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排序方式: 共有4139条查询结果,搜索用时 17 毫秒
41.
Hossein Haji Ali Afzali Jodi Gray Jonathan Karnon 《Applied health economics and health policy》2013,11(2):85-93
Decision analytic models play an increasingly important role in the economic evaluation of health technologies. Given uncertainties around the assumptions used to develop such models, several guidelines have been published to identify and assess ‘best practice’ in the model development process, including general modelling approach (e.g., time horizon), model structure, input data and model performance evaluation. This paper focuses on model performance evaluation. In the absence of a sufficient level of detail around model performance evaluation, concerns regarding the accuracy of model outputs, and hence the credibility of such models, are frequently raised. Following presentation of its components, a review of the application and reporting of model performance evaluation is presented. Taking cardiovascular disease as an illustrative example, the review investigates the use of face validity, internal validity, external validity, and cross model validity. As a part of the performance evaluation process, model calibration is also discussed and its use in applied studies investigated. The review found that the application and reporting of model performance evaluation across 81 studies of treatment for cardiovascular disease was variable. Cross-model validation was reported in 55 % of the reviewed studies, though the level of detail provided varied considerably. We found that very few studies documented other types of validity, and only 6 % of the reviewed articles reported a calibration process. Considering the above findings, we propose a comprehensive model performance evaluation framework (checklist), informed by a review of best-practice guidelines. This framework provides a basis for more accurate and consistent documentation of model performance evaluation. This will improve the peer review process and the comparability of modelling studies. Recognising the fundamental role of decision analytic models in informing public funding decisions, the proposed framework should usefully inform guidelines for preparing submissions to reimbursement bodies. 相似文献
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Bizhan Helli Majid Mohammad Shahi Karim Mowla Mohammad Taha Jalali Hossein Khadem Haghighian 《Phytotherapy research : PTR》2019,33(9):2421-2428
Inflammation is one of the main characteristics of rheumatoid arthritis. Based on the antiinflammatory properties of sesame, this study was conducted to evaluate the sesamin supplement effects on serum levels of some proteolytic enzymes, inflammatory biomarkers, and clinical indices in women with rheumatoid arthritis. In this randomized, triple‐blind, placebo‐controlled clinical trial, 44 patients were randomly divided in intervention and control groups. Patients received 200‐mg/day sesamin supplement or placebo in the intervention and control group for 6 weeks. Serum levels of proteolytic enzymes (hyaluronidase, aggrecanase, and matrix metalloproteinases‐3) and inflammatory biomarkers (hs‐CRP, IL‐1β, IL‐6, TNF‐α, and cyclooxygenase‐2) were measured with enzyme‐linked immunosorbent assay method at the beginning and end of the study. After intervention, serum levels of hyaluronidase and matrix metalloproteinases‐3 decreased significantly in sesamin group. Also, serum levels of hs‐CRP, TNF‐α, and cyclooxygenase‐2 in intervention group were significantly decreased in intervention group compared with placebo group. Sesamin supplementation also caused a significant reduction in the number of tender joints and severity of pain in these patients. According to the results, it seems that the sesamin by reducing inflammatory mediators can relieve clinical symptoms and pathological changes that caused by inflammatory impairment in patients with rheumatoid arthritis. 相似文献
44.
Amrollah Sharifi Homayoon Vahedi Saharnaz Nedjat Hossein Rafiei Mohammad Javad Hosseinzadeh‐Attar 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2019,127(10):681-687
Ulcerative colitis (UC) is a chronic recurrent inflammation of the colon. It has been proposed that the UC pathogenesis may be related to vitamin D deficiency and/or vitamin D administration in UC patients may have an ameliorating effect on the intestinal inflammation. The aim of this study was to assess the effect of vitamin D on the serum levels of immune cytokines in UC patients. In this double‐blind randomized controlled trial, 90 mild‐to‐moderate UC patients were assigned to get either a single muscular injection of 7.5 mg vitamin D3 or 1 mL normal saline as placebo. Three months later serum levels of IL‐4, IL‐10, IL‐12p70, IFN‐γ, and TNF‐α were measured. Two group variables were compared using independent t‐test and analysis of covariance (ANCOVA). There was a significant increase in vitamin D only in the vitamin D group. Compared to placebo, vitamin D had significant decreasing effects on serum TNF‐α, IFN‐γ, and IL12p70 levels, but it had no significant effect on serum levels of IL4 and IL10. Vitamin D seems to inhibit Th1 immune responses and have no effect on Th2 responses. The findings of this study support several in vitro studies, which suggest a therapeutic immunomodulatory potential of vitamin D. 相似文献
45.
