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201.
VP Kushner AB Grandilevskaia AA Klimova GI Blinova VA Ivanov 《Canadian Metallurgical Quarterly》1996,38(6):596-599
BACKGROUND: Gastrointestinal myoelectric activity during postoperative ileus has been well characterized. However, the common clinical scenario of ileus occurring during and after episodes of sepsis is not well understood. The aim of our study was to determine the effects of a single, sublethal dose of endotoxin on canine gastrointestinal myoelectric activity. METHODS: Eight dogs underwent placement of serosal electrodes on the stomach and small intestine and insertion of a jejunal cannula. After the animals recovered, electrical activity and jejunal mucosal blood flow were determined during fasting and with feeding. Following completion of these baseline studies dogs were given a single, sublethal dose of Escherichia coli lipopolysaccharide (200 g/kg) intravenously, and the studies were repeated daily for 3 consecutive days. RESULTS: Endotoxin resulted in an absence of the interdigestive migrating myoelectric complex for 2 days, a decrease in duodenal and jejunal action potentials during fasting and with feeding, but no decreases in jejunal mucosal blood flow. The gastrointestinal myoelectrical patterns returned to those found in health on postendotoxin day 3. CONCLUSIONS: A single, sublethal dose of endotoxin results in a temporary disruption of gastrointestinal myoelectric activity similar to that seen during postoperative ileus. The etiology of this "adynamic" ileus is unknown but does not appear to be secondary to intestinal ischemia. 相似文献
202.
The sensitivity of various criteria of the physical exercise test in revealing myocardial ischemia was studied in 2 groups of patients with ischemic heart disease: 1st group of 64 patients with normal ECG at rest, 2nd group of 96 patients with cicatricial changes in the myocardium. Selective coronography demonstrated atherosclerotic narrowing (stenosis of more than 70%) of one or more coronary arteries of the heart in all patients. During physical exercise an attack of angina pectoris without "ischemic" changes on the ECG occurred in 36.1% of patients of the 1st group and in 22.4% of patients of the 2nd group. The frequency of other clinical signs of cessation of the exercise (dyspnoea, change of arterial pressure, extrasystole and others) was three and a half times higher in patients with cicatricial changes in the myocardium. It is concluded that the frequency with which signs of myocardial ischemia are revealed during physical exercise depends not only on the pronounced character of the pathological coronary condition and the development of collateral circulation but also by the sensitivity of the separate ECG leads and the presence and localization of cicatricial changes in the myocardium. 相似文献
203.
Edmundas Kibirkštis Asta Kabelkaitė Leszek Markowski Valdas Miliūnas 《Microscopy research and technique》2013,76(9):890-892
To determine whether the geometrical accuracy of small printed elements does not worsen on recycled paper, microscopic analysis of the dot area and the graphic elements raggedness printed on different types of recycled and coated papers at different screen ruling was carried out. Experimental tests have shown that geometrical accuracy of small elements printed on recycled paper/cardboard, in comparison to pictures printed on primary production paper is almost the same. Microsc. Res. Tech. 76:890–892, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
204.
H Tjalsma VP Kontinen Z Prágai H Wu R Meima G Venema S Bron M Sarvas JM van Dijl 《Canadian Metallurgical Quarterly》1999,274(3):1698-1707
Computer-assisted analyses indicate that Bacillus subtilis contains approximately 300 genes for exported proteins with an amino-terminal signal peptide. About 114 of these are lipoproteins, which are retained in the cytoplasmic membrane. We have investigated the importance of lipoprotein processing by signal peptidase II (SPase II) for cellular homeostasis, using cells lacking SPase II. The results show that lipoprotein processing is important for cell viability at low and high temperatures, suggesting that lipoproteins are essential for growth under these conditions. Although certain lipoproteins are required for the development of genetic competence, sporulation, and germination, these developmental processes were not affected in the absence of SPase II. Cells lacking SPase II accumulated lipid-modified precursor and mature-like forms of PrsA, a folding catalyst for secreted proteins. These forms of PrsA seem to have a reduced activity, as the secretion of alpha-amylase was strongly impaired. Unexpectedly, type I signal peptidases, which process secretory preproteins, were not involved in alternative amino-terminal processing of pre-PrsA in the absence of SPase II. In conclusion, processing of lipoproteins by SPase II in B. subtilis is not strictly required for lipoprotein function, which is surprising as lipoproteins and type II SPases seem to be conserved in all eubacteria. 相似文献
205.
