全文获取类型
收费全文 | 91528篇 |
免费 | 10029篇 |
国内免费 | 7017篇 |
专业分类
耳鼻咽喉 | 802篇 |
儿科学 | 1407篇 |
妇产科学 | 1022篇 |
基础医学 | 9222篇 |
口腔科学 | 1867篇 |
临床医学 | 12123篇 |
内科学 | 12128篇 |
皮肤病学 | 740篇 |
神经病学 | 3941篇 |
特种医学 | 3142篇 |
外国民族医学 | 43篇 |
外科学 | 8081篇 |
综合类 | 18972篇 |
现状与发展 | 29篇 |
一般理论 | 3篇 |
预防医学 | 7847篇 |
眼科学 | 2348篇 |
药学 | 10647篇 |
124篇 | |
中国医学 | 6731篇 |
肿瘤学 | 7355篇 |
出版年
2024年 | 475篇 |
2023年 | 1751篇 |
2022年 | 4438篇 |
2021年 | 5466篇 |
2020年 | 4357篇 |
2019年 | 3289篇 |
2018年 | 3318篇 |
2017年 | 3336篇 |
2016年 | 3019篇 |
2015年 | 4753篇 |
2014年 | 5527篇 |
2013年 | 5289篇 |
2012年 | 7620篇 |
2011年 | 7911篇 |
2010年 | 5561篇 |
2009年 | 4633篇 |
2008年 | 5127篇 |
2007年 | 4806篇 |
2006年 | 4560篇 |
2005年 | 4095篇 |
2004年 | 2786篇 |
2003年 | 2589篇 |
2002年 | 2115篇 |
2001年 | 1791篇 |
2000年 | 1667篇 |
1999年 | 1662篇 |
1998年 | 968篇 |
1997年 | 942篇 |
1996年 | 729篇 |
1995年 | 742篇 |
1994年 | 573篇 |
1993年 | 344篇 |
1992年 | 407篇 |
1991年 | 397篇 |
1990年 | 306篇 |
1989年 | 256篇 |
1988年 | 235篇 |
1987年 | 204篇 |
1986年 | 155篇 |
1985年 | 115篇 |
1984年 | 64篇 |
1983年 | 51篇 |
1982年 | 39篇 |
1981年 | 23篇 |
1980年 | 15篇 |
1979年 | 28篇 |
1978年 | 10篇 |
1972年 | 3篇 |
1970年 | 4篇 |
1966年 | 3篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
101.
外周血细胞DNA、RNA及血红蛋白同时提取法 总被引:1,自引:0,他引:1
采用淋巴细胞分离液分离外周血中的有核细胞。经细胞裂解液处理,上清提取RNA,沉淀提取DNA,用分离液分离所得红细胞沉淀制备血红蛋白溶液,经对抽提物质量进行评价,发现3种提取物质量均高,本法能从少量外周血中同时分离DNA、RNA及血红蛋白,高效易操作,值得推广。 相似文献
102.
103.
The extent and time course of depression of successive reflex responses recorded with intracellular microelectrodes from the circular smooth muscle of the guinea pig small intestine were determined. Two stimuli were used, distension and distortion of the mucosa by compression; these were applied either at the same or at different sites. Excitatory responses oral and inhibitory responses anal to the stimuli were recorded. Post-stimulus depression of both ascending excitatory and descending inhibitory reflexes occurred, but the extent of depression was slightly less for the descending inhibition. A conditioning distension lasting 9 s depressed the excitatory response to a test distension applied 2 s later at the same site by 90%. After 30 s the depression was 50% and test responses were normal if inter-stimulus intervals were increased to 2 min. Increasing the duration of the conditioning stimulus increased the depression. Post-stimulus depression was less for compression stimuli than for distension stimuli and prior mucosal compression had almost no effect on responses to subsequent distension. The post-stimulus depression was greater if conditioning and test stimuli were at the same rather than different sites. For different sites, conditioning stimuli at 15 mm from the recording site (near) depressed responses to stimuli at 30 mm (far) to a greater extent than far stimuli depressed responses to near stimuli. If the conditioning stimulus at 15 mm was maintained until after the far test stimulus was applied, depression of the test response did not occur. It is concluded that the major sites of post-stimulus depression are at the synapses between primary sensory neurons and the first interneurons of reflex pathways, and that post-stimulus depression also occurs at other places in the pathway, presumably at synapses between interneurons or between interneurons and motor neurons. 相似文献
104.
Ying Qian Pedram Hamrah Florence Boisgerault Satoru Yamagami Sudhir Vora Gilles Benichou M Reza Dana 《Journal of interferon & cytokine research》2002,22(12):1217-1225
This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts. 相似文献
105.
