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This paper introduces the design and implementation of a generic wireless and Real-time Multi-purpose Health Care Telemedicine system applying Bluetooth protocol, Global System for Mobile Communications (GSM) and General Packet Radio Service (GPRS). The paper explores the factors that should be considered when evaluating different technologies for application in telemedicine system. The design and implementation of an embedded wireless communication platform utilising Bluetooth protocol is described, and the implementation problems and limitations are investigated. The system is tested and its telecommunication general aspects are verified. The results showed that the system has (97.9 +/- 1.3)% Up-time, 2.5 x 10(-5) Bit Error Rate, 1% Dropped Call Rate, 97.4% Call Success Rate, 5 second transmission delay in average, (3.42 +/- 0.11) kbps throughput, and the system may have application in electrocardiography. 相似文献
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Tetsurou Torisu Kelun Wang Peter Svensson Antoon De Laat Hiroyuki Fujii Lars Arendt-Nielsen 《Clinical neurophysiology》2007,118(5):999-1009
OBJECTIVE: To investigate the effects of muscle fatigue induced by low-level isometric jaw-clenching and subsequent glutamate-evoked muscle pain on the exteroceptive suppression (ES) response and resting electromyographic (EMG) activities in human jaw muscles. METHODS: The resting EMG activity and the ESs were recorded before (baseline), after low-level jaw-clenching (Post1), after subsequent glutamate or isotonic saline injections into the left masseter (Post2), and 60 min after the clenching (Post3) in 23 healthy volunteers. RESULTS: The late ES (ES2) showed more inhibition at Post1 compared with baseline (P<0.05). It was less inhibited after both types of injections (Post2), and increased at Post3 again (P<0.05) with no significant difference between the glutamate and isotonic saline sessions. The resting EMG activity increased at Post1 and Post2 (P<0.05). The glutamate injection further increased the resting EMG activity in the injected muscle (P<0.01). CONCLUSIONS: Muscle fatigue influences inhibitory reflex pathways in jaw-closing muscles and subsequent acute muscle pain potentiates the local increase in the resting EMG activity of the painful muscle. SIGNIFICANCE: Muscle fatigue which can be observed in patients with oral dysfunctions may interact with nociceptive regulation and influence the clinical presentation of jaw symptoms and function. 相似文献
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Neural classifier construction using regularization, pruning and test error estimation 总被引:1,自引:0,他引:1
Mads Hintz-Madsen Lars Kai Hansen Jan Larsen Morten With Pedersen Michael Larsen 《Neural networks》1998,11(9):1659-1670
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems. 相似文献
48.
Viktoria Werkström Lars Ny Katarina Persson K.-E. Andersson 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):151-158
Neuronal regulation of smooth muscle tone in the female pig urethra has mainly been studied in vitro using electrical field
stimulation (EFS) of nerves. Excitatory control is considered to be exerted by released noradrenaline, whereas inhibitory
control is non-adrenergic non-cholinergic (NANC), and mediated by nitric oxide (NO), and an as yet unidentified agent. We
investigated the functional and morphological effects of α-latrotoxin (αLTX), a spider neurotoxin believed to cause massive
release of vesicle-stored neurotransmitters, on spontaneously developed urethral smooth muscle tone. The effects were compared
to those of EFS and high potassium. In the presence of the NO-synthesis inhibitor Nω-nitro-L-arginine (L-NOARG: 0.3 mM) both αLTX and EFS evoked contractions. After treatment with scopolamine and phentolamine,
no contraction was observed, and under these conditions αLTX and EFS induced relaxation. At low frequencies (<12 Hz), the
EFS-induced relaxations were rapid, whereas at higher frequencies (>12 Hz), they were biphasic, consisting of a rapid first
phase followed by a more long-lasting second phase. L-NOARG abolished the relaxations at low frequencies, as well as the first
phase of the biphasic relaxation. The second phase was not affected by treatment with L-NOARG, but 0.1 μM ω-conotoxin GVIA,
blocker of N-type voltage-operated calcium- channels (VOCCs), markedly reduced or abolished the response. In the presence
of L-NOARG or ω-conotoxin GVIA, the αLTX-induced relaxation was significantly decreased, and the combination of L-NOARG and
ω-conotoxin GVIA further reduced or abolished the relaxation. In preparationstreated with tetrodotoxin or scorpion venom,
believed to inactivate nerves by acting on sodium channels, αLTX and EFS had no effects. αLTX-induced relaxation was not associated
with changes in cyclic GMP or cyclic AMP content. High (80 mM) potassium solution induced a triphasic response of the preparation.
A transient relaxation was followed by a restoration of tone, and then by a persistent relaxation. The persistent relaxation
was slightly reduced by scorpion venom or L-NOARG, but reduced by 50% by a combination of L-NOARG and ω-conotoxin GVIA. Ultrastructural
analysis of the urethral circular smooth muscle layer revealed a moderate amount of nerve profiles supplying the smooth muscle.
In control preparations, the nerve profiles contained both small synaptic vesicles and large dense core vesicles. αLTX caused
a major loss of both types of vesicle. The present data suggest that αLTX has the ability to release not only adrenergic and
cholinergic transmitters, but also NANC mediators of relaxation, including NO, from nerve terminals in the urethra.
Received: 13 January 1997 / Accepted: 17 April 1997 相似文献
49.
Successful internal arterial embolization with steel coils in life-threatening bleeding after femoral fracture is described in an older patient. 相似文献
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