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排序方式： 共有10000条查询结果，搜索用时 31 毫秒
991.
992.
F.R.S. Powell 《Journal of The Franklin Institute》1838,26(3):187-188
993.
S. Mahadevan 《Resonance》2007,12(1):15-22
For a scientist, making a seminal contribution even in one area of science is a matter of joy and pride. To be able to start
several fields and contribute significantly to all of them is indeed a rare feat. Louis Pasteur belongs to this rare breed
of scientists. He was a chemist, microbiologist, immunologist, and biotechnologist, all rolled into one. He founded the field
of stereochemistry, established the foundations of modern microbiology, disproved the theory of spontaneous generation, demonstrated
the microbial basis of fermentation, and derived vaccines against several bacterial and viral diseases. His contributions
to human welfare in one life-time are more than what others can aspire to make over many lifetimes. His approach, based on
logic and reason, helped to shape the modern scientific outlook. 相似文献
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995.
Traditionally, it has been assumed that during middle-distance running oxygen uptake (VO2) reaches its maximal value (VO2max) providing the event is of a sufficient duration; however, this assumption is largely based on observations in individuals with a relatively low VO2max. The aim of this study was to determine whether VO2max is related to the VO2 attained (i.e. VO2peak) during middle-distance running on a treadmill. Fifteen well-trained male runners (age 23.3 +/- 3.8 years, height 1.80 +/- 0.10 m, body mass 76.9 +/- 10.6 kg) volunteered to participate in the study. The participants undertook two 800-m trials to examine the reproducibility of the VO2 response. These two trials, together with a progressive test to determine VO2max, were completed in a randomized order. Oxygen uptake was determined throughout each test using 15-s Douglas bag collections. Following the application of a 30-s rolling average, the highest VO2 during the progressive test (i.e. VO2max) was compared with the highest VO2 during the 800-m trials (i.e. VO2peak) to examine the relationship between VO2max and the VO2 attained in the 800-m trials. For the 15 runners, VO2max was 58.9 +/- 7.1 ml x kg(-1) x min(-1). Two groups were formed using a median split based on VO2max. For the high and low VO2max groups, VO2max was 65.7 +/- 3.0 and 52.4 +/- 1.8 ml x kg(-1) x min(-1) respectively. The limits of agreement (95%) for test-retest reproducibility for the VO2 attained during the 800-m trials were +/- 3.5 ml x kg(-1) x min(-1) for a VO2peak of 50.6 ml x kg(-1) x min(-1) (the mean VO2peak for the low VO2max group) and +/- 2.3 ml x kg(-1) x min(-1) for a VO2peak of 59.0 ml x kg(-1) x min(-1) (the mean VO2peak for the high VO2max group), with a bias in VO2peak between the 800-m runs (i.e. the mean difference) of 1.2 ml x kg(-1) x min(-1). The VO2peak for the 800-m runs was 54.8 +/- 4.9 ml x kg(-1) x min(-1) for all 15 runners. For the high and low VO2max groups, VO2peak was 59.0 +/- 3.3 ml x kg(-1) x min(-1) (i.e. 90% VO2max) and 50.6 +/- 2.0 ml x kg(-1) x min(-1) (i.e. 97% VO2max) respectively. The negative relationship (-0.77) between VO2max and % VO2max attained for all 15 runners was significant (P = 0.001). These results demonstrate that (i) reproducibility is good and (ii) that VO2max is related to the %VO2max achieved, with participants with a higher VO2max achieving a lower %VO2max in an 800-m trial on a treadmill. 相似文献
996.
This study analyzes the search behavior of end users who had taken a class in searching MEDLINE on the National Library of Medicine's MEDLARS system. Of the class alumni, 58% obtained passwords. Most of these were still conducting their own searches twelve to eighteen months later. Telephone interviews and search observations indicated that these end users were satisfied with their results and felt they had mastered the basic mechanics of searching. However, appropriate use of explodes and subheadings, as well as locating appropriate search terms, still presented difficulties for them. Further training in these areas may be required. 相似文献
997.
998.
999.
Evolution of an end-user training program 总被引：1，自引：0，他引：1
The University of Illinois at Chicago Library of the Health Sciences has taught end-user classes on the MEDLARS system since early 1985. Registration, class composition, and, most importantly, class organization evolved continuously during the first year of operation. Several feedback mechanisms were used. An examination of the past training and specialization of participants helped to determine teaching examples and pace; a more varied group of participants necessitated a broader range of examples and increased explanations. Participant evaluation forms and oral comments helped define scheduling, agenda, and the need for additional equipment and practice time. Further evaluation will center on the searching done by the program's alumni. 相似文献
1000.