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111.
Milk yield, parity, and cow potential as variables for computerized concentrate supplementation strategy 总被引:1,自引:0,他引:1
A trial was conducted in a dairy of a cooperating kibbutz to investigate the cow's response to individual concentrate supplementation according to daily milk production when a feed mixture containing a 50:50 concentrate:forage offered in the bunk free choice. Concentrate supplementation was provided by computerized self-feeders for cows producing over 30 kg milk/d to a maximum of 10 kg/d concentrate (as fed) according to milk production. The results were compared with those cows fed, for ad libitum intake, a total ration of 73:27 concentrate: forage (high control) and 50:50 (low control). The performance variables of individually supplemented cows (milk yield, 4% FCM yield, and BW) were analyzed according to parity and milk yield potential. The results indicated that milk yield itself could not serve as the only variable for individual concentrate supplementation as applied in this experiment. Cows in different parities and with different milk yield potentials may respond differently to the concentrate supplementation strategy, and parity numbers, milk yield potential, and BW, in addition to daily milk yield, are possible variables to be considered when applying this feeding regimen in order to exploit its economic potential efficiently. 相似文献
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Effects of the addition of a proteinase (Neutrase 1-5S) and a peptidase (aminopeptidase DP-102) as agents for accelerating the ripening of Cheddar cheese on the survival of some non-starter bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli and a Salmonella sp.) were studied throughout a 4-month ripening period. The enzymes were found to have no significant effect on the survival of the Gram-positive bacteria but some significant effects were observed, at some stages of the ripening period, with the Gram-negative bacteria in that lower levels were recovered from cheeses treated with the enzyme system. 相似文献
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During July and August 1975 a large number of patients at the Ann Arbor Veterans Administration Hospital experienced unexplained respiratory arrests, and there were six deaths. These were later shown to be due to the deliberate injection of pancuronium bromide, a muscle relaxant. A questionnaire survey of the reactions of the hospital patients and staff to the deaths revealed that the patients had more confidence in the hospital and their medical treatment than did the staff, and those patients who were theoretically most vulnerable used denial to cope with the unprecedented and frightening situation. 相似文献
116.
MS Aldrich JE Shipley R Tandon PD Kroll KJ Brower 《Canadian Metallurgical Quarterly》1993,17(6):1179-1183
Sleep apnea and related disorders are not uncommon in abstinent alcoholics. We assessed the relationship between age and the presence and severity of sleep-disordered breathing in alcoholism by performing one night of polysomnography on 75 abstinent alcoholic subjects undergoing treatment for alcoholism. Sleep-disordered breathing (defined as 10 or more apneas plus hypopneas/hr of sleep) was present in 17% of 66 men aged 22-76 and in 0 of 9 women aged 28-63 years. Three percent of men under age 40 years had sleep-disordered breathing compared with 25% of men between ages 40-59 and 75% of those above age 60. Although alcoholics with sleep-disordered breathing had a higher body mass index than those without, the increased frequency over age 40 was statistically significant after controlling for the effects of body mass index. Sleep in subjects with sleep-disordered breathing was significantly more disturbed than in subjects without sleep-disordered breathing. Our findings suggest that sleep-disordered breathing in older male alcoholics is more prevalent than has been reported in most studies of normal men and that the increase in sleep-disordered breathing that occurs with age in alcoholics is greater than the age-related increase in sleep-disordered breathing that occurs in healthy elderly men. Furthermore, sleep-disordered breathing is a significant contributor to sleep disturbance in a substantial proportion of male alcoholics above the age of 40 years.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
117.
Levels of analysis issues have attracted a lot of attention in group psychology research. Despite assertions pertaining to the value of multilevel models, most researchers focus on either the individual within groups or the group as a whole, but seldom on both. A multilevel approach may be helpful to group psychologists. This article addresses levels of analysis issues that are an inherent part of group research, and a number of methods that can be used to analyze multilevel data are presented. The methods fall into 3 categories: (a) assessing the extent of agreement within a single group, (b) contrasting within-group and between-groups variance, and (c) conducting multiple-level analyses. Finally, recommendations are offered for future multilevel research. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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WG Henderson T Moritz S Goldman J Copeland G Sethi 《Canadian Metallurgical Quarterly》1995,16(5):331-341
From 1983 to 1987, the Department of Veterans Affairs (DVA) Cooperative Studies Program (CSP) conducted a multicenter clinical trial (CSP #207) to determine whether four different antiplatelet regimens compared to placebo could prevent the occlusion of grafts following coronary artery bypass surgery. The study showed that all of the active regimens tended to be better than placebo and that the three regimens containing aspirin were statistically significantly better. A cumulative meta-analysis of 12 trials performed shortly before the end of CSP #207 raised the issue as to whether the meta-analysis, if done earlier, would have changed the conduct of the trial. At the start of the planning period, one trail of size n = 37 had been published with a nonsignificant odds ratio (OR) of 0.74 (95% CI: 0.18, 3.12). At the time that CSP # 207 was approved by the DVA Cooperative Studies Evaluation Committee, two trials had been published (cumulative n = 150, OR = 0.44, 95% CI 0.19, 0.99). At the time patient intake started, five trials showed cumulative n = 769, OR = 0.42, 95% CI = 0.26, 0.68. Although the first 6-month CSP #207 progress report showed no treatment effect, by the time of the 12-month review by the Data Monitoring Board (DMB) a trend was developing in favor of active treatment. If the results of the meta-analysis had been available to the DMB at that time, conceivably the Board would have recommended stopping the placebo arm because of a convincing treatment effect based on the totality of the evidence. Cumulative meta-analysis could be useful as an adjunct in the planning, conduct, and final analysis of a clinical trial. It could also be used as one piece of evidence in the monitoring of the ongoing phase of a trial. 相似文献
120.
We reduce the solution of a Riccati equation for infinite-time linear quadratic controllers with continuous delays and n state variables to the problem of finding scalar parameter values for an integral kernel whose form is completely specified. To simplify the exposition, the reduction is described only for a special case involving 2-dimensional state variables, but the method is entirely general. An abstract formulation of Vinter and Kwong is used throughout. 相似文献