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1.
The purpose of this longitudinal investigation was to study changes in the dental arches and dentition that occur in midadulthood in an untreated, normal sample. The subjects had Class I molar and canine relationships with less than 4.0 mm of overjet and less than 50% overbite. None had undergone previous orthodontic treatment. Evaluations and measurements were made from dental casts and periapical radiographic surveys of 15 females and 15 males from approximately 25 years to 46 years. The findings indicate that over the span of the study, significant changes occur in the maxillary and mandibular dental arches and dentition in both males and females, including a clinically significant increase in tooth size-arch length (circumference) discrepancy. These changes should be considered part of the normal maturational process and should be taken into consideration when planning treatment and retention options for adolescent and adult patients. 相似文献
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A 4-year cephalometric study was conducted on 14 wearers of complete dentures to quantify the anterior alveolar bone loss and to study any associated changes in the maxillomandibular relationships. Both the occlusal and the rest-face heights underwent a significant decrease while a parallel tendency for anterior rotation was recorded. The continuous bone loss in the anterior mandible had a significant relationship to the reduction of the anterior face height. 相似文献
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The assessment of blood pressure in children and adolescents is of great importance in order to gain a better understanding of its pattern of evolution. The authors publish the normal values of blood pressure in Portuguese children and adolescents, according to age and sex, as well as the mean values of the 90th percentile, which are very important to separate normal children from those with high blood pressure. In this study the fifth Korotkoof sound is used to define diastolic blood pressure in all ages. New blood pressure tables are also published, for children and adolescents, that now include the height percentile for age and blood pressure. These new charts have been developed to guide practising clinicians in antihypertensive drug therapy, when indicated. 相似文献
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Passive smoking is a major health risk in young children. We investigated the percentage of children with mothers and/or fathers who reported regular smoking. Data are the national and regional health surveys of the German Cardiovascular Prevention Study (GCP) conducted from 1984 to 1992 in West Germany. 2538 mothers aged 25-40 years were included. The prevalence of passive smoking in children due to smoking mothers was 33.6% 55.4% of the children up to 5 years lived in households with at least one smoking parent member. In 23.4% of these households both parents were smokers. If only one member of the parents smoked this was in two out of three cases the father. 28.2% of mothers with a child younger than one year were current smokers. This prevalence rate increased with the age of the youngest child up to 35.6% for mothers, whose youngest child was 5 years old. Multiple logistic regression analysis was performed to investigate the association between smoking behaviour and the following variables: mother's age, social class, family status, community size and year of the survey. It was found that lower social class members, unmarried or divorced mothers and inhabitants of large cities reported significantly more often regular current smoking. These results underscore the importance of special intervention programs to reduce smoking in parents with young children. 相似文献
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This study was performed to determine whether stimulation of the carotid chemoreceptors increases total or regional cerebral blood flow and whether activation of arterial chemoreceptors contributes to cerebral vasodilation during systemic hypoxemia. In anesthetized and ventilated dogs, carotid chemoreceptors were stimulated with nicotine or hypoxic and hypercapnic blood. To measure total and regional cerebral blood flow, we used labeled 15-mu microspheres. Stimulation of chemoreceptors did not increase cerebral blood flow or produce significant redistribution of cerebral blood flow, even though the chemoreflex was intact in these animals (as manifested by vasoconstriction in muscle, kidney, and small bowel) and the cerebral vessels dilated in response to systemic hypercapnia. In other studies in anesthetized, ventilated dogs and rhesus monkeys, cerebral vasodilator responses to systemic hypoxemia were observed before and after denervation of carotid and aortic chemoreceptors. Systemic hypoxemia produced large and equivalent increases in cerebral blood flow before and after chemodenervation. We conclude that stimulation of carotid chemoreceptors does not produce cerebral vasodilation and that chemoreceptors do not contribute significantly to cerebral vasodilation during systemic hypoxemia. 相似文献
