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991.
992.
Initial clinical evaluation of gadolinium DTPA for contrast-enhanced magnetic resonance imaging 总被引:2,自引:0,他引:2
V M Runge W Schoerner H P Niendorf M Laniado D Koehler C Claussen R Felix A E James 《Magnetic resonance imaging》1985,3(1):27-35
Gadolinium DTPA was evaluated as an intravenous contrast agent for magnetic resonance imaging in 15 patients with primary or secondary intracranial neoplastic disease. T1 and T2 weighted images were obtained prior to contrast administration. T1 weighted spin echo 35/800 (TE/TR) images were utilized to detect enhancement. The increase in signal intensity observed, identifying areas of breakdown of the blood-brain barrier (BBB), was similar in magnitude to the contrast enhancement observed on CT. This permitted differentiation of neoplastic tissue from surrounding cerebral edema on MRI. Direct visualization of otherwise "isomagnetic" lesions was also demonstrated. The use of intravenous contrast media should significantly extend the diagnostic potential and specificity of magnetic resonance imaging. 相似文献
993.
中药复方小续命汤抗阿尔茨海默病有效成分组中6种有效成分的同时测定 总被引:1,自引:0,他引:1
建立了用高效液相色谱分析中药复方小续命汤抗阿尔茨海默病有效成分组中各成分的方法,并将其应用于此有效成分组的质量控制。采用ODS色谱柱,以水-甲酸-乙二胺(流动相A,体积比为100∶0.1∶0.1)和甲醇-甲酸(流动相B,体积比为100∶0.05)为流动相,采用梯度洗脱,流速1 mL/min,检测波长240 nm。在上述色谱条件下,可分离测定有效成分组中的6种成分。6种成分均具有良好的线性;其回收率分别为:芍药苷99.1%,升麻苷99.6%,黄芩苷98.4%,5-O-甲基维斯阿米醇苷99.9%,防己诺林碱99.6%,粉防己碱102.0%;相对标准偏差(RSD)分别为1.3%,1.4%,0.4%,0.8%,0.2%,1.4%。所建立的方法简便、快捷,可用于小续命汤有效成分组的质量控制。 相似文献
994.
A. Zlatkis C. F. Poole R. Brazell K. Y. Lee S. Singhawangcha 《Journal of separation science》1979,2(7):423-428
Nickel capillary columns coated with moderately polarstationary phases such as Witconol can be used for the separation of the organic volatile fraction from biological fluids. A “transevaporator” sampling technique for the collection of the organic volatiles on glass beads from as little as 5 to 500 μl of biological fluids (e.g. urine, serum, amniotic fluid, breast milk, saliva, etc.) is described. The organic volatiles are thermally desorbed from the glass beads into a short precolumn cooled in liquid nitrogen, which overcomes the problems associated with sample introduction onto narrow-bore capillary columns. The application of the full analytical technique to problems associated with the early detection of disease is illustrated. 相似文献
995.
Pascal Bindschdler Christian Noti Eva Castagnetti PeterH. Seeberger 《Helvetica chimica acta》2006,89(11):2591-2610
To test the hypothesis that tetrasaccharide 3 is involved in scrapie pathogenesis, tetrasaccharide derivative 32 functionalized with an amine linker at the reducing end was synthesized. A (2 + 2) glycosylation approach was chosen to furnish the target compound in fully protected form. To investigate its biological role, tetrasaccharide 32 was further functionalized to the corresponding thiol 33 using Traut's reagent. During the course of the synthesis, the N,N‐diacetyl protecting group proved surprisingly labile to radical and acidic conditions. 相似文献
996.
