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11.
A correlation of the angiographic evolution of coronary stenoses(stenosis diameter 20%) with morphological stenosis parametersat baseline could help to identify the risk of progressive stenoses.Therefore, the data of the prospective INTACT study (InternationalNifedipine Trial on Antiatherosclerotic Therapy) were reviewed.In 348 patients with moderate coronary artery disease, standardizedcoronary angiograms were taken 3 years apart and were quantitativelyanalysed. Changes in the minimal diameter of the 1063 preexistingcoronary stenoses compared between both angiograms were setin relation to a number of conventional stenosis parametersat baseline. Regression analysis demonstrated a significantcorrelation of the changes in minimal diameter with baseline% diameter stenosis (r=0.30; P<0.001), minimal diameter (r=—0.28;P<0.001) and reference diameter of stenoses (r=–0.14;P<0.001). The changes were not correlated with stenosis lengthand plaque area. The baseline parameters of 22 preexisting stenosesprogressing to occlusions differed from those remaining patentonly with regard to the % diameter stenosis (43 ± 9%vs 39 ± 11%; P<0.05). Additional progression of coronarydisease became manifest through development of 228 stenosesand 19 occlusions at arterial sites free from definitive stenosesin the baseline angiograms. Thus, progression of atherosclerosis predominantly occurredin mild preexisting coronary stenoses and developed at previouslyangiographically normal sites. Since the conventional angiographicparameters analysed in this study failed to identify individualarterial sites with an increased risk for progression, definitionof new angiographic parameters or application of new techniquesseem mandatory to this end.  相似文献   
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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   
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An international project (EURONIC) was carried out to explore the end-of-life decision-making process in a large, representative sample of neonatal intensive care units (NICUs) in eight western European countries: France, Germany, Great Britain, Italy, Luxembourg, the Netherlands, Spain and Sweden. Structured questionnaires were used to record data on NICU organization and policies, and to survey staff views and practices regarding ethical decision-making. One hundred and twenty-two NICUs were recruited by census or random sampling (response rate 86%); 1235 physicians and 3115 nurses completed the staff questionnaire (response rates 89 and 85%, respectively). This paper focuses on the physicians' answers. In all countries but Italy, most physicians reported having been involved at least once in setting limits to intensive care because of a baby's incurable condition and/or poor neurological prognosis. Adopted strategies varied between countries. Practices such as the continuation of current treatment without intensifying it and the withholding of emergency manoeuvres appeared widespread. In contrast, the frequency of doctors reporting withdrawal of mechanical ventilation was highest in the Netherlands (93%), Sweden (91%) and the Great Britain (88%), intermediate in France and Germany, and lowest in Spain and Italy (34 and 21%, respectively).
Conclusion: Ethically problematic clinical cases are approached differently in the various countries. The findings of this study may provide an opportunity for physicians to review their practices critically, in light of how other colleagues proceed, and foster an open discussion about these difficult issues.  相似文献   
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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   
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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   
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The aim of this trial was to compare the efficacy of combinationantithrombotic therapy with a prostacyclin-sparing aspirin plusanticoagulation versus conventional aspirin plus anticoagulation,when added to antianginal therapy, in patients with unstableangina or non-Q wave myocardial infarction already being treatedwith aspirin. In a double-blind (for the aspirin) study, 144prior aspirin users were randomized; 72 patients received controiled-release,prostacyclin-sparing aspirin 75 mg daily plus anticoagulation(intravenous heparin followed by warfarin to maintain the internationalnormalized ratio at 2–3), and 72 patients received conventionalaspirin 75 mg daily plus the same anticoagulation. Controlled-releaseaspirin was formulated to preserve endothelial cell prostacyclinsynthesis. Trial therapy was begun by 13.2 ± 12.3 h ofqualifying pain, and continued for 12 weeks. The frequency of recurrent angina with electrocardiographicchanges, myocardial infarction, or death, was analysed by intentionto treat. At 12 weeks, events were  相似文献   
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