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Maxillary and mandibular molar and incisor vertical dimensions were evaluated in subjects who had excessive, normal, and short lower anterior face height in relation to upper face height. Sexual dimorphism was also investigated. The dentoalveolar heights were compared between Class I and Class II, dental and skeletal malocclusions. The sample was drawn from the Burlington Growth Centre sample and consisted of 188 male and 156 female subjects at age 12 years, for whom lateral head films were available. This sample was classified into excessive, normal, and short lower anterior face height, using the ratio upper anterior face height/lower anterior face height (UAFH/LAFH). The results showed that the dentoalveolar heights are significantly different between faces with excessive, normal, and short lower anterior face heights, except for the lower posterior dental height, which showed no difference between short and normal lower anterior face height subjects. All dentoalveolar heights are larger for male subjects except for the upper posterior dental height. Dentoalveolar heights are similar between Class I and Class II dental and skeletal malocclusions. The upper teeth present a higher correlation to the UAFH/LAFH ratio than the lower teeth. Stepwise regression analysis shows that 22% of the variation in the ratio is explained by the maxillary and mandibular molars and 41% is explained by the maxillary and mandibular incisors. 相似文献
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F Farinati S Formentini G Della Libera F Valiante MC Fanton F Di Mario F Vianello A Pilotto R Naccarato 《Canadian Metallurgical Quarterly》1993,39(3):146-151
Whether or not the gastric mucosa undergoes significant changes in normal aging subjects is still open to debate. In 51 subjects undergoing endoscopy and lacking any significant endoscopic or histologic modification we evaluated mucosal thickness, gland number, numbers of parietal, chief and mucous cells at the fundus and of mucopeptic cells at the antrum, with a morphometric method, subgrouping the patients according to their age class. Our findings demonstrate that the number of parietal cells tends to increase with age and, on the other hand, the number of mucous cells is reduced in elderly subjects (p < 0.05). When considering the parietal-to-mucous cell ratio, this is significantly increased (p = 0.0005) with age. Acid secretion being an offensive factor and mucus a fundamental component of the gastric mucosal barrier, these findings suggest an increased susceptibility of the gastric mucosa to damage in the elderly. 相似文献
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The study is based on an anthropometric assessment of X-ray films obtained in two series of males with complete unilateral cleft lip and palate. The first series was examined at the age of 5, 10 and 15 years, the second series at 15 and 20 years. The films were assessed with Jarabak's analysis. The aim of our study was to compare the amount of growth and character of developmental changes in the prepubertal, pubertal and postpubertal period of life. The highest growth rate of skeletal structures was present in the prepubertal period, it was somewhat slighter in the pubertal period and it still continued in the postpubertal period. The high growth rate in the prepubertal period was probably related to the eruption of permanent teeth. In spite of a marked deterioration of sagittal jaw relations during the prepubertal period an improvement of an overjet was attained. However during the puberty and the postpubertal period a further improvement was not recorded. The results are in agreement with facial type of growth characterized by a slight pubertal spurt. 相似文献
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TM H?ltt? KA R?nnholm H Jalanko M Ala-Houhala M Antikainen C Holmberg 《Canadian Metallurgical Quarterly》1997,17(6):573-580
The aim of this study was to examine the effect of intensive practice in table tennis on perceptual coincident timing. The main question was whether the perceptual demands encountered in fast ball sports produce modifications of the perceptual visual system. Expert table tennis players and novices were compared in a perceptual task which consisted of estimating, by pressing a key, the arrival of a moving stimulus at a target. The stimulus, which was presented either at constant velocity or at constant deceleration, reproduced as closely as possible the natural visual demands encountered in table tennis. The difference between the time of response and the time of arrival of the stimulus at a target position was measured over 40 trials for each of the 16 participants. The results showed no effect of expertise under the constant-velocity condition but an effect under the decelerative condition, indicating that experts were less trajectory-dependent than novices. This result was interpreted as reflecting a better adaptation of the perceptual system of experts to the constraints encountered during table tennis and specifically to the perceptual demands resulting from varied and decelerated ball trajectories. Finally, some limitations of the coincidence anticipation procedure are highlighted, concerning its use in practical settings for evaluating athletes or detecting sport talents, and the need for the simulation conditions during testing to reproduce as closely as possible the perceptual demands of real life is discussed. 