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Purpose

The aim of this study was to determine risk for melanoma among individuals who have a first- or second-degree relative with a history of melanoma, based on the unaffected individual’s age and age at diagnosis of the relative.

Methods

The study employed a case–control design using a statewide database linked with a Surveillance Epidemiology and End Results cancer registry. A population-based sample of individuals who received at least one diagnosis of first primary, malignant melanoma (n?=?14,281), as well as their first- and second-degree relatives, was included. Control individuals with no history of melanoma (n?=?70,889) were matched to cases on birth year, gender, race/ethnicity, and county at birth.

Results

Risk for melanoma among relatives of melanoma patients declined with relative’s age and age at diagnosis. Individuals between ages 40 and 49 who are first-degree relatives of melanoma patients diagnosed between ages 40 and 49 had the greatest risk for melanoma compared with individuals without a first-degree relative with a melanoma history (HR 4.89; 95% CI 3.11–7.68). Increased melanoma risk among second-degree relatives of patients was typically lower than that for first-degree relatives.

Conclusions

Risk for melanoma, at earlier ages than expected, is increased among relatives of individuals with a history of melanoma, particularly if the melanoma case was diagnosed at a young age. Further research on the relationship between age at diagnosis and relative’s melanoma risk could inform melanoma screening recommendations for individuals with a family history of the disease.
  相似文献   
955.
The presentation of peptide antigens to T-cells by MHC Class II proteins is a central process in cellular and humoral immune responses. Blockade of this presentation event via synthetic ligands that bind to disease-associated MHCs (such as DR1 and DR4) may be useful for the treatment of autoimmune diseases such as rheumatoid arthritis, Type 1 diabetes, multiple sclerosis, lupus erthymatosis and Graves disease. Recently reported synthetic ligands for DR1 and DR4 are short modified peptides (2-7 mers) capable of competing at nanomolar concentrations with antigenic peptides for the DR (MHC) binding groove.  相似文献   
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Objectives: This study examined the association between participation in Medicaid managed care and up-to-date coverage for childhood immunizations and screenings among private practice physicians serving New York City's poorest neighborhoods. Method: A random sample of 2174 children 3–35 months of age was drawn from 60 physician practices in 1995, and a cross-sectional analysis was used to compare up-to-date status for immunizations, and lead and anemia screening tests, for children cared for by managed care and nonmanaged care physicians. In 1996, an independent sample of 2380 children from the same practices was used to compare up-to-date status for individual children enrolled in Medicaid managed care and children predominantly enrolled in traditional fee-for-service Medicaid. Information from physician interviews augmented chart review data. Chi-square analysis and logistic regression were used. Results: Physicians who participate in Medicaid managed care and those who do not had equal up-to-date coverage for immunizations (41.0 vs. 36.9%, p = .527), and lead (46.8 vs. 38.7%, p = .199) and anemia screening (63.2 vs. 56.5%, p = .272). Measures of the process of care were also similar for the two groups of physicians. Children themselves enrolled in Medicaid managed care appeared significantly more likely to be up-to-date than their nonmanaged care counterparts for immunizations (OR = 1.53, p = .027) and anemia screening (OR = 2.95, p = .000). Conclusions: Participation in managed care does not seem to change physicians' overall preventive care practice behavior. Available data did not reveal major differences in demographics or health status between individual children enrolled in managed care and those not enrolled. That children enrolled in managed care were better immunized and screened than those in fee-for-service Medicaid suggests that physicians receiving compensation under two payment systems may treat children differently depending on each child's mode of reimbursement.  相似文献   
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Summary The activity of dopamine--hydroxylase, the enzyme that catalyzes the conversion of dopamine to norepinephrine, was measured in the serum of a strain of Wistar rats homozygous and heterozygous for a genetic form of hypothalamic diabetes insipidus and in Wistar control rats. Serum dopamine--hydroxylase activity and water intake was highest in the homozygous affected rats and lowest in normal controls. Treatment with pitressin tannate reduced serum enzyme activity and water intake in rats with diabetes insipidus to levels which did not differ from controls. Thus serum dopamine--hydroxylase activity appeared to vary directly with changes in sympathetic nerve activity in response to intravascular volume depletion and repletion.  相似文献   
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Thirty-two Escherichia coli and 21 Klebsiella pneumoniae septicemia isolates with varying degrees of resistance to ciprofloxacin were analyzed for the presence of point mutations within the quinolone-resistance target genes. The number of mutations observed in the resistant isolates agreed with the level of ciprofloxacin resistance in both species. Such isolates were also resistant to nalidixic acid. Isolates with borderline susceptibility to ciprofloxacin, on the other hand, behaved differently in the two species. In E. coli all the isolates harbored at least one mutation and these isolates were also resistant to nalidixic acid, while no mutations were detected in the K. pneumoniae isolates, and susceptibility to nalidixic acid was unpredictable. Therefore, nalidixic acid cannot be used as a class representative. Time-kill curve studies on an isolate with borderline susceptibility from each species showed higher degrees of resistance to ciprofloxacin in comparison to that of the wild-type E. coli. A previously unreported parC mutation, S57-->T, was detected in a resistant E. coli isolate and might expand the QRDR of this gene. Normalized resistance interpretations of histograms confirmed the setting of microbiological zone breakpoints for ciprofloxacin testing.  相似文献   
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Summary A novel restriction fragment, which was not present in either parent's mitochondrial DNA, was cloned from the mitochondrial genome of a somatic hybrid Petunia line. This fragment resulted from interspecific recombination between homologous mitochondrial DNA regions of the parental plants, Petunia line 3704 and line 3688. Hybridization with a cloned Petunia atp9 gene revealed that the regions involved in recombination carry atp9 coding sequences. Intragenomic recombination within the parental mitochondrial genomes was not detected between the atp9 regions which recombined following protoplast fusion.  相似文献   
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