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1.
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   

2.
TATARANNI P ANTONIO JAMES B YOUNG, CLIFTON BOGARDUS, ERIC RAVUSSIN. A low sympathoadrenal activity is associated with body weight gain and development of central adiposity in Pima Indian men. To investigate the possible role of impaired sympathetic nervous system and/or adrenal medullary function in the etiology of human obesity, we studied 64 Pima Indian men (28 ± 6 years, 101 ± 25 kg, 34 ± 9% body fat, mean ± SD) in whom sympathoadrenal function was estimated at baseline by measurements of 24-hour urinary norepinephrine (NE) and epinephrine (Epi) excretion rates under weight-maintenance conditions. Body weight, body composition (hydrodensitometry), and body fat distribution (waist-to-thigh circumference ratio, W/T) were measured at baseline and follow-up. Follow-up data were available on 44 subjects who gained on average 8.4 ± 9.5 kg over 3.3 ± 2.1 years. In these subjects, baseline NE excretion rate, adjusted for its determinants (i.e., fat free mass, fat mass, and W/T), correlated negatively with bodyweight gain (r=?0.38; p=0.009). Baseline Epi excretion rate correlated negatively with changes in W/T (r=?0.44; p=0.003). In conclusion, our data show for the first time that a low sympathetic nervous system activity is associated with body weight gain in humans. Also, a low activity of the adrenal medulla is associated with the development of central adiposity.  相似文献   

3.
Objective: To investigate the relationships among longitudinal weight status, body dissatisfaction, and attitude to weight loss among Korean children from the age of 7‐8 to 13‐14 years old. Research Methods and Procedures: 351 Korean school children's heights and weights were measured at the ages of 7‐8 and 13‐14 years old; at the age of 13‐14, they completed a questionnaire about body dissatisfaction and weight loss efforts. Results: At the age of 7‐8, 15.7% of children were overweight by International Obesity Task Force standards, as compared with 26.2% at the age of 13‐14. Of the 55 7‐ to 8‐year‐old overweight children, 85.5% were still overweight at the age of 13‐14 years old. Greater concerns about body image and stronger desires to be thinner were observed among stable overweight children and among those in whom there had been a rapid increase in BMI over the 6‐year study period. Girls favored thinner shapes than did boys, regardless of their weight status or BMI changes. In girls, the level of body dissatisfaction was related only to weight loss desire, regardless of weight status or changes in BMI. In boys, however, weight loss desire was related only to weight loss attempts and was independent of weight status, BMI changes, and level of body dissatisfaction. Discussion: Regardless of weight status, changes in BMI should be considered when dealing with body dissatisfaction and attitudes to weight loss in children.  相似文献   

4.
Objectives: To investigate if birth weight is related to both body mass index (BMI) and distribution of subcutaneous fat at adult age. Research Methods and Procedures: A 9‐year longitudinal study was performed in 229 subjects (192 women) with ages ranging from 27 to 36 years. Birth weight was retrieved by a questionnaire, and adult weight, height, skinfold thicknesses, and waist‐to‐hip ratio (WHR) were repeatedly measured at mean ages 27, 29, 31, and 36 years. BMI, sum of four skinfolds (S4S), the ratio between two truncal skinfolds and S4S (SS/S4S), and the ratio between WHR and the cross‐sectional area of the left thigh were calculated with the available data. Results: The adjusted model showed that in women, birth weight was significantly negatively related to adult S4S [β = ?5.211; (?9.768 to ?0.654)], waist circumference [β = ?1.449; (?2.829 to ?0.069)], and SS/S4S ratio [β = ?3.579; (?5.296 to ?1.862)]. In men, a significant negative association was observed between birth weight and adult WHR [β = ?1.096; (?2.092 to ?0.100)] only. Other relationships showed, although not significantly, the same negative trend, namely that lower birth weight is related to higher adult body fat mass (S4S) and a more truncal subcutaneous fat distribution (SS/S4S). No associations were found between birth weight and either adult BMI or the cross‐sectional area of the thigh. Discussion: Lower birth weight is, in both adult men and women, related to a higher adult subcutaneous fat mass and a more truncal distribution of subcutaneous fat, indicating a higher risk for obesity.  相似文献   

5.
The aim of our study was to determine if regain of body weight increases visceral fat in obese women and if regain of weight has a different effect upon pre- and postmenopausal women. Twenty obese women (11 pre- and 9 postmenopausal) underwent a very low energy diet (VLED) for 2 weeks to lose weight. They then regained body weight in spite of the recommended hypocaloric diet. No significant modifications in body fat distribution indexes were found by computed tomography between VLED and after regain of weight. No significant changes were found in metabolic variables. No interactions between menopausal status and regain of body weight were observed. In conclusion, regain of weight does not seem to cause an increase in visceral fat; both pre- and postmenopausal women showed the same body fat distribution before weight loss and after regain of weight.  相似文献   

