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61.
Sixty-five coronary patients were subjected to aortocoronary bypass surgery. Three groups were distinguished: 1) controls-no filters; 2) patients in whom hemotransfusion (40 mu) and infusion filters were used during and on day 1 after surgery; and 3) in whom leukocyte filters for filtering residual perfusate from artificial circulation device were used in addition to the filters used in group 2. In the controls plasma level of leukocytic alpha-glycoprotein after artificial circulation increased 22 to 36 times, whereas in groups 2 and 3 it did not increase at all. After surgery the severity of leukocytosis, hyperthermia, and hyperenzymia assessed from the level of SGOT was reliably lower in patients in whom the filters were used. The time course of the oxygenation index (PaO2/FiO2) indicated an improvement of gas exchange due to filtration of infusion-transfusion media. The minimal values of PaO2/FiO2) and plasma content of C-reactive protein were observed in group 3. The mechanisms of systemic inflammatory reaction and organ dysfunction and some aspects of the protective effect of filters are discussed. 相似文献
62.
Coplanar waveguide (CPW) and thin film microstrip (TFMS) lines integrating porous ultra low-k as inter-metal dielectric layers (k = 2.5) and copper as metal, are for the first time experimentally measured up to 110 GHz and under different temperature conditions, up to 200 °C. The extracted attenuation and propagation coefficients of those transmission lines are compared to simulations performed with MAGWEL software, a frequency domain 3-D Maxwell solver. Based on the characterization results some guidelines related to interconnect design are presented for future applications. 相似文献
63.
LG Yu DG Fernig MR White DG Spiller P Appleton RC Evans I Grierson JA Smith H Davies OV Gerasimenko OH Petersen JD Milton JM Rhodes 《Canadian Metallurgical Quarterly》1999,274(8):4890-4899
The Galbeta1-3GalNAcalpha (TF antigen)-binding lectin (ABL) from the common edible mushroom (Agaricus bisporus) has a potent anti-proliferative effect without any apparent cytotoxicity. This unusual combination of properties prompted investigation of its mechanism of action. In contrast to soluble lectin, agarose-immobilized, and hence noninternalizable ABL had no effect on proliferation of HT29 colon cancer cells. Electron microscopy of HT29 cells incubated with fluorescein- and gold-conjugated ABL showed internalization of the lectin into endocytotic vesicles and multivesicular bodies. Confocal microscopy showed perinuclear accumulation of fluorescein isothiocyanate-conjugated lectin, which also inhibits HT29 cell proliferation, raising the possibility that the lectin might interfere with nuclear pore function. Transport of heat shock protein 70 into the nucleus in response to heat shock was blocked by preincubation of HT29 cells for 6 h with 40 micrograms/ml ABL. In digitonin-permeabilized cells, nuclear uptake of bovine albumin conjugated to a nuclear localization sequence (NLS)-containing peptide was also inhibited by a 15-min preincubation with 40-100 micrograms/ml ABL. In contrast, serum-stimulated nuclear translocation of mitogen-activated protein kinase, which is NLS-independent, was not affected by pretreatment of cells with the lectin. These results suggest that the anti-proliferative effect of ABL is likely to be a consequence of the lectin trafficking to the nuclear periphery, where it blocks NLS-dependent protein uptake into the nucleus. 相似文献
64.
MD Mowery RS Hutchins P Molina M Alajarín A Vidal LG Bachas 《Canadian Metallurgical Quarterly》1999,71(1):201-204
An SO2 gas sensor was developed by using a hydrogen sulfite-selective electrode positioned behind a gas-permeable membrane (GPM). The hydrogen sulfite-selective electrode was prepared by incorporating a multicyclic guanidinium ionophore in a plasticized poly(vinyl chloride) membrane. This gas sensor presents important advantages over the conventional Severinghaus-type SO2 gas sensor that contains a pH electrode immersed in an internal solution behind the GPM. The Severinghaus gas sensor suffers interferences from weak acids that can cross the GPM as gases and change the pH of the internal solution. In contrast, in the proposed sensor, the excellent selectivity of the HSO3- electrode and the ability of the GPM to discriminate gaseous from nongaseous species combine to generate the most selective potentiometric SO2 gas sensor reported to date. 相似文献
65.
Leena Maunula Agnieszka Kaupke Petra Vasickova Kirsi Söderberg Iwona Kozyra Sava Lazic Wim H.M. van der Poel Martijn Bouwknegt Saskia Rutjes Kris A. Willems Rita Moloney Martin D'Agostino Ana Maria de Roda Husman Carl-Henrik von Bonsdorff Artur Rzeżutka Ivo Pavlik Tamas Petrovic Nigel Cook 《International journal of food microbiology》2013
In recent years, numerous foodborne outbreaks due to consumption of berry fruit contaminated by human enteric viruses have been reported. This European multinational study investigated possible contamination routes by monitoring the entire food chain for a panel of human and animal enteric viruses. 相似文献
66.
