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21.
The dental awareness and needs of a population with Parkinson's disease were assessed by means of postal questionnaires sent to members of Parkinson's disease societies of Belfast and London. A total of 228 valid replies were received representing a response rate of 31%. Results showed that dental problems were reported often, xerostomia and burning sensation being at least twice that of the general population. Satisfaction with dental care was high although it was significantly reduced in those with loose dentures and burning sensation. The results of this study support a greater participation by dentists in the planning and provision of healthcare for sufferer of Parkinson's disease.  相似文献   
22.
The effects of forskolin and cholera toxin on the regulation of cAMP release were studied in a neurotensin-secreting rat C-cell line. The interaction of these agents with norepinephrine, a potent neurotensin secretagogue, was also investigated. Forskolin stimulated cAMP release 10(2)-10(3) fold while it increased neurotensin release 2-3 fold. Cholera toxin caused a 10(2)-10(3) fold increase in cAMP release and had no effect on neurotensin release. We conclude that the 44-2 C-cells provide a new model for studying the regulation of the concomitant (via forskolin) or independent (via cholera toxin) secretion of cyclic AMP and/or neurotensin.  相似文献   
23.
A highly active inhibitor of the binding of estrone and estradiol-17β to rat alpha-fetoprotein is demonstrated for the first time in embryo, immature and adult rat sera as well as in fetal and adult human sera. The competitive character and the narrow specificity of this inhibition effect is shown. The major compound responsible for this activity is isolated by successive column Sephadex LH20 and thin layer chromatography : it is characterized as a nonpolar, nonphenolic, dialysable and thermostable substance, unreactive towards anti-estrone and anti-estradiol-17β anti-bodies. The possible biological role of an endogenous non-estrogen ligand of rodent fetoproteins is discussed.  相似文献   
24.
Sodium selenite (Na2SeO3) was tested for its sister-chromatid exchange (SCE)-inducing ability in human whole blood cultures and for the effect of its co-exposure with methyl methanesulfonate (MMS) or N-hydroxy-2-acetylaminofluorene (N-OH-AAF) on SCE frequency. Long exposure times (77 h and 96 h) to 3.95 X 10(-6) M Na2SeO3 resulted in cell death as measured by mitotic indices, but mitotic figures were present after exposure to higher concentrations for a shorter time (19 h). High Na2SeO3 concentrations (7.90 X 10(-6) and 1.19 X 10(-5) M) resulted in a three-fold increase in the SCE frequency above background level (6--7 SCEs/cell). Exposure of lymphocytes to 1 X 10(-4) M MMS for the last 19 h of culture yielded an average SCE frequency of 30.17 +/- 0.75 while a similar exposure to 2.7 X 10(-5) M N-OH-AAF resulted in 13.61 +/- 0.43 SCEs/cell. Simultaneous addition of the high Na2SeO3 concentrations and MMS or N-OH-AAF to the cultures resulted in SCE frequencies that were 25--30% and 11--17%, respectively, below the sum of the SCE frequencies produced by the individual compounds.  相似文献   
25.
Les interactions h?te-parasito?de ont été abordées dans le cas du systèmeTrichomalopsis peregrina G. (Pteromalidae) et son h?te grégaireEuproctis chrysorrhoea L. (Lymantriidae), au cours de la phase diapausante des chenilles dans les nids d'hiver tissés par ce ravageur. Un échantillon de 1 432 nids d'hiver a été récolté dans 8 peuplements de chênes dans la région toulousaine durant l'hiver 1988. Le volume du nid a été utilisé comme estimateur du nombre de chenillesh?tes dans les nids et la réponse du parasito?de a été comparée à celle prévue par la théorie de la stratégie optimale de recherche. Les principaux résultats sont les suivants:
(i)  les parasito?des présentent une réponse agrégative typique, les plus fortes densités d'h?tes correspondant au plus grand nombre de parasito?des sortant des nids;
(ii)  contrairement à la théorie, les taux de parasitisme apparent varient en sens inverse des effectifs de chenilles par nid;
(iii)  ces résultats suggèrent l'existence d'une accessibilité limitée des chenilles, l'activité parasitaire s'exer?ant sur les chenilles proches de la surface du nid.
Host-parasitoid interactions are reviewed in the case ofTrichomalopsis peregrina G. (Pteromalidae) and its aggregated host,Euproctis chrysorrhoea (Lymantriidae) during the arrest of development of the caterpillars in the winter nest spun by this forest pest. A sample of 1,432 winter nests in 8 oak groves near Toulouse, Haute-Garonne, France were collected during the winter 1988. The volume of the winter nests has been used to estimate the number of larvae in nests. The response of the parasitoid has been compared with the optimal searching theory for parasitoids. The main results are: (i) Parasitoids present an aggregative response; to a higher density of host larvae corresponds a higher number of apparent attacks; (ii) in contrast with that theory, the apparent rate of parasitism is inversely density dependent with respect to caterpillar density in the nest; (iii) these results suggest that the access of the parasito?d to the caterpillars is limited to the proximity of the nest surface.  相似文献   
26.
E E Keha  H Ronft  G B Kresze 《FEBS letters》1982,145(2):289-292
45Ca2+ incorporated in response to glucose was selectively mobilized from the beta-cell-rich pancreatic islets of ob/ob-mice after raising the intracellular Na+ by removal of K+ or addition of ouabain or veratridine. Also studies of insulin release indicated opposite effects of glucose and Na+ on the intracellular sequestration of calcium. The fact that glucose inhibits insulin release induced by raised intracellular Na+ indicates that this sugar can lower the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+] might well explain previous observations of an inhibitory component in the glucose action on the 45Ca2+ efflux.  相似文献   
27.
Flavonoid patterns of several provenances ofVeronica triloba, V. sublobata, andV. hederifolia s. str. have been investigated. 7-0-glucuronides of apigenin and luteolin as well as of 6-substituted (6-hydroxyluteolin and hispidulin) and 3′-methylated (chrysoeriol) derivatives represent characteristic accumulation tendencies in theV. hederifolia group. The three species show slightly different flavonoid profiles.V. hederifolia exhibits a cumulative pattern of all compounds occurring either inV. triloba orV. sublobata, thus supporting the hypothesis of an allