电位滴定法测定胰激肽释放酶活力测试条件探讨

本文用ＦＩＰ推荐的方法，以具有国际单位的参照品为标样，滴定液为０．０１ｍｏｌ／ＬＮａＯＨ标准溶液，考查了以ＢＡＥＥ为底物的电位滴定法测定胰激肽释放酶活力的实验条件，通过正交试验得出直观和方差分析的结果，依据酶活力单位高、ＳＤ和ＲＳＤ％较小的原则，求出酶活力测定的最适条件是：酶反应温度为２５℃；缓冲液为０．００１５ｍｏｌ／ＬＮａ２Ｂ４Ｏ７－０．２５ｍｏｌ／ＬＮａＣＬ－２×１０（－４）ｍｏｌ／ＬＥＤＴＡ，ｐＨ为８．００；反应液中酶浓度为０．４８ＩＵ／ｍｌ；底物浓度为５×１０（－３）ｍｏｌ／Ｌ；胰蛋白酶抑制剂浓度为１２５μｇ／ｍｌ。胰激肽释放酶活力测定的实验数据的相对标准偏差小于５％。     

胎盘组织液氨基酸的含量测定及层析鉴别

本文采用层析法进行鉴定,用氨基酸分析仪测氨基酸的含量,为胎盘组织液的质量标准提供可靠依据。本法准确率为99%。     

Ex Vivo Evaluation in Normal Dogs of Insulin Released by a Bioartificial Pancreas Containing Isolated Rat Islets of Langerhans

In bioartificial pancreatic systems, isolated islets of Langerhans are protected against immune rejection by an artificial membrane, permeable to glucose and insulin, but not to immunoglobulins and lymphocytes. Some of these devices, referred to as vascular systems, are set up to be connected to a vascular site in the recipient, with blood circulating in contact with one side of the membrane, and the islets on the other side. Such a bioartificial pancreas, containing isolated rat islets of Langerhans, was connected to an arteriovenous shunt of a normal anesthetized dog. The aim of this experiment was to investigate the kinetics of the insulin secretory response of the system to a glucose load. Glucose was infused upstream of the system, increasing the glucose concentration inside the bioartificial pancreas from 7 to 14 mmol/l, without altering the blood glucose concentration of the dog. Insulin concentration was determined simultaneously upstream and downstream of the bioartificial pancreas. Insulin production was calculated by multiplying the difference between these values by the blood flow rate. Blood flow rate (Q) was estimated from the change in the glucose concentration produced by the glucose infusion using a mass transfer analysis derived from Fick's principle. Insulin production increased from 20 +/- 8 to 59 +/- 15 microU/100 islets/min within 15 min following the beginning of the stimulation (n = 6, p less than 0.05). Five min after the end of the stimulation, insulin production decreased from 75 +/- 13 to 50 +/- 9 microU/100 islets/min (p less than 0.05) to reach the basal level (21 +/- 3 microU/100 islets/min) 30 min after the end of the glucose stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)     

Ocular Pharmacokinetics and Pharmacodynamics of Phenylephrine and Phenylephrine Oxazolidine in Rabbit Eyes

The aqueous humor concentration of phenylephrine and its corresponding mydriatic response were measured over time in New Zealand albino rabbit eyes following a 10-µl topical instillation of a phenylephrine HC1 viscous solution (10%) or a phenylephrine oxazolidine (prodrug) suspension in sesame oil (1 and 10%). The bioavailability of a 1% prodrug suspension in the rabbit eye (AUC of aqueous humor concentration vs time) was 30% lower than that of a 10% phenylephrine solution (P < 0.1) with the exception that the peak time occurred 34 min earlier with the prodrug. A 10% prodrug suspension increased the aqueous humor bioavailability approximately eightfold but improved the mydriatic activity (AUC of mydriasis vs time) only fourfold. The pharmacokinetic parameters, apparent absorption, and elimination rate constants, of phenylephrine and the prodrug were determined from aqueous humor concentration–time and mydriasis–time profiles. The study showed that the kinetic parameters of phenylephrine estimated from its mydriasis profile do not accurately reflect the kinetics of drug distribution in the iris. These parameters also varied with the instillation of phenylephrine solution or prodrug suspensions. A mydriatic tolerance of the pupil response was apparent after the topical instillation of phenylephrine solution. The mydriatic tolerance may be due to the decrease in receptor number in the iris dilator muscle.     

