快反应动作电位。增加IHC-64浓度,动作电位0相最大峰值(APA)、除极速率(dp/dt_(max))和复极50%和90%时程(APD_(50)、APD_(90))被明显抑制。IHC-64抑制慢反应动作电位,提高细胞外钙浓度可拮抗这种抑制。结果提示,IHC-64主要抑制慢Ca~(2+)内流,同时也部分抑制快Na~+内流,它可能是一种新型B类钙通道阻滞剂。 相似文献
26.
出土文献与彭祖养生学术研究 总被引:1,自引:0,他引:1
彭祖是我国古代的"寿星",随着一系列的考古发现,如汉早期马王堆墓《十问》篇、张家山汉墓《引书》篇,尤其是上海博物馆藏竹简(三)有《彭祖》篇,改变了我们对彭祖学术的认识,不仅为证明楚国产生并流传黄老学派思想提供了佐证,而且在学术史领域提供了新的课题,进一步廓清了彭祖养生学术之源乃是古代巫术,其流是在春秋战国秦汉时期被诸子传诵,与道家等流派结合,具有神仙色彩,最终被汉末魏晋道家改造为神仙方术。 相似文献
27.
Longitudinal Analysis of Severe Acute Respiratory Syndrome (SARS) Coronavirus-Specific Antibody in SARS Patients
下载免费PDF全文
![点击此处可从《Clinical and Vaccine Immunology : CVI》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Shan-Chwen Chang Jann-Tay Wang Li-Min Huang Yee-Chun Chen Chi-Tai Fang Wang-Huei Sheng Jiun-Ling Wang Chong-Jen Yu Pan-Chyr Yang 《Clinical and Vaccine Immunology : CVI》2005,12(12):1455-1457
The serum antibodies to severe acute respiratory syndrome (SARS) coronavirus of 18 SARS patients were checked at 1 month and every 3 months after disease onset. All of them except one, who missed blood sampling at 1 month, tested positive for the immunoglobulin G (IgG) antibody at 1 month. Fifteen out of 17 tested positive for the IgM antibody at 1 month. The serum IgM antibody of most patients became undetectable within 6 months after the onset of SARS. The IgG antibody of all 17 patients, whose serum was checked 1 year after disease onset, remained positive. 相似文献
28.
Qingfeng Sheng Yurong Shi Qiang Li Jihui Hao Ruifang Niu Xiyin Wei Yi Yang Lin Zhang 《中国肿瘤临床(英文版)》2006,3(6):442-446
A poptosis, an evolutionarily conserved form of cell suicide, oc- curs in two physiological stages: commitment and execution.[1] It has been found that several Bcl-2 family proteins are located in the outer mitochondrial membrane, where they control relea… 相似文献
29.
In this study, an animal model of multiple system organ failure (MSOF) in rabbits, engendered by feeding E. coli prior to severe hemorrhagic shock, was used for the purpose of investigating 1) the relationship between lipopolysaccharide (LPS) and MSOF, and 2) the effectiveness of Re-LPS antiserum in preventing MSOF. The results showed that endotoxemia occurred very early, and its degree correlated well with that of organ dysfunction. Re-LPS antiserum administration abated the toxic effects and lowered the incidence of MSOF. These results suggest that sequential analysis of circulating LPS levels may be useful for the early diagnosis of MSOF, and that gut-derived endotoxin might play an important role in the pathogenesis of experimental MSOF. 相似文献
30.
Early multiple organ dysfunction syndrome appears to be facilitated with bacterial translocation in severely burn injury, yet the mechanisms of bacterial translocation remains in dispute. The aim of this study was to investigate the potential role of intestinal bifidobacteria in the pathogenesis of gut-derived bacteria/endotoxin translocation following burns and the effects of bifidobacterial supplement on gut barrier. Methods: Wistar rats were randomly divided into burn group (Burn, n=60),sham burn group (SB, n=10) in experiment Ⅰ , and burn + saline group (BS, n=30), burn + bifidobacteria group (BB, n=30), and sham-burn + saline group (SS, n= 10) in experiment Ⅱ. Animals in BB group were fed bifidobacterial preparation (5 × 109 CFU/ml) after burns, 1.5ml,twice daily. Animals in BS and SS were fed saline. Samples were taken on days 1, 3, and 5 in burn groups, and on day 3 in sham-burn groups. The incidence of bacteria/endotoxin translocation and counts of Bifidobacterium, Fungi and Escherichia coli in gut mucosa were determined with standard methods. The levels of sIgA in mucus of small intestine were measured by RIA. The positive sIgA expression in lamina propria and ileum mucosal injury was evaluated light microscopically by blinded examiners. Results: Our results showed that the incidence of bacterial translocation was increased after burns, which was accompanied by significant decrease in number of bifidobacteria but significant increase in E. coli and fungi in gut mucosa, and elevation of levels of plasma endotoxin and IL-6 (P<0. 001).The incidence of bacterial translocation was markedly reduced after 3- and 5-day supplementation of bifidobacteria compared with control group (P<0.05). The counts of mucosal bifidobacteria were increased by 4- to 40-fold,while E. coli and fungi were decreased by 2- to 30-fold and 10- to 150-fold, respectively, after bifidobacterial supplementation in contrast to control group. The damage of mucosa tended to be less pronounced after 3-day bifidobacteria-supplemented formula compared with control group [grade 2(0-6) vs. grade 4(3-6), P<0.05]. Moreover, the expression and release of sIgA was markedly augmented after 3-day bifidobacteria-supplementation formula and it returned to normal range on day 5. Conclusion: The decrease in counts and proportion of bifidobacteria in mucous membrane flora may play an important role in the development of bacteria/endotoxin translocation following thermal injury. The supplement of exogenous bifidobacteria could per se improve gut barriers, and attenuate bacteria/endotoxin translocation secondary to major burns. 相似文献