742 resultados para weight-age relationship
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The relation between otolith weight (OW) and the age of marine fish is studied. A total of 222 individuals of bighead white croaker, Pennahia macrocephalus were sampled seasonally in the mouth of the Beibu Gulf, the South China Sea, in 2007. Since there are no significant differences in sagittal OW between otolith in pairs (Pa parts per thousand yen0.05), the undamaged left sagittal otolith is used for age determination. The highest correlations among standard length, OW and fish ages are confirmed by linear, exponential and multinomial regression. Results show that sagittal OW overlaps only occasionally among age groups, and to individuals with similar standard length, the older and slower-growing fish has a heavier otolith because of the continued otolith material deposition. There are differences in sagittal OW among different age groups and significant positive linear relationship with age (P < 0.05). The age readings can be verified by plotting the sagittal OW versus the standard length for age groups, and the individuals with similar standard length but in different ages can be separated by sagittal OW frequency analysis. Mostly, the predicted ages using the regression between sagittal OW and ages are closed to the observed ages by counting annulus on scale. It indicates that the sagittal OW analysis is a useful technique for validating the accuracy of age determination by annuli counts, especially for individuals of similar size. Furthermore, the technique is applied for Pennahia macrocephalus with discussion in this paper.
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Fifteen percent of patients with Wilms`` tumor (WT) experience relapse. It has been suggested that weight and age may affect the chances of relapse. Few studies have investigated the role, if any, between P-glycoprotein (P-gp) and relapse. The authors assessed the prognostic value of tumor weight and age at diagnosis and asked whether some other potential biological markers, specifically P-gp protein expression, had a prognostic value in favorable-histology WT. No association between age and relapse could be found. Patients with tumor weight >= a parts per thousand yen550 g were 6 times more likely to relapse, whereas P-gp expression was positive in 18/40 (45%%) of the patients, of which 10/12 (83.3%%) relapsed and 8/28 (28.6%%) did not. Further studies are necessary to elucidate whether or not P-gp is related to relapse in patients with histologically favorable Wilms`` tumor. If confirmed, the protein may be used in the future as a target for new drugs and treatments for this group of patients.
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O presente estudo analisou a relação peso-comprimento e uma série de aspectos da biologia reprodutiva de Anableps anableps da foz do rio Maracanã, no estado brasileiro do Pará. Os espécimes foram coletados por meio de duas redes de emalhar de 30 m de comprimento, com malhas de 15 e 20 mm, e com um puçá com um metro de diâmetro, com malha de 10 mm. Foram capturados 865 espécimes, os quais foram analisados para estabelecer a razão sexual, que foi de 2,12 fêmeas por macho (χ² = 13,07; p<0,05). As fêmeas apresentaram crescimento alométrico positivo, enquanto que os machos foram alométricos negativos. Nas análises adicionais, as gônadas de 371 fêmeas foram observadas ao microscópio. O desenvolvimento gonadal foi classificado em três estádios: imaturo (5,0%), em maturação (12,0%) e maturo (83,0%). O desenvolvimento embrionário foi classificado em cinco fases, de acordo com o tamanho do embrião e do saco vitelino. A fecundidade média foi de 12 ovos / embriões por fêmea (variando de 1-37 ovos / embriões). Uma relação significativa foi verificada entre o comprimento padrão das fêmeas, o peso de seus ovários (R² = 0,257, p < 0,001), e o número de embriões (R² = 0,573, p < 0,001). O tamanho médio da primeira maturação sexual (L50) para as fêmeas foi estimado em 11,7 cm. A espécie se reproduz durante todo o ano.
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The main purpose of this paper is to explore health control beliefs (internality, powerful others, chance) in different age cohorts of elderly people and to examine the relationship between health control beliefs and objective and subjective health, and health behaviour. This contribution shows data from an interdisciplinary longitudinal ageing study: (a) a descriptive analysis of age- and time-correlated changes in health control beliefs of different cohorts of elderly people by taking into account gender as a differential aspect; (b) group comparisons between objectively and subjectively healthy or sick people and their health control beliefs and health relevant behaviour. Participants are 442 community elderly, 309 men, 133 women, aged 65± 94 years (mean age: 74.95 years). Our data demonstrate the dominance of chance control beliefs over internality and powerful others in all age cohorts. It can be concluded that internal control remains stable well into old age, whereas a signi® cant age-correlated increase of externality can be observed. Our results show the signi® cant relationship of subjective health self-evaluations with health control beliefs and health behaviour which is not the case for objective health parameters. Strong gender effects are found for internality and social externality: women have signi® cantly lower internality and powerful others scores than men.
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2016
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Obesity is a major public health problem in both developed and developing countries. The body mass index (BMI) is the most common index used to define obesity. The universal application of the same BMI classification across different ethnic groups is being challenged due to the inability of the index to differentiate fat mass (FM) and fat�]free mass (FFM) and the recognized ethnic differences in body composition. A better understanding of the body composition of Asian children from different backgrounds would help to better understand the obesity�]related health risks of people in this region. Moreover, the limitations of the BMI underscore the necessity to use where possible, more accurate measures of body fat assessment in research and clinical settings in addition to BMI, particularly in relation to the monitoring of prevention and treatment efforts. The aim of the first study was to determine the ethnic difference in the relationship between BMI and percent body fat (%BF) in pre�]pubertal Asian children from China, Lebanon, Malaysia, the Philippines, and Thailand. A total of 1039 children aged 8�]10 y were recruited using a non�]random purposive sampling approach aiming to encompass a wide BMI range from the five countries. Percent body fat (%BF) was determined using the deuterium dilution technique to quantify total body water (TBW) and subsequently derive proportions of FM and FFM. The study highlighted the sex and ethnic differences between BMI and %BF in Asian children from different countries. Girls had approximately 4.0% higher %BF compared with boys at a given BMI. Filipino boys tended to have a lower %BF than their Chinese, Lebanese, Malay and Thai counterparts at the same age and BMI level (corrected mean %BF was 25.7�}0.8%, 27.4�}0.4%, 27.1�}0.6%, 27.7�}0.5%, 28.1�}0.5% for Filipino, Chinese, Lebanese, Malay and Thai boys, respectively), although they differed significantly from Thai and Malay boys. Thai girls had approximately 2.0% higher %BF values than Chinese, Lebanese, Filipino and Malay counterparts (however no significant difference was seen among the four ethnic groups) at a given BMI (corrected mean %BF was 31.1�}0.5%, 28.6�}0.4%, 29.2�}0.6%, 29.5�}0.6%, 29.5�}0.5% for Thai, Chinese, Lebanese, Malay and Filipino girls, respectively). However, the ethnic difference in BMI�]%BF relationship varied by BMI. Compared with Caucasians, Asian children had a BMI 3�]6 units lower for a given %BF. More than one third of obese Asian children in the study were not identified using the WHO classification and more than half were not identified using the International Obesity Task Force (IOTF) classification. However, use of the Chinese classification increased the sensitivity by 19.7%, 18.1%, 2.3%, 2.3%, and 11.3% for Chinese, Lebanese, Malay, Filipino and Thai girls, respectively. A further aim of the first study was to determine the ethnic difference in body fat distribution in pre�]pubertal Asian children from China, Lebanon, Malaysia, and Thailand. The skin fold thicknesses, height, weight, waist circumference (WC) and total adiposity (as determined by deuterium dilution technique) of 922 children from the four countries was assessed. Chinese boys and girls had a similar trunk�]to�]extremity skin fold thickness ratio to Thai counterparts and both groups had higher ratios than the Malays and Lebanese at a given total FM. At a given BMI, both Chinese and Thai boys and girls had a higher WC than Malays and Lebanese (corrected mean WC was 68.1�}0.2 cm, 67.8�}0.3 cm, 65.8�}0.4 cm, 64.1�}0.3 cm for Chinese, Thai, Lebanese and Malay boys, respectively; 64.2�}0.2 cm, 65.0�}0.3 cm, 62.9�}0.4 cm, 60.6�}0.3 cm for Chinese, Thai, Lebanese and Malay girls, respectively). Chinese boys and girls had lower trunk fat adjusted subscapular/suprailiac skinfold ratio compared with Lebanese and Malay counterparts. The second study aimed to develop and cross�]validate bioelectrical impedance analysis (BIA) prediction equations of TBW and FFM for Asian pre�]pubertal children from China, Lebanon, Malaysia, the Philippines, and Thailand. Data on height, weight, age, gender, resistance and reactance measured by BIA were collected from 948 Asian children (492 boys and 456 girls) aged 8�]10 y from the five countries. The deuterium dilution technique was used as the criterion method for the estimation of TBW and FFM. The BIA equations were developed from the validation group (630 children randomly selected from the total sample) using stepwise multiple regression analysis and cross�]validated in a separate group (318 children) using the Bland�]Altman approach. Age, gender and ethnicity influenced the relationship between the resistance index (RI = height2/resistance), TBW and FFM. The BIA prediction equation for the estimation of TBW was: TBW (kg) = 0.231�~Height2 (cm)/resistance (ƒ¶) + 0.066�~Height (cm) + 0.188�~Weight (kg) + 0.128�~Age (yr) + 0.500�~Sex (male=1, female=0) . 