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1.
研究了强平稳NA随机场对数律的收敛速度,得到了与NA随机变量序列类似的结果,推广了NA序列的情形.  相似文献   

2.
负相协(NA)随机变量是一包含独立随机变量的有广泛应用的随机变量类, 对于独立随机变量情形, Teicher给出了一类强大数律. 本文应用NA随机变量的概率不等式, 在更弱的条件下, 对具有不同分布的NA随机变量列建立了有关强大数律的定理, 进而将Teicher的结果推广到NA随机变量.  相似文献   

3.
随机变量的部分和之和在诸多领域有着广泛应用,关于NA序列的部分和之和取得了许多极限性质.在较弱的矩条件下,利用NA序列部分和之和的渐近分布和二阶矩的稳定性质,得到了平稳NA序列部分和之和的一阶矩收敛的精确渐近性,丰富了NA序列部分和之和极限理论的结果.  相似文献   

4.
本文讨论了NA r.v.序列部分和的收敛速度,将独立情形相应收敛速度的结果推广到NA随机变量.  相似文献   

5.
讨论了不同分布NA列Stout型加权和的完全收敛性和强稳定性.一些文献中对NA列加权和的完全收敛性的结论中要求函数单调,为了扩大定理的应用范围,运用讨论NA阵列加权和的完全收敛性的方法,证明了即使在函数有界的条件下NA列加权和仍是完全收敛的,使得定理得到进一步推广.  相似文献   

6.
设G是有限群,若群G的每个子群为正规子群或反正规子群,则称G为NA群.若G不是NA群,但G的每个真子群为NA群,则称G为内-NA-群.本文给出了内-NA-群的完全分类,它共有十种类型.  相似文献   

7.
首先介绍了调和NA群的基本结构和球函数的性质.其次基于调和NA群上的Helgason-Fourier变换及相应于Laplace-Beltrami算子的热核,在NA群上建立了Hardy不确定原理.所得结论推广了Thangavelu(2002年)的部分结果.  相似文献   

8.
利用随机变量的截尾方法及NA序列的三级数定理,研究了NA序列的性质,得到了矩条件下NA序列的一类强极限定理,并给出一些应用,从而推广了若干经典的强大数定理.  相似文献   

9.
该文给出了NA序列的密度核估计的均方相合性和强相合性,并对强平稳NA序列,在一定的条件下,得到了NA序列的密度核估计的中心极限定理.  相似文献   

10.
讨论了NA随机变量序列和的强收敛性,推广并改进了王月芬关于NA序列随机变量序列的一个收敛性.  相似文献   

11.
为探讨科学的鸡禽流感免疫程序,对1~28日龄的土杂肉鸡和罗曼蛋鸡进行禽流感母源抗体检测,以及对雏鸡接种禽流感油乳剂疫苗后的HI抗体水平变化进行了监测。结果表明,两种雏鸡的母源抗体水平在1日龄时均达最高值,然后逐渐下降;肉鸡11日龄后H5、H9抗体滴度分别降低到4.2log2和4.3log2以下;蛋鸡28日龄后H5、H9...  相似文献   

12.
流行性感冒(简称流感)是由流感病毒(Influenza virus,IFV)引起的一种急性呼吸道传染病,严重危害人类健康和生命.目前,临床上使用的抗流感病毒药物主要有M2离子通道抑制剂和神经氨酸酶抑制剂,接种流感疫苗仍然被认为是预防流感发生与传播的最佳方法.文章就目前流感疫苗的研究现状、研制流程、安全性和有效性的验证等多方面进行综述,为今后对疫苗进一步的研究提供了理论依据.  相似文献   

13.
禽流感是国际上公认的难以防治的鸡传染病之一,在世界各国的家禽和野禽中都有疫情出现,病毒侵入鸡群后,可出现30%~100%的死亡率,对养禽业的发展危害极大.通过对该病的流行病学调查、病毒的分离与鉴定、血清学检测,能够对该病进行准确的诊断,从而采取相应的防治措施,消灭疫情,减少损失.  相似文献   

14.
对6种禽流感病毒通用型荧光定量聚合酶链式反应(polymerase chain reaction),PCR检测试剂盒进行比对与科学评价,为实验室采购提供依据。利用禽流感病毒H5、H7、H9亚型标准品,鸡新城疫活疫苗与传染性支气管炎活疫苗对市售的6种品牌(分别记为A、B、C、D、E、F)禽流感病毒通用型荧光定量PCR检测试剂盒灵敏性与特异性进行了比对,并对97份临床样品进行了检测,筛选出禽流感病毒通用型最佳检测试剂盒。结果表明:A厂家试剂盒最低可检出1:100倍稀释的H7亚型标准品浓度,B厂家试剂盒最低可检出1:1倍稀释的H7亚型标准品浓度,C厂家试剂盒最低可检出1:10倍稀释的H7亚型标准品浓度,D厂家试剂盒最低可检出1:10倍稀释的H7亚型标准品浓度,E厂家试剂盒最低可检出1:1 000倍稀释的H7亚型标准品浓度, F厂家试剂盒最低可检出1:10倍稀释的H7亚型标准品浓度,6种试剂盒特异性均良好。综上,E厂家试剂盒优于其他厂家试剂盒,可以作为动物疫病检测实验室在实施监测任务中的首要选择。  相似文献   

