首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   102432篇
  免费   10911篇
  国内免费   6795篇
耳鼻咽喉   1132篇
儿科学   1434篇
妇产科学   919篇
基础医学   7976篇
口腔科学   2123篇
临床医学   12319篇
内科学   10635篇
皮肤病学   1079篇
神经病学   3195篇
特种医学   4040篇
外国民族医学   20篇
外科学   9547篇
综合类   25282篇
现状与发展   27篇
一般理论   2篇
预防医学   10185篇
眼科学   1800篇
药学   12657篇
  176篇
中国医学   9183篇
肿瘤学   6407篇
  2024年   594篇
  2023年   1715篇
  2022年   4183篇
  2021年   5235篇
  2020年   4258篇
  2019年   2757篇
  2018年   2912篇
  2017年   3287篇
  2016年   2776篇
  2015年   4611篇
  2014年   5786篇
  2013年   6530篇
  2012年   9257篇
  2011年   9475篇
  2010年   7958篇
  2009年   6849篇
  2008年   7344篇
  2007年   7133篇
  2006年   6355篇
  2005年   4989篇
  2004年   3714篇
  2003年   3219篇
  2002年   2697篇
  2001年   2095篇
  2000年   1527篇
  1999年   804篇
  1998年   378篇
  1997年   344篇
  1996年   261篇
  1995年   207篇
  1994年   211篇
  1993年   134篇
  1992年   101篇
  1991年   84篇
  1990年   92篇
  1989年   62篇
  1988年   47篇
  1987年   42篇
  1986年   38篇
  1985年   19篇
  1984年   22篇
  1983年   14篇
  1982年   3篇
  1981年   3篇
  1980年   2篇
  1972年   1篇
  1959年   2篇
  1957年   3篇
  1956年   5篇
  1955年   2篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
目的对不同季铵化程度(DQ)的N-三甲基壳聚糖(TMC)促进阿昔洛韦(ACV)滴眼液眼部滞留性进行考察。方法将浓度为0.5%,DQ分别为20%、40%及60%的TMC(TMC20,TMC40,TMC60)加入ACV滴眼液中;以同浓度壳聚糖(CS)ACV滴眼液为阳性对照,以普通ACV滴眼液为阴性对照,选用家兔为实验动物,采用悬挂泡技术和束缚泡技术进行离体眼球表面接触角及解吸附动力学进行研究,同时在各种ACV滴眼液中分别加入0.05%的荧光素钠为示踪剂,在体研究各种ACV滴眼液在家兔眼部的滞留性。结果与普通ACV滴眼液相比,含CS及TMC的滴眼液在角膜表面的接触角明显降低,解吸时间及在体滞留时间明显延长(P<0.05);与同浓度的CS ACV阳性对照相比,TMC20促进滞留作用较弱,而TMC40作用差异无显著性(P>0.05),而TMC60的作用明显较强(P<0.05)结论 TMC可显著增加ACV的眼部滞留性,且与其DQ呈正相关。  相似文献   
2.
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019  相似文献   
3.
随着整体理论、吊床理论及肛提肌维持盆底器官的重要性等多种观点的提出,盆底器官脱垂(POP)发病机制复杂临床表现多样化,因此获得POP的完整信息,应结合临床检查及辅助检查手段,在辅助检查手段中应用最广泛、最有优势的影像学技术。多种影像学技术应用于盆底,包括静态及动态盆底影像学技术,帮助临床医师全面了解POP的发病机制、诊断并建立盆底治疗方案及完善的术后随访体系。  相似文献   
4.
Objective To investigate effect of reduced glutathione and diammonium glycyrrhizinate on the treatment of hepatic damage in experimental dogs following open abdominal injuries coupled with seawater immersion. Methods Twenty-four dogs with open abdominal injuries were randomly divided into 3 groups: the control group (given with simple observation after 1.5 h seawater immersion); the routine treatment group (given routine care and fluid transfusion after 1.5 h seawater immersion) ; the hepatic treatment group (given routine are, fluid transfusion and hepatic treatment as well, after 1.5 h seawater immersion). Each group consisted of 8 dogs. Blood samples were taken at different time points to measure total bilirubin (TB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), prothromin time (PT), endotoxin, tumor necrosis factor-α(TNF-α), interleukin-6 (IL-6), and pathological examination was also made at the same time. Results For the control group, contents of TB, ALT, AST and LDH increased significantly and survival time was less than 24 hours. Contents of TB, ALT, AST and LDH of the routine treatment group also increased significantly, but survival time of all the experimental animals was mere than 24 hours. Reduced glutathione and diammonium glycyrrhizinate could reduce the extent of lesion quite significantly 12~24 hours following open abdominal injuries. Conclusions Reduced glutathione and diammonium glycyrrhizinate seemed to have good effects on the treatment and prevention against hepatic damage induced by trauma coupled with seawater immersion. It could be used as a primary means for the treatment of such kind of hepatic damage.  相似文献   
5.
