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A genetic linkage map of human chromosome 21q (HC21q) containing 43 markers genotyped by the polymerase chain reaction in the CEPH pedigrees is presented. The markers placed on this map are highly polymorphic with an average heterozygosity of 61%. The average interval size of the markers localized at 1000:1 odds is 2.5 cM. The map has a total length of 65.5 cM, with male and female lengths of 47.7 and 83.3 cM, respectively. The genotypes used in the construction of this map were subjected to rigorous error checking, which is reflected in the shorter map length compared to previous maps; the estimated error rate in genotyping is less than 0.04%. As noted in previous linkage maps there is increased recombination in females on proximal HC 21q and in the male in a region near the telomere. This map of HC 21 represents a highly informative and dense meiotic linkage map and will be useful in linking disease phenotypes to loci on this chromosome.  相似文献   
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Here we are presenting the case of a 70-years-old woman who has hepatic cirrhosis anti-HCV and insulin-dependent diabetes mellitus, without relevant epidemiologic ascendants or previous transfusions and HBV, HIV negatives. On admission to our hospital she showed signs of autoimmune hemolytic anaemia (AHA) which was confirmed by positive direct Coombs test and an improvement in blood test after corticoid treatment. Having discarded other possible causes such as drugs infectious diseases or essential mixed cryoglobulinemia (CME), we put forward the possible association between AHA and infection by HCV, where AHA was an extrahepatic immunological manifestation of HCV. This fact has never been brought to light in previous medical literature.  相似文献   
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BACKGROUND: There is controversy over whether colonization with drug-resistant organisms is a contraindication to lung transplantation. METHODS: We undertook a retrospective review of the results of lung transplantation for patients with cystic fibrosis (CF) at Duke University Medical Center. RESULTS: As of May 1996, 21 patients with CF underwent bilateral lung transplantation. The first patient died within 24 h of transplantation from sepsis due to Stenotrophomonas maltophilia. Of the remaining 20 patients, 17 (85%) are alive and in stable condition. The three deaths were related primarily to bronchiolitis obliterans at 4 and 18 months in two patients and to cytomegalovirus pneumonitis at 5 months in the other patient. The 17 surviving patients have been followed up for a mean of 13 months (range, 0.5 to 34 months). Most of them were colonized and infected with multidrug-resistant organisms before transplantation. Following transplantation, 11 patients had complications from infections. One patient had bacteremia due to a panresistant Burkholderia cepacia and was treated successfully. Two patients had bacteremia and wound infection due to Burkholderia gladioli, previously thought to be pathogenic only in plants. Both patients were treated successfully. Of the six patients with Aspergillus fumigatus isolated from cultures before transplantation, only one had invasive disease following transplantation and responded to treatment. CONCLUSION: The organisms present before transplantation were not the primary cause of mortality in our patient population. Our findings suggest that lung transplantation should be considered in CF patients infected with multidrug-resistant organisms.  相似文献   
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BACKGROUND: Hypertension and hypercholesterolemia are frequently associated with this leading to considerable cardiovascular risk. METHODS: An open parallel randomized study was performed in which the effects of doxazosin, an alpha-adrenergic blocker and enalapril, an inhibitor of the angiotensin converting enzyme were compared in 70 patients with essential high blood pressure and plasma cholesterol levels greater than 240 mg/dl. Following 2-4 weeks of placebo administration the patients were randomly treated with one of the two drugs. When required doses were increased and hydrochlorothiazide added until blood pressure lower than 160/95 mmHg was achieved. After this period the patients were observed for a minimum of 8 weeks. The mean length of the study was of 22 weeks. RESULTS: Both drugs significantly reduced blood pressure without modifying cardiac frequency. Doxazosin tended to favorably modify the lipid profile of the plasma while enalapril significantly reduced the levels of cholesterol, lipids and high density lipoproteins (HDL). Upon termination of the study the total HDL/cholesterol index increased 8.6% in those treated with doxazosin and decreased 5.5% in those receiving enalapril (p < 0.05). CONCLUSIONS: Although doxazosin and enalapril are potent antihypertensive drugs, the effects on plasma lipid obtained with doxazosin indicate that a reduction in cardiovascular risk was achieved with this drug in the patients included in this study.  相似文献   
