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51.
52.
Transfecting genes into tumors, to upregulate major histocompatibility complex (MHC) class I and class II molecules and inhibit MHC class II associated invariant chain (Ii), induces a potent anti-tumor immune response when preceded by tumor irradiation, in murine RM-9 prostate carcinoma. The transfected genes are cDNA plasmids for interferon-gamma (pIFN-gamma), MHC class II transactivator (pCIITA), an Ii reverse gene construct (pIi-RGC), and a subtherapeutic dose of adjuvant IL-2 (pIL-2). Responding mice rejected challenge with parental tumor and demonstrated tumor-specific cytotoxic T lymphocytes (CTLs). We have extended our investigation to determine the relative roles of each one of the four plasmids pIFN-gamma, pCIITA, pIi-RGC, and pIL-2 in conjunction with radiation for the induction of a curative immune response. Upregulation of MHC class I with pIFN-gamma or class II with pCIITA, separately, does not lead to a complete response even if supplemented with pIL-2 or pIi-RGC. An optimal and specific antitumor response is achieved in more than 50% of the mice when, after tumor irradiation, tumor cells are converted in situ to a MHC class I+/class II+/Ii- phenotype with pIFN-gamma, pCIITA, pIi-RGC, and pIL-2. We demonstrate further that both CD4+ helper T cells and CD8+ cytotoxic T cells are essential for induction of an antitumor response because in vivo depletion of either subset abrogates the response. The radiation contributes to the gene therapy by causing tumor debulking and increasing the permeability of tumors to infiltration of inflammatory cells.  相似文献   
53.

Objective

This study was designed to identify the presence, type and origin of bacteria adjacent to the metal implant in the infected region in a canine model of pyogenic vertebral osteomyelitis treated with single-stage anterior autogenous bone grafting and instrumentation.

Methods

Dogs with pyogenic spondylodiscitis underwent one-stage debridement, autogenous bone grafting and titanium plate instrumentation and perioperative antibiotic therapy. The implants and adjacent vertebral bones were removed surgically at various postoperative time points (4, 8, 12 and 24 weeks) for bacteria detection. Bacteria were detected from retrieved spinal implants as well as surrounding bones by culture and/or pyrosequencing methods in 17 (85 %) of all 20 animals. The positive rate for bacteria presence was 45 % by culture and 80 % by pyrosequencing method.

Results

Radiological or macroscopic examination showed no signs for infection recurrence in any animal regardless of bacteria presence at the surgical site. However, organism identical with the causative bacterium for spinal infection was found in only two of nine culture-positive animals.

