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排序方式: 共有87条查询结果,搜索用时 15 毫秒
1.
From 1988 to 1995, 96 patients (161 feet) underwent a modified Mitchell distal metatarsal osteotomy performed for mild-to-moderate hallux valgus. On AP x-rays of the standing foot, the average intermetatarsal angle was corrected from 15 degrees to 9 degrees, and the first metatarsophalangeal angles were corrected from an average of 41 degrees to 15 degrees. Criteria for evaluation of clinical results included relief of pain, appearance of foot, and shoe wear. After an average follow-up of 38 months, the overall satisfaction rate was 92.5%. Complications included 13 pin tract infections, two delayed unions, and two correction losses. The most common late sequela was transfer metatarsalgia of the lesser toes, which occurred in 20 feet (12.4%), leading to some dissatisfaction. The Mitchell osteotomy can be used on cases with less than 20 degrees of intermetatarsal angle, offering a stable construct with easy postoperative care.  相似文献   
2.
Subchronic intoxication was induced in outbred male rats by repeated intraperitoneal injections with lead oxide (PbO) and/or cadmium oxide (CdO) nanoparticles (NPs) 3 times a week during 6 weeks for the purpose of examining its effects on the contractile characteristics of isolated right ventricle trabeculae and papillary muscles in isometric and afterload contractions. Isolated and combined intoxication with these NPs was observed to reduce the mechanical work produced by both types of myocardial preparation. Using the in vitro motility assay, we showed that the sliding velocity of regulated thin filaments drops under both isolated and combined intoxication with CdO–NP and PbO–NP. These results correlate with a shift in the expression of myosin heavy chain (MHC) isoforms towards slowly cycling β–MHC. The type of CdO–NP + PbO–NP combined cardiotoxicity depends on the effect of the toxic impact, the extent of this effect, the ratio of toxicant doses, and the degree of stretching of cardiomyocytes and muscle type studied. Some indices of combined Pb–NP and CdO–NP cardiotoxicity and general toxicity (genotoxicity included) became fully or partly normalized if intoxication developed against background administration of a bioprotective complex.  相似文献   
3.
Mass eutrophication of microalgae and cyanobacteria is observed in Lake Baikal in the past decade. In this paper, the concept of replaceable adsorption filter material based on chitosan flocculant filler and chlorinated polyvinyl chloride polymer nonwoven material are proposed. Functional and mechanical properties and morphology of the material are investigated depending on a packing density and a degree of chitosan filling. The introduction of 45% chitosan increases the Young's modulus up to 10 times, and it makes the material more rigid in 2.8 times. The high efficiency of sorption and growth inhibition of cumulative biomass culture was shown. The biomass source is taken from the coast of Barguzinsky Bay of Lake Baikal. Dominant species is microalgae of Scenedesmus genus.  相似文献   
4.
Electropolymerizing the prosthetic group (flavin adenine dinucleotide, FAD) responsible in the active sites of dehydrogenases for NAD(+)|NADH regeneration, we succeeded in mimicking enzyme activity. Poly(FAD) characterized by an additional polymer-type redox reaction has been discovered as a highly effective electrocatalyst for NADH oxidation: operating at the lowest potentials reported for NADH transducers (0.00 V, pH 7.4), poly(FAD) is characterized by the electrochemical rate constant of 1.8 +/- 0.6 x 10(-3) cm s(-1), which is at the level of the NADH mass-transfer constant. Flow injection analysis of NADH with the poly(FAD)-modified wall-jet electrode as a detector has been characterized by a linear calibration range prolonged down to 5 x 10(-7) M and a sensitivity of 0.08 A M(-1) cm(-2), which taking into account the dispersion coefficient ( approximately 3), is at the diffusion-limiting value. In contrast to the low molecular weight mediators able to exhibit similar electrocatalytic properties, poly(FAD)-modified electrodes are characterized by the dramatically improved stability and, thus, can be considered as the most advantageous NADH transducers for analytical chemistry.  相似文献   
5.
Alpha quartz     
Ramus  R. 《Potentials, IEEE》1989,8(4):9-12
The history of the use of alpha quartz, SiO2, one of the nine forms of silica is sketched, and its structure and crystallography are described. Piezoelectricity, the most important property of quartz from an electrical standpoint, is explained. Processing of quartz crystals to ensure proper operation in circuits is discussed. The two primary types of device made from quartz crystal plates or wafers, the quartz crystal resonator and the quartz transducer, are described  相似文献   
6.
Colloid systems modified by luminescent ions in situ are highly attractive for the design of new molecular architectures and adaptable for monitoring and visualizing soft drug delivery systems. This paper presents original results on the characterization of the self‐organization process and the structure of vesicles formed by tetraethylene glycol monodecyl ether (C12EO4) in the presence of lanthanide ions and decanol additives. Detailed characterization of surface activity, aggregation properties and microstructure of individual and mixed aggregates has been carried out based on surface tension, electron microscopy, small‐angle X‐ray scattering, dynamic light scattering analysis and fluorescence spectroscopy. The small‐angle scattering results in combination with quantum‐chemical calculations assume the multishell vesicle formation in C12EO4/C10H21OH/H2O media. In the C12EO4 solution the presence of Ln(III) ions and decanol initiate the formation of multilamellar vesicles with a size of about 100 nm. The luminescence analysis of the Eu(III) and Tb(III) complexes has shown the efficient solubilization in the C12EO4/C10H21OH/H2O vesicles, which leads to increase in the lifetime. The resulting outcome is the possibility to control micro and macro properties of a molecular organized system to give it the desired functionality.  相似文献   
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Abstract

The influence of depressant and depressant-dispersing additives injection in the amount of less than 0.75% on low-temperature properties of marine fuels and their distillate compounds is presented in this research paper. As tested components were used the following industry-derived components: hydrotreated straight-run diesel fraction (HSRDF), ultra-low sulfur content hydro-creaking diesel fuel (ULSDH), light gas oil delayed coking and light gas oil catalytic creaking (LGODC and LGOCC), light vacuum gas oil (LVGO) and visbreaker residue (VR). As marine fuels samples the compounds based on described above components were used. The influence of the following additives was studied: SEVILEN 11606-40, KOLTEK DN 3149, Dodiflow 5934 and DPN-172.  相似文献   
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