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991.
The brains of 57 consecutive Chinese patients, aged 65 years or above, dying in a regional general hospital, the causes of death of whom were not primarily intracranial, were examined for parameters of degenerative brain disease--reduction in brain weight, ventricular enlargement, neurofibrillary tangles, senile plaques, granulovacuolar degenerations, and ischemic lesions. Semi-quantitative analysis of these morphological changes suggests that, though generally similar to those observed among Caucasians, they occurred much less frequently, and, as regards senile plaques, in smaller numbers. These observations suggest a lower prevalence of "senile" cerebral alterations in Chinese than in Caucasians. 相似文献
992.
Yang Hee Lee Ihn Rhan Lee Won Sick Won Chung Hee Park 《Archives of pharmacal research》1988,11(3):247-249
993.
A sensitive and simplified HPLC assay of fluconazol is described. The calibration curve of fluconazol in plasma ranging 0–10 μ g/ml was linear with the correlation coefficients of 0.9900. The limit of detection was 0.3 μ g/ml. The average recovery of the drug was 89.1±9.05%. After oral administration of single dose(150mg) of fluconazol in man, Cmax and Tmax were 3 μg/ml and 4hr., respectively. 相似文献
994.
Quantitation of protein adducts as a marker of genotoxic exposure: immunologic detection of benzo(a)pyrene -- globin adducts in mice 总被引:1,自引:0,他引:1
Immunologic methods have been developed for the determinationof benzo(a)pyrene (BP)-protein adducts and validated in animalstreated with (3H)BP. A previously developed antibody, 8E11,which recongnizes 7ß, 8-dihydroxy-9, 10-epoxy-7, 8,9, 10tetrahydrobenzo(a)pyrene (BPDE-I)-modified DNA or proteinas well as BPDE-I- tetraols, was used. The sensitivity of theassay was increased by enzymatic digestion of the modified proteinwith insoluble protease into peptides and amino acids beforeanalysis. In a competitive enzymelinked immunosorbent assay(ELISA) with digested BPDE-I-modified bovine serum albumin,50% inhibition occured at 400 fmol of adduct compared to 1450fmol for the nondigested albumin. Analysis of globin (Gb) isolatedfrom animals treated in vivo with 0.33 mg (3H)BP indicatedthat the ELISA could detect 90100% of the adducts determinedby radioactivity. Levels of adducts in lung and liver DNA andserum albumin were correlated with the levels of Gb adducts.Of the total radioactivity associated with hemoglobin, only10% was from Gb while {small tilde}80% was from the heme fractionand the remainder from free BP metabolites. Significant cross-reactivityof antibody 8E11 was found with several BP-diols and phenols,suggesting that the immunoassay will not only be specific forBPDE-I adducts but will also detect adducts of other BP metabolitesas well as other aromatic hydrocarbon diol epoxides. An immunoaffinitycolumn of antibody 8E11 coupled to Sepharose 4B was used toisolate modified peptides from the digested Gb. About 65% ofthe applied radioactivity was retained on the column. Between1 and 2 mg of non-modified digested Gb could be added to thesample without interfering with binding of adducts. Proteindigestion and immunoaffinity chromatography should be usefulfor the measurement of protein adducts in biomonitoring studies. 相似文献
995.