15.
Influenza A (H1N1) was spread widely between cities and towns by road traffic and had a major impact on public health in China in 2009. Understanding regulation of its transmission is of great significance with urbanization ongoing and for mitigation of damage by the epidemic. We analyzed influenza A (H1N1) spatiotemporal transmission and risk factors along roads in Changsha, and combined diffusion velocity and floating population size to construct an epidemic diffusion model to simulate its transmission between cities and towns. The results showed that areas along the highways and road intersections had a higher incidence rate than other areas. Expressways and county roads played an important role in the rapid development stage and the epidemic peak, respectively, and intercity bus stations showed a high risk of disease transmission. The model simulates the intensity and center of disease outbreaks in cities and towns, and provides a more complete simulation of the disease spatiotemporal process than other models.  相似文献   

16.
Changsha was one of the most affected areas during the 2009 A (H 1N 1) influenza pandemic in China. Here, we analyze the spatial-temporal dynamics of the 2009 pan- demic across Changsha municipal districts, evaluate the relationship between case incidence and the local urban spatial structure and predict high-risk areas of influenza A (H1NI). We obtained epidemiological data on all cases of influenza A (H1NI) reported across municipal districts in Changsha dur- ing period May 2009-December 2010 and data on population density and basic geographic characteristics for 239 primary schools, 97 middle schools, 347 universities, 96 mails and markets, 674 business districts and 121 hospitals. Spatial- temporal K functions, proximity models and logistic regres- sion were used to analyze the spatial distribution pattern of influenza A (H1N1) incidence and the association between influenza A (HINI) cases and spatial risk factors and predict the infection risks. We found that the 2009 influenza A (H 1N 1 ) was driven by a transmission wave from the center of the study area to surrounding areas and reported cases increased significantly after September 2009. We also found that the distribution of influenza A (H 1N1) cases was associ- ated with population density and the presence of nearest public places, especially universities (OR = 10.166). The final pre- dictive risk map based on the multivariate logistic analysis showed high-risk areas concentrated in the center areas of the study area associated with high population density. Our find- ings support the identification of spatial risk factors and high- risk areas to guide the prioritization of preventive and miti- gation efforts against future influenza pandemics.  相似文献   

17.
The neuraminidase (NA) in viral surface is one of the main subtype-specific antigen of influenza type A viruses.Neuraminidase is an enzyme to break the bonds between hemagglutinin (HA) and sialic acid to release newly formed viruses from infected cells.In this study,the H3N2 subtype virus NA genes were sequenced and NA proteins were screened for B-cell epitopes and assessed based on immunoinformatics.Based on this results,four peptides DR6,EY7,VG8 and RE8 (covering amino acid residues 151-156,368-374,398-405 and 428-435,respectively) of the NA protein were synthesized artificially.These peptides were used to immunize New Zealand rabbits subcutaneously to raise antisera.Experimental results showed that these four peptides were capable of eliciting antibodies against H3N2 viruses in a specific and sensitive feature,detected in vitro by enzyme-linked immunosorbent assay.Moreover,hemadsorption anti-releasing effects took place in three three-antisera-mixtures at a dilution of 1:40.Alignment using NA gene database showed that amino acid residues in these four epitope peptides were substituted at specific sites in all the NAs sequenced in this study.It was suggested that these NA epitope peptides might be used in combination with HA proteins as vaccine antigens.  相似文献   

18.
禽流感是一种由A型流感病毒的一种亚型(也称禽流感病毒)引起的禽类(家禽和野禽)和人的传染性疾病,被国际兽疫局定为甲类传染病,了解和认识禽流感的流行与病毒特点、传播途径、主要症状、扑灭措施及疫苗预防,对于控制和防止禽流感的发生,以及为人类健康都有着重大意义。  相似文献   

19.
通过载体表达siRNAs抑制禽流感病毒复制的研究   总被引:3,自引:0,他引:3  
禽流感病毒是养禽业危害最严重的病原微生物之一。为探讨小干涉RNA(siRNA)对A型禽流感病毒复制的干扰作用,以H5亚型AIV PB2基因为靶序列,设计合成了4对编码siRNAs的DNA序列,将其克隆到psiRNA-hH1neo载体中,构建siRNAs表达载体,鉴定正确后将重组质粒转染MDCK细胞,采用G418筛选建立抗性细胞系,用血凝(HA)试验和real time RT-PCR试验检测抑制效果, 在细胞水平筛选出具有高效抑制AIV复制的2个靶位点PB2-1154、PB2-342、为AIV的基因功能研究,抗病毒药物的开发和转基因动物的研究奠定了基础。  相似文献   

20.
乙型流感病毒是引起人类局部流行性感冒的重要病原体,其起源和自然储存宿主目前仍不清楚。1999年夏季在某动物中心饲养的普通棉耳绒猴(Callithrix jacchus)群体中爆发了以呼吸道症状为主的急性传染病,死亡比率高达1/3。通过对死亡狨猴肺组织匀浆接种鸡胚和MDCK细胞的分离培养,分离出病毒。双份血清的红细胞凝集抑制试验证实,此分离株为此次狨猴群体感染流行的病原体。通过甲型和乙型流感病毒标准血清鉴定,证实该分离株为乙型流感病毒,命名为B/marmoset/China/1/99。  相似文献   

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