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151.
微分电位溶出法连测血清中铜铅镉锌 总被引:8,自引:1,他引:8
报道了微分电位溶出法先在0.0025mol.L^-1HCl-0.3mol.L^-1NH4Cl底液中连测血清中Cu、Pb、Cd,再加Ca^3+0.6μg、0.3mlNH4F(2mol.L^-1)于底液,稀释一倍后测Zn。Cu采用标准曲线法,Pb、Cd、Zn采用标准加入法。在选定条件下,四元素的线性关系良好。测试血汪有相对标准偏差≤4.6%,平均回收率为93.3%-101.3%,结果令人满意。 相似文献
152.
153.
以0、200×10-6、500×10-6、1000×10-6含铅饮用水染毒大鼠,在4、8、12周分批处死动物,取血、尿及组织分别测定铅、锌、钙等元素。结果表明,染毒200×10-6动物在4周时即出现全身症状;血铅浓度随染毒剂量增加而增高;尿铅、锌、钙的排出三者呈平行关系,排出高峰在4周。高尿锌导致脑、睾丸、骨、胰腺等组织锌含量降低,说明锌在铅中毒的发生机制中起重要作用,实验为应用锌制剂预防和治疗铅中毒提供依据。高尿钙所致机体影响有待进一步研究。 相似文献
154.
155.
Urea biosensors based on urease immobilized by crosslinking with BSA and glutharaldehyde coupled to ammonium ion-selective electrodes were included in arrays together with potassium, sodium and ammonium PVC membrane ion-selective electrodes. Multivariate calibration models based on PCR and PLS2 were built and tested for the simultaneous determination of urea and potassium. The results show that it is possible to obtain PCR and PLS2 calibration models for simultaneous determination of these two species, based on a very small set of calibration samples (nine samples). Coupling of biosensors with ion-selective electrodes in arrays of sensors raises a few problems related to the limited stability of response and unidirectional cross-talk of the biosensors, and this matter was also subjected to investigation in this work. Up to three identical urea biosensors were included in the arrays, and the data analysis procedure allowed the assessment of the relative performance of the sensors. The results show that at least two urea biosensors should be included in the array to improve urea determination. The prediction errors of the concentration of urea and potassium in the blood serum samples analyzed with this array and a PLS2 calibration model, based on nine calibration samples, were lower than 10 and 5%, respectively. 相似文献
156.
Three different electroanalytical techniques for the determination of zinc in blood are investigated. The direct determination in diluted blood via anodic stripping voltammetry at glassy carbon and the use of Nafion-coated glassy carbon mercury electrodes are shown to lack the necessary sensitivity whereas an acoustically assisted double extraction followed by sono-ASV using a glassy carbon electrode is found to be rapid, reliable and sensitive. 相似文献
157.
StudyofPreparationandCharacteristicsofPyridoxalated PolyhemoglobinLiangShuguang;TongMingrong;PanJilunandYuYaoting(Institutefo... 相似文献
158.
近红外光谱无创血液成分检测因其测量方法的优越性,已经成为生物医学领域的研究热点之一。但除血氧饱和度外,目前还没有进入临床应用成果的报道,其关键在于个体差异和测量条件对检测精度的影响。文章先介绍一种可以消除个体差异的新的检测方法——动态光谱法,再从其原理出发,推导出基于傅里叶变换的动态光谱频域提取法。同时,文章通过实验,研究了采样率,采样周期个数,非同步采样对(快速傅里叶变换(FFT)精度的影响。分析结果表明:选择合适的采样率,采样信号周期个数、并利用现有的加窗和插值算法能够大幅度提高动态光谱数据的精度。 相似文献
159.
Nakai T Matsuo K Kato C Takehara Y Isoda H Moriya T Okada T Sakahara H 《Magnetic resonance imaging》2000,18(10):907-1219
The blood oxygen level dependency (BOLD) contrast is a useful tool for functional neuroimaging based on the hemodynamic response to neuronal activation. We observed different hemodynamic responses in the BOLD signal between the primary sensorimotor area (SM1) and the supplementary motor area (SMA) in the sequential finger movement task. In the SMA, a stronger initial overshoot and a post-stimulus overshoot were observed. It was hypothesized from the time course analysis that the stronger initial overshoot reflected the activation of the SMA for motor control programming in the initial phase. Although the post-stimulus overshoot may be partially explained by cerebral blood flow (CBF) cerebral blood volume (CBV) uncoupling, its mechanism remained unknown. In the SM1, only the initial overshoot was observed and the level of BOLD signal was almost constant after the initial overshoot during the task period. These observations suggested that the BOLD signal is characterized by both CBF-CBV uncoupling and the neuronal activation characteristics in each region. 相似文献
160.
流动注射氢化物发生电加热石英管原子吸收光谱法测血清硒 总被引:4,自引:1,他引:3
采用自控电热消化器消化血清 ,消化液经流动注射氢化物发生 电加热石英管 原子吸收光谱法测定血清硒。该方法的检出限为 0 .4 5ng·ml- 1,同一血样 8次测定相对标准偏差为 3 59% ,用该法测定了冻干牛血清标准物质和牛血清标准物质 ,测定结果均落在标准物质的不确定度范围内。方法准确、简便、灵敏 ,已用于临床血清硒样本的测定 相似文献