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101.
For many glycosyltransferases, the information that instructs Golgi localization is located within a relatively short sequence
of amino acids in the N-termini of these proteins comprising: the cytoplasmic tail, the transmembrane spanning region, and
the stem region (CTS). Also, one enzyme may be more reliant on a particular region in the CTS for its localization than another.
The predominance of these integral membrane proteins in the Golgi has seen these enzymes become central players in the development
of membrane trafficking models of transport within this organelle. It is now understood that the means by which the characteristic
distributions of glycosyltransferases arise within the subcompartments of the Golgi is inextricably linked to the mechanisms
that cells employ to direct the flow of proteins and lipids within this organelle. 相似文献
102.
103.
104.
David H. Trevena 《Annals of science》2013,70(1):45-54
The famous French chemist, Marcelin Berthelot, published his first scientific paper in 1850. However, reference to this paper has been largely ignored in the various accounts of his lasting contributions to chemistry. The probable reason for this is that this paper is concerned with a method of subjecting a liquid to tension, and it is more appropriate to regard it as a paper on physics rather than on chemistry. In the work described in this largely-forgotten paper, written whilst he was still a young research student, Berthelot showed that liquids contained in his ‘Berthelot tube’ could withstand a considerable tension; and he is the first person to have observed cavitation, a phenomenon which has been studied so widely this century. The next mention in the literature of the Berthelot tube method is at the turn of the present century, after which it again seems to have been forgotten until the 1940s; since then there has been considerable progress using the Berthelot tube technique. In this paper the work described in Berthelot's original paper is discussed in some detail, and the subsequent fruitful development of the method is also traced and assessed. 相似文献
105.
106.
Robert W. Buckheit III Maria Salgado Karen O. Martins Joel N. Blankson 《Cellular and molecular life sciences : CMLS》2013,70(6):1009-1019
The mechanisms by which a small percentage of HIV-1 infected individuals known as elite suppressors or controllers are able to control viral replication are not fully understood. Early cases of viremic control were attributed to infection with defective virus, but subsequent work has demonstrated that infection with a defective virus is not the exclusive cause of control. Replication-competent virus has been isolated from patients who control viral replication, and studies have demonstrated that evolution occurs in plasma virus but not in virus isolates from the latent reservoir. Additionally, transmission pair studies have demonstrated that patients infected with similar viruses can have dramatically different outcomes of infection. An increased understanding of the viral factors associated with control is important to understand the interplay between viral replication and host control, and has implications for the design of an effective therapeutic vaccine that can lead to a functional cure of HIV-1 infection. 相似文献
107.
Eugene Kouassi Joel Sango J.M. Bosson Brou Francis N. Teubissi Kern O. Kymn 《Journal of forecasting》2012,31(7):617-638
In this paper we extend the works of Baillie and Baltagi (1999, in Analysis of Panels and Limited Dependent Variables Models, Hsiao C et al. (eds). Cambridge University Press: Cambridge, UK; 255–267) and generalize certain results from the Baltagi and Li (1992, Journal of Forecasting 11 : 561–567) paper accounting for AR(1) errors in the disturbance term. In particular, we derive six predictors for the one‐way error components model, as well as their associated asymptotic mean squared error of multi‐step prediction in the presence of AR(1) errors in the disturbance term. In addition, we also provide both theoretical and simulation evidence as to the relative efficiency of our alternative predictors. The adequacy of the prediction AMSE formula is also investigated by the use of Monte Carlo methods and indicates that the ordinary optimal predictor performs well for various accuracy criteria. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
108.
This paper provides an account of the ‘use-value’ of case-based research by showing how social scientists exploit cases, and case studies, in a variety of practices of inference and extension. The critical basis for making such extensions relies on the power of a case, or the account given of a case (the case-study account), to exemplify certain features of the social world in ways which prove valuable for further analysis: either of the same case, or in many domains beyond the original case study. Framing use-values in terms of exemplification compares favourably with understanding reasoning beyond the case either as a form of analogical reasoning or in taking cases as experimentable objects. 相似文献
109.
Octopamine content of the head of the locust Locusta migratoria has been determined during the last larval stage, moulting and adult life of 3 groups of insects: female and male gregarious, solitary and CO2 solitarized. An important difference was found between these 3 groups. Octopamine contents increased in the middle of the larval life and during the adult life. The moulting time is characterized by a sharp decrease of the octopamine content which becomes identical in the 3 groups of insects. The relation between octopamine content, hormone cycles and motility is discussed. 相似文献
110.
J C David 《Experientia》1979,35(11):1483-1484
Phenylethanolamine, m-octopamine and p-octopamine contents were determined as a function of age in the hypothalamus and brain stem of spontaneously hypertensive rats and controls Wistar Kyoto. In hypothalamus, the content of the 3 amines was 2--4-fold greater for the SH rats. In the brain stem, the phenylethanolamine and p-octopamine contents were 2--3-fold greater in SH rats but 5--6-fold higher in the case of m-octopamine. The difference appears at 3 weeks and correlates the blood pressure with the increase of age. The significance of these findings is discussed. 相似文献