6.
Captive studies and occasional trappings of wild individuals indicate that callitrichids have small size and body weight and lack sexual dimorphism. We compared body weights of captive and wild Callithrix jacchus obtained by repeatedly weighing subjects from two populations in Brazil. We obtained captive data by routinely weighing 138 individuals from the Universidade Federal do Rio Grande do Norte colony and wild data via regular trapping of 243 individuals in 15 free-ranging groups from IBAMA's field site in Nísia Floresta. We assigned all subjects to one of four age classes—infant, juvenile, subadult, and adult—according to their birth dates or size, reproductive status, and dental development. There is no significant difference between males and females in any of the four age classes, but captive subjects were heavier than wild ones in all age classes but infant. Reproductive and nonreproductive adult females showed no statistical difference in weight. These results accord with previous reports of lack of body size sexual dimorphism in common marmosets and suggest that differences between wild and captive common marmosets are not constitutional, but are instead a consequence of diet and physical activity. The absence of weight difference between reproductive and nonreproductive females suggests that any possible advantage from high rank is outweighed by the costs of reproduction in common marmosets.  相似文献   

7.
Neonatal Programming of Body Weight Regulation and Energetic Metabolism   总被引:3,自引:0,他引:3  
Programming is an epigenetic phenomena by which nutritional, hormonal, physical psychological and other stressful events acting in a critical period of life, such as gestation and lactation, modifies in a prolonged way certain physiological functions. This process was preserved by natural selection as an important adaptive tool for survival of organisms living in nutritional impaired areas. So, malnutrition during gestation and lactation turns on different genes that provide the organism with a thrifty phenotype. In the case of an abundant supply of nutrients after this period, those organisms that were adapted to a low metabolic waste and higher energy utilization will be in a higher risk of developing metabolic diseases, such as obesity, hyperlipidemia, diabetes mellitus and hypertension. The kind of malnutrition, duration and intensity are important for the type of programming obtained. We discuss some of the hormonal and metabolic changes that occur in gestation or lactation, when malnutrition is applied to the mothers and their offspring. Some of these changes, such as an increase of maternal triiodothyronine (T3), leptin and glucocorticoids (GC) and decrease in prolactin are by itself potential programming factors. Most of these hormones can be transfer through the milk that has other important macronutrients composition changes in malnourished dams. We discuss the programming effects of some of these hormones upon body weight and composition, leptin, thyroid and adrenal functions, and their effects on liver, muscle and adipose tissue metabolism and the consequences on thermogenesis.  相似文献   

8.
Objective: To investigate the relationship between body weight and the use of health care services among women from southern Germany. Research Methods and Procedures: Data were drawn from the 1994 to 1995 Monitoring of Trends and Determinants in Cardiovascular Disease Augsburg survey, covering a population‐representative sample of women 25 to 74 years old (n = 2301). Logistic regression models were used to calculate odds ratios (ORs) for the use of medical services by women with overweight (BMI 25.0 to 29.9 kg/m2) or obesity (BMI ≥ 30 kg/m2) in comparison with normal‐weight women (BMI < 25.0 kg/m2). Results: In multivariable analysis, obese women 50 to 74 years old were more likely than normal‐weight women to delay cancer screening procedures, such as manual breast examination and Papanicolaou smear (OR 0.52, 95% confidence interval 0.37 to 0.74) in the previous 12 months. However, the relationship between obesity and cancer screening was not found to be significant in 25‐ to 49‐year‐old women (OR 0.92, 95% confidence interval 0.62 to 1.36). Neither in the 25‐ to 49‐year‐old age group nor in the 50‐ to 74‐year‐old age group were independent relationships between higher body weight and total physician visits, hospitalizations, or medication use observed. Discussion: Obese women tended to use medical services with greater frequency due to obesity‐related diseases. However, postmenopausal women with a BMI ≥ 30 kg/m2 were more likely to delay routine cancer screening, putting them at a greater risk for death from breast, cervical, and endometrial cancer. Thus, obese postmenopausal women should be targeted for increased screening.  相似文献   

