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排序方式: 共有3023条查询结果,搜索用时 15 毫秒
61.
Liane A. Arcinas Weiang Yan Davinder S. Jassal Michael P. Love Michael H. Yamashita Basem Elbarouni 《The Canadian journal of cardiology》2018,34(12):1688.e5-1688.e7
We describe a case of a 54-year-old woman who had a right cardiac mass found on coronary angiography. Echocardiography, computed tomography, and cardiac magnetic resonance imaging characterized it as a thrombosed giant right coronary artery aneurysm. This was confirmed on pathology. We present the role of multimodality cardiovascular imaging in the diagnosis and characterization of a giant coronary artery aneurysm. 相似文献
62.
A. M. Getachew G. Innocent C. J. Proudman A. Trawford G. Feseha S. W. J. Reid B. Faith S. Love 《Parasitology research》2013,112(1):141-146
The efficacy of an oral formulation of praziquantel (Equitape, Horse paste, Fort Dodge) in the reduction of cestode egg counts and serum antibody level against Anoplocephala perfoliata was assessed in 44 donkeys under field conditions. The donkeys were confirmed both by faecal examination and serum antibody assessed by an enzyme-linked immunosorbent assay to have natural infection with tapeworms. The donkeys were randomly allocated into treatment (n?=?22) and control (n?=?22) groups. The treatment group was treated with both praziquantel and ivermectin (Ivomec, Merial) at a dose rate of 1 mg/kg and 200 μg/kg, respectively while the control group was treated only with ivermectin. Faecal samples were collected before treatment (day-0) and 2, 6, 8, 12, and 16 weeks post-treatment while blood samples were collected before treatment and 8 and 16 weeks after treatment and analysed. The results of the study demonstrated that praziquantel paste was highly effective in reducing cestode eggs in donkeys and had an efficacy of more than 99 % until week 16 (day?112). No cestode egg reappearance by 16 weeks post-treatment in any animal in the treatment group was observed while donkeys in the control group continued shedding cestode eggs. The immunological assay also showed a significant reduction in serum antibody level against A. perfoliata in treated donkeys compared to the control group (p?=?0.0001). This marked decrease in serum antibody level indicates reduced risk of cestode-associated colic and other gastrointestinal disorders and clinical diseases. No adverse reactions or clinical effects were encountered in any animal within either group throughout the trial period. 相似文献
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65.
Allison J. Lazard Anthony Dudo Tessa Dennis Mary Grace Ewald Brad Love 《Health communication》2017,32(4):470-482
Understanding the influence of visual design, as the access point for online health communication, is key as Americans are increasingly sickened by an obesity epidemic. Nutritional websites that deliver critical health information should be considered as a potential strategy to fight against the grave consequences of obesity, as research indicates that consumers are consistently turning to the Internet as a resource for health information. Focusing on nutritional websites, this study analyzes the use of visual design principles that are known to greatly influence first impressions and appeal of the information from the user’s perspective. The results suggest there are opportunities for improvement to the online communication of nutritional information to increase the likelihood of users’ favorable first impressions, the critical first steps for nutritional information delivery goals. 相似文献
66.
