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81.
Joseph H. Bochner Wayne M. Garrison Karen A. Doherty 《International journal of audiology》2015,54(7):490-498
Objective: The purpose of this study was to collect and analyse data necessary for expansion of the NSRT item pool and to evaluate the NSRT adaptive testing software. Design: Participants were administered pure-tone and speech recognition tests including W-22 and QuickSIN, as well as a set of 323 new NSRT items and NSRT adaptive tests in quiet and background noise. Performance on the adaptive tests was compared to pure-tone thresholds and performance on other speech recognition measures. The 323 new items were subjected to Rasch scaling analysis. Study sample: Seventy adults with mild to moderately severe hearing loss participated in this study. Their mean age was 62.4 years (sd = 20.8). Results: The 323 new NSRT items fit very well with the original item bank, enabling the item pool to be more than doubled in size. Data indicate high reliability coefficients for the NSRT and moderate correlations with pure-tone thresholds (PTA and HFPTA) and other speech recognition measures (W-22, QuickSIN, and SRT). Conclusion: The adaptive NSRT is an efficient and effective measure of speech recognition, providing valid and reliable information concerning respondents’ speech perception abilities. 相似文献
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Gordon T. Taylor Frank E. Muller-Karger Robert C. Thunell Mary I. Scranton Yrene Astor Ramon Varela Luis Troccoli Ghinaglia Laura Lorenzoni Kent A. Fanning Sultan Hameed Owen Doherty 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(47):19315-19320
Over the last few decades, rising greenhouse gas emissions have promoted poleward expansion of the large-scale atmospheric Hadley circulation that dominates the Tropics, thereby affecting behavior of the Intertropical Convergence Zone (ITCZ) and North Atlantic Oscillation (NAO). Expression of these changes in tropical marine ecosystems is poorly understood because of sparse observational datasets. We link contemporary ecological changes in the southern Caribbean Sea to global climate change indices. Monthly observations from the CARIACO Ocean Time-Series between 1996 and 2010 document significant decadal scale trends, including a net sea surface temperature (SST) rise of ∼1.0 ± 0.14 °C (±SE), intensified stratification, reduced delivery of upwelled nutrients to surface waters, and diminished phytoplankton bloom intensities evident as overall declines in chlorophyll a concentrations (ΔChla = −2.8 ± 0.5%⋅y−1) and net primary production (ΔNPP = −1.5 ± 0.3%⋅y−1). Additionally, phytoplankton taxon dominance shifted from diatoms, dinoflagellates, and coccolithophorids to smaller taxa after 2004, whereas mesozooplankton biomass increased and commercial landings of planktivorous sardines collapsed. Collectively, our results reveal an ecological state change in this planktonic system. The weakening trend in Trade Winds (−1.9 ± 0.3%⋅y−1) and dependent local variables are largely explained by trends in two climatic indices, namely the northward migration of the Azores High pressure center (descending branch of Hadley cell) by 1.12 ± 0.42°N latitude and the northeasterly progression of the ITCZ Atlantic centroid (ascending branch of Hadley cell), the March position of which shifted by about 800 km between 1996 and 2009. 相似文献
86.
Marta Agudo Ping Yip Meirion Davies Elizabeth Bradbury Patrick Doherty Stephen McMahon Malcolm Maden Jonathan P.T. Corcoran 《Neurobiology of disease》2010,37(1):147-155
After spinal cord injury in the adult mammal, axons do not normally regrow and this commonly leads to paralysis. Retinoic acid (RA) can stimulate neurite outgrowth in vitro of both the embryonic central and peripheral nervous system, via activation of the retinoic acid receptor (RAR) β2. We show here that regions of the adult CNS, including the cerebellum and cerebral cortex, express RARβ2. We show that when cerebellar neurons are grown in the presence of myelin-associated glycoprotein (MAG) which inhibits neurite outgrowth, RARβ can be activated in a dose dependent manner by a RARβ agonist (CD2019) and neurite outgrowth can occur via phosphoinositide 3-kinase (PI3K) signalling. In a model of spinal cord injury CD2019 also acts through PI3K signalling to induce axonal outgrowth of descending corticospinal fibres and promote functional recovery. Our data suggest that RARβ agonists may be of therapeutic potential for human spinal cord injuries. 相似文献
87.
