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C3H and C57Bl10 mice exhibit a differential susceptibility to arthritis induced by Mycoplasma pulmonis. Resistant C57Bl10 mice consistently demonstrated higher complement-fixing antibody titres than susceptible C3H mice throughout the development of the acute arthritis. A strong correlation was demonstrated between the levels of anti-mycoplasma antibody and resistance to acute arthritis in six strains of mice. To test the hypothesis that the difference of arthritis resistance of C3H and C57Bl10 mice was caused by a different susceptibility of their lymphocytes to mitogenic stimulation by M. pulmonis, we investigated the generation of non-specific immunoglobulin in vivo and in vitro. M. pulmonis acted as a polyclonal mitogen, but stimulated approximately equal responses in lymphocytes of both strains.  相似文献   
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Familial endometriosis   总被引:11,自引:0,他引:11  
Purpose The study aimed to identify families with endometriosis and to document disease seventy within the families and the clinical characteristics of the affected women.Results Two hundred and thirty women with surgically confirmed endometriosis in 100 families were identified. The families consisted of 19 mother-daughter pairs, 1 set of cousins and 56 sister pairs. There were 5 families with 3 affected sisters, 1 family with 5 affected sisters, and 18 families with 3 affected members in more than one generation. The mean age at the onset of symptoms and the mean age at surgical diagnosis was 22.1±8.8 SD (range 10–46) and 31.8±7.9 SD (range 15–56) years respectively. Seventy-nine women (34.3%) had revised AFS Stage I–II disease, and 151 (65.7%) had revised AFS Stage III–IV disease.Conclusion The study confirms a familial tendency for endometriosis and supports the hypothesis that endometriosis has a genetic basis.Presented at the 50th Annual Meeting of the American Fertility Society, San Antonio, Texas, November 5–10, 1994.  相似文献   
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Family size, infections, and asthma prevalence in New Zealand children.   总被引:8,自引:0,他引:8  
We conducted a prevalence case-control study to investigate the relation between family composition, infection, and development of asthma at age 7-9 years. Potential cases (399) and controls (398) were selected from the Wellington, NZ, arm of the International Study of Asthma and Allergies in Childhood, a population-based prevalence study. Further screening questions restricted cases to children with a diagnosis of asthma and current medication use (N = 233) and restricted controls to children without a history of wheezing and no diagnosis of asthma (N = 241). After controlling for confounders (including infections, atopy, and socioeconomic status), family size was strongly related to asthma. Having no siblings [prevalence odds ratio (POR) = 2.51; 95% confidence interval (CI) = 1.05-6.01] or one sibling (POR = 1.86; 95% CI = 1.14-3.03) was associated with an increased risk of asthma compared with having more than one sibling. Parent-reported rubeola infection (and possibly other similar viral exanthems) was independently associated with a decreased risk of asthma (POR = 0.48; 95% CI = 0.27-0.83), but reported pertussis infection (POR = 1.57; 95% CI = 0.58-4.24) and day care attendance in the first year of life (POR = 1.81; 95% CI = 0.93-3.51) were not strongly associated with increased risks of asthma.  相似文献   
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The purposes of this study were (a) to compare wheat antigen content of inhalable bakery dust in Canada and the Netherlands and, (b) to evaluate the validity of dust exposure measurement as a surrogate of specific antigen exposure. Wheat antigen exposure data from the studies of Canadian and Dutch bakeries were used to explore the correlation between dust and antigen levels, and identify factors explaining variability of the antigen content of bakery dust. Direct comparison and pooling of the data were possible because the same antigen assay was used in both studies. Wheat antigen exposure samples totaling 544 were available, all originating from personal full-shift monitoring of bakery workers. The wheat antigen content of bakery dust varied greatly between the two studies and with different products within each study. Bakery dust from the Canadian study had a much higher wheat antigen content. Therefore, the interstudy difference in the wheat antigen content of bakery dust was by far the most significant in undermining the validity of the use of dust levels as a surrogate measures of wheat antigen exposure. The production of croissants, wheat bread and buns, puff pastry, bagels, and cinnamon buns was associated with increased wheat antigen content of bakery dust, while in rye bread production, bakery dust with less wheat antigen content was emitted. Although we can, in part, account for the pattern of variability in the wheat antigen content of bakery dust (explaining 49% of it), we concluded that the effort involved in modeling it accurately would probably exceed that expended in direct measurement of the antigen level. Therefore, for the exposure assessments carried out for the purpose of managing occupational risks of aeroallergen exposure in bakeries, we recommend the use of analytical techniques that can directly measure antigen exposure.  相似文献   
110.
A two-stage sample survey was used to estimate the size of Texas' professional public health workforce and to describe its composition in terms of employment settings, job characteristics, and individual characteristics. The estimated 17,700 public health professionals employed in 1995 represented approximately three percent of the state's total health workforce. About 55 percent of all these professionals worked in agencies that provide population-based public health services. An estimated seven percent had formal public health education. These findings raise issues concerning the numerical adequacy of the state's supply of public health professionals, the adequacy of their educational preparation, and the human resources capacity of the state's official public health agencies.  相似文献   
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