The CTFA Evaluation of Alternatives Program: an evaluation of in vitro alternatives to the Draize primary eye irritation test. (Phase III) surfactant-based formulations

The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data.     

火灾烟气特征的实验研究

烟气是火灾过程的重要物理现象 .烟气中悬浮的烟气颗粒目、尺寸分布、团聚效应和烟气的湍流效应是火灾探测的重要影响因素 .本文分析了火灾烟气的特征 ,为多参数特征的火灾探测提供了理论依据     

Bone marrow transplantation in adult thalassemic patients

One hundred seven adult patients with thalassemia aged from 17 through 35 years and transplanted from HLA-identical siblings between November 1988 and September 1996 were evaluated on December 31, 1997. The outcome experience of 20 consecutive patients transplanted between November 13, 1988 and January 10, 1991 and reported in September 1992 is updated after 5 additional years. The experience on 87 patients transplanted between May 1991 and September 1996 is described and evaluated as of the end of December 1997. Of 107 patients, 69 survive between 1.5 and 9 years after transplantation. Sixty-six of these patients do not have thalassemia and are identified as ex-thalassemic after bone marrow transplantation. The youngest survivor is 20 years old, 6 are older than 30 years, and the oldest is 37 years of age. Patients with chronic active hepatitis at the time of transplant were significantly more likely to die than patients without (P =.05; relative risk, 2.05). Marrow transplantation is a valid treatment option for older patients with thalassemia who have suitable donors and show deterioration with conventional therapy.