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Covariances among Relatives in a Maize Variety (ZEA MAYS L.)   总被引:2,自引:2,他引:0       下载免费PDF全文
Chi RK  Eberhart SA  Penny LH 《Genetics》1969,63(2):511-520
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In a field study of 29 dairy farms, Pseudomonas aeruginosa was isolated more frequently (P = 0.05) from milking parlor udder wash water systems containing iodophor germicides than from those with no germicide. Most available iodine (AI2) concentrations were below the recommended level of 25 ppm (25 microgram/ml). Rubber and polyvinyl chloride hoses caused rapid decreases in the AI2 concentrations of 25 ppm iodophor solutions. AI2 dropped from 25 ppm to 6 ppm or less in 240 min for solutions contained in either polyvinyl chloride or rubber, compared with solutions in glass, which were unchanged in 240 min. Addition of inactivated iodophor solution to aqueous cultures resulted in significantly higher (P less than 0.05) numbers of P. aeruginosa at 10 and 24 h postinoculation. P. aeruginosa was grown in polyvinyl chloride tubing and exposed twice daily to 0, 10, or 25 ppm of AI2. None of the exposure concentrations eliminated the bacteria from the hoses, and bacterial numbers were not significantly different in hoses exposed to 0 and 10 ppm by the eighth treatment day. Bacteria taken from the water in these hoses were exposed to different concentrations of iodophor solution. Iodophor concentrations which will kill 50% of P. aeruginosa cultures previously exposed to 0, 10, and 25 ppm of AI2 were predicted to be 3.0, 11.8, and 20.8 ppm, respectively.  相似文献   
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Kang DE  Soriano S  Xia X  Eberhart CG  De Strooper B  Zheng H  Koo EH 《Cell》2002,110(6):751-762
The Alzheimer's disease-linked gene presenilin 1 (PS1) is required for intramembrane proteolysis of APP and Notch. In addition, recent observations strongly implicate PS1 as a negative regulator of the Wnt/beta-catenin signaling pathway, although the mechanism underlying this activity is unknown. Here, we show that presenilin functions as a scaffold that rapidly couples beta-catenin phosphorylation through two sequential kinase activities independent of the Wnt-regulated Axin/CK1alpha complex. Thus, presenilin deficiency results in increased beta-catenin stability in vitro and in vivo by disconnecting the stepwise phosphorylation of beta-catenin, both in the presence and absence of Wnt stimulation. These findings highlight an aspect of beta-catenin regulation outside of the canonical Wnt-regulated pathway and a function of presenilin separate from intramembrane proteolysis.  相似文献   
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This study aims at substituting the essential functions of photoreceptors in patients who are blind owing to untreatable forms of hereditary retinal degenerations. A microelectronic neuroprosthetic device, powered via transdermal inductive transmission, carrying 1500 independent microphotodiode-amplifier-electrode elements on a 9 mm2 chip, was subretinally implanted in nine blind patients. Light perception (8/9), light localization (7/9), motion detection (5/9, angular speed up to 35 deg s−1), grating acuity measurement (6/9, up to 3.3 cycles per degree) and visual acuity measurement with Landolt C-rings (2/9) up to Snellen visual acuity of 20/546 (corresponding to decimal 0.037 or corresponding to 1.43 logMAR (minimum angle of resolution)) were restored via the subretinal implant. Additionally, the identification, localization and discrimination of objects improved significantly (n = 8; p < 0.05 for each subtest) in repeated tests over a nine-month period. Three subjects were able to read letters spontaneously and one subject was able to read letters after training in an alternative-force choice test. Five subjects reported implant-mediated visual perceptions in daily life within a field of 15° of visual angle. Control tests were performed each time with the implant''s power source switched off. These data show that subretinal implants can restore visual functions that are useful for daily life.  相似文献   
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Anti-apoptotic Bcl-2 family proteins are important oncology therapeutic targets. To date, BH3 mimetics that abrogate anti-apoptotic activity have largely been directed at Bcl-2 and/or Bcl-xL. One observed mechanism of resistance to these inhibitors is increased Mcl-1 levels in cells exposed to such therapeutics. For this reason, and because Mcl-1 is important in the onset of lymphoid, myeloid, and other cancers, it has become a target of great interest. However, small molecule inhibitors displaying potency and selectivity for Mcl-1 are lacking. Identifying such compounds has been challenging due to difficulties in translating the target selectivity observed at the biochemical level to the cellular level. Herein we report the results of an HTS strategy coupled with directed hit optimization. Compounds identified have selective Mcl-1 inhibitory activity with greater than 100-fold reduced affinity for Bcl-xL. The selectivity of these compounds at the cellular level was validated using BH3 profiling, a novel personalized diagnostic approach. This assay provides an important functional biomarker that allows for the characterization of cells based upon their dependencies on various anti-apoptotic Bcl-2 proteins. We demonstrate that cells dependent on Mcl-1 or Bcl-2/Bcl-xL for survival are commensurately responsive to compounds that genuinely target those proteins. The identification of compound 9 with uniquely validated and selective Mcl-1 inhibitory activity provides a valuable tool to those studying the intrinsic apoptosis pathway and highlights an important approach in the development of a first-in-class cancer therapeutic.  相似文献   
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