KD306型耐硫甲烷化催化剂有效扩散系数的测定

基于开发的计算机取样系统,采用ＳＰＳＲ法脉冲动态测试ＫＤ３０６型耐硫甲烷化催化剂的有效扩散系数。线性化和参数估值的结果吻合较好,证实：线性化简化是合理的,参数估值是可用于有效扩散系数。ＫＤ３０６型耐硫甲烷化催化剂的曲折因子为７．２。     

Pulmonary Failure After Norwood Procedure: Indication for Extracorporeal Membrane Oxygenation? A Case Report

Today some authors consider univentricular repair a contraindication for postoperative cardiac extracorporeal membrane oxygenation (ECMO). The question is whether or not ECMO is indicated as pulmonary support in case of an overwhelming pulmonary infection during the postoperative course after a Norwood procedure. During the prolonged weaning period after a Norwood procedure using a 4 mm aortopulmonary shunt, proven respiratory syncytial virus (RSV) bronchiolitis occurred at the time of expected weaning from artificial ventilation. Venovenous ECMO was able to improve oxygenation, but when pulmonary opacification failed to resolve, ECMO was terminated after 12 days.     

实验性屈光参差对双眼视功能的影响

目的 :探讨实验性屈光参差对健康成人双眼视功能的影响。方法 :对双眼视功能正常的大学生志愿者 32人采用在单眼前加不同度数正负球镜的方法 ,诱导单纯近视性 ( 1D , 2D , 3D)及单纯远视性 (-1D ,- 2D ,- 3D)屈光参差 ,测定诱导屈光参差后的视力、立体视敏度及Worth四点融像功能。结果 :随着屈光参差程度的增加 ,单纯“近视眼”的远视力逐渐下降 ,单纯“远视眼”的远视力几乎不下降。立体视敏度随着屈光参差度数的增加而下降 (t检验 ,P <0 .0 5 ) ,相同程度的单纯远视性屈光参差比单纯近视性屈光参差立体视敏度下降更明显 (t检验 ,P <0 .0 5 )。Worth四点定性试验证实了诱导屈光参差后双眼单视功能下降 (χ2 检验 ,P <0 .0 5 ) ,并有黄斑抑制的发生 ,Worth四点定量试验表明抑制区视角度数随着屈光参差程度的增加而增加 (t检验 ,P <0 .0 5 )。结论 :实验性屈光参差可引起成人双眼视功能异常 ,未矫治的屈光参差对儿童双眼视功能潜在性影响还需要进一步研究     

SPECT imaging of dopamine and serotonin transporters with [123I]β-CIT. Binding kinetics in the human brain

Summary Single photon emission computerized tomography (SPECT) studies in non-human primates have previously shown that the cocaine derivative [¹²³I]-2--carbomethoxy-3--(4-iodophenyl)-tropane ([¹²³I]-CIT) labels dopamine transporters in the striatum and serotonin transporters in the hypothalamusmidbrain area. Here, we report on the regional kinetic uptake of [¹²³I]-CIT in the brain of 4 normal volunteers and 2 patients with Parkinson's disease. In healthy subjects striatal activity increased slowly to reach peak values at about 20 hours post injection. In the hypothalamus-midbrain area peak activities were observed at about 4 hours with a slow decrease thereafter. Low activity was observed in cortical and cerebellar areas. The striatal to cerebellar ratio was about 4 after 5 hours and 9 after 20 hours. In 2 patients with idiopathic Parkinson's disease striatal activity was markedly decreased while the activity in hypothalamus-midbrain areas was only mildly diminished. Uptake into cortical and cerebellar areas appeared to be unchanged in Parkinson's disease. Consequently, in Parkinson's disease the striatal to cerebellar ratio was decreased to values around 2.5 after 20 hours. These preliminary methodological studies suggest that [¹²³I]-CIT is a useful SPECT ligand for studying dopamine and possibly also serotonin transporters in the living human brain.     

Myocardial perfusion damage after mediastinal irradiation for Hodgkin's disease: a thallium-201 single photon emission tomography study

Conflicting data have been reported on the incidence of myocardial abnormalities after mediastinal irradiation for Hodgkin's disease. We studied myocardial perfusion in 31 clinically asymptomatic patients (13 male, 18 female, mean age 35 years) 7 years (range 3–11 years) after mantle field radiotherapy. Thallium-201 tomoscintigraphic data were obtained after exercise, 4 h later and at rest (8–15 days later). Images were analysed visually and quantitatively (sectorial quantification of ²⁰¹T1 uptake on the bull's eye images of the short-axis slices) compared with those of 35 subjects with a low likelihood of coronary artery disease. Twenty-five tomographic data sets were available. Images were visually abnormal in 21 patients (84%) showing an heterogeneous ²⁰¹Tl uptake. In 68%, the sectorial ²⁰¹Tl uptake was lower than the mean ²⁰¹Tl uptake value minus 2 standard deviations measured in subjects with a low likelihood of coronary artery disease. Significant redistribution (quantitatively assessed 10%) was present in 10 patients (40%). In most of the patients, the location and the shape of the defect(s) could not be anatomically related to an epicardial coronary vessel disease. These results indicate that after mediastinal irradiation the ²⁰¹Tl myocardial uptake is frequently abnormal. The observed patterns suggest a disease of the small coronary vessels and/or the existence of a myocardial fibrosis rather than epicardial coronary artery disease.     

