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排序方式: 共有617条查询结果,搜索用时 15 毫秒
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BACKGROUND & AIMS: The molecular mechanisms underlying pancreatitis are largely unknown. The goal of this study was to identify an early genetic event that correlated with pancreatitis. METHODS: Differential display of messenger RNAs (mRNAs) was conducted on normal pancreas vs. those of animals with secretagogue-induced pancreatitis. Northern blots from normal animals and animals with experimental acute pancreatitis were probed with cloned complementary DNAs for chemokines. Pancreatitis was induced with cerulein and by retrograde injection of bile salts. Immunocytochemistry was used to identify the source of chemokine expression. Pyrrolidine dithiocarbamate was tested for effects on chemokine expression and pancreatitis. RESULTS: A differentially amplified band was consistently observed early after cerulein hyperstimulation. This band was identified as a portion of the mob-1 gene, an alpha-chemokine. Northern analysis indicated that mRNAs for mob-1 and another chemokine, mcp-1, were induced after cerulein hyperstimulation in vivo. mob-1 mRNA was also induced by retrograde injection of bile salts and by cerulein in acinar cells in vitro. mob-1 protein was localized to exocrine cells in pancreata of diseased animals. Pyrrolidine dithiocarbamate inhibited both chemokine gene expression and early inflammatory characteristics of pancreatitis. CONCLUSIONS: Chemokines are induced in acinar cells by treatments that induce pancreatitis and may play an important role in the early stages of the disease. 相似文献
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J. Sieber D. Broton C. Fales S. Leigh B. MacDonald A. Marlow S. Nettles J. Yen 《Cement and Concrete Research》2002,32(12):1899-1906
The eight portland cements and two calcium aluminate cements in the Standard Reference Material (SRM) 1880 series are among the most popular SRMs in the catalog of the National Institute of Standards and Technology (NIST) Standard Reference Materials Program. Numerous laboratories rely on them for elemental analysis and qualification for ASTM C 114-00 Standard Test Methods for Chemical Analysis of Hydraulic Cement. NIST has collected new candidate materials from around the world and partnered with Construction Technology Laboratories (CTL) in their preparation and certification. This paper describes the procedures taken at NIST and CTL to prepare and test materials for certification including the homogeneity testing, the X-ray fluorescence methods and the statistical data analysis performed for value assignment. 相似文献
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Crocker Jennifer; Thompson Leigh L.; McGraw Kathleen M.; Ingerman Cindy 《Canadian Metallurgical Quarterly》1987,52(5):907
In two studies, we explored the effects of trait self-esteem and threats to the self-concept on evaluations of others. In Study 1, subjects high, moderate, and low in self-esteem received either success, failure, or no feedback on a test and later evaluated three pairs of targets: ingroups and outgroups based on a minimal intergroup manipulation, those who scored above average and those who scored below average on the test, and themselves and the average college student. Study 2 explored the effects of self-esteem and threat on ingroup favoritism in a real-world setting, campus sororities. Together, the results of these studies indicate that individuals high in self-esteem, but not those low in self-esteem, respond to threats to the self-concept by derogating outgroups relative to the ingroup when the group boundaries have evaluative implications. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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R Dawra A Saluja MM Lerch M Saluja C Logsdon M Steer 《Canadian Metallurgical Quarterly》1993,193(3):814-820
Pancreatic acinar cells possess both high low affinity receptors for cholecystokinin. The cholecystokinin analog caerulein, which exerts a trophic effect on the rat pancreas, acts as an agonist at both types of receptors. In contrast, the synthetic analog CCK-JMV-180, which also acts as an agonist at high affinity receptors, opposes the action of caerulein on the low affinity receptors. We report that infusion of either caerulein or CCK-JMV-180 into rats increases [3H]-thymidine incorporation into pancreatic DNA and causes the pancreatic weight as well as content of DNA, RNA, and protein to increase. CCK-JMV-180 also stimulates in-vitro incorporation of [3H]-thymidine into DNA of cultured rat acini. The finding that both caerulein and CCK-JMV-180 exert the same trophic effect on pancreatic acinar cells indicates that this effect is mediated via high affinity acinar cell cholecystokinin receptors. 相似文献
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Teri Linda; Truax Paula; Logsdon Rebecca; Uomoto Jay; Zarit Steven; Vitaliano Peter P. 《Canadian Metallurgical Quarterly》1992,7(4):622
The Revised Memory and Behavior Problems Checklist (RMBPC), a 24-item, caregiver-report measure of observable behavioral problems in dementia patients, provides 1 total score and 3 subscale scores for S problems (memory-related, depression, and disruptive behaviors) and parallel scores for caregiver reaction. Data were obtained from 201 geriatric Ss and their caregivers. Factor analysis confirmed 3 1st-order factors, consistent with subscales just named, and 1 general factor of behavioral disturbance. Overall scale reliability was good, with alphas of .84 for S behavior and .90 for caregiver reaction. Subscale alphas ranged from .67 to .89. Validity was confirmed through comparison of RMBPC scores with well-established indexes of depression, cognitive impairment, and caregiver burden. The RMBPC is recommended as a reliable and valid tool for the clinical and empirical assessment of behavior problems in dementia Ss. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Leigh M ClemowW.Roy Jackson 《Fuel》2002,81(7):959-961
Non-aqueous potentiometric titration using ethylenediamine as a solvent and sodium aminoethoxide as a titrant has been shown to be reliable for the estimation of total acidity only when the substrate is completely dissolved in the solvent. 相似文献
10.
Confined foaming of poly(ethylene-co-vinyl acetate-co-carbon monoxide) using carbon dioxide as a physical blowing agent in a mold with either permeable or impermeable boundaries has been explored as a strategy to control final foam dimensions and morphology. The results are discussed in terms of comparisons to free-foaming experiments conducted at the same pressure and temperature conditions following the same pressurization and depressurization paths. Foaming experiments were carried out at 30 and 40°C and 100, 200, and 300 bar followed by rapid depressurization of the foaming cell. Confined foaming led to smaller pores with more uniform distributions across the polymer cross-section. However, bulk foam densities of the foams generated under confinement were higher than those generated under the free-foaming mode. Surface characteristics and skin layer formation were altered by expansion against both the permeable and impermeable boundaries. Confined foaming promotes uniform pore distribution and overall dimensional uniformity and may impart surface texture but the trade-off is in the degree to which the bulk foam density can be lowered. 相似文献