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排序方式: 共有676条查询结果,搜索用时 15 毫秒
51.
Gunn S Hashimoto S Karakozov M Marx T Tan IK Thompson DR Vincent JL 《Critical care (London, England)》2004,8(4):213-218
A young person presents with a highly malignant brain tumour with hemiparesis and limited prognosis after resection. She then suffers an iatrogenic cardiac and respiratory arrest that results in profound anoxic encephalopathy. A difference in opinion between the treatment team and the parent is based on a question of futile therapy. Opinions from five intensivists from around the world explore the differences in ethical and legal issues. A Physician-ethicist comments on the various approaches. 相似文献
52.
While the Weight Efficacy Lifestyle Questionnaire (WEL) shows promise as a measure of self-efficacy for eating control, there is a lack of research examining the psychometric properties of this measure with ethnic minorities. The current study examined the WEL with a sample of 144 overweight and obese African American females. Analyses indicated similar self-efficacy levels compared to predominantly Caucasian samples. Supporting the validity of the WEL, participants undergoing obesity treatment demonstrated modest improvement in WEL scores, while standard care participants showed no changes in self-efficacy over time. Factor analysis indicated a four-factor structure rather than the five factors previously found. The four-factor structure accounted for 61.85% of the variance. Results indicate the WEL may be a valid measure of self-efficacy for overweight and obese African American women, although researchers should be mindful of the variation in scale properties when using the WEL with this population. 相似文献
53.
Responses of neurons in the ventral cochlear nucleus (VCN) of anesthetized chinchillas to six synthetic vowel sounds (/a/, /e/, /epsilon/, /i/, /o/ and /u/) were recorded at several intensity levels. Stimuli were synthesized with a fundamental frequency of 100 Hz or 181.6 Hz and had formant values at integer multiples of 100 Hz. Responses came from most neuron types in the VCN (with the exception of onset cells with an I-shaped pattern). Population studies, performed only on primary-like (PL) and chopper neurons, showed that PL neurons provide a better temporal representation than do chopper neurons. At the lowest level of stimulation, all neuron types provide an accurate rate-place representation of vowel spectra. With an increase in stimulus level, the rate-place representation of PL neurons becomes inferior to that of chopper neurons, either sustained choppers or transient choppers. 相似文献
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55.
Mary Ann Rhode Tyrrel Boehme Cynthia Tomsu Hames 《Journal of Midwifery & Women's Health》1979,24(6):33-37
Simulated learning situations using models and visual aids can provide more efficient use of available teaching time and more complete conceptualization of manual skills by nurse-midwifery students. Five inexpensive teaching aids with directions for each are presented. Further sharing of teaching aids between nurse-midwifery programs is encouraged. 相似文献
56.
The introduction of a fluorescent staining technique for identification of Y chromosome made possible the distinction of X- and Y-bearing human spermatozoa. Using this fluorescence analysis the isolation of Y- and X-bearing human spermatozoa were investigated employing two different methods for separation of spermatozoa. 1. The migration of human spermatozoa in cervical mucus obtained from women shortly before mid-cycle was studied, using an in-vitro method for horizontal sperm penetration. Basing on the progressive sperm motility in cervical mucus, a fraction rich in Y-bearing spermatozoa in the frontal zone of sperm migration was found. 2. Gradient centrifugation at different rotor speeds using a discontinous sucrose gradient has been employed for separation of human spermatozoa. A significant trend for separation of Y- and X-bearing spermatozoa was demonstrated. The results were shortly discussed. 相似文献
57.
Mette KS Larsen Trine R Thomsen Claus Moser Niels Høiby Per H Nielsen 《BMC clinical pathology》2008,8(1):10
Background
Catheters are the most common cause of nosocomial infections and are associated with increased risk of mortality, length of hospital stay and cost. Prevention of infections and fast and correct diagnosis is highly important. 相似文献58.
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