Reproducibility of quantitative hexakis-2-methoxyisobutylisonitrile single photon emission tomography in stable coronary artery disease

The quantification of myocardial perfusion abnormalities is necessary to allow comparison of repeated studies, especially in the evaluation of the success of medical, interventional or combined treatment in stable coronary artery disease or in evolving myocardial infarction. The purpose of this study was to assess inter-observer reproducibility of tomographic study processing using a semi-automatic quantitative programme. Technetium 99m hexakis-2-methoxyisobutylisonitrile (^99mTc-Sestamibi) was chosen for tomographic imaging of repeated rest-stress studies in patients with stable coronary artery disease. The quantification was performed using a modification of the Cedars polar coding and comparison with the normal data base. The perfusion defects were quantified separately for each standard perfusion area [left anterior descending (LAD), right coronary (RCA) and left circumflex (LCX) arteries] and total area of hypoperfused myocardium. The inter-observer variability for 40 tomographic studies was accomplished. The defects were the largest in the LAD perfusion area (average 19.7% of the normalized LAD supply area) with an inter-observer correlation of 0.84 for this region. The greatest variability was found for the LCX region (r=0.55) and is attributed to a small average perfusion defect (7.1%), only 18 studies having abnormal perfusion in this area. In total, an average 14.3% of the left ventricular myocardium was significantly hypoperfused, and the inter-observer correlation was 0.87. These results show good inter-observer reproducibility using semi-automatic quantitation of perfusion defects. Careful interpretation of smaller defects in the evaluation of treatment results is advised when repeated ^99mTc-Sestamibi single photon emission tomography studies are processed by more than one observer.The work was performed at Nuclear Medicine Department in Ulm. Offprint requests to: M. Milinski     

Analysis of the pharmacokinetics of lithium in man

Summary An analysis of the single and multiple dose pharmacokinetics of lithium in 7 healthy volunteers is presented. A solution of lithium chloride was administered in single dose experiments and the same solution and a sustained release preparation were employed in multiple dose experiments, which were carried out at steady state. A fixed dose of 24 mmol was used in the single dose experiments and in the subsequent multiple dose experiments in the same subjects the same dose was administered once daily for a week. Distinct two-compartment characteristics were found, with a mean disposition rate constant () of 0.035 h^–1±0.010 SD, corresponding to a mean biological half-life of about 19.8 h. The mean half-time of the distributory -phase was about 1.15 h. The absorption of lithium from an orally administered solution took place with a half-time of about 0.15 h in the single dose experiments. The apparent volume of distribution of the central compartment (V_c) was 0.307 1 kg^–1±0.046 SD, less than half that of V_de at equilibrium. V_d (V_darea) was 0.8291 kg^–1±0.184 SD and mean total body clearance was 27.6 ml kg^–1 h^–1±4.7 SD.     

预防非典型肺炎方剂对小鼠外周血液淋巴细胞 DNA损伤的影响

目的　研究预防非典型肺炎方剂对小鼠外周血液淋巴细胞 DNA的损伤作用。方法　应用单细胞凝胶电泳方法测定 6个预防非典型肺炎方剂体内给药对小鼠外周血液淋巴细胞 DNA损伤的作用。结果　ig给予预防非典型肺炎方剂 、 、 (1/ 3临床等效剂量、临床等效剂量、3倍临床等效剂量× 3 d)对小鼠外周血液淋巴细胞 DNA有明显的损伤作用 ,并呈剂量依赖关系。预防非典型肺炎方剂 、 、 (1/ 3临床等效剂量、临床等效剂量、3倍临床等效剂量× 3 d)对小鼠外周血液淋巴细胞 DNA没有明显的损伤作用。结论　预防非典型肺炎方剂 、 、 具有潜在的遗传毒性     

先兆子痫致早产在单-双胎妊娠中的母儿结局分析

目的　探讨重度妊高征先兆子痫致医源性早产在单胎妊娠和双胎妊娠中的母儿结局。方法　回顾性总结北京大学第一医院 1993年 1月～ 2 0 0 2年 12月间收治的孕周小于 37周的 12 2例单胎妊娠和 11例双胎妊娠的先兆子痫孕妇的妊娠结局。以单、双胎妊娠分为两组比较其发病情况、疾病进展、母儿并发症及结局。采用SAS软件进行计算机统计分析。结果　双胎妊娠与单胎妊娠发生妊高征及先兆子痫的差异无显著性 (P >0 0 5 )。双胎孕妇期待治疗时间明显短于单胎孕妇 (P <0 0 5 ) ,两组孕妇的母儿并发症及围产儿死亡率差异无显著性 (P >0 0 5 )。结论　双胎妊娠与单胎妊娠易发生妊高征及先兆子痫的可能性相同。如果双胎妊娠合并先兆子痫孕妇在积极控制病情 ,促胎肺成熟的同时及时终止妊娠 ,其母儿并发症及围产儿死亡率与单胎妊娠合并先兆子痫的母儿并发症及围产儿死亡率相同。     

克拉霉素的极谱催化波及其应用

目的建立灵敏快速测定克拉霉素的新方法。方法基于氧化剂存在时克拉霉素产生的极谱催化波,用线性单扫描极谱法快速测定克拉霉素。结果在0.24 mol·L^-1 KH₂PO₄-Na₂HPO₄ (pH 6.81)支持电解质中，克拉霉素于-0.79 V (vs SCE)电位处产生1个还原波。加入过二硫酸钾后，该还原波峰电流增加约20倍，峰电位基本不变，产生一极谱催化波。其二阶导数峰电流i_p″与克拉霉素的浓度在4.0×10^-7-5.0×10^-5mol·L^-1呈良好线性关系(r=0.999 1,n=10)，检出限为2.0×10^-7 mol·L^-1。结论该方法可用于药剂中克拉霉素含量的测定。