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1.
Objective: We examined relationships of eating patterns and reported energy intake (rEI) with BMI percentile in U.S. children. Research Methods and Procedures: Two 24‐hour dietary recalls from the Continuing Surveys of Food Intakes by Individuals 1994 to 1996 and 1998 (1005 boys, 990 girls) were averaged, and children were categorized into three age groups: 3 to 5 years (n = 1077), 6 to 11 years (n = 537), and 12 to 19 years (n = 381). Physiologically implausible reports due to reporting bias or abnormal intake (rEI outside ±18% to 23% of predicted energy requirements; pER) were identified. Results: rEI averaged 109 ± 34% and 100 ± 10% of pER in the total and plausible samples, respectively. EI was overreported more in younger children and underreported more in overweight older children. Children with plausible rEI (45.3% of sample) averaged 4.7 eating occasions/d, 589 kcal/meal, 223 kcal/snack, and 2038 kcal/d. rEI was not associated with BMI percentile in the total sample. In the plausible sample, rEI, meal portion size, and meal energy were positively associated with BMI percentile in boys 6 to 11 years and in children 12 to 19 years. No relationships were found in children 3 to 5 years and girls 6 to 11 years. Relationships were more consistent and stronger in the plausible compared with the total sample. Discussion: Excluding implausible dietary reports may be necessary for discerning dietary associations with BMI percentile. EI and meal, but not snack, patterns may play a quantitatively greater role in weight regulation as children age.  相似文献   

2.
Between 1998 and 2008, 621 Steller sea lions (Eumetopias jubatus, SSL) were captured underwater by SCUBA divers and anesthetized with isoflurane (n = 602) or sevoflurane (n = 19). We found significantly faster induction time ( ± SD) for sevoflurane (11 ± 6 min) compared to isoflurane (14 ± 6 min), as well as an interaction between anesthetists using the isoflurane protocol. Severe hypothermia with temperatures <35°C were measured in 22% of all animals, and had significant associations with month, length of anesthesia, and sex. Mortality rate was low (0.33%). We conclude that both isoflurane and sevoflurane anesthesia were effective for field anesthesia to safely handle and sample SSL.  相似文献   

3.
Objective: Higher levels of physical activity have been associated with body weight maintenance, but previous work in our laboratory suggests that this is not purely related to energy balance. We hypothesize that this may be related to the partitioning of dietary fat between oxidation and storage. Research Methods and Procedures: Healthy women (age 24 ± 1 years, BMI = 21.2 ± 0.4 kg/m2) were recruited to participate in rest (n = 10) or exercise sessions of light (n = 11), moderate (n = 10), and heavy (n = 7) exercise. All exercises (1250 kJ above rest) were performed on a stationary cycle inside of a whole‐body calorimeter. [1‐13C]oleate and [d31]palmitate were given in a liquid meal 30 minutes post‐exercise. An additional study was done with identical exercise sessions, but with administration of an oral dose of [1‐13C]acetate and [d3]acetate 30 minutes post‐exercise to determine label sequestration. Results: Cumulative oxidation of [1‐13C]oleate was significantly greater after light (45 ± 3%), moderate (54 ± 4%), and heavy (51 ± 4%) exercise than that with rest (33 ± 3%) (p = 0.0008). Cumulative oxidation of [d31]palmitate did not differ among trials (12 ± 2%, 14 ± 1%, 17 ± 2%, and 14 ± 2% for rest, light, moderate, and heavy, respectively; p = 0.30). Discussion: Exercise standardized for energy expenditure increases monounsaturated fat oxidation more than saturated fat oxidation and that the increase occurs regardless of intensity. Recommendations for physical activity for the purposes of weight control may be specific for dietary fat composition.  相似文献   

