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991.
Current recommendations advocate that blood tubes for coagulation testing should be filled not less than 90% of their nominal filling volume, since under- or over-filling >10% may generate unreliable results of some hemostasis assays. This study was hence aimed to explore filling accuracy and precision of commercial blood tubes. Between-lot variations of 3 different lots (20 tubes per lot) of 3.2% citrate blood tubes manufactured by Becton Dickinson, Greiner and Kima were studied. One additional lot from each manufacturer was assessed in triplicate (three series of 20 tubes), to assess within-lot variation. All tubes were first weighed empty and then filled with distilled water by a syringe, under ideal filling conditions. Filled tubes were weighed again, in duplicate. For each 20 tubes series, mean bias (deviation from the ideal tube filling volume) and imprecision (coefficient of variation; CV%) were calculated. All biases were within ±10%. Within-lot and between-lot variation in filling volume was acceptable, and comprised between 0.4 and 2.4%. Greiner tubes were the most accurate (bias, ?1.0 to 2.4%), followed by Kima (bias, ?7.8 to ?5.9%) and Becton Dickinson (bias, ?9.6 to 3.3%) tubes. The highest between-lot difference was noted for Becton Dickinson tubes (up to 12.9%), followed by Greiner and Kima tubes (up to 3.4 and 1.8%, respectively). Although coagulation tubes filling accuracy was within ±10% for all three tested manufacturers, the overall bias was found to be variable among manufacturers and lots. Major effort shall be made by blood tube manufacturers for improving standardization of their products.  相似文献   
992.
Coronary disease is a common condition in patients affected by heart failure with severely reduced ejection fraction (HFrEF). This condition represents an indication for implantable cardioverter defibrillator (ICD) in order to reduce the risk of sudden death related to arrhythmias. Nevertheless, inappropriate shocks are associated with worse quality of life, hospitalization, and death. We present the case of an inappropriate shock related to percutaneous coronary intervention during the insertion and advancement of the guidewire into the left anterior descending artery (LAD) in a patient with an ICD. Physicians’ awareness about the clinical implication of noise arising during a coronary procedure is very important in patients with an ICD or pacemaker, to avoid inappropriate shock or pacing inhibition and to raise the possibility of lead implantation in or helix protrusion into the coronary lumen.  相似文献   
993.
994.
Erythropoiesis is triggered by hypoxia and is strictly regulated by hormones, growth factors, cytokines, and vitamins to ensure an adequate oxygen delivery to all body cells. Abnormalities in one or more of these factors may induce different kinds of anemia requiring different treatments. A key player in red blood cell production is erythropoietin. It is a glycoprotein hormone, mainly produced by the kidneys, that promotes erythroid progenitor cell survival and differentiation in the bone marrow and regulates iron metabolism. A deficit in erythropoietin synthesis is the main cause of the normochromic normocytic anemia frequently observed in patients with progressive chronic kidney disease. The present review summarizes the most recent findings about each step of the erythropoietic process, going from the renal oxygen sensing system to the cascade of events induced by erythropoietin through its own receptor in the bone marrow. The paper also describes the new class of drugs designed to stabilize the hypoxia-inducible factor by inhibiting prolyl hydroxylase, with a discussion about their metabolism, disposition, efficacy, and safety. According to many trials, these drugs seem able to simulate tissue hypoxia and then stimulate erythropoiesis in patients affected by renal impairment. In conclusion, the in-depth investigation of all events involved in erythropoiesis is crucial to understand anemia pathophysiology and to identify new therapeutic strategies, in an attempt to overcome the potential side effects of the commonly used erythropoiesis-stimulating agents.  相似文献   
995.
996.
