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31.
The present study describes food habits in adolescents in thirty-five countries and regions (European countries/regions, Israel, Canada and the USA), based on the food-frequency questions from the cross-sectional Health Behaviour in School-aged Children survey of the year 2001-2. A total of 162,305 pupils of 11, 13 or 15 years of age completed an anonymous standardised questionnaire on health and lifestyle factors during one school hour. Large differences in food habits between countries were found: the consumption frequency of fruit varied from on average 2.8 to 5 d/week, the consumption of vegetables varied from on average 2.4 to 5.5 d/week, the consumption of soft drinks varied from 2.1 to 5 d/week and sweet consumption from 2.6 to 5 d/week. Methodological problems in comparing between countries are discussed. Nonetheless, the results indicate a need for national and international health promotion programmes to improve adolescents' food habits. 相似文献
32.
Virosome-based active immunization targets soluble amyloid species rather than plaques in a transgenic mouse model of Alzheimer’s disease 总被引:1,自引:0,他引:1
Zurbriggen R Amacker M Kammer AR Westerfeld N Borghgraef P Van Leuven F Van der Auwera I Wera S 《Journal of molecular neuroscience : MN》2005,27(2):157-166
Active vaccination with amyloid peptides shows promise for the treatment and prevention of Alzheimer's disease (AD). Several studies in transgenic mouse models of AD have revealed the potency of vaccination to prevent or even clear amyloid plaques from mouse brain. However, the idea that soluble oligomeric species of beta-amyloid (Abeta), rather than plaques, trigger the disease has gained momentum, and current active vaccination strategies affect the levels of total or soluble brain Abeta little or not at all. We describe an active vaccination method based on Abeta1-16 presented on the surface of virosomes, which triggered a dramatic decrease in both soluble Abeta40 (75% reduction; p=0.01) and soluble Abeta42 (62% reduction; p=0.03) in a double transgenic mouse model of AD. Whereas Abeta40 and Abeta42 levels in the insoluble fraction tended to be reduced (by 30% and 27%, respectively), the number of thioflavine-S-positive amyloid plaques was not affected. The high specific antibody responses, obtained without eliciting T-cell reactivity, demonstrate that immunostimulating reconstituted influenza virosomes are a promising antigen carrier system against the neuropathology of AD. 相似文献
33.
De Maeseneer M Marcelis S Osteaux M Jager T Machiels F Van Roy P 《AJR. American journal of roentgenology》2005,184(1):175-179
OBJECTIVE: The objectives of our study were to report our initial clinical experience with sonography of the wrist for diagnosing a proximal rupture of the tendon of the extensor pollicis longus (EPL) muscle and to perform sonographic-anatomic correlation of the EPL tendon. MATERIALS AND METHODS: Clinical and imaging files of five patients who underwent sonography and subsequent open wrist surgery were reviewed retrospectively. Imaging was performed by four radiologists experienced in musculoskeletal sonography. Tendon retraction was evaluated on sonography and at surgery. In cadavers, sonography was performed in concert by two musculoskeletal radiologists during progressive stages of dissection of four embalmed specimens. One specimen was sliced in the transverse plane. RESULTS: In cadavers, the EPL tendon was located on or adjacent to Lister's tubercle and extended to the base of the thumb. The EPL tendon crossed over the extensor carpi radialis tendons where it exhibited a flattened aspect. In the five patients in the study, a tubular-shaped hypoechoic area was evident at the position of the ruptured EPL tendon on sonograms. At surgery, this area corresponded to fluid, hemorrhage, and scar tissue in the EPL tendon sheath. The assessment of tendon retraction on sonography correlated with findings at surgery. CONCLUSION: Sonography may aid in diagnosing a rupture of the EPL tendon and in the preoperative assessment of gap size and position of the retracted tendon ends. A characteristic tubular hypoechoic area may be seen crossing over the extensor carpi radialis tendons. 相似文献
34.
OBJECTIVE: Typically, symmetrical charge-balanced biphasic current pulses are used in cochlear implants to ensure biological safety. Theoretically, monophasic pulses are more effective, but potentially noxious, stimuli. In this study we charge-balanced such monophasic pulses during selected non-stimulated intervals, effectively leading to triphasic pulses with a 4:1 amplitude ratio between the cathodic and anodic phases. Apart from ensuring safety, this is also expected to reduce power consumption and channel interaction. MATERIAL AND METHODS: Seven experienced Clarion CII cochlear implant users with a multichannel (12-16 channels) monopolar continuous interleaved sampling (CIS) strategy participated in the study. Three different CIS strategies were fitted using the Clarion Research Interface (CRI-2). The reference was an implementation of each subject's own CIS program. The two strategies tested used triphasic pulses on the same channels, one with half-wave rectification (TP-HWR) and one without rectification (TP-NoR) at the input. Directly after fitting (i.e. without any training), speech perception (phoneme score on consonant-vowel-consonant words) was measured in silence (sound-only) and in speech-shaped background noise with signal:noise ratios (SNRs) of +5 and 0 dB. RESULTS: Speech perception with the reference via the CRI-2 was equal to that of the free-field condition with the subjects' own speech processor. With the TP-NoR strategy, speech perception improved significantly (from 89% to 93%) in silence and in the 0-dB SNR condition (from 43% to 49%). With a SNR of +5 dB, performance was stable at approximately 66%. With the TP-HWR strategy, performance increased significantly in the 0- and +5-dB SNR conditions, to 55% and 74%, respectively. Power consumption was reduced in both strategies, to 30% and 36% for TP-HWR and TP-NoR, respectively. CONCLUSION: The new triphasic strategies are most promising, with respect to both their improved speech perception and reduced power requirements. The optimal parameters will have to be identified following long-term use. 相似文献
35.
