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排序方式: 共有1022条查询结果,搜索用时 31 毫秒
81.
82.
Nanna Hurwitz Eller Morten BløndMartin Nielsen Jesper KristiansenBo Netterstrøm 《International journal of psychophysiology》2011,81(3):218-224
Objectives
The current study analyzed the relationship between psychosocial work environment assessed by the Effort Reward Imbalance Model (ERI-model) and heart rate variability (HRV) measured at baseline and again, two years later, as this relationship is scarcely covered by the literature.Methods
Measurements of HRV during seated rest were obtained from 231 public sector employees. The associations between the ERI-model, and HRV were examined using a series of mixed effects models. The dependent variables were the logarithmically transformed levels of HRV-measures. Gender and year of measurement were included as factors, whereas age, and time of measurement were included as covariates. Subject was included as a random effect.Results
Effort and effort reward imbalance were positively associated with heart rate and the ratio between low frequency (LF) and high frequency power (HF) and negatively associated with total power (TP) and HF. Reward was positively associated with TP.Conclusion
Adverse psychosocial work environment according to the ERI-model was associated with HRV, especially in the form of vagal withdrawal and most pronounced in women. 相似文献83.
Finnerup NB Pedersen LH Terkelsen AJ Johannesen IL Jensen TS 《Experimental neurology》2007,205(1):190-200
Central neuropathic pain is a debilitating and frequent complication to spinal cord injury (SCI). Excitatory input from hyperexcitable cells around the injured grey matter zone is suggested to play a role for central neuropathic pain felt below the level of a spinal cord injury. Direct evidence for this hypothesis is difficult to obtain. Capsaicin, activating TRPV1 receptors on small sensory afferents, induces enhanced cellular activity in dorsal horn neurons and produces a central mediated area of secondary hyperalgesia. We hypothesized that sensory stimuli and capsaicin applied at and just above the level of a spinal cord injury which already is hyperexcitable, would cause enhanced responses in patients with central pain at the level of injury compared to patients without neuropathic pain and healthy controls. Touch, punctuate stimuli, cold stimuli and topical capsaicin was applied above, at, and below injury level in 10 SCI patients with central pain below a thoracic injury, in 10 SCI patients with a thoracic injury but without neuropathic pain, and in corresponding areas in 10 healthy control subjects. The study found increased responses to touch at injury level compared to controls (p = 0.033) and repetitive punctuate stimuli above and at injury level compared to controls and pain-free SCI patients (p < 0.04) but not an increased response to capsaicin in patients with central pain. These results suggest that SCI patients with below-level pain have increased responses to some but not all sensory input at the level of injury. 相似文献
84.
The K+ channels Kir4.1 and Kir4.1–Kir5.1 are expressed in the glial cells of the CNS and are involved in regulation of the K+ homeostasis. Several studies have shown that Kir4.1 channels are co-localized with aquaporins (AQP4) in the glial endfeet, and a putative functional coupling between the Kir channels and aquaporins is therefore debated. To test a possible volume-sensitivity of the Kir channels, the Kir4.1 or Kir4.1–Kir5.1 channels were expressed in Xenopus oocytes with or without co-expression of aquaporins and subsequently exposed to cell volume alterations. Our results show an increase in Kir4.1 and Kir4.1–Kir5.1 currents upon swelling of the oocytes and a reduction in the current when the oocytes were shrunk. The volume-dependent changes in channel activity were not due to changes in the kinetics of the channels. These findings implicate a putative functional interaction between the Kir channels and aquaporins via small, fast cell volume changes in the glial cells. 相似文献
85.
BACKGROUND: Iron deficiency leading to low hemoglobin concentration (cHb) is a common problem for blood donors as well as for blood banks. A standardized protocol offering iron supplementation based on P-ferritin determination may help to reduce the problem and retain donors. STUDY DESIGN AND METHODS: This was a prospective study where 879 blood donors, presenting with cHb at or below the limit of acceptance for donation, were included. The predonation cHb result was read after donation. The donors received 50 iron tablets (JernC or Ferrochel, 100 or 25 mg elemental iron, respectively), and samples for P-ferritin, mean corpuscular volume, and control of cHb were secured. Based on a P-ferritin level of less than 60 microg per L, 20 iron tablets were offered after all following donations. RESULTS: Mean cHb was 7.6 mmol per L (122 g/L) and 8.2 mmol per L (132 g/L) in women and men, respectively. In 80 percent of the women and 48 percent of the men, iron stores were low (P-ferritin < or = 30 microg/L). In the donors returning once or twice, an increase in cHb and P-ferritin was seen. Fifteen donors were permanently deferred due to disease and 36 due to low cHb, but 2 years after the start of the study, 79 percent of the women and 85 percent of the men were still active donors. CONCLUSION: A standardized protocol offering iron supplementation and simple oral and written advice based on P-ferritin measurements is effective in normalizing cHb and retaining donors presenting with cHb at or below the limit of acceptance for donation. 相似文献
86.
87.