Buthionine sulfoximine-mediated depletion of glutathione in intracranial human glioma-derived xenografts 总被引:1,自引:0,他引:1
S X Skapek O M Colvin O W Griffith D R Groothuis E V Colapinto Y Lee J Hilton G B Elion D D Bigner H S Friedman 《Biochemical pharmacology》1988,37(22):4313-4317
D-54 MG, a human glioma-derived continuous cell line growing as subcutaneous or intracranial xenografts in athymic mice, was found to be sensitive to the effects of D,L-buthionine-(SR)-sulfoximine, a selective inhibitor of gamma-glutamylcysteine synthetase. Intraperitoneal administration of one dose of buthionine sulfoximine (BSO, 5 mmol/kg) resulted in depletion of total intracellular glutathione to 57 and 47% of control 12 hr, and 73 and 23% of control 24 hr, after BSO in subcutaneous and intracranial xenografts respectively. Concurrent measurement of total glutathione in the contralateral (non-tumor-containing) cerebral hemisphere in mice bearing intracranial D-54 xenografts demonstrated insignificant depletion of glutathione. Multiple doses of BSO, at 12-hr intervals, resulted in further depletion to 27% (s.c.) and 16.5% (i.c.) of control 12 hr following the final dose of BSO. Quantitative analysis of BSO delivery to xenograft and contralateral brain tissue revealed transfer constants, K1, of 15.8-24.1 x 10(-3) and 2.4 x 10(-3) ml.g-1.min-1 for xenograft and "normal" brain respectively. This highly selective depletion of glutathione in neoplastic tissue versus surrounding non-neoplastic host tissue may have therapeutic implications for the rational use of chemotherapeutic and radiotherapeutic intervention. 相似文献
996.
Richard F. Lee Kurt C. Pice Vassilis C. Stamoudis 《Archives of environmental contamination and toxicology》1988,17(5):651-656
A liquid Chromatograph equipped with a short (3 cm) reverse phase column and electrochemical detector was used to characterize aromatic amines in shale oil, synthetic oil, and coal gasification streams. Five major peaks were produced from each sample mixture. The composition of the peaks was determined by high performance liquid chromatography with a long (25 cm) reverse phase column and by gas chromatography/mass spectrometry. Amines in the various peaks included aminonaphthalenes, aminobiphenyls, aminofluorenes, and aminophenanthrenes plus aminoanthracenes. The concentration of aminofluorenes, and aminophenanthrenes plus aminoanthracenes correlated with relative mutagenicity of the base fraction from the oils or tars. The levels of 2- and 3-ringed aromatic amines from shale oil and oil from the Great Plains commercial coal gasification plan were 24 and 184 g/g tar, respectively, while the respective mutagenicities were 8 and 214 revertants/g base fraction. This technique has the advantages of high sensitivity and rapid analysis, and could be used to screen for the presence of mutagens in synthetic fuel samples. 相似文献
997.
目的:研究骨转换标志物Ⅰ型胶原氨基端前肽(procollagen type Ⅰ N-terminal propeptide,PINP)、Ⅰ型胶原羧基端前肽(β-cross-linked ctelopeptide of type I collagen,β-CTX)在帕金森病(Parkinson’s disease,PD)并发骨质疏松中的预测价值。方法:纳入PD患者105例,根据是否合并骨质疏松分为骨质疏松组和非骨质疏松组,对所有患者检测25(OH)D、甲状旁腺激素、骨钙素、β-CTX、PINP等骨代谢指标,分析各指标与骨质疏松发生之间的关系。结果:①骨质疏松组少动强直型比例、女性比例、PINP、骨钙素、β-CTX水平均高于非骨质疏松组,骨质疏松组25(OH)D水平低于非骨质疏松组,差异均具有统计学意义; ②相关分析结果显示PD患者骨质疏松发生与骨钙素(r=0.28,P=0.005)、β-CTX(r=0.36,P=0.001)、PINP(r=0.40,P<0.001)均呈正相关,与25(OH)D(r=-0.30,P=0.002)、PINP/β-CTX(r=-0.56,P<0.001)均呈负相关,差异具有统计学意义;③多因素二元Lo- gistic 回归分析显示,25(OH)D(OR=0.95,95%CI:0.84~0.98,P=0.041)、PINP/β-CTX(OR=0.90,95%CI:0.83~0.98,P=0.017)是 PD病合并骨质疏松的独立危险因素;④ROC曲线分析示25(OH)D联合PINP/β-CTX时ROC曲线下面积最大,AUC=0.82,灵敏性=0.80,特异性=0.84,P<0.001。结论:血清25(OH)D水平及PINP/β-CTX比值与PD患者骨质疏松发生密切相关,在PD患者骨质疏松的发生中具有重要的预测价值,二者联合检测时诊断价值更高。 相似文献
998.