NN Ninkina EM Privalova LG Pin?n AM Davies VL Buchman 《Canadian Metallurgical Quarterly》1999,246(2):308-311
Synucleins constitute a group of unique, evolutionarily conserved proteins that are expressed predominantly in neurons of the central and peripheral nervous system. Although the normal cellular functions of synucleins are not clear, these proteins have been implicated in various neurodegenerative conditions in humans. We found that persyn, a recently characterized member of the synuclein family, is expressed not only in the nervous system but also in the stratum granulosum of the epidermis of neonatal and adult mice. This finding together with our recent observations that persyn influences neurofilament network integrity in sensory neurons raises the possibility that persyn in skin could be involved in modulation of the keratin network. 相似文献
67.
The Single Flying Capacitor Converter (SFCC) and Dual Flying Capacitor Converter (DFCC) are two-quadrant power supplies for energy storage and transfer systems. They have applications in nuclear research and pulsed power systems in which superconductive coils are used. In this paper analytical expressions for the time-averaged behaviours of SFCC and DFCC are derived by using averaging technique. Because large superconductive magnet coils are used, time constants of the switched circuits are large enough compared to the switching period. Therefore, an averaged PWM switch equivalent circuit is substituted into the original converter circuits to find the averaged system equations. With this new insight in the averaged dynamics, their design and control can be optimized. Although DFCC has less coil current ripple compared to SFCC, the analysis will show that the averaged behaviours of both converters are the same. 相似文献
68.
69.
The N-terminal region of human cystatin C has been shown to be of crucial importance for the interaction of the inhibitor with cysteine proteinases. However, several studies have been unable to identify the corresponding region in bovine cystatin C, indicating that the binding of proteinases to the bovine inhibitor may not be dependent on this region. With the aim to resolve this apparent discrepancy and to elucidate the relation of bovine cystatin C to other cystatins, we have isolated a cDNA clone encoding bovine precystatin C. The sequence of this cDNA was similar to that of the human inhibitor and showed a putative signal peptidase cleavage site consistent with the N-terminal regions of the bovine and human inhibitors being of comparable size. This suggestion was verified by determination of the relative molecular mass of the mature bovine inhibitor isolated from cerebrospinal fluid under conditions minimising proteolysis. The N-terminal of the purified inhibitor was blocked, but the sequence of the N-terminal peptide produced by digestion with endopeptidase LysC could be unequivocally determined by tandem mass spectroscopy. Together, these results show that bovine cystatin C has 118 residues, in contrast with 110-112 residues reported previously, and has an N-terminal region analogous to that of human cystatin C. This region presumably is of similar importance for tight binding of target proteinases as in the human inhibitor. 相似文献
70.
D Chau JS Mancoll S Lee J Zhao LG Phillips GK Gittes MT Longaker 《Canadian Metallurgical Quarterly》1998,40(5):490-493
BACKGROUND: It has recently been suggested that primary lactase deficiency might have been selected for by malaria, as occurred for beta-thalassaemia and glucose 6-phosphate dehydrogenase deficiency. However, recently we have found that the prevalence of primary lactase deficiency in the area of Sassari (Northern Sardinia), where, in the past, there was intermediate malarial endemicity, is comparable to that observed in the adult population from other areas of Southern Italy where malaria was less endemic. AIMS: To address the problem further, we have determined the prevalence of primary lactase deficiency, glucose 6-phosphate dehydrogenase deficiency deficiency and beta-thalassaemia trait in the populations of three Sardinian villages which differ in altitude above sea-level, socioeconomic features, history of endemic malaria and prevalence of b-thalassaemia and glucose 6-phosphate dehydrogenase deficiency. SUBJECTS: We tested 138 adult males: 53 were from Fonni (a non-malarial mountain village, with a strong pastoral tradition), 38 from Lodé (a village with a similar pastoral tradition, but high malarial endemicity in the past) and 47 from Terralba (a lowland fishing village with an agricultural tradition and heavy malarial morbidity and mortality). METHODS: A blood sample was obtained in all subjects for determination of HbA2 and glucose 6-phosphate dehydrogenase activity. Lactase deficiency was assessed by measuring breath hydrogen production after oral administration of lactose (50 g), by gas-chromatography. RESULTS: The frequencies of glucose 6-phosphate dehydrogenase deficiency and of beta-thalassaemia trait in the non-malarial village of Fonni were strikingly low, compared to frequencies found in the two villages (Terralba and Lodé) with a very high past malarial morbidity. In contrast, there was no significant difference in the prevalence of lactase deficiency in the three groups of subjects from the three villages. CONCLUSIONS: These data obtained in Northern Sardinia do not support the hypothesis of a selection of primary lactase deficiency by malaria. For definitive conclusions, however, the malaria hypothesis should be tested in other parts of the world. 相似文献