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991.
This study examined cardiovascular responses as a function of time following exercise in which participants were exposed to a laboratory stressor. Ninety (42 women) young (18-35 years old) nonsmoking normotensive participants engaged in 30 min of high and low intensity (75-80% and 50-55% VO(2) max) aerobic exercise and a sedentary control condition. Participants were randomly assigned to a laboratory stressor 5, 30, or 60 min following the exercise bout. Results indicate that low and high intensity exercise significantly reduce heart rate (HR) and systolic and diastolic blood pressure reactivity and HR recovery values. An inverse relationship between intensity of exercise and subsequent cardiovascular reactivity was found. These findings suggest attenuated stress responses following acute exercise depend both on exercise intensity and the time of exposure to psychological stress following exercise. 相似文献
992.
Holzapfel GA Sommer G Auer M Regitnig P Ogden RW 《Annals of biomedical engineering》2007,35(4):530-545
Data relating to residual deformations in human arteries are scarce. In this paper we investigate three-dimensional residual
deformations for intact strips and for their separate layers from human aortas in their passive state. From 11 abdominal aortas
with identified anamnesis, 16 pairs of rings and axial strips were harvested, and the rings cut open. After 16 h images of
the resulting geometries were recorded, and the strips were separated into their three layers; after another 6 h images were
again recorded. Image processing and analysis was then used to quantify residual stretches and curvatures. For each specimen
histological analysis established that the intima, media and adventitia were clearly separated, and the separation was atraumatic.
Axial in situ stretches were determined to be 1.196 ± 0.084. On separation, the strips from the adventitia and media shortened (between
4.03 and 8.76% on average), while the intimal strips elongated on average by 3.84% (circumferential) and 4.28% (axial) relative
to the associated intact strips. After separation, the adventitia from the ring sprang open by about 180° on average, becoming
flat, the intima opened only slightly, but the media sprang open by more than 180° (as did the intact strip). The adventitia
and intima from the axial strips remained flat, while the media (and the intact strip) bent away from the vessel axis. This
study has shown that residual deformations are three dimensional and cannot be described by a single parameter such as ‘the’
opening angle. Their quantification and modeling therefore require consideration of both stretching and bending, which are
highly layer-specific and axially dependent. 相似文献
993.
Macht M Gerlich C Ellgring H Schradi M Rusiñol AB Crespo M Prats A Viemerö V Lankinen A Bitti PE Candini L Spliethoff-Kamminga N de Vreugd J Simons G Pasqualini MS Thompson SB Taba P Krikmann U Kanarik E 《Patient education and counseling》2007,65(2):245-252
OBJECTIVE: To evaluate a newly developed education programme for Parkinson's disease (PD) patients. METHODS: The programme consisted of eight sessions and aimed at improving knowledge and skills related to self-monitoring, health promotion, stress management, depression, anxiety, social competence, and social support, all with special reference to PD. The programme was formatively evaluated in seven European countries (Spain, Finland, Italy, The Netherlands, United Kingdom, Estonia, Germany) with 151 patients diagnosed with idiopathic PD. The evaluation included patients' ratings of the comprehensibility and feasibility of the programme as well as mood ratings before and after each session. Patients also completed questionnaires at the beginning and end of the programme to explore possible changes in disease-related psychosocial problems, quality of life, and depression. RESULTS: The programme was feasible to run, and patients were able to understand its elements. Patients reported mood elevations following individual sessions and reduced disease-related psychosocial problems after completing the programme. There were no substantial differences in results between cultures. CONCLUSION: Patient education appears to have potential as a useful and feasible intervention, complementing medical treatment in PD. PRACTICE IMPLICATIONS: The present programme will soon be available in seven European languages and can be tested in different health care systems. 相似文献
994.
Rysz J Błaszczak R Banach M Kedziora-Kornatowska K Kornatowski T Tański W Kedziora J 《Archivum immunologiae et therapiae experimentalis》2007,55(5):335-340
Introduction: The aim of the study was to evaluate some selected parameters of the antioxidative system in patients with type 2 diabetes.
Materials and Methods: Eighty-one type 2 diabetes patients took part in the study (39 patients with metabolically balanced and 42 with metabolically
unbalanced diabetes). The control group consisted of 30 healthy people. The total antioxidant capacity of plasma was measured
fluorometrically using phycoerythrin. To calculate the low-molecular-weight antioxidant concentration in the plasma samples,
the duration of Trolox activity as a function of its concentration in the sample was measured. The activity of antioxidative
enzymes in red blood cells was determined using the Misra and Fridovich method and Beers and Sizer method.
Results: The total plasma antioxidant capacity and the low-molecular-weight antioxidant concentration in the group of patients with
metabolically compensated type 2 diabetes were statistically significantly higher than in the group of patients with metabolically
uncontrolled diabetes. The activity of antioxidative enzymes was found to be higher in the group of type 2 diabetes patients
at the stage of metabolic balance.
