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61.
There is no published data about associations between the state of dentition and bone mass in adolescents. The objective of this study was to investigate whether the prevalence of caries and dental malocclusion is associated with bone mass during growth. In 123 healthy Caucasian subjects (72 males, 51 females) aged 14-18 yr, DMFT figures (decayed teeth, missing teeth, filled teeth) and presence of malocclusion, according to Angle classification, were determined. Participants completed a questionnaire regarding dental hygiene, physical activity level, and consumption of sweets. Anthropometry and pubertal stages were examined. Bone mineral density (BMD) was examined using dual energy X-ray absorptiometry (DXA) in the total body, head, and lumbar spine. No association was found between DMFT (mean+/-SD: 8.33+/-3.9) and BMD or Z-scores for BMD. Malocclusion was found in 49 subjects (39.8%) and was more prevalent in females than males. Malocclusion was associated with lower total BMD independently of body size (p=0.001; Z-scores: -0.21+/-0.27 vs +0.33+/-0.17; p=0.1) in males (but not females), producing odds ratio 1.6 (95% confidence interval: 1.09-2.34%; p=0.02). Head BMD was also lower in the males with malocclusion than in those without (p=0.004). Neither caries nor the tooth loss appear to be associated with BMD during growth. Boys with malocclusion are at higher risk of reduced BMD. This suggests that inadequate bone mass accrual in males coexists with impaired growth of the masticatory system in childhood and adolescence, however, the causal pathway is unknown. Factors that produce malocclusion may also affect bone mass or size but further prospective studies are needed to evaluate the relationship.  相似文献   
62.
To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bone-specific alkaline phosphatase, markers of bone turnover, was seen during pregnancy ( p < 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients ( p < 0.05). TB BMD was positively correlated with LS BMD (r2 = 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied.  相似文献   
63.
64.
We found multimolecular antigenic mimicry of arthritogenic autoantigens and peptides from several other “self” or foreign antigens sharing amino acid sequence homologies. Many of these new mimotopes induced arthritis and/or uveitis upon immunization in Lewis rats, indicating a role for multiple antigens in the initiation of a certain autoimmune disease.  相似文献   
65.
During May 1986, a survey to assess the frequency of allergic disorders was conducted among primary school children of Alghero, Sardinia, using a structured self-administered questionnaire. The following problems were investigated: allergic conjunctivitis, asthma, wheezing, allergic rhinitis, urticaria and eczema. Of the original 1823 questionnaires distributed, 1961 (92.8%) were completed by parents and returned. Overall, 238 children (14.1%) were reported to have shown at least one episode of one or more of the above and were regarded as 'allergic'. Among the potential risk factors investigated, statistically significant differences (P less than 0.05) between allergic and non-allergic children were only found for history of allergy in at least one parent (odds ratio, OR = 2.2) and exposure to passive smoking (OR = 1.4).  相似文献   
66.
Monoamine oxidase A gene promoter (MAOA-uVNTR) and catechol-O-methyltransferase V158M (COMT-V158M) gene functional polymorphisms are reported to be associated with impulsive-aggression, but a biological intermediate effect remains to be determined. This study assessed the association of these polymorphisms with cerebrospinal fluid (CSF) monoamine metabolites as endophenotypes. Ninety-eight Caucasian psychiatric subjects were assessed for Axis I and II diagnosis. Subjects were genotyped for the functional polymorphisms, MAOA-uVNTR and COMT-V158M. CSF was obtained by lumbar puncture. Relationships of the two polymorphism to monoamine metabolites: HVA, 5-HIAA, and MHPG were examined. The higher-expressing MAOA-uVNTR genotype was associated with higher CSF-HVA levels in males only (n = 46) (195.80 pmol/ml, SD = 61.64 vs. 161.13, SD = 50.23, respectively; P = 0.042). No association was found with diagnosis. COMT-V158M had no association with CSF monoamine metabolites. The association of MAOA-uVNTR with dopaminergic activity in males is a preliminary finding that needs to be replicated in a larger sample of Caucasian males and relationships sought with clinical phenotypes. This article contains supplementary material, which may be viewed at the American Journal of Medical Genetics website at http://www.interscience.wiley.com/jpages/0148-7299:1/suppmat/index.html.  相似文献   
67.
Research on physical activity (PA) by level of acculturation in Hispanic children is limited and findings have been mixed. We examined PA participation by primary language used with parents in a representative sample of 4th, 8th, and 11th grade Texas public school students. Mixed-effects regression models were conducted using cross-sectional data from the 2004–2005 School Physical Activity and Nutrition Study (n = 22,049). Self-reported PA was compared among three language-ethnic groups: Spanish-Hispanic (SH) (referent); English-Hispanic (EH); and English-Other (EO). EH and/or EO girls were generally between 1.25 and 2.58 [OR] times more likely to participate in PA across grade levels, with the largest differences found for school sports in 8th grade girls. EH and EO 8th grade boys were 1.71 (CI: 1.40, 2.10) and 2.06 (CI: 1.68, 2.51) times, respectively, more likely to participate in school sports. Findings indicate important disparities in Spanish-speaking Hispanic children’s PA participation.  相似文献   
68.

Background  

Anterior cruciate ligament (ACL) injury or reconstruction can cause knee impairments and disability. Knee impairments are related to quadriceps performance – accelerated reaction time (ART) – and disability to performance of daily living activities which is assessed by questionnaires such as the Lysholm knee score. The purposes of this study were to investigate the effect of cross exercise, as supplementary rehabilitation to the early phase of ACL reconstruction: a) on quadriceps ART at the angles 45°, 60° and 90° of knee flexion and, b) on the subjective scores of disability in ACL reconstructed patients.  相似文献   
69.
The possible effect of Government Consumption (a component of Gross Domestic Product (GDP)) on attainment of the hunger Millennium Development Goal (MDG1) was analyzed by evaluating the effect of macroeconomic, social, demographic and policy variables on average undernourished population. Eighty-four developing countries with data available on undernourished population were included in an ecological study. Regression models were applied to explore possible determinants of Undernourished between 1990 and 2004 and consequent achievement of the projected 2004 MDG1. In 2004, 1.4% of the overall undernourished population in the studied countries [70.16 million people] was in excess of the projected level required to meet MDG1. The multiple linear regression showed significant associations between Undernourished and poverty levels, the Gini Index, rural population and Government Consumption. The multiple logistic regression showed significant associations between achievement of projected 2004 MDG1 levels and Government Consumption and the Gini Index. The significant associations between Undernourished and Government Consumption suggest that the effects of GDP components on social conditions call for more thorough research and that policymakers such as governments and international financial institutions need to ensure that changes in distributive and redistributive policies do not negatively affect the possibility of achieving MDG1.  相似文献   
70.
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