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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
121

Perzentile für den Body-mass-Index für das Kindes- und Jugendalter unter Heranziehung verschiedener deutscher Stichproben

Kromeyer-Hauschild, Katrin, Wabitsch, M., Kunze, D., Geller, F., Geiß, H. C., Hesse, V., von Hippel, A., Jaeger, U., Johnsen, D., Korte, W., Menner, K., Müller, G., Müller, J. M., Niemann-Pilatus, A., Remer, T., Schaefer, F., Wittchen, Hans-Ulrich, Zabransky, S., Zellner, K., Ziegler, A., Hebebrand, J. January 2001 (has links)
Fragestellung: Sowohl die Childhood Group der International Obesity Task Force (IOTF) als auch die European Childhood Obesity Group (ECOG) empfehlen den Body-mass-Index als Beurteilungskriterium für Übergewicht und Adipositas bei Kindern und Jugendlichen. Im Erwachsenenalter erfolgt die Definition von Übergewicht und Adipositas anhand fester Grenzwerte, bei der Beurteilung von Kindern und Jugendlichen müssen die alters- und geschlechtsspezifischen Veränderungen des BMI berücksichtigt werden. Methode: Unter Heranziehung von 17 bereits durchgeführten Untersuchungen aus verschiedenen Regionen Deutschlands wurden BMI-Perzentile für Kinder und Jugendliche erstellt. Die Berechnung der Perzentile basiert auf den Körperhöhen- und Körpergewichtsdaten von 17.147 Jungen und 17.275 Mädchen im Alter von 0–18 Jahren. Ergebnisse und Schlussfolgerung: Die vorgestellten Perzentile sollten als Referenz für deutsche Kinder und Jugendliche angewendet werden. Die Arbeitsgemeinschaft „Adipositas im Kindes- und Jugendalter“ (AGA) hat in ihren Leitlinien die Anwendung der hier vorgestellten 90. und 97. Perzentile zur Definition von Übergewicht und Adipositas empfohlen. / Objectives: Both the Childhood Group of the International Obesity Task Force (IOTF) and the European Childhood Obesity Group (ECOG) recommend to use the body mass index (BMI = weight in kilograms/height in meter2) to evaluate overweight and obesity in children and adolescents. Whereas it is customary with adults to use fixed cut off points to define overweight and obesity, in children and adolescents age and sex specific developmental changes in BMI need to be addressed, which are due to physiological alterations of fat mass. Method: Because a national reference population for children and adolescents does not exist in Germany, a BMI reference data set was compiled. Therefore measurements of height and weight from 17 different regional studies including 17147 boys and 17275 girls aged 0 to 18 years were used. Results and conclusions: We recommend the use of the presented percentiles as reference to asses under- and overweight (obesity) in German children and adolescents. In the guidelines of the “Arbeitsgruppe Adipositas im Kindes- und Jugendalter”(AGA) the 90th and 97th BMI percentiles as calculated in this reference population are proposed as cut-off points for the definition of overweight and obesity in German children and adolescents.
122

Profile of selected cardiovascular disease risk factors among HIV patients on anti-retroviral therapy in Bushbuckridge Sub-District, Mpumalanga Province

Mathebula, Rudy Londile January 2019 (has links)
Thesis (MPH.) -- University of Limpopo, 2019 / The purpose of this study was to profile selected cardiovascular disease risk factors among HIV patients on ART in Bushbuckridge sub-district. Quantitative, crosssectional research was conducted to describe cardiovascular disease risk factors among HIV patients on ART in Bushbuckridge Sub-district. Data collection was done using researcher-administered questionnaires. Adult HIV patient on ART participated in the study (n=328). The study has highlighted cardiovascular disease risk factors and prevalence of cardiovascular disease risk factors among HIV patients on ART. The findings revealed the prevalence of hypertension is 34.6% among HIV patients on ART and men had a higher prevalence compared to women. There is an increase in body mass index and it is seen mostly among women. Alcohol consumption is highest in the young adults (18 to 24 years) both men and women. Health promotion and policymaking interventions need to improve strategies on management and prevention of cardiovascular disease risk factors. Key concepts HIV, ART, cardiovascular disease risk factors, prevalence, body mass index, Bushbuckridge
123

