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91.
Previous work has shown that abrupt visual onsets capture attention. Possible mechanisms for this phenomenon include (1) luminance-change detection system and (2) a mechanism that detects the appearance of new perceptual objects. Exps 1 and 2 revealed that attention is captured in visual search by the appearance of a new perceptual object even when the object is equiluminant with its background and thus exhibits no luminance change when it appears. Exp 3 showed that a highly salient luminance increment alone is not sufficient to capture attention. These findings suggest that attentional capture is mediated by a mechanism that detects the appearance of new perceptual objects. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
92.
Linehan Marsha M.; Comtois Katherine Anne; Brown Milton Z.; Heard Heidi L.; Wagner Amy 《Canadian Metallurgical Quarterly》2006,18(3):303
The authors describe the development of the Suicide Attempt Self-Injury Interview (SASII), an instrument designed to assess the factors involved in nonfatal suicide attempts and intentional self-injury. Using 4 cohorts of participants, authors generated SASII items and evaluated them with factor and content analyses and internal consistency statistics. The final measure was assessed for reliability and validity with collateral measures. The SASII assesses variables related to method, lethality and impulsivity of the act, likelihood of rescue, suicide intent or ambivalence and other motivations, consequences, and habitual self-injury. The SASII was found to have very good interrater reliability and adequate validity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
93.
Yannick Trguier Anne Bull-Maurer Philippe Roingeard 《International journal of molecular sciences》2022,23(7)
Apolipoprotein E (ApoE) is a multifunctional protein expressed in several tissues, including those of the liver. This lipoprotein component is responsible for maintaining lipid content homeostasis at the plasma and tissue levels by transporting lipids between the liver and peripheral tissues. The ability of ApoE to interact with host-cell surface receptors and its involvement in several cellular pathways raised questions about the hijacking of ApoE by hepatotropic viruses. Hepatitis C virus (HCV) was the first hepatitis virus reported to be dependent on ApoE for the completion of its lifecycle, with ApoE being part of the viral particle, mediating its entry into host cells and contributing to viral morphogenesis. Recent studies of the hepatitis B virus (HBV) lifecycle have revealed that this virus and its subviral envelope particles also incorporate ApoE. ApoE favors HBV entry and is crucial for the morphogenesis of infectious particles, through its interaction with HBV envelope glycoproteins. This review summarizes the data highlighting the crucial role of ApoE in the lifecycles of HBV and HCV and discusses its potential role in the lifecycle of other hepatotropic viruses. 相似文献
94.
Marina G. Yefimova Emile Br Anne Cantereau-Becq Annie-Claire Meunier-Balandre Bruno Merceron Agns Burel Karine Merienne Clia Ravel Frdric Becq Nicolas Bourmeyster 《International journal of molecular sciences》2021,22(23)
Visual deficit is one of the complications of Huntington disease (HD), a fatal neurological disorder caused by CAG trinucleotide expansions in the Huntingtin gene, leading to the production of mutant Huntingtin (mHTT) protein. Transgenic HD R6/1 mice expressing human HTT exon1 with 115 CAG repeats recapitulate major features of the human pathology and exhibit a degeneration of the retina. Our aim was to gain insight into the ultrastructure of the pathological HD R6/1 retina by electron microscopy (EM). We show that the HD R6/1 retina is enriched with unusual organelles myelinosomes, produced by retinal neurons and glia. Myelinosomes are present in all nuclear and plexiform layers, in the synaptic terminals of photoreceptors, in the processes of retinal neurons and glial cells, and in the subretinal space. In vitro study shows that myelinosomes secreted by human retinal glial Müller MIO-M1 cells transfected with EGFP-mHTT-exon1 carry EGFP-mHTT-exon1 protein, as revealed by immuno-EM and Western-blotting. Myelinosomes loaded with mHTT-exon1 are incorporated by naive neuronal/neuroblastoma SH-SY5Y cells. This results in the emergence of mHTT-exon1 in recipient cells. This process is blocked by membrane fusion inhibitor MDL 28170. Conclusion: Incorporation of myelinosomes carrying mHTT-exon1 in recipient cells may contribute to HD spreading in the retina. Exploring ocular fluids for myelinosome presence could bring an additional biomarker for HD diagnostics. 相似文献
95.
Anne Bagley Hardy Wendell E. Rhine H. Kent Bowen 《Journal of the American Ceramic Society》1993,76(1):97-104
A new method for forming spherical, submicrometer ceramic oxide particles by the hydrolysis of emulsified alkoxide droplets is reported. Emulsions are formed of alkoxide droplets dispersed in an inert, polar solvent. The alkoxide droplets are hydrolyzed to form oxide particles by adding water to the emulsion. It was shown that individual droplets acted as "microreactors" and controlled the powder size, shape, and composition. Both single-oxide and mixed-oxide powders were formed by this technique. 相似文献
96.
Louise M. Canfield Judy M. Hopkinson Anne F. Lima Gail S. Martin Kyoto Sugimoto Jeanne Burr Larry Clark Daniel L. McGee 《Lipids》1990,25(7):406-411
A quantitative method was developed for the assay of vitamin K in human colostrum and milk. The procedure combines preparative
and analytical chromatography on silica gel in a nitrogen atmosphere followed by reversed phase high performance liquid chromatography
(HPLC). Two HPLC steps were used: gradient separation with ultraviolet (UV) detection followed by isocratic separation detected
electrochemically. Due to co-migrating impurities, UV detection alone is insufficient for identification of vitamin K. Exogenous
vitamin K was shown to equilibrate with endogenous vitamin K in the samples. A statistical method was incorporated to control
for experimental variability. Vitamin K1 was analyzed in 16 pooled milk samples from 7 donors and in individual samples from 15 donors at 1 month post-partrum. Vitamin
K1 was present at 2.94±1.94 and 3.15±2.87 ng/mL in pools and in individuals, respectively. Menaquinones, the bacterial form
of the vitamin, were not detected. The significance of experimental variation to studies of vitamin K in individuals is discussed. 相似文献
97.
