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61.
目的:设计研制一个面向院校电教中心的多媒体数据库管理系统,以便用现代信息技术管理电教中心众多的信息资料。方法:在国产MIS开发平台Multibase2.0上,用原型法进行无编程设计开发。结果:制作的数据库管理系统运行稳定,操作方便,维护简单,查询功能新颖而强大,基本功能设计具有较强的针对性,能够满足电教中心日常工作的需要。结论:采用国产无编程MIS开发平台Multibase完全可以开发出实用的多媒体数据库管理系统,本数据库管理系统可向军内外院校推广使用。 相似文献
62.
A comparison of gait initiation and termination methods for obtaining plantar foot pressures 总被引:2,自引:0,他引:2
The midgait protocol is the most commonly used method to collect pressure platform data. Spatial limitations, however, frequently render this technique unsuitable. Alternative gait protocols have focused on gait initiation procedures in obtaining data. The current study investigated whether a commonly cited two-step gait initiation protocol, or a two-step gait termination protocol produced pressure data more representative of the criterion, midgait method. A pressure platform was used to collect data for 25 asymptomatic subjects using the midgait, two-step gait initiation and two-step gait termination walking protocols. The contact duration, percentage contact duration, peak pressure, peak force, pressure–time integral and force–time integral were calculated for seven sites within the foot. Multivariate analysis of variance with repeated measures identified significant protocol by site interactions for all variables except the force-time integral. The gait initiation protocol, although having minimal effect on peak pressures beneath the forefoot, markedly altered the relative timing parameters of the foot. In contrast, the gait termination protocol had minimal effect on temporal parameters, but resulted in a reduction in pressures beneath the forefoot. Abbreviated gait protocols are often employed in plantar pressure studies. This study suggests that the choice between a gait initiation and termination protocol is largely dependent on the gait parameter of interest. 相似文献
63.
Does subclinical rejection contribute to chronic rejection in renal transplant patients? 总被引:6,自引:0,他引:6
Rush DN Karpinski ME Nickerson P Dancea S Birk P Jeffery JR 《Clinical transplantation》1999,13(6):441-446
Renal allograft biopsies have traditionally been performed in the setting of acute graft dysfunction. However, several groups have performed graft biopsies at times of stable graft function, and more recently, after treatment of rejection episodes. Surprisingly, unequivocal histologic criteria for acute rejection have been demonstrated in a high proportion of these protocol biopsies. The Winnipeg Transplant Group has documented the high prevalence of clinically silent inflammatory infiltrates in early protocol biopsies, and demonstrated their inflammatory and cytotoxic potential by immunohistochemical and molecular biological techniques. Furthermore, in a randomized trial, our group has demonstrated that subclinical rejection, if untreated, is associated with the development of early chronic pathology and late graft dysfunction. In this overview, we will summarize the early data on subclinical allograft inflammation, present the experience of the Winnipeg Transplant Group, and discuss the possible implications of subclinical rejection on the development of chronic rejection. 相似文献
64.
OBJECTIVES: The University of Natal Medical School in South Africa provides training for a student body composed of two groups: one with English as a first language and the other with an African language as a first language and English as the second. A new methodology was developed to evaluate an innovative course using modified problem-based learning techniques in this heterogeneous environment. DESIGN: The learning model proposed required achieving a balance of three components: content, enquiry/learning process and social interaction/group process. A multidimensional system, felt to be consistent with this educational philosophy, was developed using seven different quantitative and qualitative techniques. SETTING: The University of Natal Medical School. SUBJECTS: First-year multilingual medical students. RESULTS: The results revealed that social interaction was highly successful in reducing barriers between the student groups and between students and facilitators. However, the emphasis on group participation may have overshadowed the enquiry process, leading to superficial discussions of problems and feelings of repetitiveness. During the course students and facilitators expressed concern that the innovative assessments used did not assess the course content adequately. While the group presentations and projects were useful exercises for consolidation and group interaction, they did not enable facilitators to identify struggling students. CONCLUSIONS: The outcome of the evaluation stressed the need of achieving an appropriate balance both in the curriculum and assessments of the three components of the learning model, particularly in a setting where student backgrounds and language ability differ. Multidimensional methodology is needed for effective evaluation that promotes critical reflection. 相似文献
65.
