柱前荧光标记高效液相色谱法对血浆中l-麻黄碱和d-伪麻黄碱的定量分析

l-麻黄碱和d-伪麻黄碱是生药麻黄中早为人知而至今仍被广泛用于临床的一对手性异构生物碱。由于二者为生药麻黄中的主要成分但药理活性不同,为便于临床监控及有效用药,高分辨高灵敏度的检测方法的开发迫在眉睫。本文以易于得到的dansylchloride为柱前荧光标识试剂,在确定了最佳衍生化及分离条件的基础上,建立了理想的色谱分析系统(线性检测范围1～800ng·ml^-1)。同时运用此方法,完成了对静注l-麻黄碱和d-伪麻黄碱后豚鼠血浆内该对手性异构体水平的考查,并且定量检测了服用中成药小青龙合剂后人血浆中的该对手性异构体。     

Pachygyriclike changes: topographic appearance at MR imaging and CT and correlation with neurologic status

Studies of 23 pediatric patients with pachygyriclike changes (PLCs) examined with computed tomography (CT) and magnetic resonance (MR) imaging were reviewed to determine topographic patterns and correlate them with various clinical syndromes and degrees of neurologic impairment. Three types of topographic distributions were identified: unilateral, diffuse, and bilateral nondiffuse (of which eight of 10 showed frontotemporal predominance). PLCs were an isolated finding in seven patients, were associated with various congenital syndromes in nine patients, and were associated with congenital infection in seven patients, six of whom showed marked white matter abnormalities. Although most patients had severe developmental delay, three with nondiffuse PLCs had less severe impairment, permitting less required care.     

The role of the meniscus in an instability model for osteoarthritis in the rabbit knee.

After division of the cruciate ligaments and one meniscus in the knee joint of the rabbit, degenerative changes were observed in both the articular cartilage and bone. This was more apparent on the tibial plateau in which the meniscus had been removed, progressive changes occurring from 3 to 16 weeks after trauma. A parallel in vitro experiment, involving measuring the lateral displacement of the tibia in the rabbit knee during medial-lateral leading, was performed before and after transverse division of the meniscus alone. The resulting displacements during medial-lateral shear loading approximately doubled after meniscectomy in the mechanical tests, the apparent clinical stability still being provided after meniscus division by the collateral ligaments, joint capsule, cruciates and bone geometry.     

The relationship between lead exposure, motor function and behaviour in Inuit preschool children

The main focus of this study was to determine the role of behaviour in the relationship between postnatal lead exposure and motor function. The sample consisted of 110 preschoolers, of age 5, from Nunavik. Lead concentration was measured at birth and at testing time. Average lead levels were of 4.9 microg/dL (0.24 micromol/L) and 5.3 microg/dL (0.26 micromol/L) for cord and child blood, respectively. Children's balance and fine motor capacities were tested. A modified version of the IBR was used to assess behaviour. Postnatal blood lead concentrations correlated positively with both impulsivity and activity. Neither pre- nor postnatal blood lead concentration correlated with attention level. The children's scores on impulsivity (I) and activity (A) were summed to create the independent variable IA, which was tested as a potential mediator between lead exposure and two dependent variables: the coefficient of covariation in alternating hand movements and transversal sway in tandem position. Mediation was significant only for the latter variable. IA and attention were then tested as potential moderators in the relation between postnatal lead exposure and motor function. No significant interaction between independent variables could be observed. These results do not support the hypothesis that, at low levels of postnatal exposure, lead acts indirectly on motor function via behaviour. However, IA does act as a mediator in the relationship between postnatal blood lead concentration and transversal sway in tandem position.