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   331篇
  免费   22篇
  国内免费   2篇
耳鼻咽喉   8篇
儿科学   2篇
妇产科学   12篇
基础医学   67篇
口腔科学   3篇
临床医学   18篇
内科学   77篇
神经病学   12篇
特种医学   8篇
外科学   29篇
综合类   2篇
预防医学   27篇
眼科学   14篇
药学   24篇
中国医学   4篇
肿瘤学   48篇
  2024年   1篇
  2023年   2篇
  2022年   4篇
  2021年   15篇
  2020年   9篇
  2019年   15篇
  2018年   17篇
  2017年   8篇
  2016年   18篇
  2015年   13篇
  2014年   15篇
  2013年   23篇
  2012年   24篇
  2011年   32篇
  2010年   10篇
  2009年   15篇
  2008年   18篇
  2007年   18篇
  2006年   18篇
  2005年   24篇
  2004年   12篇
  2003年   9篇
  2002年   8篇
  2001年   9篇
  2000年   5篇
  1999年   5篇
  1998年   1篇
  1997年   1篇
  1993年   1篇
  1991年   2篇
  1990年   2篇
  1988年   1篇
排序方式: 共有355条查询结果,搜索用时 31 毫秒
1.
The aim of this study was to compare nonfluoroscopic electroanatomic mapping (NOGA), SPECT perfusion imaging, and PET metabolic imaging for assessment of myocardial viability. In particular, we sought to elucidate differences of electromechanical properties between the perfusion/metabolism mismatch as an indicator of a potentially reversible ischemic injury and the perfusion/metabolism match indicating irreversibly damaged myocardial tissue. METHODS: Twenty-one patients with coronary artery disease underwent NOGA mapping of endocardial unipolar voltage, cardiac 18F-FDG PET of glucose utilization, and resting 201Tl SPECT of myocardial perfusion. RESULTS: Electrical activity was 10.8 +/- 4.6 mV (mean +/- SD) in normal myocardium and was unchanged in hypoperfused segments with maintained glucose metabolism (perfusion/metabolism mismatch), 9.3 +/- 3.4 mV (P = not significant). In contrast, hypoperfused segments with a perfusion/metabolism match and nonviable segments showed significantly lower voltage (6.9 +/- 3.1 mV, P < 0.0001 and 4.1 +/- 1.1 mV, P < 0.0001 vs. normal). In hypoperfused segments, metabolic activity was more closely related to endocardial voltage than was myocardial perfusion (201Tl vs. voltage: r = 0.38, SEE = 3.2, P < 0.001; 18F-FDG PET vs. voltage: r = 0.6, SEE = 2.8, P < 0.0001). CONCLUSION: In hypoperfused myocardium, electrical activity by NOGA mapping is more closely related to PET metabolic activity than to SPECT myocardial perfusion. As NOGA mapping does not differentiate hypoperfused myocardium with enhanced glucose utilization from normal myocardium, results from NOGA mapping need to be correlated with results from perfusion imaging to identify hypoperfused, yet viable, myocardium and to stratify patients for revascularization procedures.  相似文献   
2.
It is well known that Beh?et's disease (BD) is strongly associated with human leukocyte antigen (HLA) B51 in many ethnic groups. However, there has been no published report as yet with respect to this association among the Iranian people. Furthermore, since it is now known that the B51 antigen can be encoded by 21 alleles, B*5101-B*5121, we performed HLA-B*51 allele typing as well as HLA class I genotyping of 48 Iranian patients with this disease. As a result, the frequency of the B*51 allele was significantly higher (62.1%) in the patient group as compared with the ethnically matched control group (31.8%) (Pc=0.067, R.R.=3.51). In the genotyping of B*51 alleles, 33 out of the 36 B*51-positive patients possessed B*5101 and the remaining 3 carried B*5108. This study revealed that Iranian patients with BD also had a strong association with HLA-B51. In addition, this significantly high incidence of HLA-B*51 was found to be caused by an increase in both the HLA-B*5101 and HLA-B*5108 alleles. However, there was no significant difference in the HLA-B*51 allelic distribution between the patient and control groups.  相似文献   
3.
The use of different coping strategies, measured by the Ways of Coping Questionnaire was investigated among 1157 women (18 to 30 years), randomly selected from the general population of Sweden as part of a longitudinal study. Subjects were clustered into five groups: subjects with past or current eating disorders (ED), and subjects with no ED but with past, current, or no history of dieting. Subjects with past or current ED reported significantly higher levels of escape avoidance and lower levels of seeking social support and purposeful problem solving compared with subjects with neither ED nor dieting. These group comparisons were then reanalyzed with sum of depressive symptoms as a covariate in covariate analyses. The only significant difference between the groups concerned the use of escape avoidance. The significant differences in the use of escape-avoidance strategies may motivate more extensive training in coping in the context of prevention and treatment of ED and maladaptive dieting.  相似文献   
4.

Background

Endotoxemia is a major cause of mortality in large animals and there are several therapeutic regimens for the treatment of endotoxemia. Recent studies have suggested the anti-inflammatory effects of insulin in endotoxemic human and laboratory animal models but to the best of our knowledge there is no report on the possible therapeutic effect of insulin in large animal endotoxemia.

Objective

This experiment was conducted to evaluate the anti-inflammatory effects of insulin regular compared with flunixin meglumine on the treatment of endotoxemia in sheep.

Methods

Lipopolysaccharide from Escherichia coli was administered intravenously to ewes. Anti-inflammatory effects of flunixin meglumine (at 2.2 mg/kg) and insulin regular (at 1.5 and 3 IU/kg) were evaluated by determination of serum concentrations of acute phase proteins, inflammatory cytokines and oxidative stress biomarkers.

