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排序方式: 共有2142条查询结果,搜索用时 34 毫秒
1.
Laura van Dussen Jurgen H Runge Michael W Tanck Erik Endert Annemieke C Heijboer Eric Fliers Carla E Hollak Erik M Akkerman Peter H Bisschop 《Journal of bone and mineral research》2015,30(11):2058-2066
Bone marrow fat, an unique component of the bone marrow cavity increases with aging and menopause and is inversely related to bone mass. Sex steroids may be involved in the regulation of bone marrow fat, because men have higher bone marrow fat than women and clinical observations have suggested that the variation in bone marrow fat fraction is greater in premenopausal compared to postmenopausal women and men. We hypothesized that the menstrual cycle and/or estrogen affects the bone marrow fat fraction. First, we measured vertebral bone marrow fat fraction with Dixon Quantitative Chemical Shift MRI (QCSI) twice a week during 1 month in 10 regularly ovulating women. The vertebral bone marrow fat fraction increased 0.02 (95% CI, 0.00 to 0.03) during the follicular phase (p = 0.033), and showed a nonsignificant decrease of 0.02 (95% CI, –0.01 to 0.04) during the luteal phase (p = 0.091). To determine the effect of estrogen on bone marrow fat, we measured vertebral bone marrow fat fraction every week for 6 consecutive weeks in 6 postmenopausal women before, during, and after 2 weeks of oral 17‐β estradiol treatment (2 mg/day). Bone marrow fat fraction decreased by 0.05 (95% CI, 0.01 to 0.09) from 0.48 (95% CI, 0.42 to 0.53) to 0.43 (95% CI, 0.34 to 0.51) during 17‐β estradiol administration (p < 0.001) and increased again after cessation. During 17‐β estradiol administration the bone formation marker procollagen type I N propeptide (P1NP) increased (p = 0.034) and the bone resorption marker C‐terminal crosslinking telopeptides of collagen type I (CTx) decreased (p < 0.001). In conclusion, we described the variation in vertebral bone marrow fat fraction among ovulating premenopausal women. And among postmenopausal women, we demonstrated that 17‐β estradiol rapidly reduces the marrow fat fraction, suggesting that 17‐β estradiol regulates bone marrow fat independent of bone mass. © 2015 American Society for Bone and Mineral Research. 相似文献
2.
Liselotte M. Klitsie Arno A. W. Roest Nico A. Blom Arend D. J. ten Harkel 《Pediatric cardiology》2014,35(1):3-15
A varying degree of impairment of ventricular performance is observed over the long-term after surgery for a congenital heart defect (CHD). Impaired ventricular performance has been shown to be of prognostic value for increased risk of cardiovascular events in adult CHD patients. This emphasizes the importance of delineating the timing and cause of this postoperative impairment. Impairment of ventricular performance could develop over time as a consequence of residua, sequelae and complications of the CHD or surgical procedure. Yet, impaired ventricular performance has also been observed immediately after surgery and can persist and/or worsen over time. This postoperative impairment of ventricular performance is the focus of this review. This article provides an overview of echocardiographic techniques currently used to assess ventricular performance. Furthermore, we review current literature describing ventricular performance, as assessed using echocardiography, after correction of a CHD. In general, a decrease in ventricular performance is observed directly after surgery for CHD’s. Subsequent follow-up of ventricular performance is characterized by a varying degree of postoperative recovery. A consistent observation is the persistent impairment of right-ventricular performance after repair in several different subgroups of CHD patients ranging from ventricular septal defect repair to surgery for Tetralogy of Fallot. 相似文献
3.
