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The volume of data produced by genome projects, X-ray crystallography, NMR spectroscopy, and electron and confocal microscopy present the bioinformatics community with new challenges for analyzing, understanding, and exchanging this data. At the 1998 Pacific Symposium on Biocomputing, a track entitled 'Molecules to Maps: Tools for Visualization and Interaction in Computational Biology' provided tool developers and users with the opportunity to discuss advances in tools and techniques to assist scientists in evaluating, absorbing, navigating, and correlating this sea of information, through visualization and user interaction. In this paper we present these advances and discuss some of the challenges that remain to be solved. 相似文献
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Efficacy of praziquantel (0.25 mg kg(-1)) on the cecal tapeworm (Anoplocephala perfoliata) in horses
Aspiration of inflorescence or grass heads (seed head of grasses) often presents with atypical signs and symptoms because grass heads have a tendency to rapidly migrate to the periphery of the lung. If this is not recognized, it can lead to delay in diagnosis and serious complications. Removal with rigid bronchoscopy maybe difficult, and surgery is often needed. We report a case of a seven-month-old child who had a delayed diagnosis of grass head aspiration and subsequently presented with a life threatening tension pneumothorax. This case highlights the importance of obtaining a detailed history in cases of foreign body aspiration and the need to include it in the differential diagnosis of unexplained respiratory symptoms, especially those of sudden onset in children. 相似文献
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HE Greenberg MJ England ET Hellriegel TD Bjornsson 《Canadian Metallurgical Quarterly》1997,37(6):480-485
The time of peak concentration after administration of oral drug is an often quoted and used pharmacokinetic parameter. It is not well appreciated, however, that the peak times after a single dose and a dose at steady state during a multiple administration regimen can differ significantly. This article derives the mathematical relationships that determine how a peak time at steady state differs from that after a single or first dose. These relationships are then evaluated using three different approaches: 1) graphic simulations of time courses of drug concentration for three hypothetical drugs; 2) comparisons of predicted and observed peak times using examples from the literature; and 3) comparisons of predicted and simulated peak times based on different sampling schedules for three hypothetical drugs. The key finding is that peak times after a dose at steady state can occur considerably earlier after administration than after a single dose. However, the manner by which peak times are usually determined, that is, the sampling time corresponding to the highest measured drug concentration, imposes significant limitations on the usefulness of this parameter. 相似文献
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WC Widrich AH Robbins DC Nabseth ET O''Hara WC Johnson KV Loughlin 《Canadian Metallurgical Quarterly》1976,121(2):295-302
A series of ergot alkaloids, together with the DA agonists apomorphine and piribedil, were tested for protective effects against audiogenic seizures in an inbred strain of mice (DBA/2) and for induction of circling behaviour in mice with unilateral destruction of one nigrostriatal DA pathway. The order of potency against audiogenic seizures was apomorphine greater than ergocornine greater than bromocryptine greater than ergometrine greater than LSD greater than methysergide greater than piribedil while that observed in the rotating mouse model was apomorphine greater than ergometrine greater than ergocornine greater than bromocryptine greater than piribedil. LSD caused only weak circling behaviour even when administered in high doses (greater than 1 mg/kg). Methysergide was ineffective. Prior administration of the neuroleptic agent haloperidol blocked the effect of DA agonists and of ergot alkaloids in both animal models. The possible action of ergot alkaloids as DA agonists is discussed. 相似文献
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Experimental reproduction and antibody inhibition of marble spleen disease of pheasants 总被引:1,自引:0,他引:1
An extract of spleens from three pheasants affected with marble spleen disease was used as an intravenous inoculum to transmit the disease to pen reared pheasants (Phasianus colchicus x Phasianus torquatus). The disease was prevented by specific convalescent pheasant antiserum and by antiserum from turkeys that had recovered from hemorrhagic enteritis of turkeys. The causative agent of the disease passed through 0.22 mu filters, resisted chloroform and retained its precipitin antigen quality after propagation by bird passage. Filterability, chloroform resistance, antigenic characteristics and in vivo response to antibody strongly indicate that the causative agents of marble spleen disease is a virus very similar to the virus which causes hemorrhagic enteritis of turkeys. 相似文献
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