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181.
182.
汉族女性峰值骨密度和维生素D受体基因多态性及环境因素的相关性研究 总被引:1,自引:0,他引:1
目的 研究汉族女性峰值骨密度 (peakbonemineraldensity ,PBMD)与某些环境及遗传因素的关系。方法 选择健康的志愿者 1 5 9人 ,①通过饮食回顾法计算每日钙及蛋白入量 ;②通过 7d运动评估法计算运动强度 ;③使用DEXA骨密度仪 (HologicQDR 4 5 0 0 )测量志愿者腰椎和髋部骨密度 (BMD) ;④应用PCR -限制性片段长度多态性对维生素D受体 (VDR)基因进行多态性分析。结果 ①腰椎BMD结果参照日本人标准 ,低骨量或骨质疏松共有 35人 (2 2 % ) ,正常骨量者为 1 2 4人 (78% )。两组间体重及体重指数 (BMI)间有显著差异 ;②腰椎及髋部股骨颈BMD与体重呈正相关 ,髋部其余位点BMD值和BMI呈正相关 ;③VDR基因BsmI酶切多态性组间BMD无显著性差异。结论 本研究显示 :体重及或BMI是汉族女性PBMD重要保护因素之一。汉族女性PBMD和当前营养状态、运动强度、VDRBsmI酶切位点基因多态性未见有相关性 相似文献
183.
The greyhound is a fatigue fracture model of a short distance running athlete. Greyhounds have a high incidence of central
(navicular) tarsal bone (CTB) fractures, which are not associated with overt trauma. We wished to determine whether these
fractures occur because of accumulation of fatigue microdamage. We hypothesized that bone from racing dogs would show site-specific
microdamage accumulation, causing predisposition to structural failure. We performed a fractographic examination of failure
surfaces from fractured bones using scanning electron microscopy and assessed microcracking observed at the failure surface
using a visual analog scale. Branching arrays of microcracks were seen in failure surfaces of CTB and adjacent tarsal bones,
suggestive of compressive fatigue failure. Branching arrays of microcracks were particularly prevalent in remodeled trabecular
bone that had become compact. CTB fractures showed increased microdamage when compared with other in vivo fractures (adjacent tarsal bone and long bone fractures), and ex vivo tarsal fractures induced by monotonic loading (P < 0.02). It was concluded that greyhound racing and training often results in CTB structural failure, because of accumulation
and coalescence of branching arrays of fatigue microcracks, the formation of which appears to be predisposed to adapted bone.
Received: 12 November 1999 / Accepted: 10 March 2000 相似文献
184.
挑刺阳性反应点治疗腰椎骨质增生38例 总被引:1,自引:0,他引:1
试用三棱针挑刺腰部阳性反应点,治疗腰椎骨质增生38例,结果有效率100%,具有疗效好,费用低,疗程短,应用方便的特点. 相似文献
185.
目的 探讨自体微小颗粒骨复合碱性成纤维细胞生长因子(basic fibroblast growth factor,bFGF)治疗骨缺损的效果,为其临床应用提供实验依据。方法 将36只新西兰白兔双侧桡骨中上段制成骨缺损模型,分别植入自体微小颗粒骨、bFGF和自体微小颗粒骨与bFGF的复合物,同时设空白对照组,分别手术后第2、4、8周进行大体观察,X检查及组织学检查。术后第8周进行骨密度测定,比较修复骨缺损的疗效。结果 经大体观察、组织学及X线检查发现,术后第8周自体微小颗粒骨复合bFGF能更有效地修复节段性骨缺损,对照组无骨愈合迹象。术后第8周骨密度测定证明自体微小颗粒骨复合bFGF组骨密度值明显高于对照组。结论 自体微小颗粒骨复合bFGF组成骨速度快,成骨量多,修复骨缺损的能力明显强于自体微小颗粒骨组及单纯bFGF组。 相似文献
186.
Leigh D Mosel Evelyn Kat Frank Voyvodic 《Journal of Medical Imaging and Radiation Oncology》2004,48(2):267-271
Accessory ossicles of the foot are commonly mistaken for fractures. The accessory navicular is one of the most common accessory ossicles of the foot. There is a higher incidence in women and the finding might be bilateral in 50?90%. This entity is usually asymptomatic, although populations with medial foot pain have a higher prevalence. Three types of accessory navicular bone have been described. The type II accessory navicular is the most commonly symptomatic variant with localized chronic or acute on chronic medial foot pain and tenderness with associated inflammation of overlying soft tissues. Plain radiographic identification of the accessory navicular is insufficient to attribute symptomatology. Ultrasound allows for comparison with the asymptomatic side and localization of pain. Bone scintigraphy has a high sensitivity but positive findings lack specificity. Magnetic resonance imaging is of high diagnostic value for demonstrating both bone marrow and soft tissue oedema. 相似文献
187.
188.
A 49-year-old white female patient was referred to the ENT Department, Zentralkrankenhaus, Bremen, because of conductive hearing
loss. Widespread tumor formation was found in the left temporal bone and was identified by biopsy to be an osteoclastoma.
The tumor was extirpated surgically and reconstruction was performed. Periodic clinical follow-ups during a 36-month period
after surgery have included control computed tomographic scans and have shown no evidence for recurrent disease. The specific
pathology of the osteoclastoma is presented and different ways for treatment are discussed. 相似文献
189.
Kathleen M. Hanlon-Lundberg MD Russell S. Kirby PhD Sweeta Gandhi MD Fredrik F. Broekhuizen MD 《American journal of obstetrics and gynecology》1997,176(6):1149-1156
OBJECTIVE: This study aims to establish normal values for nucleated red blood cells in term singletons and factors associated with their elevation.STUDY DESIGN: Cord blood was prospectively collected from term singleton gestations from Feb. 1 to July 31, 1995. Umbilical vein white blood cells and nucleated red blood cells were counted and umbilical arterial pH was determined. Medical records provided maternal and neonatal information.RESULTS: Cord blood from 1112 cases was obtained and evaluated for nucleated red blood cells per 100 white blood cells. Nine outliers were censored (nucleated red blood cells per 100 white blood cells = 126 to 830); five cases were excluded because of missing data. The mean value of nucleated red blood cells per 100 white blood cells was 8.55, the SD was 10.27, and the range was 0 to 89. The value did not vary by maternal tobacco or drug use, anemia, fetal presentation, or mode of delivery. Both maternal diabetes and meconium were associated with elevated values, p < 0.01. Apgar scores and cord pHs showed trends toward inverse proportionality to the number of nucleated red blood cells per 100 white blood cells.CONCLUSION: The mean number of nucleated red blood cells per 100 white blood cells was 8.55, with a wide range and SD. Elevated values may be associated with markers of intrauterine hypoxia such as meconium, lower Apgar scores, and lower pH values. (Am J Obstet Gynecol 1997;176:1149-56.) 相似文献
190.
A review is presented of the recent advances in: (i) clinical features, (ii) biochemistry and molecular biology of alkaline phosphatase, (iii) genetic defect in hypophosphatasia, and (iv) prenatal diagnosis. Despite the recent progress, the pathogenesis of hypophosphatasia is far from being elucidated. More clinical cases and further characterization of the alkaline phosphatase gene mutations are needed for better understanding of the clinical spectrum of the entity. 相似文献