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41.
The association of sociodemographic and family composition data with obesity was studied in 1213 black and 1166 white girls, ages 9 and 10, enrolled in the National Heart, Lung, and Blood Institute''s Growth and Health Study. Obesity was defined as body mass index at or greater than age- and sex-specific 85th percentile as outlined in the Second National Health and Nutrition Examination Survey. The prevalence of obesity was higher for pubertal girls than for prepubertal girls and for girls with older mothers/female guardians. As odds ratio of 1.14 was observed for each 5-year increase in maternal age. Obesity was less common for girls with more siblings; the odds for obesity decreased by 14% for each additional sibling in the household. In blacks, the prevalence of obesity was not related to parental employment or to parental education. In whites, the odds of obesity were higher for girls with no employed parent/guardian in the household and for girls with parents or guardians with lower levels of educational attainment. Examining the associations between sociodemographic factors and risk of childhood obesity provides important clues for understanding racial differences in obesity, a major risk factor for coronary heart disease.  相似文献   
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A new class of drugs, the benzodiazepine inverse agonists, have recently been shown to antagonize some of the behavioral and sedative effects of benzodiazepines, barbiturates, and alcohol. Preliminary studies suggested that at least one of these drugs, RO 15-4513, may also be able to reverse the general anesthetic properties of volatile halogenated agents. Another inverse agonist, FG 7142, exhibits a similar ability to antagonize alcohol or benzodiazepines. However, FG 7142 is less potent than RO 15-4513 and has less affinity for the benzodiazepine receptor (BZR). The present studies were therefore undertaken to compare the analeptic effects and relative potencies of RO 15-4513 and FG 7142 on the anesthetic properties of pentobarbital compared with the general anesthetic agent halothane as measured by the time for recovery of the righting reflex in the rat. Three basic experimental paradigms were employed. Drug (FG or RO) or carrier was administered 5 minutes prior to the induction of pentobarbital anesthesia. Drug or carrier was administered to anesthetized animals 60 minutes after pentobarbital injection. Lastly, drug or carrier was administered 5 minutes prior to 15 minutes of halothane anesthesia. In addition, the selective benzodiazepine antagonist, flumazenil (RO 15-1788), was used to determine if the effects of the benzodiazepine inverse agonists on recovery from barbiturate or halothane anesthesia were due to activity at the BZR. The results revealed that RO was both more potent and more effective than FG at speeding recovery from barbiturate anesthesia in the rat. RO's effects appeared to be primarily due to BZR inverse agonist activity since it could be reversed by the BZR antagonist, flumazenil.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
43.
1. Bipolar affective patients are supersensitive to light. 2. Lithium treatment decreases retinal sensitivity to light. 3. Recent findings concerning lithium perturbation of the function of various members of the G proteins family including transducin (G1), as well as findings of lithium sensitive hyperactive G proteins in mononuclear leukocytes of patients with mania led to the hypothesis that lithium sensitive hyperfunctional G1 is responsible for the supersensitivity to light in affective patients. 4. Thus, a change in the usual route of lithium administration into eye drops delivery is hypothesized to be more efficient clinically, with the advantages of shortening the time delay necessary to achieve therapeutic effects, and having less systemic side effects and reduced toxicity.  相似文献   
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Apoptosis, the programmed death of cells, plays a distinct role in the etiopathogenesis of Multiple sclerosis (MS), a common disease of the central nervous system with complex genetic background. Yet, it is not clear whether the impact of apoptosis is due to altered apoptotic behaviour caused by variations of apoptosis-related genes. Instead, apoptosis in MS may also represent a secondary response to cellular stress during acute inflammation in the central nervous system. Here, we screened 202 apoptosis-related genes for association by genotyping 202 microsatellite markers in initially 160 MS patients and 160 controls, both divided in 4 sets of pooled DNA samples, respectively. When applying Bonferroni correction, no significant differences in allele frequencies were detected between MS patients and controls. Nevertheless, we chose 7 markers for retyping in individual DNA samples, thereby eliminating 6 markers from the list of candidates. The remaining candidate, the ERBB3 gene microsatellite, was genotyped in additional 245 MS patients and controls. No association of the ERBB3 marker with the disease was detected in these additional cohorts. In consequence, we did not find further evidence for apoptosis-related genes as predisposition factors in MS.  相似文献   
48.
