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41.
42.
Angiosarcoma is a rare, highly malignant tumor arising from endothelial cells of small blood vessels. They usually occur in the skin, deep soft tissues, breast and liver. Pleural angiosarcomas are extremely rare and are restricted to case reports in medical literature. It is very difficult to distinguish them from malignant mesotheliomas on clinical, radiological and even histopathological features. Immunohistochemistry is valuable in making the diagnosis, showing negative reactivity for mesothelial markers and positivity for vascular markers. Prognosis is generally dismal except in occasional cases where the disease is localized and amenable for surgical resection. We report a 55-year-old man who presented to us with chest pain, cough and hemoptysis and was diagnosed to have a pleural angiosarcoma.  相似文献   
43.

Objectives

To compare three instruments for their ability to quantify enamel loss after acid erosion.

Methods

6 randomized parallel groups of bovine enamel samples were subjected to citric acid (higher acidity) or orange juice (lower acidity) erosion and remineralisation in a cycling model. Two protected shoulders were created on each of the samples using tape, to serve as reference for analysis. The time of exposure to each acid was varied, along with presence or absence of agitation. After treatment, samples were measured on 3 instruments capable of measuring step height: a contact profilometer (CP); a non-contact profilometer (NCP); and a confocal laser scanning microscope (CLSM) by three different examiners. Additionally, 3D (volume) step height was also measured using the CLSM.

Results

Increasing acid concentration and exposure time resulted in greater erosion, as did agitation of samples while in acid solution. All instruments/methods identified the same statistically significant (p < 0.05) pair-wise differences between the treatments groups. Further, all four methods exhibited strong agreement (Intra-class correlation ≥ 0.96) in erosion level and were highly correlated, with correlations of 0.99 or higher in all cases.

