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91.
Effect of the 5-lipoxygenase inhibitor ZD2138 on allergen-induced early and late asthmatic responses. 总被引:5,自引:3,他引:2
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S M Nasser G S Bell R J Hawksworth K E Spruce R MacMillan A J Williams T H Lee J P Arm 《Thorax》1994,49(8):743-748
BACKGROUND--Leukotrienes are lipid mediators generated from arachidonic acid by the 5-lipoxygenase pathway which may play an important part in the pathophysiology of asthma. Previous studies have demonstrated attenuation of the allergen-induced early and late asthmatic responses by leukotriene receptor antagonists. The effect of the 5-lipoxygenase inhibitor ZD2138, a non-redox lipoxygenase inhibitor which inhibits leukotriene synthesis for 24 hours after single doses of 350 mg, on allergen-induced early and late asthmatic responses has been assessed. METHODS--Eight asthmatic subjects with baseline FEV1 > 70% were studied. On screening, all subjects developed an allergen-induced biphasic asthmatic response to grass pollen, cat dander, or house dust mite. ZD2138 (350 mg) or placebo was given on two occasions separated by two weeks in a randomised double blind fashion. Allergen inhalation challenge was performed four hours after dosing and FEV1 was measured for eight hours. The inhibitory activity of ZD2138 on the 5-lipoxygenase pathway was assessed by measurements of calcium ionophore-stimulated generation of LTB4 in whole blood ex vivo and by analysis of urinary LTE4 levels before administration of drug or placebo and at regular intervals after oral drug dosing and allergen challenge. RESULTS--ZD2138 produced no significant bronchodilatation or attenuation of the early or late asthmatic response, although there was 82% inhibition of whole blood generation of LTB4 in response to calcium ionophore stimulation and 52% reduction in urinary excretion of LTE4. CONCLUSIONS--In asthmatic subjects the 5-lipoxygenase inhibitor ZD2138 did not protect against allergen-induced asthmatic responses, despite substantial inhibition of 5-lipoxygenase. 相似文献
92.
Weekly subcutaneous recombinant human erythropoietin corrects anemia of progressive renal failure 总被引:1,自引:0,他引:1
PURPOSE: The purpose of this study was to analyze data retrospectively from our use of weekly subcutaneous recombinant human erythropoietin (rHuEPO) in predialysis and peritoneal dialysis patients with anemia. PATIENTS AND METHODS: All anemic patients with progressive renal failure (12 predialysis and seven home peritoneal dialysis) in whom subcutaneous rHuEPO therapy was begun at, or was reduced to, a weekly dose were studied retrospectively. Patients were not selected for, nor excluded from, these observations for any other reason. Hematocrit and endogenous creatinine clearance were monitored regularly, and no other new treatment for anemia was given except oral iron. Iron-deficiency anemia was considered improbable because of normal red blood cell mean corpuscular volume. Unfortunately, iron parameters were not monitored. RESULTS: The hematocrit increased 4 to 9 percentage points in 4 to 13 weeks in all but two patients who were initially treated with weekly doses, and a hematocrit of 31% was achieved in these patients within 6 to 12 weeks. The mean effective dose to accomplish this was 150 U/kg. All but three patients could be maintained on weekly doses at a hematocrit of 31% or higher. The mean effective dose was 75 U/kg. CONCLUSION: It is concluded that subcutaneous rHuEPO administered weekly can correct the anemia of predialysis and peritoneal dialysis patients. Weekly dosing is more convenient for patients and may be less costly for Medicare providers. 相似文献
93.
Narrative and procedural discourse in temporal lobe epilepsy. 总被引:2,自引:0,他引:2
Brian Bell Christian Dow E Ryann Watson Austin Woodard Bruce Hermann Michael Seidenberg 《Journal of the International Neuropsychological Society》2003,9(5):733-739
It is well established that some individuals with temporal lobe epilepsy (TLE) demonstrate language deficits at the single word level. However, discourse production rarely has been examined quantitatively within this group. This study compared adult TLE patients with an early seizure onset (< or = age 14 years, n = 27) to a control group (n = 28) on narrative and procedural discourse tasks. As a group, the TLE patients performed normally on the procedural discourse task, but differed significantly from the controls on several narrative discourse variables. At the individual level, 30% of the TLE patients versus 4% of the controls demonstrated impaired discourse ability (p and 0.01). Within this early onset TLE group, discourse performance was not associated with demographic or seizure history variables. Considering the cognitive domain, discourse performance correlated significantly with working memory. In summary, mild discourse dysfunction was present in a significant minority of early onset TLE patients, but this deficit was not closely associated with other language measures. Discourse ability and its neuropsychological, neuroanatomical and conversational speech correlates deserve further study in TLE patients. 相似文献
94.
95.
