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991.
Jie Li MD Mitchell M. Goodsitt PhD Frederic Padilla PhD J. Brian Fowlkes PhD Fong Ming Hooi MS Christine R. Lashbrook RT Kai E. Thomenius PhD Paul L. Carson PhD 《Journal of ultrasound in medicine》2010,29(7):1075-1081
Objective. The goal of this work was to evaluate a possible improvement in ultrasound coverage for a dual‐modality breast imaging system in the mammographic geometry. Methods. A pilot study was performed to evaluate use of a rubber dam to retain ultrasound gel and improve imaging coverage at the breast periphery on a combined imaging system consisting of an ultrasound scanner and a digital x‐ray tomosynthesis unit. Several dams were constructed to encompass the shapes of various sizes of compressed breasts. Visual tracings of the breast‐to‐paddle contact area and breast periphery were made for 8 breasts to estimate coverage area. Two readers independently reviewed the resulting images and were asked to rate the overall breast image quality. Results. The percentages of breast in contact with the paddle were greater (P < .01) and the linear dimensions of breast in contact with the paddle were larger (P < .05) with the rubber dam than without it. With the dam, the mean estimated area of the breast in contact with the paddle increased 14%, whereas the mean increase in the fraction of the total breast area in contact with paddle was 30%. The difference was due to the mean total projected area of the breast decreasing 12% as the dam was pressed against it. The image quality of automated ultrasound with the rubber dam was consistently judged to be superior to that without the dam. Conclusions. This method can enhance the absolute and percentage area of the breast in contact with the paddle, reducing noncontact gaps at the breast periphery. Gently pressing the breast periphery with the dam inserted toward the chest wall improves coverage in automated breast ultrasound scanning. 相似文献
992.
993.
Beswick Emily Forbes Deborah Hassan Zack Wong Charis Newton Judith Carson Alan Abrahams Sharon Chandran Siddharthan Pal Suvankar 《Journal of neurology》2022,269(1):411-426
Journal of Neurology - Amyotrophic lateral sclerosis (ALS) is increasingly recognised as a multi-system disorder, presenting with common and impactful non-motor symptoms, such as... 相似文献
994.
The salubrious effects of participation in and exposure to the arts are well documented. This paper describes the development of a unique arts centre established in a disadvantaged urban school setting as part of a larger community-based health promotion research project. The discussion highlights how community-based arts programming may impact health not only through positive effects on "upstream" non-medical health determinants, particularly aspects of social support, but also through its ability to facilitate the more traditional health-promotion initiatives of the larger parent project. Also discussed is this centre's potential to act as a catalyst to achieve the overarching project goal of enhanced community health by building constitutive capacity around positive aspects of the community, rather than focusing on capacity only as an instrumental resource to solve social or health problems. Greater incorporation of the arts within health-promotion projects offers potential to enhance both health promotion practice and outcomes. 相似文献
995.
Mishra V Baines M Perry SE McLaughlin PJ Carson J Wenstone R Shenkin A 《Clinical nutrition (Edinburgh, Scotland)》2007,26(1):41-50
BACKGROUND & AIMS: This study aimed to assess the effect of high dose selenium (Se) supplementation on Se status in blood, oxidative stress, thyroid function and possible effects on requirement for renal replacement therapy (RRT) in severely septic patients admitted to the intensive care unit (ICU). METHODS: This prospective single-centre study was carried out in 40 septic ICU patients who were randomized to high dose Se (Se+ group, N=18 (474, 316, 158 microg/day), each for 3 consecutive days followed by a standard dose of 31.6 microg/day of Se given as sodium selenite whereas the control group (Se-, N=22) received only the standard dose of Se. Plasma Se, glutathione peroxidase (GSH-Px), F2 isoprostanes, thyroid function tests (total T4 and total T3), C-reactive protein (CRP) and red blood cell (RBC) GSH-Px were estimated on day 0, 3, 7, 14. RESULTS: In the Se+ group, plasma Se increased by day 3 and 7 (P<0.0001) and day 14 (P=0.02), plasma GSH-Px increased by day 3 and 7 (P=0.01) as compared to Se- group. There was a significant negative correlation between plasma Se and SOFA (sepsis related organ failure assessment) (r=-0.36, P=0.03) along with low plasma Se and high CRP at the time of admission. Requirement for renal replacement therapy was not significantly different between the groups. CONCLUSION: Although high dose Se supplementation increased plasma Se and GSH-Px activity, it did not reduce oxidative damage or the requirement for RRT. Se levels in blood are influenced by redistribution and severity of illness and therefore should be interpreted with caution. 相似文献
996.
