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Studies on the development of automatic postural responses in both typically developing children and children with cerebral palsy were performed. With the appearance of "pull-to-stand" behavior, typically developing children first began to show muscle responses to platform movements in mainly the ankle muscles. With increased development, additional agonist muscles were added to the response pattern and a consistent distal to proximal sequence began to emerge. Well-organized responses were seen with the onset of independent stance and walking, along with the reduction of antagonist muscle co-activation. The older children with cerebral palsy who were pre-walkers had immature muscle activation patterns like those seen in the typically developing children at the pull-to- stand stage of development. These included disorganized muscle responses and increased frequency of coactivation of both proximal–distal and agonist–antagonist muscles. In order to determine if musculoskeletal constraints contributed to these response patterns, normal children were asked to stand in a crouched posture similar to that of children with CP. This caused postural muscle response patterns to more closely approximate those of children with spastic diplegia.  相似文献   
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51 patients who were selected for aorto-bifemoral bypass operation (infrarenal aortic aneurysm, iliac or iliofemoral occlusive disease) were randomized into two groups. 26 patients were operated on under neuroleptanaesthesia and 25 patients had a continuous thoracic epidural, which was supplemented with a light general anaesthesia during the operation. All patients were optimally volume loaded prior to surgery. The most marked haemodynamic alterations (tachycardia, arterial hypertension, increase of cardiac index, left ventricular stroke work index and cardiac minute work) were provoked by eventration of the gut. In the epidural group, these changes were attenuated and in contrast to the neuroleptanaesthesia group, there were a few patients who had a serious fall in blood pressure. These reactions were regularly accompanied by a generalized flush which led to the hypothesis that they were caused by the release of intestinal hormones, reactive peptides and neurotransmitters, from the mechanically irritated gut. Clamping of the aorta was relatively uneventful. Heart rate and cardiac index decreased in both groups but mean arterial pressure and pulmonary capillary wedge pressure remained stable. Systemic vascular resistance increased slightly in the neuroleptanaesthesia, but not in the epidural group. Declamping was followed by significant but transient falls in systemic vascular resistance and arterial pressure in both groups, despite sufficient volume loading before opening the clamp. In the neuroleptanaesthesia group these changes spontaneously returned to normal; in the epidural group 6 patients received vasopressors or positive inotropic drugs. These results indicate the following: Epidural anaesthesia prevents hypertension and tachycardia and lowers cardiac minute work. Eventration of the gut, acute blood losses and declamping of the aorta may be critical situations, which can lead to profound hypotension. Under neuroleptanaesthesia eventration of the gut is followed by tachycardia and hypertension whereas blood losses and declamping are not as critical as when an epidural is used. Only experienced anaesthetists should use epidural anaesthesia for aortic surgery. An intensive monitoring of haemodynamic function during this form of anaesthesia is mandatory.  相似文献   
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Facial burns are very common and have significant clinical impact. However, the treatment regimen for superficial to deep facial burns is not well defined. The purpose of this study was to investigate the effects of cadaver skin grafting in deep partial thickness facial burns in comparison to standard care. In a prospective open study design severely injured patients with superficial and deep partial thickness burns were randomized into the group receiving open treatment with silversulfadiazine (standard n=5) or into the group receiving early superficial debridement followed by coverage with glycerolized cadaver skin (n=5). The outcome measures were time and quality of wound healing, and incidence of hypertrophic scarring at 3 and 6 months post burn. There were no significant differences in demographics between groups. In the group treated with the allogenic material time to reepithelialization was 10.5 days, while it was 12.4 days in the silversulfadiazine group (p<0.05). Scar quality was found to be significantly improved in the allogenic treatment group. Three and 6 months postburn there were no patients with significant hypertrophic scarring in the allogenic group while there were two patients who developed hypertrophic scars in the silversulfadiazine group (p<0.05). In this study, we demonstrated that glyzerolized cadaver allograft skin represents a superior biological dressing for shallow and deep partial thickness facial burns. This is in concordance with other reports on scalds. It would be worthwhile to perform more clinical studies with a larger number of patients to further evaluate the effect and function of allogenic skin for facial burns.  相似文献   
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Exocytosis of neurotransmitter from synaptic vesicles is restricted to specialized sites of the presynaptic plasma membrane called active zones. A complex cytomatrix of proteins exclusively assembled at active zones, the CAZ, is thought to form a molecular scaffold that organizes neurotransmitter release sites. Here, we have analyzed synaptic targeting and cytomatrix association of Bassoon, a major scaffolding protein of the CAZ. By combining immunocytochemistry and transfection of cultured hippocampal neurons, we show that the central portion of Bassoon is crucially involved in synaptic targeting and CAZ association. An N-terminal region harbors a distinct capacity for N-myristoylation-dependent targeting to synaptic vesicle clusters, but is not incorporated into the CAZ. Our data provide the first experimental evidence for the existence of distinct functional regions in Bassoon and suggest that a centrally located CAZ targeting function may be complemented by an N-terminal capacity for targeting to membrane-bounded synaptic organelles.  相似文献   
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Background--Currently, the reporting and archiving of echocardiographic data suffer from the difficulty of representing heart motion on printable 2-dimensional (2D) media. Methods and Results--We studied the capability of holography to integrate motion into 2D echocardiographic prints. Images of normal human hearts and of a variety of mitral valve function abnormalities (mitral valve prolapse, systolic anterior motion of the mitral leaflets, and obstruction of the mitral valve by a myxoma) were acquired digitally on standard echocardiographic machines. Images were processed into a data format suitable for holographic printing. Angularly multiplexed holograms were then printed on a prototype holographic "laser" printer, with integration of time in vertical parallax, so that heart motion became visible when the hologram was tilted up and down. The resulting holograms displayed the anatomy with the same resolution as the original acquisition and allowed detailed study of valve motion with side-by-side comparison of normal and abnormal findings. Comparison of standard echocardiographic measurements in original echo frames and corresponding hologram views showed an excellent correlation of both methods (P<0.0001, r2=0.979, mean bias=2.76 mm). In this feasibility study, both 2D and 3D holographic images were produced. The equipment needed to view these holograms consists of only a simple point-light source. Conclusions--Holographic representation of myocardial and valve motion from echocardiographic data is feasible and allows the printing on a 2D medium of the complete heart cycle. Combined with the recent development of online holographic printing, this novel technique has the potential to improve reporting, visualization, and archiving of echocardiographic imaging.  相似文献   
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2.3核磁共振血管成像(MRA) 2.3.1背景和方法:在头部MRI检查中常结合MRA,用于急性卒中患者病情评估以指导治疗决策的制定^[19]。日前,有几种不同的MRA技术用于脑血管成像,包括二维时间飞跃(timeof-flight,TOF)序列、三维TOF序列、  相似文献   
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