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51.
1. The effect of inflammation induced by lipopolysaccharide (LPS) injection on plasma follistatin (FS) concentrations was investigated. 2. Plasma FS and tumour necrosis factor-α concentrations increase following LPS administration in ewes. 3. The rise in FS is similar, but more sustained, to that previously observed after surgery. 4. These results indicate a possible functional link between FS, inflammation and the acute-phase response.  相似文献   
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53.
目的探讨抗感染重组合异种骨(anti-infective reconstituted bone xenograft,ARBX)对犬污染性桡骨缺损的一期植骨修复的效果. 方法在重组合异种骨(reconstituted bone xenograft,RBX)基础上,结合抗生素局部缓释技术,制备具有较强抗感染能力和较高成骨作用的ARBX.取成年杂种犬8只,于双侧桡骨中上段制成15 mm节段性骨缺损,在缺损处注入5×106 CFU/ml金黄色葡萄球菌1 ml,静置15分钟后,于双侧缺损区分别植入ARBX、RBX,并用钢板固定.术后6个月对存活的6只犬进行取材,通过解剖学、X线片、组织学及细菌学检查,比较ARBX和RBX一期植骨修复犬污染性桡骨缺损的效果. 结果术后6个月,ARBX侧有5只完全修复,1只中央部3 mm缺损未修复,均无骨髓炎表现,标本细菌培养均为阴性.RBX侧有1只部分修复,5只未能修复,残留8~13 mm缺损,均有明显骨髓炎表现,标本细菌培养均为阳性. 结论 ARBX具有较高成骨活性和较强的抗菌能力,能够一期植骨修复细菌污染性骨缺损.  相似文献   
54.
目的:研究钕激光照射对大鼠肿瘤生长的抑制作用.方法:采用钕激光在实验组荷瘤大鼠的肿瘤区及其肿瘤区周围进行照射,并观察抑制肿瘤的效果.结果:实验组大鼠肿瘤体的生长速度明显慢于对照组大鼠肿瘤体的生长速度.结论:用钕激光照射对抑制癌肿瘤的生长速度有明显的作用.  相似文献   
55.
刘忠  杨光  郑建波  余勤  陈兆年 《中华实验外科杂志》2004,26(1):929-930,插图7-4
Objective To investigate the effectiveness and mechanism of transplantation of autol-ogous bone marrow in treating femoral head necrosis. Methods Sixty New Zealand rabbits were randomly divided into groups A,B,and C after establishment of the models of femoral head necrosis. The left femoral head served as the control one,and the right as the experimental group. The mitoxantrone (0.1 mg/kg) with the help of DSA was injected into the femoral head of group A. One ml autologous bone marrow was injected into the femoral head of group B. In group C,mitoxantrone (0. 1 mg/kg) was injected,and 72 h later,1 ml autologous bone marrow was injected. Four months later,all rabbits were killed,and the femoral heads were removed and observed histologically and electron microscopically. Results The number of necrotic osteoclasts in groups A and B showed no significant difference ( P > 0.05 ), ande in group C, the number of necrotic femoral heads at the left and fight sides was 40. 60±4.11 and 21.33±2.16 respec-tively ( P < 0.05 ). At the experimental side of group C, the structure of majority bone cells was clear and intact,and necrosis was occasionally seen. Conclusion At the cellular level, local chemotherapy and au-tologous hematopoietic stem cell transplantation had certain effectiveness for aseptic necrosis of the femoral head.  相似文献   
56.
Dual-energy X-ray absorptiometry (DXA) and quantitative ultrasound (QUS) are the accepted modalities for the evaluation of fracture risk in the clinical setting. However, neither method provides a direct measurement of bone mechanics. In this study, we investigated a prototype device, known as a mechanical response tissue analyzer (MRTA), which provides direct mechanical measurements of mechanical properties of bone. A total of 56 healthy volunteers (20 men and 36 women) between the ages of 18 and 83 were recruited. The MRTA was used to measure the cross-sectional bending stiffness (EI) of the ulna bone. Axial speed of sound (SOS) at the ulna bone was determined by QUS; bone mineral content (BMC) and bone mineral density (BMD) were determined by DXA. Correlations, regression analysis, and analyses of variance (ANOVAs) were used to compare the three modalities. These analyses revealed that although there are strong linear relationships among the data collected by the various technologies, the bone properties reflected by MRTA are not fully explained by DXA and QUS. We conclude that the total information conveyed by MRTA measurements is unique. Further research is needed to delineate the different qualities of bone strength that are captured by MRTA, but not by DXA or QUS.  相似文献   
57.