Carson SM 《Journal of pediatric nursing》2004,19(1):74-80
The number of children receiving central venous catheters (CVCs) for the administration of medications is at an all-time high. Unfortunately, placement of these CVCs is not without risks. Infection of CVC insertion sites is one of the most common, yet often preventable, causes of nosocomial bacteremia in both children and adults worldwide. Throughout the years, multiple practice recommendations have been made regarding the proper site care of CVCs. The most popular antimicrobial solution used for site care has traditionally been povidone-iodine. Chlorhexidine gluconate solution, however, has been shown to be more effective than povidone-iodine in preventing CVC-related infections in adults. There continues to be controversy regarding the efficacy and safety of antimicrobial solutions for pediatric CVC site care. An evidence-based approach was used to determine current recommendations for CVC site care in children. 相似文献
997.
Inhibition of experimental asthma by indoleamine 2,3-dioxygenase 总被引:17,自引:0,他引:17
Hayashi T Beck L Rossetto C Gong X Takikawa O Takabayashi K Broide DH Carson DA Raz E 《The Journal of clinical investigation》2004,114(2):270-279
Epidemiological evidence points to the inverse relationship between microbial exposure and the prevalence of allergic asthma and autoimmune diseases in Westernized countries. The molecular basis for this observation has not yet been completely delineated. Here we report that the administration of certain toll-like receptor (TLR) ligands, via the activation of innate immunity, induces high levels of indoleamine 2,3-dioxygenase (IDO), the rate-limiting enzyme of tryptophan catabolism in various organs. TLR9 ligand-induced pulmonary IDO activity inhibits Th2-driven experimental asthma. IDO activity expressed by resident lung cells rather than by pulmonary DCs suppressed lung inflammation and airway hyperreactivity. Our results provide a mechanistic insight into the various formulations of the hygiene hypothesis and underscore the notion that activation of innate immunity can inhibit adaptive Th cell responses. 相似文献
998.
31P nuclear magnetic resonance studies of high energy phosphates and pH in human muscle fatigue. Comparison of aerobic and anaerobic exercise. 总被引:5,自引:3,他引:5
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R G Miller M D Boska R S Moussavi P J Carson M W Weiner 《The Journal of clinical investigation》1988,81(4):1190-1196
The goal of these experiments was to investigate the relationship of ATP, phosphocreatine (PCr), inorganic phosphate (Pi), monobasic phosphate (H2PO4-), and pH to human muscle fatigue. Phosphates and pH were measured in adductor pollicis using 31P nuclear magnetic resonance at 2.0 Tesla. The force of muscle contraction was simultaneously measured with a force transducer. The effects of aerobic and anaerobic exercise were compared using two exercise protocols: 4 min sustained maximal voluntary contraction (MVC) and 40 min of repeated intermittent contractions (75% MVC). The sustained maximal contraction produced a rapid decline of MVC and PCr, and was accompanied by a rapid rise of Pi, H+, and H2PO4-. Intermittent exercise produced steady state changes of MVC, pH, and phosphates. No significant changes of ATP were found in either protocol. During fatiguing exercise, PCr and Pi had a nonlinear relationship with MVC. H+ showed a more linear correlation, while H2PO4- showed the best correlation with MVC. Furthermore, the correlations between MVC and H2PO4- were similar in sustained (r = 0.70) and intermittent (r = 0.73) exercise. The highly significant linear relationship between increases of H+ and H2PO4- and the decline of MVC strongly suggests that both H+ and H2PO4- are important determinants of human muscle fatigue. 相似文献
999.
1000.
JEAN-JACQUES GOY FRANÇOISE TAUXE MARTIN FROMER JÜRG SCHLÄPFER PIERRE VOGT LUKAS KAPPENBERGER 《Pacing and clinical electrophysiology : PACE》1990,13(9):1142-1147
The follow-up and characteristics of 20 patients with ventricular tachycardia (VT) and no detectable heart disease is reported. These were 16 men and four women with a mean age of 44 years. Symptoms were present in 18 patients (eight had syncope and ten palpitations or dizziness), VT was sustained in 11 patients and a left bundle branch block morphology with inferior axis was found in 17 patients. In three patients, VT had a right bundle branch block morphology and left-axis deviation. The VT was inducible in 13 patients during the electrophysiological testing (EP) and was sustained in five patients. Medical treatment was introduced in 19 patients. During a mean follow-up of 10 years from the onset of the symptoms and 6 years from the EP testing, one patient died suddenly. He had stopped taking amiodarone 5 months before. In seven patients symptoms recurred and were due to discontinuation of therapy in two cases and inefficacy of previous effective treatment in five patients. After modification of the treatment (three cases), implantation of a pacemaker (one case) and catheter ablation (one case), all patients became asymptomatic. Eleven patients became asymptomatic with the first administered antiarrhythmic therapy. One patient continues to be asymptomatic in spite of discontinuation of his medical therapy. We conclude that patients with VT and no detectable heart disease have a good long-term prognosis and that appropriate therapy can be found in almost all patients. 相似文献