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21.
The “strong Black woman” construct has been well-documented in the United States as both an aspirational icon and a constricting burden for African-heritage women. It has not been examined among African-Canadians. Drawing on qualitative interviews and standardized measures with 50 African-heritage women in Eastern Canada, our analysis reveals their perceptions of the construct as both strongly endorsed as a source of cultural pride, yet also acknowledged to take a terrible toll on health and well-being. The construct arises from and directly benefits racism. It is imperative that health professionals understand the ways it shapes health and help-seeking behaviors.  相似文献   
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ObjectivesThe role of pro-inflammatory cytokines in the course of chronic otitis media with effusion (COME) has been documented. However, there are fewer studies on the action of anti-inflammatory cytokines in the middle ear. We sought determine whether there is an association between COME and anti-inflammatory cytokines and whether there are any differences in the cytokine profile in COME children with and without atopy.MethodsEighty-four children were divided into 3 groups: 32 nonatopic children with COME (group NA), 31 atopic children with COME (group A), and 21 children without COME and without atopy (control group C). Specimens from the middle ear were collected and evaluated by enzyme-linked immunosorbent assay for the cytokines interleukin-1 receptor antagonist (IL-1Ra) and immunoregulatory IL-10.ResultsSignificantly higher IL-10 concentrations were found in both nonatopic and atopic children with COME compared to controls. No significant differences in IL-1Ra levels were found between atopic and nonatopic children with COME and the control group.ConclusionWe found no differences in the levels of IL-1Ra in atopic and nonatopic children with COME compared to controls. However, we found elevated IL-10 levels in the middle ear effusions from children with COME, with or without atopy. These elevated immunoregulatory cytokine levels suggest a role for new immunomodulatory treatments to prevent disease progression in COME, regardless of atopy.  相似文献   
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The effects of dietary lipid level, degree of saturation, and antioxidant supplements on ultraviolet‐light (UV) carcinogenesis were studied in female albino hairless mice. Twelve groups, of 42 animals each received a restricted, semipurified, isocaloric diet containing 4%, 12%, or 12% (60% hydrogenated) corn oil with or without antioxidants (2%, w/w). A regimen of escalating UV irradiation was employed until a cumulative dose of 142 J/cm2 had been delivered. Tumor development time in 50% of the population (TDT50) was derived from a cumulative distribution of time to tumor formation, which was estimated for all groups. Although there were no significant differences in TDT50s between animals receiving low and high unsaturated lipid dietary regimens, animals receiving hydrogenated corn oil demonstrated a significantly (p <0.01) greater TDT50 and fewer tumors per animal than those receiving either level of unsaturated corn oil. Antioxidants had no effect on TDT50s within any of the dietary groups. However, greater tumor multiplicity was observed in groups receiving unsaturated lipid and antioxidants.

These data demonstrate that the degree of dietary lipid saturation modifies the carcinogenic response to UV and suggest that dietary lipid may modify the previously reported inhibitory effect of antioxidants on UV carcinogenesis. It may be concluded that adherence to dietary standards is as important as other experimental parameters when comparisons of UV effects are involved.  相似文献   
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BackgroundOligonucleotides belong to a class of macromolecules with great potential for research and various therapeutic applications. Their mechanisms of action are extremely diverse, although they are rather homogeneous in composition. Single-stranded oligodeoxynucleotides are not only inhibitors of gene expression, but their CpG sequence motifs may activate the innate immune response. Recent progress made in preclinical and clinical testing, as well as the case of the most recently discovered RNA interference technology, will help to overcome efficacy problems of the previous approaches of the ‘standard therapy’ of such diseases as tumors and various infections.MethodsThe aim of this article is to present various therapeutic aspects of oligonucleotides, and to review the most significant therapeutic applications of synthetic oligonucleotides. This paper presents a comprehensive review of current literature on various therapeutic properties of synthetic oligonucleotides.ConclusionsThe available results gathered from preclinical and clinical studies suggest that TLR9-targeted therapy of oligonucleotides can stimulate both innate and adaptive immunity. It also appears that CpG ODNs are generally safe, although moderate adverse effects, based on a backbone-related mechanism have been reported. The presented studies demonstrate that adjuvant CpG ODN can unify an immune response that leads to enhanced antigen-specific Ab formation. CpG ODN may therefore provide a unique approach to enhancing the efficacy of immunization, including the strengthening of antitumor immunity.  相似文献   
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Sulfonylureas are used in treatment of diabetes. Resistance to these derivatives is a therapeutical problem. Sulfonylureas act through sulfonylurea receptor 1 (SUR1) in the beta cell. SUR1 also enhances a physiological secretion of insulin induced by an increase of glucose concentration. It may be expected that polymorphism of SUR1 gene can lead to beta cell dysfunction and resistance to sulfonylureas. The aim of this study was to examine the frequency of polymorphism in exon 22 of SUR1 gene and its correlation with type 2 diabetes mellitus and sulfonylurea treatment failure. The group consisted of 42 patients with type 2 diabetes. The controls were 46 persons with proper glucose tolerance. Polymorphism was found in 5 patients and in 1 control person. Neither statistically significant difference of polymorphism frequency nor correlation between polymorphism and sulfonylurea failure was found due to a low number of cases. Polymorphism of exon 22 of SUR1 gene appeared more frequent in diabetic than in non-diabetic subjects but this was statistically not significant.  相似文献   
29.
