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71.
目的 观察表达IL-18的溶瘤腺病毒(ZD55-IL18)对裸鼠肾癌移植瘤生长及血管形成的抑制作用.方法 荷肾癌裸鼠随机分4组,每组8只.瘤体内注射ZD55-IL18、溶瘤腺病毒ZD55-EGFP、表达IL-18的增殖缺陷腺病毒Ad-IL18及PBS,每次注射病毒7×108PFU/只,连续注射3 d.注射后第7天,每组处死3只取肿瘤组织,免疫组织化学检测肿瘤E1A、IL-18、CD34、VEGF表达及凋亡.第50天时处死动物测量肿瘤体积.结果 ZD55-IL18、ZD55-EGFP、Ad-IL18及生理盐水处理组肿瘤体积(mm3)分别为:299.7±52.9、536.8±90.3、570.3±99.0、766.1±145.8,ZD55-IL18与各组之间差异有统计学意义(P<0.01).Ad-IL18处理组肿瘤无E1A蛋白表达,ZD55-IL18处理组有大量E1A蛋白表达,表明病毒复制.ZD55-IL18处理组肿瘤IL-18表达及凋亡细胞阳性率均显著高于Ad-IL18处理组.ZD55-IL18处理组肿瘤CD34、VEGF表达均显著低于Ad-IL18处理组.结论 表达IL-18的溶瘤腺病毒ZD55-IL18比增殖缺陷腺病毒Ad-IL18具有更强的抑制肾癌生长及血管形成作用.  相似文献   
72.
目的 观察表达白细胞介素18(IL-18)基因的条件增殖腺病毒在肾癌Ketr-3细胞中的生物活性及其对Ketr-3细胞的杀伤作用.方法 通过荧光显微镜观察表达绿色荧光蛋白的条件增殖腺病毒(ZD55-EGFP)在肾癌Ketr-3细胞中的感染和增殖情况.分别将表达IL-18的条件增殖腺病毒(ZD55-IL-18)及表达IL-18的普通腺病毒(Ad-IL-18)感染人肾癌Ketr-3细胞系,通过Western blot法检测病毒E1A和IL-18蛋白的表达;免疫细胞化学染色检测IL-18抗原表达;TUNEL法检测Ketr-3细胞的凋亡情况;噻唑蓝(MTT)比色法检测Ketr-3细胞存活情况.结果 ZD55-EGFP能有效感染肾癌Ketr-3细胞并在其中大量增殖.Westem blot检测结果 发现ZD55-IL-18能在肿瘤细胞内表达E1 A并有效介导IL-18表达,在病毒感染Ketr-3细胞48 h后,ZD55-IL-18、Ad-IL-18处理组的IL-18蛋白表达量分别为255.6±3.1、118.7±2.90免疫组织化学检测显示ZD55-IL-18、Ad-IL-18处理组的IL-18抗原阳性率分别为(82.4±3.2)%和(23.4±1.9)%.TNUEL检测结果 显示ZD55-IL-18、Ad-IL-18处理组的细胞凋亡率分别为(52.2±3.5)%和(25.5±1.9)%.病毒感染4 d后,MTT检测结果 显示ZD55-IL-18、Ad-IL-18处理组细胞存活率分别为(32.6±2.3)%和(73.3±2.5)%,表明ZD55-IL-18对Ketr-3细胞有显著的杀伤作用.结论 ZD55-IL-18能在Kerr-3细胞中高效特异性表达IL-18基因并显示出良好的抗肿瘤作用.  相似文献   
73.
目的研究六味通脉胶囊对动脉硬化闭塞症(ASO)患者外周血白细胞介素-6(IL-6)和肿瘤坏死因子-α(TNF-α)含量变化及T细胞亚群的影响,并进一步探讨该复方中药抗ASO的作用机制。方法将93例符合入选标准的ASO患者,采用双盲双模拟研究方法,随机分为治疗组和对照组,从T细胞亚群(CD3+、CD4+、CD8+、CD4+/CD8+)I、L-6、TNF-α含量变化等方面进行前瞻性对比治疗研究。结果ASO患者存在免疫功能的低下,血液IL-6、TNF-α含量明显升高,与健康人比较有显著性差异(P<0.05或0.01)。经3个疗程的治疗后,2组患者的各观察指标均有不同程度的改善,与治疗前比较有显著性差异(P<0.05或0.01);治疗后治疗组与对照组比较,有显著性差异(P<0.05或0.01)。结论六味通脉胶囊能明显提高免疫功能,降低血液IL-6、TNF-α的含量。六味通脉胶囊对ASO患者的预后影响与提高免疫功能及降低血液IL-6、TNF-α的含量有关。  相似文献   
74.
目的探讨沙漠干热环境下猪腹部肠管火器伤后肝脏组织TNF-α的表达和肝功能的变化。方法沙漠干热环境组和常温环境组健康长白仔猪各42头随机等分为对照组和伤后1、2、4、8、12 h和24 h组,实验组建立腹部火器伤肠管穿透模型后,用免疫组化及图像分析法测定各组肝脏组织内TNF-α的表达,同时测定血清中AST水平。结果伤后各组肝组织TNF-α表达明显高于对照组,沙漠干热环境组于伤后2 h和8 h出现2个高峰;常温环境组于伤后2 h和12 h出现2个高峰。血清AST水平于伤后显著增高,并于伤后2 h出现第1个高峰,沙漠干热环境组和常温环境组分别于伤后8 h和12 h出现第2个高峰。结论沙漠干热环境下腹部肠管火器伤后肝脏TNF-α的表达增加并与AST的变化趋势一致,而且峰值较常温组提前出现,提示TNF-α在腹部肠管火器伤后肝损伤过程中可能起重要作用。  相似文献   
75.
