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1.
Abstract— Biomedical determinants of dental caries have been more extensively investigated than psychosocial factors and their impact on caries prevalence and incidence seems to be greater. However, a majority of these investigations relate to children and adolescents. An implementation of social and psychologic variables may be more relevant regarding dental caries in adults. In addition, a multidisciplinary approach might improve our understanding of dental caries as a multifactorial disease and bridge the gap between a biomedical concept and a more holistic approach to dental health.  相似文献   
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A decrease in ostial pulmonary vein (PV) diameter was observed in patients on the day after radiofrequency ablation of atrial fibrillation (AF). This study examined whether a relative reduction in PV diameter on day 1 (RRPVD1) after the procedure predicts the late development of severe PV stenosis (PVS). The study included 104 consecutive patients (mean age = 55 years, range 46–61, 34 women) with drug refractory AF. Pulmonary vein diameter was measured using MR angiography (MRA) on the day before and on day 1 after the ablation procedure. The MRA was repeated every 3 months after the procedure. Severe PVS was defined as a >70% diameter reduction from the initial ostial diameter. The cut-off of RRPVD1 was prespecified as 25% decrease in initial diameter. The data are presented as medians and interquartile range. A total of 357 PV were treated. The RRPVD1 was 0.0% (0.0–11.1%). Severe PVS was found in 18 PV during a follow-up of 12 months (range 6–13). The log-rank analysis confirmed a strong association between a RRPVD1 ≥25% and the development of PVS (hazard ratio: 7.1; 95% confidence interval 3.8–13.5, P < 0.0001). By multivariate Cox regression model, after adjustment of procedure variables, RRPVD1 was the strongest predictor of development of severe PVS. RRPVD1 ≥25% was a strong independent predictor of development of severe PVS.  相似文献   
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On the Orientation of the HL-A Region and the PGM3 Locus in the Chromosome   总被引:1,自引:0,他引:1  
A study of four families with a cross-over within the HL—A region and in which the crossover parent is heterozygous at PGM3 indicates with a probability of about 95% that the chromosomal orientation of the three linked loci is LA · FOUR · PGM3.  相似文献   
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abstract – Groups of white albino rats were used in this study. Serial sections were prepared of the hard and soft palate, tongue, cheek, gingiva, cornea and ear, and were stained with hematoxylin and eosin. Mitotic counts in tongue epithelium of nine groups of rats which received various colchicine dosages (0 to 3 mg/kg body weight) and were sacrificed 3½ h later showed that 1 mg colchicine per kg body weight is the optimal dosage for studying the mitotic activity in rat oral epithelium. Mitotic counts in six other groups of rats sacrificed at different times (0 to 50 min) after the administration of colchicine indicated that the colchicine takes effect 25–30 min after the injection. The pattern of diurnal variation in mitotic activity was determined in the ear and various oral epithelia using eight groups of colchicinized rats. A fairly high correlation was found between the daily mitotic rates and the mitotic rates obtained during the maximum mitotic activity. There was a low correlation between the daily mitotic rates and turnover times indicating that calculations of turnover time may fail to express the mitotic activity of the epithelium. Mitotic counts for various sites of the hard palate, tongue and cheek in seven rats indicated that the mitotic activity may vary from one region to another within the individual tissue.  相似文献   
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ABSTRACT. The value of M-mode echocardiography in assessment of left ventricular (LV) function in patients with aortic regurgitation due to aortic valve endocarditis (AVE) was studied in 12 consecutive patients and compared with the findings in 30 patients with chronic aortic regurgitation (CAR). Patients with AVE had markedly increased LV end-diastolic and end-systolic diameters, whereas fractional shortening was normal. A linear correlation was found between the LV ejection fractions calculated by echocardiography and angiography, but echocardiography markedly overestimated the ejection fractions. There was a close linear correlation between the prematurity of mitral valve closure (MVC) and LV end-diastolic pressure. Patients with CAR had lower end-diastolic pressure, similarly increased LV internal diameters and none had premature MVC. Thus, M-mode echocardiography can identify patients with premature MVC and high LV filling pressure. However, echocardiographic LV function indices based on measurement of internal dimensions overestimate the LV function and these data should be interpreted with caution.  相似文献   
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