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   6065篇
  免费   401篇
  国内免费   26篇
耳鼻咽喉   67篇
儿科学   90篇
妇产科学   154篇
基础医学   1108篇
口腔科学   703篇
临床医学   376篇
内科学   1053篇
皮肤病学   153篇
神经病学   522篇
特种医学   138篇
外科学   507篇
综合类   25篇
一般理论   1篇
预防医学   702篇
眼科学   60篇
药学   501篇
中国医学   57篇
肿瘤学   275篇
  2023年   49篇
  2022年   109篇
  2021年   189篇
  2020年   131篇
  2019年   184篇
  2018年   237篇
  2017年   165篇
  2016年   185篇
  2015年   210篇
  2014年   305篇
  2013年   329篇
  2012年   501篇
  2011年   574篇
  2010年   273篇
  2009年   211篇
  2008年   390篇
  2007年   403篇
  2006年   295篇
  2005年   323篇
  2004年   256篇
  2003年   231篇
  2002年   176篇
  2001年   116篇
  2000年   115篇
  1999年   107篇
  1998年   43篇
  1997年   32篇
  1996年   14篇
  1995年   14篇
  1994年   14篇
  1993年   14篇
  1992年   50篇
  1991年   35篇
  1990年   37篇
  1989年   21篇
  1988年   24篇
  1987年   10篇
  1986年   11篇
  1985年   12篇
  1984年   7篇
  1982年   8篇
  1981年   5篇
  1979年   11篇
  1977年   4篇
  1974年   6篇
  1973年   7篇
  1971年   6篇
  1969年   6篇
  1968年   4篇
  1965年   5篇
排序方式: 共有6492条查询结果,搜索用时 301 毫秒
91.
Articular ultrasound of 6500 joint recesses was performed for the purpose of identifying which joint had the highest measurements among small-sized (SSJ), medium-sized (MSJ) and large-sized (LSJ) joints. Quantitative measurements of synovial hypertrophy (QSR) and semiquantitative measurements of synovial hypertrophy (SSH), power Doppler (SPD) and bone erosion (SBE) (score: 0–3) were made. Higher measurements (p < 0.01) of QSR were obtained in the second metatarsophalangeal joint (MTP), talonavicular joint, and hip. The highest SSH scores (2/3) were obtained in the second MTP, talonavicular joint, hip and knee; the highest SPD scores (1/2/3) in the first MTP, second MTP, dorsal second metacarpophalangeal (MCP) and radiocarpal recesses; and the highest SBE scores (2/3) in the radiocarpal, ulnocarpal and posterior recesses of the glenohumeral joint. In conclusion, higher measurements of synovial hypertrophy were found in the first and second MTPs (SSJ), talonavicular recess (MSJ) and hip (LSJ). Synovial blood flow was frequent in the first MTP and radiocarpal recess. Bone erosion stood out only in the glenohumeral joint.  相似文献   
92.
93.
94.
Apart from its angiogenic and vascular permeation activity, the vascular endothelial growth factor (VEGF) has been also reported as a potent neuronal protector. Newborn rats with low VEGF levels develop neuron degeneration, while high levels induce protective mechanisms in several neuropathological conditions. Phoneutria nigriventer spider venom (PNV) disrupts the blood-brain barrier (BBB) and causes neuroinflammation in central neurons along with excitotoxic signals in rats and humans. All these changes are transient. Herein, we examined the expression of VEGF and its receptors, Flt-1 and Flk-1 in the hippocampal neurons following envenomation by PNV. Adult and neonatal rats were evaluated at time limits of 2, 5 and 24 h. Additionally, BBB integrity was assessed by measuring the expression of occludin, β-catenin and laminin and neuron viability was evaluated by NeuN expression. VEGF, Flt-1 and Flk-1 levels increased in PNV-administered rats, concurrently with respective mRNAs. Flt-1 and Flk-1 immunolabeling was nuclear in neurons of hippocampal regions, instead of the VEGF membrane-bound typical location. These changes occurred simultaneously with the transient decreases in BBB-associated proteins and NeuN positivity. Adult rats showed more prominent expressional increases of the VEGF/Flt-1/Flk-1 system and earlier recovery of BBB-related proteins than neonates. We conclude that the reactive expressional changes seen here suggest that VEGF and receptors could have a role in the excitotoxic mechanism of PNV and that such role would be less efficient in neonate rats.  相似文献   
95.
96.
97.
98.
99.
100.
Maturity-Onset Diabetes of the Young type 4 is a rare form of diabetes mellitus, caused by mutations in the PDX1 gene. However, only a few mutations in this gene have been associated as a cause of monogenic diabetes up to date. It makes difficult to create a clinical manifestation profile of this disease and, consequently, to improve the therapeutic management for these patients. Here we report a normal weight woman, diagnosed with diabetes mellitus at 27 years old, during her first pregnancy. At the time of the recruitment, she was 40 years old and had a body mass index of 23.9 kg/m2, glycated hemoglobin level of 9.6%, and fasting plasma glucose (FPG) of 254 mg/dL. She presented no diabetic complications and she was being treated with insulin. She reported a family history of diabetes mellitus characteristic of an autosomal dominant mode of inheritance. Molecular analysis of the PDX1 gene revealed the missense variant c.532G > A (p.(Glu178Lys)) segregating from the patient to her son, reported as diabetic. It was absent in her healthy daughter. The c.532G > A seems to be a rare variant, absent in human variants databases, and among 86 normoglycemic controls. Eight in silico algorithms classified this variant as probably pathogenic. Additionally, analysis of the evolutionary conservation showed the glutamic acid in the position 178 of PDX-1 protein as conserved among several species. Our findings reinforce the importance of screening rare MODY genes among families with suspicion of monogenic diabetes to help better understand the clinical manifestations of this disease.  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