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Norberto Adame Jr. MD Bruce T. Horwood MD Daniel Caruso MD Ted Wallace MD Louis Velasco MD 《Academic emergency medicine》2006,13(1):114-116
Objectives: To determine whether the Mac‐technique test can detect kinking of the chest tube upon thoracostomy tube placement. Methods: This was a prospective observational study that was conducted October 2000 through October 2001 in an urban Level 1 trauma center. There were 103 consecutive nonrandomized adult trauma patients who required immediate tube thoracostomy during their initial resuscitation who were entered into the study. The Mac‐technique test was performed during standard tube thoracostomy insertion to the appropriate depth. The test involved grasping the external portion of the thoracostomy tube, turning it clockwise 180°, and then releasing the tube. If the tube spontaneously spun back to its original position, the test was considered positive, and the tube was considered kinked. If the tube did not spontaneously spin back and stayed in position upon release, the test was considered negative. Regardless of the results of this test, the tube was secured, and a postprocedure chest radiograph was obtained. The criterion standard for determining a kinked chest tube was its appearance on this chest radiograph. Results: A total of 103 chest tubes were placed by using the Mac‐technique test. The test was positive in eight placements; four tubes were kinked on chest radiograph. The Mac‐technique test was negative in 95 placements; four tubes were kinked on chest radiograph. The Mac technique had a sensitivity of 50% (95% confidence interval [CI] = 15.7% to 84.3%), a specificity of 95.8% (95% CI = 89.6% to 98.8%), a positive likelihood ratio of 11.9, a negative likelihood ratio of 0.52, and an odds ratio using Yates correction of 20.3 (95% CI = 4.1 to 102.1). Conclusions: On the basis of this study, a positive Mac‐technique test is useful to detect chest tubes that are likely to be kinked after insertion and before securing. 相似文献
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Obesity is the most important risk factor associated with non-alcoholic steatohepatitis, which is caused by to impaired insulin activity, overflow of portal triglycerides, and production of inflammatory cytokines; all of these are deleterious to hepatocytes. These phenomena facilitate disruptions in hepatic physiology, as observed in alcoholic hepatitis; however, consumption of this substance is absent. Non-alcoholic steatohepatitis has had a great impact due to the fact that previously, main cases of cryptogenic cirrhosis actually were attributed to this disease. Despite advances in understanding the pathophysiologic process of the disease, there is no better treatment than weight reduction (a combination of diet and exercise). In this issue, we describe the most important topics with regard to non-alcoholic steatohepatitis and the obesity-related process. 相似文献
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L-arginine, the precursor of nitric oxide, abolishes the effect of estrogens on bleeding time in experimental uremia. 总被引:1,自引:0,他引:1
C Zoja M Noris D Corna G Viganò N Perico G de Gaetano G Remuzzi 《Laboratory investigation; a journal of technical methods and pathology》1991,65(4):479-483
We have reported previously that conjugated estrogens that are effective in shortening the prolonged bleeding time in uremic patients are also effective on bleeding time in a rat model of uremia. Using such a rat model we have recently demonstrated that nitric oxide (NO), an endothelium-derived vasodilator, is involved in mediating the bleeding tendency of uremia. With the present study we wanted to investigate whether conjugated estrogen mixture or its active component, 17 beta-estradiol, reduce uremic bleeding by interfering with the NO pathway. Our results showed that the shortening effect of conjugated estrogen and 17 beta-estradiol on bleeding time of uremic rats was completely reversed by giving the animals the NO precursor L-arginine, but not D-arginine, which is not a precursor of NO. Dexamethasone which at variance to progesterone inhibits the process of induction of NO-forming enzyme, shortened the prolonged bleeding time of uremic rats within 4 hours from injection. This effect was eliminated by L-arginine but not D-arginine administration. The glucocorticoid receptor antagonist cortexolone prevented the shortening of bleeding time induced by dexamethasone, suggesting that a receptor-mediated mechanism is involved in the hemostatic effect of dexamethasone as previously reported for estrogens. Unlike conjugated estrogens and dexamethasone, progesterone had no effect on bleeding time. All these findings would indicate that the effect of estrogens and dexamethasone on primary hemostasis in uremia might be mediated by changes in NO synthetic pathway. 相似文献
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Federica Ursi Simone Virga Gonzalo Garcìa-Espejo Norberto Masciocchi Antonino Martorana Francesco Giannici 《Materials》2022,15(23)
Layered TiS2 intercalated with linear alkylamines has recently attracted significant interest as a model compound for flexible n-type thermoelectric applications, showing remarkably high power factors at room temperature. The thermal and, particularly, environmental stability of such materials is, however, a still an open challenge. In this paper, we show that amine-intercalated TiS2 prepared by a simple mechanochemical process is prone to chemical decomposition through sulfur exsolution, and that the presence of molecular oxygen is likely to mediate the decomposition reaction. Through computational analysis of the possible reaction pathways, we propose that Ti-N adducts are formed as a consequence of amine groups substituting for S vacancies on the internal surfaces of the S-Ti-S layers. These findings provide insights for possible future applications of similar hybrid compounds as devices operating in ambient conditions, and suggest isolating them from atmospheric oxygen. 相似文献
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Gabriela Datsch Bennemann Emilia Addison Machado Moreira Leticia Cristina Radin Pereira Maiara Brusco de Freitas Diane de Oliveira Julia Carvalho Ventura Eduardo Benedetti Parisotto Yara Maria Franco Moreno Erasmo Benicio Santos Moraes Trindade Eliana Barbosa Norberto Ludwig Neto Danilo Wilhelm Filho 《The clinical respiratory journal》2022,16(6):475
IntroductionOxidative stress (OS) occurs in cystic fibrosis (CF).ObjectiveThe objective of this work is to evaluate the influence of bacterial infection on biomarkers of OS (catalase [CAT], glutathione peroxidade [GPx], reduced glutathione [GSH]), markers of oxidative damage (protein carbonyls [PC], thiobarbituric acid reactive substances [TBARS]), together with the nutritional status and lung function in children with CF.MethodsCross‐sectional study including CF group (CFG, n = 55) and control group (CG, n = 31), median age: 3.89 and 4.62 years, respectively. CFG was distributed into CFG negative bacteriology (CFGB−, n = 27) or CFG positive bacteriology (CFGB+, n = 28), and CFG negative Pseudomonas aeruginosa (CFGPa−, n = 36) or CFG positive Pseudomonas aeruginosa (CFGPa+, n = 19).ResultsCompared with CG, CFG (P = .034) and CFGB+ (P = .042) had lower body mass index‐for‐age z‐score; forced expiratory volume in the first second was lower in CFGB+ and CFGPa+ (both P < .001). After adjusting for confounders and compared with CG: CFG showed higher TBARS (P ≤ .001) and PC (P = .048), and lower CAT (P = .004) and GPx (P = .003); the increase in PC levels was observed in CFGB+ (P = .011) and CFGPa+ (P = .001) but not in CFGB− (P = .510) and CFGPa− (P = .460).ConclusionsThese results indicate a systemic OS in children with CF. The presence of bacterial infection particularly Pseudomonas aeruginosa seems to be determinant to exacerbate the oxidative damage to proteins, in which PC may be a useful biomarker of OS in CF. 相似文献