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51.
This report is from a 10-year cohort study of community-dwelling elderly men and women. Mean age at the time of entry into the study was 79 years. Annual chest x-ray studies were performed, and data are presented regarding prevalence, incidence, and prognosis of cardiomegaly. Cardiomegaly was defined as a transverse diameter of the cardiac silhouette greater than or equal to 50% of the transverse diameter of the chest (increased cardiothoracic ratio). At the time of entry into the study 110 subjects (23%) had cardiomegaly. After 10 years, 51% of the subjects with cardiomegaly at baseline died compared with 33% of the subjects without cardiomegaly (mortality rate = 9.1 vs 4.8/100 person-years respectively; p = 0.014). Cardiovascular disease incidence was also higher for those with preexisting cardiomegaly at baseline (rate 9.1 vs 6.1/100 person-years; p = 0.0001). According to the Cox proportional hazards regression analysis, age, cardiomegaly, diabetes, and prior evidence of myocardial infarction were independent predictors for death in this cohort. Similarly, the best predictive variables for cardiovascular disease were age, diabetes, prior evidence of myocardial infarction, and cigarette smoking. Of the 359 subjects without cardiomegaly at baseline, 108 (30%) showed evidence of new cardiomegaly, and their risk of cardiovascular disease was 1.8 times that of subjects whose test results were negative for cardiomegaly throughout the study (p = 0.003). Thus cardiomegaly, as defined by an increased cardiothoracic ratio on x-ray films, irrespective of cause, is associated with a poor prognosis in very elderly men and women.  相似文献   
52.
Chronic volume overload is associated with dilatation and eccentric hypertrophy of the left ventricle (=ventricular remodeling). With the dilatation of the left ventricle and the shift of the pressure-volume-relationship to the right, the filling pressures can be kept normal despite severe regurgitation. Therefore, the patient with aortic regurgitation can remain asymptomatic over many years. Thus, the indication for aortic valve replacement in patients with severe aortic regurgitation is sometimes difficult and may lead to problems to choose the optimal time point for operation. As a general rule, symptomatic patients with severe aortic regurgitation should be operated as soon as possible. In asymptomatic patients with significant dilatation of the left ventricle and reduction of systolic pump function the therapy of choice is aortic valve replacement. Asymptomatic patients with normal left ventricular function have usually a good prognosis with a yearly mortality rate of approximately 0.04%. However, in the presence of significant dilatation of the left ventricle, i. e. enddiastolic chamber diameter more than 70 mm respectively endsystolic diameter more than 50 mm, patients have to be checked on a regular basis, i. e. in yearly intervals to detect left ventricular dysfunction in due time. According to the literature, asymptomatic patients with severe aortic regurgitation develop left ventricular dysfunction in a yearly rate of 4%. However, approximately 50% of all patients are even after 10 years asymptomatic. The indication for aortic valve replacement is given when the patient shows a deterioration of left ventricular function or becomes symptomatic. Valve replacement is also indicated in patients with an ejection fraction below 50% and/or endsystolic chamber diameter of more than 55 mm. Therapy of choice in symptomatic patients with severe aortic regurgitation is aortic valve replacement. In asymptomatic patients, operation depends on the degree of chamber dilatation respectively the severity of left ventricular dysfunction. In patients with severe aortic regurgitation but without clinical symptoms and moderate enlargement of the left ventricle regular check-ups in yearly intervals are indicated. In the presence of severe left ventricular dilatation check-ups should be performed on a half-year basis to prevent irreversible damage to the heart muscle.  相似文献   
53.
The prevalence, incidence and prognosis of recognized and unrecognized Q-wave myocardial infarction (MI) was assessed in an 8-year prospective study of 390 community-based subjects (age 75 to 85 years at entry, mean 79 years). Subjects were studied at baseline and with annual follow-up electrocardiographic (ECG) exams. At baseline, 7.9% had a history of MI without ECG evidence, 6.4% had ECG evidence of Q-wave MI without clinical history, 4.1% had both clinical history and ECG evidence and 81.5% had neither history nor ECG evidence (control subjects). After an average follow-up period of 76.2 months, the total mortality rate was 5.9/100 person-years for subjects with some evidence of MI at baseline versus 3.9 in the control group (p = 0.059). The incidence of cardiovascular disease in subjects with evidence of MI was 8.8/100 person-years versus 4.7 among control subjects (p = 0.002). During the follow-up period, 115 new Q-wave MIs occurred (50 unrecognized, rate 2.4/100; 65 recognized, rate 3.2/100). There was no difference in mortality and morbidity outcome between subjects with recognized and unrecognized MIs. Those with only a history of MI at baseline had a threefold greater risk of a new MI (recognized and unrecognized) than the control group (p = 0.003). Unrecognized Q-wave MI is a common occurrence in the "old old" with subsequent morbidity and mortality prognosis comparable to that of recognized MI. History of MI alone in this age group is also associated with an increased risk of MI, suggesting the need for better diagnostic markers of myocardial ischemia in the old.  相似文献   
54.
