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91.
Lambros Lazuras Angelos Rodafinos Georgios Matsiggos Alexander Stamatoulakis 《Social science & medicine (1982)》2009
The present study examined four potential roles of work-related negative affectivity on the associations between self-reported occupational stress and physical well-being among telecommunication employees in Greece. Participants (764, predominantly male) completed a battery of self-report measures on perceived occupational stress, negative affectivity, and illness symptoms. In line with previous research, negative affectivity exerted a nuisance effect, by inflating the association between reported stressors and illness symptoms, and significantly predicted illness symptoms, over and above the effects of stressors. In addition, negative affectivity influenced reported illness symptom indirectly, through the effects of stressors, and moderated the relationship between interpersonal conflict at work and illness symptoms. The findings suggest that negative affectivity can largely explain and influence in different ways the associations between self-reported stress and physical strain. It is recommended that future studies of occupational stress should control for the effects of negative affectivity, and that health professionals should be cautious of its effects when interpreting relationships between self-reported occupational stress and physical well-being. 相似文献
92.
恐惧应激对大鼠睾丸中Annexin5表达的影响 总被引:1,自引:0,他引:1
目的观察大鼠应激条件下睾丸组织中Annexin5表达的变化。方法建立SD大鼠的恐惧应激模型,分别取急性应激、急性对照、慢性应激、慢性对照SD大鼠睾丸,免疫组织化学和Western blotting分析Annexin5免疫定位和蛋白表达。结果急性应激组与对照组相比,免疫组化显示Annexin5都定位在间质细胞、支持细胞和成熟的精子头部,Western blotting分析发现Annexin5的表达降低了10.8%;慢性应激组与对照组相比,免疫组化结果显示Annexin5在精子头部的定位逐渐减少,应激1w和2w组,未见到Annexin5定位于精子头部,到了应激的3w和4w,发现Annexin5重新定位于精子的头部,而在间质细胞和支持细胞上的定位模式没有显著变化。Western blotting分析发现Annexin5的表达降低了17.4%。结论大鼠睾丸Annexin5参与了应激过程,急性应激条件下Annexin5表达降低。随着应激时间的延长,在慢性应激条件下,Annexin5的表达由减少之后而开始有缓慢增加。 相似文献
93.
Saara Tyry Raija Kalimo Markku rimaa Juhani Juntunen Markku Seuri Kimmo Rsnen 《Stress and health》2004,20(4):213-221
The aim of this study was to analyse the influence of gender and children on physicians' stress and burnout and to obtain information on the compromises physicians make between family and work. The study was based on a nationwide survey of 3313 Finnish physicians. The results showed that work was the commonest reason for stress for both male and female physicians. If physicians had children, combining work and family was the commonest reason for stress among the women, but work still remained the commonest reason for stress among the men. The female physicians had made compromises between family and work more often than the male physicians (limited the number of children, delayed having children, given up postgraduate or continuing medical education, worked part‐time because of family, and given up a job because of a spouse's need to move). The female physicians—with or without children—were more likely than the male physicians to experience severe or moderate exhaustion and less likely than the male physicians to experience cynicism as components of burnout. Among both genders of physicians, having children was associated with less cynicism and reduced personal accomplishment, but the children did not affect exhaustion. In conclusion, having children is associated with a lower level of some burnout symptoms. Additional studies are needed to explain the health effects of work–family balance for physicians. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
94.