9.
Total free-living energy expenditure (TEE) was measured in 9 normal weight controls and 5 obese women using the doubly labeled water (DLW) method. Resting energy expenditure (REE) and the thermic effect of food (TEF) were measured by indirect calorimetry and the energy cost of physical activity (PA) calculated by deduction, in order to quantify the components and identify determinants of free-living TEE. Although REE was quantitatively the major component of TEE in both groups, PA best explained the variability, contributing 76% to the variance in free-living TEE. The obese women had elevated values for TEE (12397+/-2565 vs. 8339+/-1787 kJ/d, mean+/-SD; p<0.00S), compared with the control women. PA (5071+/-2385 vs. 2552+/-1452; p<0.0S) and REE (6393+/-678 vs. 5084+/-259; p<0.000S) were also raised in the obese, whereas TEF was not significantly different between the groups, accounting for 7.6% of energy expenditure for the obese and 8% for the control subjects. Body weight was the single best determinant of mean daily free-living TEE across both groups. We conclude that PA and body weight are the main determinants of free-living TEE .  相似文献   

10.
参考家系鸡黑素皮质素受体3基因多态性与体重关系研究   总被引:15,自引:0,他引:15  
鼠遗传学研究显示黑素皮质素受体3(melanocortin-3 receptor,MC3R)和MC4R在能量平衡控制中具有互补作用。敲除MC3R基因鼠表现为独有的代谢综合征和增加脂肪重量。以8周龄高体重或低体重独立选择的高体重系(high weight,HW)和低体重系(low weight,LW)白洛克鸡3代参考家系群体作为实验材料,发现了5个新的MC3R基因单核苷酸多态性(single nucleotide polymorphisms,SNPs);建立了基于限制性内切酶Dde I的MC3R基因型的PCR-RFLP分子检测方法。方差分析结果显示MC3R基因型显著影响公鸡和母鸡的体重,以及公鸡腹脂含量。该结果建议MC3R基因可以作为侯选基因解释杂交鸡体重显著差异的原因。  相似文献   

11.
Prevention of obesity and increase in longevity in obesity-prone rodents can be achieved by long-term moderate dietary restriction. In order to examine the likelihood that caloric restriction could have similar salutary effects in humans, rhesus monkeys, after reaching mature adult stature, were placed on a protocol to clamp or stabilize body weight by weekly caloric adjustment Further weight gain was prevented by this caloric titration procedure, and thus middle-age onset obesity, which is very common in this species, was prevented. The present study analyzed daily food intake for six weight-clamped monkeys and six ad libitum fed age-matched animals over a 3- year period, ages 18.5 to 21.5 years. After approximately 9 years of caloric restriction the daily calorie load to maintain stable adult body weight proved to be 40% less than the amount ingested by ad libitum fed animals. Calories per kg body weight did not differ significantly between the groups although the ad libitum fed animals were significantly fatter than the weight-clamped group. Prevention of obesity using this weight clamp protocol has also maintained lower insulin levels and higher glucose tolerance in the restricted animals.  相似文献   

12.
比格犬MC4R基因多态性与体重相关性的研究   总被引:11,自引:3,他引:8  
张轶博  巴彩凤  苏玉虹  曾瑞霞 《遗传》2006,28(10):1224-1229
为了分析比格犬黑素皮质素受体-4基因多态性与犬体重的关系, 根据犬MC4R基因DNA外显子序列, 设计MC4R基因特异PCR引物1对, 犬DNA经PCR扩增, 克隆和测序, 寻找和确定犬MC4R基因的多态性位点, 分析多态性与犬体重的关系。结果在比格犬MC4R基因中发现2处单碱基缺失突变, 1个单碱基颠换变异, 存在Psh AⅠ酶切位点, 并基于PshAⅠ酶切位点建立了PCR-RFLP技术。统计分析显示犬MC4R基因型与体重显著相关, 可以考虑将MC4R基因作为犬体重的候选基因。  相似文献   

13.
Objective: To test the hypothesis that major depression predicts an increase in long‐term body weight variability (BWV). Research Methods and Procedures: This was a prospective community‐based single‐age cohort study of young adults (N = 591) followed between the ages of 19 and 40. Following initial screening, information was derived from six subsequent semistructured diagnostic interviews conducted by mental health professionals. Major depression was diagnosed on the basis of DSM criteria. BWV was defined as the root mean square error of a regression line fitted to each individual's BMI values over time. Multiple regression analysis was used to test the association between major depression and BWV while controlling for potentially confounding variables including antidepressant treatment, eating disorder symptoms, and physical activity. We used random effects models to determine the temporal relationship between repeated measures of major depression and body weight change. Results: A highly significant positive association between major depression and BWV was found, whereas major depression was not associated with BMI level or BMI trend. Depression severity showed a dose‐response‐type relationship with the magnitude of BWV. After controlling for potentially confounding variables including antidepressant use, eating disorder symptoms, smoking, and physical activity, major depression remained a significant predictor of BWV (β= 0.13, p < 0.001). Longitudinal analysis revealed a unidirectional association between major depression and a later increase in body weight change rate irrespective of antidepressant medication. Discussion: Results from this study implicate depression as an important risk factor for increased BWV. Given increasing evidence for a link between major depression and both diabetes and cardiovascular disease, current results encourage further research on depression, BWV, and negative health outcomes.  相似文献   

