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   965篇
  免费   48篇
  国内免费   17篇
耳鼻咽喉   5篇
儿科学   53篇
妇产科学   31篇
基础医学   115篇
口腔科学   34篇
临床医学   68篇
内科学   225篇
皮肤病学   56篇
神经病学   67篇
特种医学   50篇
外科学   109篇
综合类   44篇
预防医学   42篇
眼科学   13篇
药学   54篇
中国医学   4篇
肿瘤学   60篇
  2023年   2篇
  2022年   11篇
  2021年   22篇
  2020年   9篇
  2019年   15篇
  2018年   20篇
  2017年   14篇
  2016年   26篇
  2015年   32篇
  2014年   35篇
  2013年   48篇
  2012年   46篇
  2011年   56篇
  2010年   40篇
  2009年   44篇
  2008年   48篇
  2007年   51篇
  2006年   60篇
  2005年   50篇
  2004年   33篇
  2003年   25篇
  2002年   23篇
  2001年   24篇
  2000年   27篇
  1999年   25篇
  1998年   39篇
  1997年   29篇
  1996年   14篇
  1995年   19篇
  1994年   17篇
  1993年   14篇
  1992年   10篇
  1991年   10篇
  1990年   7篇
  1989年   9篇
  1988年   10篇
  1987年   8篇
  1986年   5篇
  1985年   13篇
  1984年   4篇
  1983年   7篇
  1982年   4篇
  1981年   5篇
  1980年   5篇
  1977年   2篇
  1976年   2篇
  1975年   2篇
  1968年   2篇
  1966年   1篇
  1955年   1篇
排序方式: 共有1030条查询结果,搜索用时 640 毫秒
51.
A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance.  相似文献   
52.
The purpose of this study is to evaluate tumor control and failure patterns in patients with low grade gliomas treated with surgery and conventional adjuvant radiation therapy. Twenty-eight patients with low grade gliomas (7 grade I, 21 grade II) were retrospectively evaluated. Extent of resection was gross total (3), subtotal (17), and biopsy alone (8). All grade I tumors underwent subtotal resection. Median radiation therapy dose was 54 Gy delivered to localized fields. Tumor control and patterns of failure were determined from follow-up computed tomography and/or magnetic resonance scans. Median follow-up was 86 months (range, 2.4-177 months). Thirteen patients (46%) (four grade I, nine grade II) developed tumor progression. The 5-year actuarial progression-free survival rates for grade I and grade II patients were 86% and 51%, respectively. Corresponding 5-year actuarial survival rates were 100% and 70%. All recurrences were within the treated volume. Our results reveal that conventional adjuvant radiation therapy is associated with high rates of local tumor progression in both grade II and incompletely resected grade I low grade gliomas. Alternative strategies need to be explored in these patients in an effort to improve tumor control and outcome.  相似文献   
53.
54.
Perez CA  Michalski J  Mansur D 《Rays》2005,30(2):109-120
In the recent past there have been major advances in the management of patients with prostate cancer. New imaging procedures as 3-D CRT and IMRT have played a major role in the tretament of patients with localized prostate cancer. 3-D CRT allows higher doses to be delivered more precisely to the target volume with acceptable organs at risk morbidity. Improved tumor control results in lower incidence of distant metastases and better survival with an enhanced quality of life. This outcome yields a lower cost per treatment of patients over their life time.  相似文献   
55.
The aim of this study was the determination iron and manganese contents in selected herbs, herbal-fruit teas and their water extracts. The samples were mineralized at temperature of 450 degrees C. The iron and manganese contents were determined by atomic absorption spectrometry (AAS) directly from the mineralizates using SOLAAR M5 appliance produced by a US-based Thermo Elemental. The iron contents in dry herbs ranged, at average, from 97.66 to 348.65 microg/g and from 48.95 to 118.40 microg/g in herbal-fruit teas, the manganese contents from 43.25 to 604.80 microg/g in herbs and from 106.75 to 197.00 microg/g in herbal-fruit teas. The iron and manganese contents in dry herbs were comparable to results obtained by authors of the other papers. Infusions and decoctions of the examined herbsand herbal-fruit teas contain the amounts of these elements that do not harm the health and may constitute an additional source of iron and manganese for the human organism.  相似文献   
56.
57.
58.
59.
60.
The paraoxonase (PON) gene family contains at least three members: PON1, PON2, and PON3. The enzyme PON1 has been implicated in the pathogenesis of atherosclerosis. Recently, an association between PON2 and quantitative metabolic phenotypes, such as plasma lipoproteins, plasma glucose, and coronary artery disease (CAD), has been reported. We analyzed two common polymorphisms in PON1 (i.e., M/L55 and R/Q 192 mutations) and PON2 (i.e., G/A148 and C/S311 mutations) in 352 high-risk patients with angiographically defined CAD. These results were compared to those in 380 age- and sex-matched control subjects at high risk for CAD. Polymerase chain reaction with specific primers followed by Hsp92, Alw1, DdeI and Fnu4HI restriction digestion were employed to identify the PON1 M/L55 and R/Q192 and the PON2 G/A148 and C/S311 genotypes, respectively. Univariate analysis showed a higher prevalence of the MM genotype (12% vs. 5%; p=0.004) for the PON1 M/L55 polymorphism and the GG genotype (21% vs. 15%; p=0.047) PON2 G/A148 polymorphism in the control subjects. The PON1 M/L55 mutation (MM genotype) was associated with lower triglyceride levels and the PON2 G/A148 mutation (GG genotype), with higher total and low-density lipoprotein (LDL)-cholesterol levels. No mutation was associated with the number of major coronary artery vessels with a >50% reduction in lumen diameter. Multiple regression analysis disclosed smoking, a family history of CAD, high-density lipoprotein (HDL)-cholesterol and the PON1 M/L55 mutation [OR=0.59 (CI95%: 0.42-0.82); p=0.002] as independent markers for CAD. In contrast to traditional coronary risk factors, the PON1 M/L mutation can be considered predictive of protection against CAD.  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