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71.
During the normal healing process, an extraction site may lose significant bone volume, making implant placement problematic. Quantitative evaluations of the amount of bone maintained by socket preservation with various materials are limited. The objective of this study was to evaluate, both clinically and histologically, the extent of alveolar bone preservation by blood coagulum (BC) and the potential additional benefits of bone allograft material (AL) versus the state-of-the-art bovine bone mineral (BB), covered by a polyethylene glycol (PEG) barrier, in extraction socket grafting procedures. Adult patients (n = 32) with single-rooted teeth indicated for extraction were treated (45 sites). After atraumatic extraction, the sockets were filled with BC, AL, or BB and covered with a synthetic PEG barrier membrane. Changes in bone height and width were measured clinically and the amount of bone formed and residual graft particles were measured histologically after 6 months. Changes in ridge width at 6 months were ?1.5 mm for AL versus ?2.5 mm for BB and ?2.3 mm for BC. New bone formation amounted to 47.8%, 33.3%, and 28.2% at BC-, AL-, and BB-treated sites, respectively. Using AL with the PEG barrier preserved the ridge width at 6 months better than BB or BC and resulted in similar amounts of bone histologically to BB.  相似文献   
72.
中药黄芪对骨代谢的影响及相关基础研究进展   总被引:1,自引:0,他引:1       下载免费PDF全文
黄芪(Astragali Radix)为豆科黄芪属植物蒙古黄芪或膜荚黄芪的干燥根。始载于东汉末年的《神农本草经》,具有2000多年的药用史,在《本草纲目》中被列为上品,认为黄芪具有补气升阳、利水消肿、固表止汗、托疮生肌等功效。黄芪化学成分包括:葡聚糖、杂多糖等多糖成分;黄芪苷I、II、III和大豆皂苷等多种皂苷;天冬氨酸、丝氨酸等多种氨基酸;多种微量元素及叶酸、亚油酸、甾醇类等。目前对黄芪的化学成分研究多集中在黄芪多糖、黄芪皂苷或其有效单体成分。现代药理学研究表明,黄芪具抗肿瘤、免疫调节、心血管保护、保肝、改善神经系统功能、抗骨质疏松等生物活性,其中,黄芪对骨细胞代谢具有一定的调节作用。通过对近年来黄芪对骨代谢的影响及相关基础研究的文献汇总,发现黄芪甲苷等黄芪提取物及黄芪制剂大多通过对成骨细胞的促进及破骨细胞的抑制进行骨代谢的调节,亦有通过促进类骨素的分泌、激素水平的调节进行调控,本文综述了黄芪甲苷等黄芪提取物及黄芪制剂对骨代谢的基础、动物模型及临床3个方面近十年的研究内容进行综述,为研究中药黄芪对骨细胞代谢影响提供些许帮助并为防治骨质疏松症提供思路与参考。  相似文献   
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《Primary care》2019,46(1):175-190
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75.
目的分析研究绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标的相关性。方法选取2013年10月至2017年05月于重庆医科大学附属第一医院内分泌内科住院的绝经后女性2型糖尿病患者385名。搜集其基本资料、骨代谢指标及骨密度等。根据T值将这些患者分为骨质疏松组(233例)、骨量减少组(101例)和骨量正常组(51例),比较三组间骨代谢指标的变化,并对骨密度(bone mineral density,BMD)与各项骨代谢指标进行相关性分析。结果 1型前胶原氨基末端前肽(Type I procollagen N-terminal propeptide,P1NP)、骨钙素(bone Gla protein,BGP)在骨质疏松组显著高于骨量减少组、骨量正常组(P0.05);随着骨密度的降低,1型胶原羧基端肽β特殊序列(β-Carboxyl terminal peptide,β-CTX)逐渐升高,骨质疏松组、骨量减少组与骨量正常组相比较差异有统计学意义(P0.05);Spearman等级相关分析示P1NP、BGP、β-CTX与骨密度呈负相关,25(OH)D_3与骨密度呈现正相关。结论绝经后女性2型糖尿病伴骨质疏松症患者骨密度与骨代谢指标有一定的相关性,有助于预测骨折风险并及时抗骨质疏松治疗。  相似文献   
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矿化胶原材料是由胶原和羟基磷灰石组成的新型、有效的骨替代材料,多通过体外仿生学方法合成,模拟天然骨质的化学组成和结构,是一种严格的三维等级序列的多孔材料。因其具有良好的机械性能、生物相容性、骨传导性、骨诱导性和生物降解性等特性,在口腔医学中作为修复材料被广泛应用。文章就矿化胶原材料的性质、分类及其在口腔临床中的应用做一综述,以期为以后科学使用该种材料奠定基础。  相似文献   
78.
