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61.
Riemerella anatipestifer is the causative agent of septicemia anserum exsudativa in ducks. Its pathogenesis and virulence factors are still unclear. The glycolytic enzyme, glyceraldehyde-3-phosphate dehydrogenase (GAPDH), an anchorless and multifunctional protein on the surface of several pathogenic microorganisms, is involved in virulence and adhesion. Whether homologs of GAPDH exist, and display similar characteristics in R. anatipestifer (RaGAPDH) has not been determined. In our research, the RaGAPDH activity from various R. anatipestifer isolates was confirmed. Twenty-two gapdh genes from genomic DNA of R. anatipestifer isolates were cloned and sequenced for phylogenetic analysis. The distribution of RaGAPDH in R. anatipestifer CZ2 strain was confirmed by antisera to recombinant RaGAPDH. The ability of purified RaGAPDH to bind host proteins was analyzed by solid-phase ligand-binding assay. Results revealed that all R. anatipestifer isolates showed different levels of GAPDH activity except four strains, which contained a gapdh-like gene. The gapdh of R. anatipestifer, which is located phylogenetically in the same branch as enterohemorrhagic Escherichia coli (EHEC), belonged to class I GAPDH, and encoded a 36.7-kDa protein. All RaGAPDH-encoding gene sequences from field isolates of R. anatipestifer displayed 100% homology. The RaGAPDH localized on the extracellular membrane of several R. anatipestifer strains. Further, it was released into the culture medium, and exhibited GAPDH enzyme activity. We also confirmed the binding of RaGAPDH to plasminogen and fibrinogen. These results demonstrated that GAPDH was present in R. anatipestifer, although not in all strains, and that RaGAPDH might contribute to the microorganism’s virulence.  相似文献   
62.
通过PCR和DNA测序技术,获得了大鳞副泥鳅(Paramisgurnus dabryanus)线粒体基因组的部分序列,所得4段序列长度共计11552 bp,包括5个蛋白质编码基因(ND1、ND2、ND4、ND4L、ND6和Cytb),14个t RNA基因.本研究获得序列的碱基组成为A 28.9%、C 27.7%、G 15.7%、T 27.7%,可看出(A+T)(C+G);测出的蛋白编码基因的碱基都有一个明显的现象,就是G的含量很明显的少于其他碱基,而C的含量都比较高,并且(A+T)(C+G),这样的结果表现出明显的反G偏倚和碱基组成偏好性.将大鳞副泥鳅Cytb序列与Gen Bank其他6种鱼类的Cytb序列进行%对,表明大鳞副泥鳅与洛东江高丽鳅和俄罗斯泥鳅亲缘关系最近.用NJ法构建7种鱼类的进化关系树,结果表明:大鳞副泥鳅与洛东江高丽鳅和俄罗斯泥鳅最先聚类,再与其他鳅科鱼类相聚,最后与鲤科鱼类斑马鱼相聚,结果与传统分类一致.  相似文献   
63.
Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.  相似文献   
64.
The presentation of long-chain fatty acid oxidation disorders (FAOD), unlike short and medium-chain disorders can be with secondary defects in mitochondrial function along with typical features of FAOD. We report an infant with Reye-like presentation and acylcarnitine profile suggestive of very-long-chain acyl-CoA dehydrogenase deficiency who had lactic acidosis and urine gas chromatographic pattern of mitochondrial defects.  相似文献   
65.
It is shown that the maximum likelihood estimator of the widely used omega coefficient for reliability of multicomponent measuring instruments converges almost surely to the population reliability coefficient for normal congeneric measures with uncorrelated errors as sample size increases indefinitely. This strong consistency implies convergence in probability (consistency) as well as in distribution for the omega estimator. Strong consistency is also demonstrated for the maximal reliability estimator associated with the optimal linear combination of the instrument components. The findings of this note add (i) to the recommendation to use in the general normality case the omega estimator in empirical research, (ii) to the critical literature on the popular coefficient alpha then, and (iii) to the literature on the properties of the optimal linear combination of observed measures and the maximal reliability estimator.  相似文献   
66.
