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71.
Haejeen Bang Dong Youn Cho Kil-Sun Yoo Moo-Kyoung Yoon Bhimanagouda S. Patil Sunggil Kim 《Euphytica》2011,179(3):439-449
In order to implement reliable marker-assisted selection systems for the restorer-of-fertility locus (Ms) in onions (Allium cepa L.), simple PCR-based codominant markers linked to the Ms locus were developed. Based on the EST probe sequences of previously reported RFLP markers, full-length genomic sequences
of the gene encoding putative oligopeptide transporter (OPT) was obtained by RACE. The first intron contained two 108 and
439-bp indel polymorphisms between the two Ms allele-linked OPT alleles. A simple PCR marker for OPT was developed by designing a primer pair on the flanking regions of
the 108-bp indel which is created by two tandem repeats. The second simple PCR marker was developed from the EST probe encoding
photosystem I subunit O (PsaO). Two 14 and 39-bp tandem repeats were identified from the 5′ upstream sequences of the PsaO-coding
gene, which were isolated by genome walking. Three different compositions of these tandem repeats were identified from diverse
onion germplasm. A primer set binding to the flanking sequence of these polymorphic repeats was used to amplify three different
marker haplotypes. The OPT marker was tightly linked to the Ms locus at a distance of 1.5 cM, but the analysis of the linkage relationship showed little linkage disequilibrium between
the marker and the Ms locus. Even so, these simple PCR markers are valuable tools for the marker-assisted selection of segregating individuals
in onion F1 hybrid breeding programs. 相似文献
72.
Jha P Mills A Hanson K Kumaranayake L Conteh L Kurowski C Nguyen SN Cruz VO Ranson K Vaz LM Yu S Morton O Sachs JD 《Science (New York, N.Y.)》2002,295(5562):2036-2039
We analyzed the technical basis for a major global program to reduce disease among the poor. Effective interventions exist against the few diseases which most account for excess mortality among the poor. Achieving high coverage of effective interventions requires a well-functioning health system, as well as overcoming a set of financial and nonfinancial constraints. The annual incremental cost would be between $40 billion and $52 billion by 2015 in 83 low-income and sub-Saharan African countries. Such a program is feasible and would avoid millions of child, maternal, and adult deaths annually in poor countries. 相似文献
73.
Shen WL Kwon Y Adegbola AA Luo J Chess A Montell C 《Science (New York, N.Y.)》2011,331(6022):1333-1336
Many animals, including the fruit fly, are sensitive to small differences in ambient temperature. The ability of Drosophila larvae to choose their ideal temperature (18°C) over other comfortable temperatures (19° to 24°C) depends on a thermosensory signaling pathway that includes a heterotrimeric guanine nucleotide-binding protein (G protein), a phospholipase C, and the transient receptor potential TRPA1 channel. We report that mutation of the gene (ninaE) encoding a classical G protein-coupled receptor (GPCR), Drosophila rhodopsin, eliminates thermotactic discrimination in the comfortable temperature range. This role for rhodopsin in thermotaxis toward 18°C was light-independent. Introduction of mouse melanopsin restored normal thermotactic behavior in ninaE mutant larvae. We propose that rhodopsins represent a class of evolutionarily conserved GPCRs that are required for initiating thermosensory signaling cascades. 相似文献
74.
75.
