152 resultados para iodinated contrast agents


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The data-oriented empirical research on the Chinese adverb “ke” has led to the conclusion that the semantics of the word as a modal adverb is always two-fold: it marks both “contrast” and “emphasis”. “Adversativity” as used in literature on “ke” is but one type of contrast marked by “ke”. Other types of contrast marked by “ke” in declarative sentences include: a) what is assumed by the hearer and what the truth of a matter is; b) what the sentence literally talks about and what it also implicitly conveys; and c) the original wishful nature of the stated action and its final realization. In all declarative sentences, what the adverb emphasizes is the “factuality” of what is stated. Chinese Abstract [提要] 对外汉语教学的实践表明,汉语副词“可”是教学中的难点,这跟我们对其语义内涵缺乏全面准确的认识有关。为了全面揭示副词“可”的核心语义,本作者以电视连续剧《渴望》前二十集为主要语料,并结合其他一些电视剧、电视节目以及文献里已有的语料,对出现在各种语境中的“可”进行了大量的考察和归纳性研究。研究结果表明,作为语气副词的“可”其核心语义不是单一的,它总是在标示“对比”(即“不同”)的同时表示强调。它所强调的是所述内容的“事实性”或“终然性”。由于篇幅所限,本文仅对陈述句中的语气副词“可”加以讨论

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This article examines the new Property Occupations Act 2014 (POA) and relevant provisions of the Agents Financial Administration Act 2014 (AFAA) and the impacts for property practitioners. The Acts are due to commence later in 2014 once regulations and relevant forms are drafted. Coinciding with the commencement of the Acts further versions of the REIQ Houses and Land Contract and REIQ Community Title Contract will also be released. The POA introduces changes for licencing of real estate agents, property developers and resident letting agents as well as significant changes for the contract formation process. The AFAA includes the trust account and claim fund provisions of PAMDA, which avoids duplication of these provisions across each of the industry-specific Bills. The most significant change is to the process for making a claim against the fund for the conduct of property agents.

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Recently, we inserted the plasmid vector pKK233-2 containing rat GSH S-transferase (GST) 5-5 cDNA into Salmonella typhimurium TA1535 and found that these bacteria [GST 5-5(+)] expressed the protein and produced mutations when ethylene or methylene dihalides were added [Thier, R., Taylor, J. B., Pemble, S. E., Ketterer, B., Persmark, M., Humphreys, W. G., and Guengerich, F. P. (1993) Proc. Natl. Acad. Sci. U.S.A. 90, 8576-8580]. After exposure to the known GST 5-5 substrate 1,2-epoxy-3-(4′-nitrophenoxy)propane, the GST 5-5(+) strain showed fewer mutants than the bacteria transfected with the cDNA clone in a reverse orientation [GST 5-5(-)], suggesting a protective role of GST 5-5. However, mutations were considerably enhanced in the GST 5-5(+) strain [as compared to GST 5-5(-)] when 1,2,3,4-diepoxybutane (butadiene diepoxide) or 1,2-epoxy-4-bromobutane was added. The GST 5-5(+) and GST 5-5(-) bacterial stains showed similar responses to 1,2-epoxypropane, 3,4-epoxy-1-butene, and 1,4-dibromobutane. The results suggest that some bifunctional activated butanes are transformed to mutagenic products through GSH conjugation. We also found that the GST 5-5(+) strain showed enhanced mutagenicity with 1,4-dibromo-2,3-epoxybutane, 1,2-epoxy-3-bromopropane (epibromohydrin), and (±)-1,4-dibromo-2,3-dihydroxybutane. The possibility was considered that a 5-membered thialonium ion may be involved in the mutagenicity. Model thialonium compounds were rather stable to hydrolysis in aqueous solution at pH 7.4 and slowly alkylated 4-(4-nitrobenzyl)pyridine. The presence of a hydroxyl group β to the sulfur did not enhance reactivity. Mechanisms involving episulfonium ions are considered more likely. Potential oxidation products of the toxic pesticide 1,2-dibromo-3-chloropropane (DBCP) were also considered in this system. DBCP itself gave rather similar results in the two strains. Others have reported that oxidation of DBCP is required for mutagenicity, along with GST-catalyzed GSH conjugation [Simula, T. P., Glancey, M. J., Söderlund, E. J., Dybing, E., and Wolf, C. R. (1993) Carcinogenesis 14, 2303-2307]. The putative oxidation product 1,2-dibromopropional did not show a difference between the two strains. However, 1,3-dichloroacetone, a model for the putative oxidation product 1-bromo-3-chloroacetone, was considerably more mutagenic in the GST 5-5(+) strain.