0.316�~Ethnicity (Thai ethnicity=1, others=0) �] 4.574, and for the estimation of FFM: FFM (kg) = 0.299�~Height2 (cm)/resistance (ƒ¶) + 0.086�~Height (cm) + 0.245�~Weight (kg) + 0.260�~Age (yr) + 0.901�~Sex (male=1, female=0) �] 0.415�~Ethnicity (Thai ethnicity=1, others=0) �] 6.952. The R2 was 88.0% (root mean square error, RSME = 1.3 kg), 88.3% (RSME = 1.7 kg) for TBW and FFM equation, respectively. No significant difference between measured and predicted TBW and between measured and predicted FFM for the whole cross�]validation sample was found (bias = �]0.1�}1.4 kg, pure error = 1.4�}2.0 kg for TBW and bias = �]0.2�}1.9 kg, pure error = 1.8�}2.6 kg for FFM). However, the prediction equation for estimation of TBW/FFM tended to overestimate TBW/FFM at lower levels while underestimate at higher levels of TBW/FFM. Accuracy of the general equation for TBW and FFM compared favorably with both BMI�]specific and ethnic�]specific equations. There were significant differences between predicted TBW and FFM from external BIA equations derived from Caucasian populations and measured values in Asian children. There were three specific aims of the third study. The first was to explore the relationship between obesity and metabolic syndrome and abnormalities in Chinese children. A total of 608 boys and 800 girls aged 6�]12 y were recruited from four cities in China. Three definitions of pediatric metabolic syndrome and abnormalities were used, including the International Diabetes Federation (IDF) and National Cholesterol Education Program (NCEP) definition for adults modified by Cook et al. and de Ferranti et al. The prevalence of metabolic syndrome varied with different definitions, was highest using the de Ferranti definition (5.4%, 24.6% and 42.0%, respectively for normal�]weight, overweight and obese children), followed by the Cook definition (1.5%, 8.1%, and 25.1%, respectively), and the IDF definition (0.5%, 1.8% and 8.3%, respectively). Overweight and obese children had a higher risk of developing the metabolic syndrome compared to normal�]weight children (odds ratio varied with different definitions from 3.958 to 6.866 for overweight children, and 12.640�]26.007 for obese children). Overweight and obesity also increased the risk of developing metabolic abnormalities. Central obesity and high triglycerides (TG) were the most common while hyperglycemia was the least frequent in Chinese children regardless of different definitions. The second purpose was to determine the best obesity index for the prediction of cardiovascular (CV) risk factor clustering across a 2�]y follow�]up among BMI, %BF, WC and waist�]to�]height ratio (WHtR) in Chinese children. Height, weight, WC, %BF as determined by BIA, blood pressure, TG, high�]density lipoprotein cholesterol (HDL�]C), and fasting glucose were collected at baseline and 2 years later in 292 boys and 277 girls aged 8�]10 y. The results showed the percentage of children who remained overweight/obese defined on the basis of BMI, WC, WHtR and %BF was 89.7%, 93.5%, 84.5%, and 80.4%, respectively after 2 years. Obesity indices at baseline significantly correlated with TG, HDL�]C, and blood pressure at both baseline and 2 years later with a similar strength of correlations. BMI at baseline explained the greatest variance of later blood pressure. WC at baseline explained the greatest variance of later HDL�]C and glucose, while WHtR at baseline was the main predictor of later TG. Receiver�]operating characteristic (ROC) analysis explored the ability of the four indices to identify the later presence of CV risk. The overweight/obese children defined on the basis of BMI, WC, WHtR or %BF were more likely to develop CV risk 2 years later with relative risk (RR) scores of 3.670, 3.762, 2.767, and 2.804, respectively. The final purpose of the third study was to develop age�] and gender�]specific percentiles of WC and WHtR and cut�]off points of WC and WHtR for the prediction of CV risk in Chinese children. Smoothed percentile curves of WC and WHtR were produced in 2830 boys and 2699 girls aged 6�]12 y randomly selected from southern and northern China using the LMS method. The optimal age�] and gender�]specific thresholds of WC and WHtR for the prediction of cardiovascular risk factors clustering were derived in a sub�]sample (n=1845) by ROC analysis. Age�] and gender�]specific WC and WHtR percentiles were constructed. The WC thresholds were at the 90th and 84th percentiles for Chinese boys and girls, respectively, with sensitivity and specificity ranging from 67.2% to 83.3%. The WHtR thresholds were at the 91st and 94th percentiles for Chinese boys and girls, respectively, with sensitivity and specificity ranging from 78.6% to 88.9%. The cut�]offs of both WC and WHtR were age�] and gender�]dependent. In conclusion, the current thesis quantifies the ethnic differences in the BMI�]%BF relationship and body fat distribution between Asian children from different origins and confirms the necessity to consider ethnic differences in body composition when developing BMI and other obesity index criteria for obesity in Asian children. Moreover, ethnicity is also important in BIA prediction equations. In addition, WC and WHtR percentiles and thresholds for the prediction of CV risk in Chinese children differ from other populations. Although there was no advantage of WC or WHtR over BMI or %BF in the prediction of CV risk, obese children had a higher risk of developing the metabolic syndrome and abnormalities than normal�]weight children regardless of the obesity index used.
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The geometric mean regression equation for the weight; length relationship of Cynoglossus canariensis was W = 0.0025 L super(3.1770). The Von Bertalanffy constants Woo, Loo, K, and to were 507.5852 g, 47.3683 cm, 0.3333 and 0.1397 for males and 839.0753 g, 54.4720 cm, 0.3062 and 0.1737 for females. Total mortality coefficient Z ranged from 0.6482 and 0.8021
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Background:Research examining the relationship between adiponectin (AN) isoforms, body weight and cardiovascular (CV) risk factors is limited, particularly in younger populations. Objectives:To investigate the inter-relationships between AN isoforms and CV risk factors, and their dependence on body weight status, in adolescents. Design:Blood samples from 92 obese, 92 overweight and 92 normal weight age- and sex-matched adolescents were analysed for traditional cardiovascular disease (CVD) risk biomarkers and also total, high molecular weight (HMW), medium and low molecular weight (LMW) AN. Results:A significant inverse association was observed between total and HMW AN and waist-hip ratio (P=0.015, P=0.006, respectively), triglycerides (P=0.003, P=0.003, respectively) and systolic blood pressure (P=0.012, P=0.024, respectively) and a significant positive association with high-density lipoprotein (P<0.001, P<0.001, respectively) in multi-adjusted analyses. There was no evidence of a relationship between multimeric AN and high-sensitivity C-reactive protein. There was also little evidence of a relationship between LMW AN and CVD risk factors. There was a strong, body mass index (BMI)-independent, association between AN, CVD biomarkers and the hypertriglyceridemic waist phenotype. Conclusion:Prominent, BMI-independent associations between total and HMW AN, but not LMW AN, and CVD risk factors were already evident in this young population. This research in adolescents supports the contention that AN subfractions may have different biological actions. These associations in apparently healthy adolescents suggest an important role for AN and its subfractions in the pathogenesis of metabolic syndrome traits and indicate that the potential for total or HMW AN to act as early universal biomarkers of CV risk warrants further study.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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The biometric relationship between the weigth and the carapace width in the swimming crab A. cribrarius was compared with the results from other portunid crabs studied previously. During November/1988 to October/1989, a total of 403 specimens (189 males and 214 females) were collected with otter-trawl nets in north coast of the São Paulo State, Brazil. The animals were measured (carapace width excluding lateral spines = LC! and weighed (wet weight = PE). The empiric points of this relation were fit according to the power function (Y = a.X(b)) for each sex, maturation phases and total of individuals. The relation PE x LC indicates that the mole's growth changes during the ontogenesys from isometric (in juvenile phase) to allometric positive (in adult phase). For the females the growth is isometric in the two phases. The weight grows in a higher proportion than the carapace width variable (allometric positive growth). The data can be grouped in a single equation (PE = 7.85.10(-5).LC(3.14)) for the convertion between the variables there was a greater similarity between the equations obtained far each sex. In spite of this, the males present the fattening grade value (''a'') slightly higher than that of the females, possibly because of the greater size reached in its devellopment. The mean weight of the males is greater than the females one (p < 0.01). In the range 80 proves 90mm the males were more abundant, probably due to the females terminal ecdysis is near this size. The females only have the mean weight greater than the males in the 60 proves 70mm range (p < 0.01) when the puberty molt occurs and they present morphological changes in their reproductive system.