Ritter DE Gandini LG Pinto Ados S Ravelli DB Locks A 《World journal of orthodontics》2006,7(3):279-285
Optimal facial esthetics is one of the objectives in orthodontic treatment and an important issue in modern society. In this context, orthodontic treatment permits individuals with dental malpositions to achieve improved dentofacial esthetics. To reach this result, the orthodontist needs to recognize the characteristics considered normal and pleasant in dental arches and smiles. The objective of this article is to review and discuss criterion adopted by dental literature to technically analyze the smile, such as dental midline, smile line, dental exposure, negative space, dental proportion, and symmetry. This article proposes a way to visualize an ideal smile for each patient. 相似文献
4.
Jessy A. Terpstra Rosalie van der Vaart Saskia Spillekom-van Koulil Arno van Dam Judith G.M. Rosmalen Hans Knoop Henriët van Middendorp Andrea W.M. Evers 《Patient education and counseling》2018,101(9):1702-1707
Objective
Online cognitive-behavioral therapy (iCBT) is effective in supporting patients’ self-management. Since iCBT differs from face-to-face CBT on several levels, proper training of therapists is essential. This paper describes the development and evaluation of a therapist training based on theoretical domains that are known to influence implementation behavior, for an iCBT for chronic pain.Methods
The training consists of 1.5?days and covers the implementation domains “knowledge”, “skills”, “motivation”, and “organization”, by focusing on the therapy’s rationale, iCBT skills, and implementation strategies. Using an evaluation questionnaire, implementation determinants (therapist characteristics, e-health attitude, and implementation domains) and iCBT acceptance were assessed among participants after training.Results
Twenty-two therapists participated, who generally showed positive e-health attitudes, positive implementation expectations, and high iCBT acceptance. Organizational aspects (e.g., policy regarding iCBT implementation) were rated neutrally.Conclusions
An iCBT therapist training was developed and initial evaluations among participants showed favorable implementation intentions.Practice implications
Therapists’ positive training evaluations are promising regarding the dissemination of iCBT in daily practice. Organizational support is vital and needs to be attended to when selecting organizations for iCBT implementation. 相似文献5.
Thomas Oosterhof Igor I Tulevski Arno A W Roest Paul Steendijk Hubert W Vliegen Ernst E van der Wall Albert de Roos Jan G P Tijssen Barbara J M Mulder 《Journal of cardiovascular magnetic resonance》2005,7(2):383-389
BACKGROUND: In patients with an intra-atrial correction for transposition of the great arteries (TGA) an abnormal response to stress testing is common. However, hemodynamic responses may vary substantially when different stress tests are used. We compared the hemodynamic response to dobutamine stress with the response to physical exercise in patients and controls. METHODS: Thirty-nine patients and 25 age/sex-matched control subjects underwent either dobutamine stress (15 microg/kg/min) or submaximal physical exercise cardiovascular magnetic resonance. End-systolic and end-diastolic right ventricular volumes (ESV; EDV) were determined. Five representative patients underwent both stress tests. For these patients, wall thickening reserve was calculated as systolic wall thickening during stress minus systolic wall thickening at rest. RESULTS: In controls, dobutamine stress and physical exercise showed similar responses: stroke volume, cardiac output, and ejection fraction increased significantly, whereas ESV decreased significantly and EDV was unchanged. In patients, stroke volume did not increase with either dobutamine or exercise (-8.6% vs. 2.9%). Ejection fraction increased significantly with dobutamine (16%, p < 0.001) but tended to decrease during exercise (-2.1%, P = NS). EDV and ESV decreased during dobutamine but were unchanged during exercise. (-22% vs. 5.0%, P < 0.001; -36% vs. 9.0%, P < 0.01 respectively). Wall thickening reserve was higher with dobutamine than with exercise (0.9 mm vs. -0.6 mm, P = 0.02). CONCLUSION: Dobutamine stress and physical exercise cannot be used interchangeably for assessment of systolic and diastolic function in patients with an intra-atrial correction for TGA. This may have consequences for the use of different stress CMR approaches in the clinical setting. 相似文献
6.