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Purpose: Older adults have increased visual impairment, including refractive blur from presbyopic multifocal spectacle corrections, and are less able to extract visual information from the environment to plan and execute appropriate stepping actions; these factors may collectively contribute to their higher risk of falls. The aim of this study was to examine the effect of refractive blur and target visibility on the stepping accuracy and visuomotor stepping strategies of older adults during a precision stepping task. Methods: Ten healthy, visually normal older adults (mean age 69.4 ± 5.2 years) walked up and down a 20 m indoor corridor stepping onto selected high and low-contrast targets while viewing under three visual conditions: best-corrected vision, +2.00 DS and +3.00 DS blur; the order of blur conditions was randomised between participants. Stepping accuracy and gaze behaviours were recorded using an eyetracker and a secondary hand-held camera. Results: Older adults made significantly more stepping errors with increasing levels of blur, particularly exhibiting under-stepping (stepping more posteriorly) onto the targets (p<0.05), while visuomotor stepping strategies did not significantly alter. Stepping errors were also significantly greater for the low compared to the high contrast targets and differences in visuomotor stepping strategies were found, including increased duration of gaze and increased interval between gaze onset and initiation of the leg swing when stepping onto the low contrast targets. Conclusions: These findings highlight that stepping accuracy is reduced for low visibility targets, and for high levels of refractive blur at levels typically present in multifocal spectacle corrections, despite significant changes in some of the visuomotor stepping strategies. These findings highlight the importance of maximising the contrast of objects in the environment, and may help explain why older adults wearing multifocal spectacle corrections exhibit an increased risk of falling.

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The human choroid is capable of rapidly changing its thickness in response to a variety of stimuli. However little is known about the role of the autonomic nervous system in the regulation of the thickness of the choroid. Therefore, we investigated the effect of topical parasympatholytic and sympathomimetic agents upon the choroidal thickness and ocular biometrics of young healthy adult subjects. Fourteen subjects (mean age 27.9 ± 4 years) participated in this randomized, single-masked, placebo-controlled study. Each subject had measurements of choroidal thickness (ChT) and ocular biometrics of their right eye taken before, and then 30 and 60 min following the administration of topical pharmacological agents. Three different drugs: 2% homatropine hydrobromide, 2.5% phenylephrine hydrochloride and a placebo (0.3% hydroxypropyl methylcellulose) were tested in all subjects; each on different days (at the same time of the day) in randomized order. Participants were masked to the pharmacological agent being used at each testing session. The instillation of 2% homatropine resulted in a small but significant increase in subfoveal ChT at 30 and 60 min after drug instillation (mean change 7 ± 3 μm and 14 ± 2 μm respectively; both p < 0.0001). The parafoveal choroid also exhibited a similar magnitude, significant increase in thickness with time after 2% homatropine (p < 0.001), with a mean change of 7 ± 0.3 μm and 13 ± 1 μm (in the region located 0.5 mm from the fovea center), 6 ± 1 μm and 12.5 ± 1 μm (1 mm from the fovea center) and 6 ± 2 μm and 12 ± 2 μm (1.5 mm from the fovea center) after 30 and 60 min respectively. Axial length decreased significantly 60 min after homatropine (p < 0.01). There were also significant changes in lens thickness (LT) and anterior chamber depth (ACD) (p < 0.05) associated with homatropine instillation. No significant changes in choroidal thickness, or ocular biometrics were found after 2.5% phenylephrine or placebo at any examination points (p > 0.05). In human subjects, significant increases in subfoveal and parafoveal choroidal thickness occurred after administration of 2% homatropine and this implies an involvement of the parasympathetic system in the control of choroidal thickness in humans.

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Using historical and contemporary resources, this paper provides a critical account of the contemporary governance of prostitution in New South Wales. A Foucauldian approach is used to analyse the ways in which prostitution has been problematized as a health issue and managed as a public health problem. The analysis differs from other critical studies of prostitution in that it examines specific techniques of power, the operations of which have not been confined to the workings of a repressive criminal justice system. It is shown that there currently co-exists two broad understandings of prostitution in New South Wales, Australia, which have informed current initiatives to manage prostitution. Prostitutes working in public spaces have been presented as sexual agents wilfully engaged in criminal conduct and the spread of contagion. They have been subject to intense official scrutiny and regulated through criminal sanctions. In contrast, prostitutes working in private spaces have been presented as victims of adverse circumstance, deserving of protection and compassion. They have been made subject to strategic interventions that have attempted to normalize prostitution and render the prostitute a hygienic subject.

