Randomized clinical trial of ascorbic acid in the treatment of pressure ulcers

The objective of this study was to assess the effects of ascorbic acid supplementation, 500 mg twice daily in the treatment of pressure ulcers as an adjunct to standardized treatment.

The design consisted of a multicenter blinded randomized trial. The control group received 10 mg of ascorbic acid twice daily.

Patients from 11 nursing homes and 1 hospital participated.

Main outcome measures included wound survival, healing rates of wound surfaces, and clinimetric changes over 12 weeks.

Eighty-eight patients were randomized. Intention-to-treat analysis showed that the wound closure probability per unit time (i.e., the closure rate) was not higher in the intervention group than in the control group (Cox hazard ratio of 0.78 [90% precision interval, 0.44–1.39]). Mean absolute healing rates were 0.21 and 0.27 cm²/week in the intervention and control group, respectively (PI of the adjusted difference: −0.17 to 0.13). Relative healing rates and healing velocities did not show favorable results of ascorbic acid supplementation, either. A panel scored slides of the ulcers with a report mark between 1 (bad) and 10 (excellent). The improvement was 0.45 and 0.72 points per week in the intervention and control group, respectively (PI of the adjusted difference: −0.50 to 0.20). With another clinimetric index we could not show any differences, either.

These data do not support the idea that ascorbic acid supplementation (500 vs. 10 mg twice daily) speeds up the healing of pressure ulcers.     

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。     

离子选择电极电位法研究S2O8^2—与I^—反应动力学

用离子选择电极电位法对S_2O_8~(2-)-Ⅰ~-体系反应动力学问题进行了探讨,研究了离子强度对反应速度的影响。结果表明:离子选择电极电位法可用于此体系的动力学研究,并且得到满意的结果;提出了该电极适用的浓度条件;得出生成CuI~+步骤为催化反应决定步骤的新结论;随着离子强度的增加dE/dt值增大,即反应速度加快。     

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.     

PHA对单产和联产白细胞介素-2活性的影响

本文研究了用人外周血白细胞在细胞浓度为5×10~5个/ml、培养时间为24h,PHA加量对单独生产白细胞介素_2(单产)及联合生产a_干扰素、白细胞介素-2(联产)的影响.单产中,以25μg/mlPHA刺激量为宜;联产中以100μg/ml刺激量最好.联产比单产所得白细胞介素-2产量高10倍以上,且纯度高.     

中医药学研究方法的解构与特性分析

将中医药学研究方法从观念理论、核心方法和技术手段3个方面进行解构，并对其内在特性进行详细分析。明确提出中医药学研究方法的范式特性、观念理论的思辨性、核心方法的主观性以及整体刚性和局部柔性的特性，揭示了中医药研究方法的优势与不足，为中医药研究方法论的创新提供理论依据。