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排序方式: 共有49条查询结果,搜索用时 373 毫秒
11.
This paper studies on fabrics suitable for child patients'garment in the hospital environment in Hong Kong,China.Subjective measurement was carried out by questionnaire survey to consult medical staff on hospital requirement about fabric criteria for child patients' garment. On the other hand, objective measurement was conducted by performing laboratory tests on fabrics,which were sourced from commercial fabric market. Both measurements are evaluated according to the results on those fabric criteria in order to determine the most suitable kind of fabric for the end purpose. As a result of the comparison, it was found that T/C 1 scores the highest index. Therefore, it will be suggested for manufacturing child patients' garment to evaluate the fabric suitability to meet the wearers' requirement through hospital trial.  相似文献   
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This paper described the physical behaviour of three types of denim cloths produced from rotor yarn, ring yarn and modified rotor yarn (prepared by adding conventional twist to rotor yarn) respectively. Experimental work showed that denim cloth produced from the modified rotor yarn has superior properties over conventional rotor yarn in terms of surface texture and appearance,tearing strength and resistance to abrasion.  相似文献   
13.
Magnetic fluid-assisted finishing has been verified both theoretically and experimentally as an effective fabrication technology for optical mirrors and lenses. The purpose of this paper is to introduce a novel design of polishing tool and demonstrate the possible applications of this technology. The work includes studying the viscosity of the magnetic suspensions of micrometer-sized Carbonyl iron particles under the influence of a magnetic field. Both the cases of magnetizable suspension with and without abrasive cerium oxide particles are studied for their ensuing polishing effectiveness. Determination of material removal function is conducted using a Wyko Nat1100 interferometer. Experiments to reduce surface roughness with the proposed tool are also performed using a K9 mirror as the work-piece. Results show that the surface accuracy is improved over three times to less than 0.5 nm after two cycles of polishing.  相似文献   
14.
Y C Wong  P Y Wong  C H Yeung 《Experientia》1978,34(4):485-487
Electron microscopic study was made on the water reabsorption of the epithelial cells of the rat cauda epididymidis. It was shown that when the epididymal duct was reabsorbing water at a maximal rate, widely dilated intercellular spaces were seen. It is suggested that the standing gradient model of water reabsorption first proposed for the gall bladder may also operate in the cauda epididymidis.  相似文献   
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研究在转杯纺加捻区中加装阻扭件,然后选用相同的棉条纺制不同捻系数的转杯纱(加装阻扭件和不加装阻扭件)和环锭纱,并测试其成纱的强伸性能、表面形态和扭转性能.测试结果表明,加装阻扭件的转杯纱可以适当改善转杯纺的加捻效果,进而适当提高了转杯纱的成纱强力.  相似文献   
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The gastrointestinal epithelium is a highly organised tissue that is constantly being renewed. In order to maintain homeostasis, the balance between intestinal stem cell (ISC) self-renewal and differentiation must be carefully regulated. In this review, we describe how the intestinal stem cell niche provides a unique environment to regulate self-renewal and differentiation of ISCs. It has traditionally been believed that the mesenchymal myofibroblasts play an important role in the crosstalk between ISCs and the niche. However, recent evidence in Drosophila and in vertebrates suggests that epithelial cells also contribute to the niche. We discuss the multiple signalling pathways that are utilised to regulate stemness within the niche, including members of the Wnt, BMP and Hedgehog pathways, and how aberrations in these signals lead to disruption of the normal crypt–villus axis. Finally, we also discuss how CDX1 and inhibition of the Notch pathway are important in specifying enterocyte and goblet cell differentiation respectively.  相似文献   
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Effect of UV-B radiation on ingesting and nutritional selecting behavior of the roifer Brachionus urceus on 5 species of microlgae were studied under controlled laboratory conditions. Restdts showed that enhanced UV-B radiation significantly inhibited ingesting of the rotifer B. urceus when it was fed with 5 species of micro-algae (p〈0.05). The ingesting selectivity rate varied with the UV-B radiation enhancement when it was fed with 5 species micro-algal mixture. Results indicated that the enhanced UV-B radiation could affect ingesting and nutritional selectivity of B. urceus.  相似文献   
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Summary -Glutamylcysteine synthetase is present in barely detectable amounts in foetal kidney. Its activity starts to increase in postnatal life. In contrast, oxoproline is already found in significant quantities in the foetal tissue. Both enzymes show marked elevation in activities during the weaning period.Acknowledgment. The work was supported by a research grant awarded by the Committee on Research and Conference Grants, University of Hong Kong.  相似文献   
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