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61.
Xu J  Xia X  Leung AW  Xiang J  Jiang Y  Yu H  Bai D  Li X  Xu C 《Ultrasonics》2011,51(4):480-484
Sonodynamic therapy with pyropheophorbide-a methyl ester (MPPa) presents a promising aspect in treating liver cancer. The present study aims to investigate the mitochondrial damage of liver cancer cells induced by MPPa-mediated sonodynamic action. Mouse hepatoma cell line H22 cells were incubated with MPPa (2 μM) for 20 h and then exposed to ultrasound with an intensity of 0.97 W/cm2 for 8 s. Cytotoxicity was investigated 24 h after sonodynamic action using MTT assay and light microscopy. Mitochondrial membrane potential (ΔΨm) was analyzed using flow cytometry with rhodamine 123 staining and ultrastructural changes were observed using transmission electron microscopy (TEM).The cytotoxicity of MPPa-mediated SDT on H22 cell line was 73.00 ± 3.42%, greater than ultrasound treatment alone (28.12 ± 5.19%) significantly while MPPa treatment alone had no significant effect on H22 cells. Moreover, after MPPa-mediated SDT cancer cells showed swollen mitochondria under TEM and a significant collapse of mitochondrial membrane potential. Our findings demonstrated that MPPa-mediated SDT could remarkably induce cell death of H22 cells, and highlighted that mitochondrial damage might be an important cause of cell death induced by MPPa-mediated SDT.  相似文献   
62.
Amanitins, highly toxic cyclopeptides isolated from various Amanita species, are the most potent poisons accounting for the hazardous effects on intestinal epithelium cells and hepatocytes, and probably the sole cause of fatal human poisoning.  相似文献   
63.
硒酸脂多糖具有硒和多糖两者特殊作用,它治疗原发性肝癌有肯定的疗效。  相似文献   
64.
Despite CYP induction in vitro in precision-cut liver slices (LS) is well documented, there are no standardised assays for determining CYP activity as a major end-point. In this paper, short-term assays with intact and homogenised LS from male and female rats were directly compared. We obtained similar results for 7-ethoxycoumarine O-deethylation (ECOD) with LS from both sexes: higher basal activities were measured in LS homogenate, whereas slightly stronger induction by BNF was found with intact LS. CYP3A-dependent basal and dexamethasone (Dex)-induced 2β-, 15β- and 6β-testosterone hydroxylation (TH) rates were higher in both intact and homogenised LS from male compared to female rats. CYP3A induction in vitro could likewise be detected in intact and homogenised LS preferentially by determining 2β- and 15β-TH, with higher induction factors observed in LS from females. 6β-TH seems to be less inducible in intact LS of males. In vivo pretreatment of liver donors with BNF and Dex did not substantially disturb the subsequent in vitro induction of ECOD and TH, respectively.  相似文献   
65.
A simple high‐performance liquid chromatography method has been developed for the determination of formaldehyde in human tissue. FA Formaldehyde was derivatized with 2,4‐dinitrophenylhydrazine. It was extracted from human tissue with ethyl acetate by liquid–liquid extraction and analyzed by high‐performance liquid chromatography. The calibration curve was linear in the concentration range of 5.0–200 μg/mL. Intra‐ and interday precision values for formaldehyde in tissue were <6.9%, and accuracy (relative error) was better than 6.5%. The extraction recoveries of formaldehyde from human tissue were between 88 and 98%. The limits of detection and quantification of formaldehyde were 1.5 and 5.0 μg/mL, respectively. Also, this assay was applied to liver samples taken from a biopsy material.  相似文献   
66.
