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101.
Wehavereported previouslythatligustrazinecouldpromotehematopoiesisthroughimprovingbonemarrowmicroenvironmentandenhancingadhesive  相似文献   
102.
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   
103.
Bone mineral density (BMD, g/cm2) was measured using dual-photon absorptiometry (DPA) in selected areas of the proximal tibia following uncemented PCA knee prosthesis. In nine patients with 14 alloplastic operations, measurements were taken at 3-6-month intervals for the first 3 1/2 years after operation. There was a significant increase in BMD of about 15% during the first 6 months after operation. The following year it remained increased, although not significantly, compared with the initial values, then gradually diminished. Increased bone density after arthroplasty may be explained mainly by stimulation of bone formation from weight bearing due to improved walking ability. Stress shielding of the proximal part of the supporting tibial bone did not seem to occur.  相似文献   
104.
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   
105.
富血小板血浆治疗下肢慢性难愈合伤口47例随访研究   总被引:4,自引:0,他引:4  
目的 探讨富血小板血浆(platelet-rich plasma,PRP)对下肢慢性难愈合伤口的修复作用. 方法 2007年5月-2007年11月,采用PRP注射治疗下肢慢性难愈合伤口47例.男41例,女6例;年龄15~68岁,平均43.2岁.原发疾病:胫腓骨骨折20例,跟骨骨折4例,跖骨骨折1例,下肢多发开放性骨折3例,胫骨骨髓炎10例,股骨骨髓炎1例,足踝部软组织损伤4例,截肢术后感染2例,足部矫形术后感染及跟腱修补术后感染各1例.外院治疗后2~4个月创口未愈合转入合并骨折未愈合23例,细菌培养结果 阳性38例.患者予2次清创加自体PRP伤口内注射,每次间隔2个月. 结果 患者均于首次注射PRP后获随访,随访时间4个月.首次注射PRP2个月后,34例伤口明显缩小,坏死组织及脓苔清除,组织色泽健康,血供良好,外露骨或肌肉组织被新牛肉芽组织覆盖.4个月随访时,无肌肉和骨组织外露患者,创面覆盖率79.3%4±18.O%,总治愈率29.8%.治疗前创口体积(11.8±5.6)mL,治疗后为(2.5±2.7)mL,创口体积缩小(9.3±4.9)mL,治疗前后创口体积比较差异有统计学意义(P<0.05).术前23例合并骨折未愈合者,随访4个月时骨折完全愈合9例,骨痂生长明显增多12例,无明显改变2例,均无骨髓炎征象加重.细菌培养阳性结果 15例. 结论 PRP能有效促进软组织缺损修复,加速下肢慢性难愈合伤口愈合.  相似文献   
106.
During revision anterior cruciate ligament (ACL) surgery, femoral interference screws frequently require removal. This may lead to significant tunnel widening and possible graft fixation failure as a result. Solutions include drilling the revision tunnel in a different location, using stacked interference screws, or using bone graft to fill the defect. Autogenous iliac crest graft and allograft are both used, but there are significant comorbidities associated with each. We developed a new technique for harvesting autogenous bone graft that avoids many of the complications associated with other graft sources. By use of the existing surgical incision from the initial harvest of the bone–patellar tendon–bone autograft, bone from the medial tibial metaphyseal safe zone is harvested via an OATS tube harvester (Arthrex, Naples, FL). A bone plug 1 mm larger in size than the femoral defect is harvested and arthroscopically inserted via a press-fit technique. At 3 months after bone grafting, patients undergo revision ACL reconstruction. The proximal tibial metaphysis is a safe bone graft harvest site in revision ACL surgery and offers an effective method for filling large bony defects, allowing anatomic reconstruction of the ACL after bone healing has occurred. Furthermore, it eliminates the problems associated with allograft or use of a remote graft donor site.  相似文献   
107.
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   
108.
109.
[目的]观察人骨髓间充质干细胞在速固化磷酸钙骨水泥支架中的增殖和生长情况。[方法]将速固化壳聚糖-磷酸钙骨水泥支架材料预先成形。采用全骨髓法分离人骨髓间充质细胞并在体外对细胞进行培养和扩增。72h首次换液,细胞融合80%传代,取第3代细胞用于实验。将细胞与磷酸钙骨水泥支架复合培养,分别利用四甲基偶氮唑蓝MTT法及扫描电镜等检测细胞在材料中的增殖和生长情况。[结果]用酶标仪检测OD值提示共培养后,支架内的细胞数量逐渐增加。扫描电镜结果显示支架材料内部为多孔结构,孔内见有细胞生长,细胞表面可见分泌颗粒。[结论]速固化壳聚糖-磷酸钙骨水泥对人骨髓间充质干细胞有较好的细胞相容性,细胞可在材料内黏附和增殖,是理想的骨组织工程支架材料。  相似文献   
110.
导航在长骨干骨折髓内钉固定中的应用   总被引:4,自引:0,他引:4  
目的阐述透视导航技术在长骨干(股骨和胫骨)骨折,特别是在术中远端交锁髓内钉固定中的应用。探索在导航条件下术中应用髓内钉图像库开展远端交锁固定的可行性。此外,医用机器人的开发旨在被进一步用来改善手术程序的精确性。方法导航手术下,55例行股骨远端交锁钉固定和36例行胫骨远端交锁钉固定。其中13例术中应用图像库开展远端交锁固定。结果远端交锁固定成功率为97%。结论透视导航在长骨干骨折术中,使远端髓内交锁钉固定成功率增高。图像库的应用可以进一步减少患者和手术人员的X线辐射剂量。  相似文献   
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