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91.
目的 从基因水平探讨霍奇金淋巴瘤(HL)组织中H/RS细胞(Hodgkin and Reed-Sternberg cells)是否起源于B细胞、H/RS细胞的克隆性以及与背景淋巴细胞的相互关系。方法 对33例经典霍奇金淋巴瘤(cHL)石蜡刮片组织进行IgH基因重排分析,并对其中6例重排阳性的病例经B细胞特异性激活蛋白(BSAP)免疫标记,将标记阳性的H/RS细胞和背景淋巴细胞进行微切割后进一步行IgH基因重排分析。结果 16例石蜡刮片组织IgH基因重排阳性。对6例经BSAP标记的cHL成功进行了微切割,其中19管H/RS细胞中,有14管出现重排阳性,细胞数目不同的各管阳性率无显著性差异(P=0.290);12管背景淋巴细胞有2管出现重排阳性,H/RS细胞与背景淋巴细胞的阳性率有显著性差异(P=0.002)。结论 支持H/RS细胞来源于B细胞的理论,认为部分背景淋巴细胞可能具有瘤性增生活性,参与H/RS细胞的前体细胞组成。  相似文献   
92.
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   
93.
MUC-1基因在胃癌和外周血中的表达及临床意义   总被引:1,自引:0,他引:1  
目的:检测胃癌MUC-1的表达情况及其与临床分期和转移的相关性。方法:应用逆转录聚合酶链反应(RT-PCR)和免疫组化方法检测胃癌活检标本和外周血中MUC-1基因和蛋白的表达水平。结果:在56例胃癌病例中MUC-1 mRNA阳性表达率为48.2%,MUC-1蛋白阳性表达率为53.6%,临床分期中I和II期病人阳性表达率MUC-1 RNA为33.3%,MUC-1蛋白为40%,而-Ⅲ期病人则分别高达65.4%和69.2%,二者差异有显著性意义(P<0.05),在淋巴结转移的患者中外周血的癌细胞MUC-1高表达,阳性率为73%,结论:MUC-1是一种较好反映胃癌恶性程度和转移性的肿瘤标志物。  相似文献   
94.
MRI在颅内生殖细胞瘤诊断中的作用   总被引:4,自引:0,他引:4  
目的:探讨MRI对颅内生殖细胞瘤的诊断价值。方法:对19例经手术和病理证实的颅内生殖细胞瘤患者的MR表现进行分析。结果:19例中,10例位于鞍区,其中男性5例,女性5例,6例位于松果体区,3例位于丘脑基底节区,均男性,其MR表现为(1)T2WI等或稍低信号,T2WI等或销高信号,鞍区和松果体区肿瘤无水肿,丘脑基底节区肿瘤轻至中度水肿和占位效应;(2)Gd-DTPA增强扫描肿瘤呈不均匀或均匀明显强化。结论:MRI的多轴位成像及Gd-DTPA应用有助于颅内生殖细胞瘤的诊断与鉴别诊断;病人性别,发病年龄和肿瘤部位,大小、形态及信号强度具有一定的特点,在多数情况下是可以做出术前诊断的。  相似文献   
95.
甲醛固定源同种异体骨移植材料的体外实验研究   总被引:5,自引:0,他引:5  
OBJECTIVE: To conduct an in vitro study to assess the preliminary possibility of using formalin-fixed, instead of fresh, human bone tissues for allografting. METHODS: Fresh cadaveric bone tissues were fixed by formalin for more than 6 months and dissected into 5 mmx5 mmx5 mm pieces and 5 mmx5 mmx40 mm sticks, followed by chemical treatments to prepare the allograft bone materials. When alls treatments were completed, the bone grafts were centrifuged and their properties and cellular compatibility assessed in comparison with the currently used bone grafts clinically. RESULTS: The residual formaldehyde of the fixed allograft bone material was much below the controlled level and no significant differences were noted between the bone graft materials tested in regard to the chemical and mechanical properties and biocompatibility. CONCLUSION: This material we have prepared may meet the clinical demands for bone grafting, with good biocompatibility and less chance for infection by pathological agents.  相似文献   
96.