目的探讨缺氧诱导因子-1α(HIF-1α)在ESWL致肾脏损伤中的作用及黄芪是否通过调节HIF-1α的表达而发挥对肾脏的保护作用。方法45只家兔随机分为对照组、ESWL损伤组和黄芪治疗组,每组15只,除对照组外,所有动物接受ESWL处理(18kV,1 500次)。黄芪治疗组家兔于冲击前3d至后2d,每天注射黄芪注射液2.0g/kg。2周后处死家兔,取肾脏HE染色观察肾组织形态学改变,免疫组织化学染色观察HIF-1α在肾脏中的表达。结果ESWL处理后肾小管上皮细胞肿胀、脱落,小管内可见大量管型,肾间质大量炎细胞浸润;黄芪治疗组以上病变显著减轻。ESWL损伤组HIF-1α显著表达于肾小管上皮细胞及间质,黄芪能够明显抑制HIF-1α的表达。结论HIF-1α参与了ESWL对肾脏的损伤,黄芪可能通过抑制HIF-1α的表达发挥对肾脏的保护作用。  相似文献   
76.
77.
Trisomy 18 is the second most common genetic defect after trisomy 21, almost 90% of which are due to additional chromosome from the mother. The parental origin of the additional chromosome can, if required, be determined by two methods: karyotyping, which takes several weeks; or, more recently, by polymerase chain reaction (PCR) which is often problematic. Fluorescent PCR of small tandem repeats (STRs) can determine the parental origin in the majority of cases within 5 h. Although the incidence of paternal origin is known for both trisomy 21 and trisomy 18, this technique can rapidly determine the parental origin in cases where there is insufficient samples to perform conventional tests. Determining parental origin by these methods may also have clinical significance in the diagnosis of chromosomal translocations or in the diagnosis of genetic disease using linkage analysis.  相似文献   
78.
Noninvasive techniques for the assessment of cardiac metabolism are important for the detection of potentially salvageable tissue in jeopardized areas of the myocardium. The correct identification of hibernating and stunned myocardium in patients with severely depressed cardiac function can have vital therapeutic consequences for the patient. Changes in myocardial fatty acid and glucose metabolism during acute and prolonged ischemia can be traced by positron-emitting or gamma-emitting radiopharmaceuticals. Alternatively,31P-labeled magnetic resonance spectroscopy can be used for the assessment of high-energy phosphate metabolism. It is not yet clear which modality will emerge as the most useful in the clinical setting. Positron emission tomography (PET) that uses combinations of flow tracers and metabolic tracers offers unique opportunities for quantification and high-resolution static and rapid dynamic studies. Currently, assessment of glucose metabolism with18F-fluorodeoxyglucose is regarded as the gold standard for myocardial viability and prediction of improvement of impaired contractile function after revascularization. However, preserved oxidative metabolism may be required for potential functional improvement, and therefore assessment of residual oxidative metabolism by11C-labeled acetate PET may prove to be more accurate than18F-fluorodeoxyglucose PET, which reflects both anaerobic and oxidative metabolism. Moreover, because fatty acids are metabolized only aerobically, they are excellent candidates for the clinical assessment of myocardial viability and prediction of functional improvement after revascularization. Especially derivatives of fatty acids that are not metabolized but accumulate in the myocyte are attractive for myocardial imaging. Examples are123I-beta-methyl-p-iodophenyl pentadecanoic acid and 15-(o-123I-phenyl)-pentadecanoic acid. These tracers can be detected by planar scintigraphy and single-photon emission computed tomography, which are more economical and widely available than PET. In addition, 511 keV collimators have been developed recently, making the detection of positron emitters by planar scintigraphy and single-photon emission computed tomography feasible. The experience with31P-labeled magnetic resonance spectroscopy in humans is still limited. With current magnetic resonance spectroscopic techniques, insufficient spatial resolution is achieved for clinical purposes, but the possibility of serial measurements to monitor rapid changes of phosphate-containing molecules in time makes magnetic resonance spectroscopy very valuable for the research of myocardial metabolism.  相似文献   
79.
The purpose of this study was to assess the feasibility of imaging of bladder cancer with fluorine-18 fluorodeoxyglucose positron emission tomography (FDG-PET) scanning. We studied 12 patients with histologically proven bladder cancer who had undergone surgical procedures and/or radiotherapy. Retrograde irrigation of the urinary bladder with 1000–3710 ml saline was performed during nine of the studies. Dynamic and static PET images were obtained, and standardized uptake value images were reconstructed. FDG-PET scanning was true-positive in eight patients (66.7%), but false-negative in four (33.3%). Of 20 organs with tumor mass lesions confirmed pathologically or clinically, 16 (80%) were detected by FDG-PET scanning. FDG-PET scanning detected all of 17 distant metastatic lesions and two of three proven regional lymph node metastases. FDG-PET was also capable of differentiating viable recurrent bladder cancer from radiation-induced alterations in two patients. In conclusion, these preliminary data indicate the feasibility of FDG-PET imaging in patients with bladder cancer, although a major remaining pitfall is intense FDG accumulation in the urine. Present address: Department of Radiology, National Defense Medical College, 3-2 Namiki, Tokorozawa 359, Japan  相似文献   
80.
Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET) imaging was performed in seven consecutive patients with primary hyperparathyroidism to preoperatively locate parathyroid adenomas. Foci of FDG accumulation corresponding to abnormal parathyroid tissue were observed in two out of nine surgically excised parathyroid adenomas. It was concluded that FDG PET imaging demonstrated a too low sensitivity for systematic preoperative detection and localization of parathyroid glands causing primary hyperparathyroidism.  相似文献   
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