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991.
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993.
Temperature gradient was first used to identify the methylation status of the DNA sequence over 10 years ago; however, the initially published protocol was shown to have poor analytical sensitivity. Recent developments in the field of DNA melting technologies, combined with the identification of procedures to overcome the sensitivity issues in the PCR-based methylation detection applications, led to the development of the methylation-sensitive high-resolution melting (MS-HRM) protocol. This protocol allows for highly sensitive detection of methylation levels in a labor- and cost-efficient fashion. Moreover, it enables investigation of methylation status of imprinted loci as well as identification of heterogeneous methylation. The MS-HRM technology is being increasingly applied in research laboratories and has a potential for future application in diagnostic settings. The focus of this article is to describe the development of the HRM technology for methylation analyses and evaluate the diagnostic applicability of the MS-HRM technology.  相似文献   
994.
During platelet activation over 30 growth factors are released from their alpha granules. By concentrating platelets, higher levels of growth factors are obtained and can be used to stimulate the healing processes. Moreover, during blood centrifugation, huge numbers of leukocytes and thrombocytes can be obtained to form leukocyte and platelet-rich plasma (L-PRP). After platelet degranulation the active gelatinous matrix called leukocyte and platelet-rich gel (L-PRG) is formed. In the present clinical study, we report the influence of PLRG and freeze-dried allografts on healing of large femoral bone cysts. Each of 6 participants was followed on a regular basis with clinical examinations, roentgenograms and dual-energy X-ray absorptiometry (DXA) examinations. Our four-year follow up clinical study using allografts and PLRG in the treatment of large cystic lesions of the proximal femur showed that mixing these substances is not efficient and it might induce unknown local reactions between them causing complete bone graft destruction. Further studies are necessary to fully understand the mechanisms of the local activity of L-PRP gel.  相似文献   
995.
Pain is one of the most frequent and most distressing symptoms in the course of cancer. The management of pain in cancer patients is based on the concept of the World Health Organization (WHO) analgesic ladder and was recently updated with the EAPC (European Association for Palliative Care) recommendations. Cancer pain may be relieved effectively with opioids administered alone or in combination with adjuvant analgesics. Corticosteroids are commonly used adjuvant analgesics and play an important role in neuropathic and bone pain treatment. However, in spite of the common use of corticosteroids, there is limited scientific evidence demonstrating their efficacy in cancer patients with pain. The use of corticosteroids in spinal cord compression, superior vena cava obstruction, raised intracranial pressure, and bowel obstruction is better established than in other nonspecific indications. This review aims to present the role of steroids in pain and management of other symptoms in cancer patients according to the available data, and discusses practical aspects of steroid use.  相似文献   
996.
Atrial fibrillation (AF) is associated with a five-fold increased risk for stroke due to cardioembolic events. Most strokes in patients with AF arise from thrombus formation in the left atrial appendage (LAA). Oral anticoagulation is a standard treatment of AF patients with high risk of stroke. However, the main drawbacks of oral anticoagulation are high risk of major bleeding and imperfect effectiveness dependent on a very narrow therapeutic range. In this article, based on two case reports, we describe a method of percutaneous closure of the LAA. We discuss indications, describe the procedure and mention possible complications. LAA closure seems to be a promising tool to prevent AF-related strokes in a selected group of patients.  相似文献   
997.
Background and purposeThe Montreal Cognitive Assessment (MoCA) test is a brief cognitive screening tool with high sensitivity and specificity for detecting mild cognitive impairment (MCI). The aim of this study was to evaluate the usefulness of MoCA and compare it with the Mini-Mental State Examination (MMSE) in the early detection of cognitive decline in MCI.Material and methodsA group of 115 subjects (36 meeting DSM-IV criteria for Alzheimer disease (AD) [Clinical Dementia Rating (CDR) = 1], 42 meeting Petersen's criteria for MCI [CDR = 0.5], and 37 cognitively intact controls [CDR = 0]) was recruited for the study in the university-based Alzheimer out-patient clinic. All participants underwent general medical, neurological, and psychiatric examinations. The MoCA, the MMSE, CDR and the short (15-item) version of the Geriatric Depression Scale were also applied.ResultsBoth MCI and AD groups exhibited impaired performance on MoCA compared to controls. Polish versions of the MMSE and MoCA tests were comparable in discriminating mild dementia from both MCI and control groups. The Polish version of the MoCA test performed marginally better than MMSE in discriminating MCI from controls. We propose to use the MoCA test to screen for MCI using an optimal cut-off score of 24 and to screen for dementia using a cut-off score of 19.ConclusionsThe Polish version of the MoCA seems effective in the detection of deteriorated cognitive performance and appropriate for differentiating impaired from preserved cognitive function in a Polish population.  相似文献   
998.
999.
CONCLUSIONS: The determination of cyclin A expression might be helpful in the identification of laryngeal squamous cell cancer (LSCC) patients with increased risk of metastases. The results suggest that cyclin A may be a more informative marker for cell proliferation than Ki-67. Abnormalities of cyclin E and cyclin A may play an important role in LSCC development and progression; however, the expression of cyclin E does not seem to have prognostic significance. OBJECTIVE: The aim of the study was to elucidate a possible association between cyclin E and cyclin A expression and clinicopathologic factors and their potential role as prognostic markers for patients with laryngeal epithelial lesions. MATERIALS AND METHODS: Expression of cyclins E and A, and Ki-67 was examined immunohistochemically in a formalin-fixed, paraffin-embedded series of 46 LSCC; 23 epithelial dysplasias (ED); and 21 normal mucosae (NM). RESULTS: The mean labeling indices (LIs) for cyclin E in LSCC, ED, and NM were 10.6%, 4.9%, and 0%, and for cyclin A 27.2%, 17.5%, and 7%, respectively. In LSCC, a statistically significant correlation was found between enhanced cyclin A expression and a higher incidence of locoregional lymph node metastasis (p0.01). The enhanced expression of cyclin A was linked with cell proliferation in LSCC, ED, and NM. No association was observed between cyclin E and A and other clinicopathologic parameters or applied treatments. The prognostic significance of cyclin E, cyclin A, and Ki-67 in determining overall survival time showed no statistically significant differences.  相似文献   
1000.
The BCR-ABL1 oncoprotein transforms pluripotent HSCs and initiates chronic myeloid leukemia (CML). Patients with early phase (also known as chronic phase [CP]) disease usually respond to treatment with ABL tyrosine kinase inhibitors (TKIs), although some patients who respond initially later become resistant. In most patients, TKIs reduce the leukemia cell load substantially, but the cells from which the leukemia cells are derived during CP (so-called leukemia stem cells [LSCs]) are intrinsically insensitive to TKIs and survive long term. LSCs or their progeny can acquire additional genetic and/or epigenetic changes that cause the leukemia to transform from CP to a more advanced phase, which has been subclassified as either accelerated phase or blastic phase disease. The latter responds poorly to treatment and is usually fatal. Here, we discuss what is known about the molecular mechanisms leading to blastic transformation of CML and propose some novel therapeutic approaches.  相似文献   
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