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81.
82.
The investigators designed this validation study to determine the defining characteristics of the nursing diagnosis ineffective airway clearance. Using Fehring's Diagnostic Content Validity Model, 546 nurses who care for respiratory clients validated one major and 19 minor defining characteristics. Nine characteristics previously described in the literature were eliminated. Clarification of the defining characteristics of this diagnosis improves communication in practice, education and research.  相似文献   
83.
Book Review     
Performance Breakthroughs for Adolescents With Learning Disabilities or ADD. G. Markel & J. Greenbaum.  相似文献   
84.
Protocols for dipyridamole stress testing have evolved in the last 16 years in the neverending quest of optimal diagnostic accuracy and user friendliness. Higher dipyridamole dose in a shorter infusion time provides higher sensitivity, but concern over safety is still controversial. An accelerated high-dose (0.84 mg/kg in 6 minutes without atropine) dipyridamole stress test was performed on 1,295 patients in 2 echocardiographic laborotories: Institute of Clinical Physiology of Pisa and Niguarda Hospital of Milan. During testing, there were no deaths and no patients had ventricular fibrillation. Major adverse reactions occurred in 3 cases (1 every 431 studies): 1 myocardial infarction, 1 brief cardiac asystole, and 1 transient ischemic attack. Overall feasibility was 97%. In 66 patients with normal function at rest who were evaluated off therapy, with coronary angiography performed independently of test results, the accelerated high-dose protocol showed a sensitivity of 85% (confidence interval [CI] 73% to 92%) and a specificity of 93% (CI 83% to 97%) for angiographically assessed coronary artery disease (quantitatively assessed diameter reduction > or = 50%). Diagnostic accuracy of the accelerated high dose was 89% (CI 79% to 95%). Thus, accelerated high-dose dipyridamole stress echocardiography was reasonably safe and well tolerated. This protocol is especially appealing for its excellent diagnostic accuracy coupled with the short imaging time and no need for drug cocktails.  相似文献   
85.
Rodgers  GM; Greenberg  CS; Shuman  MA 《Blood》1983,61(6):1155-1162
The coagulant properties of intact bovine vascular cells (aortic endothelial and smooth muscle cells) and human vascular cells (cutaneous and foreskin microvascular cells, umbilical venous endothelium) grown in vitro were studied. Compared to nonvascular cells (fibroblasts, corneal endothelial cells, fetal lung or intestinal mucosal cells), vascular cells had little procoagulant activity. Radioimmunologic measurement of thrombin in recalcified plasma demonstrated markedly lower concentrations of thrombin in the presence of vascular endothelial and smooth muscle cells compared to corneal endothelial and fetal lung cells. The low thrombin concentrations were not a consequence of thrombin binding to the vascular cells nor were they due to accelerated thrombin inactivation by antithrombin-III or alpha 2-macroglobulin. Neither vascular cells nor the nonvascular cells promoted contact activation of plasma as measured by a sensitive specific assay for kallikrein. Studies with intact cell monolayers and purified factors VIIa and X indicated that while nonvascular cells express tissue factor activity, vascular cells do not exhibit this property. These data suggest that the nonthrombogenic nature of intact vascular cells is due to their failure to initiate contact activation and to express tissue factor activity. In addition, the primary difference in coagulant potential between vascular cells and nonvascular cells is the lack of tissue factor expression by the vascular cells.  相似文献   
86.
BackgroundThe incidence of myocardial injury (MI) in patients with COVID-19 in Brazil and the prognostic impact of MI have not been elucidated.ObjectivesTo describe the incidence of MI in patients with COVID-19 in the intensive care unit (ICU) and to identify variables associated with its occurrence. The secondary objective was to assess high-sensitivity troponin I as a predictor of in-hospital mortality.MethodsRetrospective, observational study conducted between March and April 2020 with cases of confirmed COVID-19 admitted to the ICU. Numerical variables were compared by using Student t test or Mann-Whitney U test. The chi-square test was used for categorical variables. Multivariate analysis was performed with variables associated with MI and p<0.2 to determine predictors of MI. The ROC curve was used to determine the troponin value capable of predicting higher in-hospital mortality. Survival functions were estimated by use of the Kaplan-Meier method from the cut-off point indicated in the ROC curve.ResultsThis study assessed 61 patients (63.9% of the male sex, mean age of 66.1±15.5 years). Myocardial injury was present in 36% of the patients. Systemic arterial hypertension (HAS) [OR 1.198; 95%CI: 2.246-37.665] and body mass index (BMI) [OR 1.143; 95%CI: 1.013-1.289] were independent risk predictors. High-sensitivity troponin I >48.3 ng/mL, which was determined in the ROC curve, predicts higher in-hospital mortality [AUC 0.786; p<0.05]. Survival in the group with high-sensitivity troponin I >48.3 ng/mL was lower than that in the group with values ≤48.3 ng/dL [20.3 x 43.5 days, respectively; p<0.05].ConclusionThere was a high incidence of MI in severe COVID-19 with impact on higher in-hospital mortality. The independent risk predictors of MI were SAH and BMI. (Arq Bras Cardiol. 2020; [online].ahead print, PP.0-0)  相似文献   
87.
