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21.
Jamie Dollahite Wene George M. Barnwell Daniel S. Mitchell 《Physiology & behavior》1982,28(3):569-573
To evaluate the influence of flavor on ad lib consumption and on associated changes in body weight, female baboons, 7–15 years of age, served in two experiments with seven monkey chows which were identical except for flavor: lemon, orange, apple, sugar, fruit punch, chocolate, and unflavored. In the first experiment, two groups of animals (n=7 and 4) received five of the seven flavors, presented in daily pair-wise combinations. Analysis of quantities consumed demonstrated marked and consistent flavor preferences in individual baboons. Although specific preference varied between animals, total amounts consumed of the various flavors differed significantly, with rank ordering clearly evident. Overall food intake and body weights increased significantly over baseline values obtained with a standard, unflavored chow. In the second experiment, three baboons received chow of a preferred flavor for nine weeks. Amounts consumed and body weights increased significantly over baseline. These results indicate that flavored chows may be useful for producing a nonhuman primate behavioral model of obesity and for inducing animals to eat otherwise unpalatable diets. 相似文献
22.
目的探讨日常琐事应激与大学生健康的关系,检验日常琐事应激对健康的预测作用。方法采用自测健康量表和经修订的日常琐事应激量表对153名大学生施测,考察自测健康和日常琐事应激的关系。结果大学生日常琐事应激频率对生理健康预测显著;认知评价和个体应对对心理健康预测显著;个体应对对社会健康预测显著;应激频率和个体应对对总体健康预测显著。结论大学生日常琐事应激与健康关系密切,可作为预测个体身心健康的有效预测源。 相似文献
23.
Ultrasound-guided in utero injections into the brain of murine embryos has been shown to facilitate gene delivery. We investigated whether these methods would allow gene transfer into ocular structures. Gene transfer using retroviral vectors or electroporation was found to be quite effective. We determined the window of time, as well as compared several strains of mice, that yield a high degree of survival and successful gene transfer. Several retroviral constructs were tested for expression and coexpresssion of two genes in retinal cell types. In addition, a retroviral vector was engineered to give cone photoreceptor-enriched expression, and a retroviral vector was demonstrated to provide RNAi-mediated loss-of-function. These methods enable access to early ocular structures and provide a more rapid method of assessment of gene and promoter function than possible using genetically engineered mice. 相似文献
24.
We examined the effects of early rearing experience on the development of dominance status in 53 juvenile (age 3) and then in 38 adult (ages 5-8) rhesus macaques. Based on previous research investigating the behavioral outcomes of nursery-rearing, we predicted that mother-reared (MR) monkeys would outrank peer-only reared (PR) monkeys, which would in turn outrank surrogate/peer-reared (SPR) subjects. Juvenile MR and PR subjects did not differ in ranks, but monkeys from both rearing backgrounds outranked SPR cage-mates at age 3. Independent of rearing condition, high-ranking juveniles gained the most weight between ages 1-3, suggesting that low status may be associated with decreases in early weight gain. Adult MR subjects outranked both PR and SPR subjects, with PR animals occupying intermediate ranks. These results indicate that impoverished early experiences, such as adult absence and limited social interaction, are useful predictors of future social success in rhesus macaques. 相似文献
25.
Point mutation of the BRAF gene is a common genetic event in papillary thyroid carcinomas. More recently, it has been found that BRAF can also participate in chromosomal rearrangement. In this study, we explore yet another possible mechanism of BRAF alteration, which involves copy number gain. Using fluorescence in situ hybridization with BRAF specific and chromosome 7 centromeric probes, we studied 62 follicular thyroid tumors and 32 papillary carcinomas. We found
that numerical changes in BRAF copy number were rare in papillary thyroid carcinomas, while they occurred in 16–45% of follicular tumors of conventional
and oncocytic (Hürthle cell) types. They were due to amplification of the gene or gain of one or more copies of chromosome
7. Tetrasomy for chromosome 7 was overall the most common finding. The changes in BRAF copy number did not overlap with RAS mutations in follicular tumors. In a group of follicular carcinomas, tumors with BRAF copy number gain were significantly more often widely invasive (67%) compared to tumors with no copy number change (18%).
By Western blotting, the tumors carrying four copies of the gene revealed higher expression of BRAF protein, suggesting that
copy number gain may represent another mechanism of BRAF activation in thyroid tumors. 相似文献
26.
