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   647篇
  免费   47篇
  国内免费   1篇
耳鼻咽喉   1篇
儿科学   34篇
妇产科学   8篇
基础医学   94篇
口腔科学   35篇
临床医学   37篇
内科学   131篇
皮肤病学   9篇
神经病学   68篇
特种医学   20篇
外科学   66篇
综合类   10篇
预防医学   80篇
眼科学   3篇
药学   46篇
中国医学   9篇
肿瘤学   44篇
  2022年   10篇
  2021年   19篇
  2020年   9篇
  2019年   9篇
  2018年   10篇
  2017年   12篇
  2016年   12篇
  2015年   14篇
  2014年   21篇
  2013年   24篇
  2012年   40篇
  2011年   50篇
  2010年   30篇
  2009年   32篇
  2008年   30篇
  2007年   33篇
  2006年   35篇
  2005年   29篇
  2004年   29篇
  2003年   24篇
  2002年   20篇
  2001年   16篇
  2000年   14篇
  1999年   15篇
  1998年   7篇
  1997年   5篇
  1996年   10篇
  1995年   10篇
  1993年   8篇
  1992年   13篇
  1991年   9篇
  1990年   9篇
  1989年   3篇
  1988年   4篇
  1987年   3篇
  1986年   7篇
  1985年   6篇
  1984年   4篇
  1983年   4篇
  1982年   3篇
  1978年   3篇
  1977年   4篇
  1976年   8篇
  1975年   4篇
  1973年   5篇
  1972年   3篇
  1970年   5篇
  1967年   4篇
  1966年   3篇
  1965年   4篇
排序方式: 共有695条查询结果,搜索用时 15 毫秒
1.
This study investigated the association of blood pressure with blood oxidative stress-related parameters in normotensive and hypertensive subjects. A cross-sectional design was applied to 31 hypertensive patients and 35 healthy normotensive subjects. All subjects were men between the ages of 35 and 60 years. Exclusion criteria were obesity, dyslipidemia, diabetes mellitus, smoking and current use of any medication. All patients underwent 24-h ambulatory blood pressure monitoring and sampling of blood and urine. Antioxidant enzymes activity, reduced/oxidized glutathione ratio (GSH/GSSG), and lipid peroxidation (malondialdehyde) were determined in erythrocytes. Parameters measured in the plasma of test subjects were plasma antioxidant status, lipid peroxidation (8-isoprostane), plasma vitamin C and E, and the blood pressure modulators renin, aldosterone, endothelin-1 and homocysteine. Daytime systolic and diastolic blood pressures of hypertensives were negatively correlated with plasma antioxidant capacity (r=-0.46, p<0.009 and r=-0.48, p<0.007), plasma vitamin C levels (r=-0.53, p<0.003 and r=-0.44, p<0.02), erythrocyte activity of antioxidant enzymes, and erythrocyte GSH/GSSG ratio, with hypertensives showing higher levels of oxidative stress. Blood pressures showed a positive correlation with both plasma and urine 8-isoprostane. Neither plasma vitamin E nor the assessed blood pressure modulator levels showed significant differences between the groups or correlation with blood pressures. These findings demonstrate a strong association between blood pressure and some oxidative stress-related parameters and suggest a possible role of oxidative stress in the pathophysiology of essential hypertension.  相似文献   
2.
Foreign bodies embedded in the retina and choroid that cannot be extracted by a magnet and require vitreous surgery for their removal comprise a separate group. A retrospective review of 40 consecutive cases (between 1977-1990) showed that this type of trauma frequently accompanied extensive ocular damage, including corneal and or scleral perforation, disruption of the lens, significant vitreous hemorrhage, retinal and choroid hemorrhage, and retinal detachment. Intraoperative and late complications occurred frequently, making the visual and structural outcomes of such eyes uncertain; therefore, another alternative must be sought that might improve the prognosis of these eyes. In this review, we emphasize (1) the time elapsed between the accident and the removal of the foreign body and (2) the final visual acuity and the time before the surgery.  相似文献   
3.

Background  

Lymph node infarction is known to occur in association with many non-neoplastic and neoplastic conditions however its occurrence in association with DIC is not reported hitherto in the literature.  相似文献   
4.
5.
6.
Preoperative chemoradiotherapy in the treatment of gallbladder cancer   总被引:5,自引:0,他引:5  
Gallbladder cancer is generally associated with a poor prognosis, with local recurrence being the main pattern of failure. In an attempt to improve on the present status of management, we evaluated a prospective Phase II study involving preoperative 5-fluorouracil and radiation. Among 27 eligible patients with a potentially resectable gallbladder cancer detected after cholecystectomy, 18 were treated with preoperative radiation (4500 cGy; 180 cGy/fraction, 5 days/week) concurrent with a continuous infusion of 5-fluorouracil (350 mg/m2/day, days 1-5 and 21-25). Toxicity included leukopenia (8 patients) and thrombocytopenia (7 patients). Delay in surgery due to hematological toxicity was seen in 6 patients. Of the 18 patients, 15 underwent a reoperation. Resection was performed in 13 (86%). Pathologic findings after reoperation revealed residual tumor in both liver and lymph nodes in 3 patients. At a median follow-up of 24 months, 7 patients are alive. Among the patients who died after curative resection, local recurrence was demonstrated in only 1. This is the first report concerning preoperative chemoradiation in gallbladder cancer. To assess its effect on survival, a prospective randomized trial will be necessary.  相似文献   
7.
8.
9.
10.
Dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the population of Santiago (Chile) was determined using a Total Diet Study in the market basket modality. After conducting a survey of the foods consumed in the last 24 h, the most consumed food products were included in the basket. Subsequently, they were cooked or prepared according to typical Chilean procedures and grouped into 17 food categories according to their chemical characteristics. The fish and shellfish group had the highest contents of As (1351 ng/g wet weight, ww), Cd (277 ng/g ww), and Hg (48 ng/g ww), while the sugar group had the highest content of Pb (251 ng/g ww). For a person with a body weight of 68 kg, the dietary intakes of As (77 microg/day), Cd (20 microg/day), Hg (5 microg/day), and Pb (206 microg/day) are lower than the provisional tolerable weekly intake values established by the FAO/WHO. Consequently, the total intakes of As, Cd, Hg, and Pb in Santiago (Chile) are within the limits estimated as safe.  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