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51.
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A modern concept of cost-effective digital signal processing hardware for measuring and analysing data from experiments investigating turbulent two-phase flows is presented. Using an array processor together with an appropriate analog-to-digital converter, conventional turbulence characteristics such as turbulence spectra, correlation functions, turbulence intensities and — scales can be evaluated in real time. 相似文献
53.
C Kü?ükhüseyin C Silan N Akba? M Payat H Oncel A Barlas 《Canadian Metallurgical Quarterly》1997,8(4):287-299
The effect of adenosine on pulmonary vessels was studied in isolated perfused rat lungs. Drugs were administered intra-arterially in a fixed volume of 0.1 ml Krebs solution as bolus injections. Adenosine responses were obtained before and 10 min after drug injections. When applied in logarithmically increasing doses (1-100 micrograms/ml), adenosine caused dose-dependent increases in pulmonary perfusion pressure (e.g. pulmonary vasoconstriction) which were readily reversible. Challenging adenosine with quinidine, dihydroergocristine and cyproheptadine (2 micrograms/ml each) did not significantly alter adenosine responses. Pretreatment of lungs with 0.5 mM theophylline, 10 micrograms/ml indomethacin, 30 micrograms/ml tebokan (a PAF antagonist) or 1 microgram/ml methylene blue for 10 min, however, antagonized the vasoconstrictor effect of the drug significantly. From these experiments, it was concluded that the mechanisms underlying the pulmonary vasoconstrictor action of adenosine are complex, and that both types of purinoceptors, prostaglandins, PAF and other vascular endothelial hormones might be involved. 相似文献
54.
F. Müller 《Journal of Phase Equilibria》1994,15(3):285-294
Methods and equipment successfully employed in high- temperature calorimetry to measure partial and integral enthalpies of
mixing in liquid oxide systems are reviewed with special attention given to the drop-mixing method. This technique has been
used to measure enthalpies of mixing in binary liq-uid mixtures composed of network forming oxides (e.g. SiO2) and network modifying oxides (e.g. Na2O). Results for the systems Na2O-SiO2 and Na2O- B2O3 are presented graphically. Entropies of mixing were estimated by combining enthalpies with available data on Gibbs energies
of mixing. Prominent thermochemical features of glass-forming oxide melts are pointed out. The observed thermodynamic behavior
is discussed in relation to its structural basis. 相似文献
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A flow-cytometric method with fluorescence-labeled monoclonal antibodies (MABs) against the low density lipoprotein (LDL) receptor (C7A MAB) or 3,3'-dioctadecylindocarbocyanin-iodide (DiI) LDL has been developed that allows the quantification of LDL receptors on leukocytes and the identification of patients with familial hypercholesterolemia (FH) within 48 hours. Leukocytes were isolated from 10 mL anticoagulated blood by density gradient centrifugation. To induce maximal expression of LDL receptors, mononuclear cells were preincubated with either phytohemagglutinine (PHA) or lipoprotein-deficient serum (LPDS). LPDS-treated monocytes provided a more homogeneous cell population with regard to LDL receptor activity than did the PHA-treated lymphocytes; they also provided a greater discrimination between the fluorescence of the receptor probes and cellular autofluorescence. The C7A MAB was able to compete for DiI LDL binding by about 40%. In competition with unlabeled LDL, DiI LDL revealed linear binding, indicating an affinity similar to native LDL. The binding characteristics of DiI LDL were also similar to 125I-LDL binding. LDL isolated from familial defective apolipoprotein B-100 was not able to compete for DiI LDL binding on monocytes, whereas native LDL reduced it by about 80%. In monocytes from FH heterozygous patients, the cellular mean fluorescence using either C7A MAB or DiI LDL at 4 degrees C was 30% to 70%; in FH homozygotes, cellular mean fluorescence was less than 20% of that in monocytes from normal individuals. In patients with familial defective apolipoprotein B-100 antibody binding was normal, but one patient's own LDL failed to compete with normal DiI LDL for 4 degrees C binding on U937 test monocytes. Patient monocytes having internalization defects showed normal 4 degrees C DiI LDL binding, but at 20 degrees C cell-associated fluorescence was reduced by about 40%. In our study 384 hypercholesterolemic patients (preselected according to serum cholesterol levels, clinical symptoms, and family history) were analyzed for LDL receptor expression using the C7A MAB-based assay. In 71.8% of the patients with cholesterol levels higher than 300 mg/dL, an LDL receptor deficiency was observed. Apolipoprotein E isoforms and lipoprotein[a] were found to be independent from the LDL receptor status. In some patients with high cholesterol levels but normal LDL receptor expression with the C7A MAB assay, LDL receptor defects could be diagnosed when either reduced binding or internalization of DiI LDL or familial defective apolipoprotein B-100 was detected.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
60.
The properties of interpersonal verbs (e.g., help, dislike, etc.) that systematically influence "implicit causality" are analyzed in 3 studies. It is argued that interpersonal verbs have a set of properties (multiple inference-inviting properties [MIIPs]) that are differentially elicited as a function of the type of property primed by the type of inference request. Study 1 distinguishes event instigation as a property that is systematically influenced by verb type: Action verbs induce subject inferences, and state verbs induce object inferences. Study 2 shows that dispositional inferences are mainly mediated by action verbs and the referentiality (sentence subject or object) of adjectives that are morphologically derived from verbs. Study 3 shows that studies of implicit causality have confounded event instigation and dispositional inferences in their operationalizations and Study 3 suggests that inferences of dispositionality and event instigation are orthogonal factors contributing differentially to what has to date been referred to as "implicit causality." The implications of these findings are discussed in terms of the interface between language and social cognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献