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Clonidine (10 micrograms X kg-1) reduced by almost 50% the increase in plasma neuropeptide (NPY)-like immunoreactivity (-LI) induced by preganglionic nerve stimulation at 8 Hz. This effect was reversed by yohimbine (1 mg X kg-1) which caused a three-fold increase of the plasma NPY-LI. Prazosin (1 mg X kg-1) had no such effect. Guanethidine (5 mg X kg-1) reduced the stimulation-evoked increase in plasma NPY-LI. It is concluded that the release of NPY-LI evoked by nerve stimulation from sympathetic nerve terminals is controlled by a presynaptic alpha 2-adrenoceptor-mediated mechanism. 相似文献
4.
Catarina Gonzalez da Silva Karl Magnus Petersson Luís Faísca Martin Ingvar Alexandra Reis 《Journal of clinical and experimental neuropsychology》2004,26(2):266-277
Semantic verbal fluency tasks are commonly used in neuropsychological assessment. Investigations of the influence of level of literacy have not yielded consistent results in the literature. This prompted us to investigate the ecological relevance of task specifics, in particular, the choice of semantic criteria used. Two groups of literate and illiterate subjects were compared on two verbal fluency tasks using different semantic criteria. The performance on a food criterion (supermarket fluency task), considered more ecologically relevant for the two literacy groups, and an animal criterion (animal fluency task) were compared. The data were analysed using both quantitative and qualitative measures. The quantitative analysis indicated that the two literacy groups performed equally well on the supermarket fluency task. In contrast, results differed significantly during the animal fluency task. The qualitative analyses indicated differences between groups related to the strategies used, especially with respect to the animal fluency task. The overall results suggest that there is not a substantial difference between literate and illiterate subjects related to the fundamental workings of semantic memory. However, there is indication that the content of semantic memory reflects differences in shared cultural background--in other words, formal education--, as indicated by the significant interaction between level of literacy and semantic criterion. 相似文献
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Occurrence of anti-C1q antibodies in IgA nephropathy 总被引:1,自引:0,他引:1
Gunnarsson I; Ronnelid J; Lundberg I; Jacobson S 《Nephrology, dialysis, transplantation》1997,12(11):2263-2268
Background: The pathogenic mechanisms and the antigens
involved in the establishment and progress of IgA nephropathy are unknown.
As antibodies against C1q have been reported to correlate with SLE
nephritis, we analysed the occurrence of these antibodies in IgA
nephropathy in order to investigate the possibility of pathogenetic
similarities in these renal disorders. Methods: The
occurrence of IgA- and IgG anti-C1q antibodies (anti-C1q) were determined
by ELISA in patients with IgA nephropathy (n=36) and SLE nephritis (n=37),
diseases both known to be associated with circulating immune complexes.
Levels of these antibodies were also determined in two other glomerular
diseases, i.e. idiopathic membranous glomerulo-nephritis (n=7) and minimal
change disease (n=2), in which circulating immune complexes are usually not
present, and in 40 healthy controls. Results: IgA
anti-C1q was observed in increased titres in 11/36 of the patients with IgA
nephropathy, in 2/37 of the patients with SLE nephritis (both with
proliferative disease) and in 1/9 of the patients with membranous and
minimal change disease (P<0.001). Increased titres of IgG anti-C1q
were observed in 1/36 of the patients with IgA nephropathy, in 17/37 of the
patients with SLE nephritis and in 0/9 of the patients with membranous and
minimal change disease (P<0.001). There were no correlations between
the levels of anti-C1q antibodies and clinical parameters such as degree of
proteinuria, haematuria, or renal function. Nor was there any correlation
to the concentration of C3a and the terminal complement complex (TCC) in
patients with IgA nephropathy. Conclusions: The
occurrence of anti-C1q antibodies in both IgA nephropathy and SLE
nephritis, albeit of different predominating isotypes, indicates the
possibility of a similar pathogenic mechanism involved in these renal
disorders. The occurrence of IgA anti-C1q antibodies in patients with IgA
nephropathy has to our knowledge not previously been reported. 相似文献
8.
Mark C. K. Yang Ronald G. Marks William B. Clark Ingvar Magnusson 《Journal of clinical periodontology》1992,19(2):77-83
Abstract Several statistical models that have been suggested in the periodontal literature for describing longitudinal attachment level changes, such as the gradual loss, single-burst, multiple-burst, and random walk models as well as other models introduced in this paper are compared by their power to predict future attachment loss. The data used in this analysis is from 1061 sites of 8 subjects, with moderate to severe periodontal disease, monitored monthly for about a year. This study found that none of the suggested models could significantly outperform the naive mean predictor, which predicts the future attachment level from the past mean. It was also found that no single model, such as the burst, gradual, or random walk, together with measurement error can fully explain the variation in the data. These results indicate that in the course of one year, the attachment level change may not follow the same model. Consequently, a model that fits well to past data cannot be accurately extended to the future. 相似文献
9.
G Lindstedt E Nystr?m P A Lundberg E Johansson R Eggertsen 《Scandinavian journal of primary health care》1992,10(3):192-197
In order to assess the diagnostic outcome of a screening for primary hyperparathyroidism (PHPT) in an elderly population, we determined ionized calcium in serum from 368 individuals participating in a health control at M?lnlycke Primary Care Centre (200 women, 168 men; age range 75-95 years); four-fifths of the individuals living in their homes, the remainder in homes for aged or nursing homes. Intact parathyroid hormone was determined in the samples with oinized calcium concentration greater than mean + 3SD of the truncated population sample, and these individuals were also recalled for another blood sample. Moderate hypercalcaemia, probably due to PHPT, was found in eight individuals (2% of the complete sample, 3% of the women), five having neuropsychiatric or neuromuscular symptoms consistent with PHPT. Surgical intervention is probably indicated in only a small proportion of elderly patients. We conclude that optimal benefits in relation to costs of screening for PHPT in old people will depend on the availability of a safe and simple pharmacological treatment that could determine any causal relationship between hypercalcaemia and symptoms. 相似文献
10.
M Frankenhaeuser U Lundberg M Rauste von Wright J von Wright G Sedvall 《Pharmacology, biochemistry, and behavior》1986,24(6):1521-1525
Concentrations of the serotonin metabolite 5-hydroxyindole acetic acid (5-HIAA), the dopamine metabolite homovanillic acid (HVA) and the noradrenaline metabolite 4-hydroxy-3-methoxyphenyl glycol (HMPG) were determined in urine samples from healthy male and female students by mass fragmentography. Urine samples were obtained after a demanding examination (mental stress) and a day of ordinary school work (control condition). Self-ratings were obtained of feelings induced by the examination, and of habitual psychosomatic symptoms. The results for both sexes showed that the examination stress induced a significant increase of HVA and HMPG excretion, but not of 5-HIAA. The males excreted significantly more of each of the metabolites than the females. The pattern of correlations between metabolite levels and psychological and psychosomatic variables were strikingly different for the two sexes. 相似文献