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排序方式: 共有369条查询结果,搜索用时 15 毫秒
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Caloric stimulation induced a transient reversal of multimodal hemispatial cognitive deficits in an 81-year-old woman with an acute left cerebral hemisphere stroke. The patient had unawareness of her right hand (asomatognosia), right-sided visual unawareness (hemineglect), aphasia and right-sided weakness (hemiplegia) prior to the stimulation. Transient improvements in impaired sensory, motor, linguistic and cognitive function developed within 30 s following application of the caloric stimulus and onset of horizontal nystagmus. The effect persisted for 3 min and ceased completely after 5 min. While several recent reports have described the capacity of caloric stimulation to transiently improve or reverse a wide range of attentional, cognitive and motor impairments, most examples are in right-hemisphere-damaged patients with long-standing brain injury. Typically, patients have been tested several months or years after the onset of the deficit. A possible mechanism for the temporary reintegration of multiple cognitive functions in this patient is discussed. 相似文献
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A Particle‐Controlled,High‐Performance,Gum‐Like Electrolyte for Safe and Flexible Energy Storage Devices 下载免费PDF全文
Storing energy within flexible and safe materials is one of the most important goals for energy storage devices. To that end, high‐performance conformable electrolytes, which can transport ions quickly and safely, and can also effectively separate and bond strongly to the two electrodes, are of great importance. However, it is challenging to develop an electrolyte that can play these multiple roles simultaneously. Here, aiming to overcome this challenge, a particle‐based approach to the fabrication of a high‐performance, gum‐like electrolyte is described. The intriguing properties of the gum‐like electrolyte include high ionic conductivity, good mechanical properties, excellent adhesion properties, and, more importantly, thermal‐protection capability. It is shown that these significant properties are well‐controlled by the incorporation of wax particles with variable size, loading, and surface properties that can be designed through the use of an apporpriate surfactant. This provides a promising solution for high‐performance electrolytes and indicates a cost‐effective approach to fabricating multifunctional ion‐conducting materials. 相似文献
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Josef S. Smolen Ronald van Vollenhoven Arthur Kavanaugh Vibeke Strand Jiri Vencovsky Michael Schiff Robert Landewé Boulos Haraoui Catherine Arendt Irina Mountian David Carter Désirée van der Heijde 《Arthritis research & therapy》2015,17(1)
IntroductionAs patients with rheumatoid arthritis (RA) receive treatment with anti-tumour necrosis factors over several years, it is important to evaluate their long-term safety and efficacy. The objective of this study was to examine the safety and benefits of certolizumab pegol (CZP)+methotrexate (MTX) treatment for almost 5 years in patients with RA.MethodsPatients who completed the 24-week Rheumatoid Arthritis Prevention of Structural Damage (RAPID) 2 randomized controlled trial (RCT; ), or who were American College of Rheumatology (ACR) 20 non-responders at Week 16, entered the open-label extension (OLE; NCT00160602). After ≥6 months treatment with CZP 400 mg every two weeks (Q2W), dose was reduced to 200 mg Q2W, the approved maintenance dose. Safety data are presented from all patients who received ≥1 dose CZP (Safety population, n=612). Efficacy data are presented to Week 232 for the intent-to-treat (ITT, n=492) and Week 24 CZP RCT Completer (n=342) populations, and through 192 weeks of dose-reduction for the Dose-reduction population (patients whose CZP dose was reduced to 200 mg, n=369). Radiographic progression (modified total Sharp score change from RCT baseline >0.5) to Week 128 is reported for the Week 24 CZP Completers.ResultsIn the RCT, 619 patients were randomized to CZP+MTX (n=492) or placebo+MTX (n=127). Overall, 567 patients (91.6%) entered the OLE: 447 CZP and 120 placebo patients. Of all randomized patients, 358 (57.8%) were ongoing at Week 232. Annual drop-out rates during the first four years ranged from 8.4–15.0%. Event rates per 100 patient-years were 163.0 for adverse events (AEs) and 15.7 for serious AEs. Nineteen patients (3.1%) had fatal AEs (incidence rate=0.8). Clinical improvements in the RCT were maintained to Week 232 in the CZP Completers: mean Disease Activity Score 28 (Erythrocyte Sedimentation Rate) change from baseline was −3.4 and ACR20/50/70 responses 68.4%/47.1%/25.1% (non-responder imputation). Similar improvements observed in the ITT were maintained following dose-reduction. 73.2% of CZP Completers had no radiographic progression at Week 128.ConclusionsIn patients with active RA despite MTX therapy, CZP was well tolerated, with no new safety signals identified. CZP provided sustained improvements in clinical outcomes for almost 5 years. NCT00160641
Trial registration
ClinicalTrials.gov, and NCT00160602. Registered 8 September 2005. NCT00160641Electronic supplementary material
The online version of this article (doi:10.1186/s13075-015-0767-2) contains supplementary material, which is available to authorized users. 相似文献29.
