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81.
病原生物学多媒体网络互动教学实验室的建设与展望 总被引:5,自引:0,他引:5
介绍了病原生物学多媒体网络互动教学实验室的建设和应具备的功能 ,论述了多媒体互动网络的建成对病原生物学实验教学环境和实验教学效果的积极促进作用 ,并对实验室以后的发展方向进行了展望 相似文献
82.
师爱枝 《山西职工医学院学报》2004,14(4):9-10
目的:观察危重型肾功能衰竭合并高危出血患者选择抗凝药物进行血液透析治疗的效果。方法:应用吉派林(低分子肝素钠)作为抗凝剂进行血液透析。结果:129例病人进行血液透析386次,均没有出血发生。结论:吉派林在高危出血患者血液透析中使用方便,安全,效果良好。 相似文献
83.
Meiosis was examined in pollen mother cells of F1 hybrids made from crosses between wheat (Triticum aestivum) and lymegrass (Leymus arenarius and L. mollis). Fluorescence genomic in situ hybridization detected pairing between wheat and lymegrass chromosomes during prophase I and metaphase I. Such pairing, when resulting in bivalent formation, was likely to yield correct disjunction, and hence intergenomic recombination could be incorporated into the gametes. Bivalents in these hybrids, however, were more frequently formed between chromosomes of the same parental origin. Univalents were common, whereas multivalents were not clearly detected. Meiotic behaviour in some cells was not totally aberrant, and this may have accounted for the presence of normal pollen. The results are discussed in relation to intergenomic pairing, meiotic behaviour in wide-hybrids and genome relationships, including the Leymus genome origin. 相似文献
84.
目的 探索如何抑制嗜酸细胞的趋化作用,选择β-趋化因子巨噬细胞炎性蛋白4(MIP4)的突变性(Met-MIP4)作为趋化因子受体3的拮抗剂,将Met-MIP4基因在原核细胞中进行表达。方法 设计MIP4基因的PCR引物并进行氨基酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸,以正常人肺酸突变,将MIP4N末端的丙氨酸突变为蛋氨酸。以正常人肺cDNA文库为模板,PCR方法获取Met-MIP4基因,克隆入载体pUC19,测序验证序列已得到突变,将正确的基因插入到GST融合表达载体pGEX-4T中,以IPTG诱导表达。结果 PCR产物为220bp左右的片段,连接入pUC19质粒后测序验证获得正确突变,构建的pGEX-4T融合表达载体在大肠杆菌中表达,经SDS-PAGE凝胶电泳显示有大小约34kU的新生融合蛋白表达。结论 成功突变并克隆了β-趋化因子MIP4基因,SDS-PAGE表明,与GST融合的Met-MIP4突变体已得到表达,为进一步研究其生物学活性奠定了基础。 相似文献
85.
J. Harro Charlotta Löfberg Rein Pähkla Vallo Matto Lembit Rägo Lars Oreland Lembit Allikmets 《Naunyn-Schmiedeberg's archives of pharmacology》1996,355(1):57-63
Cholecystokinin (CCK) is a neuropeptide recently implicated in affective disorders. This study aimed at measuring the levels
of different molecular forms of CCK and the binding characteristics of CCKB receptors in the rat brain after three weeks of treatment with four different antidepressants, imipramine, amitriptyline,
desipramine, and citalopram (all at the dose of 10 mg/kg once per day i.p.). Chronic treatment with imipramine and desipramine
had a significant immobility-reducing effect in the Porsolt‘s swim test. The effect of amitriptyline, albeit in the same direction,
was not significant, and citalopram had no effect in this test. In the elevated plus-maze test of anxiety, all drugs tended
to increase the number of open arm entries and the ratio open/total arm entries, but only the effects of imipramine were statistically
significant. None of the treatments affected the total levels of CCK or the levels of CCK-8-sulphated, CCK-8-nonsulphated,
CCK-5, or CCK-4 in the frontal cortex. There was no effect of the treatments on CCKB receptor binding in the frontal cortex, hippocampus, or striatum. Imipramine and amitriptyline, however, increased the affinity
of CCKB receptor binding in the hypothalamus. Thus, no consistent effect of chronic antidepressant treatment on the CCK-ergic neurotransmission
in the rats was found.
Received: 4 June 1996 / Accepted: 26 August 1996 相似文献
86.
Molecular staging of head and neck squamous carcinoma 总被引:3,自引:0,他引:3
The staging system of head and neck cancer is a Tumor-Node-Metastases system that was developed by the American Joint Committee on Cancer. The stage of the head and neck cancer defines the extent of the lesion and is determined by physical examination, radiologic studies, and pathologic examination. Accurate staging of head and neck cancer is critical since it will determine the treatment modalities used to cure the disease. Recent advances in the field of molecular genetics have allowed clinicians to detect occult cancer cells previously missed by physical examination and standard histopathologic techniques. Molecular assays are 500 times more sensitive in identifying cancer cells than standard techniques and provide more objective analyses with fewer sampling errors. Consequently, these techniques are currently being used to perform molecular staging of head and neck cancer patients. Preliminary results show that molecular staging will accurately identify those patients at significantly increased risk for recurrence of their head and neck cancer. 相似文献
87.
Libor Velíek† Jana Velíková Yael Ptachewich Shlomo Shinnar‡ Solomon L. Mosh醇 《Epilepsia》1995,36(2):179-185
Summary We determined the effects of the N-methyl-Daspartate (NMDA) receptor blocker MK-801 (0.05, 0.1, and 0.5 mg/kg intraperitoneally, i.p.) and phenytoin (PHT, 5, 10, and 20 mg/kg i.p.) on flurothyl-induced clonic and tonic-clonic seizures in 9-, 1 5, 30-, and 60-day-old male rats. Both agents had seizure-, age-, and dose-specific effects. The highest dose of MK-801 was anticonvulsant against clonic flurothyl-induced seizures only in 9- and 60-day-old rats, but suppressed tonic-clonic seizures in all ages. The lowest dose of MK-801 (0.05 mg/kg) produced significant anticonvulsant effects only in 15 day old rats. PHT did not have any effect on clonic seizures throughout development. Both doses of PHT (10 and 20 mg/kg) were anticonvulsant against tonic-clonic seizures in adult rats but not in any other age group. The results indicate that NMDA receptors play an important role in tonic-clonic flurothyl-induced seizures throughout development (especially in 15-day-old rats) and that the anticonvulsant effects of PHT may vary at different stages of brain development. 相似文献
88.
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90.
针对医学分子遗传学内容抽象复杂、信息更新迅速、教与学的难度都很高的问题,本研究探讨总结临床医学专业研究生课程和实习生教学中医学分子遗传学的教学方法:夯实基础理论,注重学科融合;引入临床病例,激发主动学习;突出知识更新,鼓励线上查阅;教学科研结合,启发创新思维。结果表明,学生表现出更浓厚的学习兴趣和热情,能更独立和创新地进行思考。对分子遗传学的基础理论和临床应用进行分析,问卷显示课程教学满意度为97%(152/157)。 相似文献