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991.
Genome-wide linkage analysis in the Boston Early-Onset Chronic Obstructive Pulmonary Disease (COPD) Study has demonstrated significant evidence of linkage to chromosome 8p for forced expiratory volume in 1 second, an important COPD-related phenotype. In this study, we sought to fine map the linkage peak and to test variants in two candidate genes for association with COPD and related traits. In a variance component linkage analysis on chromosome 8, including seven additional short tandem repeat markers, the logarithm of the odds of linkage score was reduced from 3.30 to 1.80 (at 1 cM). Five single nucleotide polymorphisms (SNPs) in Defensin Beta-1 (DEFB1) were genotyped in the Boston Early-Onset COPD Study families; none was significantly associated. Four SNPs and an insertion-deletion polymorphism in Macrophage Scavenger Receptor-1 (MSR1) were also genotyped in the family-based study. A coding variant (Pro275Ala) was marginally associated with two qualitative airflow obstruction traits (p < or = 0.02). This SNP showed a trend toward association in a case-control study comparing participants in the National Emphysema Treatment Trial to smoker controls (p = 0.07). Despite the reduced support for linkage upon further analysis, it remains possible that chromosome 8p contains a gene that influences COPD susceptibility. There is marginal, though not convincing, evidence for association with MSR1.  相似文献   
992.
OBJECTIVE: To identify the prognostic factors of relapse and/or death during the course of primary small-vessel vasculitides (PSVV), and to differentiate their prognostic relevance by the type of vasculitis. METHODS: Seventy-five patients were retrospectively followed up after diagnosis: 36 with Wegener's granulomatosis (WG), 23 with Churg-Strauss syndrome (CSS), and 16 with microscopic polyangiitis. Cox regression analysis was used to identify the significant predictors of relapse and death. RESULTS: Gastrointestinal (GI) involvement was associated with an increased risk of relapse, mainly in the patients with CSS, whereas renal disease and perinuclear antineutrophil cytoplasmic antibody positivity were correlated with a lower risk of relapse. Presence of nasal Staphylococcus aureus tended to increase the risk of relapse in CSS [hazard ratio (HR) 4.45, p = 0.087], but to decrease it in WG (HR 0.12, p = 0.066). Older age, renal and hepatic involvement, erythrocyte sedimentation rate >or= 100 mm/h, and serum creatinine level >or= 1.5 mg/dl were all related to higher risk of death in univariate analysis; however, only cerebral (HR 8.52, p = 0.021) and hepatic involvement (HR 4.40, p = 0.028) and serum creatinine level >or= 1.5 mg/dl (HR 5.72, p = 0.044) were independently correlated with an unfavorable prognosis for survival. The risk of death associated with each of these indicators did not depend on the form of PSVV. CONCLUSION: GI involvement increases the risk of relapse in CSS, whereas the prognostic significance of nasal S. aureus in terms of relapse seems to be opposite in patients with CSS and those with WG. Patients with cerebral, hepatic, and renal involvement have the poorest prognosis for survival. Our data do not show that the prognostic relevance of these factors depends on the form of PSVV.  相似文献   
993.
994.
Anemia is a frequent extraenteric complication of inflammatory bowel disease (IBD, Crohn's disease and ulcerative colitis). A systematic review of the literature shows that the overall prevalence of anemia ranges from 8.8% to 73.7% but differs whether in a setting of Crohn's disease or ulcerative colitis. A disabling complication of IBD, anemia worsens the patient's general condition and quality of life, and increases hospitalization rates. Different factors, including vitamin B12 and folic acid deficiency, bone marrow suppression secondary to drug therapy, autoimmune hemolytic anemia and the coexistence of myelodysplastic syndromes are involved in the pathogenesis of anemia in IBD. The main types of anemia in IBD are iron deficiency anemia and anemia accompanying chronic diseases. Correct diagnostic definition of anemia is a fundamental step in guiding the choice of therapeutic options, since the co-presence of different pathogenetic factors may sometimes require a more complex treatment plan. A review of anemia in IBD, its pathogenetic features, epidemiology, diagnosis and therapy based on evidence from recent studies is the focus of this article.  相似文献   
995.
