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1.
《Journal of pharmaceutical sciences》2019,108(11):3515-3520
Particle size analysis in the pharmaceutical industry has long been a source of debate regarding how best to define measurement accuracy; the degree to which the result of a measurement or calculation conforms to the true value. Defining a “true” value for the size of a particle can be challenging as the output of its measurement will differ because of variations in measurement approaches, instrumental differences and calculation methods. Consequently, for “real” particles, a universal “true” value does not exist and accuracy is therefore not a definable characteristic. Accordingly, precision is then a measure of the ability to reproducibly achieve a measurement of unknown relevance.This article proposes, in place of accuracy, a means to define the “appropriateness” of a measurement in line with the critical quality attributes (CQA) of the material being characterized. The decision as to whether the measurement is correct should involve a link to the CQA; that is, correlation should be demonstrated, without which the measured particle size cannot be defined as a critical material attribute.Correspondingly, methods should also be able to provide sufficient precision to demonstrate discrimination relating to variation in the CQA. The benefits and challenges of this approach are discussed. 相似文献
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医用低值材料采供管理的探讨 总被引:4,自引:2,他引:2
医疗消耗材料是医疗工作开展的基础,本文从医用低值消耗材料的计划制定、材料采购、库房库存结构、材料供应、成本核算等多方面探讨了如何对医疗消耗材料进行科学管理,这对医院的医疗发展和管理建设有着重要意义。 相似文献
5.
Industrial back belts and low back pain: Mechanisms and outcomes 总被引:1,自引:0,他引:1
The recent increased utilization of industrial back belts as personal protective equipment in the workplace has generated considerable controversy among occupational health and safety professionals in the United States. The purpose of this article is to review the literature regarding proposed mechanisms of action of these devices and studies related to outcome of belt utilization in the prevention of low back pain and disability in the workplace. At the present time, neither the suspected mechanisms of action nor the efficacy of these devices in the primary, secondary, and tertiary prevention of work-related low back pain has been adequately demonstrated in clinical trials. As a result, generally accepted guidelines regarding the safe use of belts in the occupational setting have not been established. Based on this review it is recommended that further well-controlled, prospective, randomized clinical trials are necessary to evaluate the effectiveness of these devices as personal protective equipment. During the interim, the decision to prescribe belts to employees in the workplace should be at the discretion of an adequately trained occupational health care provider. These devices should not be provided as an alternative to appropriate administrative and/or engineering controls. 相似文献
6.
本文主要研究了无机玻璃纤维增强聚甲基丙烯酸甲酯(PMMA)/羟基磷灰石(HA)复合材料的制备及相关的性能测试,证明此复合材料性能稳定、物理机械强度高以及工艺简单,有良好的应用前景。 相似文献
7.
In this paper an uncomplicated method for the simultaneous detection and semiquantitation of 11 of the 12 commonly studied antinuclear antibodies (ANA) in a single run is described. This new application of checkerboard immunoblotting (CBIB) is based upon available technology and employs purified antigens which can be either purchased or produced in-house. CBIB requires no electronic instrument, can be formatted to meet the needs of the user, is rapidly performed, and has acceptable labor and materials costs. Data on the use of the method to examine available reference antisera is presented. CBIB has also proven practical for the clinical study of 18 sera, at two dilutions per membrane, for each set of specific antinuclear antibodies, also at two or more dilutions. 相似文献
8.
颌面赝复材料研究进展 总被引:5,自引:0,他引:5
赵信义 《国际生物医学工程杂志》2006,29(3):178-183
综述了目前口腔颌面赝复材料种类、性能要求及各种颌面赝复材料的组成、性能和应用过程,探讨了各种颌面赝复材料的优势及不足,指出目前临床应用的颌面赝复材料以硅橡胶类为主,其中又以中温硫化硅橡胶和室温硫化硅橡胶综合性能较好,应用最为广泛。 相似文献
9.
L Ho-Terry G M Terry P Londesborough K R Rees F Wielaard A Denissen 《Journal of medical virology》1988,24(2):175-182
The efficacy of nucleic acid hybridization for the diagnosis of rubella infection in experimental and clinical materials was compared with immunoblot and virus isolation techniques. Our results showed that nucleic acid hybridization is specific and rapid but gives false-negative results when compared with conventional virus isolation in some experimental although not in clinical materials so far examined. For this reason, a failure to demonstrate rubella virus in fetal specimens by this method alone cannot yet be taken as a sole criterion for ruling out fetal rubella infection. 相似文献
10.
R. J. REID P.V. ABBOTT J. R. MCNAMARA G. S. HEITHERSHAY 《International endodontic journal》1992,25(4):213-220
A prospective clinical and radiographic study was conducted in order to compare Hydron and laterally condensed gutta-percha/AH-26 root canal fillings. Paralleling technique periapical radiographs were taken preoperatively, postoperatively and at recall appointments at post-treatment intervals of 6 months, 1 year, 2 years, 3 years and 5 years. Clinical examination at the recall appointments revealed no adverse signs or symptoms amongst all the patients who attended (mean attendance 44.5% at each interval). Radiographs were scored according to the periapical status of the treated root, and comparable bone healing rates were observed between the two root-filling materials. Among the patients attending recall appointments, there were no radiographic signs of failure of any of the 39 gutta-percha/AH-26 root canal fillings. However, three of the 35 canals filled with Hydron were classified as failures, and four required further assessment after the 5-year recall appointment. This study indicated that Hydron and gutta-percha/AH-26 root canal fillings were well accepted but, on the basis of radiographic assessment, success with gutta-percha/AH-26 was more predictable. 相似文献