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11.
Complementation analyses of radiation-induced deletion mutations involving the albino (c) locus in Chromosome (Chr) 7 of the mouse have identified several loci, in addition toc, that have important roles in development. The mesoderm-deficient (msd) and hepatocyte-specific developmental regulation-1 (hsdr-1) loci, which are proximal and tightly linked toc, are important in the formation of mesoderm and in the regulation of liver- and kidney-specific induction of various enzymes and proteins, respectively. Cloning deletion-breakpoint-fusion fragments caused by lethal albino deletions that genetically define the extents of themsd andhsdr-1 loci is one way of generating molecular probes for studying the gene(s) involved in these phenotypes. The distal breakpoints of five such deletions were positioned on a long-range (PFGE) map of 1.7 Mb of wild-type DNA surrounding thec, D7Was12, andEmv-23 loci. In addition, the distal breakpoints of two viable albino deletions, which remove part of the tyrosinase gene and extend distally, were localized in the vicinity of the lethal deletion breakpoints. Therefore, the viable deletions can be exploited to generate additional DNA probes that should facilitate the isolation of breakpoint clones from chromosomes carrying lethal deletions defininghsdr-1 andmsd. 相似文献
12.
A.D. Saad B.M. Soh A.A. Moscona 《Biochemical and biophysical research communications》1981,98(3):701-708
Cortisol induces glutamine synthetase (GS) in neural retina tissue of chick embryos. GS induction represents a characteristic feature of embryonic retina differentiation. However, if the tissue is dissociated into single cells, the dispersed cells are not inducible for GS. We report that cell dispersion results in a rapid and marked reduction in the level of cortisol-binding cytoplasmic receptors. This reduction persists if the cells are maintained in a dispersed state. However, if the cells are reaggregated and they reconstruct tissue-like contacts and architecture, the level of cortisol receptors increases, and so does inducibility for GS. The results indicate that, in the embryonic neural retina histotypic cell contacts and interactions are involved in regulating the level of cortisol receptors. We propose that cell contact-dependent signals from the cell surface may modulate levels of cytoplasmic cortisol receptors necessary for GS induction. 相似文献
13.
Hydrolysis of 1,2-O-isopropylidene-3,5-di-O-methyl-α-d-glucofuranose by strong acid yielded 3,5-di-O-methyl-d-glucofuranose (6) and its 1,6-anhydride (10). The mechanism of the reaction giving 10 is discussed. On treatment with a catalytic amount of sodium methoxide, 1,2,6-tri-O-acetyl-3,5-di-O-methyl-d-glucofuranose (8) gives the 6-O-acetyl derivative, whereas complete deacetylation, and subsequent isomerization to the d-fructose derivative 16, takes place in the presence of 0.1m sodium methoxide. The structure of 16 was proved both chemically and spectroscopically. Reduction of 6 or 8 with a borohydride afforded 3,5-di-O-methyl-d-glucitol.2 相似文献
14.
Young Moon Choi Byoung Wan Lee Myung Sun Jung Hyun Soo Han Suk Hyun Kim Kaifeng Chen Dong Ha Kim Tony F. Heinz Shanhui Fan Jihye Lee Gi‐Ra Yi Jung Kyu Kim Jong Hyeok Park 《Liver Transplantation》2020,10(22)
N‐type metal oxides such as hematite (α‐Fe2O3) and bismuth vanadate (BiVO4) are promising candidate materials for efficient photoelectrochemical water splitting; however, their short minority carrier diffusion length and restricted carrier lifetime result in undesired rapid charge recombination. Herein, a 2D arranged globular Au nanosphere (NS) monolayer array with a highly ordered hexagonal hole pattern (hereafter, Au array) is introduced onto the surface of photoanodes comprised of metal oxide films via a facile drying and transfer‐printing process. Through plasmon‐induced resonance energy transfer, the Au array provides a strong electromagnetic field in the near‐surface area of the metal oxide film. The near‐field coupling interaction and amplification of the electromagnetic field suppress the charge recombination with long‐lived photogenerated holes and simultaneously enhance the light harvesting and charge transfer efficiencies. Consequently, an over 3.3‐fold higher photocurrent density at 1.23 V versus reversible hydrogen electrode (RHE) is achieved for the Au array/α‐Fe2O3. Furthermore, the high versatility of this transfer printing of Au arrays is demonstrated by introducing it on the molybdenum‐doped BiVO4 film, resulting in 1.5‐fold higher photocurrent density at 1.23 V versus RHE. The tailored metal film design can provide a potential strategy for the versatile application in various light‐mediated energy conversion and optoelectronic devices. 相似文献
15.