Obesity and associated lifestyle in a large sample of multi-morbid German primary care attendees

Sikorski, Claudia, Luppa, Melanie, Weyerer, Siegfried, König, Hans-Helmut, Maier, Wolfgang, Schön, Gerhard, Petersen, Juliane J., Gensichen, Jochen, Fuchs, Angela, Bickel, Horst, Wiese, Birgitt, Hansen, Heike, van den Bussche, Hendrik, Scherer, Martin, Riedel-Heller, Steffi G. January 2014 (has links)
Background: Obesity and the accompanying increased morbidity and mortality risk is highly prevalent among older adults. As obese elderly might benefit from intentional weight reduction, it is necessary to determine associated and potentially modifiable factors on senior obesity. This cross-sectional study focuses on multi-morbid patients which make up the majority in primary care. It reports on the prevalence of senior obesity and its associations with lifestyle behaviors. Methods: A total of 3,189 non-demented, multi-morbid participants aged 65–85 years were recruited in primary care within the German MultiCare-study. Physical activity, smoking, alcohol consumption and quantity and quality of nutritional intake were classified as relevant lifestyle factors. Body Mass Index (BMI, general obesity) and waist circumference (WC, abdominal obesity) were used as outcome measures and regression analyses were conducted. Results: About one third of all patients were classified as obese according to BMI. The prevalence of abdominal obesity was 73.5%. Adjusted for socio-demographic variables and objective and subjective disease burden, participants with low physical activity had a 1.6 kg/m2 higher BMI as well as a higher WC (4.9 cm, p<0.001). Current smoking and high alcohol consumption were associated with a lower BMI and WC. In multivariate logistic regression, using elevated WC and BMI as categorical outcomes, the same pattern in lifestyle factors was observed. Only for WC, not current but former smoking was associated with a higher probability for elevated WC. Dietary intake in quantity and quality was not associated with BMI or WC in either model. Conclusions: Further research is needed to clarify if the huge prevalence discrepancy between BMI and WC also reflects a difference in obesity-related morbidity and mortality. Yet, age-specific thresholds for the BMI are needed likewise. Encouraging and promoting physical activity in older adults might a starting point for weight reduction efforts.
124

Assoziation zwischen der Besiedlung mit Helicobacter pylori im Kindesalter und dem Body-Mass-Index

Reichel, Anne 05 February 2014 (has links)
Diese Dissertation befasst sich mit den möglichen Folgen einer Kolonisation mit Helicobacter pylori (H. pylori) im Kindesalter. Von besonderem Interesse ist dabei die Entwicklung des Body-Mass-Index (BMI). Dazu werden die Daten einer populationsbezogenen Querschnittsstudie, welche 1998 und 2006 unter Leipziger Schulanfängern bzw. Achtklässlern durchgeführt wurde, analysiert. Insgesamt konnten 1349 bzw. 1161 Kinder, deren H. pylori-Status mittels 13C‑Harnstoff-Atemtest untersucht wurde, in die Untersuchung inkludiert werden. Dabei bestätigte sich, dass die Besiedlung mit H. pylori u.a. signifikant mit einem geringeren sozialen Status und einer geringeren Körpergröße der Kinder assoziiert ist. Der BMI der untersuchten Kinder unterscheidet sich jedoch nicht signifikant in Abhängigkeit von einer Kolonisation mit H. pylori. Auf diesen Ergebnissen basierend werden zwei Hypothesen diskutiert. Zum einen wird analysiert, inwieweit ein Einfluss einer Infektion mit dem Erreger auf den BMI der Kinder nicht sicher auszuschließen ist und dieser eventuell aufgrund der Komplexität der Gewichtsentwicklung in den Ergebnissen dieser Untersuchung nicht erkennbar ist. Zum anderen wird die geringere Körpergröße H. pylori‑besiedelter Kinder nicht auf mit der Infektion in Verbindung stehende Ernährungsstörungen in Zusammenhang gebracht, da sonst vor einer entscheidenden Größenminderung das Gewicht bzw. der BMI der Studienteilnehmer zurück bleiben müsste.
125

