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排序方式: 共有557条查询结果,搜索用时 31 毫秒
551.
Chumlea WC Cesari M Evans WJ Ferrucci L Fielding RA Pahor M Studenski S Vellas B;International Working Group on Sarcopenia Task Force Members 《The journal of nutrition, health & aging》2011,15(6):450-455
Sarcopenia is the age-related involuntary loss of skeletal muscle mass and functionality that can lead to the development
of disability, frailty and increased health care costs. The development of interventions aimed at preventing and/or treating
sarcopenia is complex, requiring the adoption of assumptions and standards that are not well established scientifically or
clinically. A number of investigators and clinicians (both from academia and industry) met in Rome (Italy) in 2009 to develop
a consensus definition of sarcopenia. Subsequently, in Albuquerque (New Mexico, USA) in 2010, the same group met again to
consider the complex issues necessary for designing Phase II clinical trials for sarcopenia. Current clinical trial data indicate
that fat-free mass (FFM) parameters are responsive to physical activity/nutritional treatment modalities over short time periods,
but pharmacological trials of sarcopenia have yet to show significant efficacy. In order to conduct a clinical trial within
a reasonable time frame, groups that model or display accelerated aging and loss of FFM are necessary. Few studies have used
acceptable designs for testing treatment effects, sample sizes or primary outcomes that could provide interpretable findings
or effects across studies. Dual energy x-ray absorptiometry (DXA) is the measure of choice for assessing FFM, but sufficient
time is needed for changes to be detected accurately and reliably. A tool set that would allow clinical, basic and epidemiological
research on sarcopenia to advance rapidly toward diagnosis and treatment phases should be those reflecting function and strength. 相似文献
552.
WM London 《Focus on Alternative and Complementary Therapies》2011,16(3):241-242
Wiberg KR, Wiberg JMM. A retrospective study of chiropractic treatment of 276 Danish infants with infantile colic. J Manipulative Physiol Ther 2010; 33: 536–41. 相似文献
553.
Persistent fifth aortic arch was suspected by echocardiography and confirmed by magnetic resonance imaging (MRI) in an infant
with a heart murmur. Selected images including three dimensional reconstruction from MRI demonstrating this very rare congenital
anomaly are presented. 相似文献
554.
It has been widely acknowledged that permanent maglev cannot achieve stability; however, the authors have discovered that stable permanent maglev is possible under the effect of a combination of passive magnetic and nonmagnetic forces. In addition, a rotary left ventricular assist device (LVAD) with passive magnetic bearings has been developed. It is a radially driven impeller pump, having a rotor and a stator. The rotor consists of driven magnets and impeller; the motor coil and pump housing form the stator. Two passive magnetic bearings counteract the attractive force between motor coil iron core and rotor magnets; the rotor thereafter can be disaffiliated from the stator and become levitated under the action of passive magnetic and haemodynamic forces. Because of the pressure difference between the outlet and the inlet of the pump, there is a small flow passing through the gap of rotor and stator, and then entering the lower pressure area along the central hole of the rotor. This small flow comes to a full washout of all blood contacting surfaces in the motor. Moreover, a decreased Bernoulli force in the larger gap with faster flow produces a centring force that leads to stable levitation of the rotor. Resultantly, neither mechanical wear nor thrombosis will occur in the pump. The rotor position detection reveals that the precondition of levitation is a high rotating speed (over 3250 rpm) and a high flow rate (over 1?l min?1). Haemodynamic tests with porcine blood indicate that the device as a LVAD requires a rotating speed between 3500 and 4000 rpm for producing a blood flow of 4?–?6?l min?1 against 100?mmHg mean pressure head. The egg-sized device has a weight of 200?g and an O.D. of 40?mm at its largest point. 相似文献
555.
The general anatomy of avian cephalic blood vessels is well known and there are published details of their role in physiological thermoregulation. Unfortunately, the finer details of vascular pathways to and from sites of thermal exchange are not well known. Additionally, the role of the rete ophthalmicum (RO), a vascular heat exchanger in the temporal region, has been investigated in terms of brain temperature regulation, yet only the arteries have received substantial attention. Without anatomical details of both the arterial and venous pathways, the role of blood vessels in physiological thermoregulation is incomplete. Cephalic vascular anatomy of multiple avian taxa was investigated using a differential‐contrast, dual‐vascular injection technique and high‐resolution X‐ray microcomputed tomography. Sites of thermal exchange (oral, nasal, and orbital regions) and the RO were given special attention due to their known roles in cephalic thermoregulation. Blood vessels to and from sites of thermal exchange were investigated to detect conserved vascular patterns and their ability to deliver cooled blood to the RO and dural venous sinus. Sites of thermal exchange were supplied by arteries directly and through collateral pathways. Veins were found to offer multiple pathways that could influence the temperature of neurosensory tissues, as well as pathways that would bypass neurosensory tissues. These results question the paradigm that arterial blood from the RO is the primary method of brain cooling in birds. A shift in the primary role of the RO from brain cooling to regulating and maintaining the temperature of the avian eye should be further investigated. Anat Rec, 299:1461–1486, 2016. © 2016 Wiley Periodicals, Inc. 相似文献
556.
Simone SM Ho Winnie WM Yu Terence T Lao Daniel HK Chow Joanne WY Chung Yi Li 《Journal of clinical nursing》2009,18(17):2426-2435
Aims. This study aims to identify the needs, concerns and problems of pregnant women when using maternity support garments. Background. Maternity support belt is regarded as helpful in reducing low back pain during pregnancy. However, several garment‐related problems exist which might lead to poor adherence behaviour undermining the benefit of garment therapy. Design. A qualitative exploratory study. Methods. Semi‐structured interviews were conducted with 10 pregnant Chinese women who experienced low back pain during pregnancy. All the interviews followed an interview guide and different maternity support garments were shown to the participants as a method of tangible objects to stimulate responses. Content analysis was used to analyse the data. Results. The results showed that 60% of pregnant women discontinued using maternity support garments due to excessive heat, perceived ineffectiveness, itchiness, excessive pressure around the abdomen and inconvenience of adjustment. The content analysis generated five main themes of needs including effective function, safety, skin comfort, ease to put on and take off and aesthetics of maternity support garments. Discussion. The findings of the five main themes of needs were largely consistent with previous studies examining medical garments for overall satisfaction and compliance. The results revealed that women’s physiological and psychological changes during pregnancy influenced their clothing preferences on both functional and aesthetical values. Conclusions. Maternity support garments are convenient and easily‐accessible therapy to manage LBP during pregnancy and are frequently recommended and worn by pregnant women. However, inappropriate choice of garment therapy not only led to ineffectiveness but also undesirable effects. The key findings of the five main themes of garment needs in pregnant women will facilitate healthcare professionals in providing evidence‐based advice to assist patients in the selection of an appropriate and optimal maternity support garment. Relevance to clinical practice. These recommendations in the clinical practice will assist patients in making well informed treatment decisions and ultimately improve the quality of care. 相似文献
557.