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51.
SD Gettings RA Lordo KL Hintze DM Bagley PL Casterton M Chudkowski RD Curren JL Demetrulias LC Dipasquale LK Earl PI Feder CL Galli SM Glaza VC Gordon J Janus PJ Kurtz KD Marenus J Moral WJ Pape KJ Renskers LA Rheins MT Roddy MG Rozen JP Tedeschi J Zyracki 《Canadian Metallurgical Quarterly》1996,34(1):79-117
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. 相似文献
52.
KJ Jones 《Canadian Metallurgical Quarterly》1996,23(3):463-476
As arthroscopy of the wrist moves into the second decade, the trend for more indications for both diagnostic and therapeutic procedures will continue. It is only a matter of time before arthroscopic fusions, soft-tissue repairs, and "ectomy" procedures of all kinds become more commonplace. Whereas the advantages of the early therapeutic techniques in preserving soft-tissue structures and shortening recovery are now obvious, we will have to wait and see if the same holds true for more complicated bony and soft-tissue procedures in the next decade. 相似文献
53.
54.
Extensive restriction site polymorphism at the human phenylalanine hydroxylase locus and application in prenatal diagnosis of phenylketonuria 总被引:4,自引:0,他引:4
AS Lidsky FD Ledley AG DiLella SC Kwok SP Daiger KJ Robson SL Woo 《Canadian Metallurgical Quarterly》1985,37(4):619-634
A total of 10 restriction site polymorphisms have been identified at the human phenylalanine hydroxylase locus using a full-length human phenylalanine hydroxylase cDNA clone as a hybridization probe to analyze human genomic DNA. These polymorphic patterns segregate in a Mendelian fashion and concordantly with the disease state in various PKU kindreds. The frequencies of the restriction site polymorphisms at the human phenylalanine hydroxylase locus among Caucasians are such that the observed heterozygosity in the population is 87.5%. Thus, most families with a history of classical phenylketonuria can take advantage of the genetic analysis for prenatal diagnosis and carrier detection of the hereditary disorder. 相似文献
55.
It is necessary to describe properly anisotropic material behavior for realistic numerical analyses of sheet metal forming processes. The implementation of many yield criteria in finite element analysis is very complicated. Various material tests are also required to determine yield function coefficients. Stress ratios and anisotropy coefficients are not constant during forming processes due to deformation induced anisotropy. This paper introduces a yield function using strain dependent plastic strain ratios and stress ratios. The main advantage is to fully utilize the data of uniaxial tensile tests. The described material behavior shows a significantly improved agreement with experimental data. 相似文献
56.
57.
Veselov S. N. Volk V. I. Kashcheev V. A. Posenitskiy E. A. 《Theoretical Foundations of Chemical Engineering》2018,52(4):735-742
Theoretical Foundations of Chemical Engineering - The operation of a linear crystallizer, which performs crystallization extraction of uranium from a nitric acid solution of uranyl nitrate during... 相似文献
58.
Nina Kobal Tjaa Kraovec Maja utar Marija Volk Borut Peterlin Marko Hawlina Ana Fakin 《International journal of molecular sciences》2021,22(4)
Mutations in rhodopsin gene (RHO) are a frequent cause of retinitis pigmentosa (RP) and less often, congenital stationary night blindness (CSNB). Mutation p.G90D has previously been associated with CSNB based on the examination of one family. This study screened 60 patients. Out of these 60 patients, 32 were affected and a full characterization was conducted in 15 patients. We described the clinical characteristics of these 15 patients (12 male, median age 42 years, range 8–71) from three families including visual field (Campus Goldmann), fundus autofluorescence (FAF), optical coherence tomography (OCT) and electrophysiology. Phenotypes were classified into four categories: CSNB (N = 3, 20%) sector RP (N = 3, 20%), pericentral RP (N = 1, 6.7%) and classic RP (N = 8, 53.3% (8/15)). The phenotypes were not associated with family, sex or age (Kruskal–Wallis, p > 0.05), however, cystoid macular edema (CME) was observed only in one family. Among the subjects reporting nyctalopia, 69% (22/32) were male. The clinical characteristics of the largest p.G90D cohort so far showed a large frequency of progressive retinal degeneration with 53.3% developing RP, contrary to the previous report. 相似文献
59.
Unlike classically defined insertion sequence (IS) elements, which are delimited by their inverted terminal repeats, some IS elements do not have inverted terminal repeats. Among this group of atypical IS elements, IS116, IS900, IS901, and IS1110 have been proposed as members of the IS900 family of elements, not only because they do not have inverted terminal repeats but also because they share other features such as homologous transposases and particular insertion sites. In this study, we report a newly identified IS sequence, IS1547, which was first identified in a clinical isolate of Mycobacterium tuberculosis. Its structure, insertion site, and putative transposase all conform with the conventions of the IS900 family, suggesting that it is a new member of this family. IS1547 was detected only in isolates of the M. tuberculosis complex, where it had highly polymorphic restriction fragment length polymorphism patterns, suggesting that it may be a useful genetic marker for identifying isolates of the M. tuberculosis complex and for distinguishing different strains of M. tuberculosis. ipl is a preferential locus for IS6110 insertion where there are eight known different insertion sites for IS6110. Surprisingly, the DNA sequence of ipl is now known to be a part of IS1547, meaning that IS1547 is a preferential site for IS6110 insertion. 相似文献
60.
A periodic linear measure is described for use in scanning electron microscopes, which has eight values for line width in
the micrometer and submicrometer ranges. Methods have been developed for calibrating the SEM with such a measure, which are
not sensitive to errors in beam focusing.
Translated from Izmeritel'naya Tekhnika, No. 4, pp. 48–52, April, 2000. 相似文献