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61.
A genome-wide scan was carried out on a segregating F2 population of rats derived from reciprocal intercrosses between two inbred strains of rats, Fisher 344 (F344) and Wistar Kyoto (WKY) that differ significantly in their behavioral coping responses to stress measured by the defensive burying (DB) test. The DB test measures differences in coping strategies by assaying an animals behavioral response to an immediate threat. We have previously identified three X-linked loci contributing to the phenotypic variance in behavioral coping. Here we report on six significant autosomal quantitative trait loci (QTL) related to different behaviors in the DB test:one for the number of shocks received, three for number of prod approaches, one for latency to bury, and one pleiotropic locus affecting both approach and latency. These QTL contributing to different aspects of coping behaviors show that the effect of genotype on phenotype is highly dependent on lineage. The WKY lineage was particularly influential, with five out of the six QTL affecting coping behavior only in rats of the WKY lineage, and one locus affecting only those in the F344 lineage. Thus, epigenetic factors, primarily of WKY origin, may significantly modulate the genetic contribution to variance in behavioral responses to stress in the DB test.  相似文献   
62.
Immune system responsiveness results from numerous factors, including endogenous cannabinoid signaling in immunocytes termed the "immunocannabinoid" system. This system can be an important signaling pathway for immune modulation. To assess the immunomodulating role of the cannabinoid 2 (CB2) receptor, we sought polymorphisms in the human gene, identified a common dinucleotide polymorphism, and investigated its effect on endocannabinoid-induced inhibition of T lymphocyte proliferation. The CB2 cDNA 188-189 GG/GG polymorphism predicts the substitution of glutamine at amino acid position 63 by arginine. T lymphocytes from CB2 188-189 GG/GG homozygotes had approximately twofold reduction of endocannabinoid-induced inhibition of proliferation compared with cells from CB2 188-189 AA/AA homozygotes. In GG/GG subjects, the reduced endocannabinoid inhibitory response was highly significant for N-arachidonylglycine and nearly significant for 2-arachidonylglycerol, and a specific CB2 receptor antagonist partially blocked these effects. Also, patients with autoimmune diseases had an increased prevalence of the homozygous GG/GG genotype. Collectively, these results demonstrate reduced endogenous fatty acid amide immunomodulatory responses in individuals with the CB2 188-189 GG/GG genotype and suggest that this CB2 gene variation may be a risk factor for autoimmunity. The results also support the proposition that the CB2 receptor may represent a novel pharmacological target for selective agonists designed to suppress autoreactive immune responses while avoiding CB1 receptor-mediated cannabinoid adverse effects.  相似文献   
63.
Summary A strain of avian influenza A virus, originally isolated from an epidemic among turkeys, was adapted to human cells by serial passages. Four passage levels of the virus were compared with respect to their growth potential in human cell monolayers and their plaque morphology in chick embryo fibroblasts and in HeLa cells. The original virus, never passed in human cells before, was already able to replicate in human cells. Serial passages in human epithelial cells increased this ability. Further serial passages in human myeloblasts resulted in the selection of an apparently stable mutant which grew well in human malignant epithelial cells and even better in diploid human fibroblasts.  相似文献   
64.
Summary The present report describes the results of a combined morphological, enzyme- and immunohistochemical analysis of nine cases of malignant non Hodgkin's lymphomas (NHL) clinically presenting as lethal midline granuloma. In a previous report written before antibodies directed against B and T lymphocytes were available, a histiocytic origin of such neoplasms had been suggested. A panel of antibodies reactive with most B cells (L26, MB1, KiB3) and a majority of T cells (MT1, UCHL1) was applied on paraffin sections of formalin fixed tissues as well as antibodies directed against leukocyte common antigen (LCA), myeloid/histiocyte antigen (MAC 387), lysozyme, alpha-1-antitrypsin, alpha-1-antichymotrypsin, S-100 protein, prekeratin and immunoglobulin light chains. Enzyme histochemistry included tests for non-specific acid esterase, acid phosphatase, betaglucuronidase and chloroacetate esterase. As a result, five T, two B and two unclassified (malignant histiocytosis probable) NHL were identified, indicating distinct heterogeneity of NHL as causative disorders in lethal midline granuloma.  相似文献   
65.
Three patterns of activity were evident when the differential activation of the DNA polymerase associated with serum Dane particles by nonionic detergent and salt was investigated. The patterns were obtained by plotting the increase in enzyme activity mediated by the detergent Nonidet P-40 (NP-40) in increasing concentrations of KCl compared to the activity observed in the absence of detergent. The pattern of differential activity of hepatitis B (HB) DNA polymerase in detergent and salt was altered by subjecting the HBAg preparations to shearing forces. Hepatitis B DNA polymerase activity was stable even in NP-40 concentrations as high as 10%. In addition to hepatitis B DNA polymerase, DNA polymerase activated by calf thymus DNA was found in pellets containing Dane particles. The latter DNA polymerase activity was also activated by NP-40 and was not decreased by DNAse; this DNA polymerase coprecipitated with hepatitis B antigen (HBAg) upon addition of anti-HBs. However, the DNA polymerase activated by calf thymus DNA was inhibited by 0.4 M KCl. Electron microscopic observations of serum Dane particles in 0.4 M KCl showed no alterations of morphology of these particles when compared to particles in low-salt buffer. The data indicated that KCl activated HB DNA polymerase by a different mechanism from that of shear or NP-40, which removed the surface antigen coat from the Dane particles.  相似文献   
66.