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This study considered the relationship between professional learning, teacher agency and school improvement. Specifically, it explored the principal's role in supporting teacher agency in their professional learning. It found that, with appropriate pressure and support from principals, school improvement for the betterment of student learning is attainable through teacher professional learning that is based 'within' a school. Particularly, it ascertained that schools need to give greater attention to the allocation of time for teacher professional learning, specifically: time before, during and after professional learning activities. Privileging time efficiently and effectively, heightens teacher agency in their learning.

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In contrast to single robotic agent, multi-robot systems are highly dependent on reliable communication. Robots have to synchronize tasks or to share poses and sensor readings with other agents, especially for co-operative mapping task where local sensor readings are incorporated into a global map. The drawback of existing communication frameworks is that most are based on a central component which has to be constantly within reach. Additionally, they do not prevent data loss between robots if a failure occurs in the communication link. During a distributed mapping task, loss of data is critical because it will corrupt the global map. In this work, we propose a cloud-based publish/subscribe mechanism which enables reliable communication between agents during a cooperative mission using the Data Distribution Service (DDS) as a transport layer. The usability of our approach is verified by several experiments taking into account complete temporary communication loss.

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In this issue of Cancer Discovery, Hagel and colleagues report the design and the in vitro and in vivo activity of a novel, irreversible, paralog-specific kinase inhibitor of FGFR4, BLU9931. This compound binds covalently to a cysteine residue in the hinge region of FGFR4 but not in FGFR1-3. BLU9931 induces tumor shrinkage in hepatocellular carcinoma models that express a functioning ligand/receptor complex consisting of FGF19/FGFR4/KLB and adds to a growing list of anti-FGFR4 agents.

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Microtubules (MTs) play important and diverse roles in eukaryotic cells. Their function and biophysical properties have made α−and β−tubulin, the main components of MTs, the subject of intense study. Interfering with normal MT dynamics, for example, by the addition of tubulin ligands, can cause the cell great distress and affect MT stability and functions, including mitosis, cell motion and intracellular organelle transport. It has been shown in the literature that tubulin is an important target molecule for developing anticancer drugs. Tubulin binding molecules have generated considerable interest after the successful introduction of the taxanes into clinical oncology and the widespread use of the vinca alkaloids vincristine and vinblastine. These compounds inhibit cell mitosis by binding to the protein tubulin in the mitotic spindle and preventing polymerization into the MTs. This mode of action is also shared with other natural agents eg colchicine and podophyllotoxin. However various tubulin isotypes have shown resistance to taxanes and other MT agents. Therefore, there is a strong need to design and develop new natural analogs as antimitotic agents to interact with tubulin at sites different from those of vinca alkaloids and taxanes. This minireview provides SAR on several classes of antimitotic agents reported in the literature. The structures and data given are essential to the scientists who are involved in drug design and development in the field of anticancer drugs.

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Pharmacological MRI (phMRI) techniques can be used to monitor the neurophysiological effects of central nervous system (CNS) active drugs. In this study, we investigated whether dynamic susceptibility contrast (DSC) perfusion imaging employing the use of superparamagnetic iron oxide nanoparticles (Resovist) could be used to measure hemodynamic response to d-amphetamine challenge in human subjects at both 1.5 and 4 T. Significant changes in cerebral blood flow (CBF) were found in focal regions associated with the nigrostriatal circuit and mesolimbic and mesocortical dopaminergic pathways. More significant CBF responses were found at higher field strength, mainly within striatal structures. The results from this study indicate that DSC perfusion imaging using Resovist can be used to assess the efficacy of CNS-active drugs and may play a role in the development of novel psychiatric therapies at the preclinical level. © 2005 Wiley-Liss, Inc.