135例海洛因依赖者乙型肝炎病毒标志检测结果分析

１３５例海洛因依赖者乙型肝炎病毒标志检测结果分析张立学，郑纳新，赖倩（解放军３０７医院．北京．１０００３９）摘要＊＊本文对１３５例海洛因依赖者做乙型肝炎病毒（ＨＢＶ）标志物栓测，结果显示：ＨＢＶ感染阳性率为６５．９％，ＨＢｓＡｇ阳性携带率为７．４％．...     

Oral tolerance in EAE: reversal of tolerance by T helper cell cytokines

Oral administration of myelin basic protein (MBP) inhibits clinical and histopathological manifestations of experimental autoimmune encephalomyelitis (EAE), but only partially reduces serum anti-MBP antibody titers. We report here that orally administered MBP alters the isotypic distribution of anti-MBP antibody-forming cells (AFC) among various lymphoid tissues, with the most profound differences seen in mucosal tissues. We observed an isotype-selective reduction in anti-MBP IgA but not IgM AFC frequencies in Peyer's patches. The anti-MBP IgA AFC frequencies could be reconstituted by addition of interleukin 4 (IL-4) and interleukin 5 (IL-5). The cytokines did not appear to generate de novo responses since no increases in anti-MBP IgA AFC frequencies were observed in control cultures. These results indicate that decreased antibody production, as a result of oral antigen administration, can be reversed by exposure to the appropriate cytokines.     

海拔3417m世居及移居者无氧代谢阈与左心功能关系的探讨

在海拔３４１７ｍ对１８名健康世居藏族和１６名移居汉族用Ｊｅａｇｅｒ气体代谢自动分析系统和心阴抗图测定了无氧阈和最大摄氧量时的ＳＶ、ＣＯ、ＰＥＰ／ＬＶＥＴ和ＳａＯ２。结果显示：在海拔３４１７ｍ测得ＡＴ值明显低于海平面；世居藏族ＡＴ出现较晚，并且ＡＴ时的功率、ＶＯ２、ＭＶ、ＨＲ、ＣＯ、ＳＶ均高于移居汉族，而ＰＥＴ／ＬＶＥＴ比值小于移居组；两组的ＳＶ峰值出现时间不同，蕊居组在ＡＴ或ＡＴ以后出现的占７２％     

药物敏感试验指导肺癌合并恶性胸腔积液的顺铂联合其他药物胸腔内化疗

目的用药物敏感试验预测肺癌合并恶性胸腔积液癌细胞对顺铂联合其他药物的敏感度，观察其在指导此类患者的顺铂联合其他化疗药物胸腔内化疗的价值。方法将44例胸腔积液癌细胞阳性肺癌患者随机分为两组：药物敏感试验组（20例，有2例因体外药物敏感试验失败而被排除）和对照组（22例）。药物敏感试验组患者用三磷酸腺苷-肿瘤细胞药物敏感试验（ATP-TCA）法分别检测胸腔积液癌细胞对顺铂加香菇多糖、顺铂加甘露聚糖肽、顺铂加A群链球菌制剂、顺铂加干扰素、顺铂加金黄色葡萄球菌滤液制剂、顺铂加卡介苗多糖核酸、顺铂加红色诺卡菌细胞壁骨架、顺铂加白细胞介素-2的敏感度，并选择抑瘤率最高的联合化疗药物对患者进行胸腔内化疗，观察治疗后胸腔积液完全缓解率及胸腔积液癌细胞转阴率，并与对照组比较。结果药物敏感试验组患者对各联合化疗药物敏感的例数为：顺铂加香菇多糖14例、顺铂加甘露聚糖肽18例、顺铂加A群链球菌制剂17例、顺铂加干扰素10例、顺铂加金黄色葡萄球菌滤液制剂16例、顺铂加卡介苗多糖核酸15例、顺铂加红色诺卡菌细胞壁骨架17例、顺铂加白细胞介素-216例。药物敏感试验组完全缓解率为65．0％，对照组为27．3％（P〈0．05）。药物敏感试验组胸腔积液癌细胞转阴率为80．0％，对照组为45．5％（P〈0．05）。结论用药物敏感试验指导肺癌合并恶性胸腔积液的胸腔内个体化化疗可提高完全缓解率和胸腔积液癌细胞转阴率，该方法具有临床实用价值。     

动物喂养辐照食品的安全性评价

本试验是在多种食品的基础上,加大照射剂量(吸收剂量为0.1～8.0 kGy)和提高辐照食品在膳食中比例(千重80％以上)的条件下,进行了150d的大白鼠喂养试验。通过对饲料的营养成分分析及其利用,对动物的生长发育、血液学、致突变性及病理学等项指标的检测,结果证明是安全的。本试验结果为今后辐照食品商业化提供了安全的证据。