Digital volume tomography (DVT) is an extension of panoramic tomography. With this diagnostic technique, characterized by high resolution, a narrow section width (0.125 mm) and three-dimensional display, small pathological processes can be well visualized. Twenty-five patients with the history of a progressive hearing loss were examined with DVT (Accu-I-tomo, Morita, Japan). The results were compared with pre- and intraoperative findings to evaluate the diagnostic value of DVT in cases of erosion of the ossicular chain. With high resolution and artifact-free demonstration of the middle ear and the ossicular chain, it was possible to define its continuity preoperatively by DVT in all 25 cases. An intact ossicular chain was found by DVT in 13 cases and was later confirmed by surgery. The predicted erosion of the ossicles was verified in 12 patients, and a tympanoplasty type III was performed. Digital volume tomography is an excellent technique to examine the middle ear cleft and inner ear, and expands the application of diagnostic possibilities in the lateral skull base. Therefore, improvement in preoperative diagnosis is achieved along with more accurate planning of the surgical procedure. Digital volume tomography delivers a small radiation dose with a high resolution and a low purchase price for the equipment.  相似文献   
58.
In 7 patients (5 girls, 2 boys) with the EMG or Wiedemann-Beckwith syndrome, statural growth, bone age (BA), weight and pubertal development were studied longitudinally. Height was above the 90th percentile (%) for chronological age (CA) after age 2 years, reaching an average of 2.5 SD above the mean at or after puberty. Adult or attained height also exceeded significantly (P<0.015) parental (genetic) target height by 13.2 cm on the average. In one girl, adult height prognosis (190 cm) could be reduced to an adult height of 183 cm by high-dose estrogen treatment. In most children, growth velocity remained above the 90th % up to 4–6 years of age and normalized thereafter. In all patients studied, bone age was markedly advanced and particularly so during the first 4 years after birth. Weight was above the 90th–97th % during infancy and early childhood and remained there, appropriate or slightly subnormal for height, until adulthood, except for 3 girls who reached and maintained the 50th % during or after puberty. Spontaneous pubertal development occurred within normal limits for CA and around the 50th % for BA. Except for the marked bone age acceleration, the reason for the increased statural growth and adult height in patients with the EMG syndrome is still unknown.  相似文献   
59.
Radiation-induced bone tumors in beagle dogs exposed to 90Sr have been evaluated in terms of their incidence, time of appearance, occurrence as multiple tumors, anatomic distribution, and the influence of sex on their development. Among dogs fed 90Sr during skeletal development, the incidence of bone tumors was dose dependent. Tumors thus appeared in 10 of 19 dogs receiving average skeletal doses of 130 Gy, 15 of 60 receiving 97 Gy, 5 of 61 receiving 61 Gy, 2 of 65 receiving 26 Gy, and 1 of 40 receiving 1.3 Gy. No tumors appeared among 66 dogs who received 8 Gy, 78 who received 0.3 Gy, and 80 non-irradiated controls, all of which have been observed for life. Among dogs given a single intravenous injection of 90Sr in early adulthood, tumor production was somewhat higher than among 90Sr-fed dogs at the same radiation dose: bone tumors were present in 6 of 25 dogs who received 62 Gy and 1 of 20 dogs who received 7.5 Gy. Bone tumors appeared sooner and were more often multiple in animals receiving the higher doses. Long bones were the sites of most of the tumors appearing after the highest dose level. Bones of the head, particularly the mandible, were the predominant site of tumors in the next highest dose level group.  相似文献   
60.
骨髓间充质干细胞促进骨-肌腱结合部愈合的初步观察   总被引:3,自引:0,他引:3  
[目的]观察骨髓间充质干细胞对骨-肌腱结合部愈合的影响.[方法]采用骨髓穿刺、全骨髓培养法获取兔骨髓间充质干细胞.36只18周龄新西兰大白兔随机分为2组,实验组将骨髓间充质干细胞与Pluronic F-127载体材料结合后,植入兔髌骨部分切除模型,对照组只进行手术,不植入细胞.在术后6、12、18周进行X线片、大体和组织学观察评估.[结果]X线片显示术后6、12、18周实验组骨-肌腱结合部新生骨面积显著大于对照组(P<0.01).大体观察可见实验组骨-腱结合部愈合较早.HE染色显示实验组术后6周有大量的纤维母细胞和类软骨细胞增生,并可见新骨形成;12周,髌腱与松质骨接触面软骨细胞移行带形成;18周,纤维软骨移行带排列更有序.Safranin 0染色显示实验组术后6周,基质染色较深,部分骨-腱结合处可见相对浓染区;12周,基质染色范围明显减少,沿类软骨细胞走行分布;18周,类软骨细胞集中的区域染色较12周有所减退.组织学检查显示实验组术后6、12、18周骨-腱结合部组织愈合明显,较对照组迅速.[结论]骨髓间充质干细胞可以促进骨-肌腱结合部细胞增生,促进其早期愈合.  相似文献   
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