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31.
Objective:  Hutchinson-Gilford progeria syndrome (HGPS) is a rare early-onset accelerated senescence syndrome. In HGPS, a recently identified de novo dominant mutation of the lamin A gene ( LMNA ) produces abnormal lamin A, resulting in compromised nuclear membrane integrity. Clinical features include sclerotic skin, cardiovascular and bone abnormalities, and marked growth retardation. Craniofacial features include 'bird-like' facies, alopecia, craniofacial disproportion, and dental crowding. Our prospective study describes dental, oral soft tissue, and craniofacial bone features in HGPS.
Methods:  Fifteen patients with confirmed p.G608G LMNA mutation (1–17 years, seven males, eight females) received comprehensive oral evaluations. Anomalies of oral soft tissue, gnathic bones, and dentition were identified.
Results:  Radiographic findings included hypodontia ( n  = 7), dysmorphic teeth ( n  = 5), steep mandibular angles ( n  = 11), and thin basal bone ( n  = 11). Soft tissue findings included ogival palatal arch ( n  = 8), median sagittal palatal fissure ( n  = 7), and ankyloglossia ( n  = 7). Calculated dental ages (9 months to 11 years 2 months) were significantly lower than chronological ages (1 year 6 months to 17 years 8 months) ( P  = 0.002). Eleven children manifested a shorter mandibular body, anterior/posterior cranial base and ramus, but a larger gonial angle, compared to age/gender/race norms.
Conclusion:  Novel oral-craniofacial phenotypes and quantification of previously reported features are presented. Our findings expand the HGPS phenotype and provide additional insight into the complex pathogenesis of HGPS.  相似文献   
32.
AIM: To analyze the effect of age-period and birth cohort on gastric cancer mortality, in Brazil and across its five geographic regions, by sex, in the population over 20 years of age, as well as make projections for the period 2010-2029.METHODS: An ecological study is presented herein,which distributed gastric cancer-related deaths in Brazil and its geographic regions. The effects of ageperiod and birth cohort were calculated by the Poisson regression model and projections were made with the age-period-cohort model in the statistical program R. RESULTS: Progressive reduction of mortality rates was observed in the 1980's, and then higher and lower mortality rates were verified in the 2000's, for both sexes, in Brazil and for the South, Southeast and Midwest regions. A progressive decrease in mortality rates was observed for the Northeast(both sexes) and North(men only) regions within the period 1995-1999, followed by rising rates. CONCLUSION: Regional differences were demonstrated in the mortality rates for gastric cancer in Brazil, and the least developed regions of the country will present increases in projected mortality rates.  相似文献   
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Aim: To describe cardiorespiratory fitness and body mass index (BMI) values in a representative population of 9-year-old Norwegian children in two rural communities and compare present values with previous findings.
Methods: Two hundred and fifty-nine 9-year-old children were invited, and 256 participated in this study. Maximal oxygen uptake was directly measured during a continuous progressive treadmill protocol. Body mass and height were also measured.
Results: The mean ± SD relative maximal oxygen uptake was 52.8 ± 6.5 for boys and 46.9 ± 7.2 mL/kg/min for girls. Eight percent of the boys and 16.8% of the girls were classified as overweight, and 1.6% of the boys and 6.9% of the girls as obese. Mean age, body mass, height and Ponderal index were not significantly different between sexes. Girls had a higher BMI than boys (p = 0.05).
Conclusion: Compared to earlier Norwegian studies, children's BMI values seem to have increased substantially. This increase is most pronounced in girls. When assessing these differences using the PI, this increase is less marked. Comparing maximal oxygen uptake data with that in earlier Nordic studies, there is no evidence that fitness has declined among 9-year olds. However, the limitations of the few earlier studies make reliable comparisons difficult.  相似文献   
36.
We attempted to evaluate the role of maternal hyperphenylalaninaemia (HPA) as an isolated cause of mental retardation and microcephaly in children. This transversal study observed the plasma phenylalanine from mothers of 161 children with mental retardation and/or microcephaly of unknown origin. In this sample, we found two women with previously undiagnosed HPA, a frequency (2/161) higher than expected for our general population (1:12 500) ( p < 0.001). We concluded that the plasma phenylalanine levels should be determined during preconceptional evaluation of every woman of reproductive age that already has had a child affected either by mental retardation or microcephaly of unknown cause. It is particularly significant where women currently having their pregnancies have not been screened for phenylketonuria as newborns, as happens in most developing countries.  相似文献   
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To evaluate embryonic and endometrial factors for their value in predicting pregnancy outcome in in-vitro fertilization (IVF) and embryo transfer, a retrospective data collection and prospective uterine artery colour Doppler imaging study was performed in a university-based IVF-embryo transfer programme setting. A total of 210 patients were included and grouped as follows: (I) IVF with controlled ovarian stimulation (214 cycles); (II) frozen-thaw cycle of autologous embryos (30 cycles); (III) oocyte donation, no cryopreservation (12 cycles); (IV) frozen-thaw cycle with embryos from donated oocytes (10 cycles). Embryo quality was significantly better in pregnant than non-pregnant cycles (group I, P = 0.0104; groups II-IV, P = 0.0418). The endometrial echo was significantly thicker in pregnant versus non-pregnant patients in group I (P = 0.0059), but not in groups II-IV (P = 0.741). Past uterine surgery or abnormalities had no effect on pregnancy outcome. There were no significant differences in mean uterine artery resistance index or peak systolic velocity in pregnant versus non-pregnant patients in groups II-IV. Thus, embryo quality is the most reliable predictor of pregnancy outcome. Endometrial measurements were significantly thicker in subsequently pregnant patients only in group I, where the endometrium reflects the hormonal environment. Doppler parameters were not useful in predicting pregnancy outcome.   相似文献   
39.
亮菌甲素速溶片剂的研制及其利胆作用研究   总被引:1,自引:0,他引:1  
试制出亮菌甲素速溶片剂(A),并以市售品亮菌甲素片剂(B)、亮菌甲素粉针(C)等作对照,考察了它们对大鼠体内胆汁分泌作用的影响,并测定了A和B的体外溶出速率。结果表明,A片剂比B片剂明显地增强了利胆作用,A片的体外溶出速率也较B片为快。  相似文献   
40.
番荔枝种子化学成分研究   总被引:9,自引:2,他引:9  
从番荔枝Annona squamosa L.种子的乙醇提取物分得三个polyketide类化合物:squamostatin-8(Ⅰ),annonin-vl(Ⅱ)和desacetyluvaricin(Ⅲ)以及胡萝卜甙(daucosterol,IV)。其中Ⅰ是一种新的polyketide,经光谱解析方法,测定了Ⅰ的化学结构式和部分碳原子的立体化学.  相似文献   
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