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41.
The prevalence of orthostatic hypotension (OH) among the community-dwelling elderly is high, but the head-up tilt testing in the laboratory setting is time-consuming and costly. However, an objective index for screening for OH among older people recruited from community settings has not yet been established. Therefore, this study conducted to identify factors that can reveal OH among the elderly recruited from a community setting. A total of 86 people aged ≥ 60 years underwent head-up tilt testing with beats-by-beats blood pressure measurements at Center for elderly fitness and disease/disability prevention research at Nagoya University School of Health Sciences. OH was defined a reduction in systolic blood pressure of at least 20 mmHg or in diastolic blood pressure of at least 10 mmHg within 3 min of raising the head. Associations among anthropometric measurements, fitness parameters and OH were analyzed using multiple logistic regression. Calf mass index (CMI) (OR=0.488, 95% CI; 0.32-0.743, P<0.001) and alpha-blockers (=0.078, 95% CI; 0.007-0.883, P<0.05) were related to OH. The area under the ROC curve was 74.4% (95% CI; 62.8-86.0, P<0.001) and the discriminatory CMI value was 21.2. Our findings suggest that the CMI can be used for screening for OH in the community-dwelling elderly. This information can help clinicians and health care providers working with older people to identify those at risk of OH.  相似文献   
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We reviewed 109 consecutive patients with cancer of the hypopharynx or cervical oesophagus who underwent free flap transfer for immediate reconstruction after total pharyngolaryngo-oesophag-ectomy. The free flaps used were either free jejunal (n = 70) or radial forearm flaps (n = 39). Significantly more fistulas (3/70 compared with 15/39, p &lt; 0.0001) and strictures (6/64 compared with 13/33, p = 0.0008) developed in the radial forearm than the jejunal flap group. However, functional donor site morbidity was minimal and there were no cases of total flap necrosis in the forearm flap group. We consider that the free jejunal flap should be the first choice for total reconstruction of pharyngo-oesophageal defects. However, the forearm flap is suitable for elderly, high risk patients, because it is less invasive and has minimal donor site morbidity, which facilitates early recovery.  相似文献   
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Journal of Interventional Cardiac Electrophysiology - Cardiac conduction disturbance necessitating pacemaker implantation is common among elderly patients. However, patients often have...  相似文献   
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BACKGROUND AND AIM: In order to evaluate loss of the p53 gene more precisely, we performed dual-color fluorescence in situ hybridization (dual-color FISH) for chromosome 17 and p53 gene together with DNA polymorphism analysis of the p53 gene in hepatocellular carcinoma (HCC). METHODS: Dual-color FISH using probes specific for the centromere of chromosome 17 and the p53 gene was performed for 41 HCC and DNA polymorphism analysis was also performed for them. RESULTS: Of the 34 HCC tested by dual-color FISH, 20 had loss of at least one p53 gene (58.8%). In contrast, of the 32 HCC tested by DNA polymorphism analysis, 23 gave informative results, among which only eight had loss of heterozygosity (LOH) of the p53 gene (34.8%). Notably, among 14 cases positive for loss of the p53 gene by dual-color FISH, seven cases were negative for LOH of the p53 gene. Moreover, dual-color FISH revealed that the percentage of cells that lost at least one p53 gene increased as the HCC became less differentiated (P < 0.01), whereas LOH did not reveal any such correlation. CONCLUSIONS: These data suggest that loss of the p53 gene was present in a considerable number of HCC, and diversity of the p53 gene aberration increases with progression of HCC. Dual-color FISH is an effective method for detection of p53 gene aberration, and it can provide new insight into oncogenesis in HCC.  相似文献   
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Ammonium sulfate, as well as potassium phosphate, can be used to measure solubility differences between hemoglobin S and hemoglobin A. In addation, the solubility of deoxyhemoglobin C(Harlem) in 1.96 M phosphate has a markedly different temperature dependence from that of deoxyhemoglobin S. This observation indicates that the solubility measurement is quite sensitive to changes in protein structure. Because of the large degree of comparability between the solubility and the aggregation of deoxyhemoglobin S, solubility was used to measure the effectiveness of organic compounds as noncovalent modifiers of deoxyhemoglobin S aggregation.Organic solvents (ethanol, dimethylsulfoxide, 1,4-dioxane, dimethylformamide) alter the solubility characteristics of deoxyhemoglobin S in 1.96 M phosphate buffer, pH 7.0. The concentrations of solvent necessary to provide a half-maximal effect are remarkably similar (about 0.5 M), although the chemical nature of these compounds is quite different. The effect of these solvents must be to prevent the noncovalent bond formation necessary to produce the insoluble hemoglobin precipitate, perhaps by altering the water structure around the deoxyhemoglobin S molecules. In addition to these organic solvents, guanidine hydrochloride and urea, two well-known protein denaturants, were studied. Guanidine hydrochloride was as effective as the best organic solvent in increasing the solubility of deoxyhemoglobin S; urea was far less effective. Studies in vitro with intact erythrocytes from individuals homozygous for hemoglobin S showed that sickling is decreased up to 50% by treatment with ethanol. This offers further evidence that solubility is monitoring a phenomenon similar to the aggregation of deoxyhemoglobin S inside erythrocytes. While use of these particular compounds in vitro would seem to have no clinical implications, these studies do suggest that the use of chemicals that do not modify hemoglobin S covalently should be explored in efforts to prevent deoxyhemoglobin S aggregation.  相似文献   
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Endothelial cell damage causes massive hepatic necrosis as a result of fibrin deposition in the hepatic sinusoids. When a stable analog of prostaglandin I2, beraprost sodium, was administered to rats given either dimethylnitrosamine, carbon tetrachloride, or endotoxin followingCorynebacterium parvum administration, the hepatic necrosis produced in each was attenuated, but to a greater extent in the dimethylnitrosamine and endotoxin/Corynebacterium parvum models, where fibrin deposition in the hepatic sinusoids occurs, as compared to the carbon tetrachloride model, where such fibrin deposition does not occur. Beraprost sodium reduced the expected increase of portal venous pressure in the endotoxin/Corynebacterium parvum model without affecting plasma thrombin-antithrombin III complex levels. Beraprost sodium also significantly reduced cell killing of both isolated rat hepatocytes and hepatic sinusoidal endothelial cells exposed totert-butyl hydroperoxide when compared to controls. Beraprost sodium could prove to be a therapeutic candidate for the treatment of hepatic necrosis, particularly in cases associated with fibrin deposition in the hepatic sinusoids because of its fibrin clot-clearning action.  相似文献   
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