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71.
72.
A prospective follow-up study on hepatitis C virus (HCV) infection was conducted in seven haemodialysis units from April 1990 to March 1995. A total of 634 patients were undergoing maintenance haemodialysis in the seven units. Of those, 302 patients participated in the follow-up study; 179 were initially HCV antibody negative and 123 were initially positive. Nine of the 179 initially negative patients became positive for HCV antibody during the follow-up period. In accordance with the appearance of HCV antibody, indicating new infection of HCV, all nine of these patients were diagnosed with HCV viraemia. As no other routes were apparent, HCV infection in all nine patients was likely due to nosocomial transmission. Prevalence of HCV antibody at the start of follow up was significantly higher ( P < 0.001) in haemodialysis units A-C (37.9%) than in haemodialysis units D-G (17.0%). Incidence of new HCV infection was significantly higher ( P = 0.005) in the former units (2.2% per year) than in the latter (0.2% per year). Ten of the 123 patients who were initially positive for the HCV antibody exhibited a loss of reactivity during the follow-up period; of these 10 patients, nine were negative for HCV-RNA from the start of the study. In conclusion, the incidence of new HCV infection seen in patients undergoing haemodialysis suggests that their risk of acquiring HCV infection is directly related to the prevalence of HCV antibody positive patients being treated in the units.  相似文献   
73.
BACKGROUND: The role of calcitonin gene-related peptide (CGRP) in prostate cancer has not been fully understood. Moreover, the serum CGRP level in prostate cancer patients has never been reported. We measured the serum CGRP levels in untreated prostate cancer patients to elucidate its clinical significance. MATERIALS AND METHODS: We used 36 serum samples from prostate cancer patients. All patients had never received any treatment. Serum CGRP was measured by immunoradiometric assay, and we analysed the association between serum CGRP level and clinicopathological factors. RESULTS: Serum CGRP levels in the patients with higher clinical stages and histological grade were significantly higher than in those with lower stages and grade, respectively. But the levels did not correlate with the patient's age, liver or renal functions, serum prostate-specific antigen levels. CONCLUSION: Serum CGRP levels were significantly elevated in the patients with high grade or high stage untreated prostate cancer patients. Measurement of the serum CGRP may be a useful predictor of staging or grading of prostate cancer in the untreated prostate cancer patients.  相似文献   
74.
PURPOSE: The incidence of prostate cancer, benign prostatic enlargement and serum level of prostate-specific antigen (PSA) increase with patient age. Intermediate elevation of PSA in elderly populations is apt to be considered insignificant. We evaluated the impact of PSA and prostate volume on the presence of non-palpable prostate cancer in elderly men with an intermediate level of PSA. MATERIALS AND METHODS: Clinical records of 154 men 70 years or older, with non-cancerous digital rectal examination findings and with serum PSA levels of 2.0-10.0 ng/mL, who underwent initial 6- to 10-core transrectal prostate biopsy, were reviewed for prostate volume, number of biopsy cores, PSA and associated parameters. Stepwise logistic regression and receiver operating characteristic (ROC) models were used to determine the impacts of the parameters on the biopsy results. RESULTS: Overall cancer detection rate was 40/154 or 26.0%. Prostate-specific antigen showed no significant association with the presence of prostate cancer (P = 0.59, Mann-Whitney U-test), while prostate volume did (P < 0.0001). On stepwise logistic regression analysis, prostate volume (P = 0.024, 95% CI 1.008-1.116) and biopsy core density (P = 0.017, 95% CI 4.76-7.12 x 10(6)) were independently associated with a cancer diagnosis, whereas PSA density was not an independent factor for a positive biopsy result. The area under the ROC curve for prostate volume was significantly superior to that of PSA (0.802 vs. 0.529; P = 0.012). CONCLUSIONS: In men 70 years or older with gray zone PSA, prostate cancer patients are equally distributed over any PSA range. Although PSA has less impact on cancer presence than mere prostate volume, prostate cancer would be detected in a substantial proportion of older patients with PSA levels of 2.0-10.0 ng/mL.  相似文献   
75.
The effects of lipophilicity, ion-diffusion potential and membrane surface potential on the uptake of various aliphatic polyamine compounds by rat intestinal brush-border membrane vesicles (BBMV) have been investigated. A valinomycin-induced potassium-diffusion potential (inside-negative) stimulated the initial uptake of diamine compounds, and good correlation was observed between lipophilicity and the amount of diffusion-potential-dependent transport of the diamines. In contrast, because of their much lower lipophilicity, tri- and tetraamine compounds were not affected by the diffusion potential. Tetracaine, which can make the membrane surface potential more positive, inhibited the transport rate of 1,9-nonanediamine, spermidine and spermine by the BBMV. These data suggest that the transport mechanism of diamines is similar to that of monoamine compounds in respect to its dependence on ion-diffusion potential and on the membrane surface potential. The extent of the effect of ion-diffusion potential on the rate of transport of the diamines was closely related to the lipophilicity of the diamine. In contrast, only the surface potential contributed to the transport mechanism of lower lipophilic tri- and tetraamine compounds.  相似文献   
76.