A behavioral approach to increasing calorie consumption in children with cystic fibrosis 总被引:1,自引:1,他引:1
To increase calorie consumption of 5 mildly malnourished children with cystic fibrosis (CF), intervention was implemented in multiple baseline fashion across snack and three meals. Intervention involved nutritional education establishing gradually increasing calories goals, teaching parents contingency management strategies, and a reward system for achieving calorie goals. Following 6 treatment sessions, the children's calorie intake increased across meals and total calorie intake was 25 to 43% above baseline. The calorie increase was maintained at 9-month follow-up. Significant changes in weight and height were made during treatment and the year following intervention. The results suggest that the long-term oral intake of children with CF can be modified by a short-term behavioral intervention. 相似文献
27.
Disruption of diurnal feeding and weight gain cycles in weanling rats by ventromedial and dorsomedial hypothalamic lesions 总被引:1,自引:0,他引:1
L L Bernardis 《Physiology & behavior》1973,10(5):855-861
At the age of 28 days, male Sprague-Dawley rats received bilateral electrolytic lesions in the ventromedial (VMN) and dorsomedial (DMN) hypothalamic nuclei, repectively. Sham-operated rats served as controls. Food intake and body weight gains were measured for 13 days at the beginning of the light period (0800–2000 hr) and prior to the start of the dark period (2000-0800 hr). Both types of hypothalamic lesions caused a disruption of the naturally occurring diurnal feeding and weight gaining cycles. In accordance with previous data, the VMN rats remained normophagic and made normal weight gains while DMN animals were hypophagic and gained weight subnormally; linear growth was reduced in both types of lesioned animals, but only the VMN rats became obese. The data suggest the existence in the medial hypothalamus of an area that is involved in feeding and weight gaining cycles. From the standpoint of overall-caloric intake, this area consists of two types of neuronal assemblies that differ fuctionally as profoundly as they are anatomically separate. 相似文献
28.
The details of mechanical construction and electronic circuitry of a strain gauge system for continuously measuring food and water ingestion in laboratory rats are described. The system has been reliably tested over a number of years. It is eminently suitable for investigating daily rhythms in rat feeding and drinking behavior, where a large volume of data is collected over extended periods of time. 相似文献
29.
目的 探讨城市社区空巢老人社会支持与自理能力现状,并分析社会支持对空巢老人自理能力的影响。方法 采取多阶段分层随机抽样方法,抽取山东省城市社区卫生服务机构的2597名空巢老人作为研究对象,采用自编一般资料调查表、社会支持评定量表(SSRS)、日常生活活动能力量表(ADL)进行调查。结果 山东省社区空巢老人社会支持评分为低、中水平占97.2%,ADL受损者占74.1%;社会支持总评分(r=-0.137,P<0.01)及其主观支持(r=-0.150,P<0.01)、客观支持(r=-0.086,P<0.01)维度与日常生活活动能力呈负相关;回归结果显示,不同性别、年龄、婚姻状况、文化程度、患慢性病情况、两周患病情况、社会支持是ADL的影响因素,差异具有统计学意义(P<0.05)。结论 社区空巢老人自理能力较差,社会支持水平较低,社会支持与空巢老人自理能力呈负相关。通过“政府-社区-家庭”支持系统加强对空巢老人的社会支持,提升老年人自我照顾能力,提高其生活质量。 相似文献
30.
《Health & place》2022
The foodscape (the built food environment) is considered one of the driving factors of the higher burden of obesity and chronic disease observed in low socio-economic status (SES) groups. Traditional data collection methods struggle to accurately capture actual access and exposure to the foodscape (realised foodscape). We assess the use of anonymised mobile phone location data (location data) in foodscape studies by applying them to a case study in Perth, Western Australia to test the hypothesis that lower SES groups have poorer realised foodscapes than high SES groups. Kernel density estimation was used to calculate realised foodscapes of different SES groups and home foodscape typologies, which were compared to home foodscapes of the different groups. The location data enabled us to measure realised foodscapes of multiple groups over an extended period and at the city scale. Low SES groups had poor availability of food outlets, including unhealthy outlets, in their home and realised foodscapes and may be more susceptible to a poor home foodscape because of low mobility. 相似文献