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排序方式: 共有1697条查询结果,搜索用时 960 毫秒
91.
MK Hong SW Park CW Lee DH Kang JK Song JJ Kim SJ Park MK Hong GS Mintz MB Leon 《Canadian Metallurgical Quarterly》1998,82(5):670-3, A8
We evaluated the role of intravascular ultrasound (IVUS) in 16 patients with unprotected left main coronary artery (LMCA) stenting compared with 80 patients with other (non-LMCA) native coronary artery stenting and found that (1) additional high-pressure or larger size balloon dilations were more frequently performed in LMCA stenting than in non-LMCA stenting (p <0.05) and (2) after IVUS-guided stent implantation, minimum lumen area was > or = 9 mm2 in 88% of patients who underwent LMCA stenting and in 19% of those who underwent non-LMCA stenting (p <0.001). IVUS guidance may be a more important adjunctive imaging modality in the stenting of unprotected LMCA stenoses than in stenting of non-LMCA stenoses. 相似文献
92.
We report the findings of a cross-sectional epidemiologic study of Giardia lamblia and Cryptosporidum infections in Jamaica. Three hundred twenty eight stool samples from patients less than one to 81 years of age were examined using formalin-ether concentration for G. lamblia, Zeihl-Neelsen staining for Cryptosporidium, and the Prospect rapid enzyme immunoassay (EIA; Alexon, Sunnyvale, CA) for parasite diagnosis. The Prospect Giardia rapid assay detected 17 cases of G. lamblia infection compared with six by formalin-ether concentration. However, the Prospect Cryptosporidum EIA did not increase the rate of detection of Cryptosporidum when compared with Zeihl-Neelsen staining. Cryptosporidum infections were most frequently diagnosed in children less than five years old and prevalence decreased with age. In contrast, the prevalence of giardiasis increased as children became older. There were no associations between the infections and stool consistency, clinical manifestations, or sex of the individuals. The contribution of the parasites to childhood morbidity will depend on accurate laboratory diagnosis. 相似文献
93.
The dominant Chinese hamster ovary cell glycosylation mutant, LEC18, was selected for resistance to pea lectin (Pisum sativum agglutinin (PSA)). Lectin binding studies show that LEC18 cells express altered cell surface carbohydrates with markedly reduced binding to 125I-PSA and increased binding to 125I-labeled Datura stramonium agglutinin (DSA) compared with parental cells. Desialylated [3H]Glc-labeled LEC18 cellular glycopeptides that did not bind to concanavalin A-Sepharose exhibited an increased proportion of species that were bound to DSA-agarose. Most of these glycopeptides bound to ricin-agarose and were unique to LEC18 cells. This fraction was purified from approximately 10(10) cells and shown by 1H NMR spectroscopy and methylation linkage analysis to contain novel N-linked structures. Digestion of these glycopeptides with mixtures of beta-D-galactosidases and N-acetyl-beta-D-glucosaminidases gave core glycopeptides that, in contrast to cores from parental cells, were mainly not bound to concanavalin A-Sepharose or to PSA-agarose. 1H NMR spectroscopy, matrix-assisted laser desorption ionization/time of flight mass spectrometry, electrospray mass spectrometry, and collision-activated dissociation mass spectrometry showed that the LEC18 core glycopeptides contained a new GlcNAc residue that substitutes the core GlcNAc residues. Methylation linkage analysis of the parent compound provided evidence that the GlcNAc is linked at O-6 to give the following novel, N-linked core structure. [formula: see text] 相似文献
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The Pi typing methods acid starch-gel electrophoresis (ASGE) and isoelectric focusing (IEF) have been compared by three reference laboratories: 564 samples of phenotypes Pi M, MS and MZ were tested in each of the three laboratories with a 96% agreement on initial typing. The discrepancies are recorded and reasons for disagreement discussed. IEF is a reliable method for Pi typing and gives results comparable to those obtained by ASGE. 相似文献
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98.