Hagit Cohen Joseph Zohar Michael A Matar Zeev Kaplan Amir B Geva 《Neuropsychopharmacology》2005,58(8):640-650
BACKGROUND: Unsupervised fuzzy clustering (UFC) analysis is a mathematical technique that groups together objects in the multidimensional feature space according to a specified similarity measurement, thereby yielding clusters of similar data points that can be represented by a set of prototypes or centroids. METHODS: Since clinical studies of mental disorders distinguish between affected and unaffected individuals, we designed an inclusion/exclusion criteria (cutoff behavioral criteria [CBC]) approach for animal behavioral studies. The effect of classifying the study population into clearly affected versus clearly unaffected individuals according to behaviors on two behavioral paradigms was statistically significant. RESULTS: Here the raw data from previous studies were subjected to UFC algorithms as a means of objectively testing the validity of the concept of the CBC for our experimental model. The first UFC algorithm yielded two clearly discrete clusters, found to consist almost exclusively of the exposed animals in the one and unexposed animals in the other. The second algorithm yielded three clusters corresponding to animals designated as clearly affected, partially affected, and clearly unaffected. The algorithm for physiological data in addition to behavioral data failed to elicit discrete clusters. CONCLUSIONS: The UFC analysis yielded data that support the conceptual contention of the CBC and lends additional validity to our previous behavioral studies. 相似文献
95.
目的 :探讨氧化反应对糖尿病大鼠造影剂肾病发生的影响。方法 :建立SD大鼠糖尿病动物模型 ,8w后分 3组 :正常对照组 (SD组 )、糖尿病对照组 (DM组 )和糖尿病 +造影剂组 (CM组 )。其中CM组大鼠经尾静脉一次性注入 76%泛影葡胺 ( 10ml/kg体重 ,3gI(iodine) /10ml) ,DM组注射等量生理盐水。 3d后收集血标本检测血肌酐、血尿素氮 ;取肾脏组织 ,测定肾组织丙二醛 (MDA)与超氧化物歧化酶 (SOD)的含量。结果 :与正常对照组相比 ,糖尿病组 (DM组 )的MDA含量与SOD活性均明显升高 (P <0 .0 5 ) ;糖尿病大鼠注射造影剂 (CM组 ) 3d后MDA含量明显增加 ,SOD活性明显降低 ,与DM组差异有显著性 (P <0 .0 5 )。结论 :糖尿病大鼠造影剂肾病发生时 ,肾脏组织产生过氧化物增多、清除能力下降 ,提示氧化反应对糖尿病造影剂肾病的发生起一定作用 相似文献
96.
Psychosocial factors at work and perceived health among agricultural meat industry workers in France
Christine Cohidon Patrick Morisseau Francis Derriennic Marcel Goldberg Ellen Imbernon 《International archives of occupational and environmental health》2009,82(7):807-818
Objective The objective of this study was to describe the perceived health status of the meat industry employees—i.e., working in the
slaughtering, cutting, and boning of large animals and poultry—and its relation to their organisational and psychosocial constraints
at work.
Methods This postal survey included all 3,000 employees of the meat industry (beef, pork and poultry) in four districts in Brittany,
France, whose companies were affiliated with the agricultural branch of the national health insurance fund. The questionnaire
asked for social and demographic data and information describing their job and the organisation of their work. The psychosocial
factors at work were described according to Karasek’s questionnaire (demand, latitude and social support at work). Perceived
health was measured with the Nottingham Health Profile perceived health indicator.
Results This study shows the high prevalence of poor health reported by the workers in this industry. This poor perceived health was
worse in women and increased regularly with age. Among the psychosocial factors studied, high quantitative and qualitative
demand at work, inadequate resources for good work and to a lesser extent, inadequate prospects for promotion appear especially
associated with poor perceived health. Other factors often associated with poor perceived health included young age at the
first job and work hours that disrupt sleep rhythms (especially for women).
Conclusion Our results show that this population of workers is especially vulnerable from the point of view of perceived physical and
psychological health and is exposed to strong physical, organisational and psychosocial constraints at work. They also demonstrate
that poor perceived health is associated with some psychosocial (such as high psychological demand and insufficient resources)
and organisational factors at work. These results, in conjunction with those from other disciplines involved in studying this
industry, may help the companies to develop preventive activities. 相似文献
97.
