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   1081篇
  免费   65篇
  国内免费   2篇
耳鼻咽喉   20篇
儿科学   33篇
妇产科学   13篇
基础医学   175篇
口腔科学   11篇
临床医学   95篇
内科学   185篇
皮肤病学   44篇
神经病学   26篇
特种医学   45篇
外科学   138篇
综合类   61篇
预防医学   41篇
眼科学   18篇
药学   101篇
中国医学   30篇
肿瘤学   112篇
  2023年   8篇
  2022年   27篇
  2021年   31篇
  2020年   18篇
  2019年   37篇
  2018年   34篇
  2017年   30篇
  2016年   28篇
  2015年   34篇
  2014年   64篇
  2013年   55篇
  2012年   85篇
  2011年   69篇
  2010年   56篇
  2009年   47篇
  2008年   56篇
  2007年   58篇
  2006年   34篇
  2005年   48篇
  2004年   31篇
  2003年   28篇
  2002年   30篇
  2001年   21篇
  2000年   21篇
  1999年   26篇
  1998年   12篇
  1997年   7篇
  1996年   3篇
  1995年   10篇
  1994年   4篇
  1992年   7篇
  1991年   16篇
  1990年   13篇
  1989年   6篇
  1986年   5篇
  1985年   7篇
  1984年   3篇
  1983年   3篇
  1981年   6篇
  1979年   10篇
  1978年   3篇
  1977年   4篇
  1976年   7篇
  1974年   3篇
  1972年   2篇
  1971年   4篇
  1970年   5篇
  1969年   3篇
  1968年   2篇
  1966年   2篇
排序方式: 共有1148条查询结果,搜索用时 703 毫秒
11.
12.
13.
14.
Methods:This study was a retrospective chart review of 1377 patients (2–20 years) undergoing laparoscopic appendectomy for acute appendicitis in 2 tertiary care referral centers from January 2007 through December 2012. Twenty-two different operative technique/dressing variations were documented. The 6 technique/dressing groups with >50 patients were assessed, including a total of 1283 patients.Results:The surgical site infection rate of the 220 patients treated with TULAA and application of an umbilical vacuum dressing with dry gauze is 1.8% (95% CI, 0.0–10.3%). This compares to an infection rate of 4.1% (95% CI, 1.3–10.5%) in 97 patients with dry dressing without vacuum. In the 395 patients who received an umbilical vacuum dressing with gauze and bacitracin, the surgical site infection rate was found to be 4.3% (95% CI, 2.7–6.8%).Conclusions:Application of an umbilical negative-pressure dressing with dry gauze lowers the rate of umbilical site infections in patients undergoing transumbilical laparoscopic-assisted appendectomy for acute appendicitis.  相似文献   
15.
We report the case of a 34-year-old woman with severe post-infectious gastroparesis who was transferred from an outside medical facility for a second opinion regarding management.This patient had no prior history of gastrointestinal symptoms.However,in the aftermath of a viral illness,she developed two months of intractable nausea,vomiting,and oral intake intolerance that resulted in numerous hospitalizations for dehydration and electrolyte disturbances.A solid-phase gastric emptying scan had confirmed delayed emptying,confirming gastroparesis.Unfortunately,conventional pro-kinetic agents and numerous anti-emetic drugs provided little or no relief of the patient’s symptoms.At our institution,the patient experienced a cessation of vomiting,reported a significant reduction in nausea,and toler-ated oral intake shortly after taking mirtazapine.Based on mirtazapine’s primary action as a serotonin(5-HT)1a receptor agonist,we infer that this receptor system mediated the clinical improvement through a combination of peripheral and central neural mechanisms.This report highlights the potential utility of 5-HT1a agonists in the management of nausea and vomiting.We conclude that mirtazapine may be effective in treating symptoms associated with non-diabetic gastroparesis that are refractory to conventional therapies.  相似文献   
16.
17.
18.
Various modeling methods have been proposed to estimate the potential predictive ability of polygenic risk variants that predispose to various common diseases. However, it is unknown whether differences between them affect their conclusions on predictive ability. We reviewed input parameters, assumptions and output of the five most common methods and compared their estimates of the area under the receiver operating characteristic (ROC) curve (AUC) using hypothetical data representing effect sizes and frequencies of genetic variants, population disease risk and number of variants. To assess the accuracy of the estimated AUCs, we aimed to reproduce the AUCs of published empirical studies. All methods assumed that the combined effect of genetic variants on disease risk followed a multiplicative risk model of independent genetic effects, but they either assumed per allele, per genotype or dominant/recessive effects for the genetic variants. Modeling strategy and input parameters differed. Methods used simulation analysis or analytical formulas with effect sizes quantified by odds ratios (ORs) or relative risks. Estimated AUC values were similar for lower ORs (<1.2). When AUCs were larger (>0.7) due to variants with strong effects, differences in estimated AUCs between methods increased. The simulation methods accurately reproduced the AUC values of empirical studies, but the analytical methods did not. We conclude that despite differences in input parameters, the modeling methods estimate similar AUC for realistic values of the ORs. When one or more variants have stronger effects and AUC values are higher, the simulation methods tend to be more accurate.  相似文献   
19.
25 cases of thalassaemia major were studied by 2D and M-mode echocardiography. A significantly increased (p less than 0.001) mean value (100.8 +/- 27.37 msec, range 80 to 140 msec) of A2-E (early relaxation period) interval on M-mode was observed in thalassemia in comparison to mean level (82.6 +/- 5.7, range 60 to 100 msec) of control population. No significant differences were noted in FS % (fractional shortening) and EF% (ejection fraction) when compared to corresponding normal values respectively. Mean serum iron concentration (142.2 +/- 29.1 micrograms/dl, range 102 to 192 micrograms/dl) was significantly higher in thalassaemia as compared to normal population (mean 106.3 +/- 11.4 micrograms/dl, range 75 to 120 micrograms/dl). There was also a direct correlation between serum iron concentration and A2-E interval. 11 patients (44%) showed abnormal A2-E interval but only 3 patients (12%) showed abnormal percentage of FS and EF. It is therefore concluded that A2-E interval will help to detect early left ventricular dysfunction much before overt and irreversible heart failure becomes manifest and which will also help to optimise transfusion and chelation therapy.  相似文献   
20.
We audited the practice of offering, and the uptake of, an HIV antibody test amongst genitourinary medicine clinic patients in the West Midlands region. There were wide variations in the offering (from 14 to 100%) and uptake (18 to 64%) of the test in the different clinics within the same region.  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