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We describe a simple direct extraction method for the gas-liquid chromatography determination of serum valproic acid. The working range for the assay is 2-180 mg/L and our within-run precision was 5.8 and 4.3% at the 40 and 90 mg/L concentrations respectively. Hemolyzed and lipemic sera as well as samples from patients with hyperbilirubinemia and from patients with decreased renal function were put through the assay and no interfering peaks were noted. Interference occurred when teflon-lined screw caps were used during the extraction step. The method was proven to be accurate by linear regression analysis of samples containing weighed-in amounts of valproic acid. The above assay was compared to an enzyme immunoassay technique (EMIT). The working range for the latter is 10-150 mg/L and the with-run precision was 10.8 and 5.9% and 90 mg/L concentration respectively. Samples were run by both the gas-liquid chromatograph and enzyme immunoassay methods and gave very similar results over the range 16-139 mg/L. 相似文献
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Karyotypic evolution in Ph-positive chronic myeloid leukemia in relation to management and disease progression 总被引:1,自引:0,他引:1
Birgitta Swolin Aleksander Weinfeld Jan Westin Johan Waldenström Bengt Magnusson 《Cancer Genetics and Cytogenetics》1985,18(1):65-79
In a prospective study of 32 patients with chronic myeloid leukemia the frequency of chromosome abnormalities in addition to the Philadelphia chromosome (Ph) increased when the disease progressed. Before metamorphosis, 10 patients (31%) had developed additional abnormalities. Such abnormalities were present in three of them at the time of diagnosis; in the other seven, they were detected late in the chronic phase. New clonal abnormalities heralded or accompanied a more malignant phase of the disorder, usually a blastic leukemia. During metamorphosis, 78% of the patients had additional abnormalities, which in 68% of these cases comprised at least one of +8, +22q- or i(17q). Clones with additional abnormalities disappeared in eight cases, either spontaneously or in association with cytostatic therapy during the chronic or blastic phase. Involvement of chromosome #8, usually in the form of a trisomy, was found in 7 of 12 patients treated with busulfan, but was not found in any of the 10 hydroxyurea-treated patients, of whom 8 were splenectomized early during the chronic phase. Cells from the spleen, obtained by fine needle aspiration or splenectomy were cytogenetically examined in 18 cases during the chronic phase, but abnormalities in addition to the Ph were noted in only one patient, who was examined in the late chronic phase. The same abnormalities were present in bone marrow cells of this patient. 相似文献
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Birgitta Swolin Aleksander Weinfeld Johan Waldenström Jan Westin 《Cancer Genetics and Cytogenetics》1983,9(3):197-209
Of 33 consecutive patients with chronic myelocytic leukemia, examined during metamorphosis, 82% showed chromosome abnormalities in addition to the Ph1. Aberrations most frequently encountered were +8 (39%), +22q - (30%), and i(17q) (18%). Translocations other than the Ph1 were observed in four cases and - Y clones in four cases. Discrepancies in the cytogenetic pattern between bone marrow and extramedullary tissues or blood were noted in a total of 15 patients. In six cases, transformation occurred in extramedullary organs at a time when it was not present in the marrow. In three cases the bone marrow transformation was preceded by a lymph node blastic infiltrate; in one case, by a skin infiltrate; and in one case, by a subdural blastoma. Clonal abnormalities additional to the Ph1 were identified in the tumor tissue from all these cases. Patients with primary extramedullary transformation tended to have a lower median age at onset of metamorphosis, shorter survival, and higher incidence of chromosome abnormalities than the cases without extramedullary involvement. Patients with only Ph1-positive cells and no other anomalies had a slightly longer duration of metamorphosis and longer total survival. Basophilia and thrombocytopenia were more marked in cases with i(17q) than in the rest of the series. 相似文献
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为了解盆腔手术前后血清电解质变化及其规律,于盆腔手术前24-48h及术后48-72h分别抽取静脉血,用离子选择电极法测定血清钾,钠,氯的水平,用全自动生化分析仪检测血浆钙离子浓度。 相似文献
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海洋生物柳珊瑚的化学成分及生物活性研究进展 总被引:7,自引:2,他引:7
柳珊瑚中含有许多结构新颖、生物活性多种多样的次生代谢产物,从而引起了人们对其化学成分及药理活性研究的极大兴趣。本文综述了1998年至2001年问有关柳珊瑚中化学成分及生物活性研究的最新进展,并在此基础上对这类海洋生物潜在的药用前景进行了展望。 相似文献
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混合稀土常乐对肾脏超微结构的影响 总被引:1,自引:0,他引:1
目的:研究长期服用混合稀土常乐对肾脏超微结构的影响。方法:健康W istar大鼠120只,随机分成对照组和2m g/kg体重、5m g/kg体重和20m g/kg体重三个剂量的实验组,每天给药1次,每周6d给药,第7d休息,连续给药90d,第91d处死动物,取肾组织制作超薄切片,电子显微镜观察并摄影。结果:2m g/kg体重剂量组滤过膜的厚度均匀,但足细胞次级突起发生融合;5m g/kg体重剂量组滤过膜厚度不均匀,足细胞次级突起融合增多;20m g/kg体重剂量组滤过膜不规则且厚度不均匀,足细胞次级突起融合较多。结论:混合稀土常乐对肾脏滤过膜的结构有影响,5 m g/kg体重和20 m g/kg体重的剂量对滤过膜结构较为明显。 相似文献