Air drying characteristics and moisture diffusivity of carrots 总被引:1,自引:0,他引:1
Magdalena Zielinska Marek Markowski 《Chemical Engineering and Processing: Process Intensification》2010
The effects of air temperature on drying kinetics of carrot cubes were investigated. Convective drying characteristics of carrot cubes in a spout-fluidized bed were evaluated through the effect of air temperature on drying kinetics. Drying was carried out at 60, 70, 80 and 90 °C and the falling drying rate data were used to calculate the effective diffusion coefficients from the Fick's equation. Four mathematical models available in the literature were fitted to the experimental data. The Two-term model is given better prediction than the Henderson and Pabis, Page and Lewis model and satisfactorily described drying characteristics of carrot cubes. 相似文献
206.
Jarosław Markowski Monika Zbrzeźniak Monika Mieszczakowska-Frąc Krzysztof Rutkowski Wioletta Popińska 《LWT》2012,49(2):263-266
BackgroundPears due to low acidity are a suitable raw material for the production of multifruit nectars thus it is justified to determine the chemical composition and investigate the effect of cultivar and fruit maturity on juices quality.MethodsJuices from ‘Alexander Lucas’ and ‘Conference’ cultivars were produced after harvest and after 3 months of pears storage.ResultsAverage yield of clear juices was 76.4% for ‘Conference’ cultivar and 74.3% for ‘Alexander Lucas’. In the case of cloudy juices, the yield was lower by about 3%. Processing of ‘Conference’ cv. from stored fruit resulted in yield decrease compared to fruits after harvest; this was not in case of ‘Alexander Lucas’ in 2008, where juices produced from stored fruits were characterized by a higher yield compared to fresh fruit.Total solids content in clear juices was 125–135 g/L and 135–141 g/L for cloudy juices. ABTS●+ and total phenolics analysis showed that cloudy juices were characterized by a higher antioxidant activity and phenolics content than the clear ones.ConclusionPear storage, on the contrary to apples, does not decrease their suitability for cloudy juice production. Cloudy juices as a rule have higher antioxidant activity than the clear ones. 相似文献
207.
The experiment examined the anticipatory modulation of grip force with respect to load force during a drawer opening task. An impact force was introduced by a mechanical stop that arrested movement of the pulling hand. The results showed a typical grip force profile which consisted of two evolving phases, one to control drawer movement onset, and the other to secure grip force at the expected impact. Initially, grip force increased with the load force that was developed to overcome the inertia of the drawer. After the first peak, a small decline was observed, followed by a proactive grip force increase prior to the time of impact. During this ramp-like increase of grip force, load force remained unchanged. In addition, a reactive response was triggered by the impact. That anticipatory control with respect to an impact force is not innate but, rather, is learned by experience was evidenced by a comparison of adults and children. Whereas adults made the characteristic grip force adjustments to anticipate the impact, children used a probing strategy with irregular build-up of force until impact. Furthermore, adults calibrated the second phase of the grip force profile in the initial trials of the task, indicating that grip force was rapidly updated with information related to the impact force. The present results demonstrate that grip-load force coordination during manipulation is a necessity for dealing with destabilizing load perturbations produced by self-induced movement and impact forces. It is concluded that grip force is adjusted automatically, but in a flexible manner, to secure grip in accordance with the characteristics of the pulling synergy. 相似文献
208.
More than half out of 40 projects for the medical science development by the year of 2000 have been connected with the bio-active edible additives that are called "the food of XXI century", non-pharmacological means for many diseases. Most of these additives--nutricevtics and parapharmacevtics--are intended for the enrichment of food rations for the sick or healthy people. The ecologicaly safest and most effective are combined domestic adaptogens with immuno-modulating and antioxidating action that give anabolic and stimulating effect,--"leveton", "phytoton" and "adapton". The MKTs-229 tablets are residue discharge means. For atherosclerosis and general adiposis they recommend "tsar tablets" and "aiconol (ikhtien)"--on the base of cod-liver oil or "splat" made out of seaweed (algae). All these preparations have been clinically tested and received hygiene certificates from the Institute of Dietology of the Russian Academy of Medical Science. 相似文献
209.
VP Zuev PV Sergeev AS Pankratov EN Bolotova AV Seme?kin NL Shimanovski? 《Canadian Metallurgical Quarterly》1994,73(2):5-7
Ceramic hydroxyapatite is frequently used in clinical practice nowadays; it is applied in surgical interventions on facial skull bones. This biological material is used as bone substitute and bone connector, but many authors claim that it is devoid of osteoinductor properties. Research is in progress on the effects of a "cold", that is, biochemically active form of ceramic hydroxyapatite on proliferative activity of a number of cell populations. No mitogenesis stimulation was observed during incubation of hydroxyapatite with osteoblast culture; on the contrary, a reduction of proliferative processes intensity was observed. Remembering that hydroxyapatite is a surfactant we repeated this experiment under similar conditions but used a hydroxyapatite molbfication with specific activity increased by two orders in comparison with its close analogs. Mitogenesis intensity was assessed by radiometric method from 3H-thymidine incorporation. The data indicated stimulation of proliferative processes in osteoblast culture. 相似文献