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1.
Objective: This study presents total body volume (TBV) and regional body volume, and their relationships with widely used body composition indices [BMI, waist circumference (WC), and percentage body fat (% fat)] in severely obese adults (BMI ≥35 kg/m2). Research Methods and Procedures: We measured TBV, trunk volume (TV), arm volume (AV), leg volume (LV), and WC and estimated % fat in 32 severely obese persons with BMI 36 to 62 kg/m2 (23 women; age, 19 to 65 years; weight, 91 to 182 kg) and in 58 persons with BMI <35 kg/m2 (28 women; age, 18 to 83 years; weight, 48 to 102 kg) using a newly validated 3‐day photonic image scanner (3DPS, Model C9036–02, Hamamatsu Co., Japan) and calculated TV/TBV, AV/TBV, and LV/TBV. Results: Men had significantly larger TBV and higher TV/TBV and AV/TBV, but significantly lower LV/TBV than women, independently of BMI. TV/TBV increased while AV/TBV and LV/TBV decreased with increasing BMI, WC, and % fat, and the rate of increase in TV/TBV per % fat was significantly greater in severely obese individuals than in individuals with BMI <35 kg/m2. The relationships for TBV with % fat were much lower than with BMI or WC. Conclusion: Body volume gains were mainly in the trunk region in adults, irrespective of sex or BMI. For a given BMI, WC, or % fat, men had a significantly larger TV than women. The implication is that men could have higher health risks due to having higher trunk body weight as a proportion of total body weight compared with severely obese or less severely obese women.  相似文献   

2.
植物油体研究进展   总被引:1,自引:0,他引:1  
胡佳  刘春林 《植物学报》2017,52(5):669-679
油体是生物体细胞中一种重要的细胞器结构,由单层磷脂酸膜包裹中性脂肪酸形成,膜上镶嵌有决定油体性质的多种膜蛋白。油体在能量储存、细胞生殖分化、抗病抗寒和发育调控等多种生命活动中起重要作用。该文对植物油体的结构、生物学功能、不同组织中油体的形成情况以及油体膜蛋白的研究进展进行了多方位概述和总结,以期为后续研究提供有益的参考。  相似文献   

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Objective : Regulation of growth and development, clinical assessment, and obesity are among the areas of nutritionrelated research, wherein accurate assessment of body composition is important. We want to test the hypothesis that dual-energy X-ray absorptiometry (DXA) measurements are reproducible in healthy girls. Research Methods and Procedures : We determined total body composition measurements in healthy prepubertal girls using DXA twice, 6 weeks apart. Results : We studied 61 healthy, normal-weight, prepubertal girls, aged 4.8 years to 10.3 years. The girls' DXA-derived mean weight between visits 1 and 2 significantly increased (27.14 kg vs. 27.80 kg, P<0.0001). The increased weight was due to significant increases in total body fat-free mass (FFM) (19.53 kg vs. 19.89 kg,P<O.001), total body bone mass (1.05 kg vs. 1.07 kg, P<0.0001), and total body fat mass (7.61 kg vs. 7.91 kg,P<0.03). The girls' DXA-derived mean total trunk mass between visits 1 and 2 significantly increased (11.23 kg vs. 11.63 kg, p<<0.0001), as did total leg mass (9.33 kg vs. 9.53 kg, p<<0.001), although no significant differences were observed in total arm mass (2.52 kg vs. 2.54 kg, p< = 0.37). The Pearson coefficient of correlation (r) and total coefficient of variation (CV) for intraindividual measurements by DXA were: weight—r = 0.99, CV= 1.97%; total body FFM—r = 0.96, CV = 2.30%; total body bone mass—r = 0.99, CV = 2.08%; total body fat mass—r = 0.96, CV = 6.55%; percentage total body fat— r = 0.91, CV = 5.69%; total trunk mass—r = 0.96, CV = 3.59%; total arm mass—r = 0.95, CV = 4.09%; and total leg mass—r = 0.99, CV = 2.75%. Discussion : Total body FFM, total body bone mass, total body fat mass, percentage of total body fat mass, as well as regional mass determinations by DXA, were highly reproducible in healthy, normal-weight, prepubertal girls. We highly recommend the use of DXA for total body composition studies in girls aged 5 years to 10 years.  相似文献   

5.