Host and environmental effects on plasma apolipoprotein B 总被引:2,自引:0,他引:2
Gail Pairitz Jarvik Ellen Wijsman Ruth E. Little John J. Albers Arno G. Motulsky John D. Brunzell 《International Journal of Clinical & Laboratory Research》1993,23(1-4):215-220
Summary In this study, levels of apo B in an unselected sample of 487 middle-aged Caucasian spouses of patients and spouses of the
patients’ relatives are described. In males, apo B levels increased with age until the 7th decade, then declined; apo B levels
in females, which were lower than in males, increased linearly with age across the entire life-span. Height and weight, smoking,
and presence of noninsulin-dependent diabetes mellitus significantly influenced age- and gender-adjusted apo B levels in this
sample, whereas use of alcohol, diuretics, β-blockers, or insulin did not. Age, gender, height, weight, smoking, and noninsulin-dependent
diabetes mellitus account for 21% of the total variation in apo B levels in this sample. 相似文献
7.
Background
It is generally assumed that integrated care has a cost-saving potential in comparison with traditional care. However, there is little evidence on this potential with respect to integrated nursing home care.Aims and objectives
•
To portray the costs of traditional and integrated nursing home care. •
To explore the cost-saving potential of integrated care.
Design/methods/settings/participants
Between 1999 and 2003, formal and informal caregivers of different nursing homes in the Netherlands recorded activities performed for residents with somatic or psycho-social problems. In total, 23,380 lists were analysed to determine the average costs of formal and informal care per activity, per type of resident and per nursing home care type. For formal care activities, the total personnel costs per minute (in Euro) were calculated. For informal care costs, two shadow prices were used.Results
Compared to traditional care, integrated care had lower informal direct care costs per resident and per activity and lower average costs per direct activity (for a set of activities performed by formal caregivers). The total average costs per resident per day and the costs of formal direct care per resident, however, were higher as were the costs of delivering a set of indirect activities to residents with somatic problems.Conclusions
The general assumption that integrated care has a cost-saving potential (per resident or per individual activity) was only partially supported by our research. Our study also raised issues which should be investigated in future research on integrated nursing home care. 相似文献8.
9.
Purpose:
To evaluate the use of a novel real‐time magnetic resonance imaging (MRI) technique for the assessment of normal swallowing dynamics.Materials and Methods:
In a cohort of 10 healthy subjects, real‐time MRI movies at 24.3 frames per second were obtained in sagittal, coronal, and axial orientation during self‐controlled swallows of 5 mL pineapple juice as oral contrast bolus. All studies were performed with the use of a commercial MRI system at 3 T combining two sets of radiofrequency receiver coils. Real‐time movies relied on a fast low‐angle shot (FLASH) MRI sequence with radial undersampling and image reconstruction by nonlinear inversion yielding 41.23 msec acquisition time for an in‐plane resolution of 1.5 mm. Evaluations focused on clinical image quality as well as visualization and temporal quantification of distinct swallowing functions.Results:
Throughout the entire process, the swallowing dynamics were well depicted and characterized with almost no visible image artifacts in all subjects. The mid‐sagittal plane turned out to be most valuable. The movies allowed for a quantitative determination of the temporal pattern of all swallowing events.Conclusion:
The proposed real‐time MRI technique yields noninvasive, robust, and quantitative access to the physiology of normal swallowing in healthy subjects at high temporal resolution and image quality. J. Magn. Reson. Imaging 2012;35:1372–1379. © 2012 Wiley Periodicals, Inc. 相似文献10.
Heikkinen Aki T. Friedlein Arno Matondo Mariette Hatley Oliver J. D. Petsalo Aleksanteri Juvonen Risto Galetin Aleksandra Rostami-Hodjegan Amin Aebersold Ruedi Lamerz Jens Dunkley Tom Cutler Paul Parrott Neil 《Pharmaceutical research》2015,32(1):74-90
Pharmaceutical Research - Beagle dogs are used to study oral pharmacokinetics and guide development of drug formulations for human use. Since mechanistic insight into species differences is needed... 相似文献