Sexuální dysfunkce u obézních žen po bariatrické léčbě obezity. / Sexual Dysfunction in the Obese Female after Bariatric Surgery.

Pichlerová, Dita January 2019 (has links)
6 Abstract Background: Obesity and associated comorbidities increase the probability of sexual disorders. We aimed to assess sexual satisfaction in obese women before and after bariatric surgery using the validated Female Sexual Function Index (FSFI) and also to assess sexual satisfaction in obese women in comparison with women of normal weight. We also compared the frequency of female sexual dysfunction (FSD) of the participants. Methods: 60 obese women 5.99 completed the questionnaire on sexual satisfaction (FSFI) before a bariatric procedure (laparoscopic adjustable gastric banding, 22 women; gastric plication, 33 women; and biliopancreatic diversion, 5 women), 6 months and 12 months after the procedure, i.e. after a significant weight reduction (final BMI of . The control group consisted of 60 women of normal weight (mean BMI of 22.2 1.9 domains, with higher scores indicating better sexual function. The FSFI total score (range 2- dicating FSD. Results: Baseline sexual function in the preoperative obese female was significantly lower than in the control group of women of normal weight (p < 0.01) in each domain. Average postoperative FSFI scores increased from preoperative levels in all domains, but significant improvement occurred only in the domain for desire (p < 0.01). The results at 6 and 12 months...
126

High Cholesterol, Triglycerides, and Body-Mass Index in Suicide Attempters

Brunner, Jürgen, Bronisch, Thomas, Pfister, Hildegard, Jacobi, Frank, Höfler, Michael, Wittchen, Hans-Ulrich January 2006 (has links)
Low cholesterol concentrations and cholesterol-lowering therapies have been suggested to be associated with increased suicidality. This article examined the association of cholesterol, triglycerides, and body-mass index (BMI) with suicidal ideation and suicide attempts. Findings are based on a nationally representative community sample of n = 4,181 subjects (18–65 years) examined with a standardized diagnostic interview (CIDI) for (DSM-IV) mental disorders. Controlling for age and gender the study revealed a moderate positive association between cholesterol, triglycerides, BMI, and suicide attempts in subjects with depressive symptoms during the past 12 months (n = 1,205). The results of this study are compatible with two recent epidemiological cohort studies showing a positive association between cholesterol and completed suicide.
127

Associations between specific measures of adiposity and high blood pressure in black South African women / Maretha Doubell

