Simulation for population analysis of Michaelis-Menten elimination kinetics

A simulation study was conducted to compare the cost and performance of various models for population analysis of the steady state pharmacokinetic data arising from a one-compartment model with Michaelis-Menten elimination. The usual Michaelis-Menten model (MM) and its variants provide no estimate of the volume of distribution, and generally give poor estimates of the maximal elimination rate and the Michaelis-Menten constant. The exact solution to the Michaelis-Menten differential equation (TRUE) requires a precise analysis method designed for estimation of population pharmacokinetic parameters (the first-order conditional estimation method) and also considerable computational time to estimate population mean parameters accurately. The one-compartment model with dose-dependent clearance (DDCL), in conjunction with the first-order conditional estimation or Laplacian method, ran approximately 20-fold faster than TRUE and gave accurate population mean parameters for a drug having a long biological half-life relative to the dosing interval. These findings suggest that the well-known MM and its variants should be used carefully for the analysis of blood concentrations of a drug with Michaelis-Menten elimination kinetics, and that TRUE, in conjunction with a precise analysis method, should be considered for estimating population pharmacokinetic parameters. In addition, DDCL is a promising alternative to TRUE with respect to computation time, when the dosing interval is short relative to the biological half-life of a drug. This work was supported in part by the Epilepsy Research Foundation, the Nakatomi Foundation, and a Grant-in-Aid for Scientific Research from the Ministry of Education, Science, and Culture of Japan.     

天津市和平区354名老年人生活质量调查分析

目的 了解老年人的生存质量。方法 以健康状况调查问卷SF—36对天津市和平区新兴街354名印岁以上的老人进行调查。结果 天津市新兴街老年人的生活质量水平较高，但经济状况和慢性疾病是影响老年人生活质量的两个重要因素。结论 改善老年人的经济状况，预防和延缓老年性疾病的发生是提高老年人生活质量的重要措施。     

地衣芽胞杆菌对肠道致病菌的体内拮抗作用研究

目的:探讨地衣芽胞杆菌C01在模型小鼠体内对大肠杆菌、沙门氏菌抑制作用以及对乳杆菌等有益菌的促进作用。方法:用地衣芽胞杆菌C01灌胃肠道感染模型小鼠,采用体外活菌培养,分析粪便菌群数量的变化。结果:C01灌胃治疗组(EPEC C01)中乳杆菌的数量显著高于EPEC灌胃模型组(EPEC N)(P<0.01),肠杆菌数量下降极显著(P<0.01),而(EPEC N)组肠杆菌数显著高于正常对照组(NS)(P<0.05);肠炎沙门氏菌处理后C01灌胃治疗组(SL C01)和处理后肠炎沙门氏模型组(SL N)比较,乳杆菌、肠球菌和总厌氧菌的变化不明显,但肠杆菌数量下降极显著(P<0.01);形态病理学观察结果显示,C01芽胞杆菌灌胃治疗组肠粘膜病变明显减轻,肠粘膜及绒毛高度明显增加,绒毛轻度水肿,绒毛排列整齐、致密。结论:地衣芽胞杆菌C01在体内对肠炎沙门氏菌和致病性大肠杆菌有较强的抑制作用,能促进乳杆菌等生理性有益菌的增殖,可保护肠粘膜结构的完整性免受病原菌的侵袭。     

青年人群血清甲_3型流感抗体检测和流行株的抗原性分析

采集４５０例战士血清标本，分别用国家代表株甲３／济防／１５／９０（Ｈ３Ｎ２）和甲３／北京／３２／９２（Ｈ３Ｎ２）作血清血凝抑制抗体测定，青年对甲３型抗体阳性率为６０％～６７％，其ＧＭＴ为３４～４５。１９９４～１９９５年两年中在军营人群中分离到３株Ｈ３Ｎ２毒株流行株，分别应用国际、国家和地方代表株作抗原性分析，证明流行株与它们之间抗原性有明显差异。本文分离到的３株流行株均上送国家流感中心鉴定，证实为Ｈ３Ｎ２亚型毒株。     

医科蒙古族汉族大学生心理健康状况比较研究

目的：了解医科大学生的心理健康状况并进行民族、性别的比较。方法：采用ＳＣＬ－９０量表进行测查并进行统计分析。结果与结论：医科大学生ＳＣＬ－９０各因子均值都高于全国常模，有１９１％的学生存在较严重的心理卫生问题；汉族学生的心理卫生问题较蒙古族学生严重；女生的心理卫生问题较男生严重；人际关系、忧郁、强迫化是医科大学生主要的心理卫生问题。     

蒙古族,汉族新生儿蒙古斑研究

目的：调查蒙古族、汉族、蒙汉后裔新生儿蒙古斑的出现情况。方法：观察蒙古斑的数量、颜色、分布、面积，进行分析。结果与结论：蒙古斑出现率蒙古族为７８．７９％，汉族为７３．５４％，蒙汉后裔为８３．７０％。蒙古斑出现率无性别间差异。蒙古斑多分布于臂部和骶尾部。在有斑者中，人均斑面积为０．００２０ｍ＾２左右，斑面积与体表表面的比值多小于２％。     

Effect of electrical cutaneous stimulation on the level of succinate dehydrogenase activation and changes in glutamatergic synaptic transmission in response to sensory stimulation

It is shown that the rise of succinate dehydrogenase activity in the hippocampus depends on the number of sensory stimuli presented before decapitation, which correlates with changes in the efficiency of glutamatergic synaptic transmission in hippocampal sections from the same animal. Electrocutaneous stimulation potentiates the activation of succinate dehydrogenase induced by sensory stimulation probably due to enhanced glutamate release. Translated fromByulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 123, No. 4, pp. 404–407, April, 1997     

Seasonal variation in bacterial population and their correlation with physico‐chemical factors in the riverine system

Significant positive correlation between physico‐chemical factors and different bacterial populations were studied. Higher values of heterotrophic bacteria (HT), total coliform (TC), faecal coliform (FC) or faecal streptococci (FS) and the occurrence of E. coll, Streptococcus faecalis, Clostridium welchii ( C. perfringens), Aerobactor aerogens and A. cloacae at downstream point (Station II) indicated the degree of sewage and human waste pollution in the riverine system. The concentration of TC and FS at Station II was more than the prescribed permissible limits of ISI and WHO. Hence, the results show that river water has been deteriorating considerably due to high pollutional load and may pose a great risk to human health if consumed directly from the source.