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101.
BACKGROUND: For all surgical procedures, a surgeons' learning curve can be anticipated during which complication rates are increased. The aims of this study were to evaluate individual learning curves for a group of surgeons performing laparoscopic fundoplication and to evaluate if the Procedicus MIST-simulator (Mentice Inc., G?teborg, Sweden) accurately predicts surgical performance. METHODS: Twelve Nordic centers participated, each contributing with a "master" and a "pupil" surgeon. The pupils were tested in the simulator and thereafter performed their first 20 supervised operations. All procedures were videotaped and evaluated by 3 independent reviewers. RESULTS: A significant decrease in operative time (P <0.001) and a trend (P = 0.12) toward improved score were seen during the series. The master significantly affected the pupil's score (P =0.0137). The simulator-test showed no correlation with the operative score. CONCLUSIONS: Individual learning curves varied, and the teacher was shown to be the most important factor influencing the pupil's performance score. The correlation between assessed performance and patient outcome will be further investigated.  相似文献   
102.
OBJECTIVE: The aim of the study was to relate cognitive effects of a remote traumatic brain injury (TBI) to MRI findings and severity of injury. METHOD: Sixty-one patients were assessed on average 30 years after a TBI of variable severity. A comprehensive cognitive test battery was used to evaluate memory, executive functions and cognitive overall impairment. Multiple regression analyses were used to examine the relationships between cognitive variables and MRI volumetric findings (the volumes of the hippocampus and the lateral ventricles) and local contusions on MRI. Also, the effect of injury severity on cognitive outcome was evaluated. RESULTS: Reductions in hippocampal volumes and lateral ventricular enlargement were significantly associated with impaired memory functions, memory complaints and executive functions. Of the MRI parameters used, the best predictor for cognitive outcome was the volume of the lateral ventricle. There was only a modest relationship between severity of injury and cognitive performance. CONCLUSIONS: The results show that long-term memory impairments after TBI are associated with MRI volumetric measures. This suggests that the degree of diffuse injury leading to atrophic changes is prognostically more important than the initial severity of TBI.  相似文献   
103.
OBJECTIVES: Chronic anterior knee pain is a common complication following intramedullary nailing of a tibial shaft fracture. The etiology of pain is often not known. This study sonographically examined the patellar tendons of patients with a nailed tibial shaft fracture. DESIGN: Prospective study. SETTING: University hospital. PATIENTS: Fifty consecutive patients with a nailed tibial shaft fracture were initially included in the study. Thirty-six of them could be measured at an average of 2.5 +/- 0.5 years after nail insertion (1.0 +/- 0.3 years after nail extraction). INTERVENTION: Reamed intramedullary nailing with 2 interlocking bolts at both ends of the nail (Grosse-Kempf-nail, Howmedica). MAIN OUTCOME MEASUREMENTS: The ultrasound investigation of the patellar tendons of the 36 patients. RESULTS: Twelve (33%) patients were painless and 24 (67%) patients had anterior knee pain at follow-up. With the reference to the mean difference in the thickness of the distal part of the patellar tendon in the operated limb versus nonoperated limb, the result was 1.4 +/- 1.1 mm in the chronic pain group and 2.6 +/- 2.5 mm in the painless group (P = 0.135, [95% confidence interval for the group difference = -0.4-2.8]). The corresponding values for the proximal part of the patellar tendon was 1.4 +/- 1.3 mm in the chronic pain group and 2.3 +/- 2.3 mm in the painless group (P = 0.251, [95% confidence interval for the group difference = -0.7-2.4]). There were no statistically significantly differences between study groups in the blood circulation of the patellar tendon or at the entry point, calcification of the patellar tendon, granulation tissue at the entry point, or occurrence of low echo areas in the patellar tendon. CONCLUSION: After intramedullary nailing of a tibial shaft fracture, patients with or without anterior knee pain show similar changes in the ultrasound investigation of their patellar tendons. Based on those findings, it does not appear to make any difference as to the approach used (paratendinous or transtendinous) for intramedullary nailing of the tibia.  相似文献   
104.
OBJECTIVES: The aim of the study was to determine the causes of impairment of ventilatory function and diffusing capacity in smoking asbestos-exposed workers (N=590) showing radiological pleural thickenings or pulmonary fibrosis. METHODS: High-resolution computed tomography (HRCT) and spirometry were performed, and diffusing capacity was measured. The workers were divided into five groups based on the HRCT scoring: pleural disease (N=190), pulmonary fibrosis (N=68), emphysema (N=148), combined fibrosis and emphysema (N=74), and marked adhesions (N=110). The graded lung function impairment was compared between the groups. RESULTS: Moderate impairment of forced expiratory volume in 1 second [odds ratio (OR) 2.72, 95% confidence interval (95% CI) 1.31-5.57] and forced vital capacity (OR 2.81, 95% CI 1.05-6.89) was associated with the persons with combined fibrosis and emphysema. Marked impairment of diffusing capacity was associated with the combined fibrosis and emphysema (OR 4.94, 95% CI 2.48-9.77) but not with pleural disease (OR 0.21, 95% CI 0.09-0.45) or pulmonary fibrosis (OR 0.36, 95% CI 0.08-1.05). For the persons with combined fibrosis and emphysema, the mean fibrosis score did not differ between normal, slightly reduced, or markedly reduced diffusing capacity, but the emphysema score was significantly higher for the patients with marked impairment than for those with normal diffusing capacity (P < 0.01). CONCLUSIONS: Different profiles of asbestos- and smoking-induced pulmonary or pleural disease were found. The results indicate that the most important factor determining the degree of functional impairment in smoking asbestos-exposed workers is the presence of pulmonary emphysema.  相似文献   
105.