4.
Objective: The goal of this study was to determine whether differential induction of skeletal muscle uncoupling protein 3 (UCP3) contributes to the development of diet‐induced obesity (DIO) or resistance to the development of obesity (DR) when rats are placed on a moderate fat (31%) high energy (HE) diet. Research Methods and Procedures: Gastrocnemius muscle was obtained from Sprague‐Dawley rats that were identified as DIO‐prone (n = 5) or DR (n = 5) on the basis of urinary norepinephrine excretion while consuming a chow diet. Muscle was also obtained from animals in the top tertile of weight gain (DIOHE, n = 5) and the bottom tertile of weight gain (DRHE, n = 5) after 2 weeks on the HE diet. UCP3 and actin mRNA levels were measured in all muscle samples by Northern analysis. To distinguish the effect of dietary energy content from the effect of obesity itself, we studied additional DIO and DR animals that had been returned to a chow diet for 10 weeks after consuming a HE diet for 10 weeks. Results: The muscle UCP3/actin mRNA ratio in animals that resisted the development of obesity during 2 weeks on the HE diet was 3‐fold higher than in the other groups (DRHE = 3.24 ± 0.83, DIOHE = 0.91 ± 0.20, DIO‐prone = 0.72 ± 0.15, DR = 0.63 ± 0.15; p = 0.002). However, there was no difference in muscle UCP3/actin mRNA ratios between DIO animals and DR animals that had been fed the HE diet for 10 weeks and then returned to either an ad libitum chow diet for 10 weeks (DIO = 13.8 ± 3.53, DR = 11.1 ± 3.43, p = NS) or to a restricted chow diet for 10 weeks (DIO = 11.0 ± 2.85, DR = 10.6 ± 2.20, p = NS) despite significantly greater body weight of the DIO animals. Discussion: DR animals may initially resist weight gain when placed on a HE diet through a greater induction of muscle UCP3. This induction is transient and is related more closely to dietary fat content than to body fat stores. DIO animals show no initial induction of muscle UCP3, which may contribute to their increased metabolic efficiency soon after exposure to a HE diet.  相似文献   

5.
The aims of this study were to: describe dietary intakes of obese and nonobese middle-aged women using a validated food frequency questionnaire; to assess dietary restraint, disinhibition, and hunger by the three factor eating questionnaire (TFEQ) in obese and nonobese samples and determine which of the factors are independently associated with obesity; and to examine correlations between selected nutritional variables and the TFEQ factors. Subjects studied included 179 obese Swedish women (BMI>32) and 147 nonobese population-based controls (BMI<28). Age-adjusted mean energy intake was significantly higher in obese women (2730 ± 78 vs. 2025 ± 85 kcal, p<0.0001). In absolute and relative terms, fat intake was higher and alcohol intake was lower in the obese subjects. Disinhibition was the strongest TFEQ factor independently differentiating the obese and nonobese states, i.e., after adjustment for restraint and hunger. Within the obese sample, strong associations were seen between energy intake and disinhibition (p=0.0005) and hunger (p=0.0004). The association between energy intake and restrained eating was negative and weaker (p=0.04). No such associations were seen in nonobese women. Thus, using a dietary instrument that is valid and unbiased with respect to obesity, strong psychological correlates, possibly causal, of variability in energy intake were detected in middle-aged women with obesity. Disinhibition is associated with both obesity and high-energy intakes and is therefore an important factor to consider in the treatment of women with obesity.  相似文献   

6.
Objective: This study describes patterns of bias in self‐reported dietary recall data of girls by examining differences among girls classified as under‐reporters, plausible reporters, and over‐reporters on weight, dietary patterns, and psychosocial characteristics. Research Methods and Procedures: Participants included 176 girls at age 11 and their parents. Girls’ weight and height were measured. Three 24‐hour dietary recalls and responses to psychosocial measures were collected. Plausibility cut‐offs for reported energy intake as a percentage of predicted energy requirements were used to divide the sample into under‐reporters, plausible reporters, and over‐reporters. Differences among these three groups on dietary and psychosocial variables were assessed to examine possible sources of bias in reporting. Results: Using a ±1 standard deviation cut‐off for energy intake plausibility, 50% of the sample was categorized as plausible reporters, 34% as under‐reporters, and 16% as over‐reporters. Weight status of under‐reporters was significantly higher than that of plausible reporters and over‐reporters. With respect to reported dietary intake, under‐reporters were no different from plausible reporters on intakes of foods with higher nutrient densities and lower energy densities and were significantly lower than plausible reporters on intakes of foods with lower nutrient densities and higher energy densities. Over‐reporters reported significantly higher intakes of all food groups and the majority of subgroups, relative to plausible reporters. Under‐reporters had significantly higher levels of weight concern and dietary restraint than both plausible reporters and over‐reporters. Discussion: Techniques to categorize plausible and implausible reporters can and should be used to provide an improved understanding of the nature of error in children's dietary intake data and account for this error in analysis and interpretation.  相似文献   