J. Bolton R. Abbott M. Kiely M. Alleyne S. Bell L. Stubbs M. Slevin 《Journal of human nutrition and dietetics》1992,5(2):79-84
This study set out to compare the long-term palatability of three oral sip-feed supplements. Sixty patients with various malignancies were randomized to receive one of three products—Build-Up, Fortimel and Fortisip. Participants were encouraged to take as much of the supplements each day for as long as they could manage. At the initial tasting, palatability and acceptability of the products was recorded and this was repeated throughout the trial period. Patients' reasons for discontinuing the trial were noted.
Build-Up was found to be the best-tolerated product of the three. It was taken for a significantly longer time than either Fortimel or Fortisip. There was an indication that Build-Up was more acceptable at the initial tasting than Fortisip but not Fortimel. A smaller proportion of patients stopped taking Build-Up due to flavour-related reasons compared to Fortisip but there was no significant difference between Build-Up and Fortimel. In all, 54% of the patients discontinued the trial for flavour-related reasons. Thirty-five per cent found that the sip-feeds they had been allotted unpalatable at the initial tasting, while 19% stopped the trial due to 'flavour fatigue'. Only 10% of the sample continued taking their allotted product for 90 days or more. 相似文献
Build-Up was found to be the best-tolerated product of the three. It was taken for a significantly longer time than either Fortimel or Fortisip. There was an indication that Build-Up was more acceptable at the initial tasting than Fortisip but not Fortimel. A smaller proportion of patients stopped taking Build-Up due to flavour-related reasons compared to Fortisip but there was no significant difference between Build-Up and Fortimel. In all, 54% of the patients discontinued the trial for flavour-related reasons. Thirty-five per cent found that the sip-feeds they had been allotted unpalatable at the initial tasting, while 19% stopped the trial due to 'flavour fatigue'. Only 10% of the sample continued taking their allotted product for 90 days or more. 相似文献
96.
Aim To elicit nurses' accounts of their involvement with nursing research and their interpretations of the meaning of these projects for their practice.
Background The links between research and practice development in health care are poorly understood and require further exploration in the light of the emerging research and development agenda within the National Health Service.
Methods Semi-structured interviews were conducted with 15 qualified nurses working on a Nursing Development Unit. The interviews were tape recorded, transcribed and analysed thematically.
Findings Data analysis identified two distinct groups—a core group of nurses actively engaged in the research projects and a peripheral group involved in data collection. The characteristics of the core group mirror the characteristics of those involved in non-research-based practice development activities.
Conclusions Engaging in research activities does not always result in the development of practice, however, there appears to be a link between practice development and critical thinking. 相似文献
Background The links between research and practice development in health care are poorly understood and require further exploration in the light of the emerging research and development agenda within the National Health Service.
Methods Semi-structured interviews were conducted with 15 qualified nurses working on a Nursing Development Unit. The interviews were tape recorded, transcribed and analysed thematically.
Findings Data analysis identified two distinct groups—a core group of nurses actively engaged in the research projects and a peripheral group involved in data collection. The characteristics of the core group mirror the characteristics of those involved in non-research-based practice development activities.
Conclusions Engaging in research activities does not always result in the development of practice, however, there appears to be a link between practice development and critical thinking. 相似文献
97.
98.
The inhibition of the oxidation of low density lipoprotein by (+)-catechin, a naturally occurring flavonoid. 总被引:4,自引:0,他引:4
H Mangiapane J Thomson A Salter S Brown G D Bell D A White 《Biochemical pharmacology》1992,43(3):445-450
(+)-Catechin inhibited the copper-catalysed oxidation of human low density lipoprotein (LDL) in a dose-dependent manner with complete inhibition at 20 micrograms/mL. The flavonoid at a concentration of 50 micrograms/mL also inhibited oxidation of LDL induced by the mouse transformed macrophage J774, human monocyte-derived macrophages and vascular endothelial cells isolated from human umbilical cords. LDL modified by copper-catalysed or cell-induced oxidation was endocytosed and degraded by human macrophages at a much greater rate than native LDL. LDL reisolated from copper or cell incubations in the presence of (+)-catechin was endocytosed and degraded at rates similar to native LDL. (+)-Catechin appeared to inhibit the uptake and degradation by macrophages of cell-modified LDL. The actions of (+)-catechin on cell-induced oxidation of LDL are consistent with the ability of flavonoids of similar structure to inhibit lipoxygenases and with a role for lipoxygenases in cell-induced modification of LDL in vivo. 相似文献
99.
Human GLUT4/muscle-fat glucose-transporter gene. Characterization and genetic variation. 总被引:5,自引:0,他引:5
J B Buse K Yasuda T P Lay T S Seo A L Olson J E Pessin J H Karam S Seino G I Bell 《Diabetes》1992,41(11):1436-1445
100.
New DEALEs: other approximations of life expectancy. 总被引:2,自引:0,他引:2