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191.
The development of civic responsibility is considered to be an important component of healthy adolescent development. However, the study of its development has been relatively neglected and few studies have attempted to ground understanding of its development in a theoretical framework. The present study operationalized civic responsibility as attitudes and behaviors relating to political and community issues that are beneficial to society and compared two theoretical causal models, the social development model (SDM) and a coping‐competency model for their predictive value. Gender differences were also assessed. A total of 500 subjects, drawn from a longitudinal study (the Australian Temperament Project), participated in the study, using questionnaire and interview data. Approximately 1 in 5 adolescents actively engaged in behaviors reflecting community civic responsibility and less than 1 in 10 actively participated in the political arena. However, positive levels of social awareness were evident. Hierarchical multiple regression analyses indicated that the SDM had the most predictive value for political and community civic responsibility. Peer encouragement and peer participation were the most significant predictors. Variables from the coping‐competency model played some role in the prediction of community, but not political, civic responsibility. Gender differences in community civic responsibility, but not political civic responsibility, were found. One in two adolescents indicated that they would participate in volunteer work or political activities if more opportunities existed. This suggests the need for greater availability of appropriate community‐oriented activities for adolescents. © 2004 Wiley Periodicals, Inc. J Comm Psychol 32: 229–255, 2004.  相似文献   
192.
PAF-acether (PAF) or 2-methoxy-PAF (2-MX) caused a dose-dependent paw edema showing a 1: 25 ratio between their inflammatory activities. 2-MX caused a thrombocytopenia, whereas PAF did not alter the number of these cells. Both phospholipids induced reductions in total leukocyte count. Rat antiplatelet serum produced platelet depletion by PAF-induced paw edema was unaffected. The edema of 2-MX was significantly reduced by antiplatelet serum, under conditions where normal serum was inactive against the edema induced by PAF or 2-MX. Histopathological analysis of PAF and 2-MX-induced edema showed, in the first case, a small infiltrate of neutrophils, some lymphocytes, and several mastocytes around the vessels and, in the second, a neutrophilic infiltrate. These results suggest that PAF and 2-MX may produce edema through different mechanisms and that 2-MX causes edema in part through platelet activation.  相似文献   
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194.
Arbitrarily primed PCR (AP-PCR) was used to genotype 26 clinical isolates of Clostridium difficile previously analyzed by immunoblotting (IB) and 20 isolates typed by restriction endonuclease analysis (REA) with HindIII. Two levels of differentiation were achieved with the AP-PCR approach by use of two different arbitrary primers. With the 19-mer arbitrary primer T-7 (first level of differentiation), a good correlation was found between IB and AP-PCR typing. Twenty isolates grouped into six IB types were separated into seven major AP-PCR types. These seven AP-PCR groups were further discriminated into 12 subtypes after genotyping with the arbitrary primer PG-05 (second level of differentiation). The remaining six isolates, all of different IB types, showed a unique and distinct DNA banding pattern with both of the arbitrary primers, T-7 and PG-05. Twenty isolates representing 20 REA types from 15 REA groups were resolved into 13 AP-PCR DNA profiles with the arbitrary primer T-7. A good correlation was found at this level of differentiation between the major REA groups, Y and M, and AP-PCR typing. While AP-PCR with this primer failed to differentiate isolates in REA groups J, G, R, and B, AP-PCR with PG-05 resolved these four isolates into four distinct AP-PCR types. In addition, one of three M strains and one of four Y strains displayed a slightly different DNA banding pattern by AP-PCR (with PG-05) from that of the other strains in the group. We conclude that AP-PCR is a rapid and sensitive method which not only complements other typing schemes but also may be a substitute and prove to be especially suited for immediate epidemiological tracking of nosocomial infections due to C. difficile.  相似文献   
195.
