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81.
目的观察丁酸钠对结肠肿瘤细胞HT-29葡萄糖转运蛋白(GLUT1~GLUT5)表达的影响以及丁酸钠和不同浓度葡萄糖对bax和bcl-x/l表达的影响,探讨丁酸钠诱导肿瘤细胞凋亡的可能机制。方法2005年4月至12月在武汉大学人民医院应用逆转录-聚合酶链反应(RT-PCR)检测GLUT1~GLUT5mRNA的表达情况。免疫细胞化学法检测bax和bcl-x/l的表达。原位切口末端标记法(Tunel)检测细胞凋亡。结果丁酸钠明显抑制GLUT1和bcl-x/l表达并诱导肿瘤细胞凋亡,但对GLUT2、GLUT3、GLUT5和bax表达影响不大,GLUT4则未被检测出。丁酸钠干预条件下,葡萄糖浓度增加可以明显增加bcl-x/l的表达并降低丁酸钠诱导的细胞凋亡。无丁酸钠干预条件下,葡萄糖浓度变化对细胞凋亡影响很小。结论在HT-29细胞中,丁酸钠能明显降低GLUT1的表达。降低GLUT1的表达与丁酸钠诱导细胞凋亡作用密切相关。  相似文献   
82.
BACKGROUND: At present, there is still lack of effective drugs for chronic spinal cord injury, whereas it is found recently that estrogen has a neuroprotective effect on brain and spinal cord injuries. OBJECTIVE: To observe the effect of estrogen on the apoptosis of nerve cells after gradual chronic spinal cord injury in ovariectomized rats. DESIGN: A randomized controlled animal trial. SETTING: Institute of Orthopaedics, the Second Hospital of Lanzhou University. MATERIALS: Sixty-five female Wistar rats of common degree, weighing 220–250 g, were provided by the experimental animal center of Lanzhou University. The rats were randomly divided into sham-operated group (n =5), estrogen-treated group (n =30) and saline control group (n =30), and the latter two groups were observed at 1, 3, 7, 14, 28 and 60 days respectively, and 5 rats for each time point. METHODS: All the rats were treated with bilateral oophorectomy 2 weeks before the experiment. T10 vertebral lamina was revolved into using plastic screw. The spinal canal impingement was not induced initially. After that, the original incision was opened to expose the screw every 7–10 days. MAIN OUTCOME MEASURES: The apoptosis and Caspase-3 positive cells in the damaged spinal cord were detected using terminal deoxynucleotidal transferase-mediated dUTP-biotin nick end labeling (TUNEL) method and Caspase-3 immunohistochemical staining at 1, 3, 7, 14, 28 and 60 days after chronic spinal cord injury respectively. RESULTS: Totally 65 rats were used, and the deleted ones during the experiment were supplemented by others. Changes of Caspase-3 expression after spinal cord injury: In the sham-operated group, only a small amount of Caspase-3 proteins were observed in the rat spinal cord, mainly located in motor neurons of spinal cord anterior horn. In the estrogen-treated group and saline control group, positive cells expressed occasionally at 1 day postoperatively, began to increase obviously at 7 days after injury, strongly expressed at 14 and 28 days, but decreased at 60 days, mainly located in the neurons of spinal cord gray matter anterior horn, and they expressed fewer in the motor neurons and white matter of ventral horn, and there were obvious differences between the estrogen-treated group and saline control group at 7, 14, 28 and 60 days (P < 0.05). CONCLUSION: Estrogen can reduce the apoptosis of nerve cells and promote the recovery of neurological function following gradual chronic spinal cord injury.  相似文献   
83.
