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101.
102.
体外模拟二氧化碳人工气腹对宫颈癌细胞生长的影响 总被引:1,自引:0,他引:1
目的 观察二氧化碳(CO2)人工气腹对宫颈癌细胞生长的影响,探讨其与乏氧的关系。方法 2005-10—2006-03华中科技大学同济医学院附属协和医院通过裸鼠右下腹腔注射宫颈癌细胞,注射宫颈癌细胞株(Hela)数量:4×10^9/L:将注射后40只裸鼠随机分成4组,每组10只:阴性对照组(常氧组):仅给予右下腹腔注射宫颈癌细胞;CO2气腹模拟环境按CO2灌注压分3组:CO2灌注压4mmHg(1mmHg=0.133kPa)组,CO2灌注压10mmHg组,CO2灌注压16mmHg组.4周后观察裸鼠体重改变、切除瘤灶称瘤重、瘤体标本用免疫组化测定增殖细胞核抗原(PCNA)、Western-blot方法检测瘤体的缺氧诱导因子-1α(HIF-1α)表达.结果 与阴性对照组比较,CO2气腹各组裸鼠体重下降明显,而瘤体重量增加相对显著,并随着CO2灌注压的增高这种趋势更为显著(P〈0.05);CO2气腹各组裸鼠PCNA表达显著高于阴性对照组(P〈0.01);CO2气腹各组裸鼠HIF-1α蛋白的表达与阴性对照组比较明显增加,差异有统计学意义(P〈0.01).结论 与阴性对照组比较,CO2人工气腹环境可促进宫颈癌细胞生长,其机制可能与HIF-1α激活了PCNA表达,促进了细胞增殖有关。 相似文献
103.
BACKGROUND AND PURPOSE: Hypoxia, a frequent characteristic of cervical cancer, is associated with reduced sensitivity to irradiation and thus may be a source of radiotherapy failure. This study was planned to test the hypothesis, that inhalation of oxygen during radiotherapy may increase the radiation effect on the tumor and improve loco-regional control and overall survival. MATERIAL AND METHODS: From 1963 to 1965, a consecutive series of 208 patients with cervical cancer stage II/III who were to be treated by external irradiation plus radium inserts, were included in this study. They were randomly assigned to either receive oxygen inhalations during the radiotherapy sessions or just breathing air. Due to technical reasons the oxygen group was divided. For the first 10 months, they did receive oxygen during the radium inserts only, the last 13 months during all radiotherapy sessions. RESULTS: After median 33 years follow-up, there are no differences in overall survival, cancer-specific survival or loco-regional control. Subgroup analysis shows significantly improved loco-regional control in the stage IIB patients, with squamous cell carcinoma who received oxygen during all radiotherapy sessions. This improvement was especially pronounced among the patients who also received blood transfusions. CONCLUSIONS: There was no influence of normobaric oxygen treatment on the overall outcome to radiotherapy in patients with stage II cervical cancer, but subgroup analyses support the hypothesis that there is tumor areas of hypoxia-based radioresistance that may be counteracted by oxygen administration. 相似文献
104.
Oncogenic aberrations in the p53 pathway are associated with a high S phase fraction and poor patient survival in B-cell Non-Hodgkin's lymphoma 总被引:7,自引:0,他引:7
Stokke T Galteland E Holte H Smedshammer L Suo Z Smeland EB Børresen-Dale AL DeAngelis P Steen HB 《International journal of cancer. Journal international du cancer》2000,89(4):313-324
The implications of aberrations in the p53 pathway for induction of apoptosis and regulation of S phase entry, and for patient survival, were investigated in 83 B-cell Non-Hodgkin's lymphomas. Eight cases had missense mutations in exons 5, 7, 8 and 9 as revealed by constant denaturant gel electrophoresis and sequencing. Fifteen cases had lost 1 TP53 allele as revealed by fluorescent in situ hybridization and comparative genomic hybridization. Ten cases expressed high levels of p53 as assessed by immunoblotting and immunohistochemistry. S phase fractions were higher, apoptotic fractions were the same and survival times were shorter in all aberration groups compared with the cases with no TP53/p53 aberrations. Since many tumors had more than one TP53/p53 aberration, the tumors were divided into groups with the following characteristics: no TP53/p53 aberrations; loss of one TP53 allele only (9 cases), TP53 point mutation (8 cases), high-level p53 expression and no TP53 mutation (3 cases). Tumors from the 3 latter groups had higher median S phase fractions (5%, 7.6%, and 5%, respectively, p<0.02) than the cases without any aberrations (1.1%), and survival time for these patients was much shorter (relative risks of 5.9, 8.9, and 6.6, respectively, p<0.003). Apoptotic fractions were similar in all these groups (p=0.09). Multivariate analysis showed that the presence of TP53/p53 aberrations is a strong and independent prognostic parameter in B-cell Non-Hodgkin's lymphoma. 相似文献
105.