Background

Obesity and overweight are increasing in prevalence in developed countries as a result of changing dietary habits and a lack of physical activity. The purpose of the present study was to evaluate the changes in body composition during short-term overfeeding using the three-component model, which is composed of fat mass (FM), total body water (TBW), and fat-free dry solids (FFDS).

Methods

Ten healthy men completed 3 days of overfeeding during which they consumed 1,500 kcal/day more energy than consumed in their normal diets. Body composition was evaluated at three time points: the day before and after their normal diets and the day after the 3-day overfeeding diet.

Results

Before and after their normal diets, there were no significant differences in body weight and composition, but after 3 days of overfeeding, body weight, TBW, and FFDS increased 0.7, 0.7, and 0.2 kg, respectively (P <0.0001). There was no significant difference in FM between the normal and overfeeding diets.

Conclusion

This study suggests that TBW gain contributes to weight gain following a short-term overfeeding.  相似文献   

6.
Objective: To examine the relationship between physical activity, TV watching, and weight in U.S. youth ages 14 to 18 years. Research Methods and Procedures: Data from a nationally representative sample of 15,143 U.S. high‐school students participating in the 1999 Centers for Disease Control and Prevention (CDC) Youth Risk Behavior Survey were examined. Prevalence rates of participation in moderate physical activity (MPA), vigorous physical activity (VPA), and television watching (TV) were determined. The association between MPA, VPA, TV and the body mass index (BMI) and overweight status (BMI ≥85th percentile of age‐ and sex‐specific CDC/National Center for Health Statistics reference values) were examined by analysis of covariance and logistic regression. Results: Overall, 45% reported participating in MPA ≥3 d/wk, 65% reported participating in VPA ≥3 d/wk, and 25% reported watching TV ≥4 h/school day. Boys reporting six to seven bouts of MPA had a significantly lower BMI compared with boys reporting three to five or less than two. The mean BMI differed significantly between the lowest and highest levels of MPA groups in girls. The mean BMI was significantly lower in the highest VPA group compared with the other two groups in both sexes. There was a significant graded response for BMI across all levels of TV. Decreased levels of MPA and 3 to 4 days of VPA were significantly associated with an increased risk of overweight in boys when compared with those engaging in 6 to 7 d/wk (odds ratio = 1.26 to 1.37). A graded response existed between TV and overweight in both sexes. Boys and girls were ~20% to 25% less likely to be classified as overweight if they reported 2 to 3 hours of TV per day and ~40% less likely to be classified as overweight if they reported ≤1 hour of TV per day compared with those who watched ≥4 hours of TV. In general, youth who engaged in less physical activity watched more TV per week. Discussion: Increased levels of physical activity are associated with a lower BMI and less TV watching. However, the relationship between TV watching and weight status is more pronounced.  相似文献   

7.
STEWART, TIFFANY M., DONALD A. WILLIAMSON, MONIQUE A. M. SMEETS, AND FRANK L. GREENWAY. Body morph assessment: preliminary report on the development of a computerized measure of body image. Objective: To develop a prototype of the Body Morph Assessment (BMA), and to test the reliability and validity of this new measure of body image. The BMA is a realistic and relatively simple procedure that uses computer morphing for the assessment of body image. For the purposes of this preliminary study, a prototype of the BMA was developed for usage with white women ranging from very thin to obese. Research Methods and Procedures: A total of 72 subjects participated in tests of reliability, content, and convergent validity of the BMA. Results: The reliability and validity of the BMA was supported by the results of this study. In a test of convergent validity, the measures of current, ideal, and reasonable body size were positively correlated with their equivalents from a similar body image assessment procedure. In addition, reliability coefficients were found to be satisfactory for all variables. Participants found the human figural stimuli to be realistic. Discussion: These preliminary findings support the reliability and validity of the BMA with white women. Given these positive findings, we plan to extend the procedure to males and to other racial and ethnic groups.  相似文献   

8.
In larch (Larix decidua Mill.) microspores a new type of nuclear bodies has been found which are an element of the spatial organization of the splicing system in plant cell. These are bizonal bodies, ultrastructurally differentiated into a coiled part and a dense part. Using immunocytochemistry and in situ hybridization at the EM level, the coiled part of the bizonal body was found to contain snRNA including U2 snRNA, Sm proteins and nucleolar proteins of the agyrophilic type and fibrillarin. The dense part contains Sm proteins but lacks snRNA. Such a separation of macromolecules related to splicing occurring within the bizonal bodies microspore is striking by the similarity of these bodies to amphibian oocyte snurposomes. The occurrence in plant cells, beside widely known coiled bodies (CBs), also of other nuclear bodies related to splicing proves that in plants similarly as for animals the differentiation among domains containing elements of the splicing system occurs.  相似文献   

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Human obesity is a growing epidemic throughout the world. Body mass index (BMI) is commonly used as a good indicator of obesity. Body adiposity index (BAI = hip circumference (cm)/stature (m)1.5 ? 18), as a new surrogate measure, has been proposed recently as an alternative to BMI. This study, for the first time, compares BMI and BAI for predicting percent body fat (PBF; estimated from skinfolds) in a sample of 302 Buryat adults (148 men and 154 women) living in China. The BMI and BAI were strongly correlated with PBF in both men and women. The correlation coefficient between BMI and PBF was higher than that between BAI and PBF for both sexes. For the linear regression analysis, BMI better predicted PBF in both men and women; the variation around the regression lines for each sex was greater for BAI comparisons. For the receiver operating characteristic (ROC) analysis, the area under the ROC curve for BMI was higher than that for BAI for each sex, which suggests that the discriminatory capacity of the BMI is higher than the one of BAI. Taken together, we conclude that BMI is a more reliable indicator of PBF derived from skinfold thickness in adult Buryats. Am J Phys Anthropol 152:294–299, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   

11.
Objective: To compare the self‐perception of overweight in the study population according to sex, race/ethnicity, and socioeconomic status and to compare the self‐perception of overweight among individuals classified as normal weight, overweight, and obese. Research Methods and Procedures: Data from 5440 adults who participated in the 1994 to 1996 Continuing Survey of Food Intakes by Individuals and the Diet and Health Knowledge Survey conducted by the U.S. Department of Agriculture were analyzed. Data for analysis included self‐perceived weight status, self‐reported weight and height, and demographic and socioeconomic data. Underweight individuals, defined as those with a body mass index <18.5 kg/m2, were excluded from the analysis. Results: Self‐perception of overweight was more common in women compared with men and in whites compared with blacks or Hispanics. Both the correct and incorrect perception of overweight was more common in normal weight and overweight white women compared with black women. More overweight and obese white men correctly perceived their overweight status compared with black men. Multiple logistic regression showed that the odds ratio of perceived overweight was significantly higher in women, whites, and individuals with higher body mass index, higher income, and higher education. Discussion: Self‐perceived overweight varied by sex, race/ethnicity, and socioeconomic status. Erroneous perception of body weight may have important health and behavioral implications. In particular, a considerable proportion of overweight men may be at risk of obesity if they continue to perceive themselves as having normal weight.  相似文献   

12.
研究龟鳖的两性异形对理解形态适应具有重要意义。通过测量41只(21♀,20♂)成体四眼斑水龟(Sacalia quadriocellata)的20个形态特征指标,研究四眼斑水龟个体大小和体形的两性异形。结果表明:除头长、头宽、尾长和尾长肛前段长外,四眼斑水龟其他的形态特征均与背甲长呈正相关。雌性的背甲长、腹甲长、腹甲中线长、腹甲曲线长显著大于雄性;雄性的头长、头宽、后肢长、尾长和尾长肛前段长显著大于雌性;雌雄两性的体重、体周长、前肢长、腹甲宽、肛盾切口长、肛盾切口宽以及除背甲长外的所有背甲形态特征指标均无显著差异。研究结果表明,四眼斑水龟存在个体大小和体形两性异形。  相似文献   

13.
生物体的外在形态(个体大小及异速生长)不仅是分类学的重要依据, 也是影响生物与环境相互作用的重要功能性状。昆虫体型的地理分异及其机制是昆虫生物地理学的重要基础。本文基于中国省级行政区的瓢虫体型、分布和环境因子数据, 运用相关和回归分析, 探索了中国瓢虫体型(体长、体宽与长宽比)的纬度地带性及其与环境因子的关系。为了确定营养级对瓢虫体型特征的影响, 我们对全部瓢虫、植食性瓢虫和捕食性瓢虫分别进行分析。研究结果表明: (1)瓢虫的体型大小具有显著的纬度地带性, 即纬度越高, 瓢虫的体长或体宽越大, 符合贝格曼法则。与温度相关的环境因子是导致瓢虫体型大小地理分异的主要环境因素, 因为瓢虫以成虫越冬, 体型越大则能量储存越多, 冬眠期间的耐饥力越强; (2)由于食性和食物空间分布的差异, 在各个纬度上, 植食性瓢虫体型总是大于捕食性瓢虫; 捕食性瓢虫的长宽比与纬度呈显著正相关, 即纬度越高, 瓢虫体型越狭长; 而植食性瓢虫的长宽比与纬度没有显著的相关性; 捕食性瓢虫的长宽比与年降水量呈显著负相关, 因为年降水量降低导致植被的斑块化增加, 引起捕食对象分布更为分散, 从而要求瓢虫具有更强的飞行能力, 即更大的长宽比。综上所述, 在省级尺度上, 温度和降水分别主要影响瓢虫的大小和长宽比, 其效应随营养级(食性)的变化而变化。  相似文献   

14.
1991~ 1998年对内蒙古阿巴嘎旗那仁宝力格苏木布氏田鼠 (Microtusbrandti)体长、体重和胴体重资料进行了调查和分析 ,得到如下结论 :田鼠体长、体重、胴体重的均值在低密度回升期均逐年增高 ;雌性越冬鼠的胴体重均值低于雄性越冬鼠且有显著性差异 (P <0 0 5 ) ;秋季雄鼠与雌鼠的 3项指标的均值无显著差异(P >0 10 ) ,体长、体重和胴体重间相关极显著 (P =0 0 0 0 1)。分别给出了体重与体长 :胴体重与体长的模型W =aLb,其中W为体重或胴体重 ,L为体长 ;胴体重与体重的关系适合于模型NW =W / (a bW ) ,其中NW为胴体重 ,W为体重。  相似文献   

15.
Objective: To examine the relationship between self‐estimated whole body size and fatness and whole body and regional composition, and the relationship between self‐estimated whole body fatness and self‐estimated regional fatness in Japanese university students. Research Methods and Procedures: This was a cross‐sectional study using Japanese university students (110 men and 79 women). The percentage of body fat, fat mass (FM), and fat‐free mass (FFM) were measured by underwater weighing and used as body composition variables. Subcutaneous fat thicknesses were determined at seven sites by ultrasonography to estimate regional body composition, and six circumferences and four breadths to estimate regional size. Relative body size and fatness were self‐estimated using a questionnaire. Results: Only women tended to estimate themselves as being fatter than they actually were. Self‐estimated body fatness moderately correlated with the percentage of body fat (men, r = 0.41; women, r = 0.40) FM (men, r = 0.50; women, r = 0.51), and body mass index (r = 0.56 for men and 0.56 for women). After adjusting for the percentages of body fat and FM, self‐estimated fatness correlated with body mass index (r = 0.31 for men and r = 0.37 for women). Among self‐estimated regional fatness, self‐estimated abdominal fatness had the strongest correlation with self‐estimated whole body fatness in both genders. Discussion: The low correlation between estimated and actual body fatness in both genders indicates that Japanese university students, especially women, inaccurately estimate their percentage of body fat. In fact, both men and women primarily estimate their whole body fatness by body weight relative to height.  相似文献   

16.
Objective: The objective of this study was to determine the effect of body hair (scalp and facial) on air displacement plethysmography (BOD POD) estimates of percentage of body fat. Research Methods and Procedures: A total of 25 men (31.4 ± 8.0 years, 83.4 ± 12.2 kg, 181.8 ± 6.9 cm) agreed to grow a beard for 3 weeks to participate in the study. Total body density (g/cm3) and percentage of body fat were evaluated by BOD POD. To observe the effect of trapped isothermal air in body hair, BOD POD measures were performed in four conditions: criterion method (the beard was shaven and a swimcap was worn), facial hair and swimcap, facial hair and no swimcap, and no facial hair and no swimcap. Results: The presence of only a beard (facial hair and swimcap) resulted in a significant underestimation of percentage of body fat (16.2%, 1.0618 g/cm3) vs. the criterion method (17.1%, 1.0597 g/cm3, p < 0.001). The effect of scalp hair (no swim cap worn) resulted in a significant underestimation in percentage of body fat relative to the criterion method, either with facial hair (facial hair and no swimcap; 14.8%, 1.0649 g/cm3) or without facial hair (no facial hair and no swimcap; 14.8%, 1.0650 g/cm3, p < 0.001 for both). Discussion: A significant underestimation of percentage of body fat was observed with the presence of facial hair (~1%) and scalp hair (~2.3%). This underestimation in percentage of body fat may be caused by the effect of trapped isothermal air in body hair on body‐volume estimates. Thus, excess facial hair should be kept to a minimum and a swimcap should be worn at all times to ensure accurate estimates of body fat when using the BOD POD.  相似文献   

17.
目的:通过测量军校毕业学员的人体成分,探讨军校毕业学员与普通居民的区别,并为建立相关标准提供依据。方法:按飞行院校、分流院校、合训院校、技术院校和士官学校分层抽取5968名毕业学员,分别进行人体成分检测,根据结果划定5%-95%分布上下限。并就军校毕业学员的体脂百分比、体质指数(BMI)、肌肉百分比、骨质百分比指标与同年龄、同性别城乡居民进行比较。结果:1军队院校毕业学员体脂百分比的参考值范围为10.3%-20.7%(男)和19.2%-30.1%(女);BMI参考值范围为19.30-25.70(男)和18.00-23.99(女);瘦体重百分比参考值范围为79.3%-86.7%(男)和69.9%-80.7%(女);肌肉百分比参考值范围为74.2%-84.0%(男)和65.2%-75.3%(女);骨质百分比参考值范围为5.0%-5.8%(男)和4.7%-5.5%(女)。2与同年龄、同性别城乡居民比较,军队院校毕业学员的体脂百分比明显较少,肌肉百分比、骨质百分比明显较高。结论:1军队院校毕业学员的身体成分数据明显优于同年龄、同性别城乡居民,总体表现为体脂较少,肌肉和骨质较多。2军队院校毕业学员的体质状况不能简单采用民用标准,需建立一套符合军校毕业学员的标准。  相似文献   

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To clarify the role of leptin as a signal of energy status in humans, this study investigated the relationship of leptin to measures of body composition, maturity, and lifestyle factors in a lean sample of 293 male and 303 female Filipino adolescents (age 14-16 years). Participants were selected from the Cebu Longitudinal Health and Nutrition Survey, a representative birth cohort study begun in 1983. Using IOTF criteria, the prevalence of overweight (2.2%) and obesity (0.3%) were extremely low, and leptin levels were among the lowest reported in any healthy population (mean: 0.78 and 3.57 ng/dl in males and females). As expected, adiposity was the strongest predictor of leptin, with triceps skinfold explaining 40.2 and 30.6% of leptin variance in males and females. In females, subscapular skinfold was a significant predictor of leptin independent of triceps, while no anthropometric measure predicted leptin independent of triceps in males. There were few relationships between lifestyle factors and leptin independent of adiposity. In males, leptin levels varied little across most of the triceps distribution, suggesting that the leptin-adipose regulatory system is sensitive to very small changes in leptin in lean populations, at least among males. These findings add to the small but growing list of studies documenting differences in leptin biology among chronically lean populations.  相似文献   

20.
Summary Chief cells of the carotid and aortic body chemoreceptors possess numerous cytoplasmic dense-core vesicles which are known to contain primarily dopamine. Following fixation in solutions containing 50 mM CaCl2, a 20–30 nm electron-dense particle (EDP) is often observed eccentrically located in many of the vesicles. Approximately 44 % of the carotid body and 16 % of the aortic body vesicles contain an EDP. The EDP probably represents the Ca+ + binding site critical to the stimulus-secretion coupling events culminating in exocytosis of these vesicles. The presence of Ca+ + in the cytoplasmic vesicles was verified by electron probe X-ray microanalysis.Supported by a Grant-in-Aid from the American Heart Association (77630) and by funds contributed in part by the Texas Affiliate. The authors wish to thank Ms. Teri Heitman for her excellent technical assistance  相似文献   

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