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991.
SL Schiffelers EM Brouwer WH Saris MA van Baak 《Canadian Metallurgical Quarterly》1998,47(12):1462-1467
The purpose of the study was to investigate whether the increase in energy expenditure and lipid oxidation during beta1-adrenergic stimulation is caused by the concomitant increase in lipolysis. Twelve healthy male subjects participated in three trials: no-LIP/-, inhibition of lipolysis by pretreatment with acipimox followed by saline infusion; -/BETA, no pretreatment, with dobutamine infusion to stimulate beta1-adrenoceptors; and no-LIP/BETA, pretreatment with acipimox followed by dobutamine infusion. Inhibition of lipolysis did not affect baseline energy expenditure, but decreased lipid oxidation and increased carbohydrate oxidation. Energy expenditure and lipid oxidation increased significantly during beta1-adrenergic stimulation, but this increase was significantly smaller when lipolysis was inhibited ([baseline v infusion period] energy expenditure: -/BETA, 5.15 +/- 0.16 v 6.11 +/- 0.26 kJ/min, P < .001; no-LIP/BETA, 5.28 +/- 0.17 v 5.71 +/- 0.19 kJ/min, P < .01; lipid oxidation: -/BETA, 0.059 +/- 0.004 v 0.073 +/- 0.006 g/min, P < .01; no-LIP/BETA, 0.034 +/- 0.005 v 0.039 +/- 0.006 g/min, P < .05). Baseline plasma glycerol and nonesterified fatty acid (NEFA) concentrations decreased after inhibition of lipolysis. Glycerol and NEFA increased significantly during beta1-adrenergic stimulation alone (glycerol, 65.0 +/- 5.3 v 117.0 +/- 10.9 micromol/L; NEFA, 362 +/- 24 v 954 /- 89 micromol/L; both P < .001). Concomitant administration of acipimox prevented a substantial part of the increase in lipolysis during beta1-adrenergic stimulation, but the increase in plasma glycerol and NEFA remained significant (glycerol, 40.4 +/- 2.2 v 44.8 +/- 2.2 micromol/L; NEFA, 118 +/- 18 v 160 +/- 19 micromol/L; both P < .05). In conclusion, a reduced availability of plasma NEFA was associated with a reduced increase in energy expenditure and lipid oxidation during beta1-adrenergic stimulation in man. 相似文献
992.
EM Christensen A Gjerris C Gjerris JK Larsen 《Canadian Metallurgical Quarterly》1998,160(37):5353-5357
A cohort of 158 patients was identified from 723 patients admitted in 1990 or treated as outpatients in 1991 for affective disorders in three university hospitals in Copenhagen, covering a well-defined catchment area. The cohort was subclassified for seasonal pattern according to DSM-III-R. Meteorological data of temperature, hours of sunshine, rainfall and wind-velocity expressed as mean values/month were obtained from the Institute of Meteorology in Copenhagen. There was no relationship between the annual dis- tribution of affective episodes and meteorological data, neither in the total cohort nor in the subgroup of patients with seasonal patterns The present study does not support the hypothesis that a relation exists between start of a new episode and the season or climatic condition. 相似文献
993.
P. L. Cabot F. A. Centellas J. A. Garrido P. T. A. Sumodjo A. V. Benedetti R. Z. Nakazato 《Journal of Applied Electrochemistry》1991,21(5):446-451
The effect of consecutive cyclic polarization in de-aerated 0.5 M NaOH solutions on the surface microstructure of mechanically polished Cu-Al-Ag alloys of different compositions and heat treatments has been studied using optical microscopy, SEM and EDS. The current peaks of the cyclic polarization curves do not depend on the alloy composition in the composition range studied. The repetitive potential scans between H2 and O2 evolution in alkaline media lead to preferential dissolution of aluminium, the roughness and phase composition of the surface of the alloys changing significantly. The quasistationaryI-E curves of the different Cu-Al-Ag alloys studied consist in the superposition of the quasistationaryI-E curves of high-purity Cu and Ag, the EDS microanalysis showing that aluminium is not present on the surface of the alloy in these conditions. 相似文献
994.
995.
OBJECTIVE: To compare betamethasone with placebo as an adjuvant to antibiotic therapy in the treatment of acute exudative pharyngitis. METHODS: The study was a randomized, doubled-blind, placebo-controlled, single-center, parallel, outpatient clinical trial. After consent was obtained, each patient was asked to rate his or her pain on a 10-cm numbered visual analog scale (VAS; 0-10). All of the patients received injectable benzathine penicillin. If allergic to penicillin, they were started on a 10-day course of polyenteric-coated erythromycin (PCE). Each patient was randomized to receive either i.m. betamethasone or i.m. placebo. All patients were contacted by telephone at 24 and 48 hours by one of the study investigators and asked to rate their pain based on another VAS. If their pain was not resolved by 48 hours, they were called again daily between the third and seventh days after the initial visit to determine the time of pain resolution. RESULTS: A total of 92 patients were enrolled in the study, with 46 randomized to receive placebo and 46 to receive betamethasone. Eight patients were excluded from the statistical analysis because of inability to obtain follow-up. Demographic comparison showed that gender distributions, ages, mean initial pain scores, mean times to the first and second follow-up calls, and treatment regimens were similar in the 2 groups. There were significantly better pain scores for the betamethasone group at first follow-up (p = 0.0005), at second follow-up (p = 0.004), and in number of hours until relief of pain (p = 0.004). When only those patients with a positive culture for a streptococcus species were analyzed, there also were significant reductions in pain score at the first (p = 0.006) and second (p = 0.02) follow-up visits. CONCLUSION: Pain relief was greater and more rapid in patients treated with betamethasone as an adjuvant therapy in acute exudative pharyngitis. 相似文献
996.
