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41.
单平面和多平面截骨术治疗脊椎后凸的损伤特点   总被引:1,自引:0,他引:1  
目的 探讨单平面截骨Dick钉固定和多平面截骨Luque捧固定治疗脊柱后凸的生物力学损伤特点。方法 将12具新鲜小牛胸腰段脊柱标本(T8~L5)随机分成完整组(INT组)、单平面截骨Dick钉固定组(Dick组)和多平面截骨Luque俸固定组(Luque组),每组4具。以侧弯方式进行超生理负荷试验,记录载荷值的变化并观察损伤模式,绘制损伤试验的载荷——位移曲线。结果 损伤试验提供了标本出现屈服的负荷值及损伤方式。INT组、Dick组和Luque组屈服的负荷值依次为3600、2800和7160N。结论 实验中多平面截骨Luque棒固定的最大抗屈服能力稍优于单平面截骨Dick钉固定组,但不足以构成临床应用中决定取舍的依据。  相似文献   
42.
: A rising prostate specific antigen (PSA) following treatment for adenocarcinoma of the prostate indicates eventual clinical failure, but the rate of rise can be quite different from patient to patient, as can the pattern of clinical failure. We sought to determine whether the rate of PSA rise could differentiate future local versus metastatistic failure.

: Two thousand six hundred sixty-seven PSA values from 400 patients treated with radiotherapy for localized adenocarcinoma of the prostate were analyzed with respect to PSA patterns and clinical outcome. Patients had received no hormonal therapy or prostate surgey and had ?4 PSA values post-treatment PSA rate of rise, determined by the slope of the natural log, was classified as gradual (< 0.69 log (ng/ml)/year, or doubling time (DT) > 1 year), moderate (0.69-1.4 log (ng/ml)/year, or DT 6 months-1 year), or rapid [>1.4 log (ng/ml)/year, or DT < 6 months].

: SIxty-one percent of patients had non-rising PSA following treatment; 25% of patients with rising PSA developed clinical failure, and 93% of patients with clinical failure had rising PSA. The rate of rise discerned different clinical failure patterns. Local failure occurred in 23% of patients with moderate rate of rise versus 7% with gradual rise (p = 0.0001). Metastatic disease developed in 46% of those with rapid versus 8% with moderate rise (p < 0.0001). By multivariate analysis, in addition to rate of rise, PSA nadir and rate of decline predicted local failure; those with post-treatment nadir of 1–4 ng/ml were five times more likely to experience local failure than nadir < 1 ng/ml (p = 0.0002). Rapid rate of rise was the most significant independent predictor of metastastic failure.

: The rate of PSA rise following definitive radiotherapy can predict clinical failure patterns, with a rapidly rising PSA indicating metastatic recurrence and moderately rising PSA local recurrence. This information could potentially dirent therapy; if the rise predicts metastatic failure hormonal therapy could be cosidereed, while aggressive salvage therapy may benefit subclinical local recurrence identified by a moderate rate of PSA rise.  相似文献   

