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Aim: The Clinical Dementia Rating (CDR) is an assessment of dementia severity based on observations of activities of daily living, and a CDR of 0.5 (CDR 0.5) represents questionable dementia. A combination of the Cognitive Abilities Screening Instrument (CASI) and the Trail Making Test (TMT) scores discriminated CDR 0.5 subjects from healthy participants with a high degree of accuracy. We investigated the neurological background of CDR 0.5 subjects by correlating CASI and TMT scores with regional cerebral blood flow (rCBF) as measured by single photon emission computed tomography (SPECT). Methods: From a community‐based cohort, 22 CDR 0.5 participants were recruited. CASI and TMT scores, rCBF measure using [123I]‐N‐isopropyl‐p‐iodoamphetamine and SPECT were obtained. We evaluated the relationships between the CASI domain scores, between TMT scores and rCBF in a regions‐of‐interest‐based analysis, and voxel‐based analysis using Statistical Parametric Mapping 5 software. Results: We found that lower rCBF in the left medial temporal cortex correlated with a decreased CASI domain recent memory score both in the regions‐of‐interest and statistical parametric mapping analysis. In both the regions‐of‐interest and statistical parametric mapping analysis, the rCBF in the left prefrontal cortex correlated with CASI domain remote memory and mental manipulation and concentration. Conclusions: Our results indicate that some CDR 0.5 subjects have functional impairments in the medial temporal lobe as well as in the prefrontal cortex, as reflected in the cognitive decline measured by CASI and TMT.  相似文献   
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Background and Aim: Microvascular architecture is a variable characterizing early gastric cancer (EGC) against the background. The aims of the present study were to measure morphological variables of the microvessels and to compare the variables between EGC and the background. Methods: Narrow band imaging (NBI)‐equipped magnifying endoscopic pictures from 32 patients with EGC were used. The endoscopic pictures were taken under maximal magnification and processed for the microvessels in an in‐focus area after correction of image distortion. The segmented microvessels were numbered for microvessel density (counts/mm2) and vascular bed area (% ratio of vascular bed against the region of interest). The microvessels were further processed for a set of skeletonized pixels to count the characteristic points, including end‐points, crossing points, branching points and connecting points. Results: Microvessels in cancer were found to have a significantly larger connected point number (20.5 ± 6.1, P = 0.0002) than those in the background (17.4 ± 3.9). Numbers of the end‐points and branching points were found to be significantly larger in cancer than in the background (end‐points 3.6 ± 0.7 for cancer vs 3.3 ± 0.4 for background, P = 0.0005; branching points 0.8 ± 0.4 for cancer vs 0.7 ± 0.2 for background, P = 0.0014). However, microvessel density, vascular bed area and mean diameter did not significantly differ between cancer and the background. Conclusion: This finding can be considered to reflect the reported observation of an irregular vascular pattern in gastric cancer. This method may provide a means for microvessel morphometry, regardless of the organ studied.  相似文献   
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To assess the biochemical and histological characteristics of hepatitis G virus (HGV) infection, we examined four patients who were infected with HGV only (HGV group), and compared them with 16 patients infected with both HGV and hepatitis C virus (HCV; HGV + HCV group) and 18 patients infected with HCV only (HCV group). Biochemical examination showed a significantly low level of serum alanine aminotransferase (ALT) in the HGV group, and that the gamma-glutamyl transpeptidase (γ-GTP)/ALT ratio in the same group was significantly higher than in the other two groups. Although all three patient groups had a similar degree of liver fibrosis, both the degree of periportal inflammation and total histological activity index were significantly lower in the HGV group than in the other two groups. Fibrous enlargement of the portal tract without lymphoid infiltration and thin fibrous septa was characteristically observed in the HGV group. No significant difference was found between the HGV + HCV group and HCV group. Our results suggest that biochemical and histological changes in HGV infection are very mild and quite different from those of HCV infection.  相似文献   
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To virologically assess the efficacy of interferon therapy in chronic hepatitis C, either 5 or 10 MU/day natural interferon-α (IFNα) was administered to 57 patients with chronic hepatitis C for 38 weeks. A complete and sustained response (CR-SR), as evidenced by the absence of serum hepatitis C virus (HCV)-RNA during the administration period and at 6 months after the final administration of IFNα and a normal GPT level at 6 months after final administration, occurred in 42.6% (23/54) of subjects. Liver tissue was histologically evaluated using the histological activity index (HAI) score before and after the administration period. In CR-SR cases, significant improvements (P <0.01) occurred in periportal necrosis, intralobular necrosis, portal inflammation and total score. A comparison, by HCV genotypes, revealed that CR-SR occurred in 60% (9/15) of subjects with type 2a and 30.3% (10/33) of subjects with type Ib. A comparison by virus concentration revealed that CR-SR occurred in 71.4% (15/21) of those subjects having a virus concentration of < 105 copies/mL, but in only 24.2% (8/33) of those having a virus concentration of > 105 copies/mL. Analysis by a multiple logistic model revealed a strong correlation between the therapeutic effect of interferon therapy and the pre-administration virus concentration (P=0.0061) and genotype (P=0.0015). These results suggest that the preadministration virus concentration and genotype are both key factors affecting the therapeutic effect of interferon therapy in chronic hepatitis C and that the therapeutic effect of interferon is satisfactorily high, irrespective of virus concentration, in subjects with type 2a HCV, but varies depending on virus concentration in subjects with type 1b.  相似文献   
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