Effect of lipopolysaccharide on indices of peripheral and hepatic metabolism in lactating cows 总被引:2,自引:0,他引:2
Four multiparous lactating cows (175 to 220 d in milk [DIM]) were used in a 4 x 4 Latin square design to assess the effects of four doses (0.0, 0.5, 1.0, and 1.5 microg/kg of body weight) of lipopolysaccharide (LPS; Escherichia coli 0111:B4) on performance and plasma metabolite and hormone concentrations. In addition, effects of immune activation on in vitro hepatic metabolic capacity were evaluated in 12 multiparous lactating cows (150 to 220 DIM) infused with 0 (n = 6), 1.0 (n = 4) or 2.0 (n = 2) microg of LPS/kg. Milk production and DMI decreased linearly with LPS dose for 24 h after LPS infusion. Overall mean plasma tumor necrosis factor-alpha, insulin, glucagon, and cortisol concentrations increased linearly with LPS dose, and plasma beta-hydroxybutyrate decreased linearly by dose after LPS infusion. Infusion of LPS decreased the insulin:glucagon molar ratio, but did not affect plasma concentrations of growth hormone, insulin-like growth factor-1, leptin, or L-(+)-lactate. Plasma concentrations of glucose tended to increase initially and subsequently decrease, and there was a quadratic tendency for increased plasma nonesterified fatty acid concentrations after LPS administration. In vitro hepatic capacity for conversion of [1-(14)C]L-(+)-lactate and [1-(14)C]palmitate, but not [1-(14)C]propionate or [1-(14)C]L-alanine, to CO2 increased after LPS administration. Hepatic capacity to convert [1-(14)C]propionate to glucose tended to increase, but neither esterification nor the conversion of palmitate to acid soluble products was altered by LPS. The LPS infusion resulted in significant changes of endocrine mediators responsible for regulation of energy metabolism of lactating cows and tended to alter subsequent in vitro hepatic metabolic capacity. 相似文献
99.
Mechanical properties of lettuce 总被引:4,自引:0,他引:4
G. A. Toole M. L. Parker A. C. Smith K. W. Waldron 《Journal of Materials Science》2000,35(14):3553-3559
The fracture properties of Spanish Iceberg and English Round lettuce tissues were investigated using a tensile test on notched specimens. The level of notch sensitivity was investigated for samples of differing colour and vein orientation. Vein orientation perpendicular to the test direction proved to be the most notch sensitive and samples with vein orientation parallel to the test direction proved to be very notch insensitive, samples with a diagonal (45°) orientation showed an intermediate response. This response was interpreted in terms of the interaction of veins with the crack path. The strengths of English Round tissues were broadly comparable with those of Spanish Iceberg although the upper limits depended on vein orientation and were in the order: parallel > diagonal perpendicular. A similar ranking of vein orientation was found in estimates of stiffness. 相似文献
100.
Alexander James F.; Waldron Holly B.; Barton Cole; Mas C. Haydee 《Canadian Metallurgical Quarterly》1989,57(1):19
Parents' data were evaluated in three studies of families with a delinquent adolescent. Families were provided with different forms of a positive versus negative interactional (attributional) context. Study 1 demonstrated that the negative context elicited significantly more negative behaviors than did the positive context when parents interacted with each other and with their delinquent adolescent. Study 2 demonstrated that the dispositional attributions of parents were influenced by the manipulation of set, with a dissatisfied set producing negative blaming attributions and a satisfied set producing nonblaming, positive attributions. Study 3 demonstrated that parents' negative sets regarding their adolescent's negative behaviors, once established and discussed by the family for 5 min, were unresponsive to a subsequent positive reattribution regarding those behaviors. Taken together, the data provide some support for reattribution techniques such as relabeling. Yet, the data question the ease with which such techniques can be successful and challenge proponents of such techniques to develop methodologically sound empirical demonstrations of their effectiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献