7.
The vertical distribution of a bloom-forming Microcystis population was studied based on the relevant limnological parameters obtained from the lower Nakdong River (Mulgum) during the summer of 1994. Over three months (late June to late September), a high abundance of Microcystis population (mean ± SD, 2.9 ± 8.4 × 105 cells ml−1, n = 40) and algal biomass (mean ± SD, chlorophyll a, 131 ± 346 μg l−1, n = 31) was persistent throughout the entire water column (0–5 m, n = 11). The vertical distribution of carbon content was uneven, with a high concentration near the surface zone (mean ± SD, total, 7.9 ± 7.8; Microcystis, 5.2 ± 8.3 μg C ml−1, n = 15). Incorporating limnological and meteorological factors, a diel study of the vertical distribution of Microcystis showed that the chlorophyll a concentration was highest near the surface zone on a calm night (wind velocity, <2 m s−1, 2300–700) but was evenly distributed on a windy day (>4 m s−1, 1100–1900). Among many possible factors, wind velocity may have played an important role in controlling the vertical distribution of Microcystis in the lower Nakdong River. Received: July 12, 1999 / Accepted: November 15, 1999  相似文献   

8.
Methods are needed to assess exposure to genotoxins in humans and to improve understanding of dietary cancer prevention. The Comet assay was used to detect smoking-related exposures and dietary modulations in target tissues. Buccal scrapings, blood and faeces were collected from 38 healthy male volunteers (smokers and non-smokers) during a dietary intervention study with bread supplemented with prebiotics±antioxidants. GSTM1-genotype was determined with PCR. Buccal and peripheral lymphocytes were analysed for DNA damage using the Comet assay. Genotoxicity of faecal water (FW) was assayed in human colon HT29 clone 19A cells. ‘Tail intensity’ (TI) was used as a quantitative indicator of DNA damage in the Comet assay. Intervention with bread reduced DNA damage in lymphocytes of smokers (8.3±1.7% TI versus 10.2±4.1% TI, n=19), but not of non-smokers (8.6±2.8% TI versus 8.3±2.7% TI, n=15). Faecal water genotoxicity was reduced only in non-smokers (9.4±2.9% TI versus 18.9±13.1% TI, n=15) but not in smokers (15.5±10.7% TI versus 20.4±14.1% TI, n=13). The Comet assay was efficient in the detection of both smoking-related exposure (buccal cells) and efficacy of dietary intervention (faecal samples). Smokers and non-smokers profited differently from the intervention with prebiotic bread±antioxidants. Stratification of data by genotype enhanced specificity/sensitivity of the intervention effects and contributed important information on the role of susceptibility.  相似文献   

9.
Midlife women tend to gain weight with age, thus increasing risk of chronic disease. The purpose of this study was to examine associations between overweight/obesity and behavioral factors, including eating frequency, in a cross‐sectional national sample of midlife women (n = 1,099) (mean age = 49.7 years, and BMI = 27.7 kg/m2). Eating behaviors and food and nutrient intakes were based on a mailed 1‐day food record. BMI was calculated from self‐reported height and weight, and level of physical activity was assessed by self‐reported questionnaire. After exclusion of low‐energy reporters (32% of sample), eating frequency was not associated with overweight/obesity (P > 0.05) and was not different between BMI groups (normal, 5.21 ± 1.79; overweight, 5.16 ± 1.74; obese, 5.12 ± 1.68, P = 0.769). Adjusted logistic regression showed that eating frequency, snacking frequency, breakfast consumption, eating after 10 pm and consuming meals with children or other adults were not significantly associated with overweight/obesity. Total energy intake increased as eating frequency increased in all BMI groups, however, obese women had greater energy intake compared to normal weight women who consumed the same number of meals and snacks. Intake of fruit and vegetables, whole grains, dietary fiber, dairy, and added sugars also increased as eating frequency increased. While eating frequency was not associated with overweight/obesity, it was associated with energy intake. Thus, addressing total energy intake rather than eating frequency may be more appropriate to prevent weight gain among midlife women.  相似文献   