Waldron E Heilig C Schweitzer A Nadella N Jaeger S Martin AM Weggen S Brix K Pietrzik CU 《Neurobiology of disease》2008,31(2):188-197
The amyloid beta peptide (Aβ) is a central player in Alzheimer's disease (AD) pathology. Aβ liberation depends on APP cleavage by β- and γ-secretases. The low density lipoprotein receptor related protein 1 (LRP1) was shown to mediate APP processing at multiple steps. Newly synthesized LRP1 can interact with APP, implying an interaction between these two proteins early in the secretory pathway. We wanted to investigate whether LRP1 mediates APP trafficking along the secretory pathway, and, if so, whether it affects APP processing. Indeed, the early trafficking of APP within the secretory pathway is strongly influenced by its interaction with the C-terminal domain of LRP1. The LRP1-construct expressing an ER-retention motif, LRP-CT KKAA, had the capacity to retard APP traffic to early secretory compartments. In addition, we provide evidence that APP metabolism occurs in close conjunction with LRP1 trafficking, highlighting a new role of lipoprotein receptors in neurodegenerative diseases. 相似文献
88.
Rosenberg C Lauritzen L Brix J Jørgensen JB Kofod P Bayer LB 《Psychopharmacology bulletin》2007,40(1):63-73
This double-blind, multicenter trial, carried out in general practice in Denmark, comprised 221 women and 70 men, aged 58 to 97 years, with major depression (with or without mild cognitive dysfunction) or dysthymia (DSM-III-R). Patients had a total score > or =13 on the 17-item Hamilton Depression Rating Scale (HDRS) and a score > or =20 on the Mini Mental State Examination scale. The efficacy and tolerability of citalopram (20-40 mg daily) and amitriptyline (50-100 mg daily) were compared over 12 weeks. The participating general practitioners were trained at corating sessions in the use of the HDRS and Melancholia Scale (MES) prior to and during the study. The inter-observer reliability was assessed to investigate if general practitioners were able to use scales that measure the severity of depression. The two treatments were considered equally effective; the 90% confidence interval for the difference between the treatment groups in change from baseline to end-point in HDRS total score (-0.84 to +1.23) was within the predefined interval (-4 to +4). Significantly more patients on citalopram (50%) than on amitriptyline (31%) reported no adverse events at all (P = .001). Moreover, patients on amitriptyline reported adverse events significantly earlier and more frequently than patients on citalopram. The inter-observer reliability was highly satisfactory, with intra-class correlation coefficients (ICC-U) of .83 for the HDRS and .82 for the MES; however, the ICC-U for the Clinical Global Impressions was .54, indicating a poorer consensus in the investigators clinical judgment. Training in the use of the HDRS and MES scales improved the inter-observer reliability. 相似文献
89.
Manuela Aguirre Ulloa Samantha Nesrallah Pardis Shafafi Angel Lamar Pedro Côrte-Real Gonçalves Mafalda Gonçalves Karoline Steen Nylander Aleksandra Luszczynska Nanna Lien Elin Bergstrøm Harry Rutter Henriette Marki Knut-Inge Klepp Claire Bouillon 《Obesity reviews》2023,24(Z2):e13611
While obesity prevention represents an established field of research, the inclusion of young people, who are regularly cited as an important priority group, are rarely actioned in long-term studies. This paper focuses on the development of a dialogue tool intended to tackle this issue, engaging, and eliciting insights on the theme of obesity prevention, by young people and for young people. As part of the CO-CREATE project, this tool was co-developed by designers, public health, and youth participation experts, researchers, and young people. Co-creation is a key methodology in the design of the dialogue tool, as young people were involved in all stages of the development process. This paper elaborates on the process of co-designing a dialogue tool that helps explore obesity prevention policy ideas from multiple perspectives, and describes the design principles that informed the process and the final versions of the tool. The purpose of the Dialogue Forum tool is for youth to engage policymakers and other relevant stakeholders to discuss and refine co-created and youth-initiated ideas for healthier food and physical activity environments. We analyze how specific design principles were integrated into different prototypes and the value of this within the project and the field. 相似文献
90.
Anaely Aguiar Furkan Önal Gaironeesa Hendricks Laurence Blanchard Eduard Romanenko Anne-Siri Fismen Emmanuel Nwosu Sondre Herstad Natalie Savona Janetta Harbron Cécile Knai Oddrun Samdal Harry Rutter Nanna Lien Mohammad S. Jalali Birgit Kopainsky 《Obesity reviews》2023,24(Z2):e13628
Both obesity and poor mental wellbeing have a high prevalence in European youth. Adolescents in six countries identified mental wellbeing factors as main drivers of youth obesity through systems mapping. This study sought to (1) explore the dynamics of the interplay between poor mental wellbeing, energy balance-related behaviors, and adolescent overweight and obesity prevalence and (2) test the effect of intervention point scenarios to reduce adolescent obesity. Drawing on the youth-generated systems maps and a literature synthesis, we built a simulation model that represents the links from major feedback pathways for poor mental wellbeing to changes in dietary, physical activity, and sleep behaviors. The model was calibrated using survey data from Norway, expert input, and literature and shows a good fit between simulated behavior and available statistical data. The simulations indicate that adolescent mental wellbeing is harmed by socio-cultural pressures and stressors, which trigger reinforcing feedback mechanisms related to emotional/binge eating, lack of motivation to engage in physical activity, and sleep difficulty. Targeting a combination of intervention points that support a 25% reduction of pressure on body image and psychosocial stress showed potentially favorable effects on mental wellbeing—doubling on average for boys and girls and decreasing obesity prevalence by over 4%. 相似文献