Doubell, Maretha January 2015 (has links)
Introduction: The World Health Organisation (WHO) defines overweight and obesity as a condition in which an abnormal or excessive fat accumulation exists to an extent in which health and well-being are impaired. The most recent South African National Health and Nutrition Examination Survey (SANHANES) reported that the prevalence of overweight and obesity, according to body mass index (BMI) classification, in all South African women was significantly higher than in men (24.8% and 39.2% compared to 20.1% and 10.6% for women and men, respectively). Blood pressure is often increased in obese patients and is probably the most common co-morbidity associated with obesity. Currently approximately one third (30.4%) of the adult South African population has hypertension. Hypertension is responsible for a significant percentage of the high rates of cardiovascular disease and stroke in South Africa. Limited South African data are available regarding the agreement between the measures of adiposity, including BMI, waist circumference (WC) and percentage body fat (%BF), and the association with high blood pressure. Measures of adiposity were found in previous research to be ethnicity, age and gender specific. Measuring %BF to classify adiposity takes body composition into account and is a more physiological measurement of obesity than BMI. Objective: This study aimed to investigate the agreement between adiposity classified by BMI categories and %BF cut-off points, and the association between the different measures of adiposity and high blood pressure. Method: A representative sample of black women (n=435), aged 29 years to 65 years from Ikageng in the North West Province of South Africa were included in this cross-sectional epidemiological study. Socio-demographic questionnaires were completed. Pregnancy and HIV tests were performed and those with positive test results or those who declined HIV testing were excluded. Weight and height were measured and BMI was calculated. WC, %BF using dual-energy X-ray absorptiometry (DXA), and blood pressure were measured. Results: The prevalence of overweight (BMI 25.0 kg/m² – 29.9 kg/m²) was 24.4% and obesity (BMI ≥ 30kg/m²) was 52.4%. High blood pressure was found to be present in more than two thirds of the study participants (68.5%). In this study BMI, WC and %BF as measures of adiposity were significantly correlated. There were significant agreements between combined overweight/obesity that was defined by %BF (≥35.8% 29-45 years; ≥37.7% ≥50 years) and BMI ≥ 25kg/m² (ᵡ²=199.0, p<0.0001; κ=0.68, p<0.0001), and between the presence of high %BF and obesity only, that was defined by BMI ≥ 30 kg/m² (ᵡ²=129.1, p<0.0001; κ=0.48, p<0.0001). The effect size of the agreement between the WHO BMI category for combined overweight/obesity and %BF cut-off points according to the kappa value of κ=0.68 was substantial (κ range 0.61-0.80). The effect size of the agreement between the WHO BMI category for obesity only and %BF cut-off points according to the kappa value of κ=0.48 was moderate (κ range 0.41-0.60). No association was found between high blood pressure and BMI categorised combined overweight/obesity (ᵡ²=3.19; p=0.74), but a significant association was found between high blood pressure and BMI categorised obesity only (ᵡ²=4.10; p=0.043). A significantly increased odds ratio (OR) of high blood pressure existed in the obesity BMI category (OR=1.52; p=0.045) as opposed to the overweight/obesity BMI category (OR=1.51; p=0.075). There were significant associations between high blood pressure and WC ≥ 80cm (ᵡ²=10.9; p=0.001; OR=2.08; p=0.001), WC ≥ 92cm (ᵡ²=20.1; p<0.0001; OR=1.79; p=0.011) and %BF above the age-specific cut-off points (ᵡ²=6.61; p=0.010; OR=1.70; p=0.011). Discussion and conclusion: This study found that in a sample of black urban South African women significant agreements existed between adiposity defined by %BF cut-off points for combined overweight/obesity and both WHO BMI categorised combined overweight/obesity (BMI ≥ 25 kg/m2) and obesity only (BMI ≥ 30 kg/m2), respectively. A stronger agreement was found between WHO categorised combined overweight/obesity and %BF. Furthermore, this study concluded that the BMI category according to the WHO cut-off point for overweight/obesity had insufficient sensitivity to detect the presence of high blood pressure, and that the BMI category according to the WHO cut-off point for obesity alone could detect the presence of high blood pressure. The WHO BMI classification for obesity, in contrast to the WHO BMI classification for combined overweight/obesity, is therefore appropriate to classify these black South African women at increased risk for high blood pressure. The WC and %BF cut-off points used which were specific to ethnicity, age and gender, had significant associations with high blood pressure and have good capacity to detect high blood pressure. In this study abdominal obesity as defined by the South African cut-off point of WC ≥ 92 cm had a stronger association with high blood pressure, than the international cut-off point (WC ≥ 80 cm). The South African cut-off point is, therefore, more appropriate to screen black South African women for increased risk for high blood pressure. The study therefore concluded that a stronger agreement was found between WHO categorised combined overweight/obesity and %BF than with obesity only (BMI ≥ 30 kg/m2). To ensure consistency and accuracy, and to take body composition into consideration, it is recommended that, where possible, in clinical practice the appropriate WC and %BF cut-off points together with BMI categories should be used as measures of adiposity for diagnosis of overweight and obesity and to screen or detect an increased risk for high blood pressure. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2015
128

