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Forty-one multiplex families, from published sources and new data from the National Cancer Institute, segregating for Hodgkin's disease and HLA, have been studied. A reanalysis of these data strongly suggests a recessive mode of inheritance for susceptibility to Hodgkin's disease. The HLA haplotype sharing data between affected relatives demonstrate that approximately 60% of cases in multiplex families are due to an HLA-linked susceptibility gene, the remaining 40% being due to other familial factors. The data clearly support the hypothesis of etiological heterogeneity for Hodgkin's disease, with both HLA-linked and HLA-unlinked factors being responsible. Finally, there is an increased concordance of histological types between affected relatives, but this concordance seems independent of HLA sharing.  相似文献   
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Heated sugar/amino acid reaction mixtures, known to contain products that are clastogenic and/or mutagenic to cells in vitro, were evaluated for clastogenic activity in mouse bone marrow using the erythrocyte micronucleus assay. Heated (i.e. browned) fructose/lysine reaction mixtures were also evaluated in the Salmonella his-reversion assay and the Chinese hamster ovary (CHO) cell chromosomal aberration assay to confirm and extend previous in vitro observations. Significant mutagenicity of fructose/lysine mixtures was observed in Salmonella typhimurium strains TA100, TA2637, TA98 and TA102, with greater activity in mixtures heated at pH 10 than at pH 7. S-9 decreased the activity in strains TA100, TA2637 and TA98, but increased the activity in strain TA102. Both pH 7 and pH 10 reaction mixtures of the fructose/lysine browning reaction were highly clastogenic in CHO cells. Heated mixtures of fructose and lysine, and of glucose or ribose with lysine, histidine, tryptophan or cysteine, did not increase the frequency of micronucleated erythrocytes in mice when administered by the oral route. This indicates the absence of chromosomal aberrations in erythrocyte precursor cells, and indicates that the genotoxic components of the browned mixtures are not absorbed and distributed to bone marrow cells in amounts sufficient to induce micronuclei when given orally. Because sugar/amino acid browning reactions occur commonly in heated foods, it is important to evaluate further the in vivo genotoxicity of browning products in cell populations other than bone marrow.  相似文献   
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Children with pure depression or depression plus an anxiety-related disorder (n = 14) had a higher drug response rate (57%) and a lower placebo response rate (20%) when compared to children with depression plus a concomitant conduct or oppositional disorder (n = 17) (33% drug response rate and 67% placebo response rate). These findings could explain why studies of prepubertal-onset depression found no differences between drug and placebo treatment assuming that a large percentage of the studies' subjects had concomitant conduct or oppositional disorders. The children with pure depression or depression plus an anxiety-related disorder had different symptom clusters from those with depression plus a concomitant conduct or oppositional disorder. The former had more severe CDRS ratings on sleep, appetite disturbance, depressed feelings, and psychomotor retardation. In contrast, those with a concomitant conduct or oppositional disorder had shorter attention spans and were more likely to disturb other children (based on Conners scale scores).  相似文献   
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Conventional risk factors have very low predictive power in identifying haemodialysis patients at high risk of vascular accidents. A role for apolipoprotein E isotypes was looked for in a small, but rigorously defined, cohort of longterm haemodialysis patients. In individuals with high vascular risk, as identified by higher common carotid intima/media thickness, we found an excess of apolipoprotein E4 alleles. This preliminary result requires confirmation in large patient cohorts.   相似文献   
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Multiple vascular lesions in the brain were identified by angiography in a 45-year-old woman with Von Hippel Lindau disease. One of these lesions was a histologically-proven hemangioblastoma. The occurrence of such lesions in a cerebral hemisphere is exceedingly rare and is usually related to Von Hippel Lindau disease.  相似文献   
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