summary EMG spectral shifts anterior temporal and medical masseter muscles were evaluated. Mean power frequency (MPF) shift during fatigue and recovery of 46 healthy subjects and 46 patients with craniomandibular disorder were recorded at the beginning and the end of fatiguing clenching, then 3, 8, 13 and 18min following the fatiguing clenching. The reference clenching force was 80% of each subject's maximal voluntary contraction (MVC). Recording was stopped when subjects felt pain or discomfort. Significance was found between the healthy group (N) and the diseased group (CMD) in the three following points: (i) the mean of MPF values of the masseter muscles at the end of fatiguing clenching; (ii) the recovery pattern of the temporal muscles; and (iii) MPF shift induced by fatiguing clenching. Our results therefore suggest that MPF reflects several aspects of craniomandibular disorders. Thus, measuring fatigue and recovery MPF could be useful in the screening of CMD.  相似文献   
77.
The uptake characteristics of trientine by rat intestinal brush-border membrane vesicles were studied. The uptake characteristics of trientine were similar to those of the physiological polyamines with respect to the excessive accumulation in vesicles, the pH dependency, the temperature dependency and the ineffectiveness of K+ diffusion potential (inside negative). The initial uptake of trientine was saturable with a Km value of 1.13 mM, which was larger than that of spermine and spermidine. Furthermore, the uptake rate of trientine was dose-dependently inhibited by spermine and spermidine. Spermine competitively inhibited the uptake of trientine with a Ki value of 18.6 μM, and it was close to the Km value for spermine (30.4 μM). These data suggested that the uptake of trientine was similar to that of spermine and spermidine in rat small intestinal brush-border membrane vesicles, and these polyamines seem to inhibit the absorption of trientine from the gastrointestinal tract.  相似文献   
78.
BACKGROUND: We retrospectively analysed the outcomes of conservative management of Peyronie's disease and determined the factors predicting successful outcome. METHODS: The study involved 31 patients with Peyronie's disease who were treated at our institute between 1985 and 2003. We assessed the efficacy of vitamin E for the improvement of the symptoms, and the factors which contributed to successful outcome with conservative management using multivariate analysis. RESULTS: There was no statistically significant difference in the relief rate between the vitamin E and no-medication groups. The overall estimated relief rate was 67.5% at 2 years from presentation. The multivariate analysis revealed plaque size to be the only significant factor predicting the relief from all symptoms in patients with conservative management. The rate was 100% in patients having a plaque size of 20 mm or smaller and 20.0% in those having a size of larger than 20 mm (P=0.005). CONCLUSIONS: We could not confirm the benefit of vitamin E for Peyronie's disease. Plaque size was the only significant factor predicting the relief from all symptoms. Patients with larger plaque might fail to respond to the conservative management.  相似文献   
79.
Background: Individuals with late‐life depression can be divided into two categories, those with early and late‐onset depression (EOD and LOD, respectively). It has been reported that LOD has more accentuated subcortical vascular lesions and frontal lobe dysfunction (hypofrontality). The aim of the present study was to examine whether LOD exhibits more prominent hypofrontality than EOD during performance of the word fluency task (WFT) under multichannel near‐infrared spectroscopy (NIRS), a newly developed non‐invasive functional neuroimaging technique. Methods: Eleven patients with EOD, 12 patients with LOD, and 13 healthy controls participated in the study. Clinical symptoms of depression were equivalent in the EOD and LOD groups. Brain magnetic resonance imaging demonstrated more robust subcortical vascular changes in LOD than EOD. The NIRS images were obtained using an ETG‐4000, 52‐channel NIRS system (Hitachi Medical, Tokyo, Japan). Mean changes in oxy‐hemoglobin (oxy‐Hb) were evaluated while the participants performed the phonemic WFT. Results: Healthy controls exhibited clear increases in oxy‐Hb bilaterally throughout the medial to the lateral frontal cortices and the superior temporal areas during the WFT. In contrast, increases in oxy‐Hb were mildly attenuated in EOD and severely attenuated in LOD in most channels. Subsequent analyses revealed that increases in oxy‐Hb in LOD during the WFT was significantly poorer than in EOD in the left lateral portion of the cortex, including the dorsolateral prefrontal and the superior temporal areas. In addition, significant negative correlations were obtained between the age of onset and oxy‐Hb, as well as between subcortical vascular changes and oxy‐Hb in the lateral channels. These findings suggest that the higher the age of onset of depression, and the more prominent the vascular lesions, the greater the attenuation in lateral frontal and temporal activation, as indicated by NIRS. Conclusions: Multichannel NIRS is useful for demonstrating attenuated functional activation in the left lateral prefrontal and temporal areas in LOD and, thus, for differentiating between LOD and EOD. The NIRS findings observed may have useful clinical implications for treatment‐resistant LOD.  相似文献   
80.
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