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991.
The aim of this study was to investigate the effect of Asphodeline lutea (L.) Rchb. dry root extract (ALE) administered alone and against carbon tetrachloride (CCl4)-induced liver injury in vitro/in vivo. The dried roots of A. lutea were extracted with 70% ethanol and was characterized with HPLC-UV. Hepatoprotective potential was investigated by in vivo/in vitro assays in Wistar rats as well as antioxidant properties. At concentrations ranging from 10 to 200 μg/mL of ALE significant cytotoxic effects on isolated hepatocytes were found. ALE showed some toxicity in Wistar rats discerned by increased ALT (Alanine transaminase), ALP (Alkaline phosphatase) activities and MDA (malondialdehyde) quantity, decreased GSH (reduced glutathione) levels without affecting the activity of the antioxidant enzymes (GPx (Gluthatione peroxidase), GR (Glutathione reductase) and GST (Glutathione-S-transferase activity)). The antioxidant and hepatoprotective potential of ALE was also observed in vitro/in vivo against CCl4-induced liver injury, where ALE normalizes all the examined parameters perturbated by CCl4 administration. In addition, ALE preserved the decreased cytochrome P450 level and EMND (Ethylmorphine-N-Demethylase) activity without affecting AH (Aniline 4-Hydroxylase) activity. ALE is rich in anthraquinones, naphthalenes and caffeic acid. The pro-oxidant effects of ALE could be due to naphthalene and anthraquinone bioactivation pathways involving toxic metabolites. 相似文献
992.
993.
Organisation‐based self‐esteem mediates the effects of social support and job satisfaction on intention to stay in nurses
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994.
《Psycho-oncology》2018,27(4):1244-1250
995.
《Journal of adolescence》2014,37(8):1373-1377
Adolescence is a crucial phase of human life characterized by enhanced exposure and vulnerability to various stressful stimuli. The Adolescent Stress Questionnaire (ASQ) is a useful measure to evaluate possible sources of stressors affecting the adolescent equilibrium. The present study examines the scientific properties of the Greek version of ASQ to measure perceived stress among 250 Greek adolescents. The confirmatory factor analysis (CFA) results showed a good fit of the original structure of ASQ to the observed data in the Greek sample. A good internal reliability was also confirmed by high Cronbach's alpha values. In line with previous research, girls reported more stress than boys. Overall, the Greek ASQ is a valid and reliable instrument for evaluating adolescent stress. 相似文献
996.
Monica K. Miller Brian H. Bornstein Grant Shulman 《Psychiatry, Psychology and Law》2013,20(4):602-618
Because judges experience a myriad of occupational stressors, they are at risk of experiencing secondary trauma, burnout, negative mental/physical health, poor job performance and low job satisfaction. These experiences might not be uniform, however, as gender and social support might mitigate such stress-related outcomes. Judges from two states in the United States completed a variety of stress and subjective performance measures. Social support was related to less perceived stress, less burnout, and more job satisfaction, but only for males. This suggests that males and females might receive qualitatively different types of social support. Different types of social support could differ in their ability to buffer judges from these stress-related outcomes. Further, among judges with high social support, females scored higher than males on subjective job performance; the opposite pattern occurred for judges with low social support. Thus, a lack of social support appears to have a negative effect on performance self-appraisals but only for females. Results have implications for the psychological study of stress and for programs designed to reduce judges’ stress. 相似文献
997.
目的:探讨音乐与视听联合对人工流产病人心理应激的影响。方法:采用随机对照研究方法将150例人工流产病人随机分成3组,每组50例,①音乐组手术时戴耳机听音乐;②视听联合分散组手术时看DVD并戴耳机听碟片里播放的声音;③对照组手术时不听音乐也不看DVD。比较3组患者间的焦虑水平和人工流产综合征的发生情况。结果:音乐组手术后焦虑水平显著低于视听联合组和对照组(P〈0.05),视听联合组低于对照组,但差异无统计学意义(P〉0.05);人工流产综合征发生率:音乐组和视听联合组明显低于对照组(P〈0.01)。结论:音乐与视听联合能降低人工流产病人焦虑水平,减轻病人应激反应,减少手术并发症发生。 相似文献
998.