Jennifer S. Temel Joseph A. Greer Sonal Admane Jessica Solis Barbara J. Cashavelly Stephen Doherty Rebecca Heist William F. Pirl 《Journal of general internal medicine》2010,25(2):150-153
BACKGROUND
Advanced care planning (ACP) is considered an essential component of medical care in the United States, especially in patients with incurable diseases. However, little is known about clinical practices in outpatient oncology settings related to discussing end-of-life care and documenting code status preferences in ambulatory medical records. 相似文献88.
von Seidlein L Milligan P Pinder M Bojang K Anyalebechi C Gosling R Coleman R Ude JI Sadiq A Duraisingh M Warhurst D Alloueche A Targett G McAdam K Greenwood B Walraven G Olliaro P Doherty T 《Lancet》2000,355(9201):352-357
This double-blind, randomized, controlled study investigated the efficacy, safety and tolerability of artesunate plus pyrimethamine-sulphadoxine for uncomplicated malaria among Gambian children. Combined use of artesunate and pyrimethamine-sulphadoxine was hypothesized to delay or prevent resistance, which proved to be effective in reducing childhood mortality in sub-Saharan Africa. A total of 600 children with acute uncomplicated Plasmodium falciparum malaria, 6 months to 10 years old, were randomly administered pyrimethamine-sulphadoxine (25 mg/500 mg) with placebo, 4 mg/kg body weight pyrimethamine-sulphadoxine plus 1 dose of artesunate, or pyrimethamine-sulphadoxine plus 4 mg/kg body weight artesunate for 3 days. Results indicate that combined treatment was well tolerated. On day 1, 178 of 381 children treated with artesunate were still parasitemic compared with 157 of 195 children in the pyrimethamine-sulphadoxine group. On the other hand, failure rates on day 14 were 3.1% in the pyrimethamine-sulphadoxine group and 3.7% in the 1-dose artesunate group and 1.6% in the 3-dose group. Insignificant differences were found among children administered 1-dose and 3-dose artesunate, and were found less likely to be gametocytemic after treatment. In conclusion, this study confirms the safety and efficacy of a combined treatment, which eventually results in lower gametocyte rates and lower transmission rates. 相似文献
89.
C J Birch D P Tyssen G Tachedjian R Doherty K Hayes A Mijch C R Lucas 《The Journal of infectious diseases》1992,166(1):108-112
Three AIDS patients with severe cutaneous herpes simplex virus (HSV) infection refractory to therapy with acyclovir and foscarnet (2 patients) were treated with a topical preparation of trifluorothymidine (TFT) and interferon-alpha. Complete healing of lesions occurred in 1 patient; a second had significant regression of the infected area. In the third, the lesion was stabilized twice after application of the preparation and reduced in size after a subsequent treatment. In vitro studies confirmed that isolates from these patients were acyclovir- or acyclovir/foscarnet-resistant. In addition, they revealed strong synergy between TFT and interferon-alpha for these isolates and for strains with wild-type drug sensitivity profiles. Topical TFT/interferon-alpha may be of benefit in the therapy of mucocutaneous HSV infections, especially when they are resistant to treatment with systemic antiviral agents. 相似文献
90.
Warkentin TE; Hayward CP; Boshkov LK; Santos AV; Sheppard JA; Bode AP; Kelton JG 《Blood》1994,84(11):3691-3699
Heparin-induced thrombocytopenia is characterized by moderate thrombocytopenia and thrombotic complications, whereas quinine/quinidine-induced thrombocytopenia usually presents with severe thrombocytopenia and bleeding. Using flow cytometry and assays of procoagulant activity, we investigated whether sera from patients with these immune drug reactions could stimulate normal platelets to generate platelet-derived microparticles with procoagulant activity. Sera or purified IgG from patients with heparin-induced thrombocytopenia stimulated the formation of platelet-derived microparticles in a heparin-dependent fashion. Further studies showed that heparin-induced thrombocytopenia sera also produced a marked increase in procoagulant activity. In contrast, sera from patients with quinine- or quinidine-induced thrombocytopenia did not generate platelet-derived microparticles nor generate increased procoagulant activity. However, quinine/quinidine-induced thrombocytopenia sera produced a significant increase in the binding of IgG to platelets in a drug-dependent fashion, whereas sera from patients with heparin-induced thrombocytopenia demonstrated no drug-dependent binding of IgG to platelets. We also observed increased levels of circulating microparticles in patients with acute heparin-induced thrombocytopenia compared with control patients. Our observations indicate that the generation of procoagulant platelet-derived microparticles in vivo is a plausible explanation for the thrombotic complications observed in some patients with heparin-induced thrombocytopenia. 相似文献