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151.
X Sáez-Llorens MS Ah-Chu E Casta?o L Cortés A Torres M Suárez A Bissot W Reyes WB Karp GH McCracken 《Canadian Metallurgical Quarterly》1995,21(4):876-880
Because of high rates of neonatal gram-negative sepsis in many Latin American countries, we prospectively enrolled 784 high-risk pregnant women in a study designed to evaluate the effect of a single 1-g dose of ceftriaxone (n = 390) vs. that of no antibiotic prophylaxis (n = 394) on oral, rectal, and umbilical colonization and fatality rates among newborn infants. The mean ceftriaxone concentration in cord blood samples was 26 microgram/mL (range, 9-40 microgram/mL). Compared with infants of untreated mothers, children born to women who were given ceftriaxone were colonized at a lesser rate by gram-negative bacilli (54% vs. 35%; P < .001) and by group B streptococci (54% vs. 21%; P = .03) and endured significantly fewer sepsis-like illnesses in the first 5 days of life (8.1% vs. 3.1%; P = .004). There was also a tendency for them to have fewer episodes of culture-proven early-onset sepsis (2.8% vs. 0.5%; P = .06). Sepsis-related case-fatality rates (0.8% and 0.3%, respectively) were not significantly different. Although intrapartum administration of a single dose of ceftriaxone to high-risk mothers could be a safe and potentially useful strategy for reducing early-onset neonatal infections, additional information is required before this approach can be recommended for routine prophylaxis. 相似文献
152.
153.
N Gascón C Otal C Martínez-Brú J Mercé M Cortés R Arcelus JM Queraltó JM Sánchez F González-Sastre 《Canadian Metallurgical Quarterly》1993,39(6):1033-1036
We studied the effect in vitro and in vivo of dipyrone on the determination of several biochemical tests in two analyzers, a Hitachi 747 and a Kodak Ektachem 700. From studies in vitro, we found significant interference by dipyrone (P < 0.05) in the determination of creatine kinase (CK), lactate dehydrogenase (LD), uric acid, triglycerides, cholesterol, aspartate aminotransferase, alanine aminotransferase, and urea nitrogen with both instruments, and in the determination of creatinine in the Ektachem analyzer. We also studied the effect of intravenously administered dipyrone in 14 patients. Dipyrone interfered significantly (P < 0.05) in the determination of CK, LD, uric acid, triglycerides, and cholesterol with both instruments, and creatinine only with the Ektachem analyzer. Using high-performance liquid chromatography (HPLC), we measured concentrations of dipyrone in the serum of patients who had received the drug and observed a negative correlation between the concentrations of dipyrone in the blood and the percentage of each analyte concentration. 相似文献
154.
OBJECTIVE: Recent clinical studies suggest that the reflex increase in sympathetic nervous activity accompanying a reduction in blood pressure may contribute to the untoward effects of dihydropyridine calcium antagonists. The aim of this study was to examine whether plasma noradrenaline levels and renin activity are increased with the reduction of blood pressure during the initial phase of administration of the long-acting dihydropyridine calcium antagonist amlodipine. METHODS: The effects of amlodipine on ambulatory blood pressure and on diurnal variations in plasma noradrenaline and renin activity were examined 1, 4, and 7 days after the start of amlodipine administration in eight inpatients with essential hypertension. RESULTS: The 24-h mean systolic and diastolic blood pressure on day 7 was significantly lower than it was 1 day before the start of treatment. There was no change in the mean heart rate. The mean trough to peak ratios of systolic and diastolic blood pressure of seven patients were 61% and 71%, respectively. Diurnal patterns of plasma noradrenaline levels and renin activity 1, 4, and 7 days after the start of amlodipine administration were unchanged. CONCLUSION: The antihypertensive effects of amlodipine were of slow onset and long duration and were not accompanied by an increase in sympathetic activity or activation of the renin-angiotensin system. 相似文献
155.
R Otero-Candelera A Cayuela Domínguez M Arenas A Segado Soriano E Barrot Cortés A Verano Rodríguez 《Canadian Metallurgical Quarterly》1997,33(3):118-123
A review of anthropological, sociological, and psychological theories of suicidal behavior indicates that a disruption in social relationships and a breakdown in community networks increase the risk of suicide. Current suicide prevention tactics fail to address these problems, and suggestions are made for tactics that would focus on the underlying causes of suicide, tactics consistent with a communitarian philosophy and tactics that could guide us into the 21st century. 相似文献
156.
