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排序方式: 共有10000条查询结果,搜索用时 218 毫秒
991.
992.
A C Da Rosa B Kemp T Paiva F H Lopes da Silva H A Kamphuisen 《Electroencephalography and clinical neurophysiology》1991,78(1):71-79
A model of sleep phasic events such as vertex waves, K complexes, delta waves and sleep spindles is proposed. It consists of feedback loops that are driven by white noise (simulating tonic delta and sigma activity) and by isolated random impulses, simulating vertex waves or K complexes, depending on the background tonic activity. A model-based method for the detection of sleep phasic events was implemented in a personal computer. Its performance was investigated using simulated and real whole-night EEG signals. The method was able to detect K complexes and vertex waves in a reliable way in spite of their variable shapes and in the presence of a variety of background activities. The detector appears to have superior performance to those so far reported in the literature. The performance of the detector was also compared to that of an electroencephalographer using normal sleep EEG records of 8 h duration from 6 subjects. The performance was satisfactory both in terms of accuracy and reliability. The problem of detecting K complexes in stages 3 and 4 of sleep is discussed. 相似文献
993.
Eleven white male right handed violin players complained of transient muscular deficit of the extensor compartment of the left forearm during and after prolonged playing. This was associated with paraesthesiae and pain. Relief was achieved keeping the wrist and the elbow flexed, with the supinated forearm held by the contralateral hand. An anatomical study showed changes of the relationship of the posterior interosseous nerve with its surrounding structures with pronation and supination of the forearm. On the basis of the clinical features, the anatomical studies and the response to a simple physiotherapeutic regime, it is suggested that prolonged pronation of the forearm may cause transient entrapment of the nerve. 相似文献
994.
K S McGrew R F Ittenbach R H Bruininks B K Hill 《Research in developmental disabilities》1991,12(2):181-199
Data obtained on a sample of persons with mild to profound degrees of mental retardation (N = 8255) and ranging from birth to 98 years of age were factor analyzed to provide information on the structure of maladaptive behavior relative to age and degree of mental retardation. Using the Problem Behavior scales of the Inventory for Client and Agency Planning, two principal factors emerged for children with mild to profound degrees of retardation: Internalized Maladaptive and Externalized Maladaptive. For adolescents and young adults, a three-factor solution which varied by degree of retardation was most appropriate. For middle and older adults, three- and four-factor solutions were identified across all ages and degrees of retardation. Across all samples as many as six different types of dimensions were identified, indicating that the structure of maladaptive behavior may well be influenced by age and level of mental retardation. 相似文献
995.
The Mauthner cell (M-cell) of the ‘weakly electric fish’ Gymnotus carapo was investigated with electrophysiological techniques. The antidromic action potential, the recurrent inhibitory input and the posterior VIIIth nerve excitatory input in this cell exhibited characteristics similar to those described in the goldfish. In addition, we found an excitatory input evoked by spinal stimulation at intensities subthreshold for M-cell axons. 相似文献
996.
997.
998.
P. Priego E. Lobo G. Rodríguez J. Cabañas J. Pérez de Oteyza V. Fresneda 《Clinical & translational oncology》2007,9(2):106-109
Abstract
Background and study aims: The advent of endoscopic techniques in the last decades has produced a change in the approach of the oesophageal leiomyoma.
The aim of the study is to explain our experience in the laparoscopic surgery of the oesophageal leiomyoma.
Materials and methods: We realised a retrospective study of the oesophageal leiomyoma operated on in our centre by the endoscopic approach between
2001 and 2004. There were two females and two males. All were symptomatic and pyrosis was the most frequent symptom. The preoperative
study was an oral endoscopy and barium swallow. In all the cases enucleation was performed, two by thoracoscopy and two by
laparoscopy approach.
Results: The mean operating time was 230 min. No deaths or intraoperative complications occurred and there were no cases of conversion
to open surgery either. The mean postoperative hospital stay was 3.25 days (range 2–4 days). There was no case of recurrence.
Conclusions: The enucleation is an easier procedure and constitutes the therapy of choice of the oesophageal leiomyoma. We think that muscle
borders should be closed after enucleation and that biopsy is not indicated preoperatively. 相似文献
999.
Teriparatide vs. calcitonin in the treatment of Asian postmenopausal women with established osteoporosis 总被引:4,自引:0,他引:4
J. S. Hwang S. T. Tu T. S. Yang J. F. Chen C. J. Wang K. S. Tsai 《Osteoporosis international》2006,17(3):373-378
This study compared the clinical efficacy, safety, and tolerability of daily subcutaneous injections of teriparatide and salmon
calcitonin in the treatment of postmenopausal women with established osteoporosis in Taiwan. This 6-month, multicenter, randomized,
controlled study enrolled 63 women with established osteoporosis. They were randomized to receive either teriparatide 20 μg
or calcitonin 100 IU daily in an open-label fashion. Lumber spine, femoral neck, total hip bone mineral density (BMD), and
biochemical markers of bone turnover were measured, and adverse events and tolerability were recorded. The results at 6 months
showed that patients using teriparatide had larger mean increases in spinal BMD than those who used calcitonin (4.5% vs. 0.1%),
but the BMD changes in these two groups at the femoral neck and the total hip were not significant. There were also larger
mean increases in bone markers in the teriparatide group than in the calcitonin group (bone specific alkaline phosphatase
142% vs. 37%; osteocalcin 154% vs. 23%). We conclude that teriparatide has more positive effects on bone formation than salmon
calcitonin, as shown by the larger increments of lumbar spine BMD and bone formation markers, and caused only mild adverse
events and no significant change in liver, kidney or hematological parameters. Compared with the published global results,
teriparatide seems to be equally effective and safe to use in this Asian population. 相似文献
1000.
F. Madsen 《Clinical and experimental allergy》2006,36(6):850-851