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The Company B production of Samuel Beckett's Waiting for Godot raises important questions about copyright law, moral rights, and dramatic works. The playwright's nephew and executor, Edward Beckett, threatened to bring a legal action against the Sydney company for breach of contract on the grounds that unauthorised music appeared in the production. The Company B production denied that the contract made any such express provisions. The director Neil Armfield complained: 'In coming here with its narrow prescriptions, its dead controlling hand, the Beckett estate seems to me to be the enemy of art'. In the biography Damned to fame, James Knowlson documents a number of other proceedings taken by Beckett and his agents to control the productions of his work: 'He was often represented as a tyrannical figure, an arch-controller of his work, ready to unleash fiery thunderbolts onto the head of any bold, innovative director, unwilling to follow his text and stage directions to the last counted dot and precisely timed pause.' However, Knowlson notes that Beckett was inconsistent in his willingness to use legal action: 'It made a tremendous difference if he liked and respected the persons involved or if he had been able to listen to their reasons for wanting to attempt something highly innovative or even slightly different'. Famously, in 1988, Beckett brought legal action against a Dutch theatre company, which wanted to stage a production of Waiting for Godot, with women acting all the roles. His lawyer argued that the integrity of the text was violated because actresses were substituted for the male actors asked for in the text. The judge in the Haarlem court ruled that the integrity of the play had not been violated, because the performance showed fidelity to the dialogue and the stage directions of the play. By contrast, in 1992, a French court held a stage director was liable for an infringement of Beckett's moral right of integrity because the director had staged Waiting for Godot with the two lead roles played by women. In 1998, a United States production of Waiting for Godot with a racially mixed cast attracted legal threats amid accusations it had 'injected race into the play'. In the 2000 New York Fringe Festival, a company made light of this ongoing conflict between the Beckett estate and artistic directors. The work was entitled: The complete lost works of Samuel Beckett as found in an envelope (partially burned) in a dustbin in Paris labelled 'Never to be performed. Never. Ever. EVER! Or I'll sue! I'LL SUE FROM THE GRAVE!'. The plot concerned a fight between three producers and the Beckett estate. In the wake of such disputes, Beckett and later his estate sought to tighten production contracts to state that no additions, omissions or alterations should be made to the text of the play or the stage directions and that no music, special effects or other supplements should be added without prior consent.

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High contrast ratios between windows and surrounding surfaces could cause reduced visibility or discomfort for occupants. Consequently, building users may choose to intervene in lighting conditions through closing blinds and turning on the lamps in order to enhance indoor visual comfort. Such interventions increase projected electric lighting use in buildings. One simple method to prevent these problematic issues is increasing the luminance of the areas surrounding to the bright surface of windows through the use of energy-efficient supplementary lighting, such Light Emitting Diodes (LEDs). This paper reports on the results of a pilot study in conventional office in Brisbane, Australia. The outcomes of this study indicated that a supplementary LED system of approximately 18 W could reduce the luminance contrast on the window wall from values in the order of 117:1 to 33:1. In addition, the results of this experiment suggested that this supplementary strategy could increase the subjective scale appraisal of window appearance by approximately 33%, as well as reducing the likelihood of users’ intention to turn on the ceiling lights by about 27%. It could also diminish the likelihood of occupants’ intention to move the blind down by more than 90%.

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Background: Transthoracic echocardiography (TTE) during extra corporeal membrane oxygenation (ECMO) is important but can be technically challenging. Contrast-specific TTE can improve imaging in suboptimal studies. These contrast microspheres are hydrodynamically labile structures. This study assessed the feasibility of contrast echocardiography (CE) during venovenous (VV) ECMO in a validated ovine model. Method: Twenty-four sheep were commenced on VV ECMO. Parasternal long-axis (Plax) and short-axis (Psax) views were obtained pre- and postcontrast while on VV ECMO. Endocardial definition scores (EDS) per segment were graded: 1 = good, 2 = suboptimal 3 = not seen. Endocardial border definition score index (EBDSI) was calculated for each view. Endocardial length (EL) in the Plax view for the left ventricle (LV) and right ventricle (RV) was measured. Results: Summation EDS data for the LV and RV for unenhanced TTE (UE) versus CE TTE imaging: EDS 1 = 289 versus 346, EDS 2 = 38 versus 10, EDS 3 = 33 versus 4, respectively. Wilcoxon matched-pairs rank-sign tests showed a significant ranking difference (improvement) pre- and postcontrast for the LV (P < 0.0001), RV (P < 0.0001) and combined ventricular data (P < 0.0001). EBDSI for CE TTE was significantly lower than UE TTE for the LV (1.05 ± 0.17 vs. 1.22 ± 0.38, P = 0.0004) and RV (1.06 ± 0.22 vs. 1.42 ± 0.47, P = 0.0.0006) respectively. Visualized EL was significantly longer in CE versus UE for both the LV (58.6 ± 11.0 mm vs. 47.4 ± 11.7 mm, P < 0.0001) and the RV (52.3 ± 8.6 mm vs. 36.0 ± 13.1 mm, P < 0.0001), respectively. Conclusions: Despite exposure to destructive hydrodynamic forces, CE is a feasible technique in an ovine ECMO model. CE results in significantly improved EDS and increased EL.