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11.
新的质粒介导的碳青霉烯酶IMI-3传播机制研究 总被引:3,自引:0,他引:3
目的明确新的质粒介导的碳青霉烯酶IMI-3传播机制.方法采用E试验测定抗菌药物MIC,接合试验、酶切克隆筛选及鸟枪法测序对编码基因IMI-3传播机制进行研究.结果发现阳性克隆菌E.coli pT103有5个开放读码框(ORF).在编码基因IMI-3的两侧各有一相同的插入序列,氨基酸序列与IS903有71%的同源性.鸟枪法测序显示IMI-3与染色体介导的IMI-有99%的同源性.结论IMI-3编码基因是由位于染色体上的IMI-1经点突变通过转座酶Tn903转移至可接合性质粒上. 相似文献
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13.
脂肪组织除了通过其力学特征或机械功能对周边组织器官产生影响以外,还可以凭借非物理性的内分泌功能通过脂肪因子输出信号方式有效地建立起与呼吸系统等远程器官的互作信息网络,进而参与多种肥胖相关疾病的发生与发展。作为内分泌领域的突破性进展之一,脂肪组织的内分泌功能受到生命科学领域的关注。近年来,多项流行病调查研究揭示了肥胖是造成慢性阻塞性肺疾病(COPD)等呼吸系统疾病肺功能损害重要的危险因素。基于此,本文将分别梳理脂联素、瘦素、内脂素等脂肪因子在COPD中的作用机制,从脂肪组织内分泌功能角度为COPD的防治研究提供新思路。 相似文献
14.
He X Wolkers WF Crowe JH Swanlund DJ Bischof JC 《Annals of biomedical engineering》2004,32(10):1384-1398
The in situ thermal protein denaturation and its correlation with direct hyperthermic cell injury in Dunning AT-1 prostate tumor cells were investigated in this study. The in situ thermal protein denaturation was studied using both Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The FTIR spectra at different temperatures show changes in protein secondary structure (from alpha helix to extended beta sheet) during in situ thermal protein denaturation within AT-1 cells. Calorimetric studies using DSC show that endothermic heat release is associated with the in situ thermal protein denaturation. Furthermore, both the secondary structure changes detected by FTIR and the calorimetric changes detected by DSC were quantified and the kinetics of the overall in situ thermal protein denaturation was derived under different heating conditions. The onset temperature where the overall in situ thermal protein denaturation is first detectable was found to be scanning rate dependent (approximately 41 degrees C at 2 degrees C min(-1) and approximately 44 degrees C at 5 degrees C min(-1)). The kinetics of the overall in situ thermal protein denaturation was derived from both DSC and FTIR measurements and was fit using kinetic and statistical models. The kinetic data determined by FTIR and DSC under the same heating conditions match well with each other. The activation energy of the overall in situ thermal protein denaturation is found to be strongly dependent on the temperature range considered (the activation energy ranges from approximately 110 kJ mol(-1) between 44 and 90 degrees C to approximately 750 kJ mol(-1) between 44 and 50 degrees C). However, its dependence on heating rate is negligible. Several denaturation peaks, including a dominant one between approximately 62 and 65 degrees C, are identifiable from both the DSC and the FTIR results. To investigate directly the relationship between thermally induced cell injury and the in situ thermal protein denaturation, both acute (propidium iodide dye exclusion, assessed 3-h postthermal treatment) and chronic (clonogenics, assessed 7-day postthermal treatment) cell injury were quantified using AT-1 cells prepared under the same conditions as for the DSC protein studies. Comparisons of the results from the cell injury studies and the DSC protein denaturation studies show that the overall in situ thermal protein denaturation correlates well with both the acute and the chronic cell injury, which suggests that overall in situ thermal protein denaturation is an important mechanism of direct hyperthermic cell injury in AT-1 cells at the macromolecular level. 相似文献
15.
研究了电化学治疗昆明小鼠肉瘤的疗效,并分析其机理。在体外将S-180细胞用不同参数的电场处理,研究适合电化学治疗的电场条件。通过复制肉瘤模型,将肉瘤小鼠随机分成4组:对照组、电疗组、化疗组、电化疗组。研究了不同处理组的肿瘤抑瘤率、治愈率以及小鼠的自由基代谢水平。结果电化疗组的抑瘤率、治愈率都显著高于化疗组和电疗组(P<0.05),电化疗组小鼠受到氧自由基的攻击显著降低,免疫力提高。分析机理发现,电化学治疗肿瘤的机理可能至少涉及细胞膜通透性提高、细胞的耐药性降低、机体的免疫力提高三个方面。 相似文献
16.
