猪肝样品中铝含量的测定

目的介绍用石墨炉原子吸收分光光度法测定猪肝中铝含量的方法.方法样品在聚四氟消解器中消解.采用标准加入法在石墨炉原子吸收光度计上测定铝的含量.结果分析了8份猪肝样品,平均铝含量(4.10±0.17)μg/g,变异系数为4.3%.铝测定的回收率为96.3%±3.28%.用人发标样测定了方法的准确度为(13.1±1.8)μg/g,标准为(13.3±2.3)μg/g.结论这是一种准确、精密、可靠的分析方法.本方法也适用于其他生物组织样品中铝含量的测定.     

二氧二茂钛原料药的稳定性研究

利用紫外分光光度计对二氯二茂钛进行含量测定。回归方程为 :Y =0 9881X - 0 90 90× 10 -3(Y :吸光度 ;X :浓度 ,mg/L) ,相关系数r=0 9999,线性范围为 13 .6～ 81.6mg/L。模拟试验 3份 ,回收率为 98 4 5 %～ 10 1 3 3 % ,相对标准偏差为 0 14 %～ 0 3 3 %。本实验研究了原料药二氯二茂钛的稳定性 ,结果表明不同的湿度、温度等条件对二氯二茂钛的稳定性有一定影响     

紫外分光光度法测定甲磺酸酚妥拉明片的含量

目的 采用紫外分光光度法测定甲磺酸酚妥拉明的含量。方法 紫外分光光度法,检测波长２７８nm。结果 甲磺酸酚 妥拉明浓度在８．０～３３．０mg/Ｌ范围内,浓度与吸收度 呈良好的线性关系;r＝０．９９９ ９,n＝７,平均回收率为９９．７％。结论该方法简单、快速、精确、重现性好。     

渗透促进剂对栀子流浸膏透皮释放的影响

目的研究渗透促进剂对栀子流浸膏透皮释放的影响。方法采用紫外分光光度法,以栀子甙为指标进行栀子流浸膏的体外透皮释放量的测定。结果以累积透皮药量对时间作线性回归,得回归方程,并对各项下所得K值作方差分析,不同促进剂对栀子甙的透过率影响有显著性差异。结论2％月桂醇硫酸钠渗透促进作用最强,2％氮酮作用较弱,而2％的吐温80无促渗作用。     

铬酵母中铬的含量测定

目的 研究铬酵母中铬的含量测定方法。方法 采用氧化－光度法。结果 铬的平均回收率及相对标准偏差分别为１００．３％、２．７％（ｎ＝５）。结论 本方法可用于测定铬酵母中铬的含量,方法简便,易行。     

一阶导数紫外分光光度法测定注射用头孢噻肟钠的含量

目的探讨注射用头孢噻肟钠含量测定更加简便快速的方法;方法根据其化学结构的特点,采用一阶导数光谱法测定其含量;结果测定含量准确可靠且重现性好,平均回收率为99．87％(n=5),RSD为0．67％;结论可用于头孢噻肟钠原料药中问体和注射用无茵粉末等含量测定。     

铝-铬天青-溴化十六烷基啶胶束增溶分光光度法测定血清铝的方法研究

在溶液p H6-5 ～5-5 范围内,铝铬天青S(CAS)溴化十六烷基吡啶(CPB) 生成兰色三元胶束配合物,它的最大吸收在618n m 波长,摩尔吸光系数ε为9-642 ×104L.m ol-1 .c m -1 。在铝含量0 ～6-0 ×10 -6m ol.L- 1,遵循比耳定律,AlCASCPB三元配合物的组成摩尔比是1∶2∶3 。一定量的抗坏血酸和盐酸羟胺可以消除血清中与铝共存的其它阳离子Fe3 ,Cu2 等的干扰。该方法的检出限为6-60 ×10 - 7mol .L-1 ,平均回收率(96-11 ±2-87) % ,相对标准差小于3 % 。方法简便易行,有较高的准确度和灵敏度,用于血清铝的测定可获得满意结果     

Time-resolved confocal fluorescence microscopy of porphyrins for phototherapy

The application of a novel time-resolved confocal fluorescence microspectrometer to studies of the distribution and speciation of porphyrin photosensitizers in rat C6 cerebral glioma cells is described. The instrument combines a mode-locked argon ion laser excitation source with time-correlated single photon counting fluorescence detection and has sub-micron spatial and sub-nanosecond temporal resolution. The porphyrins studied were haematoporphyrin derivative (HpD), haematoporphyrin IX (HP), porphyrinc (Pc) and the tetrakiscarborane carboxylate ester of 2,4-(,-dihydroxyethyl) deuteroporphyrin IX (BOPP). From the heterogeneous emission observed in vitro, assignments and spatial location of various porphyrin species are proposed.     