目的 探讨原癌基因erbB3、erbB4与细胞凋亡和增殖的关系 ,为该基因作用机制提供新线索。方法 分别采用免疫组化、DNA末端标记技术 (TUNEL法 )和HE染色检测 5 0例宫颈鳞癌中erbB3、erbB4基因蛋白表达及凋亡指数 (AI)和增殖指数 (MI)。结果 宫颈鳞癌中erbB3、erbB4表达率分别为 5 2 .5 %、44 .0 % ,AI、MI值分别为 5 .5 0± 4.10和 4.18± 3 .63 ,随着宫颈癌恶性程度增高、FIGO分期进展、肿瘤体积的增大和淋巴结转移组 ,erbB3、erbB4表达率增加 ,AI、MI值也增高 ,但差异仅在分化程度上有显著性 (P <0 .0 5 )。双变量相关分析显示erbB3、erbB4表达与AI、MI间无相关性 (r3=0 .10 98、0 .12 3 6,r4 =0 .2 15 1、0 .2 5 5 8,P >0 .0 5 )。结论 erbB3、erbB4和AI、MI预示着宫颈癌恶性潜能 ,但不能作为预后有用指标。erbB3、erbB4的作用机制可能不是通过细胞凋亡或增殖起作用  相似文献   
97.
脑卒中患者吞咽障碍及康复效果影像学研究   总被引:14,自引:1,他引:13  
目的探讨电视X线透视吞咽功能检查(videofluoroscopic swallowing study,VFSS)在脑卒中患者吞咽功能评估中的应用价值,观察脑卒中后吞咽障碍发生情况,康复前后患者吞咽功能变化.方法脑卒中患者70例及健康成人80名分别作为研究组与对照组均进行VFSS,比较两组误吸等VFSS异常征象的发生情况.对发现误吸患者进行吞咽功能康复训练4周,训练后复查VFSS,比较训练前后吞咽异常的发生情况变化.结果对照组渗透或误吸、口腔滞留、咽腔滞留的发生率为5.0%,13.4%,25.3%.主要为轻度渗透及口咽腔滞留.研究组渗透或误吸、口腔滞留、咽腔滞留发生率为45.0%,46.5%,48.9%,主要为重度渗透或误吸,中重度口咽腔滞留.其中隐匿性误吸为10次(占总误吸的24.4%).误吸患者康复治疗后渗透或误吸发生率较康复治疗前减少(P<0.05).结论脑卒中后吞咽障碍在康复期仍较为常见,可表现为多种影像学异常.VFSS可确切诊断吞咽异常,进行针对性康复训练,使患者吞咽功能提高.  相似文献   
98.
目的:观察重症急性胰腺炎(SAP)大鼠白血病抑制因子(LIF)在肺组织中表达的时相变化, 探讨LIF在SAP病程及肺损伤中的意义.方法:36只♂SD大鼠随机分为正常对照组(N 组,n=6)、假手术组(Sham组,n=6)和重症急性胰腺炎组(SAP组,n=24).采用胰管逆行灌注50 g/L牛磺胆酸钠的方法复制大鼠SAP模型.用RT-PCR法检测肺组织中LIF mRNA的表达水平,免疫组织化学方法检测NLIF在肺组织中的表达变化.结果:SAP组3 h后肺组织LIF mRNA的表达量明显高于对照组和假手术组(灰度值:1.018± 0.065 vs 1.451±0.067,1.322±0.072,P<0,05), 并且6,12,24 h持续升高(0.853±0.058,0.635 ±0.064,0.582±0.089)(P<0.01).同样,SAP组 LIF蛋白表达在3和6 h后明显高于对照组和假手术(127.36±2.76,122.53±2.43 vs 159.46 ±2.78,156.35±3.12,P<0.05),并且12,24 h后也维持在很高的水平(109.37±2.87,102.42± 2.27).结论:LIF作为促炎症因子参与了SAP肺组织的炎症反应.  相似文献   
99.
A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered.  相似文献   
100.
This paper reports the prevalence of chronic esophagitis and nutritional status among 538 young persons aged 15 to 26 years from the high risk area for esophageal cancer. Of these subjects, 166 were from households with history of esophageal cancer and 372 were from households without history of esophageal cancer. The Incidences of chronic esophagltis among male and female adolescents were 37. 6% and 36% respectively, which was significantly higher than those in the low risk area (17%). The frequency of chronic esophagltis in the adolescents in the households with history of esophageal cancer was aiso higher than in those In the households without history of esophageal cancer. The deficiencies of vitamins, especially of riboflavin and ascorbate, are prevalent and severe among these adolescents. Ascorbate deficiency Is correlated with the severity of the chronic esophagltis. These results indicate that chronic esophagltis may be involved in the natural history of esophageal carclnogenesis. Nutrient defic  相似文献   
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