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471.
Samuel J.M.M. Alberti 《Journal of the history of biology》2001,34(1):115-147
My goals in this paper are twofold: to outline there fashioning of amateur and professional roles in life science in late
Victorian Yorkshire, and to provide a revised historiography of the relationship between amateurs and professionals in this
era. Some historical treatments of this relationship assume that amateurs were demoralized by the advances of laboratory science,
and so ceased to contribute and were left behind by the autonomous “new biology.” Despite this view, I show that many amateurs
played a vital part in the construction of a professional academic community in urban Yorkshire, and then continued to collaborate
with the laboratory-based biologists. The key to any analysis of the relationship between amateurs and professionals is the
great variety of amateur identities and practices in Victorian Yorkshire. The amateur-professional riftfallacy arose because laboratory biologists fashioned an identity in conscious opposition to a particular type of amateur:
an ideal that belied an array of co-operative relationships. As naturalists refashioned their roles and identities in light
of the changes within academe and without, debates about the practice and place of life science took place as often among
amateurs as between professionals and amateurs.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
472.
N. Li J. Tuomilehto G. Dowse K. G. Alberti P. Zimmet Z. Min P. Chitson H. Gareeboo Y. Chonghua D. Fareed 《BMJ (Clinical research ed.)》1992,304(6842):1596-1601
OBJECTIVE--To compare the prevalence of electrocardiographic abnormalities and to evaluate the association between these abnormalities and the levels of coronary heart disease among Chinese living in different environments. DESIGN--Cross sectional surveys. SETTING--Beijing, China, and the island of Mauritius. SUBJECTS--Random samples of people aged 35-64 years in Beijing (621 men, 642 women) in 1984 and in Mauritius among Chinese (137 men, 130 women) and non-Chinese (1265 men, 1432 women) in 1987. MAIN OUTCOME MEASURES--Prevalence of electrocardiographic abnormalities suggesting coronary heart disease and of associated risk factors. RESULTS--Prevalence of electrocardiographic abnormalities suggesting coronary heart disease was significantly lower in Beijing (4.0%) than in Mauritian Chinese (24.3%) and Mauritian non-Chinese (24.5%). Mean serum concentrations of total and non-high density lipoprotein cholesterol were lower in Beijing Chinese than in Mauritian Chinese, but smoking and hypertension were slightly more prevalent. Overall, men with electrocardiographic abnormalities had higher risk factor levels than those with a normal electrocardiogram regardless of ethnic origin. CONCLUSIONS--The prevalence of coronary heart disease and associated risk factors was different among Chinese living in two different environments: in Beijing in the People''s Republic of China and in Mauritius. Chinese, who traditionally have a very low frequency of coronary heart disease, are by no means protected against coronary heart disease and other non-communicable diseases. Therefore, primary prevention of coronary heart disease is a major challenge for preventive medicine in China, as well as in many other developing countries. 相似文献
473.
Zoe H. Davis Laura Mediani Francesco Antoniani Jonathan Vinet Shuangxi Li Simon Alberti Bingwei Lu Alex S. Holehouse Serena Carra Onn Brandman 《Cell stress & chaperones》2021,26(3):549
Stalled mRNA translation results in the production of incompletely synthesized proteins that are targeted for degradation by ribosome-associated quality control (RQC). Here we investigated the fate of defective proteins translated from stall-inducing, nonstop mRNA that escape ubiquitylation by the RQC protein LTN1. We found that nonstop protein products accumulated in nucleoli and this localization was driven by polylysine tracts produced by translation of the poly(A) tails of nonstop mRNA. Nucleolar sequestration increased the solubility of invading proteins but disrupted nucleoli, altering their dynamics, morphology, and resistance to stress in cell culture and intact flies. Our work elucidates how stalled translation may affect distal cellular processes and may inform studies on the pathology of diseases caused by failures in RQC and characterized by nucleolar stress.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12192-021-01200-w. 相似文献
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478.
Gerd Alberti Michael Heethoff Roy A. Norton Sebastian Schmelzle Anna Seniczak Stanisław Seniczak 《Journal of morphology》2011,272(9):1025-1079
Oribatida are one of the main groups of Acari comprising mostly important decomposers in soils. Most species are particle feeders, an exceptional mode of nutrition in Arachnida. Hence, their feeding organs, the gnathosoma, are of special functional interest. We studied nearly all components using scanning and transmission electron microscopies as well as reconstructions based on synchrotron X‐ray microtomography from the model oribatid Archegozetes longisetosus. Besides cuticular structures, we describe the full set of muscles and confirm the presence of a trochanter remnant at the base of the chelicera. Setae on the prodorsum and the anterior and posterior infracapitular setae are mechanoreceptors innervated by two dendrites ending with tubular bodies. Dendrites of adoral setae, anterior setae of the chelicerae, and the supracoxal setae show neither obvious tubular bodies nor wall or terminal pores. Thus their function remains obscure. For the first time, a muscular proprioreceptor has been found in Arachnida. It likely monitors the actions of muscles moving the movable digit of the chelicera. Glandular structures within and associated with the gnathosoma are described. Dermal glands represented by secretory porose areas are found within the infracapitulum. More complex associated glands comprise the podocephalic glands and the infracapitular glands, the ducts of which were traced completely for the first time. The components described are mostly fundamental for the gnathosoma of Actinotrichida (Acariformes), one of the two lineages of Acari, to which Oribatida belong. The gnathosoma is generally considered the most relevant putative synapomorphy of Acari. Since the monophyly of Acari has become more and more questionable during the last decades, a thorough reinvestigation of this body part is necessary for a comprehensive understanding of acarine and even arachnid phylogeny and evolution. This article provides a starting point of such a re‐evaluation of the gnathosoma. J. Morphol. 2011. © 2011 Wiley‐Liss, Inc. 相似文献
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