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41.
2 mg/kg melanotan II (MTII, administered i.p.), a cyclic peptide analog of α-melanocyte stimulating hormone, at a single dose increased grooming in naive rats placed in an unfamiliar open-field device without changing locomotion or rearing. Male rats exposed to restraint/immobilization stress (IS) for 1 h on three consecutive days displayed increased grooming after the second stressor exposure, compared to pre-stress levels. MTII, administered to the rats after IS, enhanced the grooming response compared both to the pre- and post-stress values. The increase was greatest after the first dose and declined over the following two applications. As to the locomotion of rats in the entire experimental space, IS reduced the distance moved only after the first two stressor exposures; MTII did not influence these alterations. Locomotion in the central part of arena was not reduced by the stressor or by MTII, on the contrary, there was an increase in both groups after the third intervention. The only observed change in rearing was an increase in the MTII group after the third restraint exposure. Thus, MTII selectively increased grooming without markedly affecting the spatio-temporal structure of locomotor behavior in the open-field. The decline of MTII enhanced grooming over the three test days may be interpreted in terms of adaptation to the stressor and of the developing tolerance to the peptide.  相似文献   
42.
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   
43.
44.
The review by Cook and Blacher (2007 ) suggests that behavior therapy for tic disorders is indeed efficacious. Given the empirical support for these treatments, researchers should begin to place effort on examining various strategies for treatment dissemination. The current article addresses possible barriers to dissemination, focusing specifically on various concerns that have been raised by many medical and psychological care providers. The validity of these concerns is examined in the context of existing data. In addition, limitations of the current literature and future directions for research are discussed.  相似文献   
45.
平行平板流动腔的合理设计和使用   总被引:7,自引:2,他引:7  
高度远小于横向和纵向几何尺寸的平行平板流动腔,是当前用以体外研究细胞力学行为,特别是细胞粘附特性的主要工具之一。本文从目前常用的平行平板流动腔内流体定常流动时的切应力表达式出发,指出该切应力表达式仅适用于小雷诺数条件,由此确定平行平板流动腔几何尺寸的合理选择;通过对小孔入流和出流的平行平板流动腔流场的分析,指出该切应力表达式只在远离孔口边界一定距离,即达到均匀流动后成立。  相似文献   
46.
The question of the roles of the two main parts of the insect brain, the mushroom bodies and the central complex, in controlling motor coordination and triggering a variety of behavioral programs, including sound production, remains controversial. With the aim of improving our understanding of this question, we studied the parameters of songs used by five-day-old males during courtship for fertilized wild-type females (Canton-S, C-S) over 5-min periods at 25°C; males were of two wild-type Drosophila Melanogaster lines (Berlin and C-S). Berlin males lacking mushroom bodies because of treatment with hydroxyurea during development (chemical removal of the mushroom bodies) were used, along with two mutants with defects in the mushroom bodies (mbm 1 and mud 1), two mutants with defects in the central complex (ccb KS127 and cex KS181), and mutant cxb N71 with defects in both the mushroom bodies and the central complex. The experiments reported here showed that courtship songs in males lacking mushroom bodies were virtually identical to those of wild-type males. The main parameters of pulsatile song in mutants mbm 1 and mud 1 (interpulse interval and train duration) were insignificantly different from those of the songs of wild-type flies, though the stability of the pulse oscillator was the same. Flies of these lines were no different from wild-type flies in terms of courtship success (percentage of copulating pairs in 10-min tests). Conversely, the songs of mutants with defects in the central complex differed from those of wild-type males. Firstly, there was degradation of the stability of the pulse oscillator and interpulse intervals were very variable. In addition, pulses were often significantly longer and appeared multicyclic, as in the well-known cacophony mutant, while the mean train duration was significantly shorter. Males of the line cex KS181 usually courted very intensely, though abnormal sounds were generally emitted. Mutants cex KS181 and ccb KS127 were significantly less successful in courtship than wild-type flies. These data show that the central complex appears to play a very important role in controlling song, while the mushroom bodies are not related to this function.  相似文献   
47.
