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71.
目的检测以质粒pIRES为载体构建的带有全序列癌胚抗原(CEA)基因的核苷酸疫苗对机体特异性抗肿瘤免疫反应的激活效果。方法将CEA基因片段连接于真核表达质粒pIRES中,用肌肉注射方法接种核酸疫苗;检测CEA在小鼠肌肉组织中的表达情况及其对小鼠脾细胞CEA特异性细胞免疫反应的激活效果。结果小鼠经肌肉注射质粒后,免疫组化证实该核酸疫苗可在体内有效表达CEA;分子免疫检测显示注射后小鼠特异性淋巴细胞增值反应明显并且伴有自然杀伤细胞NK活性显著增高。结论实验所构建的核酸疫苗pIRESCEA可在体外及小鼠体内高效表达并表现出良好的细胞免疫原性。  相似文献   
72.
Although case reports of alpha-fetoprotein (AFP)-producing adenocarcinoma other than hepatocellular carcinoma have gradually increased in number, AFP-producing adenocarcinoma of the endometrium is very rare. The patients universally complain of abnormal vaginal bleeding. The patient presented with complaints of epigastric discomfort. No vaginal bleeding was observed. Serum AFP concentration was 453 ng/mL, and lens culinaris agglutinin-reactive AFP percentage of total AFP was increased to 67%. Radiologic imaging and endoscopy did not provide evidence of any primary carcinoma in the liver and gastrointestinal tract. To investigate the unknown origin of high AFP, Pap smear of the endometrium followed by fractional curettage was performed and revealed adenocarcinoma of the endometrium. Radical hysterectomy with pelvic lymph node dissection and partial omentectomy was performed. Histologic study showed a mixture of major AFP-negative endometrioid adenocarcinoma and minor medullary proliferation of the AFP-positive hepatoid adenocarcinoma cells with eosinophilic cytoplasm and hyaline globules. After the surgery followed by four courses of weekly carboplatin and paclitaxel administration, serum levels of AFP dropped into normal range. The possible existence of AFP-producing adenocarcinoma of the endometrium should be considered in a postmenopausal woman even if there is no vaginal bleeding, when AFP-producing tumor is clinically suspected and the imaging studies fail to confirm the diagnosis.  相似文献   
73.
目的检测结直肠癌患者血浆血栓调节蛋白(TM)的水平,探讨血浆TM与结直肠癌临床特征及转归的关系。方法用酶联免疫吸附夹心法检测62例结直肠癌患者的血浆TM水平,并动态观察50例手术前后血浆中血栓TM的水平。结果结直肠癌组血浆TM水平(8.41±5.87)ng/ml,明显高于正常人对照组(5.30±0.86)ng/ml(P<0.01);分层分析发现,早期患者血浆TM水平(5.36±0.53)ng/ml,与正常人对照组比较,差异无统计学意义(P>0.05);随病情进展,血浆TM水平进行性升高[Ⅲ期组(11.20±0.66)ng/ml,Ⅳ期组(13.65±2.41)ng/ml](P<0.01)。手术后血浆TM水平(4.86±0.60)ng/ml,比手术前(8.26±1.36)ng/ml,明显降低(P<0.01)。结论结直肠癌患者血浆TM水平明显高于正常人,并且与结直肠癌的进展呈正相关,监测其水平变化对判断预后有一定参考价值。  相似文献   
74.
Tegaserod is a 5-HT(4) receptor partial agonist approved for the treatment of irritable bowel syndrome in women with constipation and in both men and women with chronic constipation. The efficacy of tegaserod is based on the importance of 5-HT(4) receptors regulating intestinal peristalsis and secretion, and possibly visceral sensory pathways. Our aim was to investigate the effect of tegaserod on colorectal sensitivity using models of normal and exaggerated responsiveness to colorectal distension (CRD). The visceromotor responses (VMR) to CRD at graded pressures (0-60 mmHg) were measured by the number of reflex abdominal contractions. Acute colorectal hypersensitivity was induced by intracolonic infusion of dilute acetic acid. Chronic hypersensitivity was observed in rats following spontaneous resolution of trinitrobenzenesulfonic acid-induced colitis. Rats with normosensitive colons served as controls. Tegaserod (0.1-10 mg kg(-1)) caused dose-dependent reduction of the VMR to CRD in control rats and in those with colonic hypersensitivity. 5-HT(4) antagonists reversed the effects of tegaserod in rats with normosensitive colons, and partially inhibited effects in rats with colonic hypersensitivity. Central administration of tegaserod had no inhibitory effect. These results support the assumption that colonic hypersensitivity could be normalized by tegaserod acting, at least in part, through peripheral 5-HT(4) receptors.  相似文献   
75.