Associations between specific measures of adiposity and high blood pressure in black South African women / Maretha Doubell

Doubell, Maretha January 2015 (has links)
Introduction: The World Health Organisation (WHO) defines overweight and obesity as a condition in which an abnormal or excessive fat accumulation exists to an extent in which health and well-being are impaired. The most recent South African National Health and Nutrition Examination Survey (SANHANES) reported that the prevalence of overweight and obesity, according to body mass index (BMI) classification, in all South African women was significantly higher than in men (24.8% and 39.2% compared to 20.1% and 10.6% for women and men, respectively). Blood pressure is often increased in obese patients and is probably the most common co-morbidity associated with obesity. Currently approximately one third (30.4%) of the adult South African population has hypertension. Hypertension is responsible for a significant percentage of the high rates of cardiovascular disease and stroke in South Africa. Limited South African data are available regarding the agreement between the measures of adiposity, including BMI, waist circumference (WC) and percentage body fat (%BF), and the association with high blood pressure. Measures of adiposity were found in previous research to be ethnicity, age and gender specific. Measuring %BF to classify adiposity takes body composition into account and is a more physiological measurement of obesity than BMI. Objective: This study aimed to investigate the agreement between adiposity classified by BMI categories and %BF cut-off points, and the association between the different measures of adiposity and high blood pressure. Method: A representative sample of black women (n=435), aged 29 years to 65 years from Ikageng in the North West Province of South Africa were included in this cross-sectional epidemiological study. Socio-demographic questionnaires were completed. Pregnancy and HIV tests were performed and those with positive test results or those who declined HIV testing were excluded. Weight and height were measured and BMI was calculated. WC, %BF using dual-energy X-ray absorptiometry (DXA), and blood pressure were measured. Results: The prevalence of overweight (BMI 25.0 kg/m² – 29.9 kg/m²) was 24.4% and obesity (BMI ≥ 30kg/m²) was 52.4%. High blood pressure was found to be present in more than two thirds of the study participants (68.5%). In this study BMI, WC and %BF as measures of adiposity were significantly correlated. There were significant agreements between combined overweight/obesity that was defined by %BF (≥35.8% 29-45 years; ≥37.7% ≥50 years) and BMI ≥ 25kg/m² (ᵡ²=199.0, p<0.0001; κ=0.68, p<0.0001), and between the presence of high %BF and obesity only, that was defined by BMI ≥ 30 kg/m² (ᵡ²=129.1, p<0.0001; κ=0.48, p<0.0001). The effect size of the agreement between the WHO BMI category for combined overweight/obesity and %BF cut-off points according to the kappa value of κ=0.68 was substantial (κ range 0.61-0.80). The effect size of the agreement between the WHO BMI category for obesity only and %BF cut-off points according to the kappa value of κ=0.48 was moderate (κ range 0.41-0.60). No association was found between high blood pressure and BMI categorised combined overweight/obesity (ᵡ²=3.19; p=0.74), but a significant association was found between high blood pressure and BMI categorised obesity only (ᵡ²=4.10; p=0.043). A significantly increased odds ratio (OR) of high blood pressure existed in the obesity BMI category (OR=1.52; p=0.045) as opposed to the overweight/obesity BMI category (OR=1.51; p=0.075). There were significant associations between high blood pressure and WC ≥ 80cm (ᵡ²=10.9; p=0.001; OR=2.08; p=0.001), WC ≥ 92cm (ᵡ²=20.1; p<0.0001; OR=1.79; p=0.011) and %BF above the age-specific cut-off points (ᵡ²=6.61; p=0.010; OR=1.70; p=0.011). Discussion and conclusion: This study found that in a sample of black urban South African women significant agreements existed between adiposity defined by %BF cut-off points for combined overweight/obesity and both WHO BMI categorised combined overweight/obesity (BMI ≥ 25 kg/m2) and obesity only (BMI ≥ 30 kg/m2), respectively. A stronger agreement was found between WHO categorised combined overweight/obesity and %BF. Furthermore, this study concluded that the BMI category according to the WHO cut-off point for overweight/obesity had insufficient sensitivity to detect the presence of high blood pressure, and that the BMI category according to the WHO cut-off point for obesity alone could detect the presence of high blood pressure. The WHO BMI classification for obesity, in contrast to the WHO BMI classification for combined overweight/obesity, is therefore appropriate to classify these black South African women at increased risk for high blood pressure. The WC and %BF cut-off points used which were specific to ethnicity, age and gender, had significant associations with high blood pressure and have good capacity to detect high blood pressure. In this study abdominal obesity as defined by the South African cut-off point of WC ≥ 92 cm had a stronger association with high blood pressure, than the international cut-off point (WC ≥ 80 cm). The South African cut-off point is, therefore, more appropriate to screen black South African women for increased risk for high blood pressure. The study therefore concluded that a stronger agreement was found between WHO categorised combined overweight/obesity and %BF than with obesity only (BMI ≥ 30 kg/m2). To ensure consistency and accuracy, and to take body composition into consideration, it is recommended that, where possible, in clinical practice the appropriate WC and %BF cut-off points together with BMI categories should be used as measures of adiposity for diagnosis of overweight and obesity and to screen or detect an increased risk for high blood pressure. / MSc (Dietetics), North-West University, Potchefstroom Campus, 2015
129

