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1.
Laysa Toschi Martins Henrique Ravanhol Frigeri Caio Cesar Silva de Castro Marcelo Távora Mira 《Experimental dermatology》2020,29(6):535-538
The aetiology of vitiligo has not been fully elucidated, and several hypotheses have been investigated; among them, the most explored assumes an autoimmune basis for the disease. Supporting this hypothesis is the frequent co-occurrence of autoimmune diseases with vitiligo. In addition, various genetic loci associated with vitiligo harbour key immune response genes. Our general hypothesis is that autoimmunity-associated genes participate in the control of vitiligo susceptibility. To investigate this hypothesis, we tested for association between vitiligo and genes CYP27B1, REL, TNFAIP3 and IL2/IL21, all previously related to autoimmune diseases associated with vitiligo. The study was performed using two independent population samples: a family-based discovery set (211 trios) and a replication set (131 cases/119 controls). Statistically significant association with vitiligo was detected between markers of the REL and IL2 gene in the family-based sample. Both association signals were concentrated among patients displaying autoimmune comorbidity and non-segmental vitiligo. Evidence for validation was detected for IL2 marker. Our findings suggest REL and IL2 as new vitiligo susceptibility genes and reinforce the hypothesis of a shared genetic mechanism controlling vitiligo and other autoimmune diseases. 相似文献
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Jayme Augusto Bertelli Madgid Taleb Assia Saadi Jean-Claude Mira Monique Pecot-Dechavassine 《Microsurgery》1995,16(2):77-85
Despite the introduction of microsurgical techniques into clinical practice, the results of surgical procedures involving the brachial plexus and peripheral nerves are still far from spectacular. We therefore studied the rat brachial plexus and its terminal branches in 203 rats. Detailed anatomic and morphologic analyses of the biceps brachii and musculocutaneous nerve, finger flexors, flexor carpi radialis, and the median nerve were performed. Various sources of conventional and vascularized nerve grafts were explored. After musculocutaneous nerve section or median nerve section, there were no articular contractures or automutilations, which constitutes an advantage for these experimental models over the sciatic nerve model. The brachial plexus and its terminal branches provide a good experimental model which can be used to assess the development and normal control of muscle function, examine the mechanisms underlying functional recovery, and test the effects of treatments to enhance recovery. © 1995 Wiley-Liss, Inc. 相似文献
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Paul P. W. van Buul Iris M. Zandman Mira Grigorova Jan J. W. A. Boei Adayapalam T. Natarajan 《Chromosome research》1995,3(7):427-432
The efficiency of two methods of detection of translocations induced in mouse stem cell spermatogonia by X-ray doses of 2, 5 and 7 Gy was compared: classical multivalent analysis at diakinesis-metaphase I of meiosis and observation via fluorescencein situ hybridization analysis of mitotic or meiotic stages. Specific DNA libraries for chromosomes 1, 11 and 13 were used. The results obtained indicate that (a) chromosomes 1, 11 and 13 are more involved in multivalent formation than expected on the basis of DNA content and (b) if the mitotic FISH analysis data are corrected for the observed over-representation, the frequencies of induced translocations are similar to those recorded in the classical multivalent studies, suggesting equal scoring efficiencies in both systems. 相似文献
5.
