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91.
本文选择汉正街作个体户人群特需医疗卫生服务需求的典型调查。遁过432例分析及与调查人群平均需求率比较,揭示出个体户人群疾病频率低、文化层次低、自费医疗多的卫生现状,以及个体户人群的特需需求率较低和倾向预防性特需服务的需求特征。本文较多地讨论了个体户人群卫生现状、卫生需求的特性及共性,较深地思考了对个体户人群开展特需服务的策略。并结合医学社会化的大趋势理论,指出特需服务的可行和必行。  相似文献   
92.
Anti-idiotypic antibodies are powerful reagents for the study of immunoregulation, and have potential interest as vaccines against tumors and infectious diseases. Three immunization strategies for the production of rat monoclonal anti-idiotope antibodies have been compared in this paper. Male Wistar rats were immunized i.p. and at multiple subcutaneous sites with 750 micrograms of purified monoclonal antibody against Plasmodium falciparum for three times and subsequently boosted by (1) intraperitoneal injection with 750 micrograms of the immunogen, (2) intravenous inoculation with 400 micrograms of the IgG, and (3) intrasplenic immunization with 200 micrograms of the idiotype. With the intraperitoneal boost method, the frequency of hybrids with anti-idiotope activity was 0.3-0.9% with 62.8-85.2% of the seeded wells containing hybrids. In the intravenous boost group, the percentage of hybrids demonstrating anti-idiotope activity increased to 11.0-13.3% with 80.2-97.9% of the hybrid efficiency. When immunized by the intrasplenic boost route, the frequency of anti-idiotope hybrids generated rose to 12.9-16.4% with 82.3-96.6% of the hybrid efficiency. There was no obvious effect of the boost immunizing methods on the generation of rat monoclonal anti-mouse IgG antibodies. These results indicated that the multiple-site immunization followed by intravenous or intrasplenic boost injection was an appropriate immunizing method for the production of monoclonal anti-idiotope antibodies.  相似文献   
93.
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   
94.
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   
95.
96.
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   
97.
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   
98.
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   
99.
目的探讨微创手术在食管平滑肌瘤治疗中的临床应用价值. 方法回顾性分析1996年9月~2002年10月26例食管平滑肌瘤采用微创手术治疗的临床资料. 结果电视胸腔镜食管平滑肌瘤摘除术23例,其中3例(2例胸膜腔紧密粘连,1例肿瘤无法定位)中转开胸(胸腔镜辅助小切口);经颈部食管平滑肌瘤摘除术2例;经食管镜食管平滑肌瘤切除1例.26例手术顺利,术后恢复平稳,无手术死亡及严重并发症,术后病理诊断均为平滑肌瘤.随访2~73个月,平均32.3个月,无复发. 结论电视胸腔镜肌瘤摘除术可作为食管固有肌层平滑肌瘤的首选治疗方法,对于食管粘膜肌层的平滑肌瘤,可考虑经食管镜切除.  相似文献   
100.
目的 :研究环氧化酶 2及其选择性抑制剂塞来昔布和血管生成因子VEGF、FGF 2间的关系 ,从而探讨环氧化酶 2对结肠癌肝转移瘤血管形成的影响。方法 :以细胞培养法建立稳定的结肠癌细胞株HT 2 9和HCT 116 ,利用脾切除法建立结肠癌肝转移动物模型 ,免疫组化检测结肠癌肝转移瘤VEGF、FGF 2蛋白表达。结果 :结肠癌肝脏转移率 ,HT 2 9组、HCT 116组、塞来昔布组分别为 83 33%、16 6 7%、33 33%。肝脏转移瘤VEGF、FGF 2的表达 ,HT 2 9组与HCT 116组、塞来昔布组比较均表达增强 ,有显著统计学意义 (P <0 0 1~ 0 0 5 ) ;塞来昔布组与HCT 116组比较无显著性差异 (P >0 0 5 )。结论 :环氧合酶 2与结肠癌肝转移瘤血管生成密切相关 ,其高表达促进了结肠癌肝转移瘤新生血管生成。其机制可能是上调促血管生成因子VEGF、FGF 2的表达  相似文献   
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