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71.
Nesting behavior was found to differ for animals of five different inbred strains ofMus musculus reared in the same environment, indicating heritable differences in level of nesting byMus. For two separate crosses, hybrid animals built larger nests than did animals of the inbred parental strains. In addition, from data of one of the crosses and derived generations, a very low heritability of nesting but substantial dominance variance were found. This pattern of results is expected of characters which have been the target of natural selection. MaleMus were found to build larger nests than females of all groups tested. These findings suggest that nesting byMus musculus represents required thermoregulatory behavior.This research was supported by NSF grant GU 2591 and HEW grant NS 09536.  相似文献   
72.
P L Fidel  Jr  M E Lynch    J D Sobel 《Infection and immunity》1994,62(3):1032-1038
It has been postulated that systemic cell-mediated immunity (CMI) is an important host defense factor against recurrent vaginal infections caused by Candida albicans. Using an estrogen-dependent murine model of vaginal candidiasis, we have previously shown that mice inoculated vaginally with C. albicans acquire a persistent vaginal infection and develop Candida-specific Th1-type systemic CMI. In the present study, experimental vaginitis was monitored in the presence of preinduced systemic Candida-specific CMI. Mice immunized systemically with C. albicans culture filtrate antigens (CaCF) in complete Freund's adjuvant (CFA) had Th1-type reactivity similar to that of vaginally infected mice. CaCF given to mice intravenously induced Candida-specific suppressor T (Ts) cells. Mice preimmunized with CaCF-CFA and given a vaginal inoculum of C. albicans had positive delayed-type hypersensitivity (DTH) reactivity from the time of vaginal inoculation through 4 weeks. Conversely, mice infected in the presence of Ts cells had significantly reduced DTH responses throughout the 4-week period in comparison with naive infected mice. However, the presence of Th1-type Candida-specific DTH cells or Ts cells, either induced in mice prior to vaginal inoculation or adoptively transferred at the time of inoculation, had no effect on the vaginal Candida burden through 4 weeks of infection. A similar lack of effects was obtained in animals with lower Candida population levels resulting from a reduction in or absence of exogenous estrogen. These results suggest that systemic Th1-type CMI demonstrable with CaCF is unrelated to protective events at the level of the vaginal mucosa.  相似文献   
73.
Interleukin (IL)-10 is a potent anti-inflammatory and immune-regulatory cytokine. Mice deficient in IL-10 production (IL-10(-/-)) develop a spontaneous inflammatory bowel disease, indicating that IL-10 is an important regulator of the mucosal immune response in vivo. To study the role of IL-10 in the host response to gastric Helicobacter infection, stomachs of IL-10(-/-) and wild-type mice were colonized with Helicobacter felis, as a model of human H. pylori infection. Within 4 weeks of H. felis infection, wild-type mice develop a mild, focal chronic gastritis. In contrast, H. felis-infected IL-10(-/-) mice develop a severe hyperplastic gastritis, characterized by a dense, predominantly mononuclear cell inflammation of the mucosa and submucosa and epithelial cell proliferation and dedifferentiation. Within 4 weeks of H. felis infection, there are striking alterations in the character of the gastric epithelium from IL-10(-/-) mice, including a profound loss of parietal and chief cells, focal de novo production of acidic mucins, and marked epithelial proliferation with disordered epithelial architecture. These findings indicate that, in the absence of IL-10, the inflammatory and immunological responses of the murine host to gastric colonization with Helicobacter is a rapidly evolving pathological process with features that mimic those associated with H. pylori infection in humans. H. felis-infected IL-10(-/-) mice may provide a model with which to investigate the cellular and molecular changes that stem from gastric infection with H. pylori.  相似文献   
74.
Skin testing and extrinsic allergic alveolitis   总被引:1,自引:0,他引:1       下载免费PDF全文
Skin testing with six common allergens, tuberculin and a sterile avian antigen preparation from pigeon serum was performed on 102 pigeon fanciers. The incidence of positive prick tests to common allergens was no different for subjects with extrinsic allergic alveolitis. EAA, caused by avian exposure than the whole group. Positive immediate weal and flare reactions following skin prick testing with avian antigen occurred in 22 subjects and was closely correlated with atopy. However, when the same antigen was administered intradermally, 69 subjects developed an immediate (15 min) weal and flare reaction which did not correlate with atopy, instead, the weal diameter correlated significantly with the serum IgG antibody titre against pigeon serum gamma-globulin antigen, and furthermore, the higher grades of reaction were highly selective for subjects with EAA. Ten subjects, all with strong early intradermal skin reactions, developed a late (4-6 h) skin reaction; this was again highly selective for EAA. The subjects with cutaneous anergy to tuberculin had markedly higher IgG antibody titres to avian antigens, and these included the majority of the subjects with alveolitis.  相似文献   
75.