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The aim of this study was to document plasma retinol status and nocturnal vision in ten eutrophic adolescents with cystic fibrosis (CF) receiving daily retinol supplementation. Plasma retinol, alpha and beta carotenes and retinol binding protein were measured in ten clinically stable CF patients (mean age: 14.3 years; Shwachman score: 80-100). Nocturnal vision evaluation was performed with a Beyne optometer. Plasma retinol (mean 0.42 +/- 0.16 mg/l), alpha carotene and beta carotene levels were below the lower limit of normal in all but one patient. Five out of ten patients with normal standard opthalmological examination presented a poor (n = 3 patients) or a pathological (n = 2) dark adaptation test. These two patients showed a dramatic increase in nocturnal vision after 1 year of adapted retinol supplementation. CONCLUSION: Low vitamin A levels occur frequently in clinically stable, eutrophic and retinol supplemented CF adolescents. Since vitamin A deficiency is associated with poor nocturnal vision and since this pattern can be reversed by adapted retinol supplementation, we recommend monitoring plasma vitamin A levels in CF patients and evaluation of dark adaptation in retinol deficient patients.  相似文献   
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The purpose of this study was to examine the factors which affect the level of fatigue among patients participating in clinical trials in which this symptom had been assessed with the EORTC QLQ-C30. Data were assembled from 2390 patients in ten clinical trials in which the QLQ-C30 had been used to assess baseline and on-study quality of life. The relationship between the level of fatigue reported by the patients on the fatigue scale of this questionnaire and patient and disease characteristics was assessed in univariate and multivariate cross-sectional analyses. In addition, changes in fatigue scores were compared in a longitudinal analysis among patients on two arms of an anti-emetic trial whose emesis control was markedly different. Baseline fatigue levels differed substantially among patients taking part in the different trials. Factors associated with greater fatigue severity on univariate analysis included: female gender, presence of metastatic disease, and poorer performance status. In addition, on multivariate analyses the oldest patients were found to have less fatigue, as were patients with breast cancer, while patients with ovarian and lung cancer experienced greater fatigue. Patients on the arm of the anti-emetic trial in which emesis was better controlled showed significantly less increase in fatigue after receiving chemotherapy. The fatigue scale of the QLQ-C30 appears to provide a useful approach to assessing this important symptom. The relationships found between fatigue and patient and disease characteristics need further exploration as does the degree to which the QLQ-C30 fully captures this dimension of quality of life.  相似文献   
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Male strain A/J mice were exposed for 6 h a day, 5 days a week to environmental tobacco smoke (ETS) generated from Kentucky 1R4F reference cigarettes. Chamber concentrations were 87 mg/m3 of total suspended particulate matter (TSP), 246 p.p.m. of CO and 16 mg/m3 of nicotine. After 5 months, 33% of the ETS exposed and 11% of the control animals had one or several lung tumors; the difference was statistically not significant. A second group of animals exposed for 5 months to ETS was allowed to recover for another 4 months in filtered air. When they were killed, 85% of the ETS animals had lung tumors (average number per lung: 1.4 +/- 0.2), whereas in the control group 38% had lung tumors (average number of lung tumors in all animals 0.5 +/- 0.2). The differences in tumor incidence and multiplicity were statistically significant. More than 80% of all tumors were adenomas, the rest adenocarcinomas. When animals were pretreated with a carcinogen, lung tumor multiplicity was lower in the ETS exposed animals after 5 months compared with controls injected with a carcinogen and kept in air. However, after an additional 4 month recovery period in air, lung tumor multiplicities were the same in ETS plus carcinogen exposed mice as in carcinogen-treated air-exposed controls. Histopathologic and morphometric analysis of the lung tissue failed to reveal any differences between ETS exposed and control animals. However, immediately after ETS exposure, immunohistochemistry revealed increased staining for CYP1A1 in airway epithelia and lung parenchyma; following recovery in air, the staining disappeared again. Analysis of cell kinetics showed an initial burst of increased DNA synthesis in the epithelial cells of the airways and a smaller early positive response in the parenchyma. Feeding of butylated hydroxytoluene during ETS exposure did not modulate lung tumor development. It was concluded that ETS is a pulmonary carcinogen in strain A/J mice.  相似文献   
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A cryptic multidrug resistance (MDR) system in Stenotrophomonas maltophilia, the expression of which is selectable by tetracycline, is described. Tetracycline resistance was the consequence of active efflux of the antibiotic, and it was associated with resistance to quinolones and chloramphenicol, but not to aminoglycosides or beta-lactam antibiotics. MDR is linked to the expression of an outer membrane protein (OMP54) both in a model system and in multidrug-resistant clinical isolates.  相似文献   
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