Evaluating the mutagenic potential of chemicals the minimal battery and extrapolation problems 总被引:1,自引:0,他引:1
F. H. Sobels 《Archives of toxicology》1980,46(1-2):21-30
During the past ten years growing concern about damage to DNA as an important cause of human ill-health has resulted in an explosive development of the field of genetic toxicology. Adequate regulations to restrict exposure to chemical mutagens require recognition and evaluation of mutagenic activity. For this purpose a qualitative and an extrapolation phase can be distinguished. For the qualitative phase, the minimal battery should consist of at least three tests, that is: (1) tests for gene- or point mutations in bacteria (Salmonella or E. coli) with and without metabolic activation; (2) two tests for point mutations in eukaryotes, or (3) one such test and a test for the detection of chromosome aberrations in mammalian cells in vitro. Depending on experience and facilities, a choice of two can be made out of the following four test systems: (1) Tests for point mutations in mammalian cells in vitro, with and without metabolic activation (deficiency for HGPRT, or TK); (2) the sex-linked recessive lethal test with Drosophila melanogaster; (3) tests with yeast, Saccharomyces cerevisiae, for point mutations, with and without metabolic activation; (4) tests for chromosome aberrations in mammalian cells in vitro, with and without metabolic activation. Two different metabolic activation systems should be employed. For further selection of more sensitive test systems, studies on comparative mutagenesis are considered important. A mammalian test for chromosome aberrations in vivo is not included in this minimal battery. Since under in vivo conditions considerably lower concentrations have to be employed than in vitro, it seems unlikely that positive results will be obtained with an in vivo mammalian cytogenetic assay, following negative results in an in vitro cytogenetic assay or in two different tests for point mutations. The finding that the effective concentration for the production of chromosome breakage events differs from that required to induce point mutations (the two-level effect) will be briefly discussed. When mutagenic compounds are indispensible or, in the case of ubiquitous exposure, a quantification of risks becomes necessary and here one is confronted with many difficulties. Information on damage that is hard to measure directly can be obtained in an indirect way by comparison with end-points that can be determined experimentally, such as alkylation per nucleotide.
Names of chemical substances tested: hydroxylamine; diepoxybutane; N-ethyl-N-nitrosourea; methylmethanesulfonate (MMS); DEN; Mitomycin C; Procarbazine; atrazine; benz(a)pyrene; EMS; pyrolitic products; flavonoids; mycotoxins; nitrosamines; TEMGiven at the International Conference Mutagenicity Testing of Pharmaceuticals: Present Status, Paris, 12–14 March, 1980, sponsored by the Fondation de l'Industrie Pharmaceutique pour la Recherche 相似文献
66.
全盆四野加速超分割放射治疗Ⅲb期子宫颈鳞癌的临床研究 总被引:8,自引:0,他引:8
探讨全盆四野加速超分割放射治疗晚期子宫颈癌的临床价值。方法:于1998年1月至1999年10月分别采用全盆二野常规分割标准方案(CF组,18例)和全盆四野加速超分割方案(AHF组,17例),治疗Ⅲb期子宫颈鳞癌,对放射不良反应和治疗效果进行临床比较研究。结果:1)AHF组全疗程平均40.1天完成,CF组平均57.3天完成,AHF组疗程显著短于CF组(P<0.01);2)AHF组2、3年生存率分别为88.2%、82.4%,CF组分别为83.3%、72.2%,前者有提高生存率的趋势,但差异无统计学意义(P>0.05);3)AHF组3年局部控制率(94.1%)高于CF组(77.8%),AHF组有提高肿瘤局部控制率的趋势,但两组差异无统计学意义(P>0.05);4)近期放疗反应两组第一位均为直肠反应,其次是膀胱反应,差异无统计学意义(P>0.05);远期放疗反应第一位为照射野皮下纤维化,AHF组发生率(5.9%)显著低于CF组(72.2%)(P<0.01),两组直肠、膀胱反应发生率差异均无统计学意义(P>0.05)。结论:当采用60Co体外照射时,全盆四野加速超分割方案与常规分割标准方案比较,有提高ⅢΒ期子宫颈鳞癌生存率及局部控制率的趋势,具有总疗程明显缩短,不增加近期放疗不良反应,可显著减少远期照射野皮下纤维化的发生等优点,值得推广。 相似文献
67.
