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101.
Rosenwald AG Rhodes MA Van Valkenburgh H Palanivel V Chapman G Boman A Zhang CJ Kahn RA 《Yeast (Chichester, England)》2002,19(12):1039-1056
To examine the functions of the Arf-like protein, Arl1p, in Saccharomyces cerevisiae, a null allele, arl1delta::HIS3, was constructed in two strains. In one background only, loss of ARL1 resulted in temperature-sensitive (ts) growth (suppressed on high-osmolarity media). Allelic variation at the SSD1 locus accounted for differences between strains. Strains lacking ARL1 exhibited several defects in membrane traffic. First, arl1delta strains secreted less protein as measured by TCA-precipitable radioactivity found in the media of [(35)S]-labelled cells. A portion of newly synthesized carboxypeptidase Y (CPY) was secreted rather than correctly targeted to the vacuole. Uptake of the fluid-phase marker, lucifer yellow, was reduced. All these phenotypes were exacerbated in an ssd1 background. The ts phenotype of the arl1deltassd1 strain was suppressed by YPT1, the yeast Rab1a homologue, suggesting that ARL1 and YPT1 have partially overlapping functions. These findings demonstrate that ARL1 encodes a regulator of membrane traffic. 相似文献
102.
Comparison of nine common coffee extraction methods: instrumental and sensory analysis 总被引:3,自引:0,他引:3
Alexia N. Gloess Barbara Schönbächler Babette Klopprogge Lucio D`Ambrosio Karin Chatelain Annette Bongartz André Strittmatter Markus Rast Chahan Yeretzian 《European Food Research and Technology》2013,236(4):607-627
The preparation of a cup of coffee may vary between countries, cultures and individuals. Here, an analysis of nine different extraction methods is presented regarding analytical and sensory aspects for four espressi and five lunghi. This comprised espresso and lungo from a semi-automatic coffee machine, espresso and lungo from a fully automatic coffee machine, espresso from a single-serve capsule system, mocha made with a percolator, lungo prepared with French Press extraction, filter coffee and lungo extracted with a Bayreuth coffee machine. Analytical measurements included headspace analysis with HS SPME GC/MS, acidity (pH), titratable acidity, content of fatty acids, total solids, refractive indices (expressed in °Brix), caffeine and chlorogenic acids content with HPLC. Sensory analysis included visual, aroma, flavor and textural attributes as well as aftersensation. The technical differences in the extraction methods led to a higher concentration of the respective quantities in the espressi than in the lunghi. Regarding the contents per cup of coffee, the lunghi generally had a higher content than the espressi. The extraction efficiency of the respective compounds was mainly driven by their solubility in water. A higher amount of water, as in the extraction of a lungo, generally led to higher extraction efficiency. Comparing analytical data with sensory profiles, the following positive correlations were found total solids ? texture/body, headspace intensity ? aroma intensity, concentrations of caffeine/chlorogenic acids ? bitterness and astringency. 相似文献
103.
Alan P. Jenkins Annette P. Bramley David J. Edwards David Dew-Hughes Chris R.M. Grovenor 《Journal of Superconductivity》1998,11(1):5-8
Linear microstrip resonators suffer from high peak current density inside the resonators which limit the power handling characteristics. To realise higher power filters for cellular applications it is possible to use two dimensional microstrip resonators (such as disks) to equalise the internal current distribution. We have designed and tested such microstrip resonators, fabricated from TBCCO 2212 thin films deposited by RF sputtering onto 10×10mm and 20×20mm LaAlO3, substrates. The Rs of such films has been measured at 24 GHz using a sapphire dielectric resonator and shown to be less than 500 scaled to 10 GHz and at 80K. Q values of 3-12 GHz disk resonators have demonstrated considerable improvements when compared to both linear HTS microstrip resonators and comparable copper disk resonators. Additionally, the power handling of such resonators has been shown to be superior to that of conventional linear resonators fabricated from similar material. 相似文献
104.
Lin Yang Regine Gradl Martin Dierolf Winfried Mller David Kutschke Annette Feuchtinger Lorenz Hehn Martin Donnelley Benedikt Günther Klaus Achterhold Axel Walch Tobias Stoeger Daniel Razansky Franz Pfeiffer Kaye S. Morgan Otmar Schmid 《Small (Weinheim an der Bergstrasse, Germany)》2019,15(49)
Targeted delivery of nanomedicine/nanoparticles (NM/NPs) to the site of disease (e.g., the tumor or lung injury) is of vital importance for improved therapeutic efficacy. Multimodal imaging platforms provide powerful tools for monitoring delivery and tissue distribution of drugs and NM/NPs. This study introduces a preclinical imaging platform combining X‐ray (two modes) and fluorescence imaging (three modes) techniques for time‐resolved in vivo and spatially resolved ex vivo visualization of mouse lungs during pulmonary NP delivery. Liquid mixtures of iodine (contrast agent for X‐ray) and/or (nano)particles (X‐ray absorbing and/or fluorescent) are delivered to different regions of the lung via intratracheal instillation, nasal aspiration, and ventilator‐assisted aerosol inhalation. It is demonstrated that in vivo propagation‐based phase‐contrast X‐ray imaging elucidates the dynamic process of pulmonary NP delivery, while ex vivo fluorescence imaging (e.g., tissue‐cleared light sheet fluorescence microscopy) reveals the quantitative 3D drug/particle distribution throughout the entire lung with cellular resolution. The novel and complementary information from this imaging platform unveils the dynamics and mechanisms of pulmonary NM/NP delivery and deposition for each of the delivery routes, which provides guidance on optimizing pulmonary delivery techniques and novel‐designed NM for targeting and efficacy. 相似文献
105.
