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   3085篇
  免费   168篇
  国内免费   12篇
耳鼻咽喉   18篇
儿科学   64篇
妇产科学   64篇
基础医学   466篇
口腔科学   59篇
临床医学   231篇
内科学   886篇
皮肤病学   88篇
神经病学   278篇
特种医学   37篇
外科学   261篇
综合类   17篇
预防医学   279篇
眼科学   34篇
药学   210篇
中国医学   14篇
肿瘤学   259篇
  2023年   30篇
  2022年   52篇
  2021年   106篇
  2020年   65篇
  2019年   88篇
  2018年   95篇
  2017年   73篇
  2016年   76篇
  2015年   96篇
  2014年   119篇
  2013年   160篇
  2012年   211篇
  2011年   263篇
  2010年   127篇
  2009年   133篇
  2008年   225篇
  2007年   221篇
  2006年   206篇
  2005年   203篇
  2004年   177篇
  2003年   163篇
  2002年   152篇
  2001年   17篇
  2000年   5篇
  1999年   15篇
  1998年   20篇
  1997年   16篇
  1996年   20篇
  1995年   16篇
  1994年   15篇
  1993年   6篇
  1992年   10篇
  1991年   6篇
  1990年   4篇
  1989年   6篇
  1983年   3篇
  1982年   5篇
  1980年   3篇
  1978年   3篇
  1977年   3篇
  1976年   3篇
  1974年   3篇
  1973年   3篇
  1966年   2篇
  1961年   2篇
  1941年   3篇
  1940年   3篇
  1938年   2篇
  1934年   2篇
  1918年   2篇
排序方式: 共有3265条查询结果,搜索用时 15 毫秒
991.
It has been reported that the number of circulating endothelial progenitor cells (EPCs) reflects the endogenous vascular repair ability, with the EPCs pool declining in the presence of cardiovascular risk factors. However, their relationship with hypertension and the effects of anti-hypertensive treatment remain unclear. We randomized 29 patients with mild essential hypertension to receive barnidipine up to 20 mg or hydrochlorothiazide (HCT) up to 25 mg. Circulating EPCs were isolated from peripheral blood at baseline and after 3 and 6 months of treatment. Mononuclear cells were cultured with endothelial basal medium supplemented with EGM SingleQuots. EPCs were identified by positive double staining for both FITC-labeled Ulex europaeus agglutinin I and Dil-labeled acethylated low-density lipoprotein. After 3 and 6 months of treatment, systolic and diastolic blood pressure (BP) were significantly reduced. No difference was observed between drugs. An increase in the number of EPCs was observed after 3 and 6 months of anti-hypertensive treatment (p < 0.05). Barnidipine significantly increased EPCs after 3 and 6 months of treatment, whereas no effect was observed with HCT. No statistically significant correlation was observed between EPCs and clinical BP values. Our data suggest that antihypertensive treatment may increase the number of EPCs. However, we observed a different effect of barnidipine and HCT on EPCs, suggesting that, beyond its BP lowering effect, barnidipine may elicit additional beneficial properties, related to a healthier vasculature.  相似文献   
992.
993.
The role of rs1127354/rs7270101 alleles at the inosine triphosphatase (ITPA) gene on ribavirin-induced anemia was assessed in 74 patients with hepatitis C virus and human immunodeficiency virus coinfection. Anemia developed in 80% of patients with normal ITPA activity compared with 33% of those with reduced ITPA activity. In contrast, ITPA variants did not influence sustained virological response.  相似文献   
994.
995.
996.
We have reported of an alternative solution to preserve hepatocytes that have three key components: gluconate, sucrose and an aminosulfonic acid (BGS solution). In order to extend the use of this solution to organs as the liver, we evaluate the effect of the addition of PEG of 8, 20 and 35 kDa to BG Solution on the total water content and functional viability of rat liver microorgans (LMOs). LMOs were preserved (48 h 0 °C) in the following solutions: ViaSpan®; BGS; BG plus 4% PEG 8000 (BG8); BG plus 4% PEG 20.000 (BG20) and BG plus 4% PEG 35.000 (BG35). LDH Release and Total Water Content showed a marked increase in LMOs preserved in BGS. This indicates that, in the absence of PEG, the tissue showed important cell membrane integrity deterioration and was incapable of regulating cell volume. After the preservation period, all groups were reoxygenated (120 min, 37 °C, KHR) and Total Water Content, Glycogen Content and Oxygen Consumption were determined. After 120 min LMOs preserved in BG35 showed values of Oxygen Consumption similar to controls. On the other hand, LMOs preserved in BG8, BG20 and ViaSpan® showed oxygen consumption rates and glycogen content significantly smaller than controls. In conclusion, BG35 was the most effective preservation solution to protect LMOs against cold preservation injury due to ischemia and reoxygenation. It is a good alternative to ViaSpan® because of its higher buffer capacity, its best indexes of respiration activity and for being considerably less expensive.  相似文献   
997.
998.
This report describes a case of variant angina induced by epidural infusion of bupivacaine hydrochloride for the treatment of intractable low back pain in a 66-year-old male patient with lumbar discopathy. Severe reversible coronary artery spasm of right coronary artery was demonstrated by coronary angiography. Withdrawal of epidural anesthesia and treatment with nitrates and calcium channel antagonists resulted in cessation of variant angina.  相似文献   
999.
The Seventh International Symposium on Stem Cell Therapy and Cardiovascular Innovations was held in Madrid on the 6th and 7th of May 2010. Gathering for the seventh consecutive year the most relevant researchers and opinion leaders on cardiovascular cell therapy, it has become the most important worldwide event on this field. A comprehensive review of the last developments on cell therapy, surgery for heart failure and tissue engineering was made, and the results of three clinical trials were reported. The Symposium was dedicated to the memory of Professor Helmut Drexler.  相似文献   
1000.
Questions exist regarding the validity of patient-reporting of psychiatric symptoms in Parkinson's disease (PD). We assessed observer variability and validity in reporting of impulse control disorder (ICD) symptoms in PD by using the Questionnaire for Impulsive-Compulsive Disorders in Parkinson's Disease (QUIP). PD patients and their informants (71 pairs) completed the QUIP to assess four ICDs (compulsive gambling, buying, sexual behavior, and eating) in patients. Trained raters then administered a diagnostic interview. Sensitivity of the QUIP for a diagnosed ICD was 100% for both patient- and informant-completed instruments, and specificity was 75% for both raters. Approximately 40% of patients without an ICD diagnosis had a positive QUIP, suggesting that many PD patients experience subsyndromal ICD symptoms that require ongoing monitoring. Agreement between patient- and informant-reporting of any ICD behaviors on the QUIP was moderate (kappa=0.408), and for individual ICDs was highest for gambling (kappa=0.550). Overall, a negative QUIP from either the patient or informant rules out the possibility of an ICD, while a positive QUIP requires a follow-up diagnostic interview and ongoing monitoring to determine if symptoms currently are, or in the future become, clinically significant.  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