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151.
A Bashey S Shepherd W Frankel J Wang-Rodriguez T Cahill M Chamberlain JR Mason AD Ho RE Corringham 《Canadian Metallurgical Quarterly》1998,5(1):281-285
A suspension culture of white lupin cells has been established, and proteins of the exocellular matrix analysed. Based on homologies of N-terminal amino-acid sequences, three stress- or defence-related proteins: acidic class III chitinase, polygalacturonase-inhibiting protein, and germin/oxalate oxidase, secreted by lupin cell culture, were identified. 相似文献
152.
The current adjustment of cochlear implant (CI) speech processors is based on a knowledge of the lower and upper limits (T- and C-levels) for electrical stimulus currents. These data are usually acquired from subjective classifications of individual patients. In cases with non-reliable patient responses, objective methods are necessary. Especially for the estimation of correct T-levels, auditory evoked potentials (AEP) can be applied, since they allow the determination of response thresholds in a frequency-specific manner. By determining the AEP of different latencies, late cortical responses can be registered almost without artifact contamination. These patients have been examined in 20 patients provided with 22- or 8-channel CI-systems (Nucleus or Med-EI implants). In all cases, clear responses and clearly discernible threshold transitions could be detected. By making use of acoustical stimulation in a free sound field, subjective hearing threshold and the T-levels of electrical stimulation could be verified. Since late responses are generated in the primary auditory cortex, their assessment permits a nearly integral functional control of the aided hearing system. To date, no problems have occurred from maturation or attentional effects in either pediatric or adult patients. The applicability in very young children remains to be explored. 相似文献
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154.
Biorobotics is a promising new area of research at the interface between biology and robotics. Robots can either be used as physical models of biological systems or be directly inspired by biological studies. A great deal of progress has recently been made in biorobotic studies of locomotion, orientation, and vertebrate arm control. 相似文献
155.
RE Wood 《Canadian Metallurgical Quarterly》1996,6(2):237-251
Endoscopic techniques for evaluation and management of airway and pulmonary problems in pediatric patients have matured greatly in the past decade, especially with the introduction of flexible instruments suitable for use in the smallest infants. Careful selection of the most appropriate instrument and technique by well-trained medical or surgical endoscopists will result in safe and effective diagnosis and treatment of a wide variety of conditions affecting the upper and lower respiratory tract. 相似文献
156.
MA Pereira AM Kriska RD Day JA Cauley RE LaPorte LH Kuller 《Canadian Metallurgical Quarterly》1998,158(15):1695-1701
BACKGROUND: It is important to determine if permanent lifestyle changes may result from physical activity interventions and whether health may be affected by these changes. OBJECTIVE: To conduct a 10-year follow-up of physical activity and self-reported health status in participants of a randomized clinical trial of walking intervention. METHODS: Of the original 229 volunteer postmenopausal women who participated in the original clinical trial, 196 (N = 96 intervention and 100 controls) completed the 10-year follow-up telephone interview. The interview protocol included questions on self-reported walking for exercise and purposes other than exercise, the Paffenbarger sport and exercise index, functional status, and various chronic diseases and conditions. RESULTS: The median values for both usual walking for exercise and total walking were significantly higher for walkers compared with controls (for both, P = .01), with median differences of 706 and 420 kcal/wk, respectively. After excluding women who reported heart disease during the original trial, 2 women in the walking group (2%) and 11 women in the control group (12%) reported physician-diagnosed heart disease over the last 10 years (P = .07). There were also fewer hospitalizations, surgeries, and falls among women in the walking group, although these differences were not statistically significant (P>.05). CONCLUSIONS: Although limited by self-report, this study may be the first to demonstrate long-term exercise compliance to a randomized control trial in older women and to suggest that health benefits may have ensued as a result of these increased activity levels. 相似文献
157.
BA Hart J Bauer HJ Muller B Melchers K Nicolay H Brok RE Bontrop H Lassmann L Massacesi 《Canadian Metallurgical Quarterly》1998,153(2):649-663
N-methyl-D-aspartate (NMDA) and non-NMDA receptor-mediated manipulations of the cortical cholinergic input arising from the basal forebrain differentially affect cognitive function. We used [14C]-2-deoxyglucose autoradiography in conscious rats to map the effects of excitatory amino acid agonist infusions into the nucleus basalis magnocellularis (NBM) on cerebral functional activity, as reflected by local rates of glucose utilization. Acute stimulation of NBM neurones by local infusion of alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), 15 min before glucose use measurement, resulted in glucose use reductions in nine cortical regions innervated by NBM efferents including prefrontal, frontal, sensorimotor and cingulate cortices. NMDA infusions altered glucose use in two cortical areas. Both AMPA and NMDA markedly increased glucose use in the striatum and globus pallidus, with concomitant perturbations in striato-pallidal projection targets including the substantia nigra, entopeduncular nucleus, subthalamic nucleus and lateral habenular nucleus. In contrast, the GABAA agonist muscimol did not affect glucose use in the NBM or neocortical regions, but induced glucose use increases in several subcortical nuclei including the substantia nigra and entopeduncular nucleus. The delayed effects of excitotoxic lesions were assessed 3 weeks after basal forebrain infusions of AMPA, NMDA, ibotenate or quisqualate. Statistically significant glucose use changes only occurred in the hypothalamus after NMDA, and the NBM after ibotenate infusions, although reduced cortical metabolism was apparent following AMPA-induced lesions of the NBM. Results support a dissociation between the functional sequelae of NMDA and non-NMDA receptor-mediated events in the basal forebrain, and long-term compensatory functional adaptation following cortical denervation. 相似文献
158.
Earlier studies have shown that coenzyme A (CoA) protects against cisplatin (CP) induced deafness in guinea pigs. We studied the correlation between the latency of the N1 wave in electrocochleography and total loss of cilia in hair cells by scanning electron microscopy. 相似文献
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160.