67.
In the present paper, two experimental models of heart failure, namely hereditary cardiomyopathy in hamsters (BIO 14.6) and cardiac insufficiency due to mild (0.06 microM) isoprenaline overload of rabbit isolated perfused hearts, were compared in terms of resulting alterations at the level of the functionally isolated contractile system of detergent/glycerol treated skinned cardiac fibres. As the main features of Ca activation of tension in these models, the following were found: 1. Within the same species (RB hamsters, BIO 14.6 hamsters or rabbits), the Ca sensitivity, measured as pCa for half maximal Ca activation, was invariably higher in left than in right ventricular skinned fibres. 2. During the development of hereditary cardiomyopathy (BIO 14.6), maximum Ca-activated tension, measured per unit cross-sectional area, was reduced in an age-dependent manner, without any significant reduction in Ca sensitivity. This effect appeared to be more pronounced in left than in right ventricles. 3. In skinned fibres from right or left ventricular papillary muscles from in vitro isoprenaline pretreated rabbit hearts, no significant alteration in the maximum Ca-activated tension (per unit area) was observed in comparison to non-pretreated control hearts, whereas the Ca sensitivity was reduced. Treatment of control or failing heart skinned fibres with cAMP showed no additivity to the Ca desensitization induced by isoprenaline pretreatment. 4. Skinned fibres from isoprenaline pretreated left ventricular rabbit hearts showed a higher susceptibility to the Ca sensitizing effect of APP 201-533 than fibres from unpretreated control hearts. Mild isoprenaline overload and hereditary cardiomyopathy both are forms of heart failure which are presumably not associated with a lack of activator Ca. It is concluded that cardiotonic agents increasing the cardiac myofibrillar sensitivity to Ca ions would be beneficial in both cases, representing a phenomenologically causative treatment in hearts failing due to isoprenaline pretreatment. A main advantage over "classical" cardiotonic agents like cardiac glycosides, beta adrenergic stimulants or phosphodiesterase inhibitors would be the absence of the risk of drug-induced Ca overload.  相似文献   
68.
In 60 adult patients undergoing general surgical procedures, the effect of pancuronium or d-tubocurarine "pretreatment" on the injection of a 0.1 mg X kg-1 bolus of atracurium was measured in two separate studies. In study 1, the patients received either 0.5 mg (approximately 0.007 mg X kg-1) or 1.0 mg (approximately 0.015 mg X kg-1) pancuronium, or placebo (saline) three minutes before the injection of atracurium 0.1 mg X kg-1. In study 2, the patients received 0.05 mg X kg-1 or 0.1 mg X kg-1 d-tubocurarine, or a placebo. The degree of neuromuscular blockade was assessed by evoked mechanogram (adductor pollicis muscle) using supramaximal train-of-four stimulation. Patients receiving pancuronium or d-tubocurarine pretreatment (equal to an ED5-ED15 dose) showed significantly greater inhibition of twitch (ED70-ED80) and train-of-four ratio compared with the placebo groups (ED35-ED40). Pretreatment with the larger dose of d-tubocurarine (0.1 mg X kg-1) was associated with significant neuromuscular blockade. It is concluded that pancuronium and d-tubocurarine pretreatments potentiate the clinical action of 0.1 mg X kg-1 atracurium in man by 35-100 per cent.  相似文献   
69.
The Journal of Behavioral Health Services & Research - Mental health has long been a challenge on college and university campuses. Though it has historically taken a back seat to physical...  相似文献   
70.
BackgroundChildren with intellectual and developmental disabilities (IDD) often experience increased barriers to engaging in physical activity (PA) which can stem from lack of gross motor function (GMF) development. Intervening on GMF at an early age can create better opportunities for children with IDD to engage in regular PA. In turn, increased PA can improve health outcomes and increase social skills.ObjectiveThe primary objective of this pilot study was to explore the effectiveness of a community-based GMF-focused PA intervention for improving overall motor skills and PA for children with IDD.MethodsAll study participants (n = 24) engaged in 10 weeks of programming for 1 h each week. A convenience sample was utilized.ResultsResults indicated no statistically significant changes pre to post for motor skill scores. However, a visual analysis of mean changes showed a consistent pattern of increased scores from pre to post on most skills. Additionally, we found that a change in participant locomotor skills significantly predicted change in Moderate to Vigorous Physical Activity (MVPA), F (1,11) = 5.16, Adj R2 = .26, p = .04.ConclusionsThese results suggest individualized attention on GMF may help to increase motor skills for children with IDD. This study adds to the small but growing amount of research examining the efficacy of community based adapted PA interventions. Further, study results should support continued exploration of effective approaches to address the motor delays experienced by children with IDD.  相似文献   
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