10.
We examined the accuracy of self‐reported energy intake (rEI) in low‐income, urban minority school‐aged children at risk for obesity and associated diabetes utilizing a relatively new, simple previously published prediction equation for identifying inaccurate reports of dietary energy intake. Participants included 614 nine‐year‐old boys (51%) and girls (49%). Three 24‐h dietary recalls were collected. Children's height, weight (used to calculate BMI), and percent body fat (%BF) were measured. Physical fitness, reported family history of diabetes, and ethnicity were also collected. A previously published prediction equation was used to determine the validity of rEIs in these children to identify under‐, plausible‐, and over‐reporters. Additionally, we examined the question of whether there is a difference in reporting by sex, ethnicity, BMI, and %BF. On average, 18% of the children were at risk of being overweight, 43% were already overweight at baseline, yet these children reported consuming fewer calories on average than recommended guidelines. Additionally, reported caloric intake in this cohort was negatively associated with BMI and %BF. Using the previously described methods, 49% of participants were identified as under‐reporters, whereas 39 and 12% were identified as plausible‐ and over‐reporters, respectively. On average, children reported caloric intakes that were almost 100% of predicted energy requirement (pER) when the sedentary category was assigned. Inactivity and excessive energy intake are important contributors to obesity. With the rising rates of obesity and diabetes in children, accurate measures of energy intake are needed for better understanding of the relationship between energy intake and health outcomes.  相似文献   

11.
Objective: To determine if overweight and obese women provide more accurate reports of their energy intake by 1) in‐person recall with an obese interviewer, 2) in‐person recall with a lean interviewer, or 3) telephone recall with an unknown interviewer. Research Methods and Procedures: Eighty‐eight overweight and obese women participated in this study. Subjects completed one telephone‐administered multiple‐pass 24‐hour recall (MP24R) with an unknown interviewer and were then randomly assigned to an in‐person MP24R with either a lean or obese interviewer to gather reported energy intake (rEI). Basal metabolic rate (BMR) was measured using a Deltrac monitor, and physical activity (EEPA) was estimated using a Caltrac accelerometer. Therefore, estimated energy expenditure was determined by: estTEE = (BMR + EEPA) × 1.10. Results: No significant differences were found between the two in‐person interview modes for subject age, weight, body mass index, percentage of body fat, total energy expenditure, rEI, and misreporting of energy intake. In‐person recall data were combined for comparison with the telephone recalls. No significant difference was found between the in‐person and telephone recalls for rEI and misreporting. Mean reported energy intake was significantly lower than estimated total energy expenditure for the telephone recalls and combined (lean and obese modes) in‐person recalls. Conclusions: This study found that interviewer body mass index had no impact on self‐reported energy intake during an in‐person MP24R, and that telephone recall data were comparable with in‐person recalls. Underreporting was a widespread problem (~26%) for all modes in this sample.  相似文献   