Why is the age-standardized incidence of low-trauma fractures rising in many elderly populations? 总被引:4,自引:0,他引:4
Pekka Kannus Seppo Niemi Jari Parkkari Mika Palvanen Ari Heinonen Harri Siev?nen Teppo J?rvinen Karim Khan Markku J?rvinen 《Journal of bone and mineral research》2002,17(8):1363-1367
Low-trauma fractures of elderly people are a major public health burden worldwide, and as the number and mean age of older adults in the population continue to increase, the number of fractures is also likely to increase. Epidemiologically, however, an additional concern is that, for unknown reasons, the age-standardized incidence (average individual risk) of fracture has also risen in many populations during the recent decades. Possible reasons for this rise include a birth cohort effect, deterioration in the average bone strength by time, and increased average risk of (serious) falls. Literature provides evidence that the rise is not due to a birth cohort effect, whereas no study shows whether bone fragility has increased during this relatively short period of time. This osteoporosis hypothesis could, however, be tested if researchers would now repeat the population measurements of bone mass and density that were made in the late 1980s and the 1990s. If such studies proved that women's and men's age-standardized mean values of bone mass and density have declined over time, the osteoporosis hypothesis would receive scientific support. The third explanation is based on the hypothesis that the number and/or severity of falls has risen in elderly populations during the recent decades. Although no study has directly tested this hypothesis, a great deal of indirect epidemiologic evidence supports this contention. For example, the age-standardized incidence of fall-induced severe head injuries, bruises and contusions, and joint distortions and dislocations has increased among elderly people similarly to the low-trauma fractures. The fall hypothesis could also be tested in the coming years because the 1990s saw many research teams reporting age- and sex-specific incidences of falling for elderly populations, and the same could be done now to provide data comparing the current incidence rates of falls with the earlier ones. 相似文献
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The present study investigated relationships between global QOL perceptions and well-being dimensions. Especially our goal was to evaluate the impact of generally recognised four broad dimensions of QOL (physical, functional, social and emotional well-being) on global QOL perceptions, additionally person's satisfaction with life achievements and economical situation were measured as well as social demographic variables. The subjects were a representative sample of Finns (n = 4613, from 25 to 65 years) of the FINRISK-97 study. Correlation coefficients and models of hierarchical regression indicated that physical, functional and social well-being as well as sociodemographic factors and satisfaction with life achievements are important factors of global QOL perceptions both among males and females. However percentages of variances explained with these measures were only moderately high, ranging from 1 to 10%. After measures of emotional well-being were entered into the models of hierarchical analyses of regression, variances explained grew dramatically over 20%. The results of the study indicated that global QOL judgements are likely to be based on current emotional state. 相似文献
8.
Spontaneous abortions and congenital malformations among women exposed to tetrachloroethylene in dry cleaning. 总被引:2,自引:1,他引:1 下载免费PDF全文
P Kyyr?nen H Taskinen M L Lindbohm K Hemminki O P Heinonen 《Journal of epidemiology and community health》1989,43(4):346-351
STUDY OBJECTIVE: The aim of the study was to determine whether exposure to tetrachloroethylene during the first trimester of pregnancy has harmful effects on pregnancy outcome. DESIGN: The study used record linkage identification of cases and case-control comparison. SETTING: The study involved dry cleaner and laundry workers throughout Finland who had become pregnant during the study period. Controls were age matched but otherwise unselected women giving birth to normal babies in the study period. SUBJECTS: Cases were defined as women who had been treated for spontaneous abortion or had delivered a malformed child. Out of 5700 workers nearly half had been pregnant during the study period. One pregnancy only was randomly selected for study per worker, and the final study population was 247 women with spontaneous abortions and 33 with malformed infants. Three age matched controls were selected for each abortion case and five for each malformation case. MEASUREMENTS AND MAIN RESULTS: Three women out of four had worked in early pregnancy. Exposure information was collected from 1108 women by mailed questionnaires, with a 77% response, and was partly confirmed by biological monitoring data. Exposure to tetrachloroethylene was found to be significantly associated with spontaneous abortions (odds ratio 3.6, p less than 0.05). CONCLUSION: The findings, together with other available data, indicate that exposure of pregnant women to tetrachloroethylene needs to be minimised. 相似文献
9.
Simultaneous transcutaneous PO2 (PtcO2) recordings, done on a neonate having preductal coarctation of the aorta, showed markedly lower PtcO2 values in the lower abdominal quadrant (representing postductal blood) than in the subclavicular area (representing preductal blood). Two-sensor PtcO2 recordings are valuable in documenting pathologic ductal shunts commonly associated with disturbed transitional circulation or cardiac malformation in newborn infants. 相似文献
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