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This study investigated the nuclear organization of four immunohistochemically identifiable neural systems (cholinergic, catecholaminergic, serotonergic and orexinergic) within the brains of three male Tasmanian devils (Sarcophilus harrisii), which had a mean brain mass of 11.6 g. We found that the nuclei generally observed for these systems in other mammalian brains were present in the brain of the Tasmanian devil. Despite this, specific differences in the nuclear organization of the cholinergic, catecholaminergic and serotonergic systems appear to carry a phylogenetic signal. In the cholinergic system, only the dorsal hypothalamic cholinergic nucleus could be observed, while an extra dorsal subdivision of the laterodorsal tegmental nucleus and cholinergic neurons within the gelatinous layer of the caudal spinal trigeminal nucleus were observed. Within the catecholaminergic system the A4 nucleus of the locus coeruleus complex was absent, as was the caudal ventrolateral serotonergic group of the serotonergic system. The organization of the orexinergic system was similar to that seen in many mammals previously studied. Overall, while showing strong similarities to the organization of these systems in other mammals, the specific differences observed in the Tasmanian devil reveal either order specific, or class specific, features of these systems. Further studies will reveal the extent of change in the nuclear organization of these systems in marsupials and how these potential changes may affect functionality. 相似文献
83.
王文文 《国际生殖健康/计划生育杂志》2012,31(4):312-315
卵巢癌是妇科常见恶性肿瘤之一,病死率居妇科肿瘤之首.因早期多无明显症状体征且缺乏敏感和特异的筛选手段,70%以上的患者发现时已为晚期,多伴有腹水、盆腹腔广泛转移,恶性程度高,预后极差,故卵巢癌的早发现早诊断在提高生存率方面显得尤为重要.近年表观遗传学的研究进展迅速,在卵巢癌发生发展治疗等方面具有重要的指导意义,为卵巢癌的早期诊断、优化治疗、改善预后指明新方向.DNA甲基化是最常见也是目前研究最清楚的表观遗传修饰形式,能引起染色质结构、DNA构象、DNA稳定性及DNA与蛋白质相互作用方式的改变,调控基因表达,在肿瘤的发生发展中扮演重要角色.就DNA甲基化在卵巢癌表观遗传学中的研究进展作一综述. 相似文献
84.
Please cite this paper as: Shanks et al. (2012) Epidemiological isolation causing variable mortality in Island populations during the 1918–1920 influenza pandemic. Influenza and Other Respiratory Viruses 6(6), 417–423. Background During the 1918 pandemic period, influenza‐related mortality increased worldwide; however, mortality rates varied widely across locations and demographic subgroups. Islands are isolated epidemiological situations that may elucidate why influenza pandemic mortality rates were so variable in apparently similar populations. Objectives Our objectives were to determine and compare the patterns of pandemic influenza mortality on islands. Methods We reviewed historical records of mortality associated with the 1918–1920 influenza pandemic in various military and civilian groups on islands. Results and Conclusions Mortality differed more than 50‐fold during pandemic‐related epidemics on Pacific islands [range: 0·4% (Hawaii) to 22% (Samoa)], and on some islands, mortality sharply varied among demographic subgroups of island residents such as Saipan: Chamorros [12%] and Caroline Islanders [0·4%]. Among soldiers from island populations who had completed initial military training, influenza‐related mortality rates were generally low, for example, Puerto Rico (0·7%) and French Polynesia (0·13%). The findings suggest that among island residents, those who had been exposed to multiple, antigenically diverse respiratory pathogens prior to infection with the 1918 pandemic strain (e.g., less isolated) experienced lower mortality. The continuous circulation of antigenically diverse influenza viruses and other respiratory infectious agents makes widespread high mortality during future influenza pandemics unlikely. 相似文献
85.
Achieving irreducibility of the Markov chain Monte Carlo method applied to pedigree data 总被引:3,自引:0,他引:3
Markov chain Monte Carlo (MCMC) methods have been explored byvarious researchers as an alternative to exact probability computationin statistical genetics. The objective is to simulate a Markovchain with the desired equilibrium distribution. If the transitionkernel is aperiodic and irreducible, then convergence to theequilibrium distribution is guaranteed; realizations of theMarkov chain can thus be used to estimate desired probabilities.Aperiodicity is easily satisfied, but, although it has beenshown that irreducibility is satisfied for a diallelic locus,reducibility is a potential problem for a multiallelic locus.This is a particularly serious problem in linkage analysis,because multiallelic markers are much more informative thandiallelic markers and thus highly preferred. In this paper,the authors propose a new algorithm to achieve irreducibilityof the Markov chain of interest by introducing an irreducibleauxiliary chain. The irreducibility of the auxiliary chain isobtained by assigning positive probabilities to a small subsetof the genotypic configurations inconsistent with the data,to bridge the gap between the irreducible sets. 相似文献
86.
目的 对胰岛移植在维持受体内糖代谢稳定方面的能力进行评价。方法 应用静脉糖耐量试验。结果 胰岛移植物在受体内对葡萄糖刺激具有良好的反应,其胰岛素的分泌接近于正常胰腺糖负荷后胰岛素的生理分泌模式,胰岛移植可以有效地维持受体内糖代谢的稳定。结论 胰岛移植是治疗1型糖尿病的理想方法。 相似文献
87.
试论登岛作战卫勤保障需求与卫生装备研究 总被引:2,自引:0,他引:2
本文探讨了登岛作战卫勤保障需求和卫生装备研究的有关问题,研究提出了:登岛作战卫勤保障将呈现需求多元化、阶梯扁平化和聚焦卫勤能力等新特点;不同作战阶段、不同作战样式引发不同的伤员救治需求,航渡、抢滩登岛和扩大登陆场作战伤员救治需求是重中之重;应优先研制海上、岛上及“三防”作战卫勤保障专用卫生装备,完善配套单兵自救互救及师救护所医技保障装备,解决岛上伤员战略、战役后送和卫生装备战略投送问题,形成5种卫勤保障能力,即:海上系列救治装备保障能力、生防系列救治装备保障能力、单兵非医救治自我保障能力、师救护所医技自我保障能力和卫生装备信息化保障能力;加强登岛作战的卫勤理论研究,加强卫生装备科研的组织领导工作,顶层设计、整合力量、集中财力,采用新的组织体制和运行机制,形成科技攻关合力、科技攻关助推力和科技攻关制度约束力。 相似文献
88.
Angelika Böger Waldemar Hort 《Virchows Archiv : an international journal of pathology》1977,372(4):287-297
Summary Foam cells in lipid islands of the stomach can develop from both histiocytes and smooth muscle cells. With increasing storage of lipid vacuoles in smooth muscle cells, loosening of the myofilament arrangement and decrease of the dense areas subjacent to the plasma membrane occurs. Endoplasmic reticulum and the cisternae of the Golgi-apparatus dilate, the cell organelles increase initially and the basement membrane of the smooth muscle cells is fragmentarily formed. Only in incompletely formed foam cells can the origin from smooth muscle cells be recognised, in their final state their histiogenesis is seldom apparent.The authors are grateful to H. Gerdes for leaving the specimens and to R. Naumann and H. Staubitz for technical and photographic assistance. 相似文献
89.
目的研究成釉细胞瘤(ameloblastoma,AB)中hTERT启动子区的DNA甲基化,并探讨其生物学意义。方法选取新鲜标本AB12例,同时用11例正常黏膜做对照观察,用甲基化特异PCR检测上述组织中人类端粒酶反转录酶(human telomerase reverse transcripase,hTERT)启动子区的DNA甲基化。结果AB、正常黏膜中hTERT启动子区的DNA非甲基化阳性分别为4例(4/12)和6例(6/11)。AB、正常黏膜中hTERT启动子区的DNA甲基化阳性分别为11例(11/12)和3例(3/11),其中4例AB和1例正常黏膜同时表现hTERT启动子区DNA的甲基化和非甲基化。结论AB的hTERT启动子区的DNA甲基化比正常黏膜常见且有意义;hTERT启动子的甲基化可能对hTERT基因起调节作用。 相似文献
90.