相似文献
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O Rico Cordeiro JR Bravo González M Díaz González 《Canadian Metallurgical Quarterly》1994,46(2):94-98
The effectiveness or post-license efficacy of the BC antimeningococcal vaccine (VA-MENGOC-BC) was assessed 1 year after the end of the immunization campaign in children aged 0 to 5 years. Occurrence of the disease before and after intervention is described and effectiveness is estimated following the recommendations described by Orenstein et al. We used 2 case definitions to compare results in groups formed following different criteria, according to the employed diagnostic tests. Two formulas are used to assess efficacy: one, estimating the rates among vaccinated and non-vaccinated; and the other one, estimating the ratio of cases per vaccinated population. The increase of the relative annual decrease of the incidence occurring since 1985--a decrease of 10% or less--which in 1990 reached 34.6% should be stressed; the ratio of new cases prevented by the intervention was higher than 75%. Effectiveness or post-license efficacy was close to 90%, independently from the case definition variant or formula employed. 相似文献
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We analysed the results of oocyte donation to women of advanced reproductive age (> or = 45 years old) and followed their pregnancies through to delivery in order to assess obstetrical outcomes. Patients (n = 162) aged 45-59 years (mean +/- SD; 47.3 +/- 3.4 years) underwent 218 consecutive attempts to achieve pregnancy. Oocytes (16.2 +/- 7.2 per retrieval) were provided by donors < or = 35 years old. Cleaving embryos (8.2 +/- 4.8 zygotes/couple) were transferred transcervically (4.5 +/- 1.1 per embryo transfer) to recipients prescribed oral micronized oestradiol and intramuscular progesterone. Following oocyte aspiration there were six instances of non-fertilization (2.8%) and 212 embryo transfers. A total of 103 pregnancies was established for an overall pregnancy rate (PR) of 48.6%, which included 17 preclinical pregnancies, 12 spontaneous abortions, and 74 delivered pregnancies (clinical PR 40.6%; delivered PR 34.9%). Multiple gestations were frequent (n = 29; 39.2% of pregnancies) and included 20 twins, seven triplets, and two quadruplets. Two of the triplet and both of the quadruplet pregnancies underwent selective reduction to twins. Antenatal complications occurred in 28 women (37.8% of deliveries) and included preterm labour (n = 9), gestational hypertension (n = 8), gestational diabetes (n = 6), carpel tunnel syndrome (n = 2), pre-eclampsia (n = 2), HELLP syndrome (n = 2), and fetal growth retardation (n = 2). 48 (64.8%) deliveries were by Caesarean section. The gestational age at delivery for singletons was 38.3 +/- 1.3 weeks (range 35-41 weeks), with birth weight 3218 +/- 513 g (range 1870-4775 g); twins 35.9 +/- 2.0 weeks (range 32-39 weeks), birth weight 2558 +/- 497 g (range 1700-3450 g); and triplets 33.5 +/- 0.7 weeks (range 32-34 weeks), birth weight 1775 +/- 190 g (range 1550-2100 g). Neonatal complications (4.6% of babies born) included growth retardation (n = 2), trisomy 21 (n = 1), ventricular septal defect (n = 1), and small bowel obstruction (n = 1). There were no maternal or neonatal deaths. We conclude that oocyte donation to women of advanced reproductive age is highly successful in establishing pregnancy. However, despite careful antenatal screening, obstetrical complications are common, often secondary to multiple gestation. 相似文献
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Bernstein Daniel M.; Erdfelder Edgar; Meltzoff Andrew N.; Peria William; Loftus Geoffrey R. 《Canadian Metallurgical Quarterly》2011,37(2):378
