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141.
David R. Young Lih-Yuann Shin Michael G. Rock Frank J. Frassica Petri Virolainen Edmund Y. S. Chao 《Journal of orthopaedic research》1997,15(5):773-780
The reconstruction of large bone and joint defects after the resection of malignant tumors remains a major challenge. Chemotherapy has significantly lowered the risk of metastasic disease, but complications associated with reconstructive techniques continue to result in late morbidity. In the present study, biomechanical torsion testing, gait analysis, and histomorphometric and scanning electron microscopic evaluations of 24 dogs were used to examine the effects of preoperative and postoperative administration of cisplatin on the biologic fixation of a porous-coated segmental replacement prosthesis. The chemotherapy consisted of four cycles of cisplatin administered at a dosage of 75 mg/m:2 preoperatively or postoperatively. The healing was enhanced by use of an autogenous corticocancellous bone graft. The graft was placed evenly around the prosthesis and the adjacent femoral cortex. Mechanical analyses of torsional stiffness, yield strength, and maximum strength revealed no statistically significant differences between the groups at 12 weeks. Such lack of difference was mainly due to the penetration of highly organized fibrous tissue into the porous surface; this provided strong fixation of the implant to bone even in the absence of bone ingrowth. Although bone ingrowth into the prostheses was not affected, electron microscopic, histomorphometric, and radiologic analyses showed a clear difference in the formation of new bone around the prosthesis. Preoperative chemotherapy did not alter the formation of new bone, but specimens from animals treated postoperatively with cisplatin showed significantly less bone graft resorption and less new bone formation. Hence, the effect of cisplatin administration caused only a temporary delay, not a permanent effect, on extracortical capsule formation. The formation of extracortical bone and soft tissue might prevent debris-incised osteolysis and, therefore, prevent late complications by forming a tight capsule around the bone-prosthetic interface. 相似文献
142.
Reoperative Thyroid Surgery 总被引:4,自引:0,他引:4
Reoperative thyroid surgery is an uncommon operation associated with a high complication rate. We retrospectively reviewed the data of 115 patients to study the incidence of complications after reoperative thyroid surgery. There were 107 women and 8 men (13.4:1.0) with an average age of 42.8 years (range 18–80 years). The most frequent indication for reoperation was completion thyroidectomy for a carcinoma identified by permanent sections (50 patients, 43.5%). Reoperative surgery was performed on 13 (11.3%) patients with recurrent thyroid cancer. The remaining 52 patients underwent reoperation for recurrent thyrotoxicosis (12 patients, 10.4%), recurrent nodular goiter (28 patients, 24.3%) or recurrent multinodular goiter (12 patients, 10.4%). Seven patients with recurrent nodular goiter and one patient with recurrent thyrotoxicosis underwent total thyroidectomy for the presence of malignancies that were identified by frozen sections. Overall, the interval between the initial and reoperative procedures ranged from 1 day to 33 years (2335 ± 272 days). The length of hospital stay was 5.8 ± 0.5 days. The length of time needed for reoperative thyroid surgery was 122.0 ± 6.2 minutes. There was no 30-day perioperative mortality. The postoperative complications consisted of transient hypoparathyroidism in six patients (5.2%), permanent hypoparathyroidism in two patients (1.7%), transient RLN palsy in 3 patients (2.6%), and permanent recurrent laryngeal nerve palsy in two patients (1.7%). Reoperative thyroid surgery can be performed safely with little morbidity to the patient. 相似文献
143.
144.
目的:探讨意外伤害及事故倾性的家族聚集性,为将来阐明遗传因素在其中的作用提供初步线索。方法:以事故倾性儿童为先证者,采用病例对照研究方法研究579个核心家系(291个先证家系和288个对照家系),分析意外伤害及事故倾性的家族聚集性。结果:病例组有36.4%核心家系至少有一名成员发生过伤害,高于对照组9.0%,差异有统计学意义。病例组的父、母、同胞伤害发生率均高于对照组(差异有显著性)。但病例组与对照组一级亲属的事故倾性发生率无显著性差异。多因素Logistic回归分析发现,父、母、同胞发生伤害都是儿童事故倾性的危险因素,儿童喜欢冒险、不能集中精力也和事故倾性有关联。结论:意外伤害存在家族聚集性,遗传因素可能在其中发挥一定作用。没有发现事故倾性具有家族聚集性。 相似文献
145.
It has been assumed that, when properly implanted, a biologically fixed device is less prone to loosening and probably to fatigue failure as well. This case demonstrates that many of the known risk factors of loosening or fatigue fracture of cemented tibial replacement devices must be considered when using devices designed for biologic fixation. Age, weight, axial alignment, and bone substrate have been identified as probable contributing factors to failure in the case reported here. Manufacturing technique and changes in material properties associated with porous coating should also be carefully tested for factors predisposing the components to fatigue failure. 相似文献
146.
Rupture of the tendon of the long head of the biceps brachii. Surgical versus nonsurgical treatment 总被引:2,自引:0,他引:2
E M Mariani R H Cofield L J Askew G P Li E Y Chao 《Clinical orthopaedics and related research》1988,(228):233-239
Twenty-seven shoulders (in 26 patients) that had surgical repair of a rupture of the long head of the biceps tendon between 1962 and 1981 were evaluated at three to 22 years after injury (mean, 13 years). Thirty similar patients had been treated nonsurgically and were evaluated two to 15 years (mean, 4.6 years) after tendon rupture. Biomechanical testing was performed on ten patients in the surgical group and 13 in the nonsurgical group. Residual arm pain was infrequent in both surgically and nonsurgically treated groups. Residual subjective weakness at the elbow was reported in four of the surgical group and in 20 of the nonsurgical group. Surgically treated patients returned to work later than nonsurgical patients; however, 11 in the nonsurgical group were not able to return to full work capacity, versus only two in the surgical group. On biomechanical testing, the nonsurgical group had lost a mean of 21% of supination strength and 8% of elbow flexion strength but had no weakness in grip, pronation, or elbow extension. The surgical group had lost no strength in any of these testing modes. 相似文献
147.
