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991.
Rabbit antisera directed against a mixture of proteins solubilized from the wild-type adult Caenorhabditis elegans cuticle were used to isolate mutants, induced by ethyl methanesulfonate treatment, that exhibit alterations in surface antigenicity by immunofluorescence. Genetic mapping and complementation data for four such mutations define two genes, srf-2(I) and srf-3(IV). The mutant phenotypes observed by immunofluorescence appear to result from unmasking of antigenic determinants that are normally hidden in the wild-type cuticle. In support of this hypothesis, surface radioiodination experiments indicate that components labeled on the wild-type surface are missing or less readily labeled on the surface of srf-2 and srf-3 mutants.  相似文献   
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Background

The role of meniscus scaffolds remains controversial as failure rates remain high. The aim of this study was to evaluate the pullout strength of different suture materials used for fixation of the Collagen Meniscus Implant (CMI) regarding different suture materials, and type or temperature of irrigation fluid.

Methods

One-hundred and twelve specimens were utilized with horizontal sutures and mounted to a dedicated test device. Loads were applied perpendicular to the CMI, until failure. Two differing suture materials – polydioxanone (PDS) and non-absorbable, braided polyester sutures (NABP) – were evaluated. Additionally, two common irrigation fluids – lactated Ringer's and electrolyte-free, hypotonic Mannitol–Sorbitol solution – were evaluated. Specimens were further evaluated according to different temperatures of the irrigation fluid. Half of the constructs were tested at room temperature (20 °C) and half were evaluated at near-core body temperature (37 °C).

Results

PDS sutures showed a significantly higher load-to-failure compared to NABP sutures (P = 0.0008). Regarding the type of irrigation fluid, the electrolyte-free Mannitol–Sorbitol solution showed a significantly higher load-to-failure compared to the overall Ringer group (P b 0.0001). This was equivalent for both the PDS (P = 0.015) and for the NABP sutures (P b 0.0001). The temperature of the irrigation fluid did not significantly influence load-to-failure.

Conclusions

PDS sutures and electrolyte-free Mannitol–Sorbitol irrigation fluid provided the best biomechanical properties regarding load-to-failure testing. This study underlines the potential to improve construct stability for the CMI by alteration of the suture material and the type of irrigation fluid, which should be considered whenever scaffold fixation is conducted.  相似文献   
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The present fMRI study used a spelling task to investigate the hypothesis that the left ventral occipitotemporal cortex (vOT) hosts neuronal representations of whole written words. Such an orthographic word lexicon is posited by cognitive dual‐route theories of reading and spelling. In the scanner, participants performed a spelling task in which they had to indicate if a visually presented letter is present in the written form of an auditorily presented word. The main experimental manipulation distinguished between an orthographic word spelling condition in which correct spelling decisions had to be based on orthographic whole‐word representations, a word spelling condition in which reliance on orthographic whole‐word representations was optional and a phonological pseudoword spelling condition in which no reliance on such representations was possible. To evaluate spelling‐specific activations the spelling conditions were contrasted with control conditions that also presented auditory words and pseudowords, but participants had to indicate if a visually presented letter corresponded to the gender of the speaker. We identified a left vOT cluster activated for the critical orthographic word spelling condition relative to both the control condition and the phonological pseudoword spelling condition. Our results suggest that activation of left vOT during spelling can be attributed to the retrieval of orthographic whole‐word representations and, thus, support the position that the left vOT potentially represents the neuronal equivalent of the cognitive orthographic word lexicon. Hum Brain Mapp, 36:1393–1406, 2015. © 2014 The Authors Human Brain Mapping Published by Wiley Periodicals, Inc.  相似文献   
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