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61.
The exercise electrocardiograms of 44 asymptomatic men with acquired left bundle branch block were analyzed for changes in R wave amplitude. Results were correlated with findings on selective coronary angiography. There were two subgroups: 7 men with significant angiographic coronary artery disease (Group I) and 37 with normal coronary angiograms (Group II). Exercise induced an increase in R wave amplitude in all seven men with coronary artery disease but in only 10 of the 37 men without significant coronary artery disease. This criterion thus had a sensitivity of 100 percent but a poor specificity of 73 percent, a predictive value of 41 percent and an accuracy rate of 77 percent for the diagnosis of coronary artery disease. The greater the increase in R wave amplitude the greater was the likelihood of some degree of left ventricular dysfunction as measured by wall motion abnormalities and elevated left ventricular end-diastolic pressure. The increase in R wave amplitude with exercise appears to be a sensitive test in identifying coronary artery disease in asymptomatic men with acquired left bundle branch block.  相似文献   
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The epidemiological status of HCV in Europe, and in particular in Mediterranean countries, is continuously evolving. The genotype distribution is related to improvement of healthcare conditions, expansion of intravenous drug use and immigration. We review and characterize the epidemiology of the distribution of HCV genotypes within Calabria, an area of Southern Italy. We focus on the pattern of distinct HCV genotype changes over the last 16 years; particularly subtype 1b and genotype 4. We collected data by evaluating a hospital-based cohort of chronic hepatitis C patients; in addition, we report an update including new patients enrolled during last eight months.  相似文献   
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ObjectivesTo assess regionalization trends and short-term clinical outcomes in patients undergoing radical cystectomy for urothelial carcinoma.Materials and methodsUsing 1996–2009 discharge data from New York (NY), New Jersey (NJ) and Pennsylvania (PA), all patients ≥18 years with urothelial carcinoma undergoing cystectomy were identified using ICD-9 coding. We assigned hospital volume status by quintiles based on relative proportions of cystectomies performed on a per hospital basis in 1996; very low volume hospitals: 0–2 (VLVH), low: 3–4 (LVH), moderate: 5–8 (MVH), high: 9–31 (HVH), and very high: ≥32 (VHVH). Changes in the proportion of procedures performed by volume categories were assessed over time, and patient characteristics were compared between groups.ResultsA total of 14,404 patients met inclusion criteria. For each year increase from 1996 to 2009, the odds of having surgery performed at a VHVH increased by 22% (odds ratio [OR] 1.22, confidence interval [CI] 1.04–1.44). Patients undergoing surgery at a VHVH were less likely to be African American (OR 0.59 [CI 0.39–0.91]), or insured through Medicaid (OR 0.65 [CI 0.50–0.84]) or Medicare (OR 0.84 [CI 0.75–0.94]). Controlling for year treated, total procedures performed, and patient characteristics, median hospital length of stay (HLOS) was shorter (median difference ?0.89 days [CI ?1.12 to ?0.66]), and patients were significantly less likely to die during their hospital stay if treated at a VHVH compared with a VLVH (OR 0.33 [CI 0.22–0.49]).ConclusionsThere has been extensive regionalization of cystectomy to VHVHs in NY, NJ, and PA since 1996. Despite apparent improvements in mortality and HLOS in patients treated at higher volume centers in our sample, future investigations more rigorously adjusting for hospital structural characteristics and patient severity are necessary to confirm these findings. Disparities in access to VHVH care are still evident and must be addressed.  相似文献   
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BackgroundEarly childhood caries (ECC) is prevalent and consequential. Risk assessment tools have been proposed that can be used to identify children who require intensive interventions. In this study, the authors compare four approaches for identifying children needing early and intensive intervention to prevent or minimize caries experience for their accuracy and clinical usefulness.MethodsThe authors screened 229 predominantly low-income Hispanic children younger than 3 years with ECC and 242 without ECC by using the American Academy of Pediatric Dentistry's Caries-risk Assessment Tool (CAT) and the optional screening measure of culturing Streptococcus mutans. The authors compared four approaches (CAT, CAT minus socioeconomic status, CAT minus socioeconomic status plus mutans streptococci [MS] and MS alone) for accuracy and clinical usefulness.ResultsThe results of the CAT demonstrated high sensitivity (100.0 percent) and negative predictive value (NPV) (100.0 percent) but low specificity (2.9 percent) and positive predictive value (PPV) (49.4 percent). The MS culture alone had the highest combination of accuracy and clinical usefulness (sensitivity, 86.5 percent; specificity, 93.4 percent; PPV, 92.5 percent; NPV, 87.9 percent). When we removed the socioeconomic status element, the CAT's performance improved.ConclusionsSalivary culture of MS alone in a population of young, low-income Hispanic childrenoutperformed the CAT and variations on the CAT for test accuracy (sensitivity and specificity) and clinical usefulness (predictive values).Clinical ImplicationsScreening for ECC by using salivary MS cultures and variations on the CAT are promising approaches for identifying children who need early and intensive intervention to prevent or minimize caries experience.  相似文献   
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We present an unusual case of haematogenous osteomyelitis in the diaphysis of the tibia of an adult leading to a subacute presentation with an extracortical abscess. Fluid from the abscess grew methicillin resistant Staphylococcus aureus (MRSA) on culture; MRSA with the same antibiogram had been grown from the patient’s blood seven years earlier following a bowel resection. Drainage of the abscess and curettage of the bone lesion together with appropriate antibiotic therapy led to resolution of the osteomyelitis.  相似文献   
70.
Basset  P; Beuzard  Y; Garel  MC; Rosa  J 《Blood》1978,51(5):971-982
Isoelectric focusing on slabs of acrylamide gel was adapted for the screening of abnormal hemoglobins, the characterization of 70 human variants, and the study of minor fractions of normal hemoglobin. The screening method was as fast and inexpensive as conventional techniques, allowed the simultaneous analysis of some 50 samples of whole blood, and yielded resolution superior to that obtained by other methods with hemolysates. Among the 70 variants, 31 mutants could not be separated from HbS by cellulose acetate electrophoresis. The characterization technique of electrofocusing allowed us to distinguish between most variants. Only one mutant, Hb Galveston, could be confused with HbS. Hb Koln, the most frequent unstable mutant, exhibited a special pattern. HbA1C was separated from HbA. Preliminary results indicate that quantitation of HbA1C by gel scanning is feasible.  相似文献   
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