Significance

All instruments/methods used in this study produced very similar conclusions with regard to ranking of enamel loss, with data showing very high agreement between instruments. All instruments were found to be equally suited to the measurement of enamel erosion.  相似文献   
44.
Here we report the first multi-center clinical trial in Alzheimer's disease (AD) using fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) measures of brain glucose metabolism as the primary outcome. We contrasted effects of 12 months treatment with the PPARγ agonist Rosiglitazone XR versus placebo in 80 mild to moderate AD patients. Secondary objectives included testing for reduction in the progression of brain atrophy and improvement in cognition. Active treatment was associated with a sustained but not statistically significant trend from the first month for higher mean values in Kiindex and CMRgluindex, novel quantitative indices related to the combined forward rate constant for [18F]FDG uptake and to the rate of cerebral glucose utilization, respectively. However, neither these nor another analytical approach recently validated using data from the Alzheimer's Disease Neuroimaging Initiative indicated that active treatment decreased the progression of decline in brain glucose metabolism. Rates of brain atrophy were similar between active and placebo groups and measures of cognition also did not suggest clear group differences. Our study demonstrates the feasibility of using [18F]FDG-PET as part of a multi-center therapeutics trial. It suggests that Rosiglitazone is associated with an early increase in whole brain glucose metabolism, but not with any biological or clinical evidence for slowing progression over a 1 year follow up in the symptomatic stages of AD.  相似文献   
45.
46.
Posttranslational modifications, particularly proteolysis, may play a significant role in the regulation of insulin-like growth factor (IGF)-binding protein-3 (IGFBP-3) physiology, and thus, measurement of modified variants of IGFBP-3 and/or their combination ratios may have important research and diagnostic relevance. Based on evaluation of a panel of monoclonal and polyclonal IGFBP-3 antibodies, we constructed three new enzyme-linked immunosorbent assays (ELISAs) using a common capture and polyclonal (ELISA-3) or monoclonal (ELISA-1 and -2) detection antibodies and evaluated them in a two-step colorimetric procedure. Evaluation of ELISA-1-3 demonstrated detection limit, dynamic range, overall precision, and recovery of the added IGFBP-3 to be generally less than 0.04 microg/L, 2-100 microg/L, less than 10%, and 91-113%, respectively. IGF-I and -II, and IGFBP-1, -2, -4, -5, and -6 did not interfere. In normal adult sera (n = 26), seminal plasma (n = 14), pregnancy sera (n = 30), and amniotic fluid (n = 30), ELISA-1-3 detected significantly different IGFBP-3 levels (by up to 6-fold, on the average), whereas levels in seminal plasma determined by ELISA-1 were undetectable. Comparison of the values obtained vs. corresponding levels by an established method (Diagnostic Systems Laboratories, Inc., active IGFBP-3 ELISA) were similarly sample dependent and, on the average, varied by up to 19-fold. Only ELISA-3 compared well with the Diagnostic Systems Laboratories, Inc., IGFBP-3 ELISA when samples from normal adults were analyzed. The observed variability could not be totally explained by 50% lower reactivity of ELISA-1-3 for glycosylated IGFBP-3 vs. the nonglycosylated form, and changes in phosphorylation had no effect on immunoreactivity. Evaluation of IGFBP-3 after proteolysis by seminal plasma, plasmin, or thrombin suggested recognition of intact IGFBP-3 by ELISA-1, whereas ELISA-3 appeared to measure intact and proteolyzed IGFBP-3 (total IGFBP-3) with similar potency. In contrast, levels determined by ELISA-2 increased severalfold, indicating preferential recognition of IGFBP-3 fragments. We propose that immunoassay capable of differential determination of IGFBP-3 variants may help better define the physiological importance and potential clinical value of IGFBP-3 measurements.  相似文献   
47.
Eleven patients with methylmalonic aciduria have been classified on the basis of detailed enzymology on cultured skin fibroblasts. Nine were classified as mutase deficiencies and were unresponsive to hydroxocobalamin in vivo or in vitro. One was classified as a Cbl A variant and was responsive to hydroxocobalamin therapy in vitro and in vivo. Patient 11 was classified as having deoxyadenosyltransferase deficiency (Cbl B). However, a clinical therapeutic trial of deoxyadenosylcobalamin resulted in no clinical or biochemical improvement. Further studies on the patient's cultured fibroblasts suggested that deoxyadenosylcobalamin fails to reach the mitochondria in an intact form. These studies show that detailed enzymologic classification is essential for the reliable evaluation of the response to therapeutic maneuvers; complementation studies alone may be inadequate to completely classify these patients. Therapy with deoxyadenosylcobalamin offers no advantages over the use of hydroxocobalamin in the treatment of patients with methylmalonic aciduria.  相似文献   
48.
Melanotic neuroectodermal tumor of infancy (MNTI) is a rare but well-documented lesion of neuroectodermal derivation. Maturation of the neural elements has been reported only occasionally. We report a case of MNTI of the maxilla showing maturation of neural elements to ganglionic cells. © Wiley-Liss, Inc.  相似文献   
49.
Autonomous aldosterone-secreting ovarian tumor   总被引:1,自引:0,他引:1  
The case of a young woman with primary aldosteronism originating extraadrenally--ovarian tumor--is reported. Clinically she presented with uncontrolled hypertension. Biochemical and hormonal profiles showed features of aldosteronism. The primary was found in the left ovary. Following excision of the tumor, aldosteronism regressed completely. Microscopically, the tumor was of the lipid cell type. Nine months after surgery she is asymptomatic and well. Review of the literature uncovered three previous reports of aldosterone-secreting ovarian tumors.  相似文献   
50.
The amniotic fluid composition of 74 pregnant women having abnormalities was compared with those of 70 normal pregnant women. Women having small for gestational age children showed a decrease of creatinine level and an increase of locithin to sphingomyelin (L/S) ratio. Anomic mothers had higher alkaline phosphatase. The calcium and creatinine were decreased and protein was increased in amniotic fluid of premature deliveries.  相似文献   
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