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1.
通过正交试验方法,研究了硫酸钡吸光比浊法测定大蒜中大蒜素含量的最佳实验条件。在选定实验条件下,体系的吸光度与硫酸根离子浓度呈线性关系,相关系数r为0.9985,相对标准偏差(RSD)为0.86%。采用高效液相色谱法对样品中二烯丙基二硫醚进行定量检测,其检测结果与吸光比浊法的结果具有一定的互补对照性。在此基础上采用红外光谱法、气相色谱-质谱法对大蒜素中含硫活性成分进行定性分析,并将四种方法结果进行对比,对大蒜辣素过热分解的机理进行了探讨,为大蒜素中不同含硫化合物之间的转化提供了依据。 相似文献
2.
Y. W. Liu Z. Y. Wang Y. Liu C. X. Wang S. S. Qu F. J. Deng F. J. Li 《Journal of Thermal Analysis and Calorimetry》2001,66(3):903-767
Metabolic thermogenic curves of mitochondria isolated from fish liver tissue and the effect of Nd(III) on it were determined
by LKB-2277 Bioactivity Monitor, ampoule method, at 28.00°C. From these thermogenic curves, rate constant of the activity
recovery phase (k
1), rate constant of the stationary increase phase (k
2), rate constant of the decline phase(k
3), the maximum heat production rate (P
m) are obtained. These results show that Nd3+ has changed the metabolism of mitochondria completely.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
3.
冠心病(心肌纤维化)微量元素谱的多元分析 总被引:1,自引:2,他引:1
用ICP-AES分析了冠心病中心肌纤维化男、女患者血液中的19种元素含量,结果通过因子分析得到男女不同性能别的判别元素谱、应用非线性映射得以二维空间图、男性分辨率达96.6%,女性达87.3%。 相似文献
4.
Naoya Ichimaru 《Tetrahedron》2007,63(5):1127-1139
Δlac-Acetogenins are a new type of inhibitors of bovine heart mitochondrial complex I (NADH-ubiquinone oxidoreductase). We synthesized a series of Δlac-acetogenins in which the stereochemistry around the hydroxylated tetrahydrofuran (THF) ring moiety was systematically modified, and examined their inhibitory effect on complex I. The present results revealed that the inhibitory effects of the bis-THF ring analogs are much more potent than those of the mono-THF ring analogs and that the stereochemistry around the bis-THF ring moiety significantly influences the inhibitory effect. The profiles of the structure-activity relationship observed for Δlac-acetogenins were entirely different from those for natural-type acetogenins. 相似文献
5.
Wearing surgical face masks is among the measures taken to mitigate coronavirus disease (COVID-19) transmission and deaths. Lately, concern was expressed about the possibility that gases from respiration could build up in the mask over time, causing medical issues related to the respiratory system. In this research study, the carbon dioxide concentration and ethylene in the breathing zone were measured before and immediately after wearing surgical face masks using the photoacoustic spectroscopy method. From the determinations of this study, the C2H4 was established to be increased by 1.5% after one hour of wearing the surgical face mask, while CO2 was established to be at a higher concentration of 1.2% after one hour of wearing the surgical face mask, when the values were correlated with the baseline (control). 相似文献
6.
盐胁迫时铈保护小麦线粒体功能的研究 总被引:19,自引:3,他引:19
研究了小麦种子用Ce拌种后,在0.6%NaCl盐胁迫条件下萌发生长及对其根系线粒体功能的影响。Ce可降低因盐胁迫而升高的O^-2,.OH的水平,使脂质过氧化物含量和膜流动性趋于正常,提高因盐胁迫而降低的线粒体呼吸和氧化磷酸化活性。 相似文献
7.
The objective of the present study was to evaluate the effect of coconut water (Cocos nucifera L) and an isotonic drink on the changes of heart rate frequency in the rats induced hypertension. Wistar male rats were divided into five groups: a negative group, a mineral-watered group, a coconut-watered group, a group with isotonic drink, and a group with medicine. The rats were induced hypertension by administering NaCl solution high concentration for 14 days, and then they were treated with the test materials given to each group for another 14 days without stopping the induction. Their heart rate was measured using a tail cuff before the induction (d0), at the beginning of the treatment (d14), and at the end of the treatment (d28). When being induced hypertension, higher heart rate frequency was significantly showed by the groups with coconut water and isotonic drink (p<0.05) compared with the control group. When the rats of coconut water group were treated with coconut water, their heart rate became significantly lower (p<0.05) compared to the control groups. When the rats of isotonic drink group were treated with isotonic drink, their heart rate was lower, although not significant, than the control groups. The results showed that coconut water (C. nucifera L) lowered the heart rate frequency better than the isotonic drink. 相似文献
8.
