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191.
As survival improves in β-thalassaemia, osteoporosis is emerging as a significant problem. This study examines bone mineral density (BMD) of thalassaemic patients of Asian origin (age range 9.5-24 y) to evaluate the extent of problems in this group and identify potential risk factors. Eleven patients were scanned using dual-energy X-ray absorptiometry. BMD z -scores and the bone mineral apparent density (BMAD) z -scores were calculated, to correct for short stature. All but three patients had lumbar spine BMD and BMAD z -scores below the mean. Three patients had BMAD z -scores more than 2.5 standard deviations below the mean. A negative correlation between age and BMAD was seen, as was an association between endocrine disorders and decreased bone density.

Conclusion: The data confirm significant reductions in BMD in the Asian thalassaemic population, even after correcting for body size. Further research is needed to identify risk factors and means of prevention.  相似文献   
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Regurgitation in infants is a common problem. Recent issues, such as the increased risk of sudden infant death in the prone sleeping position, the finding of persisting occult gastro-oesophageal reflux with feed thickeners, and the increasing awareness of the cost-benefit ratio of medications may challenge the currently recommended management approach. A round table was organized to elaborate on the impact of (i) the pro supine sleeping campaigns in relation to sudden infant death and (ii) advancement in medical treatment on therapeutic strategies in regurgitating infants. The participants were opinion leaders from Europe and North America (Belgium, Canada, France, UK, Italy, Switzerland and The Netherlands). The importance of parental reassurance is stressed. As a consequence of the supine sleeping campaigns aiming to decrease the incidence of sudden infant death syndrome, the "prone elevated sleeping position" is no longer advised as a first-line therapeutic approach, although it is still recommended in "complicated reflux". It is emphasized that milk thickeners are an adequate therapeutic tool for regurgitation, but not in reflux disease. According to the literature, the efficacy of (alginate-) antacids, although very popular in some countries, is questionable. These recommendations will be of interest to first-line paediatricians, since about 40% of their patients, according to the literature, present because of regurgitation.  相似文献   
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The common fragile site at 3p14.2 (FRA3B) is the most sensitive site on normal human chromosomes for the formation of gaps and breaks when DNA replication is perturbed by aphidicolin or folate stress. Although rare fragile sites are known to arise through the expansion of CCG repeats, the mechanism responsible for common fragile sites is unknown. Beyond being a basic component of chromosome structure, no biological effects of common fragile sites have been convincingly shown, although suggestions have been made that breakage and recombination at these sites may sometimes be mechanistically involved in deletions observed in many tumors and in constitutional deletions. In an observation related to the high rate of recombination at fragile sites, a number of studies have shown a statistical association between the integration of transforming DNA viruses and chromosomal fragile sites. Using FISH analysis we recently identified a 1.3 Mb YAC spanning both FRA3B and the t(3;8) translocation associated with hereditary RCC. Here we report the further localization of FRA3B within this YAC. Using lambda subclones of the YAC as FISH probes, gaps and breaks were found to occur over a broad region of at least 50 kb. Neither CCG nor CAG repeats were found in this region suggesting a different mechanism for fragility than seen with rare fragile sites. We further show that an area of frequent gaps and breaks within FRA3B, defined by a lambda contig, coincides with a previously characterized site of HPV16 integration in a primary cervical carcinoma. The HPV16 integration event gave rise to a short chromosomal deletion limited to the local FRA3B region within 3p14.2. Interestingly, 3p14.2 lies within the smallest commonly deleted region of 3p in cervical cancers, which are often HPV16 associated. To our knowledge this is the first molecular characterization of an in vivo viral integration event within a confirmed fragile site region, supporting previous cytogenetic observations linking viral integration sites and fragile sites.   相似文献   
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Why women resist screening mammography: patient-related barriers   总被引:16,自引:0,他引:16  
Mammography utilization remains below the level needed to achieve the National Cancer Institute's year-2000 goals for reducing breast cancer mortality by 50%. Previous research has identified both patient and physician barriers. The authors interviewed 600 randomly selected women who were offered a free mammographic examination. Interviews were conducted by professional interviewers using a brief, structured questionnaire. Data were analyzed with chi 2 Wilcoxon and Kruskal-Wallis rank-sum statistics and discriminant analysis. Noncompliant subjects reported more barriers than compliant subjects. The former were more likely to believe that mammography is unnecessary in the absence of symptoms and that it is inconvenient. In both the bivariate and multivariate analyses, the woman's belief that her doctor believes in regular mammography was an important predictor of compliance.  相似文献   
199.

Objective  

The impact of pain and depression on health-related quality of life (QoL) is widely investigated, yet the pain-depression interactions on QoL remain unclear. This study aims to examine the pain-depression-QoL mediation link.  相似文献   
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