12.
Objective: Orlistat decreases the absorption of dietary triglycerides by inhibiting intestinal lipases. Orlistat therapy is associated with a greater decline in plasma low‐density lipoprotein‐cholesterol concentrations than that expected from weight loss alone. Therefore, we evaluated the effect of orlistat treatment on dietary cholesterol absorption as a possible mechanism for the independent effect of orlistat on plasma cholesterol concentration. Research Methods and Procedures: Cholesterol absorption from a standardized meal, containing 72 mg of cholesterol, was determined in 18 subjects with class II abdominal obesity (BMI, 35.0 to 39.9 kg/m2) by simultaneous administration of intravenous ([2H6] cholesterol) and oral ([2H5] cholesterol) cholesterol tracers. In protocol 1 (n = 9), cholesterol absorption was determined on two different occasions, 10 to 20 days apart, to assess the reproducibility of the tracer method. In protocol 2 (n = 9), cholesterol absorption was determined with and without orlistat therapy in a prospective, randomized, crossover design to assess the effect of orlistat on cholesterol absorption. Results: In protocol 1, cholesterol absorption from the test meal was the same on both occasions (53 ± 5% and 51 ± 5%). In protocol 2, orlistat treatment caused a 25% reduction in cholesterol absorption, from 59 ± 6% to 44 ± 5% (p < 0.01). Discussion: These data demonstrate that orlistat inhibits dietary cholesterol absorption, which may have beneficial effects on lipoprotein metabolism in obese subjects that are independent of weight loss itself.  相似文献   

13.
Abstract: Data on the behavior of walk-hunters and pointing dogs aids in understanding and managing quail harvest. We collected Global Positioning System track logs and recorded behaviors of hunters and dogs on northern bobwhite (Colinus virginianus) hunts in Oklahoma (n = 43), Texas (n = 43), and Missouri (n = 7), USA, during the 2005–2006 and 2006–2007 hunting seasons. Hunter velocity averaged 0.8 ± 0.03 (SE) m/second both seasons (n = 85) and pooled (95% CL overlap) velocity of bird dogs was 2.5 ± 0.07 (SE) m/second (n = 154). Hunters spent 60.5 ± 2.4% (SE) of their time walking in 2005–2006 (n = 45) versus 75.2 ± 3.5% (SE) in 2006–2007 (n = 48); respective figures for ranging by dogs were 50.2 ± 2.2% (n = 57) versus 82.0 ± 1.3% (SE; n = 97). Mean duration of a hunt declined from 82.3 ± 8.16 (SE) minutes (n = 45) to 50.2 ± 5.1 (SE) minutes (n = 48) between seasons. Variation in bobwhite abundance was the primary cause of seasonal variation in hunter and dog behaviors because covey-associated activities declined as quail abundance declined. With our results and those of previous workers, managers have first-generation estimates of all variables in hunter-covey interface models for managing bobwhite harvest on discrete areas.  相似文献   

14.
Objective: Isotope ratio mass spectrometry of hydrogen and oxygen is frequently used to determine total energy expenditure (TEE) using doubly labeled water. Conventionally, hydrogen isotope ratio is determined in hydrogen gas generated from water samples using zinc reduction. We compare this with a new automated platinum method to determine the ratios of hydrogen isotopes in deuterium‐enriched water samples. Research Methods and Procedures: The platinum method of sample preparation was compared with the zinc method in three ways: analytical variation in deuterium enrichment (within sample; n = 51), analytical variation in TEE estimates (within sample set; n = 10), and level of agreement of TEE estimates between both methods (n = 14). Results: For the zinc method, the standard deviation for multiple sets of triplicate 2H2O sample analysis was ±4.36‰ and ±2.07‰ for platinum. The correlation between TEE estimates when sample sets were analyzed in duplicate was r = 0.89 for zinc and r = 0.83 for platinum. The intercept and slope of the regression line were significantly different from the line of identity for duplicate TEE estimates by zinc but were not different from the line of identity for platinum. After correction for the intra‐assay variation of each method, the correlation between zinc and platinum for TEE was 0.77, and the intercept, but not the slope, of the regression was significantly different from the line of identity. The mean difference between the zinc method and the platinum method was 56 kcal/day, and the 95% confidence interval was ?438 to 550 kcal/day. Discussion: These data suggest that the platinum method is at least as reliable as the zinc method as a sample preparation technique for isotope ratio mass spectrometry of deuterium‐enriched water samples. The platinum method is also less costly and less labor‐intensive than the zinc method.  相似文献   

