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1.

Background

The transmission of hemorrhagic fever with renal syndrome (HFRS) is influenced by population dynamics of its main host, rodents. It is therefore important to better understand rodents’ characteristic in epidemic areas.

Methodology/Principal Findings

We examined the potential impact of food available and climatic variability on HFRS rodent host and developed forecasting models. Monthly rodent density of HFRS host and climate data in Changsha from January 2004 to December 2011 were obtained. Monthly normalized difference vegetation index (NDVI) and temperature vegetation dryness index (TVDI) for rice paddies were extracted from MODIS data. Cross-correlation analysis were carried out to explore correlation between climatic variables and food available with monthly rodent data. We used auto-regressive integrated moving average model with explanatory variables to examine the independent contribution of climatic variables and food supply to rodent density. The results indicated that relative rodent density of HFRS host was significantly correlated with monthly mean temperatures, monthly accumulative precipitation, TVDI and NDVI with lags of 1–6 months.

Conclusions/Significance

Food available plays a significant role in population fluctuations of HFRS host in Changsha. The model developed in this study has implications for HFRS control and prevention.  相似文献   
2.
Hydroxyapatite (HAp) is the major inorganic component in natural bones. Because HAp has the advantages of excellent biocompatibility, free of cell toxicity, and forming strong bonding to bone osteoinductively, it has been widely studied and prepared in many forms for orthopedic and dental applications. In the recent years, silicon based bio-chip was extensively studied. To improve the biocompatibility and search for novel application of bio-chip are not only an important aim but also a challenge. In the previous literatures, it's reported that HAp is relatively difficult to be coated onto a Si(1 0 0) substrate. In this study, we successfully manufactured crystalline HAp on to Si(1 0 0) using simplified supersaturated solution and investigated the structural characteristics through the measurements of XRD, FTIR, FE-SEM, and XPS. The photo-luminescent properties of the coatings were also studied.  相似文献   
3.
Based on the two antigenic peptides, 26-43 (P26) and 116-131 (P116), derived from 28 kDa glutathione S-transferase of Schistosoma mansoni (Sm28GST), two multiple antigenic peptides (MAPs), (P26)4-MAP and (P116)4-MAP with the same oligomeric lysine core, were synthesized by stepwise solid-phase peptide synthesis method. The antigenicities and protective effects of these two MAPs were examined on experimental animals. As shown in the dot-ELISA result, the synthetic MAPs could be recognized and bound by immunoglobins in both patient's and infected-rabbit's sera. After Kunming mice were immunized with (P26)4-MAP, the worm burden reduction rate and the liver egg reduction rate were 59.9% and 61.1%. In (P26)4-MAP or (P116)4-MAP immunized BALB/c mice, the worm burden reduction rates were 37.5% and 62.5%, respectively, and the liver egg reduction rates were 35.1% and 54.0%, respectively.  相似文献   
4.