In this study, we evaluated immunocytochemical staining for milk proteins (alpha-lactalbumin and beta-lactoglobulin) in tracheal aspirates of mechanically ventilated infants, and assessed whether this staining technique supported a clinical diagnosis of aspiration in infants receiving orogastric feedings. All newborns requiring mechanical ventilation in the neonatal intensive care unit of a major tertiary care hospital were potential subjects for this study. Tracheal aspirates were obtained prior to the introduction of enteral feeding and at various time points thereafter in newborns requiring mechanical ventilation. Cells were obtained and processed for immunocytochemical staining of alpha-lactalbumin and beta-lactoglobulin. In total, 88 specimens recovered from 34 infants were adequate for staining. Alveolar macrophages recovered from most of the infants who were never fed (true negative controls) did not display immunoreactivity for milk proteins: 4/34 or 12% of infants' aspirates demonstrated presence of milk proteins before enteral feeding was commenced. Tracheal aspirates obtained from 12 infants after introduction of enteral feedings appeared to support clinical and radiological findings suggestive of aspiration events, with positive immunostaining on several occasions. These observations support our work in a murine model and demonstrate that immunocytochemical staining of tracheal aspirates for milk proteins may enhance the ability to diagnose pulmonary aspiration. Further studies are needed to define the clinical significance of our findings and the effects of single and repeated aspiration events on respiratory status.  相似文献   
997.
Thrombotic thrombocytopenic purpura (TTP) is a rare disorder of small vessels that is associated with deficiency of the von Willebrand factor-cleaving protease, ADAMTS13. The presence of anti-ADAMTS13 autoantibodies is considered a factor predisposing to relapses. Despite close monitoring and intensive plasma treatment, in these patients acute episodes are still associated with substantial morbidity and mortality rates, and the optimal therapeutic option should be prevention of relapses. This study was conducted in a patient with recurrent TTP due to high titers of ADAMTS13 inhibitors, who used to have 2 relapses of TTP a year. The study compared the standard treatment plasma exchange with rituximab. Results documented that plasma exchange had only a small transient effect on ADAMTS13 activity and inhibitors; on the contrary, prophylaxis with rituximab was associated with disappearance of anti-ADAMTS13 antibodies, a progressive recovery of protease activity, and it allowed the patient to maintain a disease-free state during a more than 2-year follow-up.  相似文献   
998.
999.
BACKGROUND: The use of abciximab (c7E3 Fab; ReoPro , Eli Lilly & Company, Indianapolis, Indiana) during percutaneous coronary intervention (PCI) decreases the incidence of early (30-day) and late (6-month to 1 year) adverse cardiac ischemic events. In a high-risk population, abciximab also reduced the need for target lesion revascularization. PCI of lesions with complex morphology, particularly long lesions, is associated with more complicated outcomes. The use of multiple and/or long intracoronary stents to cover long coronary lesions may lower the incidence of acute or subacute occlusion, but is still limited by a high late restenosis rate. We characterized patients undergoing elective implantation of long or multiple overlapping coronary stents and determined the impact of abciximab administration on clinical and angiographic outcomes. METHODS AND RESULTS: In a prospective, single-center randomized trial, a total of 107 patients undergoing elective implantation of long or multiple overlapping coronary stents were randomly assigned to receive either standard-dose heparin (n = 53) or abciximab plus low-dose heparin (n = 54). The use of abciximab was not associated with an increased incidence of bleeding or vascular complications compared to standard heparin regimen (3.7% versus 3.8%, respectively; p = NS). A 68% reduction in composite in-hospital cardiac events (i.e., death, myocardial infarction, urgent revascularization) was observed in the abciximab group (3.7% versus 11.5%, p = 0.1). At 6-month follow-up, a 48% reduction of target lesion revascularization (11% versus 21%; p = 0.1) and a decrease in binary angiographic restenosis were observed for abciximab-treated patients (17% versus 34%; p < 0.05). CONCLUSION: The peri-procedural use of abciximab during implantation of long or multiple overlapping coronary stents is safe and effective, as it does not increase bleeding or vascular complications compared to standard heparin anticoagulation and reduces the incidence of in-hospital adverse cardiac events; moreover, abciximab improves 6-month clinical and angiographic outcomes in such a complex setting.  相似文献   
1000.
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