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81.
P. Sharma M. Bose Isa Mohd S. Bagdi H. G. Raj 《Indian journal of clinical biochemistry : IJCB》2000,15(2):83-87
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned
fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment.
Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted
in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study. 相似文献
82.
A seven channel polystyrene (PS) microchip has been constructed using a micromilling machine and a high-temperature assembling. Protein A (PA) has been immobilized by a passive sorption on the microchannel walls. Two bioaffinity assays with human immunoglobulin G (hIgG) as a ligand have been carried out. (i) PA as the receptor and fluorescently labeled hIgG (FITC-hIgG) as the ligand, (ii) PA as the receptor with hIgG as the quantified ligand and fluorescently labeled goat anti-human IgG (FITC-gIgG) as the secondary ligand. One incubation step of the assays took only 5 min instead of hours typical for enzyme-linked immunosorbent assay applications. Calibration curves of the dependence of a fluorescence signal on the hIgG concentration in a sample have been obtained in one step due to a parallel arrangement of microchannels. A mathematical model of the PA-FITC-hIgG complex formation in the chip has been developed. The values of the kinetic constant of the PA-FITC-hIgG binding (kon=5.5 m3 mol−1 s−1) and the equilibrium dissociation constant of the formed complex (Kd≤3×10−6 mol m−3) have been obtained by fitting to experimental data. The proposed microchip enables fast evaluation of kinetic and equilibrium constants of ligand-receptor bioaffinity pairs and the ligand quantification. As the use of microfluidic chips for immunoassays is often limited by price, we used procedures and chemicals that allow for an inexpensive construction and operation of the microdevice, e.g., temperature assembling as a fabrication technique, detection via an ordinary digital camera, nonspecific polystyrene as a substrate, passive sorption of biomolecules as an immobilization technique, etc. 相似文献
83.
84.
汽车传感器和车载网络技术是汽车类专业的一门拓展应用能力的课程,包含了传感器和网络技术两方面的知识,具有知识量大、理论性强、课程各单元关联性差等特点。为了适应应用型汽车专业发展的需要,以提高学生学习兴趣、降低课程难度为目标,从教学内容、教学方法、课程资源建设和课程考试方案等方面对课程的改革措施进行探讨,改变以往重理论、重基础、轻实践和应用的教学模式。 相似文献
85.
分析了自动化类等相关专业嵌入式系统设计课程教学中存在的问题,进而对该课程的教学方法、教学手段、考核方式进行了改革和实践。在该课程的教学中引入慕课等线上资源,充分利用微信教学立方等现代教学手段进行课堂互动,并通过"任务驱动+项目导向"的教学模式督促学生自主完成学习任务。 相似文献
86.
As the American population continues to become more diverse there is a need to provide children in early education with factual information about all ethnic groups to decrease prejudice. First, teachers must examine their own beliefs prior to implementing a multicultural approach into the curriculum. Three questions are presented that will assist teachers in evaluating their views and behaviors toward ethnic groups. Informative resources are provided for teachers to educate themselves, parents, and students. Through children's literature, instructional materials, and Internet sources, teachers can promote more positive attitudes among students and educate children to be respectful and accept the individuality of others. 相似文献
87.
Treatment practices for childhood posttraumatic stress disorder 总被引:4,自引:0,他引:4
OBJECTIVE: This study surveyed practices in treating childhood PTSD among child psychiatrists and non-M.D. therapists with self-identified interest in treating traumatized children. METHOD: An anonymous survey was mailed to 207 child psychiatrists ("medical") and 460 nonphysician ("non-medical") therapists inquiring about current interventions used to treat children with PTSD. RESULTS: Two hundred and forty-seven responses were received: of 77 medical and 82 nonmedical respondents who currently treat children with PTSD, a wide variety of modalities are used. Most preferred modalities among medical responders were pharmacotherapy, psychodynamic, and cognitive-behavioral therapy. Most preferred modalities among nonmedical respondents were cognitive-behavioral, family, and nondirective play therapy. Ninety-five percent of medical respondents used pharmacotherapy for this disorder; most preferred medications to treat childhood PTSD were selective serotonin reuptake inhibitors and alpha-adrenergic agonists. Several significant differences between medical and nonmedical practices were identified. CONCLUSIONS: There is little clinical consensus regarding the effectiveness of the many modalities used to treat traumatized children who have PTSD symptoms; empirical research is particularly needed to evaluate the efficacy of pharmacotherapy and EMDR. 相似文献
88.
《中国教育现代化2035》明确提出,教育向社区开放,政府投入、社会捐赠、学习者合理分担是社区教育经费来源的主渠道,政府投入列在首位,然而西部民族地区政府投入不足,不能很好地满足社区教育发展的需求.通过分析西部民族地区社区教育政府投入现状,提出"中央与地方财政事权和支出责任划分,建立科学稳定的经费核拨下达制度""将社区教育经费支出纳入政府部门预决算""优化教育经费内部结构""指明社区教育责任和实施主体"等发展路径,助力社区教育在西部民族地区均衡发展. 相似文献
89.
90.
Bacca-Acosta Jorge Tejada Julian Fabregat Ramon Kinshuk Guevara Juan 《Educational technology research and development : ETR & D》2022,70(1):339-362
Educational technology research and development - Scaffolding is a mechanism for helping novice learners to solve a problem or complete a task that is beyond their current skill set. Prior research... 相似文献