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991.
大肠侧向发育型肿瘤细胞株的建立及其鉴定 总被引:9,自引:4,他引:9
目的 为了深入研究大肠侧向发育型肿瘤(LST)细胞的生物学特性及其发生发展的机制。方法采用人LST组织进行肿瘤细胞建株及细胞分离与原代培养,传代至70代进行细胞鉴定.包括细胞的形态结构分析、染色体分析和免疫组化分析等,并与非LST细胞作对比。结果 LST细胞为上皮来源的肿瘤细胞,多形性上皮细胞占大多数,其有近似肿瘤细胞的生长特性,群体倍增时间为36h;染色体数量为42-66,85%在三倍体范围内,并具有异常染色体核型;免疫组织化学观察ESA、CK20均呈阳性;超微结构具肿瘤细胞样表现和特征。结论成功建立了1个LST细胞株,并命名为LST-R1细胞,为进一步深入研究LST细胞的生物学特性及大肠癌的发生发展机制奠定了基础。 相似文献
992.
目的:探讨维甲酸对单侧输尿管梗阻(UUO)大鼠肾小管间质损害的保护作用.方法:成年清洁级雄性SD大鼠45只,随机分为假手术组(S组)、UUO组(U组)和治疗组(T组),每组15只.假手术组行左输尿管游离,不结扎;UUO组和治疗组行左输尿管结扎.治疗组术后每天给予5 mg/kg全反式维甲酸(ATRA)皮下注射,假手术组和UUO组注射同体积溶剂.于术后第3、7、14 d观察肾小管损害、肾间质炎性细胞浸润程度,免疫组化法观察病变肾组织趋化因子RANTES和TGF-β1表达.结果:与UUO组相比,治疗组肾间质炎性细胞浸润和肾小管损害程度显著减轻(P<0.01),肾组织RANTES和TGF-β1表达显著降低(P<0.01~0.05).结论:维甲酸能减少UUO大鼠肾间质炎性细胞浸润,减轻肾小管损害,抑制RANTES和TGF-β1表达,从而减轻肾脏炎症反应和纤维化. 相似文献
993.
目的 调查分析全国首台AP1000核电机组安装后周围生活饮用水中90Sr和137Cs及食品中137Cs放射性水平及变化。方法 2012—2019年,选取全国首台AP1000核电机组所在的三门核电站周围的4个生活饮用水监测点,分别在丰水期和枯水期采集并测定90Sr和137Cs放射性活度浓度;采集当地产大米、包菜、鲫鱼和鲻鱼,测定分析137Cs放射性活度浓度。结果 2012—2019年,生活饮用水中90Sr和137Cs放射性活度浓度范围分别为1.2~9.8、0.2~8.1 mBq/L;食品中137Cs放射性活度浓度为1.1×10-2~2.8×10-1 Bq/kg,小于《食品中放射性物质限制浓度标准》(GB 14882-94)限制浓度。结论 全国首台AP1000核电机组安装后周围生活饮用水中90Sr和137Cs及食品中137Cs放射性水平平稳,调查数据显示未发现对环境带来影响。 相似文献
994.
目的对自闭症病人给予被动性语言刺激,评价采用功能性磁共振(MR)成像作为判断病人有无语言缺陷的客观指标的可行性。材料与方法本研究为前瞻性研究,研究方 相似文献
995.
Brain abscess and necrotic brain tumor: discrimination with proton MR spectroscopy and diffusion-weighted imaging 总被引:15,自引:0,他引:15
Lai PH Ho JT Chen WL Hsu SS Wang JS Pan HB Yang CF 《AJNR. American journal of neuroradiology》2002,23(8):1369-1377
BACKGROUND AND PURPOSE: Discriminating pyogenic brain abscesses from cystic or necrotic tumors is sometimes difficult with CT or MR imaging. We compared findings of proton MR spectroscopy ((1)H-MRS) with those of diffusion-weighted imaging to determine which technique was more effective for this differential diagnosis. METHODS: Fourteen patients (necrotic or cystic tumor [n = 7]; pyogenic abscess [n = 7]) who underwent 1.5-T (1)H-MRS and diffusion-weighted imaging and had findings of ring-shaped enhancement after contrast agent administration were enrolled in this study. Diffusion-weighted imaging was performed with a single-shot spin-echo echo-planar pulse sequence (b = 1000 s/mm(2)). The apparent diffusion coefficient and ratio were also measured. RESULTS: Spectra for two patients were unacceptable because of either poor shimming conditions or contamination from neighboring fat. Spectra in three of five patients with abscess had lactate, amino acids (including valine, alanine, and leucine), and acetate peaks; one of the three spectra had an additional peak of succinate. In one patient with abscess treated by antibiotics, only lactate and lipid peaks were detected. Spectra for four of seven patients with cystic or necrotic tumors showed only lactate peaks. Lactate and lipids were found in three patients with tumors. Hyperintensity was seen in all the pyogenic abscess cavities and hypointensity in all the cystic and necrotic tumors on diffusion-weighted images. CONCLUSION: (1)H-MRS and diffusion-weighted imaging are useful for differentiating brain abscess from brain tumor, but the latter requires less time and is more accurate than is (1)H-MRS. (1)H-MRS is probably more limited in cases of smaller peripheral lesions, skull base lesions, and treated abscesses. 相似文献
996.
