A Study on Using Improved Methenamine-silver Stain to Diagnosis of Pneumocystis carinii

ＡＳｔｕｄｙｏｎＵｓｉｎｇＩｍｐｒｏｖｅｄＭｅｔｈｅｎａｍｉｎｅ－ｓｉｌｖｅｒＳｔａｉｎｔｏＤｉａｇｎｏｓｉｓｏｆＰｎｅｕｍｏｃｙｓｔｉｓｃａｒｉｎｉｉＣｈｅｎＸｉｗｅｉ（陈锡慰）（ＤｅｐａｒｔｍｅｎｔｏｆＰａｒａｓｉｔｏｌｏｇｙ，ＮａｎｊｉｎｇＭｅ...     

甲氟哌酸药代动力学研究

本文报道国产甲氟哌酸片剂的人体药代动力学研究结果。血、尿药物浓度用微生物打孔法测定。健康志愿者口服甲氟哌酸400mg片剂后,体内药物转运过程符合一室开放模型。甲氟哌酸的血药浓度达峰时间、峰浓度为1.27小时和4.76μg/ml。T_(1/2)Ka和T_(1/2)Ke分别为0.22和10.40小时。研究结果表明,甲氟哌酸吸收快,达峰迅速,血清峰浓度有所提高,消除半衰期长,体内分布广泛,值得在临床推广使用。     

International round robin tests on the measurement of carbon in diesel exhaust particulates

Object: Diesel soot has been recognized as probably carcinogenic to humans. Elemental carbon (also called black carbon) in soot is considered at the moment as the most significant surrogate to be measured for assessing the exposure to this pollutant. Its analysis is done by combustion in an oven and determination of the CO₂ formed, after elimination of the organic fraction of the soot by heating and/or by solvent extraction. The analysis allows determination of both fractions of the soot: “elemental carbon” (EC) and organic carbon␣(OC). The sum of EC and OC is called TC (total carbon). Method: An informal European coordination group organized two round robin tests on filter samples collected from diluted diesel emissions. The first round (RRT1) was performed on 13 different samples analyzed by ten laboratories. The range of loading was 2.5 to 150 μg/cm² of EC. No evaluation of the precision within laboratories could be made since each laboratory gave only one result per sample. Therefore a second round (RRT2) was organized with two samples and a blank filter sent in several portions to 11 laboratories. It should be stressed that each laboratory used its own method and that no standardization was planned at this stage. Results: Results of RRT1 showed that the coefficient of variation between laboratories decreased with higher loading and was around 10% to 15% for EC above about 20 μg/cm². Dispersion of the results varied and it appeared that the way OC is removed from the soot is probably the most important factor of influence. The correlation between the laboratories was good as a whole but some systematic differences could be detected. Besides the different techniques to remove the organic carbon, the pretreatment of the filter by HCl (either as a vapor or as a solution) to remove the inorganic carbonates (potential interference sources), is probably also a significant factor of influence in the dispersion of the results between laboratories. It is not yet clear from these results whether the “environmental” laboratories give different results from the “occupational” laboratories, but it is clear that their objectives differ since for the “environmentalists”, EC is not a specific marker of diesel immissions, in contrast to the “occupationalists”. Conclusion: It can be concluded that, although significant differences exist between laboratories they can be attributed mainly to the narrow distribution of the results within a single laboratory, and that the overall agreement of the results for EC and TC is fairly good. These results obtained with pure diesel engine emissions, should be complemented by field samples, but they have already achieved relevant findings in the performance of the procedures used to assess exposure to diesel soot. Received: 30 December 1996 / Accepted: 21 February 1997     

紫外分光光度法测定甘氨酸茶碱钠中茶碱的含量

本文建立了用于甘氨酸茶碱钠中茶碱含量测定的紫外分光光度法。将样品溶于０．１ｍｏ１／Ｌ氢氧化钠溶液中，在２７４ｎｍ波长处测其吸收度，结果的相对标准偏差（ＲＳＤ）为０．２２％．与药典方法比较，Ｆ．ｔ检验均无显著性差异．本法简便，快速，结果可靠，准确．     

凝集素受体在膀胱癌中的分布

目的：探讨膀胱癌中凝集素受体分布与其分化程度和浸润深度的关系。方法：应用生物素标记的花生凝集素（ＰＮＡ）、麦胚凝集素（ＷＧＡ）及刀豆凝集素（ＣｏｎＡ）等３种凝集素对５２例人体膀胱癌、１０例正常人体膀胱粘膜，进行亲合组织化学法研究。结果：发现正常膀胱粘膜ＰＮＡ、ＷＧＡ受体阴性，ＰＮＡ受体阳性率随膀胱癌病理分级的上升而递增，差异具有显著性意义（Ｐ＜０．０５）。ＰＮＡ、ＷＧＡ受体阳性率在浸润性肿瘤中明显高于浅表性肿瘤（Ｐ＜０．０５）。结论：提示ＰＮＡ、ＷＧＡ受体阳性率与膀胱癌分化程度和浸润深度有关。     