Conclusions: The obtained results confirm the thesis of glucose toxicity and intensification of oxidative stress in patients with diabetes. 相似文献
995.
Lakomkin VL Kapel'ko VI Lankin VZ Konovalova GG Kaminnyi AI 《Bulletin of experimental biology and medicine》2007,143(4):408-410
Long-term administration of β-hydroxy-β-methylglutaryl coenzyme A reductase inhibitor atorvastatin to rats was accompanied
by an increase in the relative weight of the heart and decrease in the rate of pressure development in the isovolumic heart.
During oxidative stress induced by addition of 100 μM H2O2 to the perfusate, the decrease in contractile function was more pronounced that in the control. Our results indicate that
administration of atorvastatin is accompanied by a decrease in myocardial contractility, which becomes more pronounced under
conditions of oxidative stress.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 143, No. 4, pp. 383–385, April, 2007 相似文献
996.
The present study enumerates the attenuating effects of curcumin and α-tocopherol against propoxur induced oxidative DNA damage in human peripheral blood mononuclear cells (PBMC). Cultured cells were isolated from peripheral blood of healthy volunteers, and were exposed to varying concentrations of propoxur (0–21?μg/ml) for 6, 12, and 24?h, and in combination with curcumin (9.2?μg/ml) or α-tocopherol (4.3?μg/ml) or both. Cytotoxic effect of propoxur was examined by MTT assay. The role of oxidative stress beneath the cytotoxicity of propoxur was evaluated by the measurement of reduced glutathione (GSH), malondialdehyde (MDA) and 8-hydroxy-2′-deoxyguanosine (8-OH-dG) levels in cell lysate. A concentration-dependent cell death, depletion of GSH, an increase in the level of both MDA and 8-OH-dG were observed. Co-treatment with curcumin or α-tocopherol significantly attenuates depleted GSH, decrease in MDA and 8-OH-dG levels in propoxur exposed cells (p?0.05). The results of the present study provide experimental evidence of involvement of oxidative stress in propoxur-mediated genotoxicity in human PBMC and highlight the antioxidant role of curcumin and α-tocopherol following propoxur exposure. 相似文献
997.
998.
Post Traumatic Stress Disorder (PTSD) and chronic pain have been identified as global health challenges for health professionals, and there is a robust literature linking PTSD and chronic pain. Much of the research is focused on high-income countries, leaving a serious gap when chronic pain is considered globally. Using the concept of Continuous Traumatic Stress (CTS), we look at how broader social conditions impact on the experience of chronic pain. We review the relevant literature on chronic pain, PTSD, and CTS, and suggest a research agenda for a more globally relevant and contextual understanding of chronic pain. 相似文献
999.
Kiran Kumar Soni Li Tao Zhang Bo Ram Choi Keshab Kumar Karna Jae Hyung You Yu Seob Shin 《Pharmaceutical biology》2018,56(1):94-103
Context: MOTILIPERM was prepared as a mixture of extracts of three medicinal herbs [roots of Morinda officinalis How (Rubiaceae), outer scales of Allium cepa L. (Liliaceae) and seeds of Cuscuta chinensis Lamark (Convolvulaceae)].Objective: To investigate the role of reactive oxygen species (ROS)-based endoplasmic reticulum (ER) stress in a rat model of varicocele and the therapeutic efficacy of MOTILIPERM in this model.Materials and methods: Sixty male rats were divided into five experimental groups: a normal control group (CTR?+?vehicle), a control group administered MOTILIPERM 200?mg/kg (CTR?+?M 200), a varicocele-induced control group (VC?+?vehicle) and two varicocele-induced groups administered MOTILIPERM 100 (VC?+?M 100) or 200 (VC?+?M 200) mg/kg for 4 weeks. Testis weights were recorded and serums were assayed for hormone concentrations. Tissues were subjected to semen analysis, histopathology, analyses of ER response protein expression levels and oxidative stress were assessed by measuring ROS, reactive nitrogen species (RNS), malondialdehyde (MDA) level and ratios of total glutathione (GSH)/oxidized GSH (GSSG).Results: MOTILIPERM treatment of varicocele-induced groups significantly increased left testis weight, testosterone level, sperm motility, count and spermatogenic cell density. ER-response protein expression levels were dose-dependently decreased in VC?+?M 200 group compared with VC?+?vehicle group. MOTILIPERM treatment also decreased MDA and ROS/RNS level but increased GSH/GSSG ratio.Discussion and conclusions: This study suggests that ROS-related ER stress may play a major role in varicocele-induced infertility and MOTILIPERM, a novel compound targeting ROS-based ER stress, may be therapeutically useful in treatment of varicocele, or as a supplement for the treatment of infertility. 相似文献
1000.