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71.
冯泳兰 《衡阳师范学院学报》1991,(3)
本文介绍在氯乙酸存在下,Ge—DDMBA—PF形成红色配合物测定锗的方法。配合物的组成为Ge:PF=1:2,最大吸收λ=530nm,摩尔吸光系数ε=1.45×10~51·mol~(-1)·cm~(-1);锗含量在0~5ug/25ml符合比尔定律。方法操作简单,显色快且稳定,用于铅锌矿渣中锗的测定,结果满意。 相似文献
72.
BackgroundDiabetes is a metabolic disorder caused by defects in insulin production and activity. During disease progression, changes in lipid peroxidation cause structural modifications via production of free radicals. Fangchinoline is a well-known alkaloid present in Stephaniae tetrandrine S. Moore, which has demonstrated antioxidant, anticancer, and anti-inflammatory activities.ResultsThe present study analyzed the anti-diabetic and antioxidant effects of fangchinoline in male rats with streptozotocin-induced diabetes. Rats were divided into the following groups: normal control, diabetic, diabetic + fangchinoline 100 mg/kg, diabetic + fangchinoline 200 mg/kg and diabetic + glibenclamide 600 µg/kg. The treatment was administered orally for 45 consecutive days. Lipid peroxidation was substantially increased by >50% in the serum, as well as the liver, kidney, and heart tissues of diabetic rats. However, fangchinoline supplementation significantly reduced lipid peroxidation to near normal levels. Reactive oxygen species levels were substantially increased by >500% in the serum, as well as the liver, kidney, and heart tissues of diabetic rats. Fangchinoline supplementation reduced reactive oxygen species to near normal levels. Fangchinoline supplementation significantly improved superoxide dismutase, glutathione peroxidase, catalase, and reduced glutathione levels in diabetic rats. Total hexoses, sialic acid, hexosamines, and fucose were increased in diabetic rats, whereas fangchinoline supplementation significantly reduced these total hexoses, sialic acid, hexosamines, and fucose to near normal levelsConclusionsSupplementation with fangchinoline led to significant attenuation of the levels of lipid peroxidation, ROS, and glycoprotein components such as total hexoses, hexosamines, sialic acid, and fucose, while improving antioxidant marker levels.How to cite: Xia J, Huang W, Zhou F. Effect of fangchinoline on oxidant status in male albino rats with streptozotocin-induced diabetes. Electron J Biotechnol 2021;53. https://doi.org/10.1016/j.ejbt.2021.07.005 相似文献
73.
采用培养皿发芽法,研究了水杨酸浸种对盐胁迫下西瓜种子萌发和幼苗生长的影响。结果表明,300mmol/L NaCl溶液浸种显著降低了西瓜种子的发芽率、发芽势、发芽指数和活力指数及胚根长和胚芽鲜重;1.0mmol/L以下浓度水杨酸浸种使盐胁迫下西瓜种子萌发和幼苗生长量随水杨酸浓度提高而显著增加;2.0 mmol/L水杨酸浸种对盐胁迫下西瓜种子萌发和幼苗生长无明显影响,3.0 mmol/L水杨酸浸种进一步降低了盐胁迫下西瓜种子萌发和幼苗生长量。结果说明,较低浓度水杨酸浸种可缓解盐胁迫对西瓜种子萌发和幼苗生长的抑制作用,减轻西瓜种子萌发期盐胁迫伤害的最适水杨酸浓度为1.0 mmol/L。 相似文献
74.
采用索氏提取方法提取柞蚕蛹油,用KOH/CH,OH酯交换法甲酯化处理,以气相色谱/质谱方法测定脂肪酸的组成.共鉴定出13种脂肪酸成分,其中以亚麻酸(LNA)、棕榈酸(P)、硬脂酸为主,柞蚕蛹油中不饱和脂肪酸含量占总脂肪酸总量的66.63%. 相似文献
75.
