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1.
Since the end of the 2nd World War, Japan has seen quite rapid socioeconomical development. With this development the physical size of Japanese children has increased, but the final size, especially the stature, is still shorter than that of Americans or Europeans. Bone maturation velocities were compared among Japanese and Chinese children and adolescents aged 7 to 18 (in 1986) and English TW2-subjects, using the TW2 method. Asian children and adolescents may have a different tempo of skeletal maturation during pubertal growth from that of English children and adolescents. This, probably genetic, difference in the tempo of skeletal maturation, especially that of RUS, between Japanese and English during pubertal growth may be one of the main causes of the final difference in the stature of the two groups.  相似文献   
2.
The adnexal torsion is an uncommon gynaecological emergency; however, it must be excluded in young girls in order to conserve their future ovarian function and fertility. The diagnosis of adnexal torsion is particularly difficult in girls before the menarche during which time the clinical examination is very delicate. We review the recent literature and laparoscopic advances in this domain and propose a management algorithm.  相似文献   
3.
Widely consumed daal (lentils) in Bangladesh are an ideal vehicle for iron (Fe) fortification; however, an acceptable portion size in meals needs to be determined to carry out a community feeding study in at-risk adolescent girls. A non-randomized crossover trial was conducted with n = 100 Bangladeshi girls (12.9 ± 2.0 years of age). Two recipes (thin and thick) and three portion sizes (25 g, 37.5 g, 50 g of raw lentil) of daal were served with 250 g of cooked white rice in a counter-balanced manner over 12 weeks. Each meal was fed to participants 5 days/week for two weeks. Ratings of hunger, satiety, and palatability were measured before and after each meal using Visual Analog Scales (VAS). The thick preparation in the 37.5 g portion (~200 g cooked) elicited higher VAS ratings of hunger, satiety, and palatability compared to all other meals. The 50 g portion of the thin preparation had VAS ratings similar to those of the 37.5 g thick preparation. Consuming the 37.5 g portion of fortified daal would provide 6.9 mg Fe/day to girls in a community-based effectiveness study. This would meet ~86% and ~46% of the Recommended Dietary Allowance (RDA) for Fe for girls aged 9–13 and 14–18 years, respectively.  相似文献   
4.
PurposeIt is well known that pubertal timing affects adolescents' externalizing behaviors, but it is unknown if this effect lasts into adulthood. This study assessed if and when the early maturation effect wanes, specifically in two domains of externalizing behaviors: nonviolent and violent behaviors.MethodsUsing data from the National Longitudinal Study of Adolescent to Adult Health (Add Health) that include age-appropriate items of violent and nonviolent behaviors assessed from ages 11–30 over four waves (N = 4,255), we conducted a series of longitudinal growth curve analyses to evaluate the effect of pubertal timing on the trajectories of nonviolent and violent externalizing behaviors for males and females.ResultsCompared to later maturing male peers, early maturing males reported significantly elevated overall externalizing, nonviolent, and violent behaviors throughout adolescence, but became indistinguishable from on-time and late-maturing counterparts in young adulthood. Similarly, early maturing females showed higher levels of overall externalizing and nonviolent behaviors than later maturing counterparts, but no effect of pubertal timing was seen on the trajectories of violent behaviors. However, early maturing females' overall externalizing and nonviolent behaviors also became indistinguishable from on-time and late-maturing females after adolescence.ConclusionsThese findings clarify the differential effect of early maturation on nonviolent and violent behaviors, especially in females, and highlight the short-lived nature of the effects of early pubertal timing.  相似文献   
5.
PurposeThis study explored the association of maternal age at menarche (AAM) with pubertal timing among girls and boys in Chongqing, China.MethodsPubertal development of 1,237 children (542 girls and 695 boys) were examined half-yearly through inspection and palpation from April 2014 to June 2019. Characteristics of parents and maternal AAM were collected by a parental questionnaire at baseline. Maternal AAM was used both as a continuous and a categorical variable in Cox regression models.ResultsA total of 1,198 children (528 girls and 670 boys) were included in the study. In the simple Cox model, earlier maternal AAM was associated with girls' earlier menarche, breast and pubic hair development, and boys' first ejaculation, testicular development, and genital development. When adjusting for children's body mass index z-scores (BMIz) and socioeconomic covariates, we found that girls whose mothers had early AAM had a higher risk of earlier onset of menarche (hazard ratio [HR]: .922, 95% confidence interval [CI]: .852–.998 for continuous maternal AAM, HR: 1.297, 95% CI: 1.041–1.616 for maternal AAM ≤13 years), and boys whose mother achieved menarche earlier experienced a higher risk of earlier onset of first ejaculation (HR: .896, 95% CI: .830–.968). Children's BMIz were related to all nine pubertal milestones. Parental education and relationship, birth weight, parity, and family type were also associated with pubertal timing.ConclusionsEarlier maternal AAM was related to earlier pubertal timing in both girls and boys in Chongqing, especially girls' age at menarche and boys' first ejaculation. Children's BMIz was the most consistent factor for pubertal timing. Children's BMIz and socioeconomic conditions had greater influence on most pubertal milestones than maternal AAM.  相似文献   
6.
BACKGROUND: Body mass index (BMI) is the simplest way to measure obesity; therefore, it is chosen by many authorities as a screening method for adolescent obesity. Body mass index is positively correlated with the complications of childhood and adolescent obesity, such as hypercholesterolemia, insulin resistance, hyper-tension and long-term development of cardiovascular diseases. The aim of the present study was to produce percentile curves for bodyweight, height and BMI in a representative sample of adolescent girls living in urban and rural areas of Edirne, Turkey, and to compare these percentile curves with curves from other countries. METHODS: The present study was a cross-sectional study, including a representative sample of 1687 adolescent girls from rural and urban areas of Edirne, who were evaluated between May and July 2001. Bodyweight and height were measured using standard procedures. Body mass index (kg/m2) was calculated as the ratio of bodyweight to body height squared. Smoothed percentiles for these variables were calculated using polynominal regression models. Crude weight, height and BMI percentile values, as well as smoothed percentile curves are presented. RESULTS: Body mass index, weight and height reference curves for adolescent girls were produced. When we compared the BMI values of subjects in the present study with those of other countries, 85th and 95th percentiles of BMI in the present study were found to be generally lower than those for other ethnicities. CONCLUSION: Our findings show ethnic differences in BMI among adolescent girls. It will be usefull for each country to produce its own BMI percentiles.  相似文献   
7.
住院网络成瘾青少年的父母养育方式与人格特征   总被引:4,自引:0,他引:4  
目的探讨住院网络成瘾(Internet Addiction Disorder,IAD)青少年的父母养育方式及人格特征。方法采用网络成瘾临床诊断标准、艾森克人格问卷(EPQ),父母养育方式评定量表(EMBU),对596名被诊断为IAD的青少年施测,比较住院IAD者与对照组的差异。结果IAD青少年父亲情感温暖(FF1)分值低于对照组,过分干涉(FF3)、拒绝否认(FF5)分值高于对照组。IAD青少年的母亲情感温暖(MF1)分值亦低于对照组,而过分干涉保护(MF2)、拒绝否认(MF3)及惩罚严厉(MF4)因子均高于对照组(P<0.01)。IAD青少年的内外向(E)因子分明显低于对照组(P<0.01)、精神质(P)因子分高于对照组(P<0.05)。结论住院IAD青少年存在不良的家庭教养方式,同时存在人格问题。  相似文献   
8.
目的:探讨滋阴泻火中药对青春期启动大鼠骨骼生长及相关基因的作用和机理。方法:将150只4周龄青春发育早期SD大鼠,随机分为空白对照组、中药小剂量组、中药中剂量组、中药大剂量组、Gn-RHa组,共5组,每组30只。每周测量大鼠身长,并分别在给药第4周、8周及停药4周时,每组各取10只大鼠处死,测量胫骨长度并留骺软骨标本。采用荧光定量PCR法,检测各组大鼠骺软骨IGF-1、IGF-1R、cbfα1基因表达。结果:中药中、大剂量组和GnRHa组身长生长速度及胫骨生长速度较空白对照组减慢,但停药后对大鼠成年期身长无影响。中药中、大剂量组及GnRHa组大鼠治疗后骨骼相关生长基因IGF-1、IGF-1R基因表达下调,但是停药后,成年期各组大鼠IGF-1、IGF-1R基因表达无差异。表明中药及西药对大鼠骺软骨cbfα1基因表达无明显影响。结论:滋阴泻火中药对青春期启动大鼠长骨生长有一定的抑制作用,这种作用与药物通过下丘脑-垂体-生长(骨骼)轴的调控,从而下调大鼠骺软骨IGF-1、IGF-1R基因表达有关,停药后,这种抑制作用是可逆的。  相似文献   
9.
10.

