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High Resolving Power (high + resolving_power)
Selected AbstractsStudy on minute surface structures of the depressed-type early gastric cancer with magnifying endoscopyDIGESTIVE ENDOSCOPY, Issue 3 2001Kouji Tobita Background: Gastric surface patterns and morphology of minute surface vessels in depressed lesions were analyzed using a magnifying endoscope with high resolving power to contribute to qualitative diagnosis of gastric cancer. Methods: Subjects were diagnosed with depressed-type early gastric cancer (pT1), there were 63 lesions, 38 differentiated-type lesions, and 25 undifferentiated-type lesions. There were also 40 benign depressed lesions found. After routine observations with an endoscope, amplifying observations of lesions were made by EG-410CR (Fuji Photo Optical; Saitama, Japan) (CR). The images were compared with macroscopic patterns and histopathological patterns of the surgical specimens and endoscopic mucosal resection specimens. Results: Surface patterns of gastric depressed lesions were classified as irregular protrusion, normal papilla, pseudopapilla and amorphia. Irregular protrusion was found only in cancerous lesions. Characteristic minute vessels were observed in amorphia. Their patterns were classified into the following six types: sand, fence, round net, flat net, branch and coil. Irregular protrusion and minute vessels in amorphia (round net, flat net, branch and coil) were specific to cancers. There was a tendency for round net and flat net patterns to be found often in differentiated cancers and for branch and coil patterns to be found often in undifferentiated cancers. Conclusion: This magnifying endoscopic classification is considered useful for the qualitative diagnosis of depressed-type early gastric cancer. [source] DNA fragment analysis by an affordable multiple-channel capillary electrophoresis systemELECTROPHORESIS, Issue 1-2 2003Ming S. Liu Abstract We are demonstrating a cost-effective multichannel capillary electrophoresis system for a high-efficiency double-stranded DNA (dsDNA) fragments analysis. This bench-type high-performance DNA analysis (HDAÔ) system uses fluorescence-type detection with inexpensive solid-state light sources and nonmoving integrated emission collection micro-optics. DNA samples are analyzed simultaneously by using a multiple usage and disposable multicapillary cartridge, which contains integrated capillary channels, optical fibers and an integrated sieving gel reservoir. Using commercially available dsDNA size markers as indicators, the HDAÔ system provides high resolving power in 7 min separations. The system can hold a total of 192 samples in two 96-well polymerase chain reaction (PCR) plates, which can be automatically analyzed within 2.5 h. This affordable system can be used in laboratories to replace slab gel electrophoresis for routine and high-throughput dsDNA analysis. [source] Performance of the atomic and molecular physics beamline at the National Synchrotron Radiation LaboratoryJOURNAL OF SYNCHROTRON RADIATION, Issue 6 2006Sisheng Wang At the National Synchrotron Radiation Laboratory, The University of Science and Technology of China, an atomic and molecular physics beamline with an energy range of 7.5,124,eV has been constructed for studying the spectroscopy and dynamics of atoms, molecules and clusters. The undulator-based beamline, with a high-resolution spherical-grating monochromator (SGM), is connected to the atomic and molecular physics end-station. This end-station includes a main experimental chamber for photoionization studies and an additional multi-stage photoionization chamber for photoabsorption spectroscopy. A mid-photon flux of 5 × 1012,photons,s,1 and a high resolving power is provided by this SGM beamline in the energy range 7.5,124,eV. The size of the synchrotron radiation beam spot at the sample is about 0.5,mm in the vertical direction and 1.0,mm in the horizontal direction. Some experimental results of photoionization efficiency spectroscopy and photoabsorption spectroscopy of atoms and molecules are also reported. [source] Power for detecting genetic divergence: differences between statistical methods and marker lociMOLECULAR ECOLOGY, Issue 8 2006NILS RYMAN Abstract Information on statistical power is critical when planning investigations and evaluating empirical data, but actual power estimates are rarely presented in population genetic studies. We used computer simulations to assess and evaluate power when testing for genetic differentiation at multiple loci through combining test statistics or P values obtained by four different statistical approaches, viz. Pearson's chi-square, the log-likelihood ratio G -test, Fisher's exact test, and an FST -based permutation test. Factors considered in the comparisons include the number of samples, their size, and the number and type of genetic marker loci. It is shown that power for detecting divergence may be substantial for frequently used sample sizes and sets of markers, also at quite low levels of differentiation. The choice of statistical method may be critical, though. For multi-allelic loci such as microsatellites, combining exact P values using Fisher's method is robust and generally provides a high resolving power. In contrast, for few-allele loci (e.g. allozymes and single nucleotide polymorphisms) and when making pairwise sample comparisons, this approach may yield a remarkably low power. In such situations chi-square typically represents a better alternative. The G -test without Williams's correction frequently tends to provide an unduly high proportion of false significances, and results from this test should be interpreted with great care. Our results are not confined to population genetic analyses but applicable to contingency testing in general. [source] Extensive intraspecific polymorphism detected by SSCP at the nuclear C- mos gene in the endemic Iberian lizard Lacerta schreiberiMOLECULAR ECOLOGY, Issue 3 2006RAQUEL GODINHO Abstract C- mos is a highly conserved intronless gene that has proved useful in the analysis of ancient phylogenetic relationships within vertebrates. We selected the Iberian endemic Schreiber's green lizard (Lacerta schreiberi) that persisted in allopatric refugia since the late Pliocene to investigate the utility of the C- mos nuclear gene for intraspecific phylogeographic studies. Our combination of DNA sequencing with the high resolving power of single-strand conformational polymorphism (SSCP) effectively discriminated four common alleles showing strong population structuring (FST = 0.46). In addition, reconstruction of allele phylogenetic relationships further improved our understanding of C- mos spatial patterns of variation and allowed a comparison with previously described mitochondrial DNA data. Finally, limited sequencing of an extended C- mos fragment in six additional Lacerta species showed extensive polymorphism, to our knowledge representing a rare example of variation in a highly conserved nuclear gene. [source] Analysis of glycosaminoglycan-derived disaccharides in biologic samples by capillary electrophoresis and protocol for sequencing glycosaminoglycansBIOMEDICAL CHROMATOGRAPHY, Issue 2 2002F. N. Lamari Glycosaminoglycans are biologically significant carbohydrates which either as free chains (hyaluronan) or constituents of proteoglycans (chondroitin/dermatan sulfates, heparin, heparan sulfate and keratan sulfate) participate and regulate several cellular events and (patho)physiological processes. Capillary electrophoresis, due to its high resolving power and sensitivity, has been successfully used for the analysis of glycosaminoglycans. Determination of compositional characteristics, such as disaccharide sulfation pattern, is a useful prerequisite for elucidating the interactions of glycosaminoglycans with matrix effective molecules and, therefore, essential in understanding the biological functions of proteoglycans. The interest in the field of characterization of such biologically important carbohydrates is soaring and advances in this field will signal a new revolution in the area of glycomics equivalent to that of genomics and proteomics. This review focuses on the capillary electrophoresis methods used to determine the disaccharide pattern of glycosaminoglycans in various biologic samples as well as advances in the sequence analysis of glycosaminoglycans using both chromatographic and electrophoretic techniques. Copyright © 2002 John Wiley & Sons, Ltd. 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