43.
The effects of a single dose of irradiation on the biomechanical parameters of the fracture healing process were studied in a rat model. Intramedullary pinning was performed before production of a closed femoral midshaft fracture. The experimental group was exposed to 900 rad 3 days after fracture and was compared with a control group with a similar fracture that received no irradiation. Animals were killed at intervals ranging from 2-16 weeks after surgery and the bones were tested until failure in torsion. In the irradiated groups, a delay of 4 weeks was noted in the biomechanical parameters associated with fracture healing (torque to failure, torsional stiffness, angle to failure, and biomechanical stage). Despite this delay in the normal temporal progression, the staging and stiffness approached normal controls within an 8-week period. However, the torque to failure remained below normal levels at the conclusion of this study. These results differ from a previous study using an open fracture model.  相似文献   
44.
目的总结分析伴有马尾神经损害的腰椎间盘突出症的临床特点,并对手术方法进行探讨.方法对采用撑开式椎板成形术治疗的26例伴有马尾神经损害的腰椎间盘突出症患者的临床资料进行回顾性分析.结果获得随访资料26例平均随访6年5个月,根据Macnab疗效标准,优17例,良7例,可1例,差1例.优良率92.3%.结论伴有马尾神经损害的腰椎间盘突出症的临床症状重,手术治疗需要彻底减压方能取得优良效果.采用撑开式椎板成形术显露,除具有全椎板切除的优点,还不破坏腰椎后柱的稳定性,最大限度地保留了脊柱的完整性,减小了手术创伤,是行之有效的手术方法.  相似文献   
45.
食管癌切除术并发胸导管损伤的早期诊断及治疗   总被引:2,自引:1,他引:1  
我院1990年至1993年共施行食管癌切除术160例,术中胸导管损伤5例,发生率为2.1%,5例中3例于术中发现并及时处理,未发生乳糜胸,另2例于术后并发乳糜胸才诊断,经早期剖胸手术治愈,本文介绍了食管癌切除术并发胸导管损伤的早期诊治体会。  相似文献   
46.
放射线照射对体外培养的骨巨细胞瘤细胞作用的实验研究   总被引:1,自引:0,他引:1  
目的 :对体外培养的骨巨细胞瘤细胞进行放射线照射 ,并观察其效应。方法 :对 6例经临床、X线和病理组织学检查证实的骨巨细胞瘤标本进行体外细胞培养 ,传代后实验组进行放射线照射处理 ,对照组未进行放射线处理。分别采用倒置显微镜观察、台盼蓝染色后计数、MTT法测定和FCM分析来观察放射线照射对体外培养的骨巨细胞瘤细胞的细胞毒性和细胞周期的影响。结果 :放射线照射后 ,体外培养的骨巨细胞瘤细胞可见逐渐发生皱缩和脱落 ,细胞存活率为 8 2 7%~ 13 5 0 % ,细胞毒性指数为 83 19% ,FCM分析显示G0与G1期比例明显增加 ,G2与M期比例明显减少。结论 :放射线照射对体外培养的骨巨细胞瘤细胞有较强的细胞毒性作用  相似文献   
47.
血小板第4因子对辐射损伤小鼠免疫功能的保护作用   总被引:1,自引:0,他引:1  
目的:探讨血小板第4因子(plateletfactor4,PF4)对辐射损伤小鼠免疫系统的影响。方法:雄性BALB/c小鼠随机分为3组,第1组(单纯照射组)、第Ⅱ组(PF4保护组)、第Ⅲ组(正常对照组),第Ⅱ组在照射前26h及20h腹腔注射PF440μg/kg,全身一次性5Gy60Co—γ射线照射后瑞氏染色法计数外周血淋巴细胞百分数。胸腺、脾脏制成细胞悬液计数后,MTT比色法测定胸腺及脾细胞增殖能力。结果:第Ⅱ组小鼠外周血淋巴细胞百分数下降趋势较第1组明显减慢。胸腺、脾细胞计数,第Ⅱ组明显高于第1组。淋巴细胞增殖试验,第Ⅱ组与第1组相比,小鼠胸腺及脾细胞的增殖能力明显增强。结论:PF4对免疫系统有辐射保护作用,可明显增强辐射损伤小鼠的免疫功能。  相似文献   
48.
Background: Many patients treated for breast cancer with radiotherapy will survive their disease and be at risk for treatment-related sarcoma for many years. Methods: In order to identify patients with post-treatment sarcoma and define this disease, we examined the records of 99 patients treated for sarcoma with a history of antecedent breast carcinoma. Of these patients, 51 were felt to have a sarcoma unrelated to breast cancer treatment and 48 were felt to have a treatment-related sarcoma (secondary to lymphedema and/or radiation). Results: Lymphangiosarcoma of the extremity was the most common histologic subtype of post-treatment sarcoma, accounting for 22 of 48 cases (46%). Twenty-six patients (54%) developed nonlymphangiosarcoma post-treatment sarcoma; all of these were radiation-associated sarcomas. The median latency interval between the diagnosis of breast cancer and the development of sarcoma was 11 years (range 4–44) and was not different between the two groups. However, patients with nonlymphangiosarcoma were significantly younger when diagnosed with breast cancer than were those with lymphangiosarcoma of the extremity (median 43 vs. 51 years, p<0.001). The survival of all 48 patients was poor: 5-year survival was 29%. Five-year survival of patients with other types of post-treatment sarcoma was just as poor as those with lymphangiosarcoma of the extremity (30% vs. 28%, p=0.98). Conclusions: Patients who develop sarcoma after treatment for breast cancer have a poor prognosis whether it occurs as Stewart-Treves syndrome or other types of post-treatment sarcoma. Younger patients may be at higher risk than are older patients for the development of nonlymphangiosarcoma post-treatment sarcoma.Presented at the 46th Annual Cancer Symposium of the Society of Surgical Oncology, Los Angeles, March 18–21, 1993.  相似文献   
49.
本文报道,75mGy/(12.5mGy/min)单次全身X射线照射后9小时用SRBC免疫C57BL/6小鼠,在免疫后4天和7天脾脏、胸腺和下丘脑cAMP含量均降低;而在免疫后4天脾脏去甲肾上腺素、肾上腺素和酪氨酸含量均增高,免疫后7天肾上腺素含量仍持续增高;当连接γ射线65mGy(0.015mGy/min,6h/d)全身照射小鼠后即刻或29小时后免疫,脾脏和下丘脑cAMP含量也均降低。提示,低剂量  相似文献   
50.
目的评价定量检测放射性血脑屏障(BBB)破坏的不同方法,探讨碱性成纤维细胞生长因子(bFGF)对放射性BBB破坏的保护作用。方法60只急性放射性脑损伤模型大鼠(直线加速器6MeV电子束单次照射25Gy)分为单纯照射组和照射前尾静脉注射bFGF组(250ng/kg),并设未照射对照组;分别于照射后2、7和30d采用脑干-湿重法检测脑含水量,并用单次静脉注射3mg/kg伊文氏蓝(EB)后脑组织的EB含量法评估BBB破坏情况。结果照射后脑组织含水量和EB含量均较对照组明显增高,注射bFGF组脑组织含水量和EB含量均低于单纯照射组(P〈0.05)。受照后不同日期的脑组织EB含量差异有统计学意义(P〈0.05),而脑含水量差异没有统计学意义。结论注射EB后检测脑组织,浓度法较干湿重法测脑含水量能更好地反映BBB的破坏情况;bFGF对受照后BBB破坏有保护作用。  相似文献   
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