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Limb shortening is a problem associated with surgery for osteosarcoma of the lower extremity in adolescents, as the tumors frequently occur near the epiphysis. Herein we report the use of a less invasive stabilization system (LISS) and an intermittent fixation method to preserve the growth function of epiphysis in an 11-year-old patient with an osteosarcoma of the distal femur.The 11-year-old male presented with left knee enlargement and pain for 2 weeks, and magnetic resonance imaging (MRI) and biopsy were consistent with osteosarcoma of the left distal femur. After preoperative chemotherapy, en bloc tumor resection was performed with margins based on MRI findings preserving the epiphyseal growth plate, the tumor cavity was filled with inactivated bone and bone cement, and a LISS was used to stabilize the femur. Aggressive postoperative chemotherapy was given. Approximately 105 weeks after surgery radiography showed that the distal end of the plate had moved superior to the epiphysis along with bone growth. Locking screws were placed in the distal part of the LISS plate to stabilize the re-implanted bone, and external fixation was not needed.The patient was able to walk with the crutches 1 week postoperatively, and bear weight on the extremity 6 weeks postoperatively. At 6 years after surgery, the patient''s height had increased 52 cm, shortening of the affected limb was only 1 cm, and the circumference of the affected limb was 2 cm smaller than that of the contralateral limb. There was no significant discomfort in the affected limb, and there was no gait abnormality. The patient could jump and run, and could participate in sports including basketball and badminton to the same degree as his peers.In summary, the novel method of bone reconstruction and fixation provided good results in a child with an osteosarcoma of the distal femur. This fixation method preserves the osteogenic function of the epiphysis and restored bone integrity simultaneously, and provides good functional recovery. 相似文献
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经单根冠状动脉与冠状静脉窦同时灌注心肌保护的实验研究 总被引:1,自引:0,他引:1
目的探讨经单根冠状动脉和冠状静脉窦(CS)顺行性/逆行性同时心肌灌注(SARC)的效果。方法将离体猪心分别经左前降支(LAD)、左回旋支(LCX)或右冠状动脉(RCA)中的1支和CS行SARC,再依次向动、静脉灌注通路内注入磁共振造影剂[钆喷替酸葡甲胺(Gd-DTPA)]。应用磁共振成像(MRI)检测心肌内造影剂的分布以及对非灌注冠状动脉回流液进行分析,评估心肌灌注效果。结果SARC期间经单根冠状动脉注入Gd-DTPA不但使其支配区域磁共振信号增强,而且其余2根非灌注冠状动脉的支配区域信号也增强(包括右心室游离壁);而SARC期间经CS注入Gd-DTPA只引起非灌注冠状动脉支配区变亮,灌注冠状动脉的支配区和右心室游离壁的信号强度无改变。SARC期间非灌注冠状动脉收集的回流液速度分别为:LAD 10.5~17.7ml/min,LCX 9.7~15.2ml/min,RCA 4.7~7.8ml/min。结论经单根冠状动脉和CS同时灌注可以提供全面均匀的心肌灌注,足以防止非灌注冠状动脉支配区发生心肌缺血损伤。 相似文献
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Takayuki Sakurai Satoshi Watanabe Minoru Kimura Masahiro Sato 《Reproductive Medicine and Biology》2006,5(1):43-50
Background and Aims: The aim of this study was to determine which mouse strains exhibit tolerance to cooling when fertilized oocytes have been stored at 4°C.
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
Methods: In-vitro -fertilization-derived oocytes of eight mouse strains were incubated at 4°C in 20 mmol/L Hepes-potassium modified simplex optimized medium (KSOM) medium for 0, 24, 48, 60 or 72 h, and then returned to normal culture conditions at 37°C in KSOM medium. The rates of development of cultured oocytes into blastocysts and cell numbers of blastocysts were examined. In some cases, a Comet assay was carried out to evaluate DNA damage. In addition, the effects of β-mercaptoethanol on the development of the 4°C-treated oocytes were assessed.
Results: Of the eight strains tested, BDF1, B6C3F1 and FVB/N strains exhibited relatively higher degrees of tolerance to 4°C treatment and approximately 90%, 83% and 78% of oocytes treated at 4°C for 48 h developed to morphologically normal blastocysts, respectively. Comet assay revealed no clear DNA damage in oocytes treated at 4°C. Treatment with β-mercaptoethanol failed to improve the in vitro survival rate of low-temperature-treated oocytes.