This paper introduces a novel continuous‐time dynamic average consensus algorithm for networks whose interaction is described by a strongly connected and weight‐balanced directed graph. The proposed distributed algorithm allows agents to track the average of their dynamic inputs with some steady‐state error whose size can be controlled using a design parameter. This steady‐state error vanishes for special classes of input signals. We analyze the asymptotic correctness of the algorithm under time‐varying interaction topologies and characterize the requirements on the stepsize for discrete‐time implementations. We show that our algorithm naturally preserves the privacy of the local input of each agent. Building on this analysis, we synthesize an extension of the algorithm that allows individual agents to control their own rate of convergence towards agreement and handle saturation bounds on the driving command. Finally, we show that the proposed extension additionally preserves the privacy of the transient response of the agreement states and the final agreement value from internal and external adversaries. Numerical examples illustrate the results. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
157.
V. Cortés J. Blasco N. Aleixos S. Cubero P. Talens 《Food and Bioprocess Technology》2017,10(10):1755-1766
Visible and near-infrared spectroscopy has been widely used as a non-invasive and rapid-assessment technique for the quality control of agricultural products. In this study, 325 samples of nectarines representing two commercial varieties, cv. ‘Big Top’ and cv. ‘Magique’, were analysed by visible and near-infrared diffuse reflectance spectroscopy (VIS-NIR). The spectral data were pre-treated and analysed to predict the internal quality of the samples and to discriminate between the two varieties. Good prediction of the internal quality of the samples, using partial least-squares regressions, was observed for both (R 2 P of 0.909 and 0.927 and RMSEP of 0.235 and 0.238 for cv. Big Top and Magique, respectively). Discriminant models, using linear discriminant and partial least-squares discriminant analyses, were built to classify the nectarines. Both methods provided good results with rates of 97.44 and 100% of correctly classified samples. The results indicated that visible and near-infrared techniques can be useful and simple methods for quality control and for the correct identification of nectarines in commercial lines as an alternative to the slower and less accurate manual classification. 相似文献
158.
Kevin Neumann Sarthak Jain Alessia Gambardella Dr. Sarah E. Walker Dr. Elsa Valero Dr. Annamaria Lilienkampf Prof. Mark Bradley 《Chembiochem : a European journal of chemical biology》2017,18(1):91-95
Molecules that undergo activation or modulation following the addition of benign external small‐molecule chemical stimuli have numerous applications. Here, we report the highly efficient “decaging” of a variety of moieties by activation of a “self‐immolative” linker, by application of water‐soluble and stable tetrazine, including the controlled delivery of doxorubicin in a cellular context. 相似文献
159.
Stigler Rolf-Dietrich; Ruker Florian; Katinger Dietmar; Elliott Graham; Hohne Wolfgang; Henklein Peter; X.Ho Joseph; Keeling Kim; Carter Dan C.; Nugel Elsa; Kramer Achim; Porstmann Tomas; Schneider-Mergener Jens 《Protein engineering, design & selection : PEDS》1995,8(5):471-479
The molecular interaction of the Fab fragment of the human monoclonalantibody 3D6, directed against the transmembrane protein gp41of human immunodeficiency virus (HTV) 1, with its peptide epitopeis characterized by a panel of overlapping peptides, a peptideepitope library and molecular modeling techniques. The sequenceCSGKLICTTAVPW, corresponding to amino acids 605617 ofgp41, was identified as the best binding peptide (KD = 1x10-8mol/1). This peptide served as a starting point to prepare acellulose-bound peptide epitope library in which each residueof the epitope is substituted by all L- and D-amino acids, resultingin 494 epitope peptide variants which were subsequently analyzedfor binding 3D6. The library was synthesized to identify residuescritical for binding and to obtain information about the molecularenvironment of the epitope peptide bound to 3D6. Both cysteineresidues, as well as isoleucine 6, threonine 8 and proline 12,of the epitope were highly sensitive to substitution. Usingthe data obtained from the epitope characterization, as wellas a low-resolution electron density map of a 3D6 Fab-peptidecomplex, a 3-D model of the Fab-peptide complex was generatedby molecular modeling. The modeling experiments predict bindingof the peptide, which is cyclized via the two cysteine residues,to a pocket formed dominantly by the hypervariable loops complementaritydetermining regions CDR3L, CDR2H and CDR3H. 相似文献
160.