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61.
BACKGROUND: Hemodialysis (HD) patients are at increased risk for arterial intimal (AIC) and medial calcification (AMC). METHODS: In a cross-sectional study on 153 HD patients we evaluated the presence of AIC and AMC using plain radiography of the pelvis and the presence of atherosclerotic lesions using high-resolution B-mode ultrasonography of the common carotid arteries (CCA). RESULTS: The radiography of the pelvis confirmed the frequent presence of AIC (35.3%) and AMC (35.9%) in our HD patients. Arterial calcification was absent (non calcified-NC) in a minority of patients (28.8%). Patients with AIC had significantly higher prevalence of atherosclerotic plaques on CCA (78.6%) compared with both other groups and a higher number of documented atherosclerotic complications, such as cardiovascular (85.2%), cerebrovascular (33.3%) and peripheral arterial disease (38.9%) in comparison with the NC patients. According to the 1-year calculated data from patient records, there were no significant differences in the specific HD risks, such as the dose of prescribed calcium carbonate and vitamin D3, serum levels of calcium, phosphate, calcium-phosphate product and intact parathyroid hormone. All four bone metabolism markers within the range proposed by K/DOQI guidelines were achieved in 9.3%, 14.5% and 20.4% in the AIC, AMC and NC group, respectively. CONCLUSIONS: Patients with AIC and AMC are frequently found in the HD population. Screening for arterial calcifications in chronic kidney disease patients is suggested even in the early pre-dialysis period. The highest proportion of patients within the guidelines proposed range for bone and mineral metabolism markers was observed in the NC group. A longer period of data analysis is required in order to evaluate the possible role of some traditional and HD-specific risk factors for the development of arterial calcifications. The achievement of the K/DOQI guidelines is an important issue in the prevention of those conditions.  相似文献   
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Any endoscopic diagnostic procedure that is capable of giving exact information on laryngeal lesions without damaging the tissue has essential advantages over standard biopsy. Tissue autofluorescence is defined as a natural ability of tissue to fluoresce when exposed to a certain light wavelength. This feature is a consequence of the presence of fluorophores in the tissues, which are activated by a narrow wavelength range. However, due to their biochemical and biophysical characteristics, laryngeal precancerosis and cancer do not fluoresce when exposed to blue light. In the present study, we used Pentax’s System of Autofluorescent Endoscopy (SAFE 1000) to detect autofluorescence disturbances from laryngeal mucosa. Diagnostic parameters (sensitivity and specificity) of the microlaryngoscopy (MLS) and SAFE 1000 in the diagnosis of laryngeal precancerosis and carcinoma were compared and discussed. We have found that SAFE had a better sensitivity with regard to mentioned laryngeal pathology, but MLS had better specificity than SAFE. The overall diagnostic sensitivity in the diagnostics of laryngeal atypical hyperplasia and cancer with SAFE was 89%, as opposed to 73% with MLS. Diagnostic specificity of SAFE for all cases of laryngeal carcinomas and atypical hyperplasia was 78%. The specificity of MLS in diagnostics of laryngeal carcinomas cases was 98%, while that for cases of atypical hyperplasia was 100%. Many other conditions that have impact on autofluorescent features of laryngeal mucosa were also discussed.  相似文献   
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The aim of the paper was to examine the correlation between the total risk of cardiovascular events, determined by the SCORE (Systematic Coronary Risk Evaluation) system, and bone density in postmenopausal women. Examinees and method: The research involved 300 postmenopausal women. On the basis of bone density measurements, the participants were divided into three groups: group I — 84 examinees had osteoporosis, group II — 115 examinees had osteopenia, and group III — 101 examinees had normal bone mineral density (BMD). Results: Participants with high SCORE risk were statistically significantly older compared to low-risk women (60±3 vs. 55±5; p<0.001). They had significantly lower BMD and T scores (?1.09±0.94 vs. ?2.86±0.63; p<0.001). Elevation of the SCORE risk by 1% caused a BMD decrease of 0.033 g/cm2(0.029 to 0.036 gr/cm2). Multivariate logistic regression analysis showed that the following factors caused a significant increase in the risk of decreasing BMD: every year of life by 20%, menopause duration by 26%, increase in systolic blood pressure (BP) by 1 mm Hg by 7%, increase in SCORE risk by 1% by 5.31 times, physical inactivity by 5.96 times, and osteoporosis in the family history by 3.91 times. Conclusion: Postmenopausal women who are at high risk for cardiovascular diseases have a lower BMD than those who are not at high risk for cardiovascular diseases.  相似文献   