2-chloroprocaine antagonism of epidural morphine analgesia

Background: 2-chloroprocaine (2-CP) used for lumbar epidural anesthesia (LEA) reportedly decreases the efficacy of epidural morphine (EM) administered for post-cesarean section (CS) analgesia. The amount of supplemental i.v. morphine self-administered by the patient via the patient-controlled analgesia device (PCA) is used to study the interaction between EM and 2-CP.
Methods: Forty-two patients scheduled for elective CS were randomly divided into 3 equal groups, and received 2-CP, 2-CP+epinephrine (Epi, 5 μg ml^-1) or 2% lidocaine (Lido) with Epi for LEA. All patients received 5 mg EM and i.v. PCA morphine for postoperative pain. Cumulative amount of i.v. morphine used in the first 24 hours as well as the amount of the drug used during each 2-h period were noted. Nonparametric analysis of variance and Chi-squared analysis were used for statistical comparisons.
Results: The mean cumulative 24-h i.v. PCA morphine requirement in the 2-CP, 2-CP+Epi and Lido+Epi groups respectively was 20.5±24, 33.1.5±27 and 4.07±6.3 (mean±SD). The Lido+Epi group used significantly less morphine ( P = 0.01) compared to either of the 2-CP groups with no significant difference between the 2-CP groups. The maximum i.v. PCA morphine use occurred in the first 4 hours following surgery in all three groups.
Conclusion: Analgesic efficacy of EM is decreased when 2-CP is used for LEA compared to when Lido+Epi is used.     

A Comparative Study of the Percutaneous versus Intraoral Technique for Mental Nerve Block

Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.     

An evaluation of numerical integration algorithms for the estimation of the area under the curve (AUC) in pharmacokinetic studies

Six numerical integration algorithms based on linear and log trapezoidal methods as well as four cubic-spline methods were proposed for estimation of area under the curve (AUC). These six different algorithms were implemented using IMSL/IDL^TM command language and evaluated using data simulated under five different dosing conditions and two different sampling conditions. Comparisons between AUC estimations using these six different algorithms and the theoretical results were made in terms of both overall AUC values and the superimposability of the concentration-time profiles. In well designed studies with ample data points, the algorithm based on IMSL/IDL^TM function CSSHAPE with concavity preservation gave the best performance. In contrast, when the frequency of blood collection was limited, the algorithm based on the log trapezoidal rule proved to be stable with reasonable accuracy, and is recommended as the practical method for numerical interpolation and integration in pharmacokinetic studies. Algorithms based on the combination of the log trapezoidal rule and cubic-spline methods using IMSL/IDL^TM function CSSHAPE can be developed to enhance overall performance.     

Clinical experience with minimal flow xenon anesthesia

Xenon is a more potent anesthetic than nitrous oxide, and gives more profound analgesia. This investigation was performed to assess the potential of xenon for becoming an anesthetic inspite of its high manufacturing cost. Seven ASA I—-II patients undergoing cholecystectomy (n = 4), hernia repair (n = 2), or mammoplasty (n=l) were studied. Denitrogenation by 15–20 min of oxygen breathing under propofol anesthesia was followed by fentanyl–supplemented xenon anesthesia administered via an automatic minimal flow system which held the oxygen concentration at 30%. Xenon anesthesia lasted 76–228 min and 8–14 1 of xenon (ATPD) was used, of which 5.6–8.1 1 was expended during the first 15 min. Anesthesia appeared to be satisfactory, and the patients woke up rapidly after xenon was discontinued. The automatic system made minimal flow xenon anesthesia easy to administer, but nitrogen accumulation is still a problem. Assuming a xenon price of 10 US $ per litre, the average cost for xenon was about 65 US $ for the first 15 min and then about 25 USS for each subsequent hour of anesthesia.     

Fluctuations in Tumor Blood Flow under Normotension and the Effect of Angiotensin II-induced Hypertension

To elucidate the significance of angiotensin II (AID-induced hypertension chemotherapy, changes of tissue blood flow both in normal subcutis and in tumors (AH109A, LY80) were measured with the hydrogen gas clearance method. A newly-developed anesthetic machine was used to keep the animals' condition constant. Tissue blood flow in normal subcutis and tumors always fluctuated with time under normotension. The nature and the rate of fluctuation in tumor Wood flow were almost identical in two different types of tumors. However, the fluctuation of blood flow in tumor and that in normal subcutis were almost always inversely related when blood flows in these different tissues were measured simultaneously, i.e., when tissue blood flow in normal subcutis decreased, tumor blood flow increased, and vice versa. The findings supported the idea that the connection mode between the tumor vascular bed and normal vascular bed is a parallel circuit. Vascular resistance in the normal vascular bed under All-induced hypertension seemed to be greater than that under normotension, because the All-increased tumor blood flow always exceeded the maximum tumor blood flow under normotension. Due to the fluctuations of tumor blood flow, no-flow or low-flow areas, resistant to delivery of anti-cancer drugs, moved sporadically within the tumor under the normotensive condition. However, good conditions for drug delivery to tumor tissue were induced by All-induced hypertension.