目的通过研究并分析出冠心病患者的血脂组成成分,然后通过使用HCY测定的方法测定冠心病患者血清中的同型半胱氨酸含量的实际临床应用。方法 50例患有冠心病的患者和50名健康人员的血清成分中同型半胱氨酸含量,其中治疗组有25例无心肌梗塞的冠心病患者,其余25例研究对象均为有心肌梗塞患者,然后对治疗组患者的血脂组成成分进行测定并分析比较出异常成分。结果通过研究后发现治疗组的研究对象血清中的同型半胱氨酸含量远多于对照组的50例健康人员血清中的同型半胱氨酸含量,其中25例治疗组心肌梗塞患者的同型半胱氨酸含量多于25例治疗组的无心肌梗塞患者的同型半胱氨酸含量,具有统计学意义。冠心病患者的血脂组成成分Apo B100的值增加,冠心病患者的Apo A1的值和Apo A1与Apo B100的比值均减小,经统计学分析得出,具有统计学意义。结论血清同型半胱氨酸的含量改变,以及血脂中Apo B100的值和Apo A1的值与Apo B100的比值发生改变对治疗诊断与预防冠心病都有十分重要的价值。 相似文献
9.
10.
Fourier transform infrared (FTIR) spectroscopy has been proven to be an appropriate analytical method for the qualitative assessment of compost stability. This study focuses on quantitative determination of two time-consuming parameters: humic acid (HA) contents and respiration activity. Reactivity/stability and humification were quantified by respiration activities (oxygen uptake) and humic acid contents. These features are also reflected by a specific infrared spectroscopic pattern. Based on this relationship partial least squares regression (PLS-R) models for the prediction of respiration activities and humic acid contents were calculated. Characteristic wavenumber regions that are assigned to the biological/chemical parameter were selected for multivariate data analysis. The coefficient of determination (R2) obtained for the humic acid prediction model from infrared spectra was 87% with a root mean square error of cross-validation (RMSECV) of 2.6% organic dry matter (ODM). The prediction model for respiration activity resulted in a R2 of 94% and a RMSECV for oxygen uptake of 2.9 mg g−1 dry matter (DM). 相似文献
11.
Metabolic thermogenic curves of mitochondria isolated from liver tissue of Carassius auratus and the effect of different concentration of NaAsO2 on it were investigated by TAM air isothermal microcalorimeter, ampoule method, at 28.00 ℃. From the thermogenic curves, activity recovery rate constants k, the maximum heat production rate (Pmax) and the total heat produced (Q) were obtained. The values of k and Pmax decline gradually with the increase of the concentration of NaAsO2, and both of the values of Pmax and k are highly correlated to the concentration of NaAsO2. When concentration of NaAsO2 reached 16.0 μg/mL, the maximum heat production rate dropped to 70.8% of the control group, and the corresponding percentage of k was 71.4% of the control group. This experimental result indicates that the addition of NaAsO2 has restrained the metabolic activities of mitochondria in vitro. 相似文献
12.
Frazzoli C Dragone R Mantovani A Massimi C Campanella L 《Analytical and bioanalytical chemistry》2007,389(7-8):2185-2194
Toxicological implications of exposure to bioavailable platinum group metals, here Pd, Pt, and Rh, are still to be clarified.
This study obtained by a biosensor-based method preliminary information on potential effects on cellular metabolism as well
as on possible tolerance mechanisms. Aerobic respiration was taken as the toxicological end point to perform tandem tests,
namely functional toxicity test and tolerance test. Cells were suspended in the absence of essential constituents for growth.
The dose–response curves obtained by exposure (2 h) to the metals (nanogram per gram range) suggested the same mechanisms
of action, with Rh showing the greatest curve steepness and the lowest EC50 value. Conservative (95% lower confidence interval) EC10 values were 187, 85 and 51 ng g−1 for Pt, Pd, and Rh respectively. Tolerance patterns were tested during the same runs. The full tolerance obtained after 12 h
of exposure to each metal suggested mitochondrial inhibition of aerobic respiration as a target effect. The hazard rating
of the metals in the tolerance test changed in the Rh EC50 range, where Rh showed the lowest toxicity. The observed tolerance might suggest a protective mechanism such as metallothionein
induction at concentrations around the EC50 values. The performance of the bioassay was satisfactory, in terms of the limit of detection, repeatability, reproducibility,
roboustness, sensibility, and stability; the method’s critical uncertainty sources were identified for improvements.
Figure Respirometric curved 相似文献
13.
以微量元素为指标考察活心喷雾剂两种不同制备工艺 总被引:2,自引:0,他引:2
以微量元素Cu及Cu/Zn比值为指标,考察了活心喷雾剂两种不同制备工艺。结果表明:醇提工艺中Cu及Cu/Zn比值均明显高于水煎液,与以有效成分丹参酮ⅡA为指标考察工艺得出相同的结论。 相似文献
14.
