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81.
Three experiments with 273 college students were conducted to reconcile the apparent contradiction between the well-established finding that initial impressions are resistant to incongruent (ICG) information and the finding that information ICG with an impression is particularly likely to be recalled. Using a procedure similar to that of R. Hastie and P. A. Kumar (1979), a situational or dispositional attribution was provided for a target item, which was either congruent (CG) or ICG with an initial impression. The ICG item was more likely than the CG item to be recalled only when attributed to dispositional causes (Exp I). The congruence of the target had greater impact on impressions when attributed to dispositional causes, particularly when Ss were given little other information about the target (Exps I and II). Exp III revealed that Ss preferred situational attributions for ICG items and dispositional attributions for CG. The authors conclude that Hastie and Kumar's findings may be limited to conditions in which situational attributions for TCG information are not provided. Possible mediators of the effects of causal attributions on recall, and the relation between recall and impressions are discussed. (29 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
A technique for examining heterogeneous copolymers with the phase microscope is described. This method is based on the use of a mounting medium that displays selective solubility toward the constituent materials, thereby masking one or more phases in order to provide suitable phase contrast and isolation of the constituent to be examined. 相似文献
83.
Fourteen antirheumatoid drugs were tested for their effects on the in vitro hyaluronidase activity of normal human serum. Four drugs produced significant changes in enzyme activity. Different results were obtained with ovine testicular hyaluronidase when diluted with either saline or inactivated human serum. No increase in serum hyaluronidase activity was found in patients with rheumatoid arthritis. There was no evidence for the existence of tissue specific isoenzymes of hyaluronidase in the serum of either normal subjects or patients with rheumatoid arthritis. 相似文献
84.
85.
Organic marker compounds (biomarkers) can be used to identify the sources of waterborne pollutants. This paper examines sterols and other alcohols in overland flow from pasture-based grazing systems, possible agricultural source materials and water extracts of these source materials as a preliminary step to developing chemical profiles that can be used for tracing pollutants. The biomarkers were quantified using gas chromatography and gas chromatography-mass spectrometry techniques. Analyses of plant material show that some pasture species contain unique compounds, enabling their identification. For example, Arctotheca calendula (capeweed) contains an as yet unidentified compound (Arctotheca m/z 163). Other pasture species that do not contain unique compounds do contain unique ratios of phytol, hexacosanol, octacosanol and 24-ethylcholesterol, enabling their identification. Analyses of faecal samples show that the ratios of sterols to stanols enable faeces to be distinguished from the pasture species, e.g. the ratio of 24-ethylcholesterol to 24-ethylcoprostanol was <1, generally <0.25 for faeces, while for most pasture species this ratio was >4. Using this ratio, qualitative apportioning of the sources of pollutants in overland flow to vegetation or faeces could be performed, but only in extreme cases (i.e. when the ratio <1 or >4). Decaying organic matter and surface soil appear to contain a composite of plant and faecal sterols. Sterols, being sparingly soluble in water and surface active, were not expected to be present in overland flow samples. Surprisingly, cholesterol and 24-ethylcoprostanol were found in both the particulate and filtrate fractions of most overland flow and water extracts of most source materials. Using the ratios of sterols to stanols, particulate organic material in water could be traced back to its broader source, i.e. vegetation or faeces. 相似文献
86.
Marion Maclean Davis Hannah B. Hetzer 《Journal of research of the National Institute of Standards and Technology》1961,(3):209-213
This paper reports values of ΔF25, ΔH, and ΔS25 for the association of diphenylguanidine with the isomeric monochlorobenzoic acids and the isomeric toluic acids in benzene from spectrophotometric measurements at 25 and 30 °C, using bromophthalein magenta E (3′, 5′, 3″, 5″-tetrabromophenolphthalein ethyl ester) as the indicator. The results are compared with available data for other donor-acceptor associations in aprotic solvents which include the monomer-dimer equilibrium of benzoic acids, the association of tertiary amines with iodine, and the association of certain oxygen bases with phenols. The comparisons indicate that the value of the ratio ΔH/298ΔS is approximately constant in the following associations in aprotic solvents: (1) Association of phenolic or carboxylic acids with nitrogenous bases to form hydrogen bonded ion-pairs; (2) hydrogen bonding of weakly acidic phenols to nitrogenous bases; (3) association of tertiary amines with iodine. A somewhat smaller value for this ratio seems to apply to most associations of phenols with oxygen bases. Possible applications of these findings include estimation of other thermodynamic constants when one of the constants ΔF, ΔH, or ΔS is known, and clarification of the relative importance of ionic and covalent contributions in hydrogen bond formation. 相似文献
87.