Chemical characterisation of the uropygial secretion of Rhinopomastus cyanomelas

Ghebrealfa Kahsai, Negassi 03 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2004. / ENGLISH ABSTRACT: The uropygial gland of most birds produces a variety of hydrocarbons, lipids, waxes, fatty acids, alcohols and other organic compounds. These compounds have two widely recognized functions, viz. they are considered essential for the maintenance of a good plumage condition, and may be used for fungicidal, bactericidal or other hygienic purposes. Scimitar-billed woodhoopoes, Rhinopomastus cyanomelas, are groupterritorial birds that live in groups comprising between two and twelve individuals. Individuals enter the roost cavities shortly after sunset and exit the following morning soon after sunrise. During the period that the birds are inside the roost, they are vulnerable to a range of vertebrate predators, including snakes, genets and rats. When disturbed while roosting, woodhoopoes immediately face away from the threat hence presenting their uropygial glands in the direction of the threat. Typically, a drop of brown, highly pungent secretion is then formed at the tip of the papilla to the uropygial gland, and kept in place by a few tuft-like feathers. This response pattern has led some observers to believe that the secretion serves an anti-predatory role. It has been found that the synthetic volatile constituents of the uropygial secretion of the green woodhoopoe, P. purpureus, individually or as a mixture, have potent defensive properties against feline and reptilian predators. In addition, the compounds also showed activity against a range of bacteria. The aim of the present study was to determine the chemical composition of the uropygial secretion of the scimitar-billed woodhoopoe, Rhinopomastus cyanomelas, as a first step towards the evaluation of, inter alia, the semiochemical function of the secretion. Using gas chromatography-mass spectrometry, 179 constituents of the uropygial secretion of the scimitar-billed woodhoopoe have been identified. The majority of the constituents of the secretion are branched and unbranched aldehydes (aliphatic and aromatic), acids (aliphatic and aromatic), sulfides and ketones. This group of volatile compounds is responsible for the obnoxious odour of the secretion and possibly also for its defensive action against predators. The secretion also contains a large number of branched and unbranched alkanes and wax esters. The chemical composition of the secretion was compared with the secretion of P. purpureus as well as with that of the hoopoe, Upupa africana. The uropygial gland secretion of the scimitar-billed woodhoopoe is quite similar to that of the green woodhoopoe, although it is much more complex than that of the green woodhoopoe. In contrast to the uropygial secretions of the green and the scimitar-billed woodhoopoes, the secretion of Upupa africana does not have a strongly obnoxious odour and it also does not contain large quantities of alkanes and wax esters. / AFRIKAANSE OPSOMMING: Die