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《Best Practice & Research: Clinical Rheumatology》2022,36(3):101759
In subjects older than 50 years, the presence of clinical risk factors (CRFs) for fractures or a recent fracture is the cornerstone for case finding. In patients who are clinically at high short- and long-term risk of fractures (those with a recent clinical fracture or with multiple CRFs), further assessment with bone mineral density (BMD) measurement using dual-energy absorptiometry (DXA), imaging of the spine, fall risk evaluation and laboratory examination contributes to treatment decisions according to the height and modifiability of fracture risk. Treatment is available with anti-resorptive and anabolic drugs, and from the start of treatment a lifelong strategy is needed to decide about continuous, intermittent, and sequential therapy. Implementation of guidelines requires further initiatives for improving case finding, public awareness about osteoporosis and national policies on reimbursement of assessment and therapy. 相似文献
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Anti-Oxidant,Anti-Hemolytic Effects of Crataegus aronia Leaves and Its Anti- Proliferative Effect Enhance Cisplatin Cytotoxicity in A549 Human Lung Cancer Cell Line 下载免费PDF全文
Islam OmairiFiras Kobeissy Salam Nasreddine 《Asian Pacific journal of cancer prevention》2020,21(10):2993-3003
Objective: For Arabian traditional medicine, Crataegus aronia syn. Azarolus (L) Bosc. ex DC (Rosaceae) is widely used to treat diabetes, sexual weakness, cardiovascular diseases and cancer. The anti-cancerous and anti-hemolysis effects of the hydroalcoholic extract of this plant have never been investigated before. The present study aims to evaluate the biological activities of the hydroalcoholic extract of Crataegus aronia leaves in combination with cisplatin, one of the most widely employed chemotherapeutics, on A549 human lung cancer cell line. Methods: The anti-oxidant and anti-proliferative activities of leaves, fruits, seeds of C. aronia were investigated by DPPH method and MTT assay; respectively. Cell migration activity was investigated by wound healing and by cell aggregation assays. The effect of C. aronia in inducing cell cycle arrest along with activating cell apoptosis was evaluated by flow cytometry and Western blot assays, respectively. Results: Our results showed that C. aronia leaves (C. aronia L.) had the highest anti-oxidant and anti-proliferative activities. The leaves extract was potent against hemolysis of the human erythrocytes and showed elevated decrease in migration by reducing wound healing migration and by increasing cell aggregation. Finally, C. aronia L. treatment exhibited apoptotic activity on A549 cells by the down-regulation of PARP-1, caspase-3 and Bcl-2 proteins and by increasing the percentage of A549 cells in sub G0 cell cycle. Moreover, the co-treatment of C. aronia L. and cisplatin remarkably sensitised A549 cells to cisplatin. Conclusion: The results suggested that C. aronia L. could be used as a potential treatment against human lung cancer exhibiting minimal side effects on human health. 相似文献
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《Dental materials》2020,36(3):413-419
ObjectiveA method proposed for determining the fracture toughness (FT) of dental materials involves a ‘roller’ wedging open a V-notch in a cylindrical specimen. There are a number of problems with the design of this test and its mechanical analysis, and thus with the validity of the results obtained, were it to be used. Firstly, friction is ignored in calculating the horizontal wedging force. Secondly, the test specimen does not make use of a pre-crack at the notch tip. The aim of this study was to evaluate the effects of these factors on the FT calculated.MethodsAn analytical solution for the mode-I stress intensity factor (KI) of the compact tension specimen, which bears some similarities, is taken to be applicable. The mechanics of the specimen has been reanalysed, with a finite-element study of the resultant stresses, and compared with the compact-tension test.ResultsThe assumed analytical solution can provide accurate estimates for KI for the V notched specimen. However, the apparent agreement is due to the fortuitous combination of an overestimated horizontal wedging force and an underestimated stress singularity at the crack tip. In any case, ignoring friction will lead to an overestimate of FT.SignificanceIt is concluded that the test as presented is invalid. 相似文献
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CT三维重建技术已经广泛应用于骨折诊断及其分型。基于CT三维重建的骨折地图绘制技术,通过绘制骨折模型来直观展现骨折线的形态学,包括骨折线的起止、走行、骨折面积等。骨折地图绘制技术为骨折诊断、骨折分型、治疗方案选择、手术内固定物设计、骨折好发部位统计、骨折标准化模型制定均提供了一个全新的方法。本文将回顾目前国内外包括对于肩胛骨骨折、胫骨远端骨折、尺骨冠状突骨折、胫骨平台骨折、桡骨小头骨折、股骨转子间外侧壁骨折、髋臼四边体骨折等骨折地图的研究进展,归纳总结了以上各个骨折模型的骨折好发部位及骨折地图绘制技术在骨折分型等方面的应用,并探讨骨折地图的临床应用前景及骨折地图绘制技术存在的问题等。 相似文献
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《Journal of Clinical Orthopaedics and Trauma》2020,11(2):298-301
Alagille Syndrome is a rare autosomal dominant genetic disorder, occur only 1:70,000 in population, and characterized by reduced interlobular bile ducts, and resultant nutritional deficiencies associated with the inability to absorb fat-soluble vitamins such as vitamin D. Patients are at risk for secondary osteoporosis, rickets/osteomalacia, and ultimately may result in fracture. The majority of patients suffer from chronic cholestasis, which can have a variety of adverse effects on bone metabolism. Hypothyroidism has been described in some Alagille Syndrome patients, and eventually delayed puberty can occur. Two until fourteen percents of patients of Alagille syndrome will suffer from fractures, in which it primarily occurs in the lower limb long bones in the absence of significant trauma. This study aimed to present a rare case of pathological fracture of femur in Alagille syndrome patient and its management in our hospital.Six-year-old male with pain on his right thigh came to our ER after fell down while putting on his pants. He had been diagnosed with biliary atresia at the age of 3 months and underwent surgical bile duct reconstruction. In addition, he also suffered from congenital hypothyroidism and consequently, stunted growth. The pathological fracture of the femur was treated conservatively with hemispica cast. At 2 months follow up, there is already radiographic evidence of fracture healing occurred by secondary intention and callus formation.By ensuring adequate calcium and vitamin D intake, monitoring for vitamin D deficiency, monitoring for fragility fractures, and avoiding trauma-related accidents, a proper conservative treatment using hemispica cast could still always be considered for managing such diaphyseal fractures in Alagille syndrome, especially in relatively low-resource countries such as Indonesia. 相似文献
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如何对股骨转子间骨折、尤其是头颈骨块进行有效固定,进而稳定并支撑骨质疏松的骨折端,已成为当今创伤骨科研究的热点之一。为了减少固定失败率,临床上除了提高内固定的设计,应用骨增强材料提高固定的效果是另一个富有前景的研究领域。因此,本文围绕骨水泥增强材料的研究历史、材料特点、目前其生物力学和临床应用研究等方面进行综述,以提高对骨生物增强材料进行内固定的原理、手术技术和应用范围的认识,进而为其临床应用的选择提供帮助。 相似文献
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