Lactoferrin (Lf) was shown to exhibit its antiviral activity at an early phase of viral infection and a mechanism whereby the protein interacts with host cell surface molecules has been suggested. In this study, human Lf (HLf) and seven HLf‐derived synthetic peptides (HLP) corresponding to the N‐terminal domain of the native protein (1–47 amino acids sequence) were assayed for their capacity to prevent hepatitis B virus (HBV) infection and replication using the HepaRG and HepG2.2.2.15 cell lines. Of the series tested, four peptides showed 40–75% inhibition of HBV infection in HepaRG cells, HLP1–23, containing the GRRRR cationic cluster, being the most potent. Interestingly, this cluster is one of the two glycosaminoglycan binding sites of the native HLf involved in its antiviral activity; however, the mechanism of the HLP1–23 action was different from that of the full‐length protein, the peptide inhibiting HBV infection when pre‐incubated with the virus, while no effect was observed on the target cells. It is suggested that the cationic cluster is sufficient for the peptide to interact stably with negatively charged residues on the virion envelope, while the absence of the second glycosaminoglycan binding site prevents its efficient attachment to the cells. In conclusion, this peptide may constitute a non‐toxic approach for potential clinical applications in inhibiting HBV entry by neutralizing the viral particles. J. Med. Virol. 85:780–788, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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Hypertension has been reported in 8-32% of HIV-infected individuals. Large interarm blood pressure differences (IABPD) may cause misclassification of blood pressure (BP) status. The objectives of this study were to determine the magnitude and factors associated with IABPD in HIV-infected women and uninfected controls. Using automated devices, two BP recordings were measured and averaged from each arm in Brooklyn enrollees of the Women's Interagency HIV Study. Absolute IABPD was calculated for each patient. Among 335 subjects, 238 were HIV infected and 97 were uninfected. Mean systolic and diastolic IABPD were 6 +/- 5 mm Hg and 4 +/- 3 mm Hg, respectively. Twenty-six percent of subjects had systolic IABPD >10 mm Hg and 6% had systolic IABPD >20 mm Hg. Fifteen percent of subjects had diastolic IABPD >10 mm Hg. Interarm BP differences were not associated with HIV serostatus, CD4(+) cell count, and use of highly active antiretroviral therapy. Systolic IABPD >20 mm Hg was associated with obesity (ORadj 5.37, 95% CI 1.47, 19.65), and LDL cholesterol above 160 (ORadj 9.12, 95% CI 2.53, 32.88). Right arm BP measurement resulted in 10% of subjects with high/uncontrolled BP. Bilateral arm BP measurement increased the yield to 15% (p < 0.001). In conclusion, systolic and diastolic IABPD are common and appear to be of clinically important magnitude. Systolic IABPD are related to cardiovascular risk factors but not to HIV-related factors. Bilateral BP determination is important to detect and manage hypertension as well as for accurate cardiovascular risk assessment.  相似文献   
60.
AIM: To evaluate outcomes of radiofrequency ablation(RFA) therapy for early hepatocellular carcinoma(HCC) and identify survival- and recurrence-related factors. METHODS: Consecutive patients diagnosed with early HCC by computed tomography(CT) or magnetic resonance imaging(MRI)(single nodule of ≤ 5 cm, or multi-(up to 3) nodules of ≤ 3 cm each) and who underwent RFA treatment with curative intent between January 2010 and August 2011 at the Instituto do Cancer do Estado de S o Paulo, Brazil were enrolled in the study. RFA of the liver tumors(with 1.0 cm ablative margin) was carried out under CT-fluoro scan and ultrasonic image guidance of the percutaneous ablation probes. Procedure-related complications were recorded. At 1-mo post-RFA and 3-mo intervals thereafter, CT and MRI were performed to assess outcomes of complete response(absence of enhancing tissue at the tumor site) or incomplete response(enhancing tissue remaining at the tumor site). Overall survival and diseasefree survival rates were estimated by the Kaplan-Meier method and compared by the log rank test or simple Cox regression. The effect of risk factors on survival was assessed by the Cox proportional hazard model. RESULTS: A total of 38 RFA sessions were performed during the study period on 34 patients(age in years: mean, 63 and range, 49-84). The mean follow-up time was 22 mo(range, 1-33). The study population showed predominance of male sex(76%), less severe liver disease(Child-Pugh A, n = 26; Child-Pugh B, n = 8), and single tumor(65%). The maximum tumor diameters ranged from 10 to 50 mm(median, 26 mm). The initial(immediately post-procedure) rate of RFAinduced complete tumor necrosis was 90%. The probability of achieving complete response was significantly greater in patients with a single nodule(vs patients with multi-nodules, P = 0.04). Two patients experienced major complications, including acute pulmonary edema(resolved with intervention) and intestinal perforation(led to death). The 1- and 2-year overall survival rates were 82% and 71%, respectively. Sex, tumor size, initial response, and recurrence status influenced survival, but did not reach the threshold of statistical significance. Child-Pugh class and the model for end-stage liver disease score were identified as predictors of survival by simple Cox regression, but only Child-Pugh class showed a statistically significant association to survival in multiple Cox regression analysis(HR = 15; 95%CI: 3-76 mo; P = 0.001). The 1-and 2-year cumulative disease-free survival rates were 65% and 36%, respectively. CONCLUSION: RFA is an effective therapy for local tumor control of early HCC, and patients with preserved liver function are the best candidates.  相似文献   
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