Summary. Background: Pathological shear stress induces platelet aggregation that is dependent on von Willebrand factor (VWF) binding to glycoprotein (Gp)Ib‐IX‐V and phosphatidylinositol 3‐kinase activation. We tested the hypothesis that pathological shear stress stimulates phosphatidylinositol 3,4,5‐trisphosphate (PIP3) synthesis by directing the assembly of a molecular signaling complex that includes class IA phosphatidylinositol 3‐kinase (PI 3‐KIA). Methods: Platelets were subjected to 120 dynes cm?2 shear stress in a cone‐plate viscometer. Resting and sheared platelets were lyzed, immunoprecipitations of PI 3‐KIA performed, or lipids extracted for PIP3 measurements. α‐Actinin was incubated with phosphatidylinositol 4,5‐bisphosphate (PIP2), immunoprecipitated, and used as a substrate for in vitro PI 3‐KIA activity. Results: Pathological shear stress induces biphasic PIP3 production. In resting platelets, PI 3‐KIA associates with α‐actinin and PIP2. After exposure to shear stress, α‐actinin and PIP2 rapidly disassociate from PI 3‐KIA. PI 3‐KIA then gradually re‐associates with PIP2 and α‐actinin, and this complex becomes linked to GpIbα through the cytoskeleton. PIP3 production and the observed changes in the association between α‐actinin, PIP2, and PI 3‐KIA are inhibited when VWF binding to GpIbα is blocked. In a cell‐free system, α‐actinin binds PIP2 and when the α‐actinin–PIP2 complex is added to platelet PI 3‐KIA, PIP3 production is stimulated. Conclusions: These results suggest that pathological shear‐induced VWF binding to GpIb‐IX‐V stimulates PIP3 production through the assembly of an α‐actinin‐based complex that colocalizes PI 3‐KIA with substrate PIP2. 相似文献
98.
The kinetic dependence of the rate of oxidative phosphorylation (ADP/t) on the concentration of exogenous ADP has been mathematically analyzed in the brain mitochondria. This relationship has been approximated by a mathematic model under various vital conditions. We propose an analytical approach to calculating the characteristics of oxidative phosphorylation and predicting the kinetics of oxidative ATP synthesis in brain mitochondria of animals subjected to hypoxia. 相似文献
99.
Andrew R. Arthur 《Stress and health》2005,21(4):273-280
A previous study found that 86 per cent of employees (n = 111) who experience stress in the workplace and sought help from their workplace counselling schemes (Employee Assistance Programmes) had serious mental health problems, but the low participation rate (24 per cent) restricted generalizability and the measure used [General Health Questionnaire (GHQ‐12)] did not allow diagnosis. The present study (n = 58) improved the participation rate to 35 per cent and used a different version of the original measure (GHQ‐28) that allowed diagnostic differentiation as well as validation of the original findings. This new study found almost exactly the same high levels of mental health problems existed (86 per cent) in employees who remained at their work and that participants had higher rates of anxiety than depression. This finding is at variance with the usual co‐morbid presentation of anxiety and depression found in community based mental health services and suggests that depression may be an important differentiating factor between those who can remain at work and use counselling and those who cannot. There are implications for those who provide mental health services. The results of this study further reinforce the suggestion that workplace stress may be yet another name for common mental health problems that require professional help and treatment. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
100.
[目的]探讨持续顺应生理力线的压应力对犬骨盆弓状线部骨折愈合的影响.[方法]选用10只成年杂种家犬,双侧髋臼臼顶上方1.5 cm处横形截骨,分别采用ATMFS(骨盆髋臼三维记忆内固定系统)前柱固定器和5孔重建钢板内固定,于术后2、4、6、8、12周处死动物取材,行HE染色、Masson三色法染色组织学检查,图像分析新骨形成积分光密度值,研究不同应力作用模式下的骨盆骨折愈合情况.[结果]ATMFS侧软骨组织形成,骨皮质、骨小梁及胶原纤维成熟时间明显早于钢板侧,术后6、8、12周,两侧骨折端新骨生成面积之间存在显著性差异(P<0.05).[结论]ATMFS固定后于骨折端产生的持续顺应生理力线的压应力能够刺激骨折端成骨细胞的形成及骨胶原的合成与分泌,促进骨折早期愈合. 相似文献