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21.
Willer CJ Dyment DA Risch NJ Sadovnick AD Ebers GC;Canadian Collaborative Study Group 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(22):12877-12882
Size and ascertainment constraints often limit twin studies to concordance comparisons between identical and fraternal twins. Here we report the final results of a longitudinal, population-based study of twins with multiple sclerosis (MS) in Canada. Bias was demonstrably minimized, and an estimated 75% of all Canadian MS twin pairs were ascertained, giving a sample sufficiently large (n = 370) to permit additional informative comparisons. Twinning was not found to affect prevalence, and twins with MS did not differ from nontwins for DR15 allele frequency nor for MS risk to their siblings. Probandwise concordance rates of 25.3% (SE +/- 4.4) for monozygotic (MZ), 5.4% (+/-2.8) for dizygotic (DZ), and 2.9% (+/-0.6) for their nontwin siblings were found. MZ twin concordance was in excess of DZ twin concordance. The excess concordance in MZ was derived primarily from like-sexed female pairs with a probandwise concordance rate of 34 of 100 (34 +/- 5.7%) compared with 3 of 79 (3.8 +/- 2.8%) for female DZ pairs. We did not demonstrate an MZ/DZ difference in males, although the sample size was small. We observed a 2-fold increase in risk to DZ twins over nontwin siblings of twins, but the difference was not significant. 相似文献
22.
Kees J.M. Lips Jaap Van Der Sluys Veer Albert Struyvenberg AD Alleman John R. Leo Paul Wittebol Werner H. Minder Cornelis J. Kooiker Rolf A. Geerdink Paul F.G.M. Van Waes Wil H.L. Hackeng 《The American journal of medicine》1981,70(5):1051-1060
Two kindreds with the multiple endocrine neoplasia type 2A syndrome were studied. Of one of these we examined 150 members, 20 of whom were treated with thyroidectomy for medullary carcinoma and nine with bilateral adrenalectomy for pheochromocytoma. Of the second kindred 59 members were examined, seven of whom were thyroidectomized and seven treated with bilateral adrenalectomy. Pheochromocytomas were invariably found on both sides, even in four cases in which the adrenals on one side appeared to be completely normal, not only at preoperative roentgenologic examination but also on inspection during the operation. The microscopic finding of micronodules and a cluster of abnormal medullary cells identical with those found in pheochromocytomas in one of the apparently normal adrenals represents a first stage in the development of diffuse medullary hyperplasia as well as nodular hyperplasia. This is in accordance with the fact that in the MEN type 2A syndrome pheochromocytomas are always multicentric and multiple in origin. On the basis of these findings we conclude that all patients with the MEN 2A syndrome who show symptoms and signs of active pheochromocytoma should be subjected to bilateral adrenalectomy, even when one or both of the adrenals appear to be normal at roentgenologic investigation. 相似文献
23.
Anal cancer is one of the most common non‐AIDS‐defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV‐infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV‐related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV‐infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV‐infected adults. 相似文献
24.
Gui-Xian Zhao Ying Liu Zhen-Xin Li Chuan-Zhen Lv Anthony Traboulsee A. Dessa Sadovnick Zhi-Ying Wu 《神经科学通报》2013,29(5):525-530
Multiple sclerosis(MS)and neuromyelitis optica(NMO)are common autoimmune demyelinating disorders of the central nervous system.The exact etiology of each remains unclear.CYP7A1was reported to be associated with NMO in Korean patients,but this is yet to be confirmed in other populations.In this study,we used Sanger sequencing to detect SNPs in the promoter region of CYP7A1 in a population consisting of unrelated patients and controls from the Han Chinese population(129 MS;89 NMO;325 controls).Two known SNPs,204A〉C(rs3808607)and 469T〉C(rs3824260),and a novel SNP(208G〉C)were identified in the 5'-UTR of CYP7A1.The 204A〉C was in complete linkage with 469T〉C and both were associated with NMO but not with MS.Results suggest that the CYP7A1 allele was associated with NMO.NMO and MS have different genetic risk factors.This further supports the emerging evidence that MS and NMO are distinct disorders. 相似文献
25.
26.
Recent studies have shown that antithrombin III (AT III)/heparin is capable of inhibiting the catalytic activity of factor VIIa bound either to relipidated tissue factor (TF) in suspension or to TF expressed on cell surfaces. We report studies of the mechanism of which by AT III inhibits factor VIIa bound to cell surface TF and compare this inhibitory mechanism with that of tissue factor pathway inhibitor (TFPI)-induced inhibition of factor VIIa/TF. AT III alone and AT III/heparin to a greater extent reduced factor VIIa bound to cell surface TF. Our data show that the decrease in the amount of factor VIIa associated with cell surface TF in the presence of AT III was the result of (1) accelerated dissociation of factor VIIa from cell surface TF after the binding of AT III to factor VIIa/TF complexes and (2) the inability of the resultant free factor VIIa-AT III complexes to bind effectively to a new cell surface TF site. Binding of TFPI/factor Xa to cell surface factor VIIa/TF complexes markedly decreased the dissociation of factor VIIa from the resultant quaternary complex of factor VIIa/TF/TFPI/factor Xa. Addition of high concentrations of factor VIIa could reverse the AT III-induced inhibition of cell surface factor VIIa/TF activity but not TFPI/factor Xa-induced inhibition of factor VIIa/TF activity. 相似文献
27.
Background
To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). 相似文献28.
We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs. 相似文献
29.
Sparks DL Connor DJ Browne P Sabbagh MN;AD Cholesterol-Lowering Treatment Trial Team 《Journal of molecular neuroscience : MN》2002,19(1-2):209-212
Elevated circulating cholesterol can have profound effects on the health of an individual. Such excess cholesterol can promote
coronary artery disease, production and accumulation of β-amyloid in the brain, and possibly Alzheimer’s disease (AD). In
a clinical trial evaluating the benefit of a cholesterol-lowering drug in the treatment of AD, mean cholesterol levels at
baseline among individuals participating in the trial were found to be relatively high. Based on this observation we suggest
that cholesterol levels should be actively monitored in the elderly, as many individuals with AD are over 65 years of age
and therefore excluded by currently accepted guidelines. 相似文献
30.
SE Daley AD Pearson AW Craft J Kernahan RA Wyllie L Price C Brock C Hetherington D Halliday K Bartlett 《Archives of disease in childhood》1996,75(4):273-281
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover. 相似文献