997.
目的探讨早产儿鼻饲胃管长度的最佳体表测量方法,减少喂养不耐受及并发症的发生。方法将118例鼻饲早产儿随机分为对照组(60例)和观察组(58例),对照组胃管置入长度采用"耳垂-鼻尖-剑突"测量法,观察组采用"眉弓-剑突"测量法,比较两组呕吐、胃潴留及胃出血发生率。结果对照组呕吐、胃潴留及胃出血发生率显著高于观察组(P0.05,P0.01)。结论采用"眉弓-剑突"测量早产儿胃管置入长度,可使胃管正好到达胃内又不至于在胃内盘曲,可减少呕吐、胃潴留等喂养不耐受及胃出血等并发症的发生。 相似文献
998.
Serum carcinoembryonic antigen (CEA) levels, elevated in a subgroup of patients with colorectal cancer (CRC) at presentation, are serially followed as part of recommended surveillance after initial resection. The value of following serial CEA levels in patients who initially present with less than or normal levels of CEA (nonsecretors) is controversial. This study sought to determine the use of follow-up CEA levels in nonsecretors. A retrospective review was performed of patients with resected Stage I, II, and III CRC. We excluded patients who did not have a pretreatment CEA level, at least two follow-up CEA levels, or in whom CEA levels did not normalize after resection. The patients were grouped by initial CEA values: CEA 5 ng/mL or less (nonsecretors) and CEA 5 + ng/mL: (secretors). We identified 186 patients with CRC; 146 were initial nonsecretors. We identified 22 patients with recurrent colorectal cancer; 6 were secretors and 16 patients were nonsecretors. In the secretors group, CEA was elevated with recurrence in four (66%) of the patients. In the nonsecretors, CEA was elevated with recurrence in eight (50%) of the patients. In summary, many recurrences of CRC are marked by an elevation of CEA regardless of whether the patients initially presented as secretors or nonsecretors. 相似文献
999.
1000.
BACKGROUND: Bile leakage remains a major postoperative complication after liver resection. Bile leakage after hepatectomy for liver neoplasms has been well studied. However, the risk factors and management of this complication after liver resection for intrahepatic lithiasis has not been investigated. METHODS: From January 1992 to June 2004, 312 consecutive patients with intrahepatic lithiasis underwent hepatic resections Sun Yet-san University. Perioperative risk factors pertaining to the development of bile leakage were identified using univariate and multivariate analysis. The management and outcome of these patients with bile leakage were evaluated. RESULTS: Bile leakage developed in 23 (7.4%) of 312 patients. The multivariate logistic regression analysis identified that left hepatectomy (P=.024, odds ratio [OR]=3.695, 95% confidence interval [CI]: 1.185 to 11.517) and the period greater than 1 month between operative time and the latest acute cholangitis attack (P=.02, OR=4.144, 95% CI: 1.248 to 13.757) were the independent risk factors for development of bile leakage after hepatectomy for hepatolithiasis. The septic complications were higher in the patients with bile leakage than in those without bile leakage (ie, wound infection: 56.5% vs 13.5%, P=.001; subphrenic abscess: 21.7% vs 4.8%, P=.01; septicemia: 8.7% vs 0.7%, P=.029). Percutaneous drainage or combined endoscopic naso-biliary drainage was the first choice of treatment for bile leakage; 20 (87.0%) of 23 patients were treated by this method. One patient underwent re-operation for diffuse peritonitis due to withdrawal of T tube inadvertently at postoperative day 1. Two patients with bile leakage were re-operated due to uncontrollable hemobilia at postoperative day 5 and 12, respectively. CONCLUSIONS: Patients who underwent hepatectomy at the period less than 1 month after the latest attack of acute cholangitis carry high risk for the development of bile leakage. Preoperative cholangiography to identify the aberrant hepatic duct for high risk patients and avoidance of hepatectomy at the acute phase of cholangitis are of critical importance to prevent bile leakage after hepatectomy. Percutaneous drainage is the primary and effective treatment for bile leakage. 相似文献