We carried out DNA barcoding on 24 Korean tettigonid species of 19 genera deposited in the National Institute of Biological Resources to reevaluate the preliminary identification of each specimen. Sequence divergence of DNA barcodes obtained from 113 samples of the 24 species ranged from 0 to 30.4%, the intraspecific variation was 0–7.3%, and the interspecific divergence was 1.1–30.4%; we could not examine the barcoding gap. In the neighbor‐joining tree, the branch length among individuals of Tettigonia ussuriana, Paratlanticus ussuriensis, and Hexacentrus japonicus were relatively longer than those in other species. The detailed analysis of the morphological characters and DNA barcodes of the above three species revealed that these three species represent species complexes. The T. ussuriana complex comprised T. jungi, T. uvarovi, and T. ussuriana. Paratlanticus ussuriensis cluster contained four species; one cluster was identified as P. palgongensis based on morphological characteristics, but the other three clusters, including the P. ussuriensis cluster, require further detailed taxonomic analysis. Lastly, two species clusters were identified within the Hexacentrus japonicus clade. Based on the 99% sequence similarity obtained by blast search of the NCBI GenBank database, one of the clusters was identified as H. unicolor. Thus, the DNA barcoding revealed the presence of at least three cryptic species in Korean Tettigoniidae, although more detailed taxonomic analyses are required to establish their status. Therefore, we suggest that DNA barcoding is a very useful tool for increasing the identification accuracy of insect collections. 相似文献
16.
17.
Since 1858, when Hitchcock first recorded dinosaur tail traces from the Jurassic of Massachusetts, USA, a number of dinosaur tail traces have been reported. Although considered rare, at least 38 records of dinosaur tail traces have previously been reported in the literature. These occurrences are herein reviewed in order to understand their geographic and stratigraphic distribution, types of tail trace makers, and characteristics of dinosaur tail traces. Several terms for dinosaur tail traces have been employed and they are divided into tail impressions (TIs) for resting traces, and tail drag impressions (TDIs) for locomotion traces. Possible criteria for distinguishing, measuring and comparing TIs and TDIs are suggested. In addition, herringbone structures, one of the characteristic features of tail traces associated with ornithopod and theropod tracks, are discussed. Estimated speeds of tail trace makers are shown to be rather low. Finally, the abundance of tail traces associated with bipedal, rather than quadrupedal, dinosaurs is considered a reflection of behavior. 相似文献
18.
Although more than 60 ancient hominid track sites ranging in age from 3.7 million to less than 500 B. P. are recorded from all continents except Antarctica, no ichnotaxonomic names have ever been formally proposed for hominid tracks. There is no prohibition to the naming of fossil footprints of species that created tracks and trackways similar to those of living species. On the contrary, there is precedent for the naming of ichnotaxa corresponding to the dominant extant vertebrates classes: mammals = Mammalipedia and birds = Avipeda. The hominid track site sample includes only about a dozen sites where footprint preservation is good enough to show details of diagnostic foot morphology and typical trackway morphology. We infer that the Acahualinca Footprint Museum site in Nicaragua represents the most important ancient hominid track site that combines accessibility, a large sample of well-preserved trackways and reliable dating. For this reason, we select the Nicaraguan tracks as the type sample for the new ichnotaxon Hominipes modernus ichnogen., and ichnsp. et ichnosp. nov., which we infer to represent fully modern Homo sapiens. Our preliminary investigations of other track sites suggest that the majority also yield H. modernus. However, at many sites preservation is insufficient to make an ichnotaxonomic designation at the species level or to infer that the trackmaker was H. sapiens. Thus, at many sites including the famous Laetoli site, we apply the more general label of Hominipes isp. indet. 相似文献
19.
Jong Chul Won Yun Jeong Lee Jung Min Kim Sang Youb Han Jung Hyun Noh Kyung Soo Ko Byoung Doo Rhee Dong-Jun Kim 《PloS one》2013,8(12)
Background
Microalbuminuria is associated with increased risk of renal disease and cardiovascular diseases even in non-diabetic subjects. High incidence rates of microalbuminuria have been found in a number of population-based studies. However, the prevalence and risk factors associated with microalbuminuria in the general population in Korea are unclear.Objectives
The present study was performed to estimate the prevalence of microalbuminuria and investigate the associated risk factors in the general adult population using the Fifth Korea National Health and Nutrition Examination Survey (KNHANES V-2) data from 2011.Methods
A total of 5,202 participants (mean age, 45.6 years; men, 2,337; women, 2,865) were included in the analysis. Microalbuminuria was evaluated in participants of KNHANES V-2 based on the urine albumin–creatinine ratio. Estimated glomerular filtration rate was calculated using the Modification of Diet in Renal Disease study equation.Results
The weighted prevalence of microalbuminuria was 5.2% (95% CI, 4.4–6.1) in the general population. The prevalence of albuminuria is increased with age. After adjustment for age and sex, the presence of albuminuria was associated with increased waist circumference, systolic and diastolic blood pressure, aspartate aminotransferase, triglyceride, fasting plasma glucose, and the presence of hypertension and diabetes. In logistic regression analyses, older age, female sex, diabetes, hypertension, and serum aspartate aminotransferase were independently associated with the presence of albuminuria.Conclusion
The prevalence of microalbuminuria was found to be 5.2%, and conventional risk factors for cardiovascular diseases are closely related to the presence of microalbuminuria in Korea. Microalbuminuria may be a useful marker to identify individuals with increased risk of cardiovascular disease. 相似文献20.
Seung Mi Lee Jeong Woo Park Byoung Jae Kim Chan-Wook Park Joong Shin Park Jong Kwan Jun Bo Hyun Yoon 《PloS one》2013,8(12)