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   231篇
  免费   7篇
  国内免费   4篇
儿科学   10篇
妇产科学   2篇
基础医学   7篇
口腔科学   1篇
临床医学   107篇
内科学   69篇
皮肤病学   5篇
神经病学   2篇
特种医学   6篇
外科学   6篇
综合类   5篇
预防医学   12篇
药学   8篇
肿瘤学   2篇
  2019年   1篇
  2017年   3篇
  2016年   2篇
  2015年   1篇
  2014年   2篇
  2013年   5篇
  2012年   24篇
  2011年   21篇
  2010年   14篇
  2009年   20篇
  2008年   11篇
  2007年   21篇
  2006年   24篇
  2005年   10篇
  2004年   2篇
  2003年   5篇
  2001年   3篇
  2000年   2篇
  1999年   8篇
  1998年   8篇
  1997年   4篇
  1996年   5篇
  1995年   10篇
  1994年   5篇
  1993年   4篇
  1991年   3篇
  1990年   3篇
  1989年   4篇
  1987年   3篇
  1986年   1篇
  1984年   2篇
  1981年   1篇
  1978年   2篇
  1959年   4篇
  1947年   2篇
  1946年   1篇
  1945年   1篇
排序方式: 共有242条查询结果,搜索用时 15 毫秒
1.
2.
Background: Several collaborations in communicable disease surveillancehave developed between European Union member states. Involvementin these activities takes time and money. It is vital that collaborationsare established in areas most likely to be beneficial. An exercisewas undertaken to inform national surveillance centres and theEuropean Commission as to priority areas for the developmentof collaborations. Methods: A modified Delphi exercise was undertakenamongst the heads of centres with responsibilities for surveillanceat national level in the member states of the EU. Participantsdeveloped, agreed and ranked criteria for developing collaborations.A list of communicable diseases and syndromes was then rankedusing a Likert-type scale. Three rounds were undertaken. Betweenrounds, scores and a ranking were fed back showing where participantshad ranked items, compared to the overall mean and rank distribution.For the third round participants were asked to use a categoricalscale, nominating six or ten high priority disease areas. Results:Response rates were 87.5% for round 1, 44% round 2 and 87% round3. The low round 2 response rate appeared to be because respondentsdid not wish to alter their rankings. The six high priorityareas were outbreaks of gastroenteritis/food poisoning, CID/otherslow virus infections, serious imported diseases, legionellosis,antimicrobial resistance and tuberculosis. When participantsgave ten high priority areas meningococcal disease, travel advice,vaccination/immunization and influenza were also included. Thefinal lists were accepted at the meeting of participants. Conclusions:The process was successful in developing both a priority listand consensus.  相似文献   
3.
This study was designed to examine the effects of nisoldipine(relative to placebo), a new dihydropyridine calcium entry blockingagent, in the treatment of silent ischaemia in conventionaldoses. A total of 409 patients with proven coronary artery diseasewere screened and of this 64 had at least six episodes or atotal duration of 30 mm of ST segment depression (1 mm lastingat least 1 min) over 48 h. Fifty-two patients ultimately completeda randomized double-blind cross-over study comparing nisoldipine5 mg twice a day, nisoldipine 10 mg daily and placebo. There was a reduction in the ST segment integral and numberof episodes of ST segment depression when compared to placeboon treatment with nisoldipine 5 mg twice a day and nisoldipine10 mg daily. However, the confidence limits were wide and crossedthe no-treatment effect line. In addition, the nisoldipine dosesneither affected the circadian distribution of ischaemic episodesnor caused an alteration of the workload achieved either atpeak exercise or at 1 mm ST segment depression measured 24 hafter nidoldipine 10 mg or 12 h after nisoldipine 5 mg. We conclude that frequent silent ischaemia in patients withproven coronary artery disease is relatively uncommon, it accountsfor approximately 16% of patients with positive exercise. Inthese patients nisoldipine, given as 5mg twice a day and 10mg daily, showed no significant therapeutic effects, eitheron the frequency or severity of silent ischaemia. New formulationsof slow release nisoldipine are consequently being developedso that a fuller 24 h therapeutic profile may be obtained.  相似文献   
4.
5.
This study was designed to examine the effects of nisoldipine(relative to placebo), a new dihydropyridine calcium entry blockingagent, in the treatment of silent ischaemia in conventionaldoses. A total of 409 patients with proven coronary artery diseasewere screened and of this 64 had at least six episodes or atotal duration of 30 mm of ST segment depression (1 mm lastingat least 1 min) over 48 h. Fifty-two patients ultimately completeda randomized double-blind cross-over study comparing nisoldipine5 mg twice a day, nisoldipine 10 mg daily and placebo. There was a reduction in the ST segment integral and numberof episodes of ST segment depression when compared to placeboon treatment with nisoldipine 5 mg twice a day and nisoldipine10 mg daily. However, the confidence limits were wide and crossedthe no-treatment effect line. In addition, the nisoldipine dosesneither affected the circadian distribution of ischaemic episodesnor caused an alteration of the workload achieved either atpeak exercise or at 1 mm ST segment depression measured 24 hafter nidoldipine 10 mg or 12 h after nisoldipine 5 mg. We conclude that frequent silent ischaemia in patients withproven coronary artery disease is relatively uncommon, it accountsfor approximately 16% of patients with positive exercise. Inthese patients nisoldipine, given as 5mg twice a day and 10mg daily, showed no significant therapeutic effects, eitheron the frequency or severity of silent ischaemia. New formulationsof slow release nisoldipine are consequently being developedso that a fuller 24 h therapeutic profile may be obtained.  相似文献   
6.