JB Whitney A Leder J Lewis RA Popp C Paszty EM Rubin WR Shehee TM Townes O Smithies 《Canadian Metallurgical Quarterly》1998,36(1-2):65-77
Because of its high sensitivity, bioluminescence (BL) is an excellent alternative to radioactive quantitation of cytokine RT-PCR-derived products. BL also allows detection of amplicons at cycle numbers not normally detectable using radioactivity. No direct comparisons between these two methods have been made. In this study, the sensitivities of BL using recombinant aequorin, a flash-type luminescent tag capable of detecting signal to attomolar (10(-18) M) levels and radio imaging (RI) were directly compared. In addition, the application of BL for detecting cytokine message from biologic samples was examined. BL was 30- to 60-fold more sensitive than RI in detecting human IL-2 and CD3delta amplicons. This difference was particularly found during low cycle PCR, but was less at higher cycle numbers. The ability of BL to detect differences in cytokine message in stimulated and unstimulated human peripheral blood mononuclear cells was also evaluated. Using linear regression analysis, we observed up to 5,000-fold increases in RT-PCR amplified-mRNA in stimulated cells for IL-1alpha, IL-1beta, IL-2, IL-4, IL-5, IL-6, IL-10 and GM-CSF compared to unstimulated cells. Changes in CD3delta, TNF alpha or IL-12 were not observed or quantitated. We present a novel aequorin-based application of bioluminescent technology to directly quantitate RT-PCR amplicons and to investigate the induction of human cytokine expression. Significant advantages of this sensitive bioluminescent method compared with radioactive methods are its abilities to quantitate amplicons in a PCR cycle range where linear detection is most robust and to analyze products in an automated, open-architecture microtiter plate format. 相似文献
997.
EM Kilbourne 《Canadian Metallurgical Quarterly》1998,279(22):1828-1829
998.
JP van Pelt EM de Jong ES de Bakker PC van de Kerkhof 《Canadian Metallurgical Quarterly》1998,11(2):70-79
The prophylactic effect of intravenous immunoglobulin (GB-0998) on the recurrent acute otitis media, bronchitis and bronchopneumonia in IgG 2 deficient infants was investigated in a multicenter trial. GB-0998 was administered 6 times every 4 weeks. The doses were 300 mg/kg wt. during the first treatment, followed by 5 doses of 200 mg/kg wt. The results indicated that GB-0998 was effective in the prophylaxis of the recurrent infection of acute otitis media, bronchitis and bronchopneumonia in infancy with IgG 2 deficiency and/or IgG 2 antibody deficiency specific for Streptococcus pneumoniae. 相似文献
999.
1000.
Evaluation of a competitive ELISA for detection of antibodies against avian influenza virus nucleoprotein 总被引:3,自引:0,他引:3
BACKGROUND: Growth hormone (GH) has been shown to promote wound healing and to improve protein metabolism in burned patients. Through immunomodulation, GH has also protected rats infected with Salmonella typhimurium and mice infected with Escherichia coli. In spite of advances in the management of patient care for those with thermal injuries, high mortality rates of burned patients as a result of infections are of special concern. An improvement in the resistance of burned patients to certain infections will make the beneficial role of GH very clear. In this study, therefore, the immunomodulating effects of recombinant human GH (rhGH) in thermally injured mice exposed to opportunistic herpesvirus infections were investigated. METHODS: (1) Burned mice, exposed to herpes simplex virus type 1 (HSV-1), were treated subcutaneously with rhGH (4 mg/kg) and observed for 21 days to determine the protective antiviral effect of rhGH. (2) Because of reports describing a lack of interferon-gamma (IFN-gamma) responsiveness in burned mice, the IFN-gamma-producing ability of the splenic mononuclear cells (SMNC) from burned mice treated with rhGH was examined. (3) Because the generation of burn-associated suppressor macrophages that can inhibit the IFN-gamma production by SMNC has been previously described, the suppressor cell activities of macrophages from burned mice treated with rhGH were examined. RESULTS: After exposure to lethal amounts of HSV-1, mice treated with rhGH displayed a reduced mortality rate compared with control mice treated with saline. SMNC from burned mice treated with rhGH produced IFN-gamma, whereas this cytokine was not produced by SMNC from burned mice treated with saline. Also, an inhibition of the generation of burn-associated suppressor macrophages was displayed in burned mice treated with rhGH. CONCLUSION: Exogenous administration of rhGH caused an improvement in the resistance of burned mice to HSV-1 infection. In burned mice treated with rhGH, the impaired IFN-gamma responsiveness was restored and the generation of burn-associated suppressor macrophages was inhibited. IFN-gamma, a typical antiviral cytokine induced by rhGH through the regulation of the suppressor macrophage generation, may therefore play a role in the protection of burned mice infected with a lethal amount of HSV-1. 相似文献