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11.
The authors have observed the rapid reorganization of the cellular membranes of macrophages during Fc receptor-mediated frustrated phagocytosis of immune complex-coated surfaces. As the macrophages spread, large, clear basal vacuoles and anastamosing tubules were formed, occasionally contiguous with the adherent surface. Coated vesicles also were observed. This process was accompanied by a rapid reorganization of the Golgi complex region of the macrophages, which was observed using trimetaphosphatase histochemistry and an antibody to a Golgi membrane antigen as markers. On contact of the macrophages with the immune complexes, the Golgi complexes, which were tightly clustered around the centrioles, dispersed into vesicles and reorganized near the basal surface. The Golgi cisternae swelled, fragmented, and decreased in number. Golgi membrane antigen was found in the large basal vacuoles and also associated with the adherent basal surface of the macrophages. This indicates that the Golgi complexes were reorganized, in part, by a direct recruitment of their membranes to the increasing basal surface area of the spreading macrophages. The changes in the structure of the Golgi complexes were reversible; by 2 hours, the complexes had recovered their normal organization, with an accompanying decrease in the number of large basal vacuoles. These data suggest that the dynamic interrelationship among the Golgi membranes, intracellular vacuoles, and the plasma membrane can be perturbed by membrane spreading on a nonphagocytosable surface.  相似文献   
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藏汉民族线粒体基因组全序列的比较研究   总被引:1,自引:0,他引:1  
目的 以藏汉民族线粒体基因组全序列为基础,进行Haplogroup构建和系统发生分析,在全序列水平上比较核苷酸的变异,阐释可能的变异机制和蕴含的生物学意义.方法 采用Applied Biosystems 3730DNA自动测序仪分别对40名藏族和50名汉族的标本进行线粒体DNA序列测定,应用phredPhrap 16.0软件进行全序列拼接,并以rCRS(revised Cambridge Reference Sequence)为标准与测定序列进行比对分析;根据MTTO-MAP的标准,通过Network方法进行Haplogroup构建和系统发生的分析,并结合其它方法对产生的数据进行深入解读.结果 数据分析结果显示:在系统发生上,藏汉民族90个线粒体DNA序列归类到13个Haplogroups,除M9以外,其它各Haplogroup出现频率之间比较差异无统计学意义;通过两个民族的线粒体DNA全序列比对,发现21个分布频率有统计学意义的变异位点,其中的5个为新变异位点;另外,对D-Loop区的5个突变位点进行了单倍型构建,90个标本可分为2种Supertype,发现在藏汉民族之间Supertypel和Supertype 2的分布频率均有统计学意义.结论 藏汉民族在种族起源和系统发生上具有较近的母系遗传关系;在全序列有统计学意义的位点究竟是适应性或者中性选择,抑或是一种病理性突变尚需深入的探讨.  相似文献   
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Journal of Community Health - The purpose of this study was to evaluate family physicians’ job strain during the Covid-19 pandemic and determine the effective factors. The study was carried...  相似文献   
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松质骨中两种纵波的传播特性分析   总被引:2,自引:1,他引:2  
基于松质骨的层状模型,利用Schoenberg理论分析了松质骨中两种纵波(快纵波和慢纵波)的传播特性;并在理论和实验上详细分析了骨小梁方向与传播方向间的夹角对松质骨中快纵波和慢纵波传播特性的影响。分析结果表明,当超声波平行于骨小梁入射时,松质骨中两种纵波都传播,入射角度在60度附近时,松质骨中两种纵波的相速度曲线有一个转折点,入射角度在60度以上,角度越大时,骨髓和骨小梁耦合得越紧,因此阻止了慢纵波的传播,而只有快纵波传播。  相似文献   
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A biodegradable polylactic acid membrane was evaluated for its ability to enhance periodontal regeneration. In 8 Labrador dogs, circumferential defects were created around the maxillary 1st premolars. The defects were combination "1-wall vertical and horizontal". A membrane was adjusted to cover the defect on one side of the jaw, while the contralateral tooth served as control without membrane. After 3 months, healing was evaluated histologically. The results demonstrated that the amount of connective tissue repair with newly formed cementum approximated 50% of the defect height for both test and control groups. Thus, no advantage to the use of membrane was found, which is contradictory to the findings of our previous dog study using the same biodegradable membrane. The possible reasons for this difference in results are discussed relative to suggested mechanisms for membrane effects in periodontal regeneration.  相似文献   
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Transglutaminases (transamidases; endo--gluta-mine: -lysine transferases) are calcium-dependent enzymes, which cross-link proteins by introducing covalent -(-gluta-minyl)lysine pseudopeptide bonds between the molecules. The distribution and characteristics of transglutaminase in both human and rabbit eyes have been studied. Transglutaminase activity was measured with an isotope technique based on the enzyme catalysed incorporation of14C-putrescine into casein. Electrophoretic characteristics were studied using agarose gel electrophoresis combined with a specific fluorescent activity staining procedure based on the transglutaminase catalysed incorporation of monodansylthiacadaverine into casein.A thrombin-independent enzyme, indistinguishable from the guinea pig liver transglutaminase with regard to electrophoretic mobility, was found in the choroid/pigment epithelium and ciliary body of the human eye while the lens, retina, iris and vitreous humour did not contain detectable amounts. The lens and the choroid/pigment epithelium of the rabbit eye tissues contained high activities while the activity in the extract from the combined ciliary body/iris was low but measurable.  相似文献   
19.
小牛血去蛋白提取物对胃溃疡患者的疗效评价   总被引:2,自引:0,他引:2  
目的:探讨小牛血去蛋白提取物(DCBE)对胃溃疡的治疗作用。方法:选择年龄20~70岁之间,经胃镜检查确诊为活动期胃溃疡的住院患60例。治疗组32例采用静脉滴注DCBE(800mg,qd)和法莫替丁(100mg,bid)治疗;对照组28例采用静脉滴注法莫替丁(100mg,bid)单独治疗。用药2、4wk行胃镜检查,观察自觉缓解症状、时间、愈合率和总有效率。结果:治疗组自觉症状缓解时间明显缩短;给药后2、4wk治疗组及对照组胃镜检查溃疡愈合率分别为78.1%,46.4%及84.4%,71.4%。结论:DCBE能显促进胃溃疡的愈合。  相似文献   
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ObjectivesTo provide overview of research on training interventions for healthcare providers aimed at promoting competencies in delivering group-based patient education.MethodsA systematic literature search identified relevant studies. Data was extracted on training details, study design, outcomes and experiences. Results were summarized and qualitative data analyzed using content analysis.ResultsTwenty-seven studies exploring various training interventions were included. Ten studies used qualitative methods, eight quantitative and nine mixed methods. Use of a comparison group, validated instruments and follow-up measures was rare. Healthcare providers’ reactions to training were mostly positive. Several studies indicated positive short-term effects on self-efficacy and knowledge. Results on observed skills and patient outcomes were inconclusive. Results on healthcare providers’ experience of delivery of group-based patient education following training were categorized into 1) Benefits of training interventions, 2) Barriers to implementation and 3) Delivery support.ConclusionsFurther evaluation of training for healthcare providers delivering group-based patient education is needed before conclusions on training efficacy can be drawn. The results indicate an expanding research field still in maturation.Practice implicationsEfficacy studies evaluating theoretically grounded training with clear attention on group facilitation and follow-up support are needed. Inclusion of validated instruments and long-term outcomes is encouraged.  相似文献   
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