Regional distributions of manganese,iron, copper,and zinc in the brains of 6-hydroxydopamine-induced parkinsonian rats 总被引:1,自引:0,他引:1
Tarohda T Ishida Y Kawai K Yamamoto M Amano R 《Analytical and bioanalytical chemistry》2005,383(2):224-234
Time courses of changes in manganese, iron, copper, and zinc concentrations were examined in regions of the brain of a 6-hydroxydopamine
(6-OHDA)-induced rat model of Parkinson’s disease using inductively coupled plasma mass spectrometry (ICP-MS). The concentrations
were simultaneously determined in brain section at the level of the substantia nigra 1, 3, 7, 10, 14, and 21 days after the
6-OHDA treatment and compared with those of control rats. The distributions of these elements were obtained for 18 regions
of the sagittal section (1-mm thick). The ICP-MS results indicated that Mn, Fe, Cu, and Zn levels of the 6-OHDA-induced parkinsonian
brain were observed to increase in all regions that lay along the dopaminergic pathway. In the substantia nigra, the increase
in Mn level occurred rapidly from 3 to 7 days and preceded those in the other elements, reaching a plateau in the 6-OHDA brain.
Iron and Zn levels increased gradually until 7 days and then increased rapidly from 7 to 10 days. The increase in the copper
level was slightly delayed. In other regions, such as the globus pallidus, putamen, and amygdala, the levels of Mn, Fe, Cu,
and Zn increased with time after 6-OHDA treatment, although the time courses of their changes were region-specific. These
findings contribute to our understanding of the roles of Mn and Fe in the induction of neurological symptoms and progressive
loss of dopaminergic neurons in the development of Parkinson’s disease. Manganese may hold the key to disturbing cellular
Fe homeostasis and accelerating Fe levels, which play the most important role in the development of Parkinson’s disease. 相似文献
997.
肝豆状核变性病与人体内铜的关系 总被引:1,自引:2,他引:1
为探讨肝豆状核变性发病机理与人体内铜的关系,结合本实验室分析条件,用原子吸收分光光度法对509名患者的24小时尿铜、血清铜含量进行了检测。结果表明,109名患者的24小时尿铜含量远高于正常人水平,血清铜含量低于正常人水平,经诊断证实这些患者患有肝豆状核变性病。本文进一步对这些患者按不同年龄、不同性别进行了分析,为肝豆状核变性病的成因、发展、诊断及治疗提供参考依据。 相似文献
998.
通过原子吸收光谱技术探讨Gretves氏病人骨髓Zn、Cu、Mn、Se、Cr及Cu/Zu、Cu/Mn、Cu/Se、Cr/Zn、Cr/Mn、Cr/Se的变化,结果表明:患病组骨髓Cu、Cr、Cu/Zn、Cu/Mn,Cu/Se、Cr/Zn、Cr/Se较正常组明显升高,而Zn、Mn,Se明显降低,Cr/Mn两组比较无差异。计算机多因素逐步回归分析结果显示五种元素中Cu与T3关系最密切,六组元素比值中Cu/Se、Cr/Mu与T3关系量密切,Se元素与患者病程长短关系密切。 相似文献
999.
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
1000.
Metal ion-induced aggregation of Aβ into insoluble plaques is a central factor in Alzheimer’s disease. Zn2+ is the only physiologically available transition metal ion responsible for aggregating A β at pH 7.4. To make it clear that the neurotoxicity of Zn2+-induced aggregation of Aβ on neurons is the key to understand Aβ mechanism of action further. In this paper, we choose Aβ (10–21) as the model fragment to research hippocampal CA1 pyramidal neurons. For the first time, we adopt the combination
of spectral analysis with patch-clamp technique for the preliminary study of the mutual relations of Zn2+, Aβ and ion channel from the cell level. The following expounds upon the effects and mode of action of two forms (unaggregated
and aggregated) of Aβ (10–21) on hippocampus outward potassium channel three processes (activation, inactivation and reactivation). It also shows
the molecular mechanics of AD from the channel level. These results are significant for the further study of Aβ nosogenesis and the development of new types of target drugs for the treatment of AD.
Supported by the National Natural Science Foundation of China (Grant Nos. 30470408 and 20637010) 相似文献