Arrhythmogenic right ventricular cardiomyopathy (ARVC) is an inheritant disease with an autosomal dominant mode of transmission with incomplete penetrance and variable expression. Linkage analysis in affected families succeeds in identifying 9 loci determining 9 subtypes of the disease. Genotype phenotype correlation is unclear and the influence of various environmental factors is discussed. OBJECTIVES: Genotype phenotype correlation in 2 pairs of monozygotic twins with ARVC and the role of environmental factors are analyzed. PATIENTS AND METHODS: Among 40 pts with ARVC and their 195 relatives there were 2 pairs of monozygotic twins: brothers, age 47 y; and sisters, age 48 y. History, ECG, Holter monitoring, 2D and Doppler Echo, and MRI were analyzed. RESULTS: Twin brothers: ARVC was diagnosed in the proband after the episode of VT with LBBB morphology (enlarged right ventricle, focal hypokinesia of apex, MR evidence of adipose tissue in RV wall). Identical morphology of RV was seen in asymptomatic twin brother. The patient presenting arrhythmia has been rowing for 4 years. Twin sisters: diagnosis was done during family screening. Both were asymptomatic. RV morphology typical for ARVC was found discrete in one of them (bulges adipose tissue in the RV apex); the latter showed changes suggesting RV abnormality (mild segmental dilatation of infundibulum, adipose tissue in a free wall of the RV). No differences in previous viral infections and sports involvement were observed. CONCLUSIONS: 1. Clinical picture of ARVC in monozygotic twins is not identical. 2. Strenuous effort may be a factor triggering the arrhythmia in pts with ARVC.  相似文献   
30.
Differentiation between asymptomatic sensitization to fungi and clinically relevant allergy is difficult. The aim of this study was to assess the value of nasal provocation with fungal allergens in the diagnosis of allergic rhinitis with special attention to the late phase of monitoring. Eighteen patients with allergic rhinitis and confirmed sensitivity to molds were included in the study. In 16 patients with allergic rhinitis, nasal provocation with fungal allergens was positive. The provocation tests were performed in the asymptomatic period. Stallergenes nasal provocation extracts were used. Extracts were blinded and patients were not informed whether allergen or control solution was tested. The results of both allergen and control solution challenge were compared. Results of the challenge were assessed with symptoms score (after 5 and 30 minutes and 6 and 24 hours), mast cell tryptase level (before and 30 minutes after), and cytological examination of the nasal fluid (before and 6 hours after), and an early and a late-phase of the allergic response was evaluated. Clinical reaction was noted in 16 patients, with significantly marked late phase of the allergic reaction in 14 subjects. The late phase was the only reaction to the challenge in 6 subjects. Tryptase level rose in 2 subjects, whereas significant increase in eosinophils count was observed in 11 patients (Wilcoxon test, p = 0.001). The nasal allergen challenge with fungal allergen seems to be a promising diagnostic method of allergic rhinitis. Late phase of the allergic reaction seems to be an important part of the assessment.  相似文献   
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