CD-1 mice inoculated intraperitoneally with Mycobacterium avium, M. bovis, M. microti or M. kansasii showed a persistent peritoneal granulocytosis (above 10(6) cells, i.e. more than 15% of total cells) throughout the 3 month period of infection studied. By contrast, in mice inoculated with the non-pathogenic M. aurum or with heat-killed M. avium the number of granulocytes decreased progressively after the first 15 days. No mycobacteria were found in granulocytes except in the first 2 days of infection. The mycobacteria-induced chronic granulocytosis was accompanied by phagocytosis of granulocytes by macrophages. Throughout the 3 months of infection, macrophages were found to contain intracellular lactoferrin. Macrophages with lactoferrin were also found in subcutaneous infection caused by M. marinum and in systemic infection caused by M. avium or M. kansasii. The in vitro activity of mouse peritoneal macrophages against M. avium and M. microti was increased after ingestion of granulocyte material by macrophages. These results lead us to propose that granulocytes participate in the host response to mycobacterial infections, not as phagocytes but rather through an indirect mechanism, as a source for the macrophages of molecules involved in antimicrobial mechanisms (e.g., lactoferrin and myeloperoxidase) lacking in the mature macrophage.  相似文献   
196.
197.
Association of Streptococcus bovis Bacteremia with Bowel Disease   总被引:4,自引:5,他引:4       下载免费PDF全文
We reviewed the medical records of 19 patients who had Streptococcus bovis bacteremia. Eight patients had diverticulosis, four had benign adenomatous colonic polyps, and three had adenocarcinomas of the gastrointestinal tract. Laboratory workers and clinicians should be aware of the association of S. bovis bacteremia and gastrointestinal disease.  相似文献   
198.
BACKGROUND: Risk factors for acute wheezing among children in subtropical areas are largely unknown. OBJECTIVE: To investigate the role of viral infections, allergen sensitization, and exposure to indoor allergens as risk factors for acute wheezing in children 0 to 12 years old. METHODS: One hundred thirty-two children 0 to 12 years of age who sought emergency department care for wheezing and 65 children with no history of wheezing were enrolled in this case-control study. Detection of respiratory syncytial virus antigen, rhinovirus and coronavirus RNA, adenovirus, influenza, and parainfluenza antigens was performed in nasal washes. Total IgE and specific IgE to mites, cockroach, cat, and dog were measured with the CAP system. Major allergens from mites, cockroach, cat, and dog were quantified in dust samples by ELISA. Univariate and multivariate analyses were performed by logistic regression. RESULTS: In children under 2 years of age, infection with respiratory viruses and family history of allergy were independently associated with wheezing (odds ratio, 15.5 and 4.2; P = .0001 and P = .008, respectively). Among children 2 to 12 years old, sensitization to inhalant allergens was the major risk factor for wheezing (odds ratio, 2.7; P = .03). High-level allergen exposure, exposure to tobacco smoke, and lack of breast-feeding showed no association with wheezing. CONCLUSIONS: Some risk factors for wheezing previously identified in temperate climates were present in a subtropical area, including respiratory syncytial virus infection in infants and allergy in children older than 2 years. Rhinovirus was not associated with wheezing and did not appear to be a trigger for asthma exacerbations.  相似文献   
199.
The influence of the DNA repair genePSO3 on photoactivated psoralen-induced meiotic recombination, gene conversion, reverse mutation, and on survival, was assayed in diploid strains ofSaccharomyces cerevisiae homozygous for the wild-type or thepso3-1 mutant allele. Sporulation was normal in thepso3-1 diploid. Wild-type and mutant strains had the same sensitivity to photoactivated monofunctional psoralen (3-CPs+UVA) in meiosis-uncommitted and meiosis-committed stages. The mutant showed higher sensitivity to photoactivated bifunctional psoralen (8-MOP+UVA) during all stages of the meiotic cycle. Mutation induction by 3-CPs+UVA or 8-MOP+UVA in meiosis-committed cells revealed no significant differences between wild-type and thepso3-1 mutant. The status of thePSO3 gene has no influence on the kinetics of induction of gene conversion and crossing-over after 3-CPs+UVA treatment in meiosis-committed cells: gene conversion was blocked while recombination was induced. After treatment with 8-MOP+UVA gene conversion was also blocked in both strains while crossing-over could only be observed in meiosis-committed wild-type cells.  相似文献   
200.
We report on a 4-year-old girl with Duchenne muscular dystrophy (DMD). One of her sisters had grossly elevated serum creatine-kinase and pyruvate-kinase levels, and one of her maternal great uncles was presumptively affected by DMD. Cytogenetic analysis showed a 45,X/46,XX/47,XXX chromosome constitution. The maternally inherited DMD gene is presumed to be present on the single X of the 45,X cell line.  相似文献   
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