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961.
Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear.  相似文献   
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Diagnostic medical sonography has been evolving as a recognized allied health occupation since the early 1970s, but no bibliometric studies of the literature of the field have been published. This study, part of the Medical Library Association Nursing and Allied Health Resources Section's Project for Mapping the Literature of Allied Health, attempted to identify the core journals in diagnostic medical sonography and determine how well these journals are indexed by MEDLINE, EMBASE/Excerpta Medica, and the Cumulative Index to Nursing and Allied Health Literature (CINAHL). Citation analysis was done using the three journals listed for the field by the Brandon/Hill list. Characteristics of two of these three journals affected the results to the extent that more data should be gathered to reach conclusions about the literature of diagnostic medical sonography as a whole. Results of the analysis do suggest that the literature of echocardiography, which is a special area of diagnostic medical sonography, is indexed much more completely by MEDLINE and EMBASE/Excerpta Medica than by CINAHL. Suggestions are made for librarians making collection development decisions in this area of allied health.  相似文献   
969.
Atwan, Robert, Barry Orton, and Alliam Vesterman. American Mass Media: Industries and Issues (New York: Random House, 1978—$8.95, paper)

Dennis, Everette E., Arnold H. Ismach, and Donald M. Gillmor, eds. Enduring Issues in Mass Communication (St. Paul, Minn.: West P.' _fishing Co., 1978—price not given, paper)

White, David Manning, and John Pendleton, eds. Popular Culture: Mirror of American Life (Del Mar, Calif.: Publisher's Inc., 1977—$11.95/6.25)

Charlene J. Brown, Trevor R. Brown, and William L. Rivers' The Media and the People (New York: Holt, Rinehart a Winston, 1978 —price not given, paper)

Malcolm Muggeridge's Christ and the Media (Grand Rapids, Mich.: William B. Eerdmans Publishing Co., 1977— $5.95)  相似文献   
970.
Strength and power athletes are primarily interested in enhancing power relative to body weight and thus almost all undertake some form of resistance training. While athletes may periodically attempt to promote skeletal muscle hypertrophy, key nutritional issues are broader than those pertinent to hypertrophy and include an appreciation of the sports supplement industry, the strategic timing of nutrient intake to maximize fuelling and recovery objectives, plus achievement of pre-competition body mass requirements. Total energy and macronutrient intakes of strength-power athletes are generally high but intakes tend to be unremarkable when expressed relative to body mass. Greater insight into optimization of dietary intake to achieve nutrition-related goals would be achieved from assessment of nutrient distribution over the day, especially intake before, during, and after exercise. This information is not readily available on strength-power athletes and research is warranted. There is a general void of scientific investigation relating specifically to this unique group of athletes. Until this is resolved, sports nutrition recommendations for strength-power athletes should be directed at the individual athlete, focusing on their specific nutrition-related goals, with an emphasis on the nutritional support of training.  相似文献   
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