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171.
以1-(3-二甲氨基丙基)-3-乙基碳二亚胺(简称EDCI)为缩合剂对丝素改性胶原膜进行了肝素固定化,用X光电子能谱分析了材料的表面性质. 测定了固定化肝素的量并研究了固定化肝素的稳定性. 结果表明固定化肝素量为2.34μg/cm-2,体外释放试验表明肝素量虽有下降但有较好的稳定性. 相似文献
172.
周玲 《张家口职业技术学院学报》2005,18(4):6-10
清代著名学者阮元,创办了新式书院诂经精舍和学海堂,旨在培养有"经世致用"、对社会有用的人才.书院提倡德才兼备;主张因材施教,自由探讨;强调实事求是,学以致用;学术研究和教学相结合;确立破旧立新、推举学长的教学体制.倡导了实践,培养了学生的实际能力.阮元的教育思想和实践对清末的教育界产生了深远的影响,为中国的教育事业做出了突出的贡献. 相似文献
173.
The performance of speaker verification systems is often compromised under real-world environments. For example, variations in handset characteristics could cause severe performance degradation. This paper presents a novel method to overcome this problem by using a non-linear handset mapper. Under this method, a mapper is constructed by training an elliptical basis function network using distorted speech features as inputs and the corresponding clean features as the desired outputs. During feature recuperation, clean features are recovered by feeding the distorted features to the feature mapper. The recovered features are then presented to a speaker model as if they were derived from clean speech. Experimental evaluations based on 258 speakers of the TIMIT and NTIMIT corpuses suggest that the feature mappers improve the verification performance remarkably. 相似文献
174.
在pH=9.0 H3BO3-Na2B4O7缓冲体系中,以5-溴水杨醛甘氨酸修饰碳糊电极为工作电极,Cu2 于 120mV(vs.SCE)处产生一灵敏的吸附波,其二阶导数峰电流与Cu2 浓度在4.0×10-9~8.0×10-7mol.dm-3范围内呈良好的线性关系,相关系数为0.9964,检出限为6.0×10-10mol.dm-3(3倍信噪比)。应用该法测定发样中Cu2 的含量,结果令人满意。 相似文献
175.
陈英杰 《三门峡职业技术学院学报》2007,6(3):1-4
本文从世界高等教育发展史、我国高等职业教育发展史和我国学位制度的演变说明高等职业教育是一种类型,并对今后我国职业教育的发展从认识上、制度上、具体办学上相应提出了建议。 相似文献
176.
Limeng Liang 《International Journal of Disability, Development & Education》2016,63(3):369-383
This article reports on a mixed-method inquiry into pre-service and in-service secondary school teachers’ knowledge about Attention-deficit Hyperactivity Disorder (ADHD) and attitudes toward students with this disorder in Hong Kong. The inquiry revealed no differences between pre-service and in-service secondary school teachers concerning their knowledge of ADHD and attitudes toward students with ADHD. It also identified possible sources of participants’ knowledge and a variety of factors underlying their attitudes toward students with ADHD including sociocultural beliefs and working conditions. The findings call for teacher educators to develop better education programmes to support both pre-service and in-service teachers in undertaking the challenging task of teaching students with ADHD. 相似文献
177.
Raymond M. Klein 《Reading and writing》2002,15(1-2):207-231
The definitions of developmental dyslexia andtemporal processing are discussed and severalconstruals of what a temporal processingdeficit might entail are illustrated. Then,using a framework developed by Farmer & Klein(1995), the proposal that a temporal processingdeficit (in vision, audition, or both) might bethe root cause of some proportion of cases ofdevelopmental dyslexia is introduced andvarious research strategies for testing thisproposal are identified. The symposium paperswhich address this general question using arange of these strategies are then criticallyreviewed. It is noted that whereas reading isa recent artifact not yet subject to any directselection pressure, its normal performancerequires the use of, and connections between,the highly evolved modules for visual patternrecognition and language. Within vision andlanguage redundant coding, which permitsperformance in the face of injuries anddegraded input, also makes it difficult todetect subtle deficits (whether temporal, ornot) unless precise tests are used. Yet suchdeficits may degrade performance on tasks (suchas reading) which require the non-copiousconnections between vision and language. Theefficacy of this pathway, I suggest, ismeasured by performance on the rapidautomatized naming (RAN) test. 相似文献
178.
目的:探讨热休克蛋白70(HSP70)在人乳腺癌和胃癌中的表达及其意义。方法:应用免疫组织化学的方法对64例乳腺癌和55例胃癌组织中的HSP70进行检测。结果:(1)HSP70在乳腺癌和胃癌组织中的表达分别为78.13%.61.82%。(2)乳腺癌中HSP70的表达与乳腺癌的病理类型.淋巴结转移情况及年龄未发现显著差异(P〉0.05)。(3)胃癌中HSP70的表达与肿瘤浸润深度、淋巴结转移有密切关系(P〈0.05)。结论:HSP70在乳腺癌和胃癌中均呈较高水平表达.其中在胃癌中的表达与肿瘤浸润深度、恶性程度有密切关系,HSP70在乳腺癌和胃癌的发生发展中起重要作用。HSP70可能成为乳腺癌,胃癌的诊断指标之一。 相似文献
179.
180.
At present ,during the design of ground source heatpump (GSHP) systems ,technical attention is always fo-cused on vertical borehole heat exchangers and surroundingsoil[1 ,2],butthe effects of their shallowhorizontal connect-ing pipes ,or horizontal ground… 相似文献