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   835篇
  免费   87篇
  国内免费   12篇
耳鼻咽喉   8篇
儿科学   14篇
妇产科学   18篇
基础医学   81篇
口腔科学   8篇
临床医学   131篇
内科学   88篇
皮肤病学   5篇
神经病学   44篇
特种医学   232篇
外科学   86篇
综合类   23篇
预防医学   75篇
眼科学   10篇
药学   46篇
中国医学   13篇
肿瘤学   52篇
  2023年   13篇
  2022年   31篇
  2021年   63篇
  2020年   48篇
  2019年   38篇
  2018年   35篇
  2017年   40篇
  2016年   35篇
  2015年   28篇
  2014年   66篇
  2013年   109篇
  2012年   48篇
  2011年   48篇
  2010年   23篇
  2009年   38篇
  2008年   38篇
  2007年   39篇
  2006年   36篇
  2005年   31篇
  2004年   16篇
  2003年   6篇
  2002年   19篇
  2001年   8篇
  2000年   14篇
  1999年   6篇
  1998年   11篇
  1997年   4篇
  1996年   7篇
  1995年   2篇
  1994年   6篇
  1993年   9篇
  1992年   4篇
  1991年   4篇
  1990年   2篇
  1989年   2篇
  1988年   3篇
  1987年   1篇
  1986年   3篇
排序方式: 共有934条查询结果,搜索用时 15 毫秒
1.
BackgroundSecond-hand smoking or environmental tobacco smoke is a critical health risk. Children are the most vulnerable to second-hand smoking because of their small bronchial ducts, less developed immunity, and low-physical activity.ObjectivesThe purpose of this study was to ascertain the effects of second-hand smoking on lung functions in athlete and non-athlete school-aged children.MethodsThis observational study included forty-six school-aged children, their age was 8–15 years, assigned to three groups; 2 study groups and 1 control group (n=15). The study groups comprised of 16 football players, and of 15 cyclists. Lung functions were evaluated recording forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow using digital spirometer.ResultsAll measures were recorded in definite values and the children were also classified into second-hand smoking (SH), or non-exposed to tobacco smoking (NE). The findings presented a significant increase (p<0.05) of the study groups in forced vital capacity, forced expiratory volume in 1 sec and peak expiratory flow solely for the non-exposed children. However, there were non-significant differences between the cyclists and football players or between the passive smoking children and non-exposed children in any of the two study groups (p>0.05).ConclusionThe outcomes of this study suggest beneficial influences of the sports activity on the lung functions, without different influences of the cyclists and football players on the lung functions.  相似文献   
2.
目的 综合评价正念干预对运动员心理康复的效果。方法 检索2010年1月1日至2019年12月31日Web of Science、EBSCO、PubMed、Medline、OpenDissertations、Psychology and Behavioral Sciences Collection、Academic Search Premier、中国知网(CNKI)、维普和万方数据库有关正念干预促进运动员心理康复的研究,对纳入文献进行质量评价,采用Review Manager 5.3软件进行Meta分析。结果 共纳入18项研究。正念干预对运动员心理康复即刻效果呈中到大效应量(d= 0.69, 95%CI 0.53~0.86, P< 0.001),但存在发表偏倚。正念组干预的追踪效应量不显著(d= -0.08, 95%CI -0.33~0.16, P= 0.50)。正念干预的康复效果受研究质量的影响(I2 = 88.1%, P= 0.004)。结论 正念干预对运动员心理康复的效果主要表现为改善心境,促进流畅体验,提高消极体验的接受性,提高对目标的行动力和提高训练的投入程度。正念干预效果受研究质量的影响。  相似文献   
3.
