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61.
62.
Granulomas and cholestatic--hepatocellular injury associated with phenylbutazone. Report of two cases 总被引:1,自引:0,他引:1
A combined cholestatic-hepatocellular injury and noncaseating granulomas occurred in two patients 1 and 4 weeks after phenylbutazone therapy. Both patients were jaundiced, one had a macular rash, and both had peripheral blood eosinophilia. Symptoms and signs subsided, and abnormal findings from tests of hepatic function rapidly returned to normal following withdrawal of the drug. Sections of liver biopsy specimens 6 months later showed no granulomas or other pathologic changes. Previously reported cases are reviewed. 相似文献
63.
Using 376 airmen, Whitlock and Cureton (see 35: 7252) collected attitude score and biographical data, which is reanalysed in the present study, using multiple regression techniques. "… much of the criterion variance associated with attitude measures is also related to more easily obtained biographical characteristics of workers and biographical variables should be considered when relating attitudes to productivity." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
The tools we use at the human scale, whether mechanical, medical or microelectronic, depend on materials for which some other scale of length or time is critical. Often this is the mesoscale, between the scales of engineering and of atomic science. Linking underlying processes to what we handle is sometimes called 'spanning' (or 'bridging') length scales, giving the impression that the mesoscale is a swamp to be crossed without getting mud on our boots. This is misleading: we do not wish to span the mesoscale, but to work at the appropriate scale, and to connect that to our human needs. The appropriate scale need not rule out multiscale computer modelling, in which some supercode integrates relevant scales in one pass, hoping to combine the best of methods for two or more levels. But the reality for such attempts, too often, is that the worst of both regimes are found. Happily, simpler strategies at a judicious scale will often suffice. 相似文献
65.
Understanding user needs for geographic information and the factors which influence the usability of such information in diverse user contexts is an essential part of user centred development of information products. There is relatively little existing research focused on the design and usability of information products in general. This paper presents a research approach based on semi structured interviews with people working with geographic information on a day to day basis, to establish a reference base of qualitative data on user needs for geographic information with respect to context of use. From this reference data nine key categories of geographic information usability are identified and discussed in the context of limited existing research concerned with geographic information usability. 相似文献
66.
Salicylate-containing phenolic glycosides (PGs) are abundant and often play a dominant role in plant-herbivore interactions
of Populus and Salix species (family Salicaceae), but the biosynthetic pathway to PGs remains unclear. Cinnamic acid (CA) is thought to be a precursor
of the salicyl moiety of PGs. However, the origin of the 6-hydroxy-2-cyclohexen-on-oyl (HCH) moiety found in certain PGs,
such as salicortin, is not known. HCH is of interest because it confers toxicity and antifeedant properties against herbivores.
We incubated Populus nigra leaf tissue with stable isotope-labeled CA, benzoates, and salicylates, and measured isotopic incorporation levels into both
salicin, the simplest PG, and salicortin. Labeling of salicortin from [13C6]-CA provided the first evidence that HCH, like the salicyl moiety, is a phenylpropanoid derivative. Benzoic acid and benzaldehyde
also labeled both salicyl and HCH, while benzyl alcohol labeled only the salicyl moiety in salicortin. Co-administration of
unlabeled benzoates with [13C6]-CA confirmed their contribution to the biosynthesis of the salicyl but not the HCH moiety of salicortin. These data suggest
that benzoate interconversions may modulate partitioning of phenylpropanoids to salicyl and HCH moieties, and hence toxicity
of PGs. Surprisingly, labeled salicyl alcohol and salicylaldehyde were readily converted to salicin, but did not result in
labeled salicortin. Co-administration of unlabeled salicylates with labeled CA suggested that salicyl alcohol and salicylaldehyde
may have inhibited salicortin biosynthesis. A revised metabolic grid model of PG biosynthesis in Populus is proposed, providing a guide for functional genomic analysis of the PG biosynthetic pathway. 相似文献
67.
68.
AM Hodge RA Westerman MP de Courten GR Collier PZ Zimmet KG Alberti 《Canadian Metallurgical Quarterly》1997,21(1):50-53
We performed a case-control study to investigate the association of the poor metaboliser genotype of the cytochrome P450 2D6 gene with Parkinson's disease (PD). Genotyping was determined by the polymerase chain reaction followed by digestion with restriction enzymes. The poor metaboliser genotype was more frequent in 112 patients with PD than in 206 matched controls (odds ratio 1.7, 95% CI: 0.94-2.45). A meta-analysis of these results together with ten other published studies gave a pooled odds ratio for the poor metaboliser genotype of 1.47 (95% CI: 1.18-1.96, P=0.01). Thus, the poor metaboliser genotype has a small but highly significant association with PD which would be easily missed in small studies. Research now should focus on the mechanism of this association. 相似文献
69.
S Ashraf Y Tian D Cowan A Entress PG Martin KG Watterson 《Canadian Metallurgical Quarterly》1997,64(6):1790-1794
BACKGROUND: Heparin bonding of the cardiopulmonary bypass (CPB) circuit may be associated with a reduced inflammatory response and improved clinical outcome. The relative contribution of a heparin-bonded oxygenator (ie, >80% of circuit surface area) to these effects was assessed in a group of pediatric patients. METHODS: Twenty-one pediatric patients undergoing CPB operations were assigned randomly to receive either a heparin-bonded oxygenator (group H, n = 11) or a nonbonded oxygenator (group C, n = 10) in otherwise nonbonded circuits. The two groups were similar in pathology, age, weight, CPB time, and cross-clamp time. Plasma levels of the cytokines tumor necrosis factor-alpha, interleukin-6, and interleukin-8, as well as terminal complement complex, neutrophils, and elastase, were analyzed before, during, and after CPB. RESULTS: Significant levels of tumor necrosis factor-alpha were not detected in either group. Plasma levels of all other markers increased during and after CPB compared with baseline. Plasma levels of interleukin-6 peaked in both groups 2 hours after the administration of protamine but remained significantly higher in group C 24 hours after operation. Plasma concentrations of interleukin-8 peaked at similar levels in both groups 30 minutes after protamine administration and returned to baseline thereafter. Levels of terminal complement complex and elastase peaked in both groups 30 minutes after protamine administration. Plasma levels of terminal complement complex were significantly higher at the end of CPB and after protamine administration in group C. Elastase levels were significantly higher 2 and 24 hours after CPB in group C. The ventilation time of patients in group H was significantly lower than that of patients in group C: 10 (range, 3 to 24) versus 22 (range, 7 to 24) hours, respectively (p < 0.01). CONCLUSIONS: The present study confirms the proinflammatory nature of pediatric operations and demonstrates a lessened systemic inflammatory response with the use of heparin-bonded oxygenators. This is achieved without bonding of the entire circuit, which could have significant cost-benefit implications by negating the need for custom-built heparin-bonded circuitry. 相似文献
70.