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Hereditary hearing loss is one of the most common neurosensory defects in humans.Approximately 70% of cases are nonsyndromic and could be inherited in autosomal dominant,autosomal recessive,mitochondrial,X-linked,and Y-linked manners (Wang et al.,2004;Alford,2011).The autosomal dominant type,comprising 15%-20% of nonsyndromic hearing loss,is monogenic and genetically heterogeneous.Since the first dominant deafness locus (DFNA1) was identified in 1992,a total of 64 DFNA loci have been mapped (DFNA1-DFNA64),and 27 corresponding genes have been identified (http://hereditaryhearingloss.org).Previous studies have revealed that one deafness locus can be linked to more than one gene (Bayazit and Yilmaz,2006),and the question "one locus,how many genes?" was first raised about a decade ago (Van-Hauwe et al.,1999).So far,several loci,including DFNA2 and DFNA3,have been shown to be related to one or more genes,showing high genetic heterogeneity in hereditary hearing loss (Grifa et al.,1999;Goldstein and Lalwani,2002;Yan et al.,2011).  相似文献   
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Natural killer (NK) cells are abundant in the liver and have been implicated in inducing hepatocellular damage in patients with chronic hepatitis B virus (HBV) infection. However, the role of NK cells in acute HBV infection remains to be elucidated. We comprehensively characterized NK cells and investigated their roles in HBV clearance and liver pathology in 19 chronic hepatitis B (CHB) patients and 21 acute hepatitis B (AHB) patients as well as 16 healthy subjects. It was found that NKp46+ NK cells were enriched in the livers of AHB and CHB patients. We further found that peripheral NK cells from AHB patients expressed higher levels of activation receptors and lower levels of inhibitory receptors than those from CHB patients and HC subjects, thus displaying the increased cytolytic activity and interferon-γ production. NK cell activation levels were also correlated positively with serum alanine aminotransferase levels and negatively with plasma HBV DNA levels in AHB patients, which is further confirmed by the longitudinal follow-up of AHB patients. Serum pro-inflammatory cytokine and chemokine levels were also increased in AHB patients as compared with CHB and HC subjects. Thus, the concomitantly increased interferon-γ and cytotoxicity of NK cells were associated with liver injury and viral clearance in AHB patients.  相似文献   
146.
磷高效基因型小麦对缺磷胁迫的根际适应性反应   总被引:8,自引:2,他引:8  
采用奶箱分隔栽培试验法,进行了磷高效与磷低效小麦基因型根际土壤PH与有效磷变化的研究,结果表明:小麦根际土壤PH和有效磷含量皆明显低于外围土壤,表现出明显的根际效应特征;磷高效基因型小麦的根际PH和有效磷含量明显低于磷低效基因型,PH变异范围和磷素亏缺区也表现明显较大。为了进一步验证磷高效小麦基因型这的这一根际特征,同时进行了施用水溶性,枸溶性磷肥的试验研究,结果表明,以水溶性磷肥对根际PH和有效  相似文献   
147.
盐藻基因组DNA文库的构建(英文)   总被引:5,自引:0,他引:5  
以LambdaFIX○RⅡ为载体,构建了盐藻(Dunaliellasalina)的基因组文库。该文库包含了1.1×106个重组子,插入片段平均大小为18kb左右,含插入片段的频率为100%。该文库的容量约为盐藻单倍体基因组的200倍。  相似文献   
148.
The antigen‐antibody interaction determines the sensitivity and specificity of competitive immunoassay for hapten detection. In this paper, the specificity of a monoclonal antibody against alternariol‐like compounds was evaluated through indirect competitive ELISA. The results showed that the antibody had cross‐reactivity with 33 compounds with the binding affinity (expressed by IC50) ranging from 9.4 ng/mL to 12.0 μg/mL. All the 33 compounds contained a common moiety and similar substituents. To understand how this common moiety and substituents affected the recognition ability of the antibody, a three‐dimensional quantitative structure‐activity relationship (3D‐QSAR) between the antibody and the 33 alternariol‐like compounds was constructed using comparative molecular field analysis (CoMFA) and comparative molecular similarity indices analysis (CoMSIA) methods. The q2 values of the CoMFA and CoMSIA models were 0.785 and 0.782, respectively, and the r2 values were 0.911 and 0.988, respectively, indicating that the models had good predictive ability. The results of 3D‐QSAR showed that the most important factor affecting antibody recognition was the hydrogen bond mainly formed by the hydroxyl group of alternariol, followed by the hydrophobic force mainly formed by the methyl group. This study provides a reference for the design of new hapten and the mechanisms for antibody recognition.  相似文献   
149.
The interfacial electron transfer of glucose oxidase (GOx) on a poly(glutamic acid)-modified glassy carbon electrode (PGA/GCE) was investigated. The redox peaks measured for GOx and flavin adenine dinucleotide (FAD) are similar, and the anodic peak of GOx does not increase in the presence of glucose in a mediator-free solution. These indicate that the electroactivity of GOx is not the direct electron transfer (DET) between GOx and PGA/GCE and that the observed electroactivity of GOx is ascribed to free FAD that is released from GOx. However, efficient electron transfer occurred if an appropriate mediator was placed in solution, suggesting that GOx is active. The PGA/GCE-based biosensor showed wide linear response in the range of 0.5–5.5 mM with a low detection limit of 0.12 mM and high sensitivity and selectivity for measuring glucose.  相似文献   
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