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The jumbo flying squid, Dosidicus gigas, support an important squid fishery off the Exclusive Economic Zone of Chilean waters. However, we only have limited information about their biology. In this study, age, growth and population structure of D. gigas were studied using statoliths from 333 specimens (386 females and 147 males) randomly sampled in the Chinese squid jigging surveys from 2007 to 2008 off the Exclusive Economic Zone of Chile. Mantle lengths (MLs) of the sample ranged from 206 to 702 mm, and their ages were estimated from 150 to 307 days for females and from 127 to 302 days for males. At least two spawning groups were identified, the main spawning peak tended to occur between August and November (austral spring group), and the secondary peak appeared during March to June (austral autumn group). The ML-age relationship was best modelled by a linear function for the austral spring group and a power function for the austral autumn group, and the body weight (BW)-age relationship was best described by an exponential function for both the groups. Instantaneous relative growth rates and absolute growth rates for ML and BW did not differ significantly between the two groups. The growth rate of D. gigas tended to be high at young stages, and then decreased after the sub-adult stage (>180 days old). This study suggests large spatial and temporal variability in key life history parameters of D. gigas, calling for the collection of more data with fine spatial and temporal scales to further improve our understanding of the fishery biology of D. gigas.
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Parameters a and b of the power body weight (W) - fecundity (F=a W super(b)) are presented for 25 populations comprising 15 species of Nigerian fishes. Estimates of b varied between 0.511 (Parauchenoglanis akin) and 1.654 (Periophthalmus barbarus) with a mean of 1.087 (s.d.=0.520). The maximum weight of populations examined did not significantly influence the relative magnitude of b. The parameters proportional to and beta of the linear weight-fecundity relationship (F= proportional to + beta W) are also presented for 27 fish populations from 22 species. Estimates of beta ranged from 4.22 (Chromidotilapia guntheri) to 2,062.94 (Pellunula min), with a mean of 243.80 (s.d.=477.89). The magnitude of beta declined with increasing maximum weights of fishes examined.
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Parameters a and b of the length (L)-weight (W) relationship W = a · Lb are presented for 17 commercial bivalve species collected from the southwest coastal waters of Korea. Estimates of b varied between 2.44 (Atrina pinnata japonica) and 3.31 (Scaphara broughtonii) with a mean of 2.891 (± 0.212). A total of 2 107 specimens were analyzed for this study. The length-weight relationship was isometric in most of the species.
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The red porgy, Pagrus pagrus, is an important reef fish in several offshore fisheries along the southeastern United States. We examined samples from North Carolina through southeast Florida from recreational (headboat) and commercial (hook and line) fisheries, as well as samples from a fishery-independent source. Red porgy attain a maximum age of at least 18 years and 733 mm total length. The weight-length relationship is represented by the ln-ln transformed equation: W = 8.85 × 10–6(L)3.06, where W = whole weight in grams, and L = total length in mm. The von Bertalanffy growth equation fitted to the most recent, back-calculated lengths from all the samples is Lt = 644(1 – e –0.15(t + 0.76)). Our study revealed a difference in mean length at age of red porgy from the three sources. Red porgy in fishery-independent collections were smaller at age than specimens examined from fishery-dependent sources. The difference in length-at-age may be related to gear selectivity and have important consequences in the assessment of fish stocks.