Mehdi Mogharnasi Hossein TaheriChadorneshin Seyed Amin Papoli-Baravati Asma Teymuri 《Disability and health journal》2019,12(1):29-34
Background
As a recently discovered adipokine, nesfatin-1 is conducive to insulin sensitivity, lipid profile, energy balance, and probably obesity.Objective
The aim of the present study was to investigate the effect of upper-body resistance exercise training (RET) on nesfatin-1 levels, insulin resistance, lipid profile, and body composition in obese paraplegic men.Methods
Twenty obese paraplegic men were randomly assigned into control and upper-body RET groups. Upper-body RET was performed for 8 weeks, 3 sessions per week at an intensity corresponding to 60–80% maximum amount of force that can be generated in one maximal contraction in 5 stations (bench press, seated rows, sitting lat pulldown, arm extension, and arm curls). Body fat percentage was determined according to 4-sites skinfold protocol of Durnin and Womersley and Siri equation. Obesity for spinal cord injury patients in the current study was set at BMI >22?kg/m2. Data were statistically analyzed by paired and independent t-test (P?<?0.05).Results
We found significant improvements in serum levels of nesfatin-1 (21.13%), insulin sensitivity (8.95%), and high-density lipoprotein (10.87%). Other lipid profile markers, i.e. low-density lipoprotein (4.32%), cholesterol (8.20%), and triglyceride (15.10%) reduced significantly after upper-body RET. Moreover, upper-body RET led to a significant reduction in body mass index (2.36%), body fat percentage (2.79%), and waist-to-hip ratio (2.40%).Conclusion
Upper-body RET improved insulin sensitivity, lipid profile, and body composition in paraplegic men. Serum nefastin-1 may be a potential marker of success in weight management in this population. 相似文献46.
Mohammad Hossein Gharache Seyed Yousef Paighambary Amin Golpour 《Comparative clinical pathology》2014,23(4):979-982
The aim of current research was to determine hematological and biochemical parameters of captured kutum with gill net and beach seine. A total of 16 matured kutums were used for blood sampling from each device. The result showed significant differences in white blood cells, red blood cell, mean corpuscle volume, Ca2+, Cl?, and cholesterol between gill net and beach seine methods, but there were no significant differences in other parameters. Based on obtained results during our experiment, we concluded that the stress due to capture can influence the blood parameters, and different capture methods lead to different reactions in blood parameters. 相似文献
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MH Esmaeili M Movahedi A Faraji H Haghdoost-Yazdi 《Neurotoxicology and teratology》2012,34(5):489-494
β-Carbolines (BCs) are considered to be endogenous toxins and have been proposed as possible causative candidates inducing Parkinson's disease (PD). However, there is controversy about the effect and also effective dose of these compounds in the etiology of PD. This study was designed to further examine the effect of norharman (NH), a BC which in mammalian brain occurs at high levels in the substantia nigra, on the development of Parkinsonism-like behaviors in rats. A small amount (4μl) of NH solution at 2 or 200ng/ml was unilaterally injected into either striatum or substantia nigra (SN) by stereotaxic surgery. The development of Parkinsonism was assessed by three conventional behavioral tests, compared to the effects of unilateral 6-hydroxydopamine (6-OHDA) - induced lesions in the nigrostriatal pathway. An apomorphine-induced rotational test revealed no Parkinsonism-like behavior in the NH treated groups. However, rats that received the high concentration of NH into their SN showed significant biased swings in the elevated body swing test. In a rotarod test, NH treated groups showed relatively weak motor performance and their learning patterns were close to that of the 6-OHDA treated rats. Considering that the rotational test is only valid in animals with severe Parkinsonism, but time spent on the rotating rod correlates inversely with severity of Parkinsonism, our results indicate that a single exposure to low amounts of NH is effective in producing moderate Parkinsonism-like behavioral symptoms, possibly through a neurotoxic effect of this agent on the SN dopaminergic neurons. 相似文献