Periosteal new bone formation (PNBF) is a common finding in a large spectrum of diseases. In clinical practice, the morphology and location of periosteal lesions are frequently used to assist in the differential diagnosis of distinct bone conditions. Less commonly reported is the presence of PNBF on the ribs. This contrasts with the data retrieved from the study of skeletonized human remains that shows a high frequency of cases and a strong, albeit not specific, association between periosteal rib lesions and pulmonary conditions (e.g. tuberculosis). Despite that, an overall disagreement regarding the specificity and non‐specificity of periosteal reactions exists in the study of dry bone remains. The insufficient number of clinical models exploring the morphology and the pathophysiology of PNBF's and the lack of systematic studies of pathological samples with a known diagnosis are claimed as major reasons for the disagreements. This study aimed to describe and compare the macroscopic and the histomorphologic appearance of periosteal rib lesions and to discuss their usefulness as diagnostic indicators. To pursue this goal, an assemblage of 13 rib samples (males = 11, females = 2, mean age‐at‐death = 36.6 years old) was collected from the Luis Lopes Skeletal Collection (Museu Nacional de História Natural e da Ciência, Universidade de Lisboa, Portugal). The assemblage belongs to individuals who died from pulmonary‐TB (group 1), non‐TB pulmonary infections (group 2) and other conditions (group 3). Prior to sample preparation, the ribs were visually inspected and the PNBF described according to its thickness, the degree of cortical integration and the type of new bone formed (e.g. woven, lamellar or both). After sampling, each bone sample was prepared for histological analysis under plane and polarized light microscopy. Macroscopically, the results showed no differences in the new bone composition between cause‐of‐death groups. Only slight differences in the degree of cortical integration, which was most frequently classified as mild to high in the pulmonary‐TB group, were observed. Histologically, no distinguishing features were identified by pathological group. However, new bone microarchitectures were observed compatible with (1) acute, fast‐growing processes (e.g. spiculated reactions), (2) long‐standing processes with a rapid bone formation (e.g. appositional layering of bone) and/or (3) chronic, slow‐growing processes (e.g. layers of compact lamellae). To some extent, these distinct rates of disease progression resonate with the cause‐of‐death listed for some individuals. Despite the small sample size, the results of this investigation are in agreement with previous studies, according to which the macroscopic and histological appearance of periosteal formations are not specific for a particular pathological conditions. Nevertheless, the results support the conclusion that the morphology of periosteal lesions is a good biological indicator for inferring the rate of progression and duration of pathological processes. This study provides important reference data regarding the histomorphology of periosteal lesions that can be used for comparative purposes, as well as to narrow down the differential diagnosis in unidentified skeletal remains.  相似文献   
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80.
目的探讨全身振动训练联合正弦交变电磁场对去卵巢骨质疏松大鼠骨密度、骨代谢、骨生物力学性能的影响。方法将100只大鼠随机分为切除卵巢组和对照组,分别进行卵巢切除术和假手术,大鼠进行6周恢复,恢复后将造模成功的切除卵巢大鼠随机分为模型组(MO组)、全身振动训练组(W组)、正弦交变电磁场组(S组)、全身振动训练+正弦交变电磁场组(WS组),对照组列为假手术组(SO组),进行为期16周干预,干预结束后对大鼠进行骨密度、骨代谢、骨生物力学性质的检测。结果16周干预完成后,MO组、S组大鼠体质量显著高于SO组、W组、WS组大鼠(P0. 05); W组、WS组、SO组大鼠骨密度指标、血清雌二醇浓度指标明显高于大鼠MO组(P0. 05); SO组大鼠血清雌二醇浓度指标明显高于S组、W组、WS组(P0. 05); M组大鼠血清OC、ALP浓度明显高于SO组、W组、S组、WS组大鼠(P0. 05);尿液DPD/Cre、Ca/Cre、P/Cre浓度方面,M组大鼠明显高于SO组、W组、S组、WS组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组、W组、S组、WS组大鼠股骨断裂载荷组间无明显差异(P0. 05); SO组、W组、S组、WS组大鼠股骨弹性模量明显高于MO组大鼠(P0. 05)。SO组大鼠股骨弹性模量明显高于S组大鼠(P0. 05),但与W组、WS组大鼠没有明显差异(P0. 05)。L4椎体压缩试验,SO组、W组、S组、WS组大鼠股骨最大载荷和弹性模型明显高于MO组大鼠(P0. 05)。SO组大鼠高于S组、W组,差异有统计学意义(P0. 05),但与WS组大鼠没有明显差异(P0. 05)。结论全身振动训练、正弦交变电磁场、全身振动训练联合正弦交变电磁场3种干预方式施用于去卵巢骨质疏松大鼠均能提升骨密度、抑制骨吸收、平衡骨代谢、改善骨骼结构力学和材料力学性能。而全身振动训练联合正弦交变电磁场能的治疗效果优于单纯使用全身振动训练或正弦交变电磁场,在临床应用中有一定推广价值。  相似文献   
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