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S. P. Allison 《BMJ (Clinical research ed.)》1994,309(6967):1499-1500
Until the results of early intervention trials are known, computed tomography should be used selectively rather than routinely in all patients with stroke. Scanning may be advised in young patients (under 65 years) or in those with an atypical course where there is diagnostic doubt and computed tomography would influence management. The cost and medicolegal implications of routine scanning are enormous and should be considered carefully in relation to other and possibly more effective strategies. 相似文献
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M A Handel J Papaconstantinou D P Allison E M Julku E T Chin 《Developmental biology》1973,35(2):240-249
During the mid to late 4th instar period of larval development, the mitochondria of Rhynchosciara spermatocytes undergo highly characteristic morphological changes. In late meiosis the enlarged mitochondria fuse to form a single mitochondrial element which will ultimately extend the length of the spermatid tail. Our studies have shown that synthesis of a circular DNA occurs during this period of mitochondrial “differentiation.” This DNA has a density of 1.681 g/cm3; and its synthesis cannot be detected in somatic tissues such as salivary gland, fat body, or gastric cecum. From analysis of DNA extracted from mitochondrial pellets, we have shown that the circular DNA is associated with the mitochondria. The contour length of the mitochondrial DNA is 9 μm, equivalent to a molecular weight of 18 × 106. Although most metazoan mitochondrial DNAs exhibit contour lengths of approximately 5 μm (10 × 105 daltons), there is no extractable 5 μm circular DNA in these spermatocytes. Therefore, we conclude that either Rhynchosciara spermatocytes possess a distinct 9 μm mitochondrial DNA or that the spermatocyte mitochondrial DNA represents dimers of 5 μm monomers. 相似文献
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Olga R. Yamilova Ilya V. Martynov Allison S. Brandvold Irina V. Klimovich Alex H. Balzer Alexander V. Akkuratov Ilya E. Kusnetsov Natalie Stingelin Pavel A. Troshin 《Liver Transplantation》2020,10(7)
In view of a rapid development and increase in efficiency of organic solar cells, reaching their long‐term operational stability represents now one of the main challenges to be addressed on the way toward commercialization of this photovoltaic technology. However, intrinsic degradation pathways occurring in organic solar cells under realistic operational conditions remain poorly understood. The light‐induced dimerization of the fullerene‐based acceptor materials discovered recently is considered to be one of the main causes for burn‐in degradation of organic solar cells. In this work, it is shown that not only the fullerene derivatives but also different types of conjugated polymers and small molecules undergo similar light‐induced crosslinking regardless of their chemical composition and structure. In the case of conjugated polymers, crosslinking of macromolecules leads to a rapid increase in their molecular weight and consequent loss of solubility, which can be revealed in a straightforward way by gel permeation chromatography analysis via a reduction/loss of signal and/or smaller retention times. Results of this work, thus, shift the paradigm of research in the field toward designing a new generation of organic absorbers with enhanced intrinsic photochemical stability in order to reach practically useful operation lifetimes required for successful commercialization of organic photovoltaics. 相似文献
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Allison Lange Milo B. Fasken Murray Stewart Anita H. Corbett 《Traffic (Copenhagen, Denmark)》2020,21(10):622-635
The importin α/β transport machinery mediates the nuclear import of cargo proteins that bear a classical nuclear localization sequence (cNLS). These cargo proteins are linked to the major nuclear protein import factor, importin‐β, by the importin‐α adapter, after which cargo/carrier complexes enter the nucleus through nuclear pores. In the nucleus, cargo is released by the action of RanGTP and the nuclear pore protein Nup2, after which the importins are recycled to the cytoplasm for further transport cycles. The nuclear export of importin‐α is mediated by Cse1/CAS. Here, we exploit structures of functionally important complexes to identify residues that are critical for these interactions and provide insight into how cycles of protein import and recycling of importin‐α occur in vivo using a Saccharomyces cerevisiae model. We examine how these molecular interactions impact protein localization, cargo import, function and complex formation. We show that reversing the charge of key residues in importin‐α (Arg44) or Cse1 (Asp220) results in loss of function of the respective proteins and impairs complex formation both in vitro and in vivo. To extend these results, we show that basic residues in the Nup2 N‐terminus are required for both Nup2 interaction with importin‐α and Nup2 function. These results provide a more comprehensive mechanistic model of how Cse1, RanGTP and Nup2 function in concert to mediate cNLS‐cargo release in the nucleus. 相似文献
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Brooke Sadler Jackson Wilborn Lilian Antunes Timothy Kuensting Andrew T. Hale Stephen R. Gannon Kevin McCall Carlos Cruchaga Matthew Harms Norine Voisin Alexandre Reymond Gerarda Cappuccio Nicola Brunetti-Pierri Marco Tartaglia Marcello Niceta Chiara Leoni Giuseppe Zampino Allison Ashley-Koch Gabe Haller 《American journal of human genetics》2021,108(1):100-114