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11.
SD Shiian SV Kha?dukov AL Pukhal''ski? AP Toptygina NV Bovin 《Canadian Metallurgical Quarterly》1996,41(2):24-29
The interaction of human peripheral blood leukocytes with alpha 1-acid glycoprotein (AGP), its glycoforms as well as neoglyco-conjugates representing carbohydrate chains of AGP or its fragments was studied by flow cytometry. It was shown that the main target cells for AGP as well as for conjugates of its carbohydrate chains with polyacrylamide (PAA) are monocytes and polymorphonuclear leukocytes but not lymphocytes. The interaction of AGP with monocytes and granulocytes are mediated by its carbohydrate chains: the binding of AGP with cells was inhibited by AGP, AGP oligosaccharides as well as conjugates of oligosaccharides and its fragments with PAA. The data obtained show the existence of monocyte (and granulocyte) receptors which interact with complex type sialooligosaccharides of AGP. 相似文献
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This article examines the determinants of first-time use durations of the injectable contraceptive Depo Medroxy Progesterone Acetate (DMPA) for rural Bangladeshi women. The method's side effects were defined by 200 first-time users in Matlab district during lengthy, open-ended interviews. Women with many children used the method longer than did women of low parity. Those who experienced side effects had shorter use durations than those who did not, and those who cited heavy bleeding as their main problem discontinued use soonest. Women whose husbands approved of family planning had significantly longer use durations than those whose husbands disapproved. Respondents who adopted DMPA because of perceived positive aspects of the drug used it longer than those who chose it for other reasons. Results of the study underscore the importance of viewing side effects in a specific social and cultural context. Expanded side-effects counseling for women and their husbands is needed. 相似文献
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Experimental results are presented to show that the adhesion force is the single most important limiting factor in high-resolution atomic force microscopy of DNA in air, prepared by the cytochrome-C-assisted spreading method. It is also shown that humidity plays a minor role in the control of probe force. Using a pure carbon film as the substrate to clean the AFM tip prior to imaging, it is demonstrated that 4-6 nm resolution on DNA can be routinely obtained by the atomic force microscope with commercial Si3N4 pyramid cantilevers. We also show that in organic solvents a resolution of up to 3 nm can be obtained under optimal conditions. 相似文献
14.
AP Christiansen B Wanscher HB Larsson O Henriksen 《Canadian Metallurgical Quarterly》1994,156(43):6348-6352
Multiple sclerosis is a chronic demyelinating disease. Paraclinical examinations may contribute to the diagnosis of multiple sclerosis. Magnetic resonance imaging (MRI) has a very high sensitivity concerning multiple sclerosis, and has made it possible to visualize multiple sclerosis plaques in vivo, to follow each plaque over the course of time and in this way to obtain information about the pathogenesis. MRI has shown that the size of plaques may vary considerably, and that plaques are dynamic structures with the ability to change in size over few weeks. By using MRI and the contrast agent Gadolinium-DTPA, it is possible to distinguish a newly developed plaque from an older one. Therefore, MRI has become an important examination in therapeutic trials. Just now, MRI with Gadolinium-DTPA is being used to evaluate the efficacy of plasmapheresis and immunoglobulin treatment in a joint study between Rigshospitalet and Hvidovre Hospital. 相似文献
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Deterioration of concrete or reinforcing steel through excessive contaminant concentration is often the result of repeated
wetting and drying cycles. At each cycle, the absorption of water carries new contaminants into the unsaturated concrete.
Nuclear Magnetic Resonance (NMR) is used with large concrete samples to observe the shape of the wetting profile during a
simple one-dimensional wetting process. The absorption of water by dry concrete is modelled by a nonlinear diffusion equation
with the unsaturated hydraulic diffusivity being a strongly nonlinear function of the moisture content. Exponential and power
functions are used for the hydraulic diffusivity and corresponding solutions of the diffusion equation adequately predict
the shape of the experimental wetting profile.
The shape parameters, describing the wetting profile, vary little between different blends and are relatively insensitive
to subsequent re-wetting experiments allowing universal parameters to be suggested for these concretes.
Résumé La détérioration du béton ou du béton armé à travers la concentration excessive de contaminant est souvent le résultat de cycles humides et secs répétés. A chaque cycle, l'absorption de l'eau amène de nouveaux contaminants à l'intérieur du béton non saturé en eau. Pour observer le profil du processus d'humidification, on peut utiliser la Résonance Magnétique Nucléaire (RMN) sur de grands échantillons de béton dans le cadre d'une simple étude unidimensionnelle de ce profil. Il est démontré que l'absorption d'eau par du béton sec peut être précisément modélisée par une équation de diffusion non linéaire où la diffusivité hydraulique non saturée est fonction hautement non linéaire de l'humidité du contenant. Des fonctions exponentielles et puissances peuvent définir la diffusivité hydraulique. Les solutions résultant de l'équation modélisant cette diffusion permettent de prédire avec précision la forme du profil de l'humidification expérimentale. Les paramètres de forme qui décrivent le profil de l'humidification varient peu entre les différents mélanges de béton et sont relativement insensibles à des expériences de réhumidification ultérieures. Cela permet de suggérer que ces bétons suivent des paramètres d'humidification universels.相似文献
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FV Elmslie AJ Vivian H Gardiner C Hall AP Mowat RM Winter 《Canadian Metallurgical Quarterly》1995,32(4):264-268
Alagille syndrome (AGS) is one of the major forms of chronic liver disease in childhood with severe morbidity and a mortality of 10 to 20%. It is characterised by cholestasis of variable severity with paucity of interlobular bile ducts and anomalies of the cardiovascular system, skeleton, eyes, and face. Previous studies suggest a wide variation in the expression of the disease and a high incidence of new mutations. To determine more accurately the rate of new mutations and to develop criteria for detecting the disorder in parents we systematically investigated parents in 14 families with an affected child. Clinical examination was supplemented by liver function tests, echocardiography, radiographic examination of the spine and forearm, ophthalmological assessment, and chromosome analysis. Six parents had typical anomalies in two or more systems pointing to the presence of autosomal dominant inheritance. Systematic screening of parents for the features defined in this study should improve the accuracy of genetic counselling. 相似文献
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