Signaling of RANK (receptor activator of nuclear factor kappa B) through its ligand RANKL appears critical in osteolysis associated with aseptic loosening (AL). The purpose of this study was to investigate the role of RANK in a murine osteolysis model developed in RANK knockout (RANK(-/-)) mice. Ultra high molecular weight polyethylene (UHMWPE) debris was introduced into established air pouches on RANK(-/-) mice, followed by implantation of calvaria bone from syngeneic littermates. Wild type C57BL/6 (RANK(+/+)) mice injected with either UHMWPE or saline alone were included in this study. Pouch tissues were collected 14 days after UHMWPE inoculation for molecular and histology analysis. Results showed that UHMWPE stimulation induced strong pouch tissue inflammation in RANK(-/-) mice, as manifested by inflammatory cellular infiltration, pouch tissue proliferation, and increased gene expression of IL-1beta, TNFalpha, and RANKL. However, the UHMWPE-induced inflammation in RANK(-/-) mice was not associated with the osteoclastic bone resorption observed in RANK(+/+) mice. In RANK(+/+) mice subjected to UHMWPE stimulation, a large number of TRAP(+) cells were found on the implanted bone surface, where active osteoclastic bone resorption was observed. No TRAP(+) cells were found in UHMWPE-containing pouch tissues of RANK(-/-) mice. Consistent with the lack of osteoclastic activity shown by TRAP staining, no significant UHMWPE particle-induced bone resorption was found in RANK(-/-) mice. A well preserved bone collagen content (Van Gieson staining) and normal plateau surface contour [microcomputed tomography (microCT)] of implanted bone was observed in RANK(-/-) mice subjected to UHMWPE stimulation. In conclusion, this study provides the evidence that UHMWPE particles induce strong inflammatory responses, but not associated with osteoclastic bone resorption in RANK(-/-) mice. This indicates that RANK signaling is essential for UHMWPE particle-induced osteoclastic bone resorption, but does not participate in UHMWPE particle-induced inflammatory response.  相似文献   
6.
北欧清洗消毒现状——消毒过程如何减少医院感染   总被引:1,自引:0,他引:1  
宋慧 《中华护理杂志》2006,41(12):1148-1149
1“消毒”定义的发展250多年前,在瑞典的医疗工作中已经开始使用“消毒”(Disinfection)作为术语,主要指控制或减少医院内的怪味。当时微生物致病的重要性依然不为民众所知。消毒的现代定义是指去除或杀灭致病微生物,以达到清洁要求。消毒的理想方式是完全去除表面的微生物,当然如果真能做到这一点,物品的表面就不止达到了消毒要求,而应为无菌状态了。2现代消毒技术水作为溶剂和优良的载体,对清洁过程起着至关重要的作用。但是,单纯用水或水溶液清洗的方法达不到去除所有微生物的要求。这样,消毒过程要分两步,第1步是通过清洗或机械手段尽…  相似文献   
7.
目的探讨一种新型简易防脱出的义眼台的制作方法与效果。方法根据眼球摘除后的解剖特点设计义眼台大小,选择聚甲基丙烯酸甲酯和涤纶布为材料制作复合材料义眼台,并对6只家兔行眼球摘除后置入义眼台,经HE染色观察及肉眼观察术后不同时间置入物与眼周围组织的解剖关系。结果聚甲基丙烯酸甲酯部分与组织无黏连,涤纶布形成牢固黏连,周围有纤维组织长入并包绕,义眼台无脱出、移位。结论以聚甲基丙烯酸甲酯和涤纶布为材料制作复合义眼台,方法简易,效果可靠,组织相容性好,术后反应轻,值得在临床上推广使用。  相似文献   
8.
三磷酸腺苷结合盒运转体A1与颈动脉粥样硬化斑块的关系   总被引:4,自引:0,他引:4  
目的 探讨三磷酸腺苷结合盒运转体A1(ATP binding cassette transporter A1,ABCA1)在人颈动脉粥样硬化斑块中的表达变化及作用机制.方法 收集24例人颈动脉粥样硬化斑块标本和10例肠系膜动脉标本(对照组),采用RT-PCR测定ABCA1 mRNA和视黄酸X受体α(RXRα)mRNA表达水平,并采用Western Blot检测ABCA1及RXRα的蛋白表达水平.24例人颈动脉粥样硬化斑块标本按病理分级,比较病理组织为Ⅲ级和Ⅰ级动脉粥样硬化组织间ABCA1 mRNA、RXRαmRNA表达水平及蛋白表达水平.结果 颈动脉粥样硬化斑块组的ABCA1 mRNA(0.79±0.04)和RXRα mRNA(0.73±0.04)表达与对照组相比上调,差异有统计学意义(P<0.05);ABCA1 mRNA与RXRα mRNA增加水平相关(P<0.05);颈动脉粥样硬化斑块的ABCA1蛋白表达(0.22±0.03)下调水平与对照组(0.53±0.03)相比差异有统计学意义(P<0.05);Ⅲ级和Ⅰ级动脉硬化斑块ABCA1mRNA、RXRα mRNA及蛋白表达水平差异有统计学意义(P<0.05).结论 ABCA1及RXRα蛋白表达水平下调可能是进展性动脉粥样硬化损害的关键因素.  相似文献   
9.
在颈椎前路减压、植骨、带锁钢板内固定技术日渐成熟的今天,越来越多的医院开展了该项手术。自1998年2月-2005年8月应用该方法治疗颈椎病215例,发生与内置物钢板及钛网相关的并发症14例,为此积累了一定的经验,现总结如下。1临床资料本组215例,男126例,女89例;年龄42~82岁,平均  相似文献   
10.
目的:直肠腺瘤和其他疑似为良性的病变应用经肛门内镜切除术并未普及。该项研究旨在评估经肛门内镜切除术的效能和安全性。方法:回顾性研究分析在1993-2004年之间3所斯德哥尔摩医院中经肛门内镜切除术的患,内容包括患自身及病变特性、并发症、随访时间和复发率。结果:180例中共131例行经肛门内镜切除术。160例经组织学诊断为腺瘤,12例为癌瘤,其余8例分别为增生、纤维化或正常黏膜。直肠腺瘤患中,77例仅行单次经肛门内镜切除术,16例因巨大腺瘤而多次行该手术,27例因复发而需另行经肛门内镜切除术或其他手术。中位复发时间为7个月,但未出现直肠癌。16例手术患出现并发症。2例患必须行Hartman手术,1例因肠穿孔,另1例因出血。手术期间无死亡。未复发的中位随访期为32个月(极差0—67)。[编按]  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号