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Cognitive dysfunction is one of the hallmarks of Huntington's disease (HD) and may precede the onset of motor symptoms. The Montreal Cognitive Assessment (MoCA), a brief cognitive screening instrument with high specificity and sensitivity for detecting early cognitive impairments, has not been studied in the HD population. In this study, we compare the MoCA with the mini‐mental state examination (MMSE) as a screening tool for cognitive dysfunction among 53 patients with HD. The mean MMSE score was 26 ± 2.4, and mean MoCA score was 21 ± 4.4. Twenty‐one patients (81%) of those who scored ≥26 on the MMSE had the MoCA score <26. Thirty‐two patients (78%) of those who scored ≥24 on the MMSE had the MoCA score <24. The MoCA may be a more sensitive screening tool for cognitive impairments in HD relative to the MMSE. © 2010 Movement Disorder Society  相似文献   
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Measurement of serum thyroglobulin (Tg) is a highly specific test in the management of patients with differentiated thyroid cancer (DTC) after surgical treatment. The aim of our study was to evaluate and compare Tg levels in these patients found by radioimmunoassay (RIA) and immunoradiometric assay (IRMA) and to assess the influence of Tg antibodies (TgAbs) on the values obtained for Tg concentration. Both Tg and TgAb were determined postoperatively in the serum of 71 DTC patients using RIA Tg‐PEG (INEP) and Tg IRMA (CIS) for Tg, together with TgAb (CIS) for circulating endogenous anti‐TgAbs. The obtained concentrations were evaluated statistically. We found a significant difference of Tg concentrations between paired samples from the IRMA and RIA, although the intermethod comparison yielded satisfactory concordance of the twoassays (Spearman correlation coefficient ?0.792). Positive TgAb was found in 28.2% of the serum samples analyzed. Spearman rank correlation analysis revealed a significant negative relationship between serum TgAb and Tg level measured by IRMA (P=0.02), but not by RIA (P=0.417). On the other hand, our clinical data revealed that 1/18 and 3/18 patients with proven lymph node metastasis had Tg values below the detection limit by RIA and IRMA assay, respectively. Their sera were TgAb positive. We concluded that RIA was less prone to influence of TgAb than IRMA. As the presence of TgAbs may interfere in Tg measurement irrespective of the method selected for determination, this should be considered during the clinical management of these patients. J. Clin. Lab. Anal. 23:341–346, 2009. © 2009 Wiley‐Liss, Inc.  相似文献   
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Secretory vesicle swelling is central to cell secretion, but the underlying mechanism of vesicle swelling, particularly synaptic vesicles, is not completely understood. The Gαi3‐PLA2‐mediated involvement of water channel AQP‐1 in the regulation of secretory vesicle swelling in exocrine pancreas and the Gαo‐mediated AQP‐6 involvement in synaptic vesicle swelling in neurons have previously been reported. Furthermore, the role of vH+‐ATPase in neurotransmitter transport into synaptic vesicles has also been shown. Using nanometer‐scale precision measurements of isolated synaptic vesicles, the present study reports for the first time the involvement of vH+‐ATPase in GTP‐Gαo‐mediated synaptic vesicle swelling. Results from this study demonstrate that the GTP‐Gαo‐mediated vesicle swelling is vH+‐ATPase dependent and pH sensitive. Zeta potential measurements of isolated synaptic vesicles further demonstrate a bafilomycin‐sensitive vesicle acidification, following the GTP‐Gαo‐induced swelling stimulus. Water channels are bidirectional and the vH+‐ATPase inhibitor bafilomycin decreases both the volume of isolated synaptic vesicles and GTP‐mastoparan stimulated swelling, suggesting that vH+‐ATPase is upstream of AQP‐6, in the pathway leading from Gαo‐stimulated swelling of synaptic vesicles. Vesicle acidification is therefore a prerequisite for AQP‐6‐mediated gating of water into synaptic vesicles. © 2009 Wiley‐Liss, Inc.  相似文献   
70.
The presence of multiple dermatofibromas is rare and is defined as more than 15 lesions. Multiple clustered dermatofibroma (MCDF) is a distinct entity with only 12 reported cases in the literature. MCDF occurs in healthy individuals of both sexes in the first to third decades on the lower half of the body and portends an excellent prognosis. On histology, MCDF is consistent with benign dermatofibromas. We report a 31‐year‐old healthy Hispanic woman with a 14‐year history of slowly progressive MCDF located on her right hip initially misdiagnosed as dermatofibrosarcoma protuberans. We believe this case represents the 13th report of MCDF in the literature and the second from North America. Gershtenson PC, Krunic AL, Chen HM. Multiple clustered dermatofibroma: case report and review of the literature.  相似文献   
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