To study the relation between sodium transport in airway epithelium and postnatal pulmonary adaptation, we measured nasal potential difference at 1 to 4 hours and lung compliance at 21 to 48 hours after birth in 20 healthy infants. Sodium transport correlated with lung compliance ( r 2 = 0.40, P < .003). Airway sodium transport plays a role in postnatal pulmonary adaptation.  相似文献   
106.
OBJECTIVE: Increased numbers of mast cells (MCs) are present in ruptured coronary plaques, suggesting to play a role in acute coronary syndromes. We evaluated the distribution densities of MCs, macrophages and T cells in carotid plaques and correlated these findings to stroke risk factors as well as history of stroke or TIA. METHODS AND RESULTS: Seventy-eight carotid samples from 75 patients (16 plaques from asymptomatic patients and 62 from patients with recent ischemic symptoms) undergoing carotid endarterectomy with an internal carotid stenosis >70% that were immunostained and quantified for MCs, macrophages and T cells. The MC distribution density showed positive correlation with the degree of carotid stenosis (p = 0.012), serum levels of total cholesterol (p = 0.021), LDL cholesterol (p = 0.013) and triglycerides (p = 0.005), and an inverse correlation with serum HDL cholesterol levels (p = 0.001). The average MC density (p = 0.023), but not the macrophage (p = 0.58) or T cell (p = 0.74) density, was higher in the symptomatic than in the asymptomatic patients. In a comparison of plaques ipsilateral and contralateral to the thromboembolic event, the densities of the three types of inflammatory cells were similar. CONCLUSIONS: Increased MC distribution density is associated with an atherogenic serum lipid profile, high-grade carotid artery stenosis and symptomatic carotid artery disease. These findings suggest a potential involvement of MCs in the pathophysiology of carotid artery stenosis.  相似文献   
107.
BACKGROUND: Alcohol dehydrogenases (ADHs) may be involved in the pathogenesis of neurodegenerative disorders because of their multiple roles in detoxification pathways and retinoic acid synthesis. In a previous study, significant association of an ADH class IV allele with Parkinson disease (PD) was found in a Swedish sample. PATIENTS: The previously associated single-nucleotide polymorphism plus 12 further polymorphisms in the ADH cluster on human chromosome 4q23 were screened for association in an extension of the original sample that now included 123 Swedish PD patients and 127 geographically matched control subjects. A rare nonsense single-nucleotide polymorphism in ADH1C (G78stop, rs283413) was identified in 3 of these patients but in no controls. To obtain sufficient power to detect a possible association of this rare variant with disease, we screened a large international sample of 1076 PD patients of European ancestry and 940 matched controls. RESULTS: The previously identified association with an ADH class IV allele remained significant (P<.02) in the extended Swedish study. Furthermore, in the international collaboration, the G78stop mutation in ADH1C was found in 22 (2.0%) of the PD patients but only in 6 controls (0.6%). This association was statistically significant (chi(2)(1) = 7.5; 2-sided P = .007; odds ratio, 3.25 [95% confidence interval, 1.31-8.05]). In addition, the G78stop mutation was identified in 4 (10.0%) of 40 Caucasian index cases with PD with mainly hereditary forms of the disorder. CONCLUSION: Findings presented herein provide further evidence for mutations in genes encoding ADHs as genetic risk factors for PD.  相似文献   
108.
In adults, HLA haplotype B8-DRB1*03 is clearly associated with a severe clinical course of nephropathia epidemica caused by Puumala hantavirus. We investigated whether the same applies in pediatric patients. This HLA haplotype was found in 20 of 39 (51%) of the patients, a significantly higher figure than in the Finnish population (19%). There were, however, no significant differences in the clinical picture between patients with and without HLA B8-DRB1*03.  相似文献   
109.
110.
PURPOSE: The purpose of this study was to characterize the diagnostic performance of a regimen of CT screening for lung cancer. METHODS: Using a common protocol/regimen of screening, 2968 asymptomatic persons at high risk for lung cancer were enrolled in two studies [Early Lung Cancer Action Projects (ELCAP) I and II] for baseline and annual repeat screening. A total of 4538 annual repeat screenings were performed. The regimen's diagnostic performance was characterized in terms of frequency of positive result of the initial CT as well as of screen-diagnosis and Stage I screen-diagnosis among all diagnoses (interim-diagnoses included), all separately for baseline and annual repeat screenings. RESULTS: The proportions with positive result of the initial CT were 12% and 6% in the baseline and repeat screenings, respectively. The proportions of screen-diagnoses among all diagnoses (interim-diagnoses included) were 97% and 99% in the baseline and repeat cycles, respectively. The corresponding proportions of pre-surgical Stage I screen-diagnoses were 95% and 93%. CONCLUSION: The performance of the ELCAP regimen is quite satisfactory in avoiding over many positive results of the initial CT, and it produces highly promising diagnostic results as for the attainment of cure by early intervention.  相似文献   
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