Background

Recent conceptual models argue that early life adversity (ELA) accelerates development, which may contribute to poor mental and physical health outcomes. Evidence for accelerated development in youths comes from studies of telomere shortening or advanced pubertal development following circumscribed ELA experiences and neuroimaging studies of circuits involved in emotional processing. It is unclear whether all ELA is associated with accelerated development across global metrics of biological aging or whether this pattern emerges following specific adversity types.

Methods

In 247 children and adolescents 8 to 16 years of age with wide variability in ELA exposure, we evaluated the hypothesis that early environments characterized by threat, but not deprivation, would be associated with accelerated development across two global biological aging metrics: DNA methylation (DNAm) age and pubertal stage relative to chronological age. We also examined whether accelerated development explained associations of ELA with depressive symptoms and externalizing problems.

Results

Exposure to threat-related ELA (e.g., violence) was associated with accelerated DNAm age and advanced pubertal stage, but exposure to deprivation (e.g., neglect, food insecurity) was not. In models including both ELA types, threat-related ELA was uniquely associated with accelerated DNAm age (β = .18) and advanced pubertal stage (β = .28), whereas deprivation was uniquely associated with delayed pubertal stage (β = ?.21). Older DNAm age was related to greater depressive symptoms, and a significant indirect effect of threat exposure on depressive symptoms was observed through DNAm age.

Conclusions

Early threat-related experiences are particularly associated with accelerated biological aging in youths, which may be a mechanism linking ELA with depressive symptoms.  相似文献   
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