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101.
Age-related changes of exercise-induced plasma catecholamines and neuropeptide Y responses in normal human subjects. 总被引:3,自引:0,他引:3
E Winther Jensen K Espersen I L Kanstrup N J Christensen 《Acta physiologica Scandinavica》1992,144(2):129-133
Age-related plasma noradrenaline and neuropeptide Y were evaluated in seven young (mean +/- SD, 28 +/- 3 years) and seven elderly (64 +/- 8 years) normal subjects during rest and different work loads on a cycle ergometer. In the supine and the sitting position plasma noradrenaline and neuropeptide Y were almost identical in the two groups. Plasma neuropeptide Y did not increase during exercise at 100 W for 15 min. At this load plasma noradrenaline levels were higher in the older subjects (mean +/- SEM, 0.97 +/- 0.12 vs. 0.60 +/- 0.09 ng ml-1). There was a significant correlation between plasma noradrenaline and the relative work load at 100 W (r = 0.794, P = 0.0007). At 75% of maximal work load plasma noradrenaline and neuropeptide Y were higher in the young group (1.84 +/- 0.16 vs. 1.26 +/- 0.13 ng ml-1 (noradrenaline) and 38 +/- 4 vs. 22 +/- 5 pmol l-1 (neuropeptide Y)). In the elderly group plasma neuropeptide Y did not increase during exercise and showed a tendency to fall below basal level 5 min post-exercise. It is concluded, that plasma noradrenaline does not increase more in older subjects during exercise when correcting for the generally lower physical fitness in this group compared to younger subjects, and that plasma neuropeptide Y does not increase during exercise in older subjects, suggesting an age-reduced capacity in this system. 相似文献
102.
103.
A bioavailability study was performed on ten oophorectomized women in a randomized cross-over design. The absorption of tablets containing 2 mg of micronized oestradiol and 1 mg of micronized oestriol (Estrofem®) was compared to the absorption of the same micronized hormones administered in an aqueous suspension. Serum concentration values of oestradiol, oestriol and oestrone were measured by radioimmunoassay. The data obtained were analyzed both by univariate and multivariate analyses, and neither the serum concentrations at the various sample times, the maximum concentrations, the times for the maximum concentrations, nor the areas under the serum concentration curves disclosed any significant differences between the tablet and suspension administrations at the 5% level. The serum concentration values achieved by giving 2 mg of oestradiol and 1 mg of oestriol were of the same magnitude or higher than those of the normal menstrual cycle. 相似文献
104.
Arnt Jørn Christensen Anne Vibeke Hyttel John 《Naunyn-Schmiedeberg's archives of pharmacology》1985,329(2):101-107
Summary Behavioural effects on dopaminergic transmission of a phenylindane derivative, Lu 19-005 [(±)-trans-3-(3,4-dichlorophenyl)-N-methyl-l-indanamine, HCl], with potent inhibitory effect on dopamine (DA), noradrenaline (NA) and serotonin (5-HT) uptake in rats and the effect on DA, NA and 5-HT activity in mice have been studied and compared with those of other known DA, NA and 5-HT uptake inhibitors with different selectivity ratios.Lu 19-005 induced stereotyped behaviour after parenteral and oral administration with a duration of action of more than 24 h. The stereotyped licking and biting induced by Lu 19-005 was antagonized by reserpine and cis(Z)-flupentixol, but not affected by prazosin, p-chlorophenylalanine and -methyl-p-tyrosine pretreatments. Metergoline slightly facilitated the onset of stereotypy. Lower doses of Lu 19-005 induced ipsilateral circling in unilaterally 6-hydroxy-DA-lesioned rats. Finally, Lu 19-005 antagonized the catalepsy induced by perphenazine. In mice, Lu 19-005 potentiated the apomorphine-induced gnawing, reversed tetrabenazine-induced ptosis and potentiated the behavioural effects of 5-HTP within a similar dose range.The effects of Lu 19-005 were compared with those of other reference compounds. Nomifensine had qualitatively similar effects in rats although of much shorter duration. In mice, nomifensine selectively reversed tetrabenazine-induced ptosis. Weaker effects in all test models were found with bupropion, LR 5182 and GBR 13.069, compounds with inhibitory effect on DA and NA uptake. The DA-, NA-and 5-HT-uptake inhibitor diclofensine, however, had no effect in rats except in the 6-hydroxy-DA-circling test and had low potency in mice. The specific 5-HT-and NA-uptake inhibitors citalopram and talsupram, respectively, were ineffective in all rat models. They selectively potentiated 5-HTP or reversed tetrabenazine0induced ptosis in mice, respectively, as expected according to their in vitro profile. These results indicate that effect on DA mechanisms are responsible for the behavioural activity of the test compounds in the rat models and that the circling model is the most sensitive. Since DA may be involved in some depressive states Lu 19-005 could be an attaactive new antidepressant as it combines the pharmacological profile of established antidepressants (effect on NA and/or 5-HT uptake) with equipotent activity on DA uptake. 相似文献
105.