黄连细胞二步法悬浮培养生产黄连生物碱类成分的探索 总被引:6,自引:0,他引:6
为提高用植物细胞培养生产镒生代谢产物的单位产量,作者对黄连细胞采用二步法悬浮培养生产黄连生物碱进行了探索。结果显示:黄连细胞采用一步法悬浮培养6周,细胞干,鲜重产率分别为20.96g/L和174.92g/L,增重约700%,细胞中总生物碱含量为14.79mg/g.cell dw,培养基中生物碱量为12.96mg/L,每升培养液共可收获生物碱323mg。采用先在生长培养基中培养3周,在合成碱量为12 相似文献
148.
复合抗氧化剂对荷瘤大鼠60Co γ射线局部照射时血液氧化损伤的影响 总被引:10,自引:0,他引:10
目的探讨荷瘤大鼠60Co γ射线局部照射时血液学氧化损伤以及复合抗氧化剂抗损伤作用. 方法采用Walker-256肿瘤细胞株接种大鼠皮下,得到实体瘤,摘除实体瘤分割成小块植入大鼠的右后腿皮下,制成大鼠荷瘤模型,将荷瘤大鼠分成3组,分别为肿瘤组、照射组和抗氧化剂保护组,同时选取正常大鼠作为阴性对照组. 抗氧化剂保护组每日给予复合抗氧化剂ig,分次对照射组和抗氧化剂保护组的荷瘤大鼠进行60Coγ射线局部照射4次,每次间隔1 wk,累计剂量为47 Gy,最后一次照射后7 d,活杀大鼠,取全血和血清测定过氧化氢酶(CAT)、丙二醛(MDA)、总超氧化物歧化酶(T-SOD)和总蛋白. 结果照射组的MDA含量显著高于非照射组和抗氧化剂保护组(347 μmol*g-1 vs 292, 305和196 μmol*g-1, P<0.05),复合抗氧化剂显示出良好的保护作用. 而照射组的抗氧化酶类如总超氧化物歧化酶(T-SOD)活性显著低于非照射组和抗氧化剂保护组(3.65 μkat*g-1 vs 4.05, 4.82和4.70 μkat*g-1, P<0.05),CAT的活性在照射组显著低于肿瘤组和抗氧化剂保护组(362 K*g-1 vs 677和672 K*g-1, P<0.05). 结论 60Co γ射线局部照射可以产生自由基引发的全身氧化损伤,高效的复合抗氧化剂可以起到有效的保护作用. 相似文献
149.
目的:探讨线粒体呼吸链细胞色素C氧化酶(COX)活性异常在老年性聋发病中的作用机制.方法:免疫组化法检测老年性聋大鼠耳蜗COX活性.结果:与正常对照组相比,实验组老年性聋大鼠耳蜗中COX活性降低.结论:耳蜗组织中COX活性降低在老年性聋的发病中起一定作用. 相似文献
150.
The significance of epithelial differentiation in mixed mesodermal tumors of the uterus. A clinicopathologic and immunohistochemical study 总被引:6,自引:0,他引:6
Mixed mesodermal tumors and carcinosarcomas of the uterus are classified as sarcomas. However, in other sites, malignant biphasic tumors may be classified as carcinomas, mesotheliomas, or sarcomas. In order to clarify their behavior and patterns of differentiation, we performed a clinicopathologic and immunohistochemical study of 22 cases aimed at analyzing the pattern of spread and histologic appearance of the metastasis, as well as the distribution of intermediate filaments in the primary tumor and the metastasis. Four monoclonal antibodies (Mabs) were used to detect epithelial lineage, three that recognize keratin (AE1/AE3, CAM5.2, MAK6) and one that recognizes epithelial membrane antigen (EMA). A Mab against vimentin was also used. Metastases involved the omentum, pelvic peritoneum, ovaries, fallopian tubes, pelvic or para-aortic lymph nodes, liver parenchyma, and tonsil. These metastases were composed of carcinoma only. Lymphatic/vascular invasion was identified in 11 cases; it consisted exclusively of carcinoma. In all 12 cases evaluated immunohistochemically, keratin and EMA were identified in the majority of the cells in the epithelial component and in a more focal distribution in the spindle cell component in 11 (92%). Vimentin was detected in the majority of spindle cells in nine cases (75%) and in a more focal distribution in the epithelial component in six cases (50%). In the spindle cell component, keratin and EMA were present in widely scattered individual spindle-shaped and rounded cells, within solid clusters of rounded cells, and in nests of cells with small lumens. The distribution of keratin, EMA, and vimentin in the metastases (carcinoma in all instances) was similar to the epithelial component in the primary tumor. Our findings indicate that the epithelial component of these tumors invades lymphatic/vascular spaces and metastasizes, whereas the spindle cell component has limited metastatic potential, if any. Since the behavior of these neoplasms is dictated by the epithelial element, we believe that mixed mesodermal tumors of the uterus should be classified as carcinomas rather than sarcomas. 相似文献