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排序方式: 共有460条查询结果,搜索用时 15 毫秒
1.
Daniela Frasca Maria Romero Alain Diaz Denisse Garcia Seth Thaller Bonnie B. Blomberg 《International journal of molecular sciences》2021,22(4)
Senescent cells accumulate in the adipose tissue (AT) of individuals with obesity and secrete multiple factors that constitute the senescence-associated secretory phenotype (SASP). This paper aimed at the identification of B cells with a SASP phenotype in the AT, as compared to the peripheral blood, of individuals with obesity. Our results show increased expression of SASP markers in AT versus blood B cells, a phenotype associated with a hyper-metabolic profile necessary to support the increased immune activation of AT-derived B cells as compared to blood-derived B cells. This hyper-metabolic profile is needed for the secretion of the pro-inflammatory mediators (cytokines, chemokines, micro-RNAs) that fuel local and systemic inflammation. 相似文献
2.
Haliza Abdul Aziz Noor Azeerah Abas Bonnie Tay Yen Ping Zainab Idris 《Journal of surfactants and detergents》2020,23(2):251-262
The technology for transesterification reactions between methyl esters and alcohols is well established by using classical homogeneous alkaline catalysts, which provide high conversion of methyl esters to specialty or nonindigenous esters. However, in certain products where the purity of the esters is of concern, the removal of homogeneous catalysts after the completion of the reaction is a challenge in terms of production cost and water footprint. Therefore, a study to investigate the potential of heterogeneous catalysts was conducted on reactions between methyl palmitate and triethanolamine. The degree of basicity and active surface area of calcium oxide (CaO), zinc oxide (ZnO), and magnesium oxide (MgO) were first characterized by using temperature-programmed desorption (TPD-CO2) and Brunauere–Emmett–Teller (BET), respectively. Among the metal oxides investigated, the CaO catalyst showed the best catalytic activity toward the transesterification process as it gave the highest conversion of methyl palmitate and yielded fatty esteramine compositions similar to the conventional homogeneous catalyst. The optimum transesterification condition by using the CaO catalyst utilized a lower vacuum system of approximately 200 mbar, which could minimize a considerable amount of energy consumption. Furthermore, low CaO dosage of 0.1% was able to give a conversion of 94.5% methyl ester and formed esteramine at 170 °C for 2 h. Therefore, the production of esterquats from esteramine may become more economically feasible through the methyl ester route by using the CaO catalyst, which can be recycled three times. 相似文献
3.
Hitsman Brian; Borrelli Belinda; McChargue Dennis E.; Spring Bonnie; Niaura Raymond 《Canadian Metallurgical Quarterly》2003,71(4):657
The authors conducted a meta-analysis of published studies to (a) evaluate the premise that a history of major depression is associated with failure to quit smoking and (b) identify factors that moderate the relationship between history of depression and cessation outcome. Fifteen studies met the selection requirements and were coded for various study methodology and treatment characteristics. DSTAT was used to calculate individual study effect sizes, determine the mean effect size across studies. and test for moderator effects. No differences in either short-term (≤ 3 months) or long-term abstinence rates (≥ 6 months) were observed between smokers positive versus negative for history of depression. Lifetime history of major depression does not appear to be an independent risk factor for cessation failure in smoking cessation treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
4.
Tokar David M.; Withrow Jason R.; Hall Rosalie J.; Moradi Bonnie 《Canadian Metallurgical Quarterly》2003,50(1):3
Structural equation modeling was used to test theoretically based models in which psychological separation and attachment security variables were related to career indecision and those relations were mediated through vocational self-concept crystallization. In contrast to previous studies, which have found either weak or no support for a relation between separation or attachment security variables and career indecision, results based on a sample of 350 college students indicated that some components of separation and attachment security did relate to career indecision in a theoretically supportable direction. Results also revealed that regardless of whether global or component career indecision measures were used, separation and attachment security effects on indecision were at least partially mediated through vocational self-concept crystallization. The strongest mediated relations were observed for the effects of attachment anxiety and maternal separation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Rat hepatocytes in monolayer culture were utilized to determine if the decrease in glucose-6-phosphate dehydrogenase (G6PD)
activity resulting from the ingestion of fat can be mimicked by the addition of fatty acids to a chemically, hormonally defined
medium. G6PD activity in cultured hepatocytes was induced several-fold by insulin. Dexamethasone or T3 did not amplify the
insulin induction of G6PD. Glucose alone increased G6PD activity in cultured hepatocytes from fasted donors by nearly 500%.