Suggests that, in his retrospective review of malpractice claims against psychologists, R. H. Wright (see record 1982-22006-001) infers beyond the limits of the data he reports. Specifically, he suggests that, because there were so few complaints of sexual misconduct, stories of sex between psychologist and patient are substantially overstated. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
88.
Sreepradha Eswaran Anshu Babbar Hannah K. Drescher Thomas C. A. Hitch Thomas Clavel Moritz Muschaweck Thomas Ritz Daniela C. Kroy Christian Trautwein Norbert Wagner Angela Schippers 《International journal of molecular sciences》2021,22(14)
(1) Background: Non-alcoholic fatty liver disease (NAFLD) is a growing global health problem. NAFLD progression involves a complex interplay of imbalanced inflammatory cell populations and inflammatory signals such as reactive oxygen species and cytokines. These signals can derive from the liver itself but also from adipose tissue or be mediated via changes in the gut microbiome. We analyzed the effects of a simultaneous migration blockade caused by L-selectin-deficiency and an enhancement of the anti-oxidative stress response triggered by hepatocytic Kelch-like ECH-associated protein 1 (Keap1) deletion on NAFLD progression. (2) Methods: L-selectin-deficient mice (Lsel−/−Keap1flx/flx) and littermates with selective hepatic Keap1 deletion (Lsel−/−Keap1Δhepa) were compared in a 24-week Western-style diet (WD) model. (3) Results: Lsel−/−Keap1Δhepa mice exhibited increased expression of erythroid 2-related factor 2 (Nrf2) target genes in the liver, decreased body weight, reduced epidydimal white adipose tissue with decreased immune cell frequencies, and improved glucose response when compared to their Lsel−/−Keap1flx/flx littermates. Although WD feeding caused drastic changes in fecal microbiota profiles with decreased microbial diversity, no genotype-dependent shifts were observed. (4) Conclusions: Upregulation of the anti-oxidative stress response improves metabolic changes in L-selectin-deficient mice but does not prevent NAFLD progression and shifts in the gut microbiota. 相似文献
89.
Emily R. Featherston Hannah R. Rose Molly J. McBride Ellison M. Taylor Prof. Amie K. Boal Prof. Joseph A. Cotruvo Jr. 《Chembiochem : a European journal of chemical biology》2019,20(18):2360-2372
Lanthanide (Ln)-dependent methanol dehydrogenases (MDHs) have recently been shown to be widespread in methylotrophic bacteria. Along with the core MDH protein, XoxF, these systems contain two other proteins, XoxG (a c-type cytochrome) and XoxJ (a periplasmic binding protein of unknown function), about which little is known. In this work, we have biochemically and structurally characterized these proteins from the methyltroph Methylobacterium extorquens AM1. In contrast to results obtained in an artificial assay system, assays of XoxFs metallated with LaIII, CeIII, and NdIII using their physiological electron acceptor, XoxG, display Ln-independent activities, but the Km for XoxG markedly increases from La to Nd. This result suggests that XoxG′s redox properties are tuned specifically for lighter Lns in XoxF, an interpretation supported by the unusually low reduction potential of XoxG (+172 mV). The X-ray crystal structure of XoxG provides a structural basis for this reduction potential and insight into the XoxG–XoxF interaction. Finally, the X-ray crystal structure of XoxJ reveals a large hydrophobic cleft and suggests a role in the activation of XoxF. These studies enrich our understanding of the underlying chemical principles that enable the activity of XoxF with multiple lanthanides in vitro and in vivo. 相似文献
90.
Dr. Elizabeth A. Love Afrah Sattikar Dr. Hannah Cook Kevin Gillen Dr. Jonathan M. Large Dr. Seema Patel Dr. David Matthews Dr. Andy Merritt 《Chembiochem : a European journal of chemical biology》2019,20(6):754-758
Antibody–drug conjugates (ADCs) are a growing class of therapeutics that harness the specificity of antibodies and the cell-killing potency of small-molecule drugs. Beyond cytotoxics, there are few examples of the application of an ADC approach to difficult drug discovery targets. Here, we present the initial development of a non-internalising ADC, with a view to selectively inhibiting an extracellular protein. Employing the wellinvestigated matrix metalloproteinase-9 (MMP-9) as our model, we adapted a broad-spectrum, nonselective MMP inhibitor for conjugation and linked this to a MMP-9-targeting antibody. The resulting ADC fully inhibits MMP-9, and ELISA results suggest antibody targeting can direct a nonselective inhibitor. 相似文献