庄玉贵 《福建师大福清分校学报》1998,(2):60-65
本用PFS对含SiO22%的聚硅酸作了改性研究,当Fe/Si mol比小于2时,合成的PFSS溶胶体系稳定性有所增强,用Fe/Si mol比为1.5的PFSS絮凝处理受工业排水污染的含CODcr92mg/L,SS36mg/L,色度48倍,pH为6.5的混合污水,投量按Fe2O3计16mg/L时,絮凝30min后云污率大于90%,CODcr去除率达89%,比PFS节省Fe2O3投量约三分之一,显示出良好的电性和架桥的双重功效,是一种值得继续开发研究的新型复合无机絮凝剂。 相似文献
76.
以70%VO2max中等强度跑台耐力运动至疲劳为运动模型,测定了普通大学生服用不饱和脂肪酸对运动至疲劳时的闪烁融合阈值、憋气时间、定量运动时的心率和心电图。实验表明,服用不饱和脂肪酸对上述指标有一定的影响,受试者身体机能有一定改善,提示,不饱和脂肪酸可能与运动能力有关。 相似文献
77.
本文研究了海水基体和共存离子对镍和钒的影响,选用酒石酸、乙酸铵分别作为镍和钒的基体改进剂。未加基体改进剂前,海水镍回收率只有77%,钒的测量精度为11%;加人改进剂后均有改善。采用塞曼效应背景校正技术,热解涂层石墨管,建立了石墨炉原子吸收直接测定海水镍和钒的分析方法。镍和钒的特征质量值(mo)分别为8.4pg和17pg;实际检测限:镍为0.25μgL~(-1)和钒为0.41μgL~(-1)。回收率镍为86~110%,钒为88~106%范围。最大相对标准偏差为谋5.5%,钒4.2%。 相似文献
78.
M. P. Narayanan Vaidyanathan Kannan K. P. Vinayan D. M. Vasudevan 《Indian journal of clinical biochemistry : IJCB》2011,26(4):347-353
Organic acid disorders are inherited metabolic disorders in which organic acids accumulate in tissues and biological fluids
of affected individuals. Classical organic acidurias include methylmalonic aciduria, propionic aciduria, isovaleric aciduria
and maple syrup urine disease (MSUD). They are considered the most frequent metabolic disorders among severely ill children.
Patients frequently present with acute symptoms early in life. 420 cases clinically suspected to have organic aciduria, with
upper age limit of 12 years for a 2-year period (January 2007–December 2008) were enrolled into this study. Metabolic acidosis
and neurological symptoms were the most common signs. Screening tests and thin layer chromatography were done for detection
of organic acidurias. Identification and quantitation of organic acids in urine and quantification of amino acids in blood
were done by high performance liquid chromatography. Out of 420 patients, 45 patients (10.7%) were found to have organic acidurias.
15 cases of methylmalonic aciduria, 16 cases of propionic aciduria, 13 cases of MSUD, and one case of isovaleric aciduria
were diagnosed. Results demonstrate the importance of testing for organic acidurias. Since organic aciduria may cause irreversible
brain damage if not treated, we recommend selective screening amongst severely ill children despite implied extra costs. 相似文献
79.
80.
羽毛球比赛时间结构与供能特点的研究 总被引:9,自引:0,他引:9
对广东省羽毛球队参加国际、国内共42场比赛进行了时间结构和赛后血乳酸的测定。研究发现,羽毛球比赛的回合运动时间与间歇时间大部分在3~6秒和10~15秒之间。不同项目的比赛,时间结构不同,比赛时的供能特点不同,赛后血乳酸含量也不一样。赛后血乳酸含量随15秒以上回合运动时间的比例增大而增加,随0~3秒回合运动时间的比例增大而减少;比赛是在有氧代谢的基础上,以ATP—CP供能系统供能为主,无氧酵解供能为辅的方式供能。 相似文献