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EKLF/KLF1 was the first of the Krüppel-like factors (KLFs) to be identified in mammals and plays an important role in primitive and definitive erythropoiesis. Here, we identify and characterize EKLF in the chicken (cEKLF). The predicted amino acid sequence of the zinc finger region of cEKLF is at least 87.7% similar to mammalian EKLF proteins and is 98.8% and 95% similar to the EKLF orthologues in Xenopus and zebrafish, respectively. During early embryonic development, cEKLF expression is seen in the posterior primitive streak, which gives rise to hematopoietic cells, and then in the blood islands and in circulating blood cells. cEKLF mRNA is expressed in blood cells but not in brain later in chicken embryonic development. cEKLF mRNA is increased in definitive compared with primitive erythropoiesis. The conserved sequence and expression pattern of cEKLF suggests that its function is similar to its orthologues in mammals, Xenopus, and zebrafish.  相似文献   
94.
We evaluated the molecular mechanism for resistance of 360 enterococci for which the gentamicin MICs were >/=128 micro g/ml. The aac(6')-Ie-aph(2")-Ia, aph(2")-Ic, and aph(2")-Id genes were identified by PCR in isolates from animals, food, and humans. The aph(2")-Ib gene was not identified in any of the isolates. Two Enterococcus faecalis isolates (MICs > 1,024 micro g/ml) from animals failed to generate a PCR product for any of the genes tested and likely contain a new unidentified aminoglycoside resistance gene. Pulsed-field gel electrophoresis (PFGE) analysis showed a diversity of strains. However, 1 human and 18 pork E. faecalis isolates from Michigan with the aac(6')-Ie-aph(2")-Ia gene had related PFGE patterns and 2 E. faecalis isolates from Oregon (1 human and 1 grocery store chicken isolate) had indistinguishable PFGE patterns. We found that when a gentamicin-resistant gene was present in resistant enterococci from animals, that gene was also present in enterococci isolated from food products of the same animal species. Although these data indicate much diversity among gentamicin-resistant enterococci, the data also suggest similarities in gentamicin resistance among enterococci isolated from humans, retail food, and farm animals from geographically diverse areas and provide evidence of the spread of gentamicin-resistant enterococci from animals to humans through the food supply.  相似文献   
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The origin of the raised serum IgG3 in primary biliary cirrhosis has been examined. Blood lymphocytes from patients with PBC and from age- and sex-matched controls were cultured, and the culture supernatants were assayed for IgG and IgG3. Lymphocytes from PBC patients spontaneously synthesized a higher percentage IgG3/total IgG than did control lymphocytes, as determined by ELISA. The increased synthesis of IgG3 in culture correlated with serum IgG3 in the patients. This strongly suggests that the raised serum IgG3 in these patients is due to increased synthesis of this isotype. Following PWM stimulation, the proportion of IgG3/IgG synthesized by normal (and most PBC) lymphocytes increased and the difference in IgG3 synthesized by PBC and control lymphocytes became less marked. The kappa/lambda light chain ratio of the IgG3 was assayed by ELISA but no evidence was found for clonally restricted synthesis of IgG3 by PBC blood lymphocytes.  相似文献   
97.
Eighty-eight adult female rats were fed diets containing either 0.08, 0.12, 1, 3, or 4% NaCl for at least one week prior to breeding and throughout gestation. Within 24 hours of birth, all pups were sexed based on anogenital distance, and the number of males and females were recorded. The amount of sodium chloride in mother rats' diets was inversely related to the proportion of phenotypic males in the litter. As dietary salt increased, the proportion of males decreased. These alterations in dietary NaCl affected the sex ratio without disrupting litter size or the general health of the offspring. Dietary mineral content may affect the phenotypic sex ratio through changes in the genotypic sex ratio, or alternatively, via changes in the environment in which the genes are expressed. These findings are important for basic research concerning maternal nutrition and development.  相似文献   
98.
Sorsby fundus dystrophy is an autosomal dominant disorder which both clinically and histopathologically bears striking similarities to age related macular degeneration, one of the leading causes of blindness in the developed world. Recent studies have suggested a genetic localisation of the disease to chromosome 22q in a large genetic interval of approximately 25 cM. Independent genetic linkage analysis in a six generation British pedigree confirms linkage to the chromosome 22q region. A maximum two point lod score of 7.09 with no recombination was obtained with marker D22S280. Haplotype data positioned the disease between loci D22S275 and D22S278, thus significantly reducing the region on chromosome 22q where the gene is located.  相似文献   
99.
The antimicrobial susceptibilities of 100 clinical isolates of Pseudomonas aeruginosa to gentamicin, amikacin, tobramycin, ticarcillin, piperacillin, and ceftazidime were determined by using the Sceptor system (BBL Microbiology Systems, Cockeysville, Md.), and the results were compared with those obtained using the National Committee for Clinical Laboratory Standards reference agar dilution method. Excellent correlation was observed for the aminoglycosides, with greater than 95% agreement within 1 doubling dilution of the reference agar dilution MIC, while ticarcillin and piperacillin showed lower percent agreement values of 91 and 88%, respectively.  相似文献   
100.
Angelman syndrome (AS) is caused by several genetic mechanisms that impair the expression of maternally‐inherited UBE3A through deletions, paternal uniparental disomy (UPD), UBE3A pathogenic variants, or imprinting defects. Current methods of differentiating the etiology require molecular testing, which is sometimes difficult to obtain. Recently, computer‐based facial analysis systems have been used to assist in identifying genetic conditions based on facial phenotypes. We sought to understand if the facial‐recognition system DeepGestalt could find differences in phenotype between molecular subtypes of AS. Images and molecular data on 261 individuals with AS ranging from 10 months through 32 years were analyzed by DeepGestalt in a cross‐validation model with receiver operating characteristic (ROC) curves generated. The area under the curve (AUC) of the ROC for each molecular subtype was compared and ranked from least to greatest differentiable phenotype. We determined that DeepGestalt demonstrated a high degree of discrimination between the deletion subtype and UPD or imprinting defects, and a lower degree of discrimination with the UBE3A pathogenic variants subtype. Our findings suggest that DeepGestalt can recognize subclinical differences in phenotype based on etiology and may provide decision support for testing.  相似文献   
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