Conclusion

Within the confines of the study, the use of metallic implants in an infected area did not lead to a clinically relevant infection although bacteria may exist at the surgical site. The use of metallic implants in an infected area of the spine is safe. The metallic implants may not be the “culprit” for the persistence or recurrence of infection.  相似文献   
54.
目的探讨建立长春瑞滨化疗性静脉炎动物模型适宜的给药浓度,为化疗性静脉炎的发生机制研究提供实验基础。方法选择实验用健康家兔28只,采用随机数字表法分为四组各7只。均于一侧耳缘静脉注药建模。第1组注射生理盐水10mL作为阴性对照,其余3组将长春瑞滨用10mL生理盐水溶解,分别按12.5mg/m2、25mg/m2和50mg/m2剂量注射。结果长春瑞滨组静脉炎症反应出现于注射后24h,48h左右表现最显著,约于1周恢复。25mg/m2组、50mg/m2组注射后48h有典型的静脉炎病理变化,50mg/m2组4只家兔分别于药物注射后第7~10天死亡,25mg/m2组家兔无死亡。结论参照人体用量采用长春瑞滨25mg/m2于家兔耳缘静脉化疗,能较好建立化疗性静脉炎动物模型。  相似文献   
55.
Dear Editor,
I am Dr. Hui-Rong Chen, from the Department of Urology in Shanghai First People's Hospital at Shanghai Jiao Tong UnNersity, Shanghai, China. Premature ejaculation (PE) is a common sexual dysfunction, affecting approximately 20%-30% of sexually active men. According to intravaginal ejaculatory latency time (IELT) of l min, the incidence is approximately 1%-3%.1 PE is significantly associated with many personal and negative consequences, such as distress, frustration, and avoidance of sexual intimacy due to the inability of successful delayed ejaculation, α1-adrenergic blockers were effective in delaying ejaculation in approximately 50%-67% of the cases.2,3 Recently, abnormal ejaculation, an adverse infrequent side effect associated with the use of α1A-adrenergic blockers such as silodosin or tamsulosin, has drawn significant attention. Clinical studies suggested that this represents a relative anejaculation rather than a retrograde ejaculation. We present here the study to investigate the role of urethral pressure profile (UPP) on treating PE by tamsulosin.  相似文献   
56.
气管内插管全麻患者术后咽喉部并发症研究进展   总被引:1,自引:0,他引:1  
全麻手术中采用气管内插管常常造成咽喉部的创伤和病变,并导致咽喉部术后并发症的产生,如咽喉炎、声嘶和吞咽困难等。本文针对气管内插管的全麻患者术后咽喉部并发症的发生原因及其主要干预措施进行综述,为临床治疗及护理此类患者,提高患者舒适度提供理论依据。  相似文献   
57.
临床路径在病人健康教育中的应用现状及展望   总被引:6,自引:0,他引:6  
王菊香  鲁才红 《护理研究》2007,21(6):1513-1515
介绍了临床路径在病人健康教育中的应用范围及实施状况,提出健康教育路径将更好地契入诊疗临床路径中,以及病人健康教育路径书的规范化及变异管理规范化的发展方向。  相似文献   
58.
More than 14,000 people die from invasive transitional cell carcinoma (TCC) of the urinary bladder yearly in the United States. Cyclooxygenase (COX)-inhibiting drugs are emerging as potential antitumor agents in TCC. The optimal in vitro or in vivo systems to investigate COX inhibitor antitumor effects have not been defined. The purpose of this study was to determine COX-1 and COX-2 expression and antitumor effects of COX inhibitors in human TCC cell lines (HT1376, RT4, and UMUC3 cells) and xenografts derived from those cell lines. COX-2 expression (Western blot, immunocytochemistry) was high in HT1376, modest in RT4, and absent in UMUC3 cells in vitro. Similarly, COX-2 expression was noted in RT4 but not UMUC3 xenografts. COX-2 expression in HT1376 xenografts was slightly lower than that observed in vitro. None of four COX inhibitors evaluated (celecoxib, piroxicam, valeryl salicylate, and NS398) reduced TCC growth in standard in vitro proliferation assays at concentrations that could be safely achieved in vivo (< or =5 micromol/L). Higher celecoxib concentrations (> or =50 micromol/L) inhibited proliferation and induced apoptosis in all three cell lines. Celecoxib or piroxicam treatment in athymic mice significantly delayed progression of HT1376 xenografts, which express COX-2, but not UMUC3 xenografts that lack COX-2 expression. In conclusion, standard in vitro assays were not useful in predicting COX inhibitor antitumor effects observed in vivo. Athymic mice bearing TCC xenografts provide a useful in vivo system for COX inhibitor studies. Results of this study provide justification for further evaluation of COX inhibitors as antitumor agents against TCC.  相似文献   
59.
五常法在手术室腹腔镜管理中的应用   总被引:7,自引:0,他引:7  
目的:探讨确保腹腔镜手术的顺利进行,提高手术质量,延长设备、器械使用寿命的方法。方法:总结我院自1993年3月开展腹腔镜手术以来,五常法在手术室腹腔镜管理中的应用情况。结果:无一例因腹腔镜器械故障或欠缺而影响手术的顺利进行。结论:五常法的应用减少了手术护理工作中的缺陷,增强了手术室护士工作的主动性和计划性,增强了手术护士的工作成就感。  相似文献   
60.
OBJECTIVE: The purpose of this study was to evaluate micro flow imaging (MFI) in depicting the vascular architecture of hepatocellular carcinoma (HCC) and the correlation between pathologic differentiation and the intratumoral vascular architecture pattern. METHODS: Micro flow imaging and contrast harmonic imaging (CHI) were performed in 37 patients with HCC. A sulfur hexafluoride-filled microbubble contrast agent was used. The enhancement level and intratumoral vessels were evaluated on CHI. The vascular architecture of each tumor was evaluated on MFI. Pathologic differentiation of the tumors was classified according to the Edmondson grading system. RESULTS: All 37 HCCs showed hyperenhancement in the arterial phase and hypoenhancement in the portal and late phases on CHI. Intratumoral vessels in the arterial phase were visualized in 20 (54.1%) HCCs. On MFI, the vascular architecture in all lesions was clearly delineated and categorized into 3 patterns: cotton, shrubbery, and deadwood, identified in 12 (32.4%), 22 (59.5%), and 3 (8.1%) of the tumors evaluated, respectively. A chi(2) test showed that pathologic differentiation significantly correlated to the vascular pattern (P = .006). Three (75%) of 4 Edmondson grade I HCCs showed the cotton pattern; 18 (75.0%) of 24 Edmondson grade II HCCs showed the shrubbery pattern; and the deadwood pattern was shown only in Edmondson grade III and IV HCCs. CONCLUSIONS: The MFI technique is more effective in depicting the intratumoral vascular architecture. The vascular architecture pattern correlates with pathologic differentiation of HCC.  相似文献   
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