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   1254篇
  免费   87篇
  国内免费   58篇
妇产科学   1篇
基础医学   88篇
口腔科学   115篇
临床医学   72篇
内科学   31篇
皮肤病学   7篇
神经病学   13篇
特种医学   29篇
外科学   50篇
综合类   342篇
预防医学   89篇
眼科学   6篇
药学   60篇
  2篇
中国医学   471篇
肿瘤学   23篇
  2024年   9篇
  2023年   28篇
  2022年   47篇
  2021年   44篇
  2020年   29篇
  2019年   32篇
  2018年   15篇
  2017年   22篇
  2016年   34篇
  2015年   38篇
  2014年   63篇
  2013年   55篇
  2012年   60篇
  2011年   84篇
  2010年   67篇
  2009年   58篇
  2008年   87篇
  2007年   65篇
  2006年   72篇
  2005年   75篇
  2004年   65篇
  2003年   54篇
  2002年   40篇
  2001年   47篇
  2000年   41篇
  1999年   32篇
  1998年   12篇
  1997年   20篇
  1996年   18篇
  1995年   12篇
  1994年   17篇
  1993年   15篇
  1992年   14篇
  1991年   8篇
  1990年   11篇
  1989年   3篇
  1988年   2篇
  1987年   3篇
  1985年   1篇
排序方式: 共有1399条查询结果,搜索用时 15 毫秒
1.
阻塞性睡眠呼吸暂停低通气综合征(OSAHS)是对人类健康有重要影响的临床疾病之一,越来越受到人们的重视;但从流行病学角度认识这个疾病还存在一些问题。疾病的相关研究通常是要兼顾宏观和微观的;虽然近年来微观研究已进入分子生物学时代,宏观的流行病学研究仍不容忽视。  相似文献   
2.
笔者在临床工作中,经过反复思考与验证,结合现代医药理论与成果探讨中医药治疗癌症的思路,提出癌症治疗中宏观与微观辩证的方法,以供讨论。  相似文献   
3.
综述了近年来在核医学中利用微剂量学实验方法研究放射性药物在生物体内微剂量分布的工作,介绍了微观放射自显影术。这里的微剂量分布是指细胞与亚细胞水平的剂量分布。只有掌握了准确的微剂量分布信息,才能较好地预测及评价放射性药物的诊断和治疗效果。  相似文献   
4.
5.
羟基磷灰石(HA)是一种生物相容性的骨替代材料,不同孔隙率的HA具有不同的表面形貌。本实验旨在研究HA的表面形貌对大鼠骨髓细胞向成骨细胞分化的影响。  相似文献   
6.
2型糖尿病(消渴病)微观辨证的临床研究   总被引:4,自引:0,他引:4  
目的 为糖尿病的临床辨证、治疗用药提供客观依据和帮助。方法 观察 2型糖尿病 (消渴病 ,diabetesmellitus)不同证型患者各 30例 ,正常对照组 30例 ,检测血清一氧化氮 (NO)、血浆α -颗粒膜蛋白 (GMP 14 0 )、血浆D -二聚体 (D D)、血清白细胞介素 - 6 (IL 6 )这些微观指标的变化 ,探讨其与中医辨证分型的关系。结果 ①血清NO值在各组中的变化是阴虚热盛组 >正常对照组>气阴两虚组 >气滞血瘀组 ,每两组间具有显著性差异 (P <0 0 5 ) ,其中气滞血瘀组与其它 3组具有非常显著性差异 (P <0 0 1)。②糖尿病各组患者血浆GMP 14 0、D D值均较正常对照组有非常显著性增高 (P <0 0 1) ,在糖尿病组各证型中 ,呈阴虚热盛组 <气阴两虚组 <气滞血瘀组变化趋势 ,且血浆GMP 14 0和D D的变化呈正相关 (r=0 6 6 )。③血清IL 6在糖尿病组较正常对照组升高 ,其变化呈阴虚热盛组 <气阴两虚组 <气滞血瘀组趋势 ,每两组间具有非常显著性差异 (P <0 0 1)。结论 糖尿病发病以正气不足为内在依据。随着病程的进展 ,脾肾亏虚及血瘀加重是必然趋势。治疗应重视补脾肾和活血化瘀  相似文献   
7.
8.
最近在中国画院观看了上海中医药大学匡调元教授的画展——"生命微观意象艺术"。初看其画,颇有西方现代派抽象主义的韵味,如有的画面就有点象米罗的作品。谈起他的画,匡教授认为,这不是老来闲趣,而是对生命科学的一种思索。看完画展,笔者也陷入了沉思:所谓对生命科  相似文献   
9.
