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A sample enriched for familial combined hyperlipidemia (FCHL) was examined for evidence of an association between genotype at an apolipoprotein B (apoB) elevating locus defined by complex segregation analysis and FCHL. Complex segregation analysis detected a locus with a large effect on plasma apoB levels and was used to compute the most probable genotype of family members. None of the 35 normolipidemic adults carried a copy of the allele associated with elevated apoB levels, yet 58% of the 109 adults with FCHL carried 1 (29%) or 2 (28%) copies. Two of 28 (7%) normal children had 1 copy of this allele and none had 2 copies, while 88 of 182 (48%) children with FCHL had 1 (26%) or 2 (22%) copies. Further, 4l of 48 (85%) individuals classified as having hyperapobetalipoproteinemia did not carry a copy of this “elevated apoB” allele. Therefore, the presence of the allele associated with elevation of apoB level is highly predictive of FCHL and this association cannot be explained solely by the presence of elevated apoB levels in FCHL, suggesting that the locus controlling apoB levels may play an etiologic role in FCHL. © 1993 Wiley-Liss, Inc.  相似文献   
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The determination of penetration pathways of topically applied substances into the skin is the subject of several investigations. Recently, follicular penetration has become a major focus of interest. To date, a direct, non-invasive quantification of the amount of topically applied substance penetrated into the follicles had not been possible. The development of such a method was the aim of this study. Therefore, the advantages of both stripping techniques, tape stripping and cyanoacrylate skin surface biopsy, were combined and evaluated. Tape stripping was used to remove the part of the stratum corneum that contained the topically applied dye. Subsequently, the follicular contents were ripped off by cyanoacrylate skin surface biopsy. The combined method termed "differential stripping" was evaluated in vitro and in vivo , and the amount of topically applied fluorescent dye penetrated into the hair follicles was quantified after different penetration times. After 30 min, 5% of the recovered concentration of sodium fluorescein was found in the follicular infundibula, where it was still detectable after 48 h. Altogether, the results of this investigation revealed that differential stripping is a new method that can be used to study the penetration of topically applied substances into the follicular infundibula non-invasively and selectively.  相似文献   
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T-cell infiltration was detected by immunohistochemistry in only 2 of 10 sural nerve biopsies from patients with Guillain-Barré syndrome (GBS). The number of endoneurial macrophages, identified by the monoclonal antibody MAC 387, was increased, compared with the number in 10 cases of axonal neuropathy. Macrophage-associated demyelination was identified in 7 and axonal degeneration in 8 cases. Cytomegalovirus (CMV) genome was not detected with the polymerase chain reaction.  相似文献   
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The Toronto Sexual Contact Study comprises a cohort of 249 male sexual contacts of men with HIV disease which has been followed every 3 months for almost 5 years. On enrollment 143 were seropositive and 16 seroconverted during the follow-up period. By 31 December 1989, 41 of the 159 seropositive cohort members had developed AIDS. Using Cox relative risk regression models, we investigated the association of a number of laboratory and clinical variables and progression to AIDS. Fixed covariate models examined laboratory variables from the enrollment visit of cohort members, with time calculated from this date. In models assessing time dependent covariates, time was calculated from the estimated date of HIV infection. In the univariate models of either fixed or time dependent covariates, many variables were significantly associated with risk of progression to AIDS (T4 cell count, T4/T8 ratio, blastogenic responses to phytohemagglutinin, concanavalin A, and pokeweed mitogen, serum IgA, appearance of p24 antigen, and the development of oral hairy leukoplakia, thrush, or herpes zoster). Appearance of persistent generalized lymphadenopathy was not associated with increased risk of progression. In the multivariate model which evaluated fixed laboratory covariates, T4/T8 ratio, IgA level, and PHA response at enrollment were significantly associated with elevated risk.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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BACKGROUND: The purpose of this study was to describe the health status and work limitations in injured workers with musculoskeletal disorders at 1 month post-injury, stratified by return-to-work status, and to document their return-to-work trajectories 6 months post-injury. METHODS: A sample of 632 workers with a back or upper extremity musculoskeletal disorder, who filed a Workplace Safety and Insurance Board lost-time claim injury, participated in this prospective study. Participants were assessed at baseline (1 month post-injury) and at 6 months follow-up. RESULTS: One month post-injury, poor physical health, high levels of depressive symptoms and high work limitations are prevalent in workers, including in those with a sustained first return to work. Workers with a sustained first return to work report a better health status and fewer work limitations than those who experienced a recurrence of work absence or who never returned to work. Six months post-injury, the rate of recurrence of work absence in the trajectories of injured workers who have made at least one return to work attempt is high (38%), including the rate for workers with an initial sustained first return to work (27%). CONCLUSIONS: There are return-to-work status specific health outcomes in injured workers. A sustained first return to work is not equivalent to a complete recovery from musculoskeletal disorders.  相似文献   
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Epirubicin was studied in a phase I setting to find the maximum tolerated dose when given weekly for 3 of 4 weeks. Forty-one evaluable patients were treated in groups at doses increasing from 20 to 45 mg/m2. The highest dose level produced the maximum degree of myelosuppression (lowest neutrophil count, 1.9 X 10(9)/L; range, 0-3.7) recorded on Day 22. This was well-tolerated in this group of mainly pretreated patients. Nonhematologic side effects were minimal. This dose schedule allows a greater dose per unit time to be administered than other recommended schedules for epirubicin.  相似文献   
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