影响飞行员掩饰性心理家庭多因素分析   总被引:1,自引:1,他引:0  
目的 探讨飞行员夫妻双方掩饰性与心理健康及婚姻质量的关系.方法 采用症状自评量表、艾森克个性问卷的掩饰分量表和Olson婚姻质量问卷对288名空军飞行员夫妻双方进行评定,采用SPSS 15.0进行相关分析、回归分析.结果 发现飞行员以及妻子的掩饰特质与自身的心理健康9个因子:躯体化、强迫症状、人际关系敏感、焦虑、抑郁、敌对、恐怖、偏执、精神病性具有显著负相关性,前者相关系数在-0.219~-0.306之间,后者在-0.127~-0.391之间.飞行员以及妻子的掩饰特质与自身婚姻质量的12因子中的6(相关系数0.151~0.232)、7(相关系数0.123~0.309)项有显著正相关性;飞行员以及妻子的掩饰特质与对方的婚姻质量各有4项存在显著相关性,前者相关系数在0.127~0.251之间,后者在0.129~0.203之间.多因素分析揭示,对丈夫掩饰特质贡献最大的因素依次为妻子的焦虑情绪、妻子的恐怖情绪、丈夫的敌对情绪、妻子的婚姻满意度、丈夫的角色平等性;对妻子掩饰特质贡献最大的因素依次为妻子的敌对情绪、经济安排、性格相客性,丈夫的性生活、与亲友关系等.结论 开展飞行员心理健康教育,进行婚姻家庭心理咨询时,提高夫妻双方的掩饰性是非常有必要的.  相似文献   
84.
The distinction between seminoma and embryonal carcinoma based on morphology alone can sometimes be problematic, requiring the use of immunohistochemistry to facilitate diagnosis. D2-40 is a monoclonal antibody that reacts with an oncofetal antigen expressed by fetal germ cells and testicular germ cell tumors. The diagnostic value of D2-40 immunohistochemistry in distinguishing seminoma from embryonal carcinoma has not been determined. D2-40 immunoreactivity was evaluated in a series of testicular germ cell tumors and compared with that of KIT (CD117) and CD30, to assess the relative utility of this marker in discriminating between seminoma and embryonal carcinoma. Forty testicular germ cell neoplasms were examined, which included 19 seminomas, three embryonal carcinomas, three teratomas, one yolk sac tumor, and 14 mixed germ cell tumors. The 14 cases of mixed germ cell tumors contained components of seminoma (n=7), embryonal carcinoma (n=11), teratoma (n=10), yolk sac tumor (n=2), and choriocarcinoma (n=1). All cases of pure seminoma and the seminomatous components of mixed germ cell tumors exhibited positive immunoreactivity for D2-40. Focal positivity for D2-40 was also observed in 29% of the embryonal carcinoma samples. D2-40 immunoreactivity in seminomas was characterized by diffuse membrane staining, whereas for embryonal carcinomas, staining was focal and distributed along the apical surfaces of the neoplastic cells. Immunohistochemical staining for KIT was observed in 92% of the seminoma samples and in none of the embryonal carcinomas. Conversely, CD30 expression was identified in 93% of the embryonal carcinoma samples and in none of the seminomas. Other germ cell components showed no immunoreactivity for D2-40, KIT, or CD30. KIT and CD30 are effective immunohistochemical markers in separating seminoma from embryonal carcinoma. Although a highly sensitive marker for seminomas, D2-40 positivity was also observed in a subset of embryonal carcinomas, thus limiting the utility of this antibody for discriminating between these two malignancies.  相似文献   
85.
催化光度法测定灵芝中微量锌   总被引:1,自引:0,他引:1  
目的 研究催化光度法测定灵芝中微量锌。 方法 在非离子表面活性剂 Tween- 80存在下 ,于 p H9.5 0 NH3- NH4 Cl缓冲溶液中 ,Hg( )催化加速 Zn( )与 meso- 4 (4 -甲基 ,3-磺基苯基 )卟啉 (TTPS4 )的显色反应。 结果  Zn( )与 TTPS4 、Tween- 80形成很稳定的三元配合物 ,其ε=3.86× 10 5,Zn( )浓度在 0 .0 0 5~ 0 .10μg/ m L,符合比尔定律 ,检出限为 0 .0 0 1μg/ m L。 结论  Tween- 80对 Zn( )与 TTPS4 显色有增敏 ,而 Hg( )催化加速 Zn( )与 TTPS4 显色反应 ,应用本法可直接测定灵芝中的微量锌  相似文献   
86.