88.
Marrow transplantation was attempted in a 13-yr-old boy with congenital hypoplastic anemia who had never responded to corticosteroid therapy. Prior to the transplant, he had received 238 transfusions, at least 12 of which were from his father. He was prepared for grafting with antilymphocyte globulin, procarbazine, and total body irradiation (1000 rads). The patient, whose red cells were Group B, then received marrow cells from his Group O, histocompatible, sister. Thereafter, reticulocytes, Group O erythrocytes, and female leukocytes appeared in the peripheral blood. Erythroid precursors were seen in the patient's marrow for the first time in his life, and all lacked fluorescent Y chromosomes. Dividing cells were all female. After initially progressing well, the patient developed interstitial pneumonia and died 55 days after the transplant. The successful erythroid graft suggested that this patient's failure to produce red blood cells was due to a defective stem cell rather than to a humoral defect, plasma inhibitor, or abnormal marrow microenvironment. It suggested further that sibling marrow may be engrafted in patients who have received multiple transfusions, even from a parent.  相似文献   
89.
The efficacy of DEB in modifying the high restenosis risk associated with BMS implantation is doubtful. Optical coherence tomography (OCT) may allow precise assessment of neointimal formation after stent implantation. We performed a single-center, prospective, 1:2 randomized trial comparing BMS implantation alone (BMS group) vs. additional DEB (DEB group). DEB patients were further randomized 1:1 to DEB before stenting (pre-DEB group), or after stenting (post-DEB group). Primary endpoint was OCT-assessed neointimal hyperplasia (expressed both as mean in-stent neointimal area and as percentage obstruction of the mean stent area) at 6 months. Secondary endpoints were the percentage of uncovered and malapposed stent struts. Thirty patients were enrolled and randomized to BMS (n = 10), pre-DEB (n = 10), post-DEB (n = 10). At 6-month OCT follow-up, DEB significantly reduced neointimal area compared with BMS: mean neointimal area 2.01 ± 0.89 vs. 3.03 ± 1.07 mm2 (p = 0.02), percentage area obstruction 24.56 ± 12.50 vs. 37.51 ± 12.26 % (p = 0.02). The percentage of uncovered and malapposed stent struts did not differ significantly between BMS and DEB. In the comparison between pre-DEB and post-DEB, no significant difference was observed for both primary and secondary endpoints. In de novo coronary lesions treated with BMS, DEB use could be associated with a mild reduction in neointimal hyperplasia at 6 months; this effect could be unrelated to the timing of DEB dilation (pre- or post-stenting).Clinical Trial Registration Information: http://www.clinicaltrials.gov. Identifier: NCT01057563.  相似文献   
90.
The immunophenotypes of lymphoblasts from children with newly diagnosed T-cell acute lymphoid leukemia (T-ALL, n = 101) or T-cell non-Hodgkin lymphoma (T-NHL, n = 31) were analyzed to correlate stage of thymocyte differentiation with clinical features and outcome. The 67 boys and 34 girls with T-ALL were 1 month to 18 years old (median, 8 years) with leukocyte counts ranging from 2 to 810 x 10(9)/L (median, 55 x 10(9)/L). Eighteen of these patients were black, and 70 had a mediastinal mass. Twenty-six boys and five girls with a median age of 9 years (range, 1 to 20 years) had T-NHL. Seven of these patients were black, and 24 had a mediastinal mass. The distributions of thymocyte developmental stages (early [CD7+], intermediate [CD1+ and/or CD4+ and/or CD8+], and mature [CD3+]) in cases of T-ALL and T-NHL were significantly different: 34%, 43%, and 23% v 6%, 62%, and 32% (P = .02). A comparison of the patients' clinical features according to the maturational stage of thymocytes failed to disclose significant differences in the majority of characteristics studied. However, patients with mature-stage T-NHL, with or without the addition of subjects with mature-stage T-ALL, were less likely to have a mediastinal mass (P = .02 for both comparisons). Those with intermediate-stage T-cell malignancy (T-ALL and T-NHL combined) were the subgroup most likely to have a mediastinal mass (P = .01). Response to remission induction therapy was significantly worse in the T-ALL subgroup with an early-stage phenotype: a failure rate of 21% v 0% and 6% for the two more differentiated phenotypic subgroups (P = .007). Event-free survival was not affected by thymocyte maturational stage in cases of either T-ALL or T-NHL. Despite evidence of clinical heterogeneity among the maturational stages of T-cell malignancies in children, these developmental subdivisions do not appear to be critical determinants of outcome once remission is achieved. We conclude that such phenotypes need not be included in the stratification plans for clinical trials using common induction treatment.  相似文献   
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