This study looked at the relationship between athletic identity and three levels of sport participation (elite, recreational, non-participation). Athletic identity was measured using the Athletic Identity Measurement Scale (AIMS) with participants being compared on the total AIMS score and scores on its three factors (social identity, exclusivity, negative affectivity). Results indicated that the male non-participation group scored lower on all three factors and the total AIMS when compared to the two athlete groups. The male elite and recreational groups did not differ on exclusivity and negative affectivity but did differ on the total AIMS and social identity, with elite scoring higher than recreational. For female participants, the non-participation group again scored lower on all three factors and the total AIMS when compared to the two athlete groups. The female elite and recreational groups did not differ on negative affectivity but did differ on the total AIMS, social identity, and exclusivity, with elite scoring higher than recreational. Findings suggest that to assume sport is only important to elite athletes ignores the role that sport may play for less talented sport participants. Whilst not seeing themselves as athletes per se, it is suggested that participation in sport may still impact upon the self-perceptions of recreational sport participants. Therefore, threats to participation may result in similar negative consequences for both elite athletes and recreational sport participants.  相似文献   
4.
A 2-week training period 2000 meters above sea level performed by 6 male elite Swedish runners influenced neither basal anabolic (total and non-sex hormone-binding globulin (SHBG)-bound testosterone (NST) and insulin-like growth factor-1 (IGF-1) nor catabolic (cortisol) hormones when comparing serum levels prior to and after the training camp. The anabolic vs catabolic hormone balance, expressed as the NST: cortisol ratio, also remained unchanged as well as SHBG and body mass. Thus, training at 2000 meters above sea level, often practised by elite runners to improve performance in competition at sea level, does not result in a catabolic situation after return to sea level, as measured by peripheral hormones. However, the adaptation to high altitude was associated with a slight (NS) decrease in testosterone as well as in anabolic vs catabolic balance as measured the third day at high altitude. Simultaneously, a decrease in subjective performance was claimed by the runners, but could not be shown by objective measurements. From day 3 to day 9 at high altitude, all runners claimed a subjective recuperation of performance. Total and non-SHBG-bound testosterone increased significantly from day 3 at high altitude to the first post-camp sea-level test. The results reflect the necessity of adaptation when travelling to races at different altitudes. The Swedish runners had significantly higher cortisol, total testosterone and NST levels compared with basal values of a group of 17 elite Kenyan runners living and training at high altitude. Since the NST cortisol and IGF-1 values were not lower, a catabolic state or malnutrition was not likely to be present. The results might reflect an adaptation to altitude or ethnic variations.  相似文献   
5.
BACKGROUND: Turkish children have been found to suffer less from atopic diseases than their German peers. The underlying causes are unknown. OBJECTIVE: To evaluate rates of sensitization and atopic disease among children in Germany with German or Turkish ethnicity and different degrees of cultural adaptation. METHODS: This was a cross-sectional study. The setting was screening for school eligibility in an inner-city district of Berlin/Germany. The participants were preschool children born in Germany with double German or double Turkish parental citizenship. Cultural adaptation of Turkish children was assessed by the language parents used to communicate with their child: only Turkish (n = 60, group A); Turkish and German (n = 269, group B); and only German (n = 103, group C). Group D contained children from German parents (n = 383). The main outcome measures were specific sensitization to common aeroallergens (CAP-System, Pharmacia Phadiatop >or= 0.35 kU/L), and lifetime and 1-year prevalences of allergic disease symptoms (ISAAC questionnaire in German and Turkish, Mantel-Haenszel test for trend). RESULTS: Sensitization rates for groups A, B, C and D were 8.0%, 6.8%, 18.9% and 18.3%, respectively (P = 0.004). The corresponding prevalence rates for wheeze ever were 6.7%, 9.3%, 12.6% and 21.3% (P < 0.001), wheeze in the past year 3.3%, 3.7%, 9.7% and 10.2% (P = 0.001), itchy rash ever 3.3%, 6.3%, 8.7% and 13.7% (P < 0.001), itchy rash in the past year 1.7%, 3.7%, 4.9% and 9.5% (P < 0.001), respectively. No significant differences were found for hay fever symptoms. CONCLUSIONS: Higher cultural adaptation is correlated with higher rates of allergic sensitization and disease among children of Turkish origin living in Berlin. This correlation suggests that environmental rather than genetic differences are responsible for the differences observed.  相似文献   
6.