14.
Objective: This study examined dieting, weight perceptions, and self‐efficacy to eat healthy foods and engage in physical activity and their relationships to weight status and gender among American Indian elementary schoolchildren. Research Methods and Procedures: Data for this study were collected as part of the baseline examination for the Pathways study. Participants were 1441 second‐ through third‐grade American Indian children in 41 schools representing seven tribes in Arizona, New Mexico, and South Dakota who filled out a questionnaire and had heights and weights taken. Results: Forty‐two percent of the children were overweight or obese. No differences were found between overweight/obese and normal weight children for healthy food intentions or self‐efficacy. Heavier children (especially those with body mass index > 95th percentile) were more likely to have tried to lose weight or were currently trying to lose weight. No gender differences were found. Normal weight children chose a slightly heavier body size as most healthy compared with overweight/obese children. Discussion: The results indicate that children are concerned about their weight and that weight modification efforts are common among overweight American Indian children. School, community, and family‐based programs are needed to help young people adopt lifelong healthful eating and physical activity practices.  相似文献   

15.
In search for SDHIs fungicides, twenty-five novel carboxamides containing a chalcone scaffold were designed, synthesized, and evaluated for antifungal activities against five pathogenic fungi. The results showed that compound 5 k exhibited outstanding antifungal activity against R. solani with an EC50 value of 0.20 μg/mL, which was much better than that of commercial SDHIs Boscalid (EC50=0.74 μg/mL). Moreover, compound 5 k also displayed promising antifungal activities against S. sclerotiorum, B. cinerea, and A. alternate (IC50=2.53–4.06 μg/mL), indicating that 5 k had broad-spectrum antifungal activity. Additionally, in vivo antifungal activities results showed that 5 k could significantly inhibit the growth of R. solani in rice leaves with good protective efficacy (57.78 %) and curative efficacy (58.45 %) at 100 μg/mL, both of which were much better than those of Boscalid, indicating a promising application prospect. Moreover, SEM analysis showed that compound 5 k could remarkably disrupt the typical structure and morphology of R. solani hyphae. Further SDH enzyme inhibition assay and molecular docking study revealed that lead compound 5 k had a similar mechanism of action as commercial SDHI Boscalid. These results indicated that compound 5 k showed potential as a SDHIs fungicide and deserved further investigation.  相似文献   

16.
张彬  龚元  于翔  吕军仪 《四川动物》2012,31(3):397-401
采用单因素方差分析等方法探讨人工养殖条件下体重、年龄和环境应激对菲牛蛭繁殖性能的影响。结果表明,体重对卵茧大小和湿质量及幼蛭体长、体宽和湿体质量无显著影响(P>0.05),而亲蛭性腺系数、平均产茧数、孵化率和平均孵化数在各组间差异显著(P<0.05),其中体重10~15g组明显高于其他组(P<0.05);年龄对亲蛭平均产茧数、孵化率、平均孵化数和卵茧大小影响显著(P<0.05),其中2~3年龄亲本具有最高的平均产茧数、孵化率和平均孵化数,8月龄亲本所产卵茧个体明显大于其他年龄组(P<0.05),而卵茧湿质量及幼蛭体长、体宽和湿体质量在各年龄组间均无显著差异(P>0.05)。环境应激对亲蛭的平均产茧数、孵化率和平均孵化数影响显著(P<0.01),其中1~2次操作应激下的平均产茧数和孵化数最高,无操作刺激下的孵化率略高于1~2次操作刺激(P>0.05),而卵茧大小和湿质量及幼蛭体长、体宽和湿体质量在各应激处理组间无显著差异(P>0.05)。本研究获得了菲牛蛭繁殖的最佳体重和年龄,建议繁育生产中挑选10~15g和2~3年龄的个体作为亲本,期间进行1~2次操作刺激可提高其繁殖性能。  相似文献   