A feature of the rat brain gamma-aminobutyric acid transporter GAT1, and other members of the neurotransmitter transporter family, is its regulated redistribution between intracellular locations and the plasma membrane. Recent studies have focused upon defining the signaling molecules that facilitate this redistribution. Agents that promote direct tyrosine phosphorylation of GAT1 promote a relative increase in surface GAT1 levels, and this results from a slowing of the transporter internalization rate. Agents that act to increase protein kinase C (PKC) activity promote a relative decrease in surface GAT1 levels; whether this effect is caused by direct transporter phosphorylation is unknown. The opposing actions of tyrosine kinase activity and PKC activity raise the possibility that the subcellular distribution of GAT1 is associated with mutually exclusive transporter phosphorylation events. The present experiments show that GAT1 is phosphorylated on serine residues in a PKC-dependent manner, but this state is only revealed when GAT1 tyrosine phosphorylation is eliminated or greatly reduced. The relative levels of serine phosphorylation and tyrosine phosphorylation are negatively correlated. The amount of serine phosphorylation is regulated by agents that affect tyrosine phosphorylation, and vice versa. In addition, the ability of agents that affect tyrosine kinase activity to regulate GAT1 serine phosphorylation requires a change in its tyrosine phosphorylation state. These data support the ideas that GAT1 can exist in either of two mutually exclusive phosphorylation states and that the relative abundance of these states determines in part the relative subcellular distribution of the transporter.  相似文献   
5.
兔肺静脉肌袖心肌细胞动作电位的特性和一些离子流机制   总被引:3,自引:0,他引:3  
Ding HY  Yang XC  Liu XL  Liu TF  Bao RF 《生理学报》2006,58(2):129-135
研究兔肺静脉肌袖心肌细胞(cardiomyocytes from rabbit pulmonary vein sleeves, PVC)动作电位的特性和一些离子流机制——内向整流钾电流(IKl)、瞬时外向钾电流(ITo)和非选择性阳离子流(I NSCC),并与左心房心肌细胞(left atrial cardiomyocytes,LAC)进行比较。采用全细胞膜片钳技术,记录动作电位和上述各离子流。发现PVC动作电位时程(action potential duration,APD)较LAC的明显延长,并可以诱发出第二平台反应。PVC上存在I NSCC. PVC的IKl、I To和I NSCC电流密度均较LAC的明显减小。PVC和LAC存在复极离子流的差异,这种差异构成了两者动作电位差异的基础,进而可能成为肺静脉肌袖致心律失常特性的重要离子流机制。  相似文献   
6.
Apidermin (APD)蛋白家族是一个新的昆虫结构性表皮蛋白家族。本研究结合生物信息学和RT-PCR扩增, 对意大利蜜蜂Apis mellifera ligustica(简称“意蜂”)的apd-1-like, apd-3-like和中华蜜蜂Apis cerena cerena(简称“中蜂”)的apd-2 等3个新的apd基因的结构特征和表达进行了分析, 并分析了昆虫APD蛋白家族的序列特征。结果显示, 在西方蜜蜂Apis mellifera(简称“西蜂”)中, apd基因家族的6个成员串联排列在基因组序列第4号连锁群上, 它们在A. m. ligustica雄蜂头部中的转录水平差异明显, 且其启动子序列所含顺式元件也不同。中蜂apd-2和意蜂apd-1-like都含有3个外显子和2个内含子, 而意蜂apd-3-like则由4个外显子和3个内含子组成。蛋白序列分析结果显示, 目前已知的10条APD蛋白序列N末端均具有相似的信号肽序列, 其成熟蛋白分子量为6.0~37.0 kD, pI为6.2~10.8。其中西蜂的APD1-3、APD-like和东方蜜蜂Apis cerena的APD-2等5条较短的多肽中疏水氨基酸残基达52%~67%, 且Ala含量最为丰富(占25%~34%); 而丽蝇蛹集金小蜂Nasonia vitripennis的APD 1-3和西蜂APD-1-like, APD-3-like等另外5条APD多肽富含Gly(21%~30%), 其序列中疏水氨基酸残基含量为35%~41%。多肽序列多重比对和系统进化分析结果显示, APD家族可划分为2个亚家族。亚家族Ⅰ含有西蜂APD 1-3和东方蜜蜂APD-2等4条较短的多肽序列, 其N末端为一个长33 aa的保守基序; 亚家族Ⅱ由另外6条相对较长的多肽序列组成, 其N末端保守基序长50 aa, C末端保守基序长16 aa。本文所描述的APD蛋白家族序列特征有助于以后从其他昆虫中鉴定新的apd基因。  相似文献   
7.
高粱丝黑穗病菌种内分化的RAPD分析   总被引:4,自引:0,他引:4  
应用随机引物对来自不同地理来源、不同寄主和经寄主致病力测定的高粱丝黑穗病菌2、3号生理小种的10个菌株的DNA进行分析,所产生的RAPD结果表明,丝黑穗病菌S.reilianum具有丰富的种内遗传多样性,存在明显的分化现象。经聚类分析可将供试菌株大致分成两组,辽宁清原H2和黑龙江绥化H9菌株为一组。辽宁沈阳(H3)、阜新(H1)、营口(H10),山西榆次(H4),吉林四平(H5),黑龙江哈尔滨(H6),河北张家口(H8)等高粱丝黑穗病菌株以及辽宁沈阳的玉米丝黑穗病菌株(H7)为另一组,并且同一组内的DNA多态性亦有差异。高粱丝黑穗病菌2号生理小种和3号小种间在分子水平上存在差异明显。  相似文献   
8.
外源H2O2对湖北海棠根系线粒体膜透性和细胞核DNA的影响   总被引:4,自引:0,他引:4  
用0.024%(V/V)H2O2处理湖北海棠(Malus hupehensis Rehd.)实生苗根系,30min后,根系线粒体膜通透,陛明显增大,线粒体膜电位(△ψm)和线粒体内Cyt c/a吸光度比值下降;60min后,根系细胞核DNA发生片段化降解。经荧光染料吖啶橙染色后,可见H2O2处理60min以上的根系压片中出现了清晰致密的黄绿色荧光宽,呈现出细胞程序,陛死亡(PCD)的特征。  相似文献   
9.
目的:研究大鼠骨髓间质干细胞(MSCs)移植治疗脑出血的可行性。方法:分离MSCs后,连续传代培养、扩增,Brdu标记的MSCs通过颈动脉、侧脑室2种途径移植入脑出血大鼠模型体内,采用爬行计分法评估神经功能的恢复程度,并观察脑部Brdu阳性细胞的分布。结果:通过侧脑室、颈动脉移植后大鼠神经功能改善,明显优于对照组(P<0.05);经颈动脉注射组较经侧脑室注射组爬杆实验评分低(P<0.05)。移植的MSCs主要迁移到出血灶、大脑皮层、海马区等处。结论:MSCs移植对脑出血具有保护作用,而经颈动脉给药疗效优于经侧脑室给药。  相似文献   
10.
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