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71.
B. L. McNaughton C. A. Barnes J. Meltzer R. J. Sutherland 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,76(3):485-496
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
72.
L. A. Basharova L. A. Vetrilé V. A. Evseev E. A. Gromova N. V. Bobkova L. A. Plakzhinas L. E. Fast 《Neuroscience and behavioral physiology》1990,20(2):109-113
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
73.
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
74.
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
75.
Rats were trained to run in a straight alley to escape shock. Subsequently, phenobarbital was administered and more trials given. Phenobarbital retards running at all doses tested in a curve that is positively accelerating as a function of dose on the first trial. The first trial is markedly slower than later trials with the greatest effect occurring at the higher dosages. 相似文献
76.
Rats were fed either a cereal-based or a purified casein-based diet in a foraging paradigm in which the costs of procurement and consumption were varied. The group offered the cereal-based diet consumed about 10% more calories than the group offered the casein-based diet, but both groups grew at the same rate. The intake of a control group offered a choice between the two diets was approximately 80% from the casein diet, and the growth of this group did not differ from that of the experimental groups. Variations in the cost of procurement and the cost of consumption affected the patterning of meals differentially for the two diets: changes in meal patterns tended to control the time and/or energy spent feeding. These results show that (1) meal patterns in the foraging paradigm are sensitive to subtle differences in diets, and (2) the amount of diet consumed (acceptance) and the choice between diets (preference) are determined by the economics of feeding and the nutritive quality of the foods, as well as by their palatability. 相似文献
77.
Radcliffe Jerilynn; Bennett David; Kazak Anne E.; Foley Bernadette; Phillips Peter C. 《Journal of pediatric psychology》1996,21(4):529-539
Examined the adjustment of 6- to 18-year-old children and adolescents(n = 38) 2 to 5 years postdiagnosis of brain tumor with respectto standardized measures of anxiety and depression; self-perceptions;and adaptive living skills. Child, mother, and teacher reportdata were used. Maternal adjustment (anxiety and depression,parenting stress) was also assessed. Children and adolescentssurviving brain tumors reported themselves to be generally withinthe normal range. However, maternal ratings of social problemswere higher than normative scores and significantly lower thannorms on social problems, scholastic competence, and communicationskills. Teacher ratings on the Teacher Rating Form were allwithin normal limits. Maternal adjustment measures were withinthe normal range, although the Parent-Child Dysfunctional Interactionsubscale of the Parenting Stress Index was elevated. No differencesin scores were found between children in regular and specialeducation, or between children who had received radiation andthose who did not. This sample of survivors of pediatric braintumors and their mothers had relatively mild problems in adjustment,supporting a competency-based view of the adaptation of pediatricpatients and their families. 相似文献
78.
Tohru Yashiro Motohiko Aiba Takao Obara Yoshihide Fujimoto Akira Hirayama 《Pathology international》1988,38(3):371-381
A case of primary plasmacytoma of the thyroid gland which occurred in a 63-year-old woman is reported. Histologic and ultramicroscopic examination revealed that the excised thyroid tumor was plasmacytoma superimposed on lymphocytic thyroiditis. Immunohistological study showed that the tumor cells produced intracytoplasmic immunoglobulin (IgG-kappa). Electropho-retic and immunoelectrophoretic studies disclosed the presence of monoclonal immunoglobulin (IgG-kappa) in samples of the patient's serum which had been obtained preoperatively. After completion of irradiation therapy to the neck following tumor removal, the serum monoclonal immunoglobulin disappeared. The patient is currently alive and well without any evidence of the tumor three years after surgery. 相似文献
79.
大学生性行为及性道德观发展研究 总被引:6,自引:0,他引:6
目的 了解当代大学生性行为及性道德观念的发展变化。方法 自制问卷,对全国9所高校的2000余名大学生进行调查,并用SPSS10.0对结果进行统计处理。结果 大学生性交行为发生率呈逐年上升趋势,且随年级上升而增加;大学生认可性交行为道德观的5个雏度,但各年级之间有差异;大学生边缘性行为和独自性行为发生率随年级显著上升,认可度也随年级增加而上升;大学生对同性性接触基本持排斥态度,但排斥态度则趋于下降。结论 大学生性行为和性道德随年级上升而明显变化,应加强学校教育和引导。 相似文献
80.
C57BL/6J (B6) and DBA/2J (D2) mice differ in maternal behavior and nest building, but previous observations on nest building appear to be contradictory. Lactating B6 females spent more time nest building than lactating D2 females [Physiol. Behav. 67 (1999) 599.]; however, pregnant D2 females have been reported to build better nests than pregnant B6 females [Physiol. Behav. 29 (1982) 153.]. To resolve this apparent discrepancy, virgin B6 and D2 females were mated, and the nest quality of nulligravid, primigravid and lactating primiparous females was compared between groups and with that of virgin females. There were no strain differences in the nest ratings of virgin or mated nulligravid females, nor did these groups differ within strains. Pregnant and lactating females of both strains built better nests than nonpregnant females. There was an increase in nest ratings in both strains on the day of parturition. The nest ratings of pregnant and lactating females were higher in B6 than D2 females. The largest strain differences were observed between pregnant B6 and D2 females. One hypothesis to account for these results is that females of these two strains differ in their levels of or sensitivity to hormones during pregnancy and parturition. 相似文献