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191.
192.
The dynamics of dissemination of the environmental human pathogen Vibrio parahaemolyticus are uncertain. The O3:K6 clone was restricted to Asia until its detection along the Peruvian coasts and in northern Chile in 1997 in phase with the arrival of El Niño waters. A subsequent emergence of O3:K6 strains was detected in austral Chile in 2004. The origin of these 1997 and 2004 population radiations has not yet been conclusively determined. Multiple loci VNTR analysis using seven polymorphic loci was carried out with a number of representative strains from Asia, Peru and Chile to determine their genetic characteristics and population structure. Asian and Chilean subpopulations were the most genetically distant groups with an intermediate subpopulation in Peru. Population structure inferred from a minimum‐spanning tree and Bayesian analysis divided the populations into two genetically distinct groups, consistent with the epidemic dynamics of the O3:K6 clone in South America. One group comprised strains from the original Asiatic population and strains arriving in Peru and Chile in 1997. The second group included the remaining Peruvian Strains and Chilean strains obtained from Puerto Montt in 2004. The analysis of the arrival of the O3:K6 clone at the Pacific coasts of South America has provided novel insights linking the origin of the invasion in 1997 to Asian populations and describing the successful establishment of the O3:K6 populations, first in Peru and subsequently in the South of Chile owing to a possible radiation of Peruvian populations.  相似文献   
193.
叶珊慧  肖楚吟  高建全 《生物磁学》2010,(11):2103-2104
目的:对结缔组织病与其常见伴发疾病进行研究分析,探讨肿瘤等疾病与与结缔组织病的相关性。方法:收集确诊有结缔组织病患者共333例,对其临床资料并进行回顾性统计分析。结果:本文中333例结缔组织病中发生肺间质病变79例(23.7%),发生肿瘤8例(2.4%),出现肾损害有124例(37.2%)。结论:间质性肺病、肿瘤、肾损害在结缔组织病患者中占一定的比例,其机制可能与结缔组织病本身的病理生理改变、外源性因素等共同作用所致。  相似文献   
194.
The Transient Receptor Potential Vanilloid 4 channel, TRPV4, is a Ca2+ and Mg2+ permeable non-selective cation channel involved in many different cellular functions. It is activated by a variety of physical and chemical stimuli, including heat, mechano-stimuli, endogenous substances such as arachidonic acid and its cytochrome P450-derived metabolites (epoxyeicosatrienoic acids), endocannabinoids (anandamide and 2-arachidonoylglycerol), as well as synthetic α-phorbol derivatives. Recently, TRPV4 has been characterized as an important player modulating osteoclast differentiation in bone remodelling and as a urothelial mechanosensor that controls normal voiding. Several TRPV4 gain-of-function mutations are shown to cause autosomal-dominant bone dysplasias such as brachyolmia and Koszlowski disease. In this review we comprehensively describe the structural, biophysical and (patho)physiological properties of the TRPV4 channel and we summarize the current knowledge about the role of TRPV4 in the pathogenesis of several diseases.  相似文献   
195.
In addition to its role as a component of the mitochondrial respiratory chain and our only lipid-soluble antioxidant synthesized endogenously, in recent years coenzyme Q (CoQ) has been found to have an increasing number of other important functions required for normal metabolic processes. A number of genetic mutations that reduce CoQ biosynthesis are associated with serious functional disturbances that can be eliminated by dietary administration of this lipid, making CoQ deficiencies the only mitochondrial diseases which can be successfully treated at present. In connection with certain other diseases associated with excessive oxidative stress, the level of CoQ is elevated as a protective response. Aging, certain experimental conditions and several human diseases reduce this level, resulting in serious metabolic disturbances. Since dietary uptake of this lipid is limited, up-regulation of its biosynthetic pathway is of considerable clinical interest. One approach for this purpose is administration of epoxidated all-trans polyisoprenoids, which enhance both CoQ biosynthesis and levels in experimental systems.  相似文献   
196.
目的:观察噻托溴铵与布地奈德/福莫特罗联合吸入和噻托溴铵单独吸入对慢性阻塞性肺疾病(COPD)患者的疗效及安全性。方法:58例COPD患者随机分为2组:治疗组30例,给予噻托溴铵(18μg,1次/d)联合布地奈德/福莫特罗(160/4.5μg,2次/d)吸入治疗;对照组28例,给予噻托溴铵(18μg,1次/d)吸入治疗。观察患者治疗前、治疗8周和16周后肺功能及临床症状的变化。结果:治疗8周和16周后,2组FEV1和SGRQ症状评分均较治疗前明显改善(P<0.05),治疗组FEV1和SGRQ症状评分的改善显著高于对照组(P<0.05);治疗组白天使用沙丁胺醇次数更少(P<0.05)。各组均未出现明显不良反应。结论:噻托溴铵与布地奈德/福莫特罗联合吸入治疗COPD,疗效优于噻托溴铵单药治疗。  相似文献   
197.
Plasmacytoid dendritic cells (pDCs) represent a unique and crucial immune cell population capable of producing large amounts of type I interferons (IFNs) in response to viral infection. The function of pDCs as the professional type I IFN-producing cells is linked to their selective expression of Toll-like receptor 7 (TLR7) and TLR9, which sense viral nucleic acids within the endosomal compartments. Type I IFNs produced by pDCs not only directly inhibit viral replication but also play an essential role in linking the innate and adaptive immune system. The aberrant activation of pDCs by self nucleic acids through TLR signaling and the ongoing production of type I IFNs do occur in some autoimmune diseases. Therefore, pDC may serve as an attractive target for therapeutic manipulations of the immune system to treat viral infectious diseases and autoimmune diseases.  相似文献   
198.
脂质组学研究进展   总被引:4,自引:0,他引:4  
综述了脂质组学的研究现状和发展趋势.脂质组学是对生物体、组织或细胞中的脂质以及与其相互作用的分子进行系统分析的一门新兴学科.脂质具有多种重要的生物功能,脂质代谢异常可引发诸多人类疾病,包括糖尿病、肥胖症、癌症以及神经退行性疾病等.目前,脂质组学研究已成为一个前景广阔的热门领域,并广泛地应用到包括药物研发、分子生理学、分子病理学、功能基因组学、营养学以及环境与健康等重要领域.  相似文献   
199.
胚外组织尤其是胎盘的正常发生对于维持哺乳动物胎儿在子宫中的发育和生长是必须的。胎盘发生是一个复杂的基因表达调控的过程,近年来的研究表明表观遗传在该过程中也起着重要作用。表观遗传调控在胎盘发生过程的几个主要事件中发挥作用,包括表观遗传对滋养层细胞分化和发育的调控、印记基因对胎盘发生和营养转运的调控、胎盘中的X染色体失活,以及胎盘表观遗传调控异常所导致的妊娠相关疾病。  相似文献   
200.
Consider an infectious disease which is endemic in a population divided into several large sub-communities that interact. Our aim is to understand how the time to extinction is affected by the level of interaction between communities. We present two approximations of the expected time to extinction in a population consisting of a small number of large sub-communities. These approximations are described for an SIR epidemic model, with focus on diseases with short infectious period in relation to life length, such as childhood diseases. Both approximations are based on Markov jump processes. Simulations indicate that the time to extinction is increasing in the degree of interaction between communities. This behaviour can also be seen in our approximations in relevant regions of the parameter space.  相似文献   
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