98.
Gruffat D De La Torre A Chardigny JM Durand D Loreau O Sébédio JL Bauchart D 《Lipids》2003,38(2):157-163
Hepatic metabolism of the two main isomers of CLA (9cis-11 trans, 10trans-12cisC18∶2) was compared to that of oleic acid (representative of the main plasma FA) in 16 rats by using the in vitro method of incubated liver slices. Liver tissue samples were incubated at 37°C for 17h under an atmosphere of 95% O2/5%CO2 in a medium supplemented with 0.75 mM of FA mixture (representative of circulating nonesterified FA) and with 55 μM [1-14C]9cis-11 trans C18∶2, [1-14C]10trans-12cis C18∶2, or [1-14C]oleate. The uptake of CLA by hepatocytes was similar for both isomers (9%) and was three times higher (P<0.01) than for oleate (2.6%). The rate of CLA isomer oxidation was two times higher (49 and 40% of incorporated amounts of
9cis-11 trans and 10trans-12 cis, respectively) than that of oleate (P<0.01). Total oxidation of oleate and CLA isomers into [14CO2] was low (2 to 7% of total oxidized FA) compared to the partial oxidation (93 to 98%) leading to the production of [14C] acid-soluble products. CLA isoemrs escaping from catabolism were both highly desaturated (26.7 and 26.8%) into conjugated
18∶3. Oleate and CLA isomers were mainly esterified into neutral lipids (30%). They were slowly secreted as parts of VLDL
particles (<0.4% of FA incorporated into cells), the extent of secretion of oleate and of 10trans-12 cis being 2.2-fold higher than that of 9cis-11 trans (P<0.02). In conclusion, this study clearly showed that both CLA isomers were highly catabolized by hepatocytes, reducing their
availability for peripheral tissues. Moreover, more than 25% of CLA escaping from catabolism was converted into conjugated
18∶3, the biological properties of which remain to be elucidated. 相似文献
99.
Top S Kaloun el B Vessières A Leclercq G Laïos I Ourevitch M Deuschel C McGlinchey MJ Jaouen G 《Chembiochem : a European journal of chemical biology》2003,4(8):754-761
The goal of our study was to potentiate the effects of the ((R,R)-trans-1,2-diaminocyclohexane)-platinum(II) fragment [(DACH)Pt], known for its cytotoxic properties, either with tamoxifen (Tam), the most widely used antiestrogen in the treatment of hormone-dependent breast cancers, or with its active metabolite hydroxytamoxifen (hydroxy-Tam). We coupled Tam or hydroxy-Tam derivatives bearing a malonato group at the para position of the beta aromatic ring with the (DACH)Pt fragment. The malonato-Tam and malonato-hydroxy-Tam compounds were prepared through McMurry coupling of the appropriate ketones. The presence of the malonate group resulted in a pronounced stereospecificity in the reaction, since malonato-Tam was obtained only as the Z isomer, while malonato-hydroxy-Tam was obtained as an 80/20 E/Z mixture. Attribution of the isomeric structures was achieved by 2D NMR spectroscopy. The platinum complexes (DACH)Pt-malonato-Tam and (DACH)Pt-malonato-hydroxy-Tam were then prepared by coupling the barium salts derived from the malonato-Tam and malonato-hydroxy-Tam with the nitrate derived from (DACH)PtCl(2). Study of the biochemical properties of these two platinum complexes showed that, while the hydroxy-Tam complex is satisfactorily recognized by the estrogen receptor (relative binding affinity, RBA=6.4 %), the Tam complex is less well recognized (RBA=0.5 %). The effects of these complexes on two hormone-dependent breast cancer cell lines (MCF7 and MVLN) were studied in vitro. Both complexes showed an antiproliferative effect on MCF7 cells, and an antiestrogenic effect on MVLN cells. The observed effects appear to be essentially antihormonal, since incorporation of the (DACH)Pt fragment into the tamoxifen skeleton did not cause an increase in the cytotoxicity of the complexes. 相似文献
100.
Mette B. Let Charlotte Jacobsen Edwin N. Frankel Anne S. Meyer 《European Journal of Lipid Science and Technology》2003,105(9):518-528
The oxidative deterioration of milk emulsions supplemented with 1.5 wt‐% fish oil was investigated by sensory evaluation and by determining the peroxide value and volatile oxidation products after cold storage. Two types of milk emulsions were produced, one with a highly unsaturated tuna oil (38 wt‐% of n‐3 fatty acids) and one with cod liver oil (26 wt‐% of n‐3 fatty acids). The effect of added calcium disodium ethylenediaminetetraacetate (EDTA) on oxidation was also investigated. Emulsions based on cod liver oil with a slightly elevated peroxide value (1.5 meq/kg) oxidised significantly faster than the tuna oil emulsions, having a lower initial peroxide value (0.1 meq/kg). In the tuna oil emulsions the fishy off‐flavour could not be detected throughout the storage period. Addition of 5—50 ppm EDTA significantly reduced the development of volatile oxidation products in the cod liver oil emulsions, indicating that metal chelation with EDTA could inhibit the decomposition of lipid hydroperoxides in these emulsions. This study showed that an oxidatively stable milk emulsion containing highly polyunsaturated tuna fish oil could be prepared without significant fishy off‐flavour development upon storage, provided that the initial peroxide value was sufficiently low. 相似文献