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91.
Mohamed Magdy Abdel-Moteleb 《Macromolecular chemistry and physics.》1991,192(3):543-551
The real part of the relative permittivity ?′r of some cellulosic materials contaminated with commercial impurities and NaCl (determined as weight percent ash contents), and that of the purified fibres, as well as their hydrolysed residues, free of such contaminations, was measured in the frequency range 102 Hz ≤ f ≤ 105 Hz and in the temperature range 283,15 K ≤ T ≤ 333,15 K. Additional measurements of the imaginary part of relative permittivity ?″r have been carried out in the same frequency and temperature ranges for hydrocellulose samples free of inorganic impurities and contaminated with NaCl. The results obtained show that the variation with temperature of the relative permittivity of the samples examined exhibits a change in slope in the vicinity of 303,15 K except for hydrocellulose samples free of impurities. They further show that the presence of inorganic contaminations has a significant effect on the magnitude of the relative permittivity and its variation with temperature, particularly at low frequency. In the case of samples contaminated with inorganic impurities, interfacial polarization is responsible for the anomalous dielectric behaviour observed with the examined samples. 相似文献
92.
Tlili A Charfedine I Lahmar I Benzina Z Mohamed BA Weil D Idriss N Drira M Masmoudi S Ayadi H 《Human mutation》2005,25(5):503
Approximately 80% of hereditary hearing loss is non-syndromic. Non-syndromic deafness is the most genetically heterogeneous trait. The most common and severe form of hereditary hearing impairment is autosomal recessive non-syndromic hearing loss (ARNSHL), accounting for approximately 80% of cases of genetic deafness. To date, 22 genes implicated in ARNSHL have been identified. Recently a gene, DFNB31/WHRN, which encodes a putative PDZ scaffold protein called whirlin, was found to be responsible for the ARNSHL DFNB31. We found evidence for linkage to the DFNB31locus in a consanguineous Tunisian family segregating congenital profound ARNSHL. Mutation screening of DFNB31/WHRNrevealed four nonpathogenic sequence variants and a novel frameshift mutation [c.2423delG] + [c.2423delG] that changed the reading frame and induced a novel stop codon at amino acid 818 ([p.Gly808AspfsX11] + [p.Gly808AspfsX11]). To determine the contribution of the DFNB31locus in the childhood deafness, we performed linkage analysis in 62 unrelated informative families affected with ARNSHL. No linkage was found to this locus. From this study, we concluded that DFNB31/WHRN is most likely to be a rare cause of ARNSHL in the Tunisian population. 相似文献
93.
94.
Vijay Gayam Venu M. Konala Srikanth Naramala Pavani Reddy Garlapati Mohamed A. Merghani Nirajan Regmi Mamtha Balla Sreedhar Adapa 《Journal of medical virology》2020,92(10):2181-2187
Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is spreading at a rapid pace, and the World Health Organization declared it as pandemic on 11 March 2020. Mycoplasma pneumoniae is an "atypical" bacterial pathogen commonly known to cause respiratory illness in humans. The coinfection from SARS-CoV-2 and mycoplasma pneumonia is rarely reported in the literature to the best of our knowledge. We present a study in which 6 of 350 patients confirmed with COVID-19 were also diagnosed with M. pneumoniae infection. In this study, we described the clinical characteristics of patients with coinfection. Common symptoms at the onset of illness included fever (six [100%] patients); five (83.3%) patients had a cough, shortness of breath, and fatigue. The other symptoms were myalgia (66.6%), gastrointestinal symptoms (33.3%-50%), and altered mental status (16.7%). The laboratory parameters include lymphopenia, elevated erythrocyte sedimentation rate, C-reactive protein, lactate dehydrogenase, interleukin-6, serum ferritin, and D-dimer in all six (100%) patients. The chest X-ray at presentation showed bilateral infiltrates in all the patients (100%). We also described electrocardiogram findings, complications, and treatment during hospitalization in detail. One patient died during the hospital course. 相似文献
95.
