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During DNA sequence analysis of cosmid L373 from the Mycobacterium leprae genome, an open reading frame of 1.4 kb encoding a protein with some homology to the immunodominant 34-kDa protein of Mycobacterium paratuberculosis, but lacking significant serological activity, was detected. The DNA sequence predicted a signal peptide with a modified lipoprotein consensus sequence, but the protein proved to be devoid of lipid attachment.  相似文献   
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The presence of IgE receptor FcεRIβ polymorphism (181/183) was investigated in Kuwaiti asthmatic patients and controls using an allele refractory mutation screening (ARMS) test. The variant sequence (Leu181/Leu183) was detected in 72% (320/442) chromosomes analysed. Homozygous LL genotype was detected in 48% (46/96) asthmatic subjects compared to 31% (39/125) in non-asthmatics. In 11/52 families mothers of the asthmatic children were themselves asthmatic and 3/11 asthmatic mothers had homozygous LL genotype. 80% of the homozygous LL asthmatics showed a positive skin prick test (SPT) compared with 28% of non-asthmatics with the same genotype. In heterozygous NL asthmatics a positive SPT was found in 60% cases compared to 17% in non asthmatics with the same genotype. The incidence of hay fever (HF) and eczema (E) was also found to be higher in homozygous LL asthmatics compared with the non-asthmatics with the same genotype. This study reports a high prevalence of IgE receptor FcεRIβ variants in Kuwaiti Arabs compared with British, Australian and Austrian populations studied before. The association of Leu181/Leu183 variant with asthma in Kuwaitis underlines its significance as a risk factor in manifesting the clinical phenotype in this population.  相似文献   
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In this paper, Sr2Ni1−xZnxTeO6 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) double perovskite compounds were synthesised by the conventional solid-state method, and the structural, optical and dielectric properties were investigated. The Rietveld refinement of X-ray diffraction data shows that all compounds were crystallised in monoclinic symmetry with the I2/m space group. Morphological scanning electron microscopy reported that the grain sizes decreased as the dopant increased. The UV-vis diffuse reflectance spectroscopy conducted for all samples found that the optical band gap energy, Eg, increased from 3.71 eV to 4.14 eV. The dielectric permittivity ε′ values increased for the highest Zn-doped composition, Sr2Ni0.2Zn0.8TeO6, being ∼1000 and ∼60 in the low- and high-frequency range, respectively. All samples exhibited low dielectric loss (tan δ ≤ 0.20) in the range of 104–105 Hz frequency. Impedance measurement revealed that grain resistance decreased with enhancement in Zn content in the Sr2NiTeO6 crystal lattice.

In this paper, Sr2Ni1−xZnxTeO6 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) double perovskite compounds were synthesised by the conventional solid-state method, and the structural, optical and dielectric properties were investigated.  相似文献   
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BACKGROUND: Heart murmurs are common in the elderly and increased intracavitary velocities (IIV) within the left ventricle have been reported to be a cause of systolic murmur. OBJECTIVE: To assess the prevalence and functional significance of IIV in healthy elderly subjects METHODS: Ambulatory healthy elderly subjects were recruited from community centres and seniors' apartments. They were screened using a structured questionnaire and then underwent a comprehensive history and physical examination. Electrocardiogram, echocardiogram and 6-min walk test were performed on the same day. RESULTS: Four of the 88 subjects were excluded because of significant valvular dysfunction. Ten of the remaining 84 subjects had IIV and their demographics were similar to those of the 74 subjects without IIV. Echocardiographic parameters including left ventricular size and mass were similar between the two groups. Left ventricular mass index was lower in subjects with IIV (P=0.02). Both groups had similar 6-min walk results. CONCLUSIONS: In the healthy elderly who do not have valvular disease or left ventricular hypertrophy, IIV is uncommon and does not appear to have functional significance.  相似文献   
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A simple, cost-effective, and environmentally friendly method is needed for synthesizing metal nanoparticles, including gold nanoparticles (AuNPs). In this study, AuNPs were synthesized with Lignosus rhinocerotis sclerotial extract (LRE) and chitosan (CS) as reducing and stabilizing agents, respectively. Different LRE concentrations from cold and hot water extraction (CWE and HWE, respectively) were used to reduce chloroauric acid (HAuCl4) to form AuNPs. Positively charged chitosan stabilized AuNPs (CS-AuNPs) mediated by LRE exhibited a surface plasmon resonance (SPR) band at 533?nm. The CS-AuNPs synthesized using CWE had a smaller particle size (49.5?±?6.7–82.4?±?28.0?nm) compared to that of the HWE samples (80.3?±?23.4–125.3?±?41.5?nm), depending on LRE concentration. FTIR results suggested protein and polysaccharides in LRE were the sources of reducing power, reducing gold ions to AuNPs. CS-AuNPs were mostly spherical with higher LRE concentrations, whereas some triangular, pentagonal, irregular, and rod shaped AuNPs were observed at lower LRE concentrations. CS-AuNPs mediated by LRE displayed effective antibacterial activity against gram-negative (Pseudomonas aeruginosa and Escherichia coli) and gram-positive bacteria (Staphylococcus aureus and Bacillus sp.). Thus, the biosynthesized AuNPs using LRE and chitosan provide opportunities for developing stable and eco-friendly nanoparticles with effective antibacterial properties.  相似文献   
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Objective:To identify factors that are associated with sports participation following spinal cord injury (SCI).Study Design:Case–control study.Setting:Spinal Rehabilitation outpatient clinic in a tertiary hospital in Kuala Lumpur, Malaysia.Participants:Thirty-one sports participants (SP) and thirty-four non-sports participants (NSP) (N = 65) met the following inclusion criteria; chronic SCI more than one year, age between 18 and 50 years, both traumatic and non-traumatic SCI at C5 level and below, complete or incomplete SCI (AIS A-D) and mobilizing with either manual or motorized wheelchair independently.Methods:Face-to-face interviews were performed with a 22-item self-constructed questionnaire which contained four domains of variables; socio-demographic, SCI-related, environmental and sports-related factors. Data collection was done between June 2017 and May 2018.Results:Traumatic SCI, pre-injury interest in sports, pre-injury sports participation, ability to drive own vehicles, and being employed were significantly associated with sports participation post-SCI (p < 0.05). Multiple logistic regression revealed traumatic SCI (p = 0.012, OR 34.70, CI 2.21–545.90) and pre-injury interest in sports (p = 0.046, OR 29.10, CI 1.06–798.95) to be independent predictors of sports participation post-SCI.Conclusion:Traumatic SCI and pre-injury interest in sports were predictors of sports participation post-SCI. Pre-injury sports participation, being employed, and the ability to drive own vehicles were positively associated with sports participation. Findings from this study suggest a few crucial differences in facilitators and barriers to sports participation in Malaysia compared to other countries.  相似文献   
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