Conclusion: Strain differences were observed in tolerance to cooling treatment when fertilized oocytes were temporarily treated with 4°C, although the reasons for this remain unclear. (Reprod Med Biol 2006; 5 : 43–50) 相似文献
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浅低温心脏不停搏心内手术对心肌保护效果的比较 总被引:2,自引:0,他引:2
目的:探讨浅低温体外循环(CPB)心脏搏动中心内直视手术对心肌保护的效果.方法:40例患者随机分为观察组(浅低温心不停搏组)和对照组(中低温心停搏组).分别在术前、转机、停机及术后6 h、12 h、24 h、48 h、72 h,取冠状静脉窦或中心静脉血样,测定血气分析及血清中肌酸磷酸激酶(CK)及其同功酶(CK-MB)、天门冬氨酸氨基转换酶(AST)、乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)的含量.并取心房间隔肌观察心肌含水量及心肌超微结构的改变.临床观察CPB时间、脱机、呼吸支持、多巴胺应用、严重心律失常和血红蛋白尿等指标.结果:冠脉循环血气、电解质、酸碱水平与体循环的组内组间对比基本一致.CK、CK-MB、AST、LDH两组在CPB和术后均有增加,且以对照组升高显著,与观察组相同时点相比,差异均有显著性(P<0.01).对照组术后MDA明显升高,SOD明显降低(P<0.01),而观察组变化不大.心肌含水量和超微结构观察,对照组变化显著,而观察组轻微改变.临床指标观察,观察组优于对照组.结论:浅低温体外循环心脏不停搏心内直视手术对心肌损伤很轻,有很好的心肌保护效果. 相似文献
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目的 探讨不同器官保存液对大鼠肝脏透明质酸吸收率的影响 ,以评价它们对肝窦内皮细胞的保护作用。方法 大鼠肝脏原位灌洗后 ,分别在UW液、Celsior液或Histidine Tryptopan Ketoglutarate液 (HTK液 )中低温保存 16和 2 4h ,然后用含透明质酸的Kreb Henseleit液在 37℃下连续循环灌注 90min ,分别于灌注 0、15、30、6 0和 90min时检测肝脏对外源性透明质酸的吸收率。结果 低温保存 16h ,再灌注 0、15、30、6 0和 90min时 ,3种保存液保存的肝脏对外源性透明质酸的吸收率均为负值 ,表明肝窦内皮细胞受到一定程度的损伤 ,但UW液和Celsior液对肝窦内皮细胞的保护作用较HTK液为优 (P <0 .0 1) ;保存 2 4h者 ,UW液对肝窦内皮细胞的保护作用优于Celsior液和HTK液。结论 UW液对肝窦内皮细胞具有较强的保护作用 相似文献
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目的:探讨保留盆腔植物神经的直肠癌手术对老年男性患者性功能及排尿功能的影响。方法:1999~2005年因直肠癌手术的170例老年男性患者分为PANP组(含规范的TME手术方法)和非PANP(TME规范情况不详),对两组术后性功能、排尿功能和局部复发率进行回顾性总结、比较。结果:PANP组性功能与排尿功能明显优于非PANP组,但统计学无显著差异(P<0.05)。而PANP组局部复发率低于非PANP组(P>0.05)。结论:老年直肠癌患者应重视性功能和排尿功能的保护。 相似文献
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取正常成人心脏瓣膜36个,置于低浓度广谱抗生素的营养液(RP-MI1640细胞培养液)中灭菌48h,-80℃冰箱初冻,置于液氮中长期保存。灭菌前后瓣膜细菌培养阴性率分别为94.3%和100%,解冻后经光镜、电镜检查证实瓣组织细胞结构正常,组织培养葡萄糖消耗率测定示瓣组织存活良好。临床同种心脏瓣膜原位移植3例,随访6~30个月,瓣功能良好 相似文献
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本试验是在多种食品的基础上,加大照射剂量(吸收剂量为0.1~8.0 kGy)和提高辐照食品在膳食中比例(千重80%以上)的条件下,进行了150d的大白鼠喂养试验。通过对饲料的营养成分分析及其利用,对动物的生长发育、血液学、致突变性及病理学等项指标的检测,结果证明是安全的。本试验结果为今后辐照食品商业化提供了安全的证据。 相似文献