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51.
本文建立了以紫外230nm波长检测的反相高效液相色谱法(RP-HPLC)测定家兔血浆中甲苯喹派浓度。填料使用LiChrosorb RP-C18,流动相为甲醇—水—三乙胺—磷酸(63:37:1:0.8 v/v),血样(或尿样)经碱化后用乙醚提取,再以0.2 mol/L硫酸回提,进样。方法回收率为99.84±3.10(SD)%;天内、天间精密度平均CV为4.12%及3.95%(n=5);最低检测限3ng.经提取的标准线性浓度在25~2000 ng/ml范围内,Y=0.002865X-0.01346,r=0.9999,内源性物质及可能的合并用药不干扰色谱测定。文内用质谱法鉴定血样中甲苯喹哌色谱峰纯度,并由尿样分析对其主要代谢物予以初步验证。本法可应用于药代动力学参数测定。家兔按8mg/kg静注后,药—时曲线符合二室模型T1/2=4.8008±1.1522(SD)h。  相似文献   
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Recent studies on biological markers and risk factors for alcoholism have distinguished between nonalcoholic individuals with a family history of alcoholism and those without such a family history on measures of event-related brain potentials. The main finding of these "high-risk" studies is a smaller amplitude of the P300 component in males with a history of paternal alcoholism. This relationship between P300 amplitude and a family history of paternal alcoholism has been observed in adults and children. Consequently, several authors have suggested that a reduced P300 amplitude could serve as a vulnerability marker for alcoholism. We address several conceptual and methodological issues involved in the study of event-related potentials in children at high risk for alcoholism. Subsequently, the ongoing high-risk study of the Amsterdam Institute for Addiction Research is described briefly.  相似文献   
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The background and rationale of a recently started project of the Amsterdam Institute for Addiction Research are outlined. This project is aimed at the psychological mechanisms underlying an enhanced risk of (later) addiction in children of alcoholics and the relationship with childhood psychopathology. A dual pathway mechanism is proposed, in which the type of alcoholism of the parent plays a major role. The child of a multigenerational primary alcoholic parent may suffer from an inherited mild dysfunction of the prefrontal cortex, expressed in neuropsychological and personality characteristics similar to those of the alcoholic parent. These are impulsive, aggressive and reward-seeking behaviour, response perseveration and, in some children, related psychopathology such as conduct disorders. For a child of a secondary alcoholic parent, another mechanism is proposed. In these children, stress and social learning may lead to negative affectivity and repressive coping style, with emotional problems at a later age, and the risk of falling into the "circle of secondary alcoholism". In both pathways, alcohol-related expectancies are suggested to constitute a "final common pathway" between different risk factors and later alcohol abuse. Specific expectancies might be related to different pathways and to gender differences in later drinking patterns.  相似文献   
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小檗碱电化学检测器在中(成)药流动注射分析中的应用   总被引:1,自引:0,他引:1  
中药材及其制剂,因成分复杂,对其有效成分的测定,目前大多尚未建立适宜的方法。文献报道的测定方法有薄层—分光光度法、薄层扫描法、萃取—分光光度法、柱色谱—分光光度法及高效液相色谱法等,这些方法大多操作繁琐、分析周期较长、且分析的精密度和准确度亦不够理想。近年来,随着流动注射分析(FIA)及化学传感器的发展,中成药中有效成分的分析有了新的发展。本文报道了基于小檗碱流通型传感器的电化学检测器用于含小檗碱中(成)药样品的流动注射分析,方法简便快速,结果准确可靠,样品分析速度可达120次/h。  相似文献   
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全麻体外循环术后患者的保温治疗   总被引:1,自引:0,他引:1  
临床资料 我院2002—10/2004—10对587(男373.女214)例全麻体外循环术后患实施了保温治疗,年龄17天.75岁,其中婴幼儿64例,儿童209例,成人314例.体外循环术中采用血流降温至24—28℃,术毕复温至35℃.返回ICU病房30min后常规测量中心体温(肛温)和体表温度,如体温低于35℃、并有四肢末梢冰凉、躯体部花斑,或中心体温与体表温度差值超过3℃时,  相似文献   
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Schwerk  WB; Schwerk  WN; Rodeck  G 《Radiology》1987,164(2):369-374
Echomorphologic features of 57 testicular lesions (48 neoplasms, nine benign lesions) were analyzed prospectively by means of high-resolution real-time ultrasonography (US). There was a broad spectrum of texture patterns for testicular malignancies, 92% of which exhibited a predominantly decreased echogenicity compared with that of normal tissue. US findings alone could not be used to make a specific prediction of malignant disease or to classify a neoplasm histologically. However, different kinds of tumors exhibited characteristic echomorphologic features that corresponded to their gross morphologic appearance; a knowledge of these echomorphologic features is extremely useful for the US differentiation of tumors from nonneoplastic scrotal pathologic conditions. All neoplasms in this series displayed distinct abnormalities in parenchymal texture, and all were detected with US. The sensitivity and predictive value of a normal sonogram were as high as 100%. With regard to the detection of retroperitoneal lymph node metastases from testicular tumors, abdominal US had an overall accuracy rate of 96% and was of superior diagnostic value compared with bipedal lymphangiography.  相似文献   
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