BACKGROUND: It has been demonstrated that curcumin can increase the activities of various anti-oxidase in blood and tissue, effectively eliminate various free radicals, reduce the production of peroxisome, and alleviate oxidative stress reaction. Whether it has the same effect on microglia? OBJECTIVE: To observe the effects of curcumin on the expressions of inducible nitric oxide synthase (iNOS), nuclear factor-κB (NF-κB), and superoxide dismutase (SOD) in microglial cell line BV stimulated by lipopolysaccharide (LPS). DESIGN: An observational comparative study. SETTING: Research Room of Biochemistry, Medical College of Nantong University. MATERIALS: Mice microglia cell line BV, iNOS and NF-κB reporter gene plasmids were presented by Dr. Bhat.NR. from the Medical University of South Carolina (USA). Curcumin was produced by the Xi'an Branch of China Chengdu Scholar Bio-Tech. Co.,Ltd.; LPS (E.Coli O26:B6), anti-mice iNOS monoclonal antibody, horseradish peroxidase labeled goat-anti-mice IgG were the products of Sigma Company (USA). METHODS: The experiments were carried out in the Research Room of Biochemistry, Medical College of Nantong University from May 2006 to April 2007. ① Detection of iNOS: The cells were seeded onto 24-well plate at the density of 1×105, After the cells had adhered to the cover glasses, the cells were grouped as negative control group (the primary antibody was replaced by phosphate buffered solution PBS); normal control group (the cells were normally cultured); LPS-treated group (the cells were treated with LPS for 24 hours); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours). The expressions of iNOS protein were detected with immunocytochemical staining. ② Determination of iNOS and NF-κB gene activities: According to the introduction of the kit for transfection, iNOS or NF-κB report gene plasmids were transiently transfected with LipofectamineTM2000 liposomes into the cells in the 24-well plate for 24 hours. The cells were divided into normal control group (the cells were normally cultured after transfected with report gene plasmids); blank plasmid group (the cells were normally cultured after transfected with blank plasmids); LPS-treated group (the cells were treated with LPS for 4 hours after transfected with report gene plasmids); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours after transfected with report gene plasmids). The content of luciferase in the cell lysis buffer was determined after cell lysis. ③ Determination of SOD activity: The cells were seeded into culture bottle at the density of 1×106, and the divided into four groups, including normal control group (the cells were normally cultured); LPS-treated group (the cells were treated with LPS for 24 hours); curcumin+LPS group (the cells were treated with curcumin for 1 hour and LPS for 24 hours); vitamin C+LPS group (the cells were treated with vitamin C for 1 hour and LPS for 24 hours). The SOD activity was determined with xanthine oxidase and quantitative colorimetric assay. MAIN OUTCOME MEASURES: The expressions of iNOS protein, iNOS and NF-κB, and the activity of SOD were observed. RESULTS: ① Expression of iNOS protein in microglia: The expression of iNOS protein in the LPS-treated group was obviously higher than that in the negative control group (P < 0.01); Those in the curcumin+LPS group were significantly decreased as compared with that in the LPS-treated group (P < 0.01). ② Expressions of iNOS and NF-κB genes: The expressions of iNOS and NF-κB genes in the LPS-treated group were significantly higher than those in the normal control group (P < 0.01); Those in the curcumin+LPS group were significantly lower than those in the LPS-treated group (P < 0.01). ③ SOD activity: The activity of SOD in the LPS-treated group was significantly lower than those in the normal control group (P < 0.01). It in the curcumin+LPS group and vitamin C +LPS group was significantly higher than that in the LPS-treated group (P < 0.01). CONCLUSION: Curcumin could inhibit the expression of iNOS in the activated microglia, and it also has the abilities in eliminating free radicals and antagonizing lipid peroxidation.  相似文献   
10.
目的探讨放射免疫治疗中α核素在细胞水平上非均匀微观分布对细胞S因子的影响。方法利用蒙特卡罗方法随机模拟α粒子的发射;基于连续慢化近似模型,根据α粒子剩余射程-能量的关系,采用插值法计算α粒子入射动能和出射动能,得到其在靶区内的能量沉积。以213Po为例,计算了不同细胞大小及核素不同微观分布(均匀分布、中心分布、随核素距细胞中心的距离线性递增、线性递减、指数递增、指数递减)下细胞对细胞的S因子。结果213Po均匀分布下的S(C←C)与Hamacher给出的结果符合得很好;不同微分布下的S(C←C)有显著差别。分析表明,核素不同微观分布所造成的α粒子在靶区内运动的平均弦长的显著变化,以及由此产生的α粒子平均碰撞阻止本领的变化,是造成细胞S因子有显著差别的主要原因。结论放射性核素非均匀微分布类型显著影响细胞S因子的大小,在估算细胞吸收剂量时应予以重视。  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