The authors report two cases of isolated, undisplaced, fractures of the trapezoid bone. Because of its well-protected position in the wrist, traumatic lesions of the trapezoid bone are rare. Dislocation of the trapezoid has been reported in 30 patients; fractures are seen even less frequently and usually go with dorsal displacement. To our knowledge and based on a Medline literature review, only two cases of acute and isolated, undisplaced or minimally displaced fractures of the trapezoid have been previously described. We believe that the lesion has often been missed in the past and modern diagnostic tools will make its diagnosis far more frequent. 相似文献
36.
Joren Callaert Stefaan Nijs Peter Reynders Paul Vanderschot Paul Broos 《European Journal of Trauma》2004,30(4):255-258
Abstract
Background:
The treatment of impending pathological fractures and symptomatic metastases involving the upper extremity articulations remains a challenge for the trauma surgeon. While the goals of treatment of bony metastases are clearly defined (early restoration of function, excellent pain control and minimal surgical trauma), these are not always easy to realize in upper extremity periarticular metastases.
Case Study:
A patient with a metastasis of a mediastinal nerve sheet tumor, involving the proximal 12 cm of the right humerus, including the whole head and both the tubercles, is described. A complete resection up to the level of the deltoid insertion was performed. In order to restore maximal function, the shoulder joint was reconstructed using a reversed total shoulder prosthesis. A fresh frozen cadaver proximal humerus was used as an allograft to obtain a secure stabilization of the prosthesis. Short-term results were very promising with restoration of ADL (activities of daily living) functionality within 3 months. Abduction and elevation > 100°, exorotation up to 20° and gluteal endorotation could be performed at that time.
Conclusion:
To the authors knowledge, this report is the first to describe reconstruction of the shoulder joint using a reversed shoulder prosthesis-allograft construction in case of a resection for malignancy. 相似文献
37.
A New Microphotolysis Based Approach for Mapping the Mobility of Drugs in Microscopic Drug Delivery Devices 总被引:1,自引:0,他引:1
De Smedt Stefaan C. Meyvis Tom K. L. Van Oostveldt Patrick Demeester Joseph 《Pharmaceutical research》1999,16(10):1639-1642
Pharmaceutical Research - 相似文献
38.
Cationic Polymer Based Gene Delivery Systems 总被引:19,自引:5,他引:19
Gene transfer to humans requires carriers for the plasmid DNA which canefficiently and safely carrythe gene into the nucleus of the desired cells. A series of chemically differentcationic polymers arecurrently being investigated for these purposes. Although many cationic polymersindeed condense DNAspontaneously, which is a requirement for gene transfer in most types of cells,the physicochemical andbiopharmaceutical behavior of the current generation of polyplexes severelylimits an efficient genetransfer in vitro and especially in vivo. This papersummarizes recent physicochemical and biologicalinformation on polyplexes and aims to provide new insights with respect to thistype of gene deliverysystem. Firstly, the chemical structure of frequently studied cationic polymersis represented. Secondly,the parameters influencing condensation of DNA by cationic polymers aredescribed. Thirdly, the surfaceproperties, solubility, aggregration behavior, degradation and dissociation ofpolyplexes are considered.The review ends by describing the in vitro and in vivo genetransfection behavior of polyplexes. 相似文献
39.
Carla Truyers Eliane Kellen Marc Arbyn Leen Trommelmans Herman Nys Karen Hensen Bert Aertgeerts Stefaan Bartholomeeusen Mats Hansson Frank Buntinx 《Medicine, health care, and philosophy》2010,13(2):169-175
This paper discusses the legal implications of setting up two new biobanks in Belgium. The first is hospital-based and will
archive tissue from patients with haematologic cancer, whereas the second is linked to a general practice based morbidity
registry and will involve storage of blood samples. To date, Belgium has no specific legislation that regulates storage of
human tissue and related databases. Several issues concerning the protection of individuals with regard to the processing
of personal medical data are discussed from the existing privacy legislation. We will address the principle of consent (broad
versus specific) and the type of data recorded (anonymous, encoded and identifiable) for both biobanks. 相似文献
40.
Considerable uncertainties are associated with the transfer of Tc from soil to plant. Mathematical models built to simulate that transfer generally use a single value derived from short-term experiments. Recent observations have, however, given a clear indication that the soil-to-plant transfer varies with time, depending on the biogeochemical cycling of this element. The long-term behavior of Tc in soils accidentally contaminated has been studied for 4 y in lysimeters exposed to natural climatic conditions. An important fraction of the deposit (70%) is rapidly removed from the 20-cm plow layer with a half-time of 54 +/- 2 d; the remaining fraction tends to persist in the soil for long periods of time (half-time = 30 +/- 16 y). Immediately after the deposit, the plant-to-soil concentration ratios are very high (about 400); they decrease to six 3 y after the contamination. The shape of the evolution of the contamination measured in grass after an accidental deposit is best-fitted to a sum of two exponential functions; the environmental half-times estimated for the two components are about 30 d and 2 to 3 y, respectively. 相似文献