Fricke Rolf Schreier Ellen Eckelt Reinhard Richter Manfred Trunschke Annette 《Topics in Catalysis》2004,30(1-4):193-198
Topics in Catalysis - The NO storage properties of MnO x /support materials (5–50 wt% MnO x loading) was experimentally investigated in the presence of O2 and H2O between 50 and... 相似文献
106.
107.
Stanton Annette L.; Danoff-Burg Sharon; Cameron Christine L.; Cameron Christine L.; Snider Pamela R.; Kirk Sarah B. 《Canadian Metallurgical Quarterly》1999,18(2):151
In a study designed to evaluate the divergence of social comparison activities under health threat, breast cancer patients (n?=?94) were assigned randomly to listen to an audiotaped interview in which the target's psychological adjustment and disease prognosis were manipulated to reflect good, poor, and unspecified psychological and physical health status. Results supported hypotheses regarding downward self-evaluative and upward affiliative comparison activity, as well as predictions regarding the influences of comparison dimension. With regard to desire for affiliation, participants demonstrated a greater desire for information and emotional support from the well-adjusted target than from the poorly adjusted target. Self-evaluation of adjustment and prognosis varied as a function of target characteristics, although a pervasive tendency toward downward comparison in self-evaluation also was noted. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
Annette Kaindl Wolfgang Lehner Peter Greil Deug Joong Kim 《Materials Science and Engineering: A》1999,260(1-2):101-107
Manufacturing, microstructure and properties of novel reaction bonded Mo2C materials derived from polymer/reactive filler mixtures were investigated. Mo powder was used as a filler to react with carbon bearing decomposition products of poly(methyl- and phenysiloxanes) during pyrolysis in nitrogen atmosphere. Microcrystalline composites with the filler reaction products Mo3C, Mo3Si, Mo5Si3 embedded in a silicon oxycarbide glass matrix could be formed with complex geometry owing to near net shape polymer/ceramic conversion. Depending on the precursor composition and pyrolysis conditions, ceramic hard materials with a density up to 97% theoretical density, a hardness of 10 GPa, a Young’s Modulus of 250 GPa, a fracture toughness of 5 MPam1/2 and a flexural strength of 330 MPa were obtained. 相似文献
109.
Clmentine Dillard Chlo Borde Ammara Mohammad Virginie Puchois Laurent Jourdren Annette K. Larsen Michle Sabbah Vincent Marchal Alexandre E. Escargueil Elodie Pramil 《International journal of molecular sciences》2021,22(21)
The purine nucleotide adenosine triphosphate (ATP) is known for its fundamental role in cellular bioenergetics. However, in the last decades, different works have described emerging functions for ATP, such as that of a danger signaling molecule acting in the extracellular space on both tumor and stromal compartments. Beside its role in immune cell signaling, several studies have shown that high concentrations of extracellular ATP can directly or indirectly act on cancer cells. Accordingly, it has been reported that purinergic receptors are widely expressed in tumor cells. However, their expression pattern is often associated with contradictory cellular outcomes. In this work, we first investigated gene expression profiles through “RNA-Sequencing” (RNA Seq) technology in four colorectal cancer (CRC) cell lines (HT29, LS513, LS174T, HCT116). Our results demonstrate that CRC cells mostly express the A2B, P2X4, P2Y1, P2Y2 and P2Y11 purinergic receptors. Among these, the P2Y1 and P2Y2 coding genes are markedly overexpressed in all CRC cells compared to the HCEC-1CT normal-like colonic cells. We then explored the cellular outcomes induced by extracellular ATP and adenosine. Our results show that in terms of cell death induction extracellular ATP is consistently more active than adenosine against CRC, while neither compound affected normal-like colonic cell survival. Intriguingly, while for the P2Y2 receptor pharmacological inhibition completely abolished the rise in cytoplasmic Ca2+ observed after ATP exposure in all CRC cell lines, Ca2+ mobilization only impacted the cellular outcome for HT29. In contrast, non-selective phosphodiesterase inhibition completely abolished the effects of extracellular ATP on CRC cells, suggesting that cAMP and/or cGMP levels might determine cellular outcome. Altogether, our study provides novel insights into the characterization of purinergic signaling in CRC. 相似文献
110.
Annette Hautli-Janisz 《Machine Translation》2015,29(3-4):285-289