Results

Insulin regular at 3 IU/kg controlled the acute phase response following endotoxemia induction. The anti-inflammatory potency of insulin regular at 3 IU/kg was significantly higher than at 1.5 IU/kg and of flunixin meglumine at 2.2 mg/kg (P < 0.05).

Conclusion

Insulin regular induces its anti-inflammatory effects in a dose-dependent manner. Intravenous use of insulin regular can be a potential new therapeutic regimen for endotoxemia in large animal medicine.  相似文献   
5.

Background

Guidelines for reperfusion in ST-elevation myocardial infarction (STEMI) were recently adopted by the Canadian Cardiovascular Society. We have developed a blended model of prehospital thrombolytic (PHL) therapy or primary percutaneous coronary intervention (PPCI) activation, in order to achieve guideline times.

Methods

In our urban centre of 658,700 people, emergency medical services (EMS) were trained to perform and screen electrocardiograms (ECGs) for suspected STEMI. Suspected ECGs were transmitted to a physician's hand-held device. If the physician confirmed the diagnosis they coordinated initiation of either PHL or PPCI. In cases where physicians found the prehospital ECG negative for STEMI (PHENST), patients were transported to the closest emergency room.

Results

From July 21, 2008 to July 21, 2010, the Cardiac Outcomes Through Digital Evaluation (CODE) STEMI project received 380 transmitted calls. There were 226 confirmed STEMI by the on-call physician, 158 (70%) received PPCI, 48 (21%) received PHL, and 20 (9%) had angiography but no revascularization. The PPCI, median time from first medical contact to reperfusion was 76 minutes (interquartile range [IQR], 64-93). For PHL, median time from first medical contact to needle was 32 minutes (IQR, 29-39). The overall mortality rate for the STEMI patients was 8% (PHL = 4 [8.3%], PPCI = 8 [5%], medical therapy = 7 [35%]). There were 154 PHENST patients, 44% later diagnosed with acute coronary syndrome. The mortality rate for PHENST was 14%.

Conclusions

Through a model of EMS prehospital ECG interpretation, digital transmission, direct communication with a physician, and rapid coordinated service, we demonstrate that benchmark reperfusion times in STEMI can be achieved.  相似文献   
6.
7.
International Ophthalmology - The present study was done to evaluate efficiency of an ensemble learning structure for automatic keratoconus diagnosis and to categorize eyes into four different...  相似文献   
8.
Implicit pro-thin/anti-fat attitudes were investigated among a mixed group of patients with full and sub-threshold Anorexia Nervosa (n = 17), and a matched-age control group (n = 17). The Implicit Relational Assessment Procedure (IRAP) was employed to measure implicit pro-thin and anti-fat attitudes towards Self and Others in addition to “striving for thinness” and “avoidance of fatness.” The clinical group showed an implicit pro-fat attitude towards Others and stronger anti-fat attitudes towards Self and avoidance of fatness compared with controls. The findings are discussed in relation to the over-evaluation of weight and shape in the clinical group.  相似文献   
9.

Background

Roux-en-Y gastric bypass (RYGB) patients report significant pre- to post-surgery increases in physical activity (PA). Conversely, objectively assessed PA does not increase after RYGB. The aim of the study was to compare self-reported and accelerometer-measured changes in moderate-to-vigorous PA (MVPA) and exercise from pre- to post-surgery, in women undergoing RYGB.

Methods

Forty-three women with an average pre-surgery body mass index of 39.2 kg/m2 (SD 3.1) were recruited at Swedish hospitals. PA was measured by the Actigraph GT3X+ and by a previously validated short PA questionnaire, at home visits 3 months before and 9 months after surgery, thus limiting seasonal effects.

Results

Self-reported time spent in exercise increased with 75 % and time spent in MVPA increased with 51 %, whereas accelerometer-assessed time spent in exercise increased with 0.9 % and time spent in MVPA increased with 2.1 %, from before to after surgery. Correlations comparing accelerometers with the questionnaire were 0.35 (P?=?0.02) for MVPA and 0.13 (P?=?0.4) for exercise before RYGB and 0.52 (P?≤?0.001) for MVPA and 0.12 (P?=?0.4) for exercise after RYGB.

Conclusions

Pre- to post-RYGB surgery increases in self-reported PA were not confirmed by accelerometer-measured PA. Thus, health care workers should use objective measures of PA in patients undergoing RYGB, in order to assess whether patients achieve sufficient levels of PA.
  相似文献   
10.

Introduction

Food allergy refers to abnormal reactions of the body caused by an immune system response to food. This study was conducted aiming to investigate allergy to food allergens in children with food allergies.

Materials and methods

This study was conducted as a cross-sectional one on 304 children aged six months to seven years with food allergies admitted to the tertiary referral hospital in Kurdistan Province – Iran, during 2014–2015. All the patients were examined for skin prick test using 49 allergens. Finally, the obtained data were analysed using SPSS15 and chi-square and t tests.

Results

The highest percentage of occurrence of bump reaction (wheal) and redness (flare) was due to the consumption of fish, eggs, tomatoes, and cocoa. Moreover, the lowest rate of wheal and flare was caused by exposure to allergens like latex, tea, malt, and wheat flour. The reaction most created due to the consumption of foods was flare which was higher among under three-year-olds group (p < 0.05), and between the sexes, girls showed the most common allergic reactions (p < 0.05).

Conclusion

Since food allergy has a high prevalence in children, it should be considered with great interest. Considering that avoiding food allergens is the first step in the treatment of food allergies, the present study may be a useful guide in this regard.  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