Summary The effects of massive destruction of granule cells of the fascia dentata on the spatial and temporal firing characteristics of pyramidal cells in the CA1 and CA3 subfields of the hippocampus were examined in freely moving rats. Microinjections of the neurotoxin colchicine were made at a number of levels along the septo-temporal axis of the dentate gyri of both hemispheres, resulting in destruction of over 75% of the granule cells. By contrast there was relatively little damage to the pyramidal cell fields. As assessed by three different behavioral tests, the colchicine treatment resulted in severe spatial learning deficits. Single units were recorded from the CA1 and CA3 subfields using the stereotrode recording method while the animals performed a forced choice behavioral task on the radial 8-arm maze. Considering the extent of damage to the dentate gyrus, which has hitherto been considered to be the main source of afferent information to the CA fields, there was remarkably little effect on the spatial selectivity of place cell discharge on the maze, as compared to recordings from control animals. There was, however, a change in the temporal firing characteristics of these cells, which was manifested primarily as an increase in the likelihood of burst discharge. The main conclusion derived from these findings is that most of the spatial information exhibited by hippocampal pyramidal cells is likely to be transmitted from the cortex by routes other than the traditional trisynaptic circuit. These routes may include the direct projections from entorhinal layers II and III to CA3 and CA1, respectively.  相似文献   
48.
The influence of induction of antibodies to the neuromediator serotonin in the case of active immunization of animals with a conjugate serotonin-protein antigen on the distribution of biogenic amines in the brain and on behavioral responses was investigated in experiments on rats. It was shown that active immunization of rats with a serotonin-protein conjugate leads to a decrease in serotonin, its metabolite 5-hydroxyindole-3-acetic acid, as well as dopamine in certain brain structures. Against a background of induction of antibodies to serotonin, the horizontal motor activity of the animals is decreased.Translated from Fiziologicheskii Zhurnal SSSR imeni I. M. Sechenova, Vol. 74, No. 10, pp. 1367–1372, October, 1988.  相似文献   
49.
A series of experiments examined the behavioral and pituitary-adrenal response to novelty of perinatally malnourished rats tested as adults after nutritional rehabilitation begun at weaning. Neither the behavioral measures of ambulation, rearing and defecation, nor the plasma corticosterone response to a brief exposure to an open field differentiated the previously malnourished subjects from controls. Similar to controls, previously malnourished subjects were also capable of displaying a graded corticoid elevation to environments increasingly different from the home cage. However, exploratory behavior, as measured by head-dip frequency and duration in the hole-board, was reduced in the previously malnourished rats. Although latency and amount of fluid consumed in a novel environment did not differ, previously malnourished rats were unable to use the cues associated with a consummatory behavior to modulate the pituitary-adrenal response to novelty. Thus, perinatal malnutrition does not influence either the behavioral or physiological activational response to novel stimulation but appears to alter the ability of the animal to use a consummatory behavior to modulate this response.  相似文献   
50.
OBJECTIVE: To examine, using direct observation methodology, differences in family functioning at mealtime between families of school-age children with cystic fibrosis (CF) and families of school-age children without a chronic illness. METHOD: Family functioning was rated using the McMaster Mealtime Interaction Coding System (MICS) during a videotaped dinner among 28 families of children with CF and 27 families of non-ill, age-matched peers. Families were rated on overall family functioning and on six dimensions of the MICS: task accomplishment, communication, affect management, interpersonal involvement, behavior control, and role allocation. RESULTS: Ratings for families of a child with CF were significantly lower than they were for comparison families on overall family functioning and on four of the six MICS dimensions: communication, affect management, interpersonal involvement, and behavioral control. Moreover, a significantly greater percentage of families of children with CF were rated in the unhealthy range on overall family functioning and on five of six MICS dimensions. There was no relationship between family functioning and child weight status for children with CF. CONCLUSIONS: The current study suggests that for families of school-age children with CF, the family system is negatively affected during mealtime. Dietary interventions need to address family-centered, as well as child-centered, interventions to help families manage challenges presented during the family meal.  相似文献   
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