本文旨在探讨高剂量瑞芬太尼对冠心病无痛胃镜检查患者循环系统及心肌损伤的影响。无痛胃镜检查的冠心病患者96例随机分为LR组(丙泊酚+瑞芬太尼0.2μg·kg^-1,n=48)和HR组(丙泊酚+瑞芬太尼0.5μg·kg^-1,n=48)。比较2组睫毛反射消失时间、胃镜检查时间、苏醒时间及丙泊酚用量,观察检查前(T 0)、检查开始即刻(T 1)、检查开始后5 min(T 2)、10 min(T 3)、检查结束即刻(T 4)SBP、HR、RPP及ST段、T波变化,并检测2组胃镜检查前和结束时cTnI、BNP等指标。结果显示,HR组睫毛反射消失时间、胃镜检查时间、丙泊酚用量低于LR组(P<0.05);T 3、T 4时HR组SBP、HR及RPP低于LR组(P<0.05);HR组T1、T2时ST段与T波改善情况优于LR组(P<0.05);HR组检查后cTnI、BNP水平低于LR组(P<0.05);HR组术中一般体动反应发生率低于LR组(P<0.05)。表明0.5μg·kg^-1瑞芬太尼复合丙泊酚用于冠心病无痛胃镜检查麻醉效果满意,对患者循环系统及cTnI、BNP的影响较小。 相似文献
15.
测定了116例冠心病患者血清中钙、镁、镉、铅、铍的含量并与正常对照组比较。结果显示,常量元素钙、镁与微量元素镉、铅含量降低,而铍的含量升高。它们之间的差异有显著性或高度显著性,P〈0.05或P〈0.01。 相似文献
16.
Cu(II)配合物很有可能成为下一代的抗肿瘤药物。本文以2-氨基-5-氯苯酚和2-喹啉甲醛合成的席夫碱作为配体,与Cu(II)络合形成配合物1。分别对配合物1和其与人血清白蛋白(HSA)的复合物HSA-1进行体外抗肿瘤测试,发现HSA能提高配合物1的抗肿瘤活性,并降低了对正常细胞的毒性。通过线粒体膜电位等实验,可以推断出配合物1是通过线粒体通路诱导癌细胞凋亡。 相似文献
17.
Investigation of Pathogenic Mineralization on Human Heart Valves. 1. Chemical and Phase Composition 总被引:1,自引:0,他引:1
L. G. Gilinskaya T. N. Grigorieva G. N. Okuneva Yu. A. Vlasov 《Journal of Structural Chemistry》2003,44(4):622-631
The chemical and phase composition of pathogenic minerals formed on human heart valves (cardiolytes) has been studied.It is shown that cardiolytes are organomineral aggregates, whose mineral component is represented by nonstoichiometric carbonate-containing hydroxyl apatites with a variable Ca/P atomic ratio. 相似文献
18.
M. B. Bogacki M. Wiśniewski J. Szymanowski 《Journal of Radioanalytical and Nuclear Chemistry》1998,228(1-2):57-61
Extraction of arsenic(V) from sulfuric acid solutions with various extractants in multistage counter-current extraction-stripping systems was compared. The extraction ability of the extractants studied showed the following order: ENIM 100>TBP=CYANEX 923>2-methylhexanol. The extraction depends significantly on the number of extraction stages and the phase ratios in extraction. The effects of the number of stripping stages and the phase ratio in stripping are less important. 相似文献
19.
冠心病患者全血微量元素锌、铜、铁的分析 总被引:2,自引:0,他引:2
李志锋 《广东微量元素科学》1996,(4)
用原子吸收法测定50例健康人、52例冠心病患者全血微量元素锌、铜、铁的含量,并对52例冠心病患者全血微量元素锌、铜、铁的含量及锌/铜比值,与其血脂总胆固醇(CH)、甘油三酯(TG)、高密度脂蛋白(HDL)、低密度脂蛋白(LDL)的浓度分别作线性相关分析。结果表明:(1)冠心病患者全血锌、铁、锌/铜比值均高于健康人(P<0.05),全血铜低于健康人(P<0.05)。(2)全血锌与HDL呈负相关(P<0.01)、锌/铜比值与总胆固醇呈正相关(P<0.05),铁与LDL呈正相关(P<0.01).提示锌/铜比值增高及体内铁储存增加均可能是冠心病易患因素. 相似文献
20.
本文运用代谢组学的研究方法,考察橙黄决明素对高脂血症大鼠血液内源性代谢物的影响,并寻找相关生物标志物。采用高脂饲料喂养的方法建立高脂血症大鼠模型,给予橙黄决明素灌胃治疗。利用气相色谱-质谱(GC-MS)联用技术分析高脂血症大鼠血浆中的代谢物,并使用主成分分析、偏最小二乘-判别分析和随机森林算法,研究大鼠样本在造模前后及橙黄决明素治疗后血浆内源性代谢物的变化情况,结果得到丙氨酸、甘氨酸、L-缬氨酸、异亮氨酸、富马酸、丝氨酸、1,5-脱水山梨醇、亚油酸、硬脂酸和胆固醇10种潜在的生物标志物。研究表明橙黄决明素主要通过影响机体氨基酸及脂肪酸的代谢,从而产生较理想的调脂作用。 相似文献