Changelian PS Flanagan ME Ball DJ Kent CR Magnuson KS Martin WH Rizzuti BJ Sawyer PS Perry BD Brissette WH McCurdy SP Kudlacz EM Conklyn MJ Elliott EA Koslov ER Fisher MB Strelevitz TJ Yoon K Whipple DA Sun J Munchhof MJ Doty JL Casavant JM Blumenkopf TA Hines M Brown MF Lillie BM Subramanyam C Shang-Poa C Milici AJ Beckius GE Moyer JD Su C Woodworth TG Gaweco AS Beals CR Littman BH Fisher DA Smith JF Zagouras P Magna HA Saltarelli MJ Johnson KS Nelms LF Des Etages SG Hayes LS Kawabata TT 《Science (New York, N.Y.)》2003,302(5646):875-878
Because of its requirement for signaling by multiple cytokines, Janus kinase 3 (JAK3) is an excellent target for clinical immunosuppression. We report the development of a specific, orally active inhibitor of JAK3, CP-690,550, that significantly prolonged survival in a murine model of heart transplantation and in cynomolgus monkeys receiving kidney transplants. CP-690,550 treatment was not associated with hypertension, hyperlipidemia, or lymphoproliferative disease. On the basis of these preclinical results, we believe JAK3 blockade by CP-690,550 has potential for therapeutically desirable immunosuppression in human organ transplantation and in other clinical settings. 相似文献
76.
Columnar defects generated by heavy-ion irradiation are promising structures for pinning magnetic flux lines and enhancing critical currents in superconductors with high transition temperatures. An approach that combines chemical etching and magnetic decoration was used to highlight simultaneously the distributions of columnar defects and magnetic flux lines in Bi(2)Sr(2)CaCu(2)O(8) superconductors. Analyses of images of the columnar defects and flux-line positions provide insight into flux-line pinning by elucidating (i) the occupancy of columnar defects by flux lines, (ii) the nature of topological defects in the flux-line lattice, and (iii) the translational and orientational order in this lattice. 相似文献
77.
Park HG Kim SH Kwon SH Ju YG Yang JK Baek JH Kim SB Lee YH 《Science (New York, N.Y.)》2004,305(5689):1444-1447
We report the experimental demonstration of an electrically driven, single-mode, low threshold current (approximately 260 microA) photonic band gap laser operating at room temperature. The electrical current pulse is injected through a sub-micrometer-sized semiconductor wire at the center of the mode with minimal degradation of the quality factor. The actual mode of interest operates in a nondegenerate monopole mode, as evidenced through the comparison of the measurement with the computation based on the actual fabricated structural parameters. As a small step toward a thresholdless laser or a single photon source, this wavelength-size photonic crystal laser may be of interest to photonic crystals, cavity quantum electrodynamics, and quantum information communities. 相似文献
78.
Zeolites are crystalline nanoporous aluminosilicates widely used in industry. In order for zeolites to find applications as innovative materials, they need to be organized into large two- and three-dimensional (2D and 3D) arrays. We report that uniformly aligned polyurethane films can serve as templates for the synthesis of uniformly aligned 2D and possibly 3D arrays of silicalite-1 crystals, in which the orientations of the crystals are controlled by the nature of the polymers. We propose that the supramolecularly organized organic-inorganic composites that consist of the hydrolyzed organic products and the seed crystals are responsible for this phenomenon. 相似文献
79.
80.
Carbohydrate digestion by α-glucosidase and subsequent glucose uptake at the brush border are critical for postprandial blood glucose control. Any specific inhibitors are useful as hyperglycemia modulating agents. In this study, it was postulated that an array of active components in mulberry leaf extract (MLE) may provide higher potency in inhibiting intestinal glucose absorption compared to the single component 1-deoxynojirimycin (DNJ), which is recognized as a promising inhibitor of intestinal glucose absorption. Both MLE and DNJ were active in inhibiting α-glucosidase. However, in Caco-2 cells, only MLE showed significant inhibition of 2-deoxyglucose uptake, whereas DNJ was ineffective. For glucose loading, co-administration of MLE resulted in potent inhibitions of glucose responses compared to those by DNJ in Sprague Dawley (SD) rats, but this was not found for maltose loading. These novel findings add evidence that the unabsorbed phytochemicals in MLE compete with glucose for intestinal glucose transporters, but DNJ itself does not. We also evaluated the timing of MLE consumption. By administering MLE for 30 min before glucose loading, the incremental area under the curve (IAUC) was significantly lowered in the rats, as compared to a simultaneously administered group. Similarly, cellular glucose uptake was significantly reduced in Caco-2 cells following pretreatment. 相似文献