17.
A series of novel chalcone malonate derivatives were synthesized and their antibacterial and antiviral activities were evaluated. All target compounds were characterized by spectral data. The results of antimicrobial bioassay showed that one compound (diethyl [3‐(naphthalen‐2‐yl)‐1‐(3‐nitrophenyl)‐3‐oxopropyl]propanedioate) showed excellent antibacterial activity against Xanthomonas oryzae pv. oryzae (Xoo), with an EC50 value of 10.2 μg/mL, which is significantly superior to bismerthiazol (71.7 μg/mL) and thiodiazole copper (97.8 μg/mL). At the same time, the mechanism of two compounds was confirmed by scanning electron microscopy. In addition, another compound (diethyl [3‐(naphthalen‐2‐yl)‐1‐(4‐nitrophenyl)‐3‐oxopropyl]propanedioate) showed significant curative activity to tobacco mosaic virus, with a value of 74.3 %, which was superior to 53.3 % of ningnanmycin. The results of microscale thermophoresis also showed that the Kd value of the combination of two compounds with the coat protein of tobacco mosaic virus was 0.211 and 0.166 μmol/L, which was better than 0.596 μmol/L of ningnanmycin. At the same time, the molecular docking of two compounds with tobacco mosaic virus‐coat protein shows that the compound is well embedded in the pocket between the two subunits of tobacco mosaic virus‐coat protein. These results show that chalcone derivatives containing malonate group can be considered as activators in the design of antibacterial and antiviral agents.  相似文献   

18.
Objective: It has been reported that electrical stimulation at the distal stomach can disrupt intrinsic gastric electrical activity and delay gastric emptying. Gastric dysrhythmia and impaired gastric emptying are associated with upper gastrointestinal symptoms and weight loss. The purpose of this study was to evaluate the effect of low‐frequency/long‐pulse gastric electrical stimulation (GES), at proximal and distal stomach, on canine gastric emptying, food intake, and body weight. Research Methods and Procedures: Eight dogs were surgically implanted with four pairs of electrodes along the greater curvature and a gastric tube at the dependent part of the stomach. Liquid gastric emptying at baseline, during proximal and distal GES at 6 cycles per minute, was assessed first by a dye dilution technique. Proximal and distal GES were then randomly delivered during feeding for 10 consecutive days, and food intake and body weight were recorded daily. Results: There was no significant difference in gastric emptying parameters among the various sessions. The mean daily food consumption was significantly reduced during both sessions of GES, resulting in significant immediate weight loss. Percentage weight loss was comparable between both sessions of GES. Discussion: Short‐term GES significantly reduced canine food intake and weight. This effect may not be related to changes in gastric emptying. GES may have a potential role in the treatment of obesity.  相似文献   

19.
Mycoplasmas are opportunistic parasites and some species are suggested to preferentially colonize tumor tissue in cancer patients. We could demonstrate that the annotated thymidine phosphorylase (TP) gene in the genome of Mycoplasma hyorhinis encodes a pyrimidine nucleoside phosphorylase (PyNPHyor) that not only efficiently catalyzes thymidine but also uridine phosphorolysis. The kinetic characteristics of PyNPHyor-catalyzed nucleoside and nucleoside analogue (NA) phosphorolysis were determined. We demonstrated that the expression of such an enzyme in mycoplasma-infected cell cultures dramatically alters the activity of various anticancer/antiviral NAs such as 5-halogenated pyrimidine nucleosides, including 5-trifluorothymidine (TFT). Due to their close association with human cancers, the presence of mycoplasmas may markedly influence the therapeutic efficiency of nucleoside-based drugs.  相似文献   

20.
The nocturnal Malagasy mouse lemurs are among the smallest primates worldwide. Several sibling species are known. Of these, the rufous and the gray mouse lemur differ with respect to morphology, genetics, and communication. They might also differ in seasonal reproduction and body weight changes. We investigated and compared reproductive activities and changes in monthly body weight in males and females of successfully breeding colonies of both species under the same photoperiodic conditions. Females of both species showed estrous cycles only during the long-day period. Rufous mouse lemur females seemed to have a shorter gestation than their sibling species (57 vs. 62 days). The number of estrous cycles (2.25 vs. 2.5/season) and their lengths (59 vs. 52 days) were similar. Litter size (2) seemed to be similar. Latency of estrous occurrence after photoperiodic stimulation was longer in Microcebus rufus than in its sibling species (71.6 and 42.3 days). The same was true for the onset of the growth of the testes. The rate of growth and size of the testes were similar, and precede the estrous onset in both species. The reproductive activity was shorter in both sexes of the rufous than of the gray mouse lemurs. In both species, body weight showed similar seasonal changes. Males lost more weight during the breeding season than females did. In rufous mouse lemurs, body weight was similar in both sexes during the nonbreeding season. In gray mouse lemurs, sexes differed throughout the year.  相似文献   

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