[Correction Notice: An erratum for this article was reported in Vol 37(3) of Journal of Experimental Psychology: Learning, Memory, and Cognition (see record 2011-08992-005). On page 381, the notation in Figure 1 is incorrect. The corrected notations are discussed in the correction.] Upon learning the outcome to a problem, people tend to believe that they knew it all along (hindsight bias). Here, we report the first study to trace the development of hindsight bias across the life span. One hundred ninety-four participants aged 3 to 95 years completed 3 tasks designed to measure visual and verbal hindsight bias. All age groups demonstrated hindsight bias on all 3 tasks; however, preschoolers and older adults exhibited more bias than older children and younger adults. Multinomial processing tree analyses of these data revealed that preschoolers' enhanced hindsight bias resulted from them substituting the correct answer for their original answer in their recall (a qualitative error). Conversely, older adults' enhanced hindsight bias resulted from them forgetting their original answer and recalling an answer closer to, but not equal to, the correct answer (a quantitative error). We discuss these findings in relation to mechanisms of memory, perspective taking, theory of mind, and executive function. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
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LG Lastra-Escudero SG Roldán-Fernández E Hernández-Martínez AP Hernández-Torres FG Lechuga-Padrón 《Canadian Metallurgical Quarterly》1998,40(5):408-414
AIMS: Abdominal aortic aneurysms are characterised by changes in the extracellular matrix of the arterial media, in particular a reduction in elastin concentration. These changes are mediated by increased levels of endogenous matrix metalloproteinases (MMPs). Recently, calcium channel blockers have been shown to increase the proteolytic activity of MMP-2 secreted by vascular smooth muscle cells. It may therefore by hypothesised that calcium antagonists may potentiate the activity of MMPs in aneurysmal disease and thus accelerate AAA expansion. In this study, the ability of amlodipine--a calcium antagonist--to influence elastin degradation, was assessed in a previously described model of aneurysmal disease. METHODS: Porcine aortic segments (n = 8) were pre-incubated in exogenous pancreatic elastase for 24 h prior to culture in standard conditions for 6 days with 10 and 100 micrograms/l amlodipine. Control segments were cultured both with and without amlodipine and without elastase. At the termination of culture MMPs were extracted from the tissue and quantified by a combination of substrate gel enzymography and immunoblotting. The volume fractions of elastin and collagen were determined by stereological analysis of EVG stained sections. RESULTS: Gel enzymography demonstrated significantly increased MMP-9 activity in the amlodipine treated segments, median 4.218 vs. 2.809 arbitrary units (p < 0.01) and this elevated activity was reflected in a significant destruction of medial elastin 27.0 vs. 40.5% (p < 0.05). CONCLUSION: Therapeutic ranges of amlodipine significantly enhanced elastin degradation and potentiated MMP-9 activity within the aortic organ cultures. 相似文献
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F De Luca M Maghnie T Arrigo F Lombardo MF Messina S Bernasconi 《Canadian Metallurgical Quarterly》1996,85(10):1167-1171
Thirteen growth hormone deficient infants underwent substitutive treatment for a least 9 years, since less than 5 years of age until adulthood. They presented with average growth failure reaching 4.1 SDS and attained an adult mean height close to target height. In eight subjects final height exceeded the respective target height and only three patients failed to achieve an end height within the target range. The analysis of the factors conditioning ultimate stature pointed out that height outcome correlated negatively with chronological age at therapy initiation and positively with height at puberty onset. It is concluded that full catch-up growth to target percentile is possible in growth hormone-deficient children, provided that substitutive treatment is begun within the 5 years of life. This conclusion is substantiated for the first time by data on end stature. 相似文献
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Malec James F.; Smith Glenn E.; Ivnik Robert J.; Petersen Ronald C.; Tangalos Eric G. 《Canadian Metallurgical Quarterly》1996,10(1):66
The ability of clusters of psychometric profiles to predict cognitive decline 3 to 5 years later was examined. Using Ward's method, researchers conducted cluster analysis of age- and education-corrected Mayo Cognitive Factor Scale (MCFS) scores obtained at first evaluation for 376 normal elderly. Results revealed 4 of 16 cluster profiles were predicted to represent at-risk status for future cognitive decline; 258 of the original sample completed psychometric reassessment. Membership in an at-risk cluster did not powerfully predict subsequent medical evaluation of cognitive or psychiatric disorder or status as lost to follow-up. Repeated measures analyses of variance of MCFS scores showed no differential decline in learning or memory between normal and at-risk clusters. Thus, in a nonclinical sample, relative cognitive impairments are not powerfully predictive of future cognitive decline. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献