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51.
PJ Borron EC Crouch JF Lewis JR Wright F Possmayer LJ Fraher 《Canadian Metallurgical Quarterly》1998,161(9):4599-4603
Components of the airspace-lining material may contribute to the local regulation of immune function within the lung. We report here that recombinant rat pulmonary surfactant-associated protein D (SP-D) inhibits the lectin- and anti-CD3-stimulated proliferation of human PBMCs. Inhibition was associated with a decreased production of IL-2, and the addition of human rIL-2 blocked the inhibitory action of SP-D. These effects were not inhibited by maltose, indicating that the inhibitory activity was not dependent upon the lectin activity of SP-D. Studies employing mutant SP-D lacking N-linked sugars or defective in multimerization further indicated that inhibition was not dependent upon cellular interactions with the N-linked oligosaccharide on SP-D or the oligomerization of trimeric SP-D subunits. Although a peptide containing an inverted DGR showed similar IL-2-dependent effects on anti-CD3-stimulated proliferation, deletion of the conserved DGRDGR sequence near the amino-terminal end of the collagen domain did not decrease the suppressive activity of SP-D. We hypothesize that SP-D can dampen lymphocyte responses to exogenous stimuli and protect the lung against collateral immune-mediated damage. 相似文献
52.
S Wissink EC van Heerde B vand der Burg PT van der Saag 《Canadian Metallurgical Quarterly》1998,12(3):355-363
The mutants of Saccharomyces cerevisiae assigned to complementation group G199 are deficient in mitochondrial respiration and lack a functional cytochrome oxidase complex. Recombinant plasmids capable of restoring respiration were cloned by transformation of mutants of this group with a yeast genomic library. Sequencing indicated that a 2.1-kb subclone encompasses the very end (last 11 amino acids) of the PET111 gene, the COX7 gene and a new gene (YMR255W) of unknown function that potentially codes for a polypeptide of 188 amino acids (about 21.5 kDa) without significant homology to any known protein. We have shown that the respiratory defect corresponding to group G199 is complemented by plasmids carrying only the COX7 gene. The gene YMR255W was inactivated by one-step gene replacement and the disrupted strain was viable and unaffected in its ability to grow in a variety of different test media such as minimal or complete media using eight distinct carbon sources at three pH values and temperatures. Inactivation of this gene also did not affect mating or sporulation. 相似文献
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A retrospective study of 105 barium follow-through examinations on 102 patients suspected of having malabsorption syndrome has been carried out to assess the usefulness of this technique in the diagnosis of coeliac disease. Comparison with histological and biochemical data has been made. Of the 34 examinations on 31 patients with a proven diagnosis of coeliac disease, 30 examinations showed both abnormal X-ray and biopsy findings, two examinations showed normal X-ray appearance but abnormal jejunal biopsy and two showed normal jejunal histology but abnormal X-ray findings. There were two cases with sensitivity, non-invasive nature, ease and cheapness of the technique, barium follow-through examination is suggested as the initial investigation in patients suspected of coeliac disease. 相似文献
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An innovative model for organising social services in a community, the Imbrication Model, is contrasted with two traditional models, the Entrepreneurial and the Umbrella Agency. The structural characteristics and dynamics of the three models are illustrated with actual case histories. Imbrication Model calls for the interlocking of personnel from several agencies, with the purpose of redirecting the dysfunctional interagency rivalry prevalent in the traditional models. Imbrications at all organisational levels--Board of Directors, Administrators and Staff--facilitate adoption of the superordinate goal of providing clients with the best services available, regardless of which particular agency delivers the service. Few observers of the current social service scene would challenge the statement that needs for service are unlimited and resources limited. In the USA the imbalance between needs and resources persists despite a decade of massive governmental programmes intended to alleviate social ills. Recent substantial cutbacks in federal funds, moreover are not likely to improve the situation. The resource shortage involves more than a limitation of funds. Deliverers of service and competent programme administrators are also on critically short supply. These shortages are more often than not exacerbated by a chronic spirit of competition among agencies and programmes at the local level. Three organizational models for the delivery and administration of social services, two conventional and one of more recent date, are examined in this article. The innovative model, which has been named the Imbrication Model, explicitly calls for redirecting interagency rivalry and competition. Its ambitious goal is to integrate the efforts of those attempting to meet a community's social service needs. 相似文献
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Very low birth weight children at school age: comparison of neonatal management methods 总被引:1,自引:0,他引:1
ES Steiner EM Sanders EC Phillips CR Maddock 《Canadian Metallurgical Quarterly》1980,281(6250):1237-1240
The outcome of 293 infants born to a geographically defined community and weighing 501-1500 g was investigated. Medical intervention in the newborn period had been avoided. Morbidity was assessed at school age. Of the infants, 236 had been live born in the labour ward of this hospital; of these, 117 (49.6%) died in the neonatal period, one (0.4%) died in the first year, four (1.7%) were untraced, 13 (5.5%) had major handicap, 29 (12.3%) had minor handicap, and 72 (30.5%) were considered to be normal. In terms of survival, handicap, and intellectual with that of infants born over the same period (1963-71) in areas where intensive methods of perinatal care were used. These results imply that postnatal survival and potential of infants of very low birth weight are by no means prejudiced when only experienced nursing care is available. 相似文献
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Antennally active, bark-derived, angiosperm volatiles were tested singly and in groups for their ability to disrupt the response of the Douglas-fir beetle (DFB), Dendroctonus pseudotsugae, to attractant-baited multiple-funnel traps. One compound, conophthorin, was active alone in reducing the response of beetles to the baited traps. Further experiments showed disruptive activity in two aliphatic green-leaf alcohols [1-hexanol and (Z)-3-hexen-1-ol], as well as guaiacol and benzyl alcohol, and three aliphatic aldehydes [nonanal, hexanal, and (E)-2-hexenal] but not in two aromatic aldehydes (benzaldehyde and salicylaldehyde). Every binary combination that included conophthorin or any two of the other groups, except aromatic aldehydes, significantly reduced the response of beetles to baited traps. Various ternary mixtures and the complete mixture of all the groups were generally the most effective treatments. These results provide evidence that DFBs recognize and avoid nonhosts while flying rather than landing on candidate hosts and testing them while in contact with the tree. Nonhost angiosperm bark volatiles may have practical utility on their own or in combination with the antiaggregation pheromone 3-methylcyclohex-3-en-1-one (MCH) to protect single trees, logs, or stands from attack by the DFB. 相似文献