P L Fidel  Jr  M E Lynch    J D Sobel 《Infection and immunity》1993,61(5):1990-1995
Women with recurrent vulvovaginal candidiasis often demonstrate a down-regulation of cell-mediated immunity (CMI) to Candida albicans detected by a lack of cutaneous delayed-type hypersensitivity (DTH) to Candida antigens. However, the role of systemic CMI as a host defense mechanism against recurrent vulvovaginal candidiasis is not well understood, in part because of the lack of a well-defined murine model of vaginal candidiasis. The present study was undertaken to determine: (i) whether soluble Candida culture filtrate antigens (CaCF) could be used to induce and detect Candida-specific CMI in mice and (ii) whether these antigens would be useful in detecting systemic CMI in mice given an experimental Candida vaginal infection. To this end, mice were immunized subcutaneously with CaCF in complete Freund's adjuvant, and within 7 days they developed Candida-specific DTH reactivity detected by footpad swelling (increase in footpad thickness, 0.36 mm) 24 h after footpad challenge with CaCF. Adoptive transfer studies showed that the DTH responsiveness was elicited by CD4+ DTH T cells. In mice given a vaginal inoculum of C. albicans blastoconidia (5 x 10(5)), footpad challenge with CaCF resulted in positive DTH responses (0.24 mm) as early as 1 week, responses similar to immunization in 2 to 3 weeks (0.33 mm), and sustained low levels of DTH reactivity (0.15 mm) through 10 weeks of vaginal infection. Vaginal lavage cultures revealed that peak vaginal Candida burden occurred 1 week post-vaginal inoculation (10(5) CFU) and declined 16-fold by week 10. These results provide evidence that Candida-specific systemic CMI is generated and can be detected longitudinally in mice with Candida vaginitis by a multiantigen preparation of Candida organisms which both initiates and detects Candida-specific CMI.  相似文献   
76.
Cells from three patients with early gonadal failure and a balanced reciprocal translocation involving the long arm of the X chromosome and an autosome were studied. Fibroblasts from a patient with a similar balanced reciprocal translocation but normal reproductive capabilities were also studied. Two of the four patients were found to have serologically detectable H-Y antigen on their cells. Since H-Y antigen has been found on the cells of other patients with X chromosome abnormalities but without a Y chromosome, it is thought that the X chromosome plays a role in the regulation of H-Y antigen expression. This study suggests that the long arm of the X chromosome may be involved but the location of a regulatory gene cannot be identified in these studies. These cases do not permit us to implicate H-Y antigen as a cause of gonadal dysgenesis and early gonadal failure in females who have structurally abnormal X chromosomes.  相似文献   
77.
We investigated whether a service-planning document outlining recommendations for what providers should address in treatment (i.e., targets) and the associated clinical techniques they should employ (i.e., practices) influenced the targets and practices that providers reported actually implementing during the subsequent treatment episode. Participants included 94 youths ages 4 to 17 (M = 13.57, SD = 3.59) who received community-based mental health services from the Hawai'i Child and Adolescent Mental Health Division. Data on targets and practices were compared across initial Mental Health Treatment Plans and Monthly Treatment and Progress Summaries. Data were analyzed using two-level, generalized mixed effects models with two-way cross-classification or linear mixed effects models. Providers were more likely to report the use of targets and practices in treatment if they were included within the treatment plan. In addition, the more closely targets addressed during treatment followed the recommended targets from the treatment plan, the more closely implemented practices followed the recommended practices listed in the treatment plan. Furthermore, as providers shifted their focus to different targets, a shift in their use of practices was also evident over time. Last, practices for which there is demonstrated efficacy for particular targets were more likely to be used. Service planning documents appear to help organize care; however, results also suggest possible limitations to the current system. These findings highlight potential areas for improvement in planning and care delivery.  相似文献   
78.
The radioallergosorbent test (RAST) for alternaria was compared to skin tests and bronchial challenges in children suffering from chronic intractable asthma. In contrast to when such children were tested with a timothy grass pollen extract, the bronchial challenge and skin test results against alternaria did not correlate significantly. When alternaria allergens were coupled to cyanogen bromide-activated microcrystalline cellulose, the RAST correlated with the results of skin testing but not bronchial challenge. It was demonstrated by column immunabsorption that some allergic sera contained sufficient IgG antibody against alternaria to competitively inhibit the RAST. When Sepharose 2B was substituted for cellulose as the insoluble support, the inhibition by IgG antibody was largely overcome and then the RAST correlated with both skin test and bronchial challenge results. Glycopeptides contribute significantly to the allergenicity of alternaria, and when these materials were coupled to a Sepharose 2B conjugate by mild oxidation, the RAST correlated with bronchial challenge, but not skin test, results. It was concluded that in this group of steroid-dependent asthmatic children, the correlation of the RAST with the in vivo challenges was strongly influenced by the presence of IgG antibody in the allergic sera and the chemical nature of the mould allergens investigated.  相似文献   
79.
The delivery of mental health services, particularly psychotherapy and other psychosocial care, is being increasingly limited by financial constraints. We briefly review three trends that will play an increasingly important role in the delivery of mental health services in large organizations such as health maintenance organizations. These are (a) an increasing role for self-help and bibliotherapy interventions, both in traditional and electronic formats; (b) mental health services being offered in settings other than mental health specialty clinics; and (c) an increased emphasis on mechanisms for improving the quality and type of services offered, including quality improvement methods and pay-for-performance.  相似文献   
80.
This study investigated the effects of 6 weeks' smoking cessation on serum levels of total-cholesterol, triglyceride, high-density lipoprotein cholesterol (HDL-C) and apolipoproteins A-I and A-II (apo A-I and apo A-II) in 64 subjects of both sexes. Smoking cessation was associated with an increase in levels of apo A-II. Concurrent changes in weight and alcohol consumption during attempted smoking cessation, together with change in thiocyanate level, were entered as predictor variables into a multiple regression analysis. The change in apo A-II was found to be best accounted for by change in plasma thiocyanate level, and, in women, change in HDL-C and apo A-I by change in weight. The changes induced by smoking cessation may be due, at least in part, to associated changes in alcohol consumption and/or dietary intake, but in the case of apo A-II there is evidence of a more direct effect.  相似文献   
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