柯萨奇病毒诱发实验性多发性肌炎的初步研究   总被引:4,自引:0,他引:4  
分别用不同量的柯萨奇病毒B1、2、3感染和兔肌匀浆加完全弗氏佐剂免疫正常豚鼠;拟建立多发性肌炎模型。结果发现:0.1ml毒力为10-5TCID50柯萨奇病毒B1感染豚鼠组,3周后出现多发性肌炎症状。肌酶谱异常与其它组有明显差异,病理检查证实为多发性肌炎改变。单纯兔肌匀浆免疫对照组未发病。提示柯萨奇病毒B1感染及感染的病毒量与多发性肌炎的发病相关  相似文献   
87.
One hundred and twenty-one patients who had received a renal allograft between 4 months and 21 years previously (mean +/- SD, 71 +/- 62 months) were studied. Seventy-two patients were conventionally immunosuppressed with azathioprine and prednisolone, and 36 had been exposed to the current regime of cyclosporine, azathioprine, and prednisolone. Forty-five patients had viral warts, of whom 20 had more than 10 warts. The presence of viral warts was significantly associated with pale skin type, excess sun exposure, and with duration of allograft. Viral warts were significantly more common in those on conventional immunosuppressive therapy, but this could be solely a reflection of the difference in duration of transplant between the 2 groups. Twelve patients were found to have developed dysplastic or neoplastic skin lesions since transplantation. The incidence of dysplasia increased with increasing age and was significantly associated with pale skin type, excess sun exposure, and duration of allograft. Despite the shorter duration of treatment in those on the new treatment regime, there was no difference between the 2 groups in the proportion of patients with dysplastic skin lesions. Immunosuppression-related skin disease may be a significant problem in allograft recipients in this country, and we suspect that patients taking cyclosporine will have similar problems to those on conventional immunosuppressive drugs alone. Immunosuppressed patients should be advised to avoid sun exposure, to use sunscreens, and should be monitored carefully for the development of dysplastic lesions.  相似文献   
88.
Ninety-four Olmsted County, Minnesota residents with temporal arteritis (TA) initially diagnosed between 1950 and 1985 (incidence cohort) were identified. The age- and sex-adjusted incidence of TA per 100,000 population age 50 years or older was 17.0 (95% confidence interval [CI] 13.6-20.5), with a marked increase in incidence with age and a threefold greater incidence in women (23.4, 95% CI 18.2-28.7) than in men (7.4, 95% CI 3.7-11.0). The previously described secular increase in TA incidence in Olmsted County women continued from 1970 through 1985, while TA incidence in men declined in this latter time period. Although the frequency of classic clinical manifestations of TA declined over time, the percentage of patients undergoing biopsy who have positive specimens remained relatively constant (women 41%, men 26%). The incidence rate of temporal artery biopsy also increased for women during this period, but declined for men, suggesting that the differing trends in TA incidence by sex may be partially attributable to a detection bias. Future research in TA etiology and epidemiology should focus on possible causal factors linked to the differential TA incidence by sex.  相似文献   
89.
(席思川)(车东媛)(张婉蓉)TheInhibitoryEffectofRadixSalviaeMiltiorrhizaeonHypoxicStructuralRemodelingofIntra-acinarPulmonaryArteries¥XISi-c...  相似文献   
90.
目的:比较肥胖和非肥胖患者经阴道子宫全切除术的手术结局。方法:因子宫良性病变行子宫全切除者,BM I≥30 kg/m2者为研究组,BM I<30 kg/m2者为对照组。比较两组的出血量、手术时间、排气时间、住院时间、发热率、子宫重量及其他并发症的发生情况。结果:研究组和对照组出血量分别为(184.6±82.7)m l及(179.8±78.2)m l,出血量超过500 m l而需要输血者研究组及对照组分别为4.8%(2例)及4.1%(8例),手术时间分别为(87.4±23.6)m in及(85.9±25.1)m in,排气时间分别为(16.4±3.6)h及(17.1±4.2)h,住院时间分别为(5.7±1.2)天及(5.5±1.1)天,发热率分别为7.1%(3例)及6.1%(12例),子宫重量分别为(261.5±52.8)g及(258.3±48.6)g(P>0.05)。结论:经阴道子宫全切除术可安全应用于肥胖患者。  相似文献   
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