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1.
Henryk Brzeskwiniewicz 《Biometrical journal. Biometrische Zeitschrift》1995,37(2):191-198
We present the idea of using multiresponse incomplete block designs when not all responses can be observed in all experimental units. For a special class of such designs, in which partial designs are PBB designs, a method for estimating natural treatment contrast is given. We also consider the problem of testing the hypotheses concerning the natural and any estimable treatment contrasts. For testing this hypothesis the Wald statistics, being asymptotically chi-square distributed, is proposed. 相似文献
2.
Mary T. Doan Michael D. Neinast Erika L. Varner Kenneth C. Bedi David Bartee Helen Jiang Sophie Trefely Peining Xu Jay P. Singh Cholsoon Jang J. Eduardo Rame Donita C. Brady Jordan L. Meier Kenneth B. Marguiles Zoltan Arany Nathaniel W. Snyder 《Journal of lipid research》2022,63(6):100224
Anabolic metabolism of carbon in mammals is mediated via the one- and two-carbon carriers S-adenosyl methionine and acetyl-coenzyme A. In contrast, anabolic metabolism of three-carbon units via propionate has not been shown to extensively occur. Mammals are primarily thought to oxidize the three-carbon short chain fatty acid propionate by shunting propionyl-CoA to succinyl-CoA for entry into the TCA cycle. Here, we found that this may not be absolute as, in mammals, one nonoxidative fate of propionyl-CoA is to condense to two three-carbon units into a six-carbon trans-2-methyl-2-pentenoyl-CoA (2M2PE-CoA). We confirmed this reaction pathway using purified protein extracts provided limited substrates and verified the product via LC-MS using a synthetic standard. In whole-body in vivo stable isotope tracing following infusion of 13C-labeled valine at steady state, 2M2PE-CoA was found to form via propionyl-CoA in multiple murine tissues, including heart, kidney, and to a lesser degree, in brown adipose tissue, liver, and tibialis anterior muscle. Using ex vivo isotope tracing, we found that 2M2PE-CoA also formed in human myocardial tissue incubated with propionate to a limited extent. While the complete enzymology of this pathway remains to be elucidated, these results confirm the in vivo existence of at least one anabolic three- to six-carbon reaction conserved in humans and mice that utilizes propionate. 相似文献
3.
Andreas Barth 《BBA》2007,1767(9):1073-1101
This review discusses the application of infrared spectroscopy to the study of proteins. The focus is on the mid-infrared spectral region and the study of protein reactions by reaction-induced infrared difference spectroscopy. 相似文献
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C P Ogbourne 《International journal for parasitology》1975,5(4):423-426
Observations are reported on the size and age structure of Stronglyus vulgaris populations recovered from the anterior mesenteric artery and its main branches of horses slaughtered at regular intervals throughout a year. Marked seasonal variations were found in the mean monthly numbers of worms present. During spring/early summer the numbers were relatively low and a large proportion of the arteries had no worms in them at all. Thereafter, the arterial worm burdens quite rapidly increased and the highest levels were reached during the winter months. During summer, small, newly-arrived larvae were quite abundant but by the end of the year well-developed (fifth-stage and late fourth-stage) worms predominated. These observations support the view that S. vulgaris is in Britain an annual species completing its development mainly during the winter months of the year. 相似文献
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A number of methods of construction of partially balanced incomplete block designs with nested rows and columns are developed and new balanced incomplete block designs with nested rows and columns are obtained as a by-product. 相似文献
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The Anderson-Kannemann test is a rank test for treatment effects in a randomized block design with K treatments and N blocks. In this paper, an algorithm for computing the exact distribution of the Anderson-Kannemann test statistic under the null hypothesis is deduced. Then, the exact distribution is compared with the asymptotic χ2-distribution, and it is shown that the exact distribution is approximated fairly well by the asymptotic distribution. Tables of the exact distribution are given for K = 3, N = 3(1)15; K = 4, N = 3(1)11; K = 5, N = 3(1)7; and K = 6, N = 3(1)5. 相似文献