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INTRODUCTION: Osteoporosis is a major health problem in the elderly population particularly in postmenopausal women. Various techniques are currently available for detection and diagnosis of osteoporosis in humans, but not all of these can be used for evaluation of osteoporosis in animals. We assessed the feasibility and applicability of a spiral CT-scanning technique for use in evaluating bone loss in rats. In addition, we also tested the applicability of dispersive quantitative X-ray analysis (QXRA) coupled with scanning electron microscopy (SEM), and impact test to detect bone mineral content and biomechanical strength, respectively. METHODS: Twenty female Sprague Dawley rats were randomly assigned to sham operated or bilaterally ovariectomized groups and fed with a calcium-deficient diet for 16 weeks. Femurs and tibias were collected at termination. Using a spiral CT-scanner various cortical bone morphometric indices were measured in femurs. SEM-QXRA was used to quantify the calcium to phosphorus ratio (Ca:P) in regions of high bone turnover both in sham and CD-OVX rats. Tibias were subjected to the impact test for evaluation of biomechanical strength. RESULTS: Compared to sham operated rats, the CD-OVX animals had decreased combined cortical thickness (CCT), cortical area (CA), cortical area/periosteal area and radial density (RD), with increased medullary width and cross sectional areas as determined by CT-Scanning technique. SEM-QXR analysis indicates a decreased Ca:P ratio in the metaphyseal regions of distal femurs in CD-OVX rats when compared to sham-operated rats. The results of the impact test demonstrate lower threshold energy in tibias of CD-OVX rats compared to sham operated rats. DISCUSSION: The ability of these techniques to distinguish the bone characteristics of sham-operated rats from CD-OVX rats provides a methodological opportunity to assess osteoporosis in small animals like rats.  相似文献   
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Horne  MK d; Rosse  WF; Flickinger  EG; Saltzman  HA 《Blood》1975,45(3):365-375
The "early-labeled" peak (ELP) of 14CO excretion following injection of glycine-2-14C was used to study erythropoiesis in a patient with sideroblastic anemia and in four subjects with myeloproliferative disorders. The ELP was greatly enlarged in all patients, as compared with a normal volunteer. The contour of the peaks from the hematologically abnormal subjects suggested the presence of increased erythroid heme degradation. In the patient with sideroblastic anemia, all hours of the early peak were significantly reduced after transfusion. This was interpreted to mean that even the earliest or "nonerythroid" phase of the peak is influenced by erythropoietic activity, at least under conditions of erythropoietic stress.  相似文献   
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One-step SYBR Green I-based real-time RT-PCR assay for rapid detection as well as quantitation of Japanese encephalitis virus (JEV) in acute-phase patient CSF samples by targeting the NS3 gene was developed. The assay developed in this study was found to be more sensitive as compared to conventional RT-PCR. The specificity of the reported assay system was established through melting curve analysis as well as by cross-reactivity studies with related members of Flavivirus. The applicability of Real-time PCR assay for clinical diagnosis was validated with 32 suspected acute-phase CSF samples of Gorakhpur epidemic, India, 2005. The improved sensitivity of real-time RT-PCR was reflected by picking up 10 additional samples with low copy number of template in comparison to conventional RT-PCR. The quantitation of the viral load in acute-phase CSF samples was done using a standard curve obtained by plotting cycle threshold (C(t)) values versus copy numbers of the RNA template. This is the first report on the application of real-time RT-PCR for detection as well as quantitation of JEV from patient CSF samples. These findings demonstrate the potential clinical application of the reported assay as a sensitive diagnostic test for rapid and real-time detection and quantitation of JEV in acute-phase clinical samples.  相似文献   
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Microglandular adenosis (MGA) and atypical MGA (AMGA) are unusual lesions of the breast. They were once regarded as benign proliferative lesions and innocent bystanders. Several lines of evidence suggested that they could be neoplastic, clonal lesions and a non‐obligate precursor for triple‐negative breast cancers (TNBC). Recent work published in The Journal of Pathology by Guerini‐Rocco and colleagues provided further evidence regarding the precursor–product relationship between MGA/AMGA and TNBC. Using a massively parallel sequencing approach, they demonstrated that MGA/AMGA, particularly those associated with TNBC, could be clonal neoplastic lesions showing clonal non‐synonymous mutations, but none in pure MGA. Importantly, those alterations were observed in the associated TNBC. They were also able to identify recurrent alterations in TP53 in those MGA/AMGA cases as well as their associated TNBC. The findings, in conjunction with others, underscore the significance for MGA in clinical diagnosis. The potential of a benign lesion to progress into an aggressive malignant tumour implies that modification of the current management approach may be necessary. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.  相似文献   
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