uropigiale klier van die meeste voëls produseer 'n verskeidenheid van koolwaterstowwe, lipiede, was-esters, vetsure, alkohole en ander organiese verbindings. Hierdie verbindings het twee algemeen erkende funksies, naamlik die instandhouding van die goeie kondisie van die vere, en 'n swam- en kiemdodende werking. Swartbekkakelaars (Engels: scimitar-billed woodhoopoes ), Rhinopomastus cyanomelas, is groep-territoriale voëls wat in groepe van tussen twee en twaalf saam woon. Individue gaan hul neste net na sononder binne en verlaat dit weer die volgende oggend net na sonsopkoms. Terwyl die voëls binne die neste is, is hulle kwesbaar ten opsigte van aanval deur verskeie gewerwelde roofdiere, insluitende slange, muskeljaatkatte en rotte. Wanneer hulle in hul neste gesteur word, sal kakelaars onmiddellik wegdraai van die bedreiging sodat die uropigiale klier in die rigting van die bedreiging gekeer is. 'n Druppel bruin, uiters onwelriekende afskeiding vorm dan by die punt van die papil na die uropigiale klier, en word in posisie gehou deur 'n verekwassie. Hierdie gedragspatroon het aanleiding gegee tot die gedagte by sommige waarnemers dat die afskeiding as afweerstof teen roofdiere dien. Daar is gevind dat die sintetiese vlugtige komponente van die uropigiale afskeiding van die groenkakelaar, P. purpureus, individueel of as 'n mengsel, sterk afweer-eienskappe teen katte en reptiele toon. Daarbenewens het die verbindings ook aktiwiteit getoon teen 'n reeks van bakterieë. Die doel van die huidige studie was om die chemiese samestelling van die uropigiale afskeiding van die swartbekkakelaar, Rhinopomastus cyanomelas, te bepaal as 'n eerste stap met die oog op die evaluering van, onder andere, die semiochemiese funksie van die afskeiding. Deur van gaschromatografie-massaspektrometrie gebruik te maak, is 179 komponente van die uropigiale afskeiding van die swartbekkakelaar geïdentifiseer. Die meeste van die komponente is vertakte en onvertakte aldehiede (alifaties en aromaties), sure (alifaties en aromaties), sulfiede en ketone. Hierdie groep vlugtige verbindings is verantwoordelik vir die afstootlike reuk van die afskeiding en waarskynlik ook vir sy afweer-aksie teen roofdiere. Die afskeiding bevat ook 'n groot aantal vertakte en onvertakte alkane en wasesters. Die chemiese samestelling van die afskeiding is vergelyk met die van P. purpureus sowel as dié van die hoepoe, Upupa africana. Die uropigiale klierafskeiding van die swartbekkakelaar stem tot 'n groot mate ooreen met dié van die groenkakelaar, alhoewel dit veel meer kompleks is as dié van die groenkakelaar. In teenstelling met die uropigiale afskeidings van die groen- en die swartbekkakelaars, het die afskeiding van Upupa africana nie 'n afstootlike reuk nie en bevat dit ook nie groot hoeveelhede alkane en was-esters nie.
130

Dietary behaviour and body mass index in Hong Kong school children

Chan, Wai-kei, Victoria, 陳慧琪 January 2005 (has links)
published_or_final_version / Community Medicine / Master / Master of Public Health

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