No study has evaluated the performance of BRCA1/2 mutations prediction models in male breast cancer (MBC) series. Although rare, MBC deserves attention because male and female breast cancers share many characteristics, including the involvement of genetic predisposition factors such as BRCA1/BRCA2 mutations. Indeed, the occurrence of MBC is a commonly used criterion to select families for BRCA mutation testing. We evaluated the performance and clinical effectiveness of four different predictive models in a population-based series of 102 Italian MBC patients characterized for BRCA1/2 mutations. Sensitivity, specificity, and positive and negative predictive values (PPV, NPV) were calculated for each risk model at the 10% threshold. The area under the ROC (AUC) curves and its corresponding asymptotic 95% CIs were calculated as a measure of the accuracy. In our study, the BRCAPRO version 5.0 had the highest combination of sensitivity, specificity, NPV and PPV for the combined probability and for the discrimination of BRCA2 mutations. In individuals with negative breast–ovarian cancer family history, BRCAPRO 5.0 reached a high discriminatory capacity (AUC=0.92) in predicting BRCA2 mutations and showed values of sensitivity, specificity, NPV and PPV of 0.5, 0.98, 0.97 and 0.67, respectively, for the combined probability. BRCAPRO version 5.0 can be particularly useful in dealing with non-familial MBC, a circumstance that often represents a challenging situation in genetic counseling.  相似文献   
996.
We observed a significant increase of Pseudomonas aeruginosa bacteremias during 2002. Eighty-five microbiological samples were taken from different potential sources of infection. Twenty-nine out of 46 specimens obtained from water taps, shower heads and siphons tested positive for Pseudomonas aeruginosa. Weekly pharyngeal and rectal swabs in high risk patients, use of tap water after running the tap for at least 5 minutes and use of weekly disposable sterile filters in all taps and showers resulted in a significant decrease in Pseudomonas aeruginosa bacteremias. Moreover, we observed a significant reduction in Pseudomonas aeruginosa-positive surveillance cultures after implementation of these measures.  相似文献   
997.
998.
AIMS: Transesophageal Doppler echocardiography (TEE) is a useful tool to investigate pulmonary venous flow (PVF) velocity, which is altered in patients with mitral stenosis (MS). This study used TEE to analyze the variations in the PVF pattern after successful valvar dilatation in MS patients. METHODS/RESULTS: A total of 15 MS patients, mean age 27.2 years, underwent effective percutaneous balloon valvotomy (PBV). All were submitted to TEE before and after PBV. TEE assessed systolic (SPFV) and diastolic (DPFV) peak flow velocities and their ratio (SPFV/DPFV), time-velocity integrals (STVI and DTVI) and their ratio, and diastolic flow deceleration (DFD). Valvotomy yielded statistically significant increases (P < or = 0.05) in the SPFV: increase on average by 67% and STVI by 120%, as well as in the diastolic component: increased on average by 35%, DTVI by 33%, and DFD by 75%. CONCLUSION: TEE demonstrated that PBV induced a global increase in velocities of PVF, probably related to improvement of left atrial emptying.  相似文献   
999.
BACKGROUND: Rabeprazole is a proton pump inhibitor which is particularly suitable for use in short-term Helicobacter pylori eradication treatment. Levofloxacin-based H. pylori eradication regimens have shown good efficacy and very few side effects. Shorter treatment and absence of significant side effects should improve compliance to therapy and increase the Hp H. pylori eradication rate. AIMS: To evaluate the effectiveness of 2 rabeprazole-based H. pylori eradication regimens in an open-label, randomized study carried out in a clinical practice setting. METHODS: One hundred sixty-nine consecutive, treatment-naive patients with H. pylori infection were randomized to receive rabeprazole (20 mg, bid), levofloxacin (500 mg, bid), and tinidazole (500 mg, bid) for either 4 [4-d rabeprazole, levofloxacin, tinidazole (RLT), n=85] or 7 days (7-d RLT, n=84). Before treatment, all patients underwent upper digestive endoscopy. Cure rates were assessed by means of C-urea breath test. and were compared with the eradication rate obtained with standard triple therapy in our Unit (ie, 78%) and average eradication rate reported in the literature (ie, 79%). RESULTS: The intention-to-treat eradication rates were 94% [87% to 98%, 95% confidence interval (CI)] and 95% (88% to 99%, 95% CI) in the 4-day RLT and 7-day RLT regimens, respectively, whereas per-protocol eradication rates were 95% (88% to 99%, 95% CI) in the 4-day RLT and 96% (90% to 99%, 95% CI) in the 7-day RLT. Both treatment regimens obtained significantly higher eradication rates as compared with standard triple therapy. The 4-day RLT showed significantly fewer side effects. CONCLUSIONS: In a clinical practice setting, both 4-day and 7-day rabeprazole, high-dose levofloxacin, tinidazole-based regimens achieved relevant H. pylori eradication rates in treatment-naive patients. The lower number of side effects makes the shorter treatment regimen preferable over the conventional 7-day treatment.  相似文献   
1000.
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