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151.
A new species group, the Protohermes fruhstorferi group of the dobsonfly genus Protohermes, is recognised. Three species belonging to the new species group are described and illustrated, including one new species from northern Vietnam. 相似文献
152.
Jovana Milanovic Sonja Schiehser Predrag Milanovic Antje Potthast Mirjana Kostic 《Carbohydrate polymers》2013
The effects of TEMPO-mediated oxidation, performed with NaClO, a catalytic amount of NaBr, and 2,2′,6,6′-tetramethylpiperidine-1-oxy radical (TEMPO), were studied on lyocell fibers by means of GPC using multiple detection and group-selective fluorescence labeling according to the CCOA and FDAM methodology. The applied method determines functional group content as a sum parameter, as well as functional group profiles in relation to the molecular weight of the cellulose fibers. Both the CHO and COOH profiles, as well as molecular weight alterations, were analyzed. A significant decrease in the average molecular weight was obtained during the first hour of TEMPO-mediated oxidation, but prolonged oxidation time resulted in no strong additional chain scission. Significant amounts of COOH groups were introduced in the high molecular weight fractions by the oxidation with higher concentrations of NaClO (2.42–9.67 mmol NaClO/g fiber) after modification times of 1 h or longer. 相似文献
153.
Exposure to chronic drugs of abuse has been reported to produce significant changes in postsynaptic protein profile, dendritic spine morphology and synaptic transmission. In the present study we demonstrate alterations in dendritic spine morphology in the frontal cortex and nucleus accumbens of mice following chronic morphine treatment as well as during abstinence for two months. Such alterations were accompanied with significant upregulation of the postsynaptic protein Shank1 in synaptosomal enriched fractions. mRNA levels of Shank1 was also markedly increased during morphine treatment and during withdrawal. Studies of the different postsynaptic proteins at the protein and mRNA levels showed significant alterations in the morphine treated groups compared to that of saline treated controls. Taken together, these observations suggest that Shank1 may have an important role in the regulation of spine morphology induced by chronic morphine leading to addiction. 相似文献
154.
Yong‐Chan Kwon In‐Seok Oh Nahum Lee Kyung‐Ho Lee Yeo Joon Yoon Eun Yeol Lee Byung‐Gee Kim Dong‐Myung Kim 《Biotechnology and bioengineering》2013,110(4):1193-1200
Harnessing the isolated protein synthesis machinery, cell‐free protein synthesis reproduces the cellular process of decoding genetic information in artificially controlled environments. More often than not, however, generation of functional proteins requires more than simple translation of genetic sequences. For instance, many of the industrially important enzymes require non‐protein prosthetic groups for biological activity. Herein, we report the complete cell‐free biogenesis of a heme prosthetic group and its integration with concurrent apoenzyme synthesis for the production of functional P450 monooxygenase. Step reactions required for the syntheses of apoenzyme and the prosthetic group have been designed so that these two separate pathways take place in the same reaction mixture, being insulated from each other. Combined pathways for the synthesis of functional P450 monooxygenase were then further integrated with in situ assay reactions to enable real‐time measurement of enzymatic activity during its synthesis. Biotechnol. Bioeng. 2013; 110: 1193–1200. © 2012 Wiley Periodicals, Inc. 相似文献
155.
Fernando A. Villanea Deborah A. Bolnick Cara Monroe Rosita Worl Rosemary Cambra Alan Leventhal Brian M. Kemp 《American journal of physical anthropology》2013,151(4):649-657
In this study, we explore the geographic and temporal distribution of a unique variant of the O blood group allele called O1vG542A, which has been shown to be shared among Native Americans but is rare in other populations. O1vG542A was previously reported in Native American populations in Mesoamerica and South America, and has been proposed as an ancestry informative marker. We investigated whether this allele is also found in the Tlingit and Haida, two contemporary indigenous populations from Alaska, and a pre‐Columbian population from California. If O1vG542A is present in Na‐Dene speakers (i.e., Tlingits), it would indicate that Na‐Dene speaking groups share close ancestry with other Native American groups and support a Beringian origin of the allele, consistent with the Beringian Incubation Model. If O1vG542A is found in pre‐Columbian populations, it would further support a Beringian origin of the allele, rather than a more recent introduction of the allele into the Americas via gene flow from one or more populations which have admixed with Native Americans over the past five centuries. We identified this allele in one Na‐Dene population at a frequency of 0.11, and one ancient California population at a frequency of 0.20. Our results support a Beringian origin of O1vG542A, which is distributed today among all Native American groups that have been genotyped in appreciable numbers at this locus. This result is consistent with the hypothesis that Na‐Dene and other Native American populations primarily derive their ancestry from a single source population. Am J Phys Anthropol 151:649–657, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
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158.
Filbert Totsingan Anthony J. Bell Jr 《Protein science : a publication of the Protein Society》2013,22(11):1552-1562
The objective of this study was to evaluate the effects of inserting peptide nucleic acid (PNA) sequences into the protein‐binding surface of an immobilized four‐way junction (4WJ). Here we compare the classic immobile DNA junction, J1, with two PNA containing hybrid junctions (4WJ‐PNA1 and 4WJ‐PNA3). The protein interactions of each 4WJ were evaluated using recombinant high mobility group proteins from rat (HMGB1b and HMGB1b/R26A) and human histone H1. In vitro studies show that both HMG and H1 proteins display high binding affinity toward 4WJ's. A 4WJ can access different conformations depending on ionic environment, most simply interpreted by a two‐state equilibrium between: (i) an open‐x state favored by absence of Mg2+, low salt, and protein binding, and (ii) a compact stacked‐x state favored by Mg2+. 4WJ‐PNA3, like J1, shifts readily from an open to stacked conformation in the presence of Mg+2, while 4WJ‐PNA1 does not. Circular dichroism spectra indicate that HMGB1b recognizes each of the hybrid junctions. H1, however, displays a strong preference for J1 relative to the hybrids. More extensive binding analysis revealed that HMGB1b binds J1 and 4WJ‐PNA3 with nearly identical affinity (KDs) and 4WJ‐PNA1 with two‐fold lower affinity. Thus both the sequence/location of the PNA sequence and the protein determine the structural and protein recognition properties of 4WJs. 相似文献
159.
目的:探讨新生溶血病患儿红细胞致敏抗体对其Rh血型鉴定的影响。方法:采用抗球蛋白法、盐水法、微柱凝胶法(Rh血型测定型)、凝聚胺法和抗血清微柱凝胶法(Ig G型)五种方法对近三年来我院收集的163例新生溶血病患儿红细胞进行Rh血型检测,对五种检测结果不一致的患儿红细胞进行0.2 M 2-巯基乙醇抗体放散,比较放散后五种方法检测结果并验证其准确性。结果:29例直接抗体试验阳性患儿的五种Rh血型检测结果不一致,经0.2 M 2-巯基乙醇抗体放散后检测结果均一致。Rh血型准确性验证表明,红细胞放散测定的Rh血型完全符合临床现象。结论:患儿红细胞的致敏抗体达一定数量后,会影响抗球蛋白法、盐水法、微柱凝胶法(Rh血型测定型)、凝聚胺法和抗血清微柱凝胶法(Ig G型)对Rh血型鉴定,0.2M 2-巯基乙醇抗体放散法是一种正确鉴定新生儿Rh血型的简单可行的方法。 相似文献
160.