Correlated, simultaneous, multiple-wavelength optical monitoring in vivo of localized cerebrocortical NADH and brain microvessel hemoglobin oxygen saturation

Current forms of brain monitoring, such as electroencephalography (EEG), have had limited clinical utility. The EEG records spontaneous cerebrocortical activity and thus is an indirect indicator of metabolic demand and, to a lesser extent, an indicator of mismatch of supply versus demand. Ischemia modulates EEG activity in ways that can usually be detected, but EEG patterns can be similarly modulated by many other factors, including temperature and pharmacologic manipulation. This in vivo study in physiologically monitored animals evaluated the use of correlated optical spectroscopy, performed with an instrument having a fiberoptic light-guide bundle in contact with the cerebral cortex, for the simultaneous monitoring of cerebrovascular oxygen availability and intracellular oxygen delivery. A highly specific monitor of cerebral intracellular oxygen supply, the cerebrocortical intramitochondrial NADH redox state, was monitored in vivo with a fluorescence technique. Absorption spectroscopy was used concurrently to monitor hemoglobin content (blood volume) and oxygen saturation in the microcirculation. Correlated changes in optical signals from cerebrocortical NADH and hemoglobin were studied in a swine model (n=7) of nitrogen hypoxia. Measurements were made at four wavelengths with a time-division, multiplexed fluorometer/reflectometer. Because the NADH fluorescence signal at 450 nm is affected by local changes in blood volume, a corrected fluorescence signal is usually calculated. In previous studies, where only two wave lengths have been measured, attempts at correction were based on reflectance at the excitation wavelength (366 nm). We compared estimators of changes in microcirculatory blood volume using reflection at two wavelengths: 366 nm and 585 nm, the wavelengths for maximum and isobestic absorption. The results of the studies were as follows: (1) during transient hypoxia, NADH and local hemoglobin saturation signals changed in concert with arterial pulse oximetry, with changes in NADH lagging behind changes in saturation by an average of 5.3 seconds; (2) after hypocapnic ventilation to a mean Paco ₂ of 20.2 ± 0.8 mm Hg, NADH increased by 11.5 ± 8.7% (as compared with maximal change during anoxia), local hemoglobin saturation decreased by 7.7 ± 6.4%, and local blood volume decreased by 12.5 ± 13%, while arterial SpO₂ was unchanged; (3) our two measures of local blood volume were closely correlated during carbon dioxide perturbations, but poorly correlated during hypoxic perturbation; and (4) NADH fluorescence provided a more rapid, sensitive indicator of oxygen deprivation than did the EEG. During transient hypoxia, EEG changes occurred 57.4 ± 10.4 seconds after the onset of decline in local hemoglobin saturation, after NADH had completed 50% of its maximal increase.This work was supported in part by research grants from the NIH (GM34767), the Academic Senate of the University of California, and the UCSF Anesthesia Research Foundation.     

Über Melanin und Melanosomen im ZNS im Vergleich zu extracerebralen Erscheinungsformen und synthetischem Melanin aus Dopamin und Serotonin

Summary Melanosomes and isolated melanosomal fragments (melanin particles) originating from gangliocytes (substantia nigra), astroglia (melanosis cerebelli), and melanocytes (melanotic meningeoma; metastases of melanoblastoma; melanosis thalami of the goat) were compared with synthetic melanins prepared from dopamine and serotonin, respectively. Samples were examined by electron microscopy, X-ray diffraction analysis according to Debye-Scherrer and by infrared spectrophotometry, and the results were evaluated with regard to characteristic features as they may relate to specific cell types or chemical structures.On electron microscopy all three types of melanosomes could be differentiated unequivocally as could the two synthetic melanins. Thus, there were similarities between synthetic melanin from dopamine and the gliogenic melanins of the cerebellum; the synthetic melanin from serotonin resembled melanin of melanocytes.X-ray diffraction analysis yielded 2-4 Debye diffraction rings with all human and synthetic samples, suggesting short range orders between 3.8 to 5 Å the sample obtained from a goat with thalamic melanosis showed a specific reflex pattern. While diffraction patterns of some melanins were partially identical, in particular that of melanin from dopamine and melanin of substantia nigra and dentate nucleus, respectively, they were different for the various melanocytic melanins. Further investigations are required to determine whether these differences are due to disparities in basic chemical structures or conformations or else, to particular compositional features of the various types of melanocytes as they arise from benign or malignant tumors or a specific species.Infrared spectrophotometry at higher wave numbers revealed the well known patterns of melanins, which are not, however, very suitable, for their further differentiation. At lower wave numbers (fingerprinting) melanin of substantia nigra and the glial melanin in melanosis cerebelli yielded additional absorption bands of identical configuration. In contrast to melanin from dopamine, melanin from serotonin exhibited a closely similar absorption pattern in this spectral range, suggesting that the neuroectodermal melanins may contain a component possibly arising from serotonin.

Herrn Prof. Dr. Wilhelm Doerr zum 25. 8. 1979