S. Bondesen MD H. Christensen MD K. Lindorff-Larsen MD Dr. O. B. Schaffalitzky De Muckadell MD 《Digestive diseases and sciences》1985,30(5):440-444
The effect of exogenous bile salts on plasma concentrations of secretin was studied by infusion of chenodeoxycholate, cholate, glycocholate, and taurocholate into the duodenum of normal subjects. The effect of endogenous bile on plasma secretin was studied by ingestion of a liquid test meal, by reinfusion of postprandial duodenal aspirates with known contents of bile salts, and by stimulation of gallbladder contraction by cholecystokinin. Each experiment was performed in groups of seven subjects. The relative secretin-releasing potencies of glycocholate, cholate, taurocholate and chenodeoxycholate (2.25 mmol) were 1.01.31.93.2. Hydrochloric acid (0.5 mmol) was, on a molar basis, approximately ten times more potent than sodium cholate. The effect of taurocholate was diminished when a liquid meal was used as vehicle instead of saline. Endogenous bile did, in no circumstance, elicit release of secretin. It is concluded that although bile salts have the ability to stimulate secretin release, endogenous secretin release is of minor, if any, importance for secretin release when physiological conditions are approached.This study was supported by grants from the Danish Hospital Foundation for Medical Research, Region of Copenhagen, The Faroe Islands and Greenland (J.nr. 78/45 and 79/48) and Borgen Legatet. 相似文献
106.
Christensen P Kragh-Sørensen P Sørensen C Thomsen HY Iversen AD Christensen KS Hüttel M Tønnesen E 《Convulsive therapy》1986,2(3):145-150
Electroencephalogram-monitored electroconvulsive therapy (ECT) was carried out in 20 depressed inpatients. Before treatment, patients were randomly allocated to treatment using etomidate (Hypnomidat) (n = 10) or thiopentone (n = 10) for anesthesia. The groups were matched for sex, age, weight, and type and severity of depression. The seizure duration (seconds) was measured by electroencephalography (EEG), and the electrical energy (Joules, J) was determined for each treatment. A ratio of seizure duration:electrical energy (s/J) was computed. Both seizure duration and seizure duration:electrical energy were greater in the etomidate group than in the thiopentone group, whereas electrical energy did not differ significantly. The number of treatments in the etomidate group did not differ from that in the thiopentone group, as may be expected, perhaps because of the small size. 相似文献
107.
Daniel I. Rosenthal M.D. Steve Christensen Roger H. Emerson M.D. 《Skeletal radiology》1984,11(2):128-132
Handedness is a basic property of spirals. In many cases it is possible to determine whether spiral fractures are right or left handed by analysis of radiographs. Spiral fractures of the tibia show striking bilateral symmetry, with right-handed spirals predominating on the left side of the body, and left-handed spirals on the right. 相似文献
108.
Madsen Christina Merete Tvede Bisgaard Sara Kjær Primdahl Jette Christensen Jeanette Reffstrup von Bülow Cecilie 《Journal of occupational rehabilitation》2021,31(4):866-885
Journal of Occupational Rehabilitation - Purpose To present an overview of the evidence of the effect of job loss prevention interventions, aiming to improve work ability and decrease absenteeism... 相似文献
109.
Characterization of Salmonella enterica serovar gallinarum biovars gallinarum and pullorum by plasmid profiling and biochemical analysis 总被引:4,自引:0,他引:4
One-hundred-and-five strains of Salmonella enterica serovar gallinarum, biovar pullorum and 43 strains of biovar gallinarum were characterized by biochemical reactions, and 95 strains of biovar pullorum and 32 strains of biovar gallinarum were examined for plasmid content. Twenty-one (66%) of the strains classified as biovar gallinarum contained a 85-kb virulence plasmid. Six of these strains also contained a 2.5-kb plasmid. Ten strains (31%) were without plasmids. Ninety-three strains (98%) belonging to biovar pullorum contained the virulence plasmid and, in addition, these strains contained from one to four small plasmids. Two strains did not contain plasmids. Restriction enzyme digestions of the virulence plasmid showed three different profiles, two of which were common for biovars gallinarum and pullorum. It is suggested that the phenotypic diversity of biovars gallinarum and pullorum, as well as the diversity of plasmid profiles of biovar pullorum, could be used as epidemiological markers. Differences in phenotypic characters were not related to plasmids demonstrated in biovars of S. enterica serovar gallinarum. 相似文献
110.
J Berglund L Bondesson S B Christensen A S Larsson S Tibblin 《Acta chirurgica Scandinavica》1990,156(6-7):433-438
Of 287 consecutive patients, surgically treated at our department for benign, nontoxic goitre during a six-year period, 261 could be followed up, on average, 8.0 years postoperatively. Unilateral surgical procedures had been used in 199 patients, subtotal thyroidectomy in 62. 29 patients were treated with thyroxine (T4) immediately postoperatively ("recurrence prophylaxis"); in the other patients thyroxine was only given in cases of hypothyroidism (significant increase of s-TSH). 26 patients had a goitre recurrence 0.5-10 years after surgery; of these 3 had got T4 as "recurrence prophylaxis" and 23 had not. There was no significant difference between patients with and without T4 postoperatively regarding the rate of recurrence. Of 55 patients treated with subtotal thyroidectomy, 33 had postoperative latent (n = 26) or manifest (n = 7) hypothyroidism. Only 13 of 177 patients operated on unilaterally developed hypothyroidism; two of these had Hashimoto's thyroiditis. All cases of hypothyreosis except 4 were detected within the first 12 months of follow-up. This study indicates that routine use of thyroxine as prophylaxis against recurrence after surgery for benign nontoxic goitre can be strongly questioned and that the risk of hypothyroidism is high after subtotal thyroidectomy. 相似文献