Attentional Difficulties in Middle Childhood and Psychosocial Outcomes in Young Adulthood 总被引:8,自引:0,他引:8
David M. Fergusson Michael T. Lynskey L. John Horwood 《Journal of child psychology and psychiatry, and allied disciplines》1997,38(6):633-644
The associations between (dimensionally scored) measures of attentional difficulties at age 8 and psychosocial outcomes at age 18 were examined in a birth cohort of New Zealand children. Increasing attentional difficulties during middle childhood were associated with increased risks of academic failure or difficulties, juvenile offending, and substance use behaviours in young adulthood. However, those with early attentional difficulties were a high-risk group characterised by social disadvantages, early conduct difficulties, lower 1Q, and related characteristics. Statistical adjustments showed: (a) that attentional difficulties were related to later academic success even when due allowance was made for potentially confounding factors; and (b) early attentional difficulties were unrelated to later juvenile offending or substance use behaviours after adjustment for confounding. In all cases there was evidence of consistent dose/response relationships between the extent of early attentional difficulties and later academic outcomes, suggesting that these associations were not confined to those with extreme symptoms. 相似文献
68.
钱晓勤 《南通大学学报(哲学社会科学版)》2000,(2)
朱熹的教育思想十分丰富 ,其“明人伦”、“教有成法”、居敬持志等教育思想对我们今天教育学生学会做人、培养学生创新能力有重要的现实指导意义 相似文献
69.
目的:探讨端粒酶在卵巢癌发 生和发展中的作用,及端粒酶活性与临 床病理因素的相关性。方法:应用端粒 重复序列扩增技术(TRAP)检测45例卵 巢上皮性肿瘤及9例正常卵巢组织端粒 酶活性。结果:端粒酶阳性检出率在恶 性和交界性卵巢肿瘤组中分别为 83.33%(25/30)和5/7,差异无统计学意 义,P=0.5963;良性上皮性卵巢肿瘤及 正常卵巢上皮组织中未检测到端粒酶活 性,与前两组之间均差异有统计学意义 P<0.01。端粒酶的表达与临床病理因 素无明显相关性。结论:端粒酶在卵巢 癌发生和发展过程中可能具有重要作 用,并有望作为卵巢上皮性癌基因治疗 的靶点。 相似文献
70.
K. Whelan J. E. Thomas S. Cooper† R. Hilton‡ S. C. Jones§ T. Newton¶ B. O'Neill & E. E. Gill 《Journal of human nutrition and dietetics》2005,18(6):461-466
BACKGROUND: Interprofessional education (IPE) is a novel teaching and learning initiative where students of more than one health profession learn interactively together. However, despite its potential for improving interprofessional relationships, there is little information regarding the participation of student dietitians in IPE. The aim of this paper was to consider the reaction of student dietitians to an IPE course in order to stimulate debate between dietitians regarding the issues relating to IPE. METHODS: Student dietitians participated in an IPE course consisting of seven sessions on communication and ethics in health care together with students of medicine and nursing. Student dietitians completed an evaluation questionnaire following each session that surveyed their reaction to the session using both a Likert scale and free-text comments. RESULTS: Twenty-six student dietitians completed the IPE course. All sessions were rated positively for interest value (P < or = 0.14), learning experience (P < or = 0.036) and value for clinical practice (P < or = 0.05). The limited number of free-text comments indicated some positive experiences regarding interprofessional learning, teaching content and teaching strategy. CONCLUSIONS: This is one of very few evaluations to describe the reaction of student dietitians to IPE. Student dietitians had largely positive reactions to the IPE course. Further research is required to evaluate whether these positive reactions were a direct consequence of the inclusion of students from other health professions and whether these translate into positive effects on learning, behaviour and results. The opportunities for the dietetic profession posed by students' involvement in IPE are discussed. 相似文献