目的 探讨体育锻炼对主观幸福感的影响,为提高军队离退休人员生活质量提供建议.方法 采用整群抽样的方法 ,分别采用纽芬兰纪念大学主观幸福感指数量表和课题组编制的军队离退休人员参加体育活动状况调查表,对183名军队离退休人员进行调查,并采取4种不同的体育锻炼形式对88名被试进行为期3个月的培训,分析体育锻炼前后主观幸福感的变化.结果 不同体育锻炼水平群体之间主观幸福感有显著差异,通过每天1 h的集体体育锻炼,可以显著提高军队离退休人员的主观幸福感水平.结论 体育锻炼对军队离退休人员主观幸福感有显著影响,通过集体体育锻炼进一步提高军队离退休人员的生活质量. 相似文献
106.
Shiang Suo Huang Tadahiko Mashino Masataka Mochizuki Long Y Chiang Lan Hui Chih Hung Ming Hsieh Chen Ming Teng Kensuke Okuda Takasi Hirota Ming Cheng Tsai 《Pharmacology》2002,64(2):91-97
The effects of hexasulfobutylated C(60) (FC(4)S) and monomalonic acid C(60) (MMA C(60)), the fullerene C(60) derivatives, on isolated endothelium-containing or endothelium-denuded aorta of guinea pig were studied pharmacologically in vitro. In the endothelium-containing preparation of the aortic rings, phenylephrine (PHE) elicited contracture and acetylcholine (ACh) elicited a relaxing effect on the PHE-precontracted preparation. In the PHE-precontracted preparation, MMA C(60) (10 micromol/l) did not elicit a relaxing effect on the PHE-precontracted preparation. However, MMA C(60) (10 micromol/l) significantly reduced the maximum response of the relaxation elicited by ACh. FC(4)S itself significantly relaxed the PHE-precontracted aortic rings. ACh-induced relaxation in PHE-precontracted endothelium-containing strips of the aortic rings was significantly potentiated if pretreated with FC(4)S (10 micromol/l). In the denuded aortic rings, FC(4)S did not elicit the relaxing effect in the PHE-precontracted preparation. The relaxing effect of FC(4)S on the PHE-precontracted preparation was not altered when superoxide dismutase (250 units/ml) was pretreated. However, the relaxing effect was reduced when N(G)-nitro-L-arginine methyl ester (L-NAME, 1 mmol/l) or methylene blue (1 micromol/l) was pretreated. These results demonstrated that the vasorelaxation effect of FC(4)S on the PHE-precontracted aortic ring is partly dependent on the release of nitric oxide (NO) or an NO-derived substance from the vascular endothelium. 相似文献
107.
反相高效液相色谱法测定黄芪蛰虫口服液中黄芪甲苷含量 总被引:6,自引:0,他引:6
目的 :测定黄芪蛰虫口服液中黄芪甲苷的含量。方法 :采用反相高效液相色谱法 ,流动相为乙腈 水 磷酸 (34∶6 6∶0 .1) ,检测波长为 2 0 3nm。结果 :线性方程为H =4 6 .98C - 1.782 ,r =0 .9996 ,黄芪甲苷在 5 0 .30~ 5 0 3.0 μg·ml-1范围内线性关系良好 ,平均回收率为 97.0 5 % ,RSD为 1.99% (n =5 )。结论 :建立的含量测定方法简便 ,准确。 相似文献
108.