Transcranial magnetic stimulation 总被引:2,自引:0,他引:2
Bächtold D Baumann T Sándor PS Kritos M Regard M Brugger P 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2001,136(1):128-132
We investigated the effects of unilateral cold-water vestibular stimulation on healthy subjects' performance in two cognitive tasks known to be differentially mediated by the two cerebral hemispheres. In a first experiment (right-hemisphere task), subjects memorized object-location associations while being stimulated with cold water in the left ear or right ear or not at all (control group). In the second experiment (left-hemisphere task), subjects memorized a list of sequentially presented function words while being stimulated in the same manner as the subjects in the first experiment. A recall phase followed each encoding phase. In the first experiment, subjects who had been stimulated in the left ear recalled the object locations significantly faster than subjects who had been stimulated in the right ear and those in the control group. The second experiment yielded the reverse pattern: correct word recognition was faster for subjects who had been stimulated in the right ear than for subjects stimulated in the left ear and those of the control group. We suggest that unilateral caloric stimulation leads to a selective activation of contralateral cerebral structures and speeds up cognitive processes mediated by these structures. These results are discussed with respect to findings in neglect patients and functional-imaging studies in healthy subjects. 相似文献
17.
Pirzada OL 《Bulletin of experimental biology and medicine》2002,133(6):574-576
In vivo experiments on rats and rabbits showed that megestrol caproate, a 17-alpha-hydroxyprogesterone derivative exhibits 10-fold higher gestagenic activity compared to progesterone and possesses no androgenic, anabolic, and estrogenic activities. 相似文献
18.
陶立波王芳旭陈斌斌 《中国卫生质量管理》2021,(5):016-18
近年来,我国医用耗材管理机制改革不断深入。基于对我国医用耗材管理现况和新医保政策动向的分析,探讨了既往管理模式的弊端和医保部门在耗材目录、定价、采购、支付、监管等方面的政策进展。建议医疗机构和医务人员要正视耗材改革的推进,积极优化临床诊疗工作流程,追求医疗质量和成本控制之间的平衡,以适应新的政策环境,促进我国医疗卫生事业健康发展。 相似文献
19.
郭逸李恒新郭康社张雅莉曹晓莉刘清肖利涛景媛媛 《中国卫生质量管理》2021,(12):080-82
建立血液调配机制,可缓解医疗资源相对丰富的中心城市临床血液供需矛盾,逐渐实现采供血服务均衡化。建立了陕西省血液调配机制,实现了省域中心城市与周边城市血液资源的均衡化。认为不断优化血液调配机制,加强中心城市与周边城市采供血机构间的沟通合作,是实现省域内血液资源均衡、缓解中心城市季节性供血紧张的有效方法之一。 相似文献
20.
幽门螺杆菌感染与缺血性心脑病的关系探讨 总被引:2,自引:0,他引:2
目的:探讨幽门螺杆菌(HP)感染与缺血性心脏病(IHD)的关系以及可能的发病机理。方法:应用酶联免疫法测定IHD组(142例)和对照组(50例)血清特异性HP抗体(HPIgG),用全自动生化仪测定血清TC,TG<ApoA1,ApoB,Lp(a),HDL-c,LDL-c含量,应用全自动凝血仪测定血中纤维蛋白原浓度(Fbg),化学比色法测定血清中NO和NOS含量。结果:IHD组血清HPIgG阳性率明显高于对照组(65.49%VS28.00%,P<0.0001),经多元回归分析显示HP感染与IHD发病呈明显的正相关(P=0.0004),HPIgG阳性者的TG,ApoB,NO,NOS含量明显增高(P<0.05),TC,Lp(a),LDL-c,Fbg含量有增高趋势。结论:HP感染与IHD的发生有明显的相关性,其可能的发病机理为HP感染改变了脂质代谢和血管的内皮功能来增加发生IHD的危险。 相似文献