This paper attempts to make a contrastive cross-cultural study of a special speech act— “disagreement.” Participants are 35 American undergraduates and 42 Chinese undergraduates respectively with the data eliciting technique—DCT (discourse completion test). Findings show that Chinese undergraduates tend to use different politeness strategies according to different social distance and social power while American undergraduates prefer to use positive politeness strategy most followed by negative politeness strategy, regardless of social distance and social power. The results of the study reveal cultural differences between the U.S. and China that lead to the distribution of diverse politeness strategies and also offer insights into what Chinese EFL learners are struggling with during their development of interlanguage pragmatic competence.
It is accepted that inflammation plays a critical role in the development of atherosclerosis; the pathogenesis is not clear. B-cell-produced interleukin (IL) 10 is an immune regulatory cytokine that can inhibit immune inflammation. This study tests a hypothesis that a psychological stress hormone, cortisol, suppresses IL-10 expression in peripheral B cells of patients with atherosclerosis. Peripheral blood samples were collected from patients with coronary artery atherosclerosis. B cells were isolated from the blood samples to be analyzed for the expression of IL-10 and micro RNA (miR) 98 by real-time polymerase chain reaction. We observed that the frequency of IL-10 B cell was less in patients with atherosclerosis than healthy controls. The serum cortisol levels were higher in the patients than that in healthy controls. Peripheral B-cell frequency was negatively correlated with the serum cortisol levels. Exposure of B cells to cortisol increased the expression of miR-98 in B cells. Cortisol also inhibited the expression of IL-10 in B cells, in which miR-98 played a critical role. Treating B cells from atherosclerosis patients with anti-miR-98 liposomes reversed the ability of expression of IL-10 in the cells. The expression of IL-10 is suppressed in peripheral B cells, which can be up regulated by anti-miR-98 liposomes.
The effect of polyvinylpyrrolidone (PVP) as glycyrrhetic acid (GA) solid dispersions carrier at different molecular weights on the dissolution behavior and physicochemical properties was investigated. PVP-GA-SDs prepared with all four molecular weight PVPs displayed good enhancement of dissolution rate and equilibrium solubility compared with pure drug and corresponding physical mixtures. The results showed that the enhancement effect of molecular weight on dissolution rate and equilibrium solubility follows
PVP
K
30
>
PVP
K
60
>
PVP
K
17
>
PVP
K
15
. In addition, the dissolution rate and solubility of the SDs with a carrier-drug ratio of 8 : 1 were better than the samples of 4 : 1. The DSC and XRD patterns showed that the crystallization of GA in SDs prepared by PVP K30 and PVP K60 was significantly inhibited, and both were transformed to amorphous. Based on FTIR and Raman detection, a hydrogen-bond between PVP and drug molecules is formed. SEM results showed that there were no significant differences in the appearance of SDs prepared with four PVPs, and no crystalline morphology of GA was seen. In conclusion, the findings of this study demonstrated that the dissolution performance of the PVP-GA-SDs prepared by the solvent method is related to the molecular weight of PVP, and the change in the molecular weight of PVP does not cause a monotonic change in dissolution of GA. The samples with PVP K30 as the carrier have the best dissolution performance.
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