将均三嗪型活性染料—活性嫩黄M—7G共价偶于聚乙二醇(PEG6000)分子上,构建双水相系统,能使醇母脱氢酶(以下简称ADH)分配系数增值11倍。观察了影响ADH分配系数的各种因素,设计了借液—液萃取方式快速部分纯化ADN的方案,经部分纯化后,ADH的比活力按每毫克制剂含单位数计算提高至700倍;按每毫克蛋白质含单位数计算提高至16倍,酶活力回收率可达86%。  相似文献   
67.
It is shown that in general the popular coefficient alpha estimator for reliability of multi-component measuring instruments converges almost surely to a quantity that is not equal to the population reliability coefficient. This convergence with probability 1 is a stronger statement than convergence in probability (consistency) and convergence in distribution for the alpha estimator, which have been studied in the past. In the special case of congeneric measures with uncorrelated errors and equal loadings on the common true score, the alpha estimator converges almost surely to the population reliability coefficient that equals population alpha, which implies also its consistency as a reliability estimator. When the loadings are unequal but sufficiently high and similar, the alpha estimator converges almost surely to population alpha that is essentially indistinguishable from the population reliability coefficient, which implies alpha’s approximate consistency then. For the general case, the results entail that the alpha estimator is not a consistent estimator of reliability. The findings add to the critical literature on coefficient alpha in the general case, as well as to the justification of its use as a dependable measuring instrument reliability estimator in special cases and settings resulting under appropriate restrictive conditions, and are illustrated using a numerical example.  相似文献   
68.
Cyclosporine has been reported to function as an inhibitor of the chymotrypsin like activity of proteasome. We hypothesized that the administration of an exogenous proteinase inhibitor may affect the activities of the naturally occurring serum anti proteinases. The aim of this study was to observe the pattern of alteration of serum alpha 2 macroglobulin (AMG), alpha 1- antitrypsin (AT) and alpha 1-antichymotrypsin (ACT) activities in renal transplant patients receiving the immunosuppressive drug, cyclosporine. Patients (97) who had received a single renal allograft were inducted into the study. Subjects were on a twice-daily dosage of cyclosporine capsules. Trough (Co) and two-hour post dose (C 2) cyclosporine levels were regularly estimated and all patients had stable creatinine levels. In 5 newly transplanted patients, antiproteinase activities were estimated weekly over a 4-week period as their cyclosporine doses were gradually tapered. Average serum activities of ACT and AMG in the transplant group were significantly less than in the control group (p<0.002 and p<0.003 respectively). AT and ACT activities fell gradually over 4 weeks. AMG activities showed a biphasic pattern, initially falling by almost 50% in the second week, increasing marginally in the third week and decreasing to less than 50% of the activities observed in the first week. Serum antiproteinase activities of serum alpha 2 macroglobulin (AMG), alpha 1-antitrypsin (AT) and alpha 1-antichymotrypsin (ACT) were found to be altered in renal transplant patients receiving cyclosporine.  相似文献   
69.
通过PCR扩增并克隆测序,获得了鳡(Elopichthys bambusa)线粒体ND5基因序列,该基因全长为1836bp,编码611个氨基酸残基的蛋白质,其起始密码子为ATG,终止密码子为TAA.分析该基因碱基组成及密码子使用情况,发现A+T含量高于G+C,并且在密码子第三位点存在明显的反G偏倚.将鳡ND5基因序列与GenBank中其他10个物种的ND5基因序列进行比对,结果表明鳡与鲢鱼的亲缘关系最近,青鱼次之.用NJ法构建11个物种的系统进化树,结果表明雅罗鱼亚科、鲌亚科和鲢亚科之间的亲缘关系很近,而鲤亚科与它们之间的亲缘关系相对较远.  相似文献   
70.
Creating a sense of community in online classes contributes to student retention and to their overall satisfaction with the course itself. This study aimed to develop a scale of sense of community of students attending online university courses. A series of ordinal exploratory factor analyses were conducted on data obtained from 839 students enrolled in Italian universities. Using an item analysis method, we were able to select the 36 most valid items from an original set of 60 items we had previously defined. These items are distributed across three related factors measuring membership, influence, and fulfillment of needs. This factorial structure replicates the McMillan and Chavis’s model of sense of community, upon the basis of which this scale was developed. The three factors presented good ordinal alpha and adequate convergent/divergent validity coefficients. The scale represents an efficient tool for the design, monitoring, and evaluation of online courses.  相似文献   
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