109.
BACKGROUND AND PURPOSE: Tuberculosis (TB) in prison is a serious public health problem that is fueled by overcrowding, poor nutrition and unsatisfactory medical services. To evaluate the magnitude of the TB epidemic in Taiwanese prisons, we analyzed the results of a screening program for TB among inmates. METHODS: A mass radiography screening was performed in 24 prisons and five jails from July 1998 through June 1999. The National TB Register was notified and treatment with a rifampin-based short-course anti-TB regimen was given for all cases identified in the screening. The outcome of treatment of TB inmates was determined from records of the National TB Register. RESULTS: A total of 51,496 inmates were screened. Pulmonary TB was diagnosed in 107 (258.7 per 100,000 population) inmates. Among them, 88 (82.2%) were newly diagnosed TB patients, 12 (11.2%) had a history of anti-TB treatment and were re-treated after screening, and seven (6.6%) had previously diagnosed TB and were receiving treatment at the time of screening. Of the 107 inmates with TB, 86 (80.4%) completed treatment, 17 (15.9%) were lost to follow-up due to release from prison, and four (3.7%) died (three of TB). During a mean of 26.2 +/- 4.4 months (range, 19.7-39.0 mo) post-registration follow-up, three patients who had completed treatment relapsed. CONCLUSIONS: The high prevalence of TB in prisons indicates that prison administrators and the national TB program in Taiwan need to strengthen their activity to control this disease. The establishment of a surveillance section of the national TB program to systematically collect data on TB in prisons may facilitate efforts to monitor and control TB both in prisons and the general population. Our findings also indicate that TB control in prisons should give top priority to improving mycobacteriology laboratory services to ensure the quality of sputum examinations. 相似文献
110.
目的:观察不同剂量的解毒通络方对脑缺血损伤后大鼠学习记忆能力的影响。方法:实验于2005-06/07在北京中医药大学病理实验室和中国医学科学院药用植物研究所神经药理试验室完成。选择健康清洁级SD大鼠120只,按随机数字表法选择20只作为正常对照组,其余大鼠采用反复夹闭双侧颈总动脉结合硝普钠降压法复制SD大鼠拟血管性痴呆模型。造模后的大鼠随机分为模型组、脑心通组和解毒通络方1.85g/kg,3.7g/kg和7.4g/kg组,每组各20只。脑心通组和解毒通络方1.85g/kg,3.7g/kg和7.4g/kg组分别灌胃给予0.084g/mL的脑心通胶囊混悬液、1.85g/kg,3.7g/kg和7.4g/kg的解毒通络方(由栀子、黄芪、丹参等组成)稀释液5.0mL/kg。正常组与模型组同样按照5.0mL/kg的体积每日用纯净水灌胃。连续给药4周后进行Morris水迷宫测试,通过变换平台位置对大鼠空间定向能力(探索阶段)及再学习能力(再学习阶段)进行评价,比较潜伏期和平均速度。结果:进入结果分析6组大鼠共92只。①在探索阶段,模型组的潜伏期时间显著长于正常对照组(P<0.01),解毒通络方3.7g/kg和7.4g/kg组与模型组比较潜伏期显著缩短(P<0.01);模型组与正常对照组比较平均速度显著降低(P<0.01),解毒通络方1.85g/kg组与模型组比较平均速度显著提高(P<0.05)。②在再学习阶段,模型组潜伏期与正常对照组比较显著延长(P<0.01),解毒通络方3.7g/kg和7.4g/kg组则较模型组显著缩短(P<0.05);模型组平均速度显著低于正常组(P<0.01),同时解毒通络方3个剂量组与模型组比较平均速度均有显著提高(P<0.05)。结论:解毒通络方3.7g/kg,7.4g/kg组的疗效比较明显,在大鼠寻找平台平均潜伏期的缩短和平均速度的提高上都表现出显著的药物治疗作用;而1.85g/kg组的疗效则主要体现在提高平均速度上。提示解毒通络方能够明显改善血管性痴呆大鼠的空间探索与定向能力,提高其学习与再学习能力。 相似文献