BACKGROUND: There is increasing recognition that high-performance athletes can develop symptomatic arterial flow restriction in one or both (15%) legs due to kinking and/or endofibrosis of their iliac arteries. METHODS: Case report and review based on a Medline search of the literature. RESULTS: A 51-year-old female, 24-hour endurance runner presented with a six-month history of rapidly progressing intermittent claudication affecting her right thigh and calf in the absence of classical risk factors for atherosclerosis. On the basis of invasive and non-invasive investigations, a provisional diagnosis of endofibrosis was made and she was treated successfully with angioplasty. CONCLUSIONS: The epidemiology, optimal investigation and treatment of iliac endofibrosis in endurance athletes is poorly described. Each individual unit's experience is likely to be very small. A European register of such cases would increase our understanding of the condition and improve patient outcomes.  相似文献   
7.
目的:了解射击运动员高脂血症的发生情况和可能的引发因素,为预防高脂血症提供依据。方法:对从事专业训练半年以上,无急慢性疾病的53名省级优秀射击运动员进行膳食调查和血清脂质水平检测。结果:运动员的高脂血症检出率为28.3%,全部为高甘油三脂血症;膳食中 运动员除了摄入维生素B1、B2不足和维生素A缺乏外,其他各类营养素基本能满足机体需要,属基本合理膳食。结论:以抗阻训练和静力运动为运动特征的射击运动,可能会对机体血脂代谢产生不利的影响。  相似文献   
8.
Nonoperative treatment is generally the choice for Type I and II acromioclavicular (AC) joint injuries. The situation issomewhat more controversial when Type III AC dislocations are considered, particularly with respect to athletes and heavy laborers. A number of recent studies have supported conservative treatment in these groups. There is general consensus as to the need for surgical intervention for Type IV, V, and VI AC injuries. Integral to any form of management, nonoperative or operative, is a rehabilitation program that addresses range of motion, strength, and neuromuscular control. We describe our program, which is divided into four phases: (1) Pain control and immediate protected range of motion and isometric exercises; (2) strengthening exercises using isotonic contractions and proprioceptive neuromuscular facilitation (PNF) exercises; (3) Unrestricted functional participation with the goal of increasing strength, power, endurance, and neuromuscular control; and (4) return to activity with sport specific functional drills. An athlete is ready to return to competitive sports once the following criteria are met: full range of motion (ROM), no pain or tenderness, satisfactory clinical exam, and demonstration of adequate strength on isokinetic testing. The unique considerations in a throwing athlete with an AC injury are also addressed. The primary goal of the nonoperative treatment protocol is to return the athlete to full activities as quickly and as safely as possible.  相似文献   
9.
10.
OBJECTIVE: To examine college athletic trainers' confidence in helping female athletes who have eating disorders. DESIGN AND SETTING: We mailed a 4-page, 53-item survey to head certified athletic trainers at all National Collegiate Athletic Association Division IA and IAA institutions (N = 236). A 2- wave mailing design was used to increase response rate. SUBJECTS: A total of 171 athletic trainers returned completed surveys for a response rate of 77%. Eleven institutions either did not identify their head athletic trainer or did not have an identifiable mailing address. Two surveys were undeliverable because of incorrect mailing addresses. MEASUREMENTS: The survey consisted of 4 subscales: (1) efficacy expectation, (2) outcome expectation, (3) outcome value, and (4) experience in dealing with eating disorders. Content validity was established by review from a national panel of experts. Reliability ranged from.66 to.73 for the subscales. RESULTS: Although virtually all athletic trainers (91%) had dealt with a female athlete with an eating disorder, only 1 in 4 (27%) felt confident identifying a female athlete with an eating disorder, and only 1 in 3 (38%) felt confident asking an athlete if she had an eating disorder. One in 4 athletic trainers (25%) worked at an institution that did not have a policy on handling eating disorders. Almost all athletic trainers (93%) felt that increased attention needs to be paid to preventing eating disorders among collegiate female athletes. CONCLUSIONS: Collegiate athletic programs are encouraged to develop and implement eating-disorder policies. Continuing education on the prevention of eating disorders among athletes is also strongly recommended.  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