Doppler echocardiographic characteristics of normally functioningAllcarbon prostheses were studied in 149 consecutive patientswith 157 valves in the mitral (n=73) and aortic (n=84) positionswhose function was considered normal by clinical and echocardiographicevaluation. In the mitral position, the mean gradient and theeffective mitral orifice area were not significantly differentin either the 25-mm or the 31-mm size valves (from 5±1to 4±1 mmHg and from 2.2±0.6 to 2.8±0.9cm2, respectively; P=ns for both). Conversely, peak gradientwas significantly and inversely correlated to actual orificearea (r=–0.70; P<0.0006), decreasing from 15±3mmHg in the 25-mm size valve to 9±1 mmHg in the 31-mmsize. In the aortic position, the mean gradient was 29±8 mmHgin the 19-mm size valve; it decreased to 8±2 mmHg inthe 29-mm size. Effective prosthetic aortic valve area, calculatedusing the continuity equation, ranged between 0.9±0.1cm2 for the 19-mm size valve to 4.1±0.7 cm2 for the 29-mmsize. By analysis of variance, effective prosthetic aortic valvearea differentiated various valve sizes (F=25.3; P<0.0001)better than peak (F=5.34; P=0.012) or mean (F=4.34; P=0.0052)gradients alone, and it correlated better with actual orificearea (r=0.89, r=–0.70 and r=–0.65, respectively).This study provides the normal range for Doppler haemodynamiccharacteristics of the various sizes of the Allcarbon valvein the mitral and aortic positions so that prosthetic malfunctioncan be identified.  相似文献   
7.
Summary. On‐demand therapy enables stopping haemorrhages rapidly, reducing joint pain and restoring joint mobility, but does not prevent the beginning and subsequent development of haemophilic arthropathy. The main objective of this study was to identify the clinical and orthopaedic status of severe haemophilic patients with bleeding phenotype receiving on‐demand treatment in Spain. We conducted an epidemiological, observational, retrospective study, recruiting 167 patients from 36 centres (92% of them with haemophilia A), median age at enrolment of 35 years. Forty per cent of the patients received a combination of on‐demand and short‐term prophylaxis regimen; the rest was under on‐demand treatment. One hundred and forty‐five patients (87%) reported at least one bleeding episode and 22 (13%) of the biologically severe patients had no bleeding phenotype. Seventy‐one per cent of the studied population presented established haemophilic arthropathy, reaching 80% if we exclude patients without bleeding phenotype. Forty‐three per cent of these patients had one or two joints affected, 28% of them had three or four affected joints, 20% reported five or six affected joints and 9% more than six injured joints. An increase in established haemophilic arthropathy with age was observed. Forty‐six patients underwent orthopaedic surgery at least once. These data show that on‐demand therapy is not effective in preventing the development of haemophilic arthropathy in severe haemophilic population with bleeding phenotype. Therefore, we suggest that the optimal treatment in these patients should be based on prophylaxis. We recommend analysing the reasons for ending prophylaxis, in case its reinstatement should be necessary.  相似文献   
8.
9.
Early eye contact between mother and baby is considered important in the attachment process between mother and baby. How soon after birth is it possible for eye contact to occur? How soon after birth will a baby open his eyes spontaneously? Where is the baby physically at that time? Is hospital labour ward routine conducive to early eye-to-eye contact between mother and baby? Discussing these questions with midwifery colleagues, it became apparent that we were unable to answer with any degree of certainty, the question ‘How soon after birth will a baby open his eyes spontaneously?’ It was felt that ‘most babies open their eyes at or very soon after birth’. How soon was ‘very soon’? and did all babies open their eyes soon after birth? Were there any observable influencing factors? If so, what were they? In this study of 104 babies, 30 babies opened their eyes at birth, and the remainder, except three, opened their eyes ranging from within 1 minute of birth to within 20 minutes of birth (20 minutes being the time limit set for the study). Some babies were observed to open their eyes momentarily only the very first time, keeping their eyes open longer subsequently.  相似文献   
10.
目的观察中心静脉导管行胸腔闭式引流术与传统胸腔穿刺抽液对结核性渗出性胸膜炎临床疗效。方法治疗组142例应用中心静脉导管行胸腔闭式引流术;对照组140例应用传统胸腔穿刺抽液法每周2次,观察发热、气促改善、胸水吸收时间、并发症等情况。结果平均退热时间、气促缓解时间治疗组较对照组明显缩短,胸水吸收时间治疗组6.92±4.61天,对照组22.57±15.13天,胸膜增厚程度治疗组10.54±8.59mm,对照组19.36±9.87mm,两组有显著性差异(P<0.01)。对照组并发症发生率14.29%,明显高于治疗组14.1%。结论应用中心静脉导管行胸腔闭式引流术,仅需一次性操作,可较快减轻临床症状,缩短治疗时间,并发症少。  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