We describe a 54-year-old woman with primary pulmonary adenocarcinoma showing a characteristic papillary architecture and prominent cilia formation. Immunohistochemically, the tumor cells were positive for carcinoembryonic antigen (CEA), epithelial membrane antigen (EMA) and Leu Ml, and negative for lactoferrin and surfactant apoprotein. An ultrastructural study also indicated differentiation toward bronchial surface epithelial cells. To our knowledge, this type of neoplasm has not been reported as peripheral-type adenocarcinoma of the lung. Acta Pathol Jpn 42: 745–750, 1992.  相似文献   
76.
目的 观察诱导分化剂苯乙酸 (Phenylacetate,PA)抑制结直肠癌细胞HCT 8增殖过程中C myc基因表达的变化。方法 体外细胞培养 ,运用流式细胞技术观察苯乙酸对HCT 8细胞凋亡的影响。应用原位分子杂交方法观察应用PA后对HCT 8细胞C mycmRNA表达的情况。结果 PA组HCT 8细胞G1期比例从 32 3%增加到 6 1 0 % ,S期比例从 5 9 6 %下降到 2 9 7%。PA治疗后HCT 8细胞C mycmRNA表达阳性表达率为 (12 0 5± 7 92 ) % ,显著低于非治疗组中的阳性率 (5 5 15± 2 1 6 4 ) % ,P <0 0 1。通过细胞周期的检测发现 ,PA抑制大肠癌细胞HCT 8增殖的方式为抑制细胞周期G1期比例。结论 PA通过下调结直肠癌细胞C mycmRNA的生成以及细胞生长G1期阻滞在肿瘤诱导分化治疗方面发挥作用  相似文献   
77.
核转录因子κB(nuclearfactorofkappaB ,NF κB)是一种多极性核转录因子 ,参与调控多种与免疫反应、凋亡、炎症、肿瘤形成和转移有关的基因表达。近年来 ,NF κB在肿瘤发生、耐药、转移中的作用及其机制逐渐成为医学研究的热点。本文主要综述了NF κB的结构、生物学功能及其抗凋亡诱发肿瘤的机制 ,NF κB调控的前列腺癌相关基因的表达和调控 ,NF κB参与前列腺癌浸润与转移的机制及其在前列腺癌基因治疗中的可能策略等。  相似文献   
78.
目的探讨全结直肠切除回肠贮袋肛管吻合术(ileal pouch-anal anastomosis,IPAA)后患者控便能力与肛管压力的关系。方法对16例患者行IPAA术,术后1个月、6个月、1年时随访控便能力,并检测肛管压力。结果12例获得随访,平均2.3(1.0~4.5)年,患者排便次数在术后1年时明显少于术前和术后1个月(P<0.05);肛管静息压和最大缩柞压在术后1个月、6个月时明显低于术前(P<0.05),但在术后1年时已有明显改善,与术前相似(P>0.05)。结论IPAA术后肛管压力的改变可能与患者的控便能力有关。  相似文献   
79.
Aim: The prognosis of patients with disseminated colorectal carcinoma is poor except for those with single organ pulmonary or hepatic metastases. The objective of the present study was to evaluate the result of pulmonary metastasectomy for colorectal secondary and to identify the prognostic factors. Methods: This was a retrospective study of 80 patients who had pulmonary metastasectomy for pulmonary secondary from colorectal carcinoma in Queen Elizabeth Hospital, Hong Kong. Results: The overall 5‐year and 10‐year survival rates of the entire cohort were 42.5% and 35.5%, respectively. High premetastasectomy carcinoembryonic antigen (> 20 μg/dL), short disease‐free interval (< 12 months) and incomplete resection were the independent prognostic factors. Neither the characteristics of the primary colorectal tumour nor the number of metastatic nodules had a significant contribution to the long‐term survival. Six patients underwent second pulmonary metastasectomy and three were still free from tumour recurrence after the second operation. Conclusion: Patients with pulmonary metastases from colorectal carcinoma would benefit from pulmonary metastasectomy. High premetastasectomy carcinoembryonic antigen and short disease‐free interval were negative predictive factors for survival. Long‐term follow‐up study is required, as recurrence can occur more than 5 years after pulmonary metastasectomy. Also, whether the survival benefit is due to surgical treatment effect or lead‐time bias remains undecided.  相似文献   
80.
目的探讨如何通过放大内镜观察到的大肠粘膜腺管开口类型发现早期大肠癌及癌前病变。方法2001年8月~2002年2月结肠镜检查139例大肠病变,采用内镜下粘膜染色技术,结合放大内镜、实体显微镜观察腺管开口分型(pit分型)并与病理诊断对照,pit分型采用工藤分型。结果139例患者中发现大肠息肉124例,进展期癌9例,侧向发育型肿瘤(LST)型病变5例,ⅡC病变1例。LST直径10~50 mm,其中ⅢL型1个,Ⅳ型4个。本组放大内镜与病理、实体镜诊断符合率较高。结论大肠腺管开口对于判断肿瘤性、非肿瘤性病变以及早期大肠癌具有重要意义,如发现有Ⅴ型腺管开口时则高度提示早期癌的可能。  相似文献   
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