Heraty J Ronquist F Carpenter JM Hawks D Schulmeister S Dowling AP Murray D Munro J Wheeler WC Schiff N Sharkey M 《Molecular phylogenetics and evolution》2011,60(1):73-88
The Hymenoptera--ants, bees and wasps--represent one of the most successful but least understood insect radiations. We present the first comprehensive molecular study spanning the entire order Hymenoptera. It is based on approximately 7 kb of DNA sequence from 4 gene regions (18S, 28S, COI and EF-1α) for 116 species representing all superfamilies and 23 outgroup taxa from eight orders of Holometabola. Results are drawn from both parsimony and statistical (Bayesian and likelihood) analyses, and from both by-eye and secondary-structure alignments. Our analyses provide the first firm molecular evidence for monophyly of the Vespina (Orussoidea+Apocrita). Within Vespina, our results indicate a sister-group relationship between Ichneumonoidea and Proctotrupomorpha, while the stinging wasps (Aculeata) are monophyletic and nested inside Evaniomorpha. In Proctotrupomorpha, our results provide evidence for a novel core clade of proctotrupoids, and support for the recently proposed Diaprioidea. An unexpected result is the support for monophyly of a clade of wood-boring sawflies (Xiphydrioidea+Siricoidea). As in previous molecular studies, Orussidae remain difficult to place and are either sister group to a monophyletic Apocrita, or the sister group of Stephanidae within Apocrita. Both results support a single origin of parasitism, but the latter would propose a controversial reversal in the evolution of the wasp-waist. Generally our results support earlier hypotheses, primarily based on morphology, for a basal grade of phytophagous families giving rise to a single clade of parasitic Hymenoptera, the Vespina, from which predatory, pollen-feeding, gall-forming and eusocial forms evolved. 相似文献
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Review: Production, characterization, and testing of banked mammalian cell substrates used to produce biological products 总被引:2,自引:0,他引:2
Schiff LJ 《In vitro cellular & developmental biology. Animal》2005,41(3-4):65-70
Summary A critical component in controlling the production of biological products derived from human and animal cell lines in the
characterization and testing of banked cell substrates. The objective is to confirm the identity, purity, and suitability
of these cells for manufacturing use. Quality concerns for biological products derived from cell lines originate from the
presence of cellular and adventitious contaminants. Well-characterized cell banks not only permit a consistent source of production
cells throughout the life of a product but also decrease the likelihood of contamination by other cell lines and adventitious
agents. An important part of qualifying a cell line is choosing the appropriate testing for the presence of adventitious contaminants.
The qualification of cell banks includes tests for cell identity and endogenous and adventitious microbial contaminants (bacteria,
fungi, mycoplasmas, and viruses). For cells producing recombinant deoxyribonucleic acid-derived products, analysis of the
expression construct at the nucleic acid level (genetic stability) is also a primary concern. The strategy for designing a
safety-testing program for banked cells should be based on sound scientific principles and current regulatory guidance. 相似文献