Liver iron concentration was determined in 28 patients by magnetic resonance imaging using the method of Gandon et al. (Non-invasive assessment of hepatic iron stores by MRI. Lancet 2004;363:357-362). The result showed a significant correlation with blood plasma ferritin content (Spearman's r=.66; P<.001) and a slightly improving correlation coefficient when limited to those patients not known to have inflammation (r=.82; n=17; P<.001). Zooming in on patients with hematologic disease also had a beneficial effect on the correlation between liver iron content and plasma ferritin level (r=.79; n=13; P=.001). It is concluded that in patients without inflammation and in patients with hematologic disease, the content of ferritin in blood is a better predictor of liver iron content than in other patient categories.  相似文献   
67.
研究了低(1mg/kg/d)、中(5mg/kg/d)、高(25mg/kg/d)三个剂量组全氟辛酸(Perfluorooctanoic acid,PFOA)致小鼠肝脏脂质过氧化损伤的作用.结果发现,PFOA能抑制小鼠体重的增长,对肝组织造成一定的脂质过氧化损伤.各组小鼠出现不同程度的体重增长缓慢甚至减轻,中、高剂量组出现明显的减轻(P<0.01);低、中、高剂量组肝脏系数,均明显高于对照组(P<0.01);与对照组相比,各剂量组的肝组织中MDA、NO及LDH含量明显增高,SOD、SDH及GSH-Px活性均明显降低(P<0.05).  相似文献   
68.
Laser excited atomic fluorescence spectrometry (LEAFS) with a N2-laser pumped dye laser with a Shimadzu GFA-4A graphite furnace is used to determine thallium in solid samples of bovine liver and tomato leaves. The linear range for thallium under the studied conditions is 0–50 pg. The instrumental LEAFS detection limit for thallium was 100 fg. Solid samples from National Institute of Standards and Technology were analyzed by this method. The content of thallium in bovine liver and tomato leaves was 0.059 and 0.055 μg/g with relative standard deviation of 12.5% and 15.8% respectively; the results obtained are within the reported limit.  相似文献   
69.
张英杰  彭明霞  沈朝敏  张玉惠  张国强 《应用数学》2013,35(20):1820-18,221,863
目的:评价带蒂脾段后腹膜固定术治疗门静脉高压症的临床应用可行性及疗效。方法选择肝炎后肝硬化、门静脉高压症、脾功能亢进患者44例,其中行带蒂脾段后腹膜固定术24例(观察组),行全脾切除术20例(对照组)。比较两组患者手术时间、术中出血量、术后住院时间及术后并发症发生情况,以及周围血象(白细胞计数、血小板计数)、免疫功能指标(CD4、CD8、CD4/CD8)等。结果观察组手术时间明显短于对照组、术后并发症发生率明显低于对照组(均P<0.05);观察组术后10d、术后2个月白细胞计数均明显低于对照组(均P<0.05),术后3、10d及术后2个月血小板计数均明显低于对照组(均P<0.05);观察组术后10d CD4比例及IgG含量均明显高于对照组(均P<0.05),术后2个月CD4比例、CD4/CD8及IgA、IgM含量均明显高于对照组(均P<0.05),CD8比例明显低于对照组(P<0.05)。结论带蒂脾段后腹膜固定手术是一种较好的保脾手术方式,保留了脾脏的部分或大部分功能,避免了术后门静脉血栓的发生,并且远期具有分流作用,技术上是安全可行的。  相似文献   
70.
The matrix solid-phase dispersion (MSPD) was applied for extracting seven sulfonamides (SAs) in liver samples. The separation and determination were carried out by high-performance liquid chromatography. The analytes were derivated with fluorescamine and detected with fluorescence detector. The types of dispersion adsorbents for MSPD were examined and the highest recovery was obtained when the diatomaceous earth was used as the dispersion adsorbent and the mass ratio of dispersion adsorbent to sample was 3:1. The acetone was used as the elution solvent. Under the optimal conditions, the linear range for determining the SAs in liver samples was 5.0-1000.0 ng/g. The porcine, chicken and cattle liver samples were analyzed and the average recoveries of seven SAs were higher than 84.6%.  相似文献   
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