Protein composition of tomato spotted wilt virus 总被引:2,自引:0,他引:2
Analysis of the protein composition of tomato spotted wilt virus (TSWV), purified by an improved procedure, by polacrylamide gel electrophoresis, revealed three major structural proteins (of MW 84,000, 50,000, and 29,000d) and a minor one of MW 220,000d. The three major proteins constitute about 98% of the total viral protein and all three were shown to be glycoproteins. One of the major proteins (MW 29,000d) and the minor protein were shown to be associated with subviral particles isolated by treatment of virus with the nonionic detergent Nonidet P-40. Only traces of the other two proteins were detected in the subviral particles.Synthesis of virus-induced proteins in TSWV-infected tobacco leaves was studied by labeling infected and healthy tissue with [3H]and [14C]valine, respectively. The labeled tissues were then fractionated into crude subcellular fractions and protein patterns of healthy and infected tissues were compared by coelectrophoresis on polyacrylamide gels. Only one virus-specific protein (of MW 49,000d) was detected in the virus-enriched fractions; this corresponded with the viral structural protein of MW 50,000d. 相似文献
96.
Khaled K Abu-Amero Olayan M Al-Boudari Gamal H Mohamed Nduna Dzimiri 《BMC medical genetics》2006,7(1):52-5
Background
The E-selectin p. S128R (g. A561C) polymorphism has been associated with the presence of angiographic coronary artery disease (CAD) in some populations, but no data is currently available on its association with CAD in Arabs. 相似文献97.
Illigens BM Yamada A Fedoseyeva EV Anosova N Boisgerault F Valujskikh A Heeger PS Sayegh MH Boehm B Benichou G 《Human immunology》2002,63(10):912-925
In this study, we measured direct and indirect T-cell alloresponses mediated by CD4(+) and CD8(+) T cells in three mouse transplantation models: skin, cornea, and retina. We show that the contribution of direct and indirect antigen recognition pathways to the alloresponse to fully allogeneic grafts varies depending upon the nature of the tissue/organ transplanted. The implications of this finding for understanding the cellular mechanisms by which rejection is mediated in different transplant models are discussed. 相似文献
98.
99.
Nadine C. Milos Yanling Ma Parag V. Varma Michael P. Bering Zarina Mohamed Linda M. Pilarski Yvette N. Frunchak 《Anatomy and embryology》1990,182(4):319-327
Summary A monoclonal antibody has been produced againstXenopus laevis galactoside-binding neural-creststage lectin. This antibody inhibits lectin-mediated hemagglutination. Using this antibody
in conjunction with immunohistochemical techniques, lectin deposition has been studied in embryos and tadpoles at different
stages of morphogenesis, from initial neural crest migration, up to the formation of a swimming tadpole. Lectin levels change
during development in different regions of the embryo and tadpole, decreasing in migratory cells, and increasing in sites
where cells become more adhesive to one another. The results suggest that galactoside-binding lectins may be an important
class of cellular adhesion molecules during these stages of development. 相似文献
100.
Bedaiwy MA Goldberg JM Falcone T Singh M Nelson D Azab H Wang X Sharma R 《Human reproduction (Oxford, England)》2002,17(3):601-604
BACKGROUND: Oxidative stress mechanisms are involved in the pathophysiology of many reproductive disorders. The objective of this study was to characterize oxidative stress parameters in hydrosalpingeal fluid (HSF) and examine their possible role in early embryo development. METHODS AND RESULTS: HSF was aspirated at laparoscopic salpingectomy in 11 infertile women. Reactive oxygen species (ROS), total (non-enzymatic) antioxidant capacity (TAC) and lipid peroxidation (LPO) were assayed. Two-cell mouse embryos were incubated with 25, 50 or 75% HSF and the blastocyst development rate was observed. ROS was detected in five of 11 (45%) HSF samples with a mean of 4.2 x 10(4) c.p.m. LPO was detected in all samples at a mean (+/- SD) value of 5575.4 +/- 6091.9 micromol/l malonaldehyde. The mean blastocyst development rate at 25, 5+/- 0 and 75% HSF and in the control group was 88.9 +/- 9.4, 65.7 +/- 19.1, 45.7 +/- 5.7 and 96.7% respectively (P < 0.0001). The blastocyst development rate was positively correlated to ROS concentrations (P < 0.02) but was not significantly related to LPO. CONCLUSIONS: The blastocyst development rate decreased with increasing concentrations of HSF. For the first time, the presence of ROS, LPO and TAC activity in human HSF was characterized. A possible role of oxidative stress in the embryotoxicity of HSF is suggested. 相似文献