TuberculosisandSchistosomiasisarethemajorcontagiousdiseaseswhicharethemostdangeroustothepeople’shealth Inordertogetridofthem ,wemustlookforamoreusefulvaccine Bythetech niquesofmolecularbiology ,2 6 0 0 0DaGlutathionStransferase (GST) genewasclonedintotheE coli MycobacteriumtransferringandexpressionvectorpBCG 2 0 0 0totransformittoMycobacteriumsmeg matismc2 15 5 (MS)andBCGseparatelyinordertoconstructrMS Sj2 6GSTvaccineandrBCG Sj2 6GSTvaccine Inthisstudy ,theBALB/cmicewereimmu niz… 相似文献
106.
尼莫地平复方丹参注射液治疗新生儿缺氧缺血性脑病疗效观察 总被引:1,自引:0,他引:1
目的观察尼莫地平联合复方丹参注射液治疗新生儿缺氧缺血性脑病(HIE)的疗效.方法 128例HIE患儿随机分为复方丹参注射液组32例,尼莫地平组,尼莫地平加复方丹参注射液,与对照组.结果复方丹参注射液组、尼莫地平组、尼莫地平加复方丹参注射液治疗组总有效率分别为81.3%(26/32)、80.0%(24/30)、97.1%(34/35),对照组总有效率为51.6%(16/31),P<0.05.结论尼莫地平与复方丹参注射液在治疗HIE时有协同作用,疗效显著,未见副作用发生. 相似文献
107.
Soluble Fcγ-binding components were detected in gingival fluid from periodontal lesions by incubation with biotinylated human Fcγ fragments. FcγIII receptor was identified by incubation of gingival fluid with monoclonal antibody. Sodium dodecyl sulfate-polyacrylamide gel electophoresis and Western transfer showed that most of the Fcγ-binding components had minimal mobility in a 4–15% gradient gel under nonreducing conditions. Under reducing conditions, the main band of Fcγ-binding components in gingival fluid migrated corresponding to protein A of 49 kDa. The pattern of Fcγ-binding components was similar in serum and gingival fluid except for the observation in gingival fluid of Fcγ-binding components migrating like standard proteins of 19 to 20 kDa, a size that corresponds to the polypeptide part of FcγII receptor and FcγIII receptor. 相似文献
108.
糖尿病肾脏胶原非酶糖化与氨基胍阿斯匹林的治疗作用 总被引:1,自引:0,他引:1
本实验系统观察了STZ所致糖尿病鼠在1、3、6个月后肾脏组织胶原发生非酶糖化的情况,及氨基胍、阿斯匹林对肾脏胶原非酶糖化的阻断作用。结果表明:各病程糖尿病动物肾组织的胶原含量和非酶糖化早期产物(5-HMF)及胶原相联荧光值均明显高于正常对照。氨基胍能够减弱糖尿病动物肾组织胶原含量的增加和荧光产物的生成,但对5-HMF含量无影响。阿斯匹林未显示出对胶原非酶糖化的影响。 相似文献
109.
钱文艺 《中华现代医院管理杂志》2007,5(9):26-27
当前部队医院正处于发展转型期,如何引导科技干部适应转型发展新形势,经受住各种考验,始终保持理性平和、协调平衡、积极向上的心理状态,是一个不容忽视的现实问题,也是事关医院内部和谐和医院建设发展又好又快的大事,更是我们思想政治工作者必须着力认真研究、加以解决的重要课题。 相似文献
110.
北京市宣武区中学生生殖健康知识调查分析 总被引:1,自引:0,他引:1
【目的】掌握青少年性发育特点,以便开展有针对性的青春期生殖健康教育,提高自我保护能力,使其健康的成长。【方法】重点高中2所、普通高中4所、职业高中3所,分别选择同年级、同号班级22个班的1 800名高中生,由专门调查员进班发问卷,要求学生在15 min内完成。学生填写问卷时,采用校方人员回避,问卷不记名方式,填写后当场封存,确保学生的隐私权。【结果】调查学生中生理知识知晓率达到70.74%,性病、艾滋病方面知识知晓率达53.9%,相关避孕知识知晓率15%,学生中的性活动发生率17.9%,缺乏保护意识的学生占25.4%,接触过淫秽品的学生43.5%,对婚前性行为的看法持开放态度的学生占38%。【结论】学生的性观念开放,综合自我保护能力较低,易受疾病和社会危险因素伤害,对其成长过程造成障碍。 相似文献