Insulin in combination with glucose induced G6PD an additional two-fold. The increase in G6PD activity caused by glucose was
greater in hepatocytes isolated from 72 hr-fasted rats as compared to fed donor rats. Such a response was reminiscent of the
“overshoot” phenomenon in which G6PD activity is induced well above the normal level by fasting-refeeding rats a high glucose
diet. Addition of linoleate to the medium resulted in a significant suppression of insulin’s ability to induce G6PD, but linoleate
had no effect on the induction of G6PD activity by glucose alone. A shift to the right in the insulin-response curve for the
induction of G6PD also was detected for the induction of malic enzyme and acetyl-CoA carboxylase. Arachidonate (0.25 mM) was
a significantly more effective inhibitor of the insulin action than linoleate was. Apparently rat hepatocytes in monolayer
culture can be utilized as a model to investigate the molecular mechanism by which fatty acids inhibit the production of lipogenic
enzymes. In part, this mechanism of fatty acid inhibition involves desensitization of hepatocytes to the lipogenic action
of insulin. 相似文献
8.
Chlorpyrifos is a Malaysian Pesticide Board-approved organophosphate insecticide, which may become concentrated during fractionation. The objective of this project was to develop and validate a method to detect and quantify chlorpyrifos in food-grade fatty acids ingredients, e.g. caprylic-capric acid mixture and oleic acid (OLA) used to synthesize triacylglyceride based food additives and in the cosmetic industry. A selective ion monitoring gas chromatography–mass spectrometry method with a matrix-matched calibration curve calibration was selected. The method involved the direct injection of chlorpyrifos spiked into the fatty acids matrix. The percentage recoveries at spiking levels of 0.5, 0.75, 2.5, and 4.0 μg g−1 of chlorpyrifos in OLA and caprylic-capric acid ranged from 85.7%–101.1% to 97.2%–112%, respectively, with a relative standard deviation of within 11%. The intra-day and inter-day precision were deemed acceptable as indicated by an relative SD value of within 10%. A good linear relationship with a coefficient of correlation >0.99 for the matrix-matched calibration was achieved between 0.5 and 5 μg g−1. The limit of detection and limit of quantification corresponded to 0.5 μg g−1 for OLA and 0.55 μg g−1 for caprylic-capric acid. 相似文献
9.
Jimmy Lin G. Craig Murray Bonnie J. Dorr Jan Hajič Pavel Pecina 《Language Resources and Evaluation》2009,43(1):27-40
Thesauri and controlled vocabularies facilitate access to digital collections by explicitly representing the underlying principles
of organization. Translation of such resources into multiple languages is an important component for providing multilingual
access. However, the specificity of vocabulary terms in most thesauri precludes fully-automatic translation using general-domain
lexical resources. In this paper, we present an efficient process for leveraging human translations to construct domain-specific
lexical resources. This process is illustrated on a thesaurus of 56,000 concepts used to catalog a large archive of oral histories.
We elicited human translations on a small subset of concepts, induced a probabilistic phrase dictionary from these translations,
and used the resulting resource to automatically translate the rest of the thesaurus. Two separate evaluations demonstrate
the acceptability of the automatic translations and the cost-effectiveness of our approach.
相似文献
Jimmy LinEmail: |
10.
Hendrik Voigt Aaron Rigoni Evgeniy Boltynjuk Mohammed Reda Chellali Bonnie Tyler Harald Rösner Sergiy Divinski Horst Hahn Gerhard Wilde 《Advanced functional materials》2023,33(44):2302386
Comprehensive analyses of the atomic structure using advanced analytical transmission electron microscopy-based methods combined with atom probe tomography confirm the presence of distinct glass–glass interfaces in a columnar Cu-Zr nanoglass synthesized by magnetron sputtering. These analyses provide first-time in-depth characterization of sputtered film nanoglasses and indicate that glass–glass interfaces indeed present an amorphous phase with reduced mass density as compared to the neighboring amorphous regions. Moreover, dedicated analyses of the diffusion kinetics by time-of-flight secondary ion mass spectroscopy (ToF SIMS) prove significantly enhanced diffusivity, suggesting fast transport along the low density glass–glass interfaces. The present results further indicate that sputter deposition is a feasible technique for reliable production of nanoglasses and that some of the concepts proposed for this new class of glassy materials are applicable. 相似文献