心房颤动是临床常见的心律失常,已有研究证明其与严重不良心脑血管事件(心力衰竭、脑卒中和心肌梗死)有关,目前全球心房颤动的患病人数超过了3 300万,预计未来40年内其患病率将增加1倍以上。多年来,医学相关人员在探究心房颤动的病理生理机制及开创改进其治疗方法等方面付出了大量努力。目前心房颤动的治疗管理仍是临床医学上的一个难题,尽管心房颤动治疗的手术消融和导管消融技术已逐渐趋于成熟,但对于心房颤动最佳的治疗方式、消融能量的选择尚无统一定论。导管消融通常需要多次手术且成功率低,而手术消融术后不良事件发生率较高。近年来,鉴于心脏外科医生和电生理学家之间的密切合作,结合导管及微创手术消融诞生了一种治疗心房颤动的新型策略——混合消融模式。混合消融克服了导管消融和微创手术消融的缺点,减少了不良结局,在治疗持续性心房颤动,尤其是长期持续性心房颤动上取得了可观的成效。本文主要通过回顾心房颤动消融的研究进展,对比分析目前混合消融模式治疗心房颤动的现有研究成果,归纳总结这种新型心房颤动治疗策略的优势与挑战,以期为临床心房颤动的治疗提供更多选择。 相似文献
999.
目的探讨SNHG6对急性心肌梗死(AMI)小鼠左心室心肌的影响。 方法将30只雄性C57/BL6小鼠构建成AMI小鼠后随机均分为AMI组、AMI+SNHG6组、AMI+miR-101-3p组、AMI+SNHG6+miR-101-3p组、AMI+miR-101-3p+TGFBR1组,另设正常小鼠6只为假手术组。qRT-PCR检测AMI小鼠SNHG6、miR-101-3p表达水平。心脏彩超检测各组小鼠左室射血分数(LVEF);马松和天狼星红染色法以及免疫组化分析各组小鼠左心室心肌纤维化变化。将H9C2细胞株分为阴性对照组(转染空质粒)、SNHG6组(转染质粒SNHG6)、miR-101-3p组(转染质粒miR-101-3p)。Western blotting检测各组TGFBR1蛋白表达;采用双荧光素酶报告基因法预测并验证SNHG6/miR-101-3p/TGFBR1荧光素酶活性及调控机制。 结果AMI小鼠较假手术组SNHG6表达显著增加,miR-101-3p降低(P<0.05)。与AMI组比较,AMI+SNHG6组小鼠LVEF降低,心肌纤维化程度加重(P<0.05);AMI+miR-101-3p组LVEF升高,心肌纤维化程度减轻(P<0.05)。AMI+SNHG6+miR-101-3p组较AMI+SNHG6组LVEF升高、心肌纤维化程度减轻(P<0.05),而AMI+miR-101-3p+TGFBR1组较AMI+miR-101-3p组LVEF降低、心肌纤维化程度加重(P<0.05)。双荧光素酶报告基因法验证显示,miR-101-3p组SNHG6、TGFBR1野生型质粒的荧光素酶活性较阴性对照组明显降低(P<0.05)。 结论SNHG6抑制miR-101-3p上调TGFBR1加重AMI小鼠左心室心肌纤维化。 相似文献
1000.
胃黏膜上皮内瘤变是胃癌前病变,具有发展为胃癌的危险。阳主动,阴主静,文章基于阴阳理论,衷中参西,微观辨证与宏观辨证结合,以阴阳消长失调和基因调控紊乱的关系为出发点,认为胃黏膜上皮内瘤变发生时胃黏膜细胞凋亡周期紊乱和细胞异常增殖分化是阴阳消长失衡在细胞基因调控水平上的体现,进而探讨胃黏膜上皮内瘤变的病因病机以及辨证论治过程,为中医药治疗胃黏膜上皮内瘤变提供更多的理论依据,丰富治疗该病的临床手段。 相似文献