《Early child development and care》2012,182(5):449-460
The current study examined the relationship between Korean mothers’ parenting stress and parental intelligence, and child behavior problems as well as the mediation effects of parental intelligence, which tested the association between parenting stress and child behavior problems. A sample of 436 typically developing children and their mothers participated and were assessed by the Parenting Stress Index—Short Form, the Parental Intelligence Scale and the K‐Child Behavior Check List. Results indicated that parenting stress, parental intelligence and child behavior problems were related; especially, parenting stress significantly predicted child behavior problems. Despite its substantive relationship, parental intelligence did not appear to mediate this relationship. 相似文献
999.
Polybrominated diphenyl ethers (PBDEs) are widely used flame retardant compounds. Brominated diphenyl ether (BDE)-47 is one of the most prevalent PBDE congeners found in human breast milk, serum and placenta. Despite the presence of PBDEs in human placenta, effects of PBDEs on placental cell function are poorly understood. The present study investigated BDE-47-induced reactive oxygen species (ROS) formation and its role in BDE-47-stimulated proinflammatory cytokine release in a first trimester human extravillous trophoblast cell line, HTR-8/SVneo. Exposure of HTR-8/SVneo cells for 4 h to 20 μM BDE-47 increased ROS generation 1.7 fold as measured by the dichlorofluorescein (DCF) assay. Likewise, superoxide anion production increased approximately 5 fold at 10 and 15 μM and 9 fold at 20 μM BDE-47 with a 1-h exposure, as measured by cytochrome c reduction. BDE-47 (10, 15 and 20 μM) decreased the mitochondrial membrane potential by 47–64.5% at 4, 8 and 24 h as assessed with the fluorescent probe Rh123. Treatment with 15 and 20 μM BDE-47 stimulated cellular release and mRNA expression of IL-6 and IL-8 after 12 and 24-h exposures: the greatest increases were a 35-fold increased mRNA expression at 12 h and a 12-fold increased protein concentration at 24 h for IL-6. Antioxidant treatments (deferoxamine mesylate, (±)α-tocopherol, or tempol) suppressed BDE-47-stimulated IL-6 release by 54.1%, 56.3% and 37.7%, respectively, implicating a role for ROS in the regulation of inflammatory pathways in HTR-8/SVneo cells. Solvent (DMSO) controls exhibited statistically significantly decreased responses compared with non-treated controls for IL-6 release and IL-8 mRNA expression, but these responses were not consistent across experiments and times. Nonetheless, it is possible that DMSO (used to dissolve BDE-47) may have attenuated the stimulatory actions of BDE-47 on cytokine responses. Because abnormal activation of proinflammatory responses can disrupt trophoblast functions necessary for placental development and successful pregnancy, further investigation is warranted of the impact of ROS and BDE-47 on trophoblast cytokine responses. 相似文献
1000.
AbstractBackground: High-density lipoprotein (HDL) particles exert many beneficial actions that may help protect against cardiovascular disease. However, recent work has demonstrated that HDL can be oxidized and glycated under certain circumstances and may become pro-atherogenic. The present study investigated the impact of oxidized high-density lipoprotein (ox-HDL) and glycated apolipoprotein A-I (gly-ApoA-I) in patients presenting with ST-elevation myocardial infarction (STEMI).Methods: We assessed 55 consecutive patients with STEMI. Patients were divided into: (1) a stress hyperglycaemia (SH) and a no SH group; and (2) a high thrombus burden (HTB) group and a low thrombus burden (LTB) group. Meanwhile, 48 healthy volunteers were recruited as controls. Plasma ox-HDL and gly-ApoA-I concentrations were measured on admission and 7?days after admission.Results: Higher concentrations of ox-HDL and gly-ApoA-I were found in the STEMI group than in the control group on admission and at d7. Further subgroup analysis showed that ox-HDL and gly-ApoA-I were higher in the SH group than in the no SH group at both time points; the HTB group had higher ox-HDL and ox-HDL/HDL-C levels than the LTB group on admission and at d7. However, gly-ApoA-I and the relative intensity of ApoA-I glycation showed no significant differences between the HTB and LTB groups.Conclusions: The present data indicate that: (1) SH is associated with increased plasma concentrations of ox-HDL and gly-ApoA-I and therefore aggressive treatment is recommended; and (2) that ox-HDL and ox-HDL/HDL-C were higher in the HTB group and may be used to quantify thrombus burden. 相似文献