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41.
Esophageal cancer involves multiple genetic alternations. A systematic codon usage bias analysis was completed to investigate the bias among the esophageal cancer responsive genes. GC-rich genes were low (average effective number of codon value was 49.28). CAG and GTA are over-represented and under-represented codons, respectively. Correspondence analysis, neutrality plot, and parity rule 2 plot analysis confirmed the dominance over mutation pressure in modulating the codon usage pattern of genes linked with esophageal cancer.  相似文献   
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Powerful analyses of population structure require information from multiple genetic loci. To help develop a molecular toolbox for obtaining this information, we have designed universal oligonucleotide primers that span conserved intron-exon junctions in a wide variety of animal phyla. We test the utility of exon-primed, intron-crossing amplifications by analyzing the variability of actin intron sequences from humpback, blue, and bowhead whales and comparing the results with mitochondrial DNA (mtDNA) haplotype data. Humpback actin introns fall into two major clades that exist in different frequencies in different oceanic populations. It is surprising that Hawaii and California populations, which are very distinct in mtDNAs, are similar in actin intron alleles. This discrepancy between mtDNA and nuclear DNA results may be due either to differences in genetic drift in mitochondrial and nuclear genes or to preferential movement of males, which do not transmit mtDNA to offspring, between separate breeding grounds. Opposing mtDNA and nuclear DNA results can help clarify otherwise hidden patterns of structure in natural populations.   相似文献   
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The goal of this research is to compare the metal binding characteristics of an anoxic selector activated sludge system and a conventional activated sludge system. Metal biosorption by biomass harvested from experimental systems was determined by a series of batch experiments. Heavy metals studied in this research were zinc, cadmium, and nickel. The sorption isotherm showed that the selector sludge had significantly higher sorption capacity than did the control sludge. Metal biosorption behavior closely followed a Freundlich isotherm model for equilibrium concentrations. ECP contents of biomass estimated by alkali extraction technique showed that ECP levels in the selector sludge significantly higher than that in the sludge harvested from the conventional system, indicating that the higher metal sorption capacity of selector sludge may be due to the selection of the ECP-producing bacteria (i.e., Zoogloca sp.) by the selector system.  相似文献   
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The use of the antiplatelet agents abciximab and clopidogrel is now accepted therapy in percutaneous coronary intervention. We present a case in which these agents were used in a patient with idiopathic thrombocytopaenic purpura and a platelet count of 40x10(9)/l undergoing primary multivessel coronary stenting. This case shows that unstable coronary syndromes can occur in patients with thrombocytopaenia and that antiplatelet agents may be used safely in this context.  相似文献   
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SYNOPSIS. Ochromonas danica in a complex natural growth medium dies at 6–10 C in 4 days; O. malhamensis in ∼2 days. O. danica grown in the medium supplemented with 4.0% glycerol survived at −10±2 C for 35 days, and with 8% glycerol 29 days. O. malhamensis lasted only to 5 days in these media supplemented with 4% glycerol. Ethylene glycol and dimethylsulfoxide were too toxic to be effective. Difficulties in freeze-preservation of certain other phagocytic cells, notably blood granulocytes having comparatively simple flexuous outer membranes, add interest to use of O. danica and O. malhamensis as test organisms for preservation methods, especially in the convenient, inexpensive -10 to -20 C range. Biphasic media with an overlay of distilled water serve for conservation at room temperature. Problems of mutational erosion of these photosynthetic phagotrophs are discussed.  相似文献   
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