15.
Objective: Obstructive sleep apnea (OSA) is associated with obesity, sympathetic activation, systemic inflammation, and cardiovascular morbidity. Obesity, β‐adrenergic agonists, and inflammation are linked to decreased expression and/or secretion of an adipose tissue‐derived antiatherogenic hormone, adiponectin. The purpose of the study was to investigate whether OSA affected plasma levels of adiponectin, which might help explain OSA‐associated cardiovascular morbidity. Research Methods and Procedures: We randomly selected 68 otherwise healthy male subjects, either with moderate/severe OSA [apnea‐hypopnea index (AHI) ≥ 20; n = 35] or without OSA (AHI ≤ 5; n = 33). The diagnosis of OSA was made based on prospective full polysomnography. Adiponectin was measured before polysomnography between 8 and 10 PM . Results: AHI was higher in the OSA group (49.5 ± 4.4 vs. 2.9 ± 0.4 events/h; p < 0.001). OSA subjects were also more obese, with greater BMI (33 ± 1 vs. 30 ± 1; p = 0.016) and percentage body fat (29 ± 1% vs. 26 ± 1%; p = 0.030). Adiponectin levels were 7.67 ± 0.73 and 6.33 ± 0.51 μg/mL in the OSA and non‐OSA groups, respectively, and this difference was significant in covariate analysis (taking into account age, hemodynamic characteristics, measures of body fat, and OSA severity) (p = 0.009). After excluding from both groups the subjects with extreme BMI, such that the OSA and non‐OSA study cohorts had similar BMI and percentage body fat, subjects with OSA had significantly higher plasma adiponectin (8.49 ± 0.92 vs. 6.32 ± 0.55 μg/mL; p = 0.042), differences also evident in covariate analysis (p = 0.017). Discussion: Plasma adiponectin levels are elevated in otherwise healthy subjects with OSA. Therefore, low adiponectin is unlikely to explain the association between OSA and cardiovascular disease.  相似文献   

16.
Oxygen equilibrium curves and other respiratory-related variables were determined on blood from the flatback turtle (Natator depressus) and, for comparison, on some samples from the loggerhead turtle (Caretta caretta). The oxygen carrying capacity of the flatback turtle, 4.9–8.7 mmol l−1 (n = 49), is at the high end of the range in diving reptiles. Oxygen affinity (P50) was similar in both species at 5% CO2, ranging from 37 to 55 mmHg (43 mmHg ± 5.3 SD, n = 24, 25°C, pH 7.17) in flatbacks and 43–49 mmHg in loggerheads (46 mmHg ± 2.0 SD, n = 7, 25°C, pH 7.13), whereas at 2% CO2, flatbacks had a higher oxygen affinity. The curves differed in sigmoidicity, with Hill n coefficients of 2.8 and 1.9 in flatbacks and loggerheads, respectively. The Bohr effect was small in both the species, consistent with results from other sea turtles. Lactate levels were high, perhaps because the samples were taken from turtles coming ashore to lay eggs. Flatbacks are rarely found in waters deeper than 45 m. It is suggested that they have a respiratory physiology particularly suited to sustain prolonged shallow dives.  相似文献   

17.
The reduced form of ubiquinone-10 (coenzyme Q) has been shown to represent an important physiologic antioxidant principle in human blood. In order to establish a reference range for infants, we measured plasma levels of ubiquinone in 50 healthy European children aged 2 months to 15 years. A mean ±SD) value of 0.75±0.27 μg/ml plasma (0.87±0.31 μM) was determined; ubiquinone concentrations were not found to be sex-dependent (0.7±0.24μg/ml for girls, n=17, and 0.7±0.28μg/ml for boys, n=33) but correlated negatively with age (r = -0.37, P=0.0075). This negative correlation was mainly due to relatively high levels in infants approximately 1 year old.

