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The authors evaluated whether completing a multi-item assessment of smoking craving (the Questionnaire of Smoking Urges [QSU]) promoted increases in smoking craving. A sample of 39 regular smokers was randomly assigned to 1 of 3 manipulations (each of 3 min duration): (a) complete the QSU–Brief (10 items), (b) complete a noncraving questionnaire that was structurally identical to the QSU–Brief (scale-based control), and (c) a time-based control. Participants responded to an oral question assessing their degree of craving immediately before and after the manipulations. Results indicated that the QSU did not promote increases in craving compared to the 2 control conditions. Despite continuing debate over the most appropriate self-report measure of craving, investigators who use the QSU–Brief can be reasonably sure that the scores that result are not biased due to reactivity effects. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Z.R. Abrams 《Carbon》2007,45(4):738-743
Interactions between atoms of bound single-walled carbon nanotubes are known to cause measurable distortion to the tube’s original circular cross-section. High-resolution transmission electron microscope investigation was used to directly image and verify these radial deformations. The data obtained provide direct measurements of the deformations due to the interactions between isolated pairs of nanotubes and is compared to previously reported experimental and simulation results.  相似文献   
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Presents an obituary for Brian Mullen. In a field that values empirical precedent and established paradigms, Brian Mullen's career was one of passion and originality. He was motivated by pure intellectual curiosity; the recognition he received for his pioneering work in archival methodology, meta-analysis, and group processes and relations was secondary. His contributions to the field of social psychology were unique and will be enduring. His 1985 book with Robert Rosenthal, BASIC Meta-Analysis: Procedures and Programs, is a classic. In 2006, he was identified as the 15th most cited scholar in social psychology textbooks. Brian died of cancer on May 4, 2006. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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When proteins are conjugated to fluorescent organic dyes, fluorescence emission of the dye molecules is usually decreased, sometimes up to 50-70%. This quenching phenomenon has been acknowledged for decades, but as yet, there are no simple, practical methods to control the fluorescence of dyes conjugated to proteins, especially for dyes conjugated to immunoglobulins. Here, we report that the addition of (2-hydroxypropyl)-β-cyclodextrin (HPβCD) to dye-antibody conjugates can increase fluorescence up to 2.5-fold in cell imaging and flow analysis. This method may be an effective way to increase the sensitivity of detection of fluorescent organic labels used in immunology, histochemistry, and cell biology.  相似文献   
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To determine whether counterregulation by interleukin (IL)-10 plays a role in the generation or maintenance of the antigen-specific hyporesponsiveness seen in asymptomatic microfilaremic (MF) patients, parasite antigen (PAg)- and nonparasite antigen (NPAg)-driven IL-10 production by peripheral blood mononuclear cells (PBMC) was studied in 10 MF patients and in ll patients with chronic lymphatic pathology (CP). PBMC from MF patients spontaneously secreted 10-fold more IL-10 than did PBMC from patients with CP. PAg also induced significantly more IL-10 production by PBMC from CP patients. There was a negative correlation between PAg driven IL-10 production by PBMC and PAg-specific T cell proliferation in the MF group. IL-10 secretion by plastic adherent cells from MF persons was higher in response to PAg than NPAg, whereas IL-6 and tumor necrosis factor-alpha secretion were equivalent for PAg and NPAg, suggesting that PAg preferentially induces IL-10 secretion in these cells. Thus, PAg-induced IL-10 likely plays an important role in down-regulating antigen-specific proliferative responses in MF patients.  相似文献   
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Aprikalim, a K+ ATP channel opener, is a potent vasodilator with demonstrated cardioprotective properties against ischemia/reperfusion injury. It is still unknown if K+ ATP channel openers exert their beneficial effects via interaction with oxygen-derived free radicals. Therefore, we investigated the cardioprotective effects of aprikalim against oxygen-derived free radicals. Isolated rabbit hearts were perfused at constant pressure (85 cm H2O) or constant flow (30-35 ml/min). Heart rate, left ventricular developed pressure (LVDP), and either coronary flow or coronary perfusion pressure (CPP) were monitored. Free radicals were produced by electrolysis of the perfusate (0.6 mA, direct current), and 10 microM aprikalim was infused before and after exposure to free radicals. In the constant perfusion pressure experiments, 10 min of exposure to free radicals resulted in a significant reduction of heart rate (137 to 129 beats/min), LVDP (112 to 91 mmHg) and coronary flow (37 to 29 ml/min); coronary flow was more markedly impaired than contractile function. Acetylcholine-induced coronary dilation was also significantly attenuated in the presence of free radicals. After 30 min of recovery, both coronary flow and LVDP were still significantly decreased while acetylcholine-induced coronary dilation had fully recuperated. Aprikalim completely abated the coronary and cardiac depressant actions of free radicals. Constant flow experiments indicated that exposure to free radicals increased CPP (+40%, p < 0.05), an effect totally suppressed by aprikalim. These results demonstrate that aprikalim reverses the cardiodepressant actions of free radicals. The cardioprotection it afforded involves both contractile function and the coronary vasculature. Acetylcholine-induced coronary dilation was blunted by free radicals, an indication of complex interactions at the coronary endothelial level.  相似文献   
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