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   3473篇
  免费   162篇
  国内免费   49篇
耳鼻咽喉   62篇
儿科学   42篇
妇产科学   24篇
基础医学   363篇
口腔科学   76篇
临床医学   211篇
内科学   874篇
皮肤病学   24篇
神经病学   305篇
特种医学   126篇
外科学   765篇
综合类   9篇
预防医学   73篇
眼科学   16篇
药学   236篇
中国医学   7篇
肿瘤学   471篇
  2023年   26篇
  2022年   50篇
  2021年   104篇
  2020年   48篇
  2019年   49篇
  2018年   74篇
  2017年   50篇
  2016年   99篇
  2015年   96篇
  2014年   97篇
  2013年   141篇
  2012年   231篇
  2011年   248篇
  2010年   124篇
  2009年   130篇
  2008年   199篇
  2007年   209篇
  2006年   209篇
  2005年   219篇
  2004年   228篇
  2003年   216篇
  2002年   226篇
  2001年   47篇
  2000年   37篇
  1999年   48篇
  1998年   50篇
  1997年   47篇
  1996年   41篇
  1995年   36篇
  1994年   34篇
  1993年   18篇
  1992年   26篇
  1991年   29篇
  1990年   28篇
  1989年   16篇
  1988年   17篇
  1987年   16篇
  1986年   9篇
  1985年   12篇
  1984年   20篇
  1983年   11篇
  1982年   9篇
  1981年   7篇
  1980年   11篇
  1979年   5篇
  1977年   4篇
  1976年   5篇
  1972年   4篇
  1970年   4篇
  1967年   3篇
排序方式: 共有3684条查询结果,搜索用时 11 毫秒
71.

The effects of the water extract of Sinomeni Caulis et Rhizoma (SCR-WE) and its major constituents, sinomenine (SIN) and magnoflorine (MAG), on moderate hemolysis induced by lysophosphatidylcholine (LPC) were investigated in rat erythrocytes and compared with the anti-hemolytic effects of lidocaine (LID) and propranolol (PRO) as reference drugs. LPC caused hemolysis at concentrations above the critical micelle concentration (CMC), and the concentration of LPC producing moderate hemolysis (60 %) was approximately 10 μM. SCR-WE at 1 ng/mL–100 μg/mL significantly inhibited the hemolysis induced by LPC. SIN and MAG attenuated LPC-induced hemolysis in a concentration-dependent manner from very low to high concentrations (1 nM–100 μM and 10 nM–100 μM, respectively). In contrast, the inhibiting effects of LID and PRO on LPC-induced hemolysis were observed at higher concentrations (1–100 μM) but not at lower concentrations (1–100 nM). Neither SIN nor MAG affected micelle formation of LPC, nor, at concentrations of 1 nM–1 μM, did they attenuate the hemolysis induced by osmotic imbalance (hypotonic hemolysis). Similarly, SCR-WE also did not modify micelle formation or hypotonic hemolysis, except at the highest concentration. These results suggest that SIN and MAG potently protect the erythrocyte membrane from LPC-induced damage and contribute to the beneficial action of SCR-WE. The protective effects of SIN and MAG are mediated by some mechanism other than prevention of micelle formation or protection of the erythrocyte membrane against osmotic imbalance.

  相似文献   
72.
Journal of Gastroenterology - Sarcopenia prevalence has increased in proportion to the aging population in Japan. We aimed to investigate the association between sarcopenia and clinical outcomes...  相似文献   
73.
74.
75.
76.
Cine-magnetic resonance imaging (cine-MRI) creates moving pictures by a video system and turbo-flash method that allow for high-speed MRI. This report describes our experience using this new technique for dynamic imaging using the fast spoiled GRASS (SPGR) sequence to study swallowing in patients with dysphagia following radical surgery for oral cancer. We defined two new parameters, laryngeal elevation and the angle of the epiglottis, to quantify swallowing ability by cine-MRI. These variables were markedly different in patients with dysphagia than they were in healthy controls. Cine-MRI not only provides dynamic images of swallowing but can generate objective measures of swallowing ability as well.  相似文献   
77.
78.
No strategies for the diagnosis and treatment of biliary tract carcinoma have been clearly described. We developed flowcharts for the diagnosis and treatment of biliary tract carcinoma on the basis of the best clinical evidence. Risk factors for bile duct carcinoma are a dilated type of pancreaticobiliary maljunction (PBM) and primary sclerosing cholangitis. A nondilated type of PBM is a risk factor for gallbladder carcinoma. Symptoms that may indicate biliary tract carcinoma are jaundice and pain in the upper right area of the abdomen. The first step of diagnosis is to carry out blood biochemistry tests and ultrasonography (US) of the abdomen. The second step of diagnosis is to find the local extension of the carcinoma by means of computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), percutaneous transhepatic cholangiography (PTC), and endoscopic retrograde cholangiopancreatography (ERCP). Because resection is the only way to completely cure biliary tract carcinoma, the indications for resection are determined first. In patients with resectable disease, the indications for biliary drainage or portal vein embolization (PVE) are checked. In those with nonresectable disease, biliary stenting, chemotherapy, radiotherapy, and/or best supportive care is selected.  相似文献   
79.
Beta-1-adrenergic receptor (beta1-AR) blockers reduce both the incidence of sudden death and the ventricular volume in heart failure. In vitro, the Gly389 variant of beta1-AR mediates less adenylyl cyclase activities than the Arg389 variant, so Arg389Gly polymorphism was investigated with regard to the genesis, progression, or arrhythmogenesis of dilated cardiomyopathy (DCM). Allele and genotype frequencies of the Arg389Gly polymorphism were determined in 163 DCM patients and 157 age- and sex-matched controls. There were no differences in genotype and allele frequencies between patients and controls. Echocardiograms, left ventriculograms and 24h-Holter electrocardiograms were evaluated in the DCM patients and none of the clinical indices, other than ventricular tachycardia (VT), differed among the 3 genotypes. The Gly389 allele was more frequent in the VT(-) group than in the VT(+) group (0.46 vs 0.24, p=0.001). In univariate analysis, the odds ratio for VT in patients carrying 1 or 2 copies of the Gly389 allele was 0.29 ([95% confidence interval, 0.13-0.64], p=0.002), when compared with the Arg389 homozygotes. The Gly389 variant supressed the occurrence of VT in DCM, suggesting that this allele confers a decreased risk of sudden death.  相似文献   
80.
We report a case of septicemia type Vibrio vulnificus infection. The patient was a 74-year-old man who had liver cirrhosis and hepatocelluler carcinoma. He felt a pain in the right femoral lesion after eating raw shellfish (Japanese "Umitake") two days ago. He was admitted to our emergency center due to his shock status and thrombocytopenia two days after the onset. We diagnosed necrotizing fasciitis due to Vibrio vulnificus infection, his life was saved by emergency amputation of the right lower extremity. The culture of the blood and vesicle fluid showed Vibrio vulnificus. There are some reports that the debridement was effective to necrotizing fasciitis due to Vibrio vulnificus infection, but these reports are all about single upper extremity lesion. As far as we know, this is the second report of lower extremity necrotiaong fasciitis due to septicemia type Vibrio vulnificus infection rescued by extremity amputation in Japan. The mortality of septicemia type Vibrio vulnificus infection with necrotizing fasciitis is very high, this is quite a valuable report in making a decision for therapy of septicemia type Vibrio vulnificus infection.  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