The mean value determined does not significantly differ from the average ubiquinone plasma concentrations determined in healthy Nigerian children (0.85±0.40 μg/ml, n= 18) in a previous study (Becker K, Boetticher D, Leichsenring M. Internat J Vitam Nutr Res 1995, in press).  相似文献   

18.
Objective: The objective was to describe differences in weight loss, dietary intake, and cardiovascular risk factors between white and African‐American patients after gastric bypass (GBP). Research Methods and Procedures: This was a retrospective database review of a sample of 84 adult patients (24 African‐American and 60 white women and men) between the ages of 33 and 53 years. All subjects had GBP surgery in 2001 at the Bariatric Surgery Program at Boston Medical Center in Boston, MA, and were followed for one year postoperatively. Patients were excluded if weight data were missing at baseline, 3 months, or 1 year after GBP. A total of 9 African Americans and 41 whites provided data at all 3 time‐points and were included in the study. Differences in weight loss, diet, and cardiovascular risk factors were analyzed. Results: There were no differences in baseline characteristics between African Americans and whites. Mean weight loss for the entire sample was 36 ± 9%, with a range of 8% to 54% relative to initial body weight. Whites lost more weight (39 ± 8%) than African Americans (26 ± 10%) (p < 0.05). Dietary parameters, as well as improvements in blood pressure and lipid profiles, were similar in the two racial groups. Discussion: Differences in weight loss between severely obese African Americans and whites undergoing open GBP are unlikely to be related to postoperative dietary practices. Our data are consistent with previous reports implicating metabolic differences between the two racial groups.  相似文献   

19.
Rhipicephalus haemaphysaloides Supino, 1897 (Ixodida: Ixodidae) is a three‐host hard tick widely distributed in Sri Lanka. The lifecycle of the R. haemaphysaloides population in Sri Lanka was studied under laboratory conditions using fully engorged females collected from dogs. Larvae, nymphs and adults were reared on New Zealand rabbits. Engorged females weighed a mean ± standard deviation (SD) of 470.1 ± 106.5 mg and laid a mean ± SD of 4067.4 ± 3136.2 eggs within 16.1 ± 3.7 days. The mean ± SD preoviposition period was 6.5 ± 1.1 days. The mean ± SD reproductive efficiency index was 8.5 ± 4.1, and was higher in heavier females (Pearson correlation, r = 0.8; P = 0.001). The incubation period of eggs was shorter at higher temperatures. The majority (86.9%) of larvae successfully moulted after a mean ± SD premoulting period of 7.9 ± 0.7 days following a parasitic period of 3.2 ± 0.5 days. Unfed larvae survived a mean ± SD of 103.4 ± 19.8 days. Nymphs completed the bloodmeal after 3.7 ± 0.9 days, weighed 5.7 ± 1.7 mg and demonstrated a premoulting period of 15.1 ± 1.9 days. Unfed nymphs survived a mean ± SD of 45.8 ± 3.8 days. Heavier nymphs moulted into females, whereas lighter nymphs moulted into males (two‐sample t‐test, P < 0.001). The bodyweight of adult females increased more than 100‐fold after feeding. The lifecycle of R. haemaphysaloides was successfully completed on rabbits within a mean of 91.3 days (range: 69–117 days) under laboratory conditions.  相似文献   

20.
  • 1.1. Sulphate labelled proteoglycans (PG) synthesized by cultured human arterial smooth muscle cell have been quantified using an improved method based on a combination of specific enzymes and ethanol precipitation.
  • 2.2. The present method gives quantitative data of PGs and subclasses allowing batchwise analysis of a large number of samples.
  • 3.3. Approximately 81 % ± 1.7% (mean ± SD, n = 6) of total PGs synthesized by human arterial smooth muscle cells accumulated in medium.
  • 4.4. In cell layer and medium chondroitin sulphate proteoglycan constituted 65.0% ± 0.3% and 75.8% ± 0.7% (mean ± SD, n = 3), respectively of sulphated PGs.
  • 5.5. Heparan sulphate proteoglycan accounted for 26.8% ± 0.6% in cell layer and 22.6% ± 0.5% (mean ± SD, n = 3) in medium of sulphated PGs.
  相似文献   

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