Spike timing reliability of neuronal responses depends on the frequency content of the input. We investigate how intrinsic properties of cortical neurons affect spike timing reliability in response to rhythmic inputs of suprathreshold mean. Analyzing reliability of conductance-based cortical model neurons on the basis of a correlation measure, we show two aspects of how ionic conductances influence spike timing reliability. First, they set the preferred frequency for spike timing reliability, which in accordance with the resonance effect of spike timing reliability is well approximated by the firing rate of a neuron in response to the DC component in the input. We demonstrate that a slow potassium current can modulate the spike timing frequency preference over a broad range of frequencies. This result is confirmed experimentally by dynamic-clamp recordings from rat prefrontal cortical neurons in vitro. Second, we provide evidence that ionic conductances also influence spike timing beyond changes in preferred frequency. Cells with the same DC firing rate exhibit more reliable spike timing at the preferred frequency and its harmonics if the slow potassium current is larger and its kinetics are faster, whereas a larger persistent sodium current impairs reliability. We predict that potassium channels are an efficient target for neuromodulators that can tune spike timing reliability to a given rhythmic input.  相似文献   
49.
Apart from other lesions, 51 renal neoplasms were induced in rats by administration of methylethy-, dimethyl- and phenylmethylnitrosourea. 3 tumors originated from the renal pelvis and were classified as transitional cell papilloma (1) or transitional cell carcinoma (2). 48 neoplasms were considered as "mesenchymal tumors". These growths were regarded as rat kidney specific tumors. They display a wide spectrum of histological structures: spindle cells which are capable to differentiate into smooth muscle cells, fibroblasts, angioblasts, fat cells, and even into cartilage thus forming the typical microscopical features which are completed by the tendency of mesenchymal cells to swirl around preexisting renal tubules in several closely investing layers. As the cell of origin is not yet established the term "mesenchymal tumor" seems to be the most suitable one. There is no basis for classifying these tumor as nephroblastomas and the two entities should be strictly separated.  相似文献   
50.
BALB/c mice (6 to 8 weeks old) infected with Chlamydia trachomatis serovar L1 were sacrificed, and the yield of Chlamydia inclusion-forming units from the liver and lungs was measured in HeLa 229 cells. The yield of inclusion-forming units reached a peak at 3 days postinfection and then progressively declined. The mice infected with C. trachomatis had no detectable levels of gamma interferon (IFN-gamma) in their sera. However, stimulation of their spleen cells with either concanavalin A or heat-killed C. trachomatis resulted in the release of high levels of IFN-gamma (600 to 900 IU/ml) at 5 to 8 days postinfection. The increased release of IFN-gamma from the spleen cells paralleled the clearance of chlamydia from the liver and lungs. Sera and spleen cells from animals immunized with live C. trachomatis were transferred to recipient mice that were subsequently challenged with C. trachomatis. Transfer of spleen cells resulted in a reduction of the infection in the recipient animal as measured by the yield of chlamydia from the spleen, but transfer of the sera did not confer protective immunity. In addition, mice infected with C. trachomatis serovar L1 were treated with a hamster neutralizing monoclonal antibody to recombinant murine IFN-gamma (MAb-MuIFN-gamma). In the animals receiving the MAb-MuIFN-gamma, the yield of chlamydia from the lungs, spleen, and liver was significantly higher than from the control groups of mice. Histopathological analysis of tissues from the chlamydia-infected mice showed that the animals treated with the MAb-MuIFN-gamma had a significantly more extensive inflammatory reaction in their lungs, liver, and spleen.  相似文献   
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