Aims: We provide evidence that the use of perfusion imaging reveals the neuroanatomical basis for a behaviourally demonstrated cognitive deficit that is not revealed via standard neuroradiological imaging techniques. Methods & Procedures: We present a case study of a 52-year-old female stroke survivor (16 years post onset) whose speech was fluent and grammatical with some word-finding difficulties that were typically overcome with common circumlocution strategies. Based on standardised measures, the patient's clinical diagnosis was anomic aphasia. In addition to word-finding deficits, it was discovered that this patient also demonstrated difficulties in reading; while able to eventually read and understand text, there was extreme difficulty in completing such tasks. A series of experimental findings exploring this reading deficit are presented. This patient's lesion, as revealed via structural brain imaging, did not involve a brain region typically implicated in reading dysfunction. This behaviour-lesion inconsistency was explored via perfusion MRI technology as a means of assessing whether other neural regions not directly implicated in the structural scans (such as the angular gyrus) could in fact show some level of dysfunction. Outcomes & Results: Behavioural. Analysis of the patient's overall reading time demonstrated that as compared to a matched control, this patient took significantly more time in reading paragraphs both silently and aloud. In addition, the patient produced more errors (fillers, pauses, elongations) than the matched control during the reading paragraphs aloud and story-retelling conditions. There were no differences exhibited between the patient and control with respect to content accuracy produced during these conditions. Outcomes & Results: Neuroradiological. Structural images demonstrate damage to the left basal ganglia and surrounding white matter with sparing of the left insular cortex. Collection of perfusion images (pulsed arterial spin labelling) clearly demonstrates hypoperfusion in the seemingly intact brain regions of the left angular gyrus and the left supramarginal gyrus. Conclusions: This paper presents evidence from a detailed case study that the use of perfusion imaging successfully reveals the neural basis for a reading deficit in a stroke survivor that is not revealed via standard “structural” neuroradiological imaging techniques. We argue for more standardised use of perfusion imaging, in that it reveals a brain basis for “functional lesions”, which less sensitive neuroimaging measures often fail to capture. 相似文献
67.
The role of defective fibrinolysis caused by elevated activity of plasminogen activator inhibitor-1 (PAI-1) in promoting fibrin deposition in vivo has not been well established. The present study compared the efficacy of thrombin or ancrod, a venom-derived enzyme that clots fibrinogen, to induce fibrin formation in rabbits with elevated PAI-1 levels. One set of male New Zealand rabbits received intravenous endotoxin to increase endogenous PAI-1 activity followed by a 1-hour infusion of ancrod or thrombin; another set of normal rabbits received intravenous human recombinant PAI-1 (rPAI-1) during an infusion of ancrod or thrombin. Thirty minutes after the end of the infusion, renal fibrin deposition was assessed by histopathology. Animals receiving endotoxin, rPAI-1, ancrod, or thrombin alone did not develop renal thrombi. All endotoxin-treated rabbits developed fibrin deposition when infused with ancrod (n = 4) or thrombin (n = 6). Fibrin deposition occurred in 7 of 7 rabbits receiving both rPAI-1 and ancrod and in only 1 of 6 receiving rPAI-1 and thrombin (P < .01). In vitro, thrombin but not ancrod was inactivated by normal rabbit plasma and by purified antithrombin III or thrombomodulin. The data indicate that elevated levels of PAI-1 promote fibrin deposition in rabbits infused with ancrod but not with thrombin. In endotoxin-treated rabbits, fibrin deposition that occurs with thrombin infusion may be caused by decreased inhibition of procoagulant activity and not increased PAI-1 activity. 相似文献
68.
Eosinophil autofluorescence and its use in isolation and analysis of human eosinophils using flow microfluorometry 总被引:5,自引:1,他引:5
Unstained human eosinophils exhibit unusually bright autofluorescence, which allows them to be distinguished from other leukocytes using fluorescence microscopy. Eosinophil fluorescence is associated with the cytoplasmic granules of the cells. Eosinophil granule extracts, containing an as-yet-undefined eosinophil fluorescence factor, exhibited excitation maxima at 370 nm and 450 nm, with maximum emission at 520 nm. Eosinophils adhering to opsonized parasites in vitro deposit fluorescent material onto the parasite surface. Eosinophil fluorescence was of sufficient intensity to allow the preparation of viable, highly enriched (greater than or equal to 98%), eosinophil suspensions from peripheral blood of normal and eosinophilic donors using a fluorescence- activated cell sorter. Quantitative studies of eosinophil autofluorescence were performed using flow microfluorometry. Fluorescence intensity of blood eosinophils from normal volunteers and eosinophilic patients varied inversely with the log of the donor's absolute eosinophil count regardless of clinical diagnosis. 相似文献
69.
C. Beglinger MD C. Knezevic MD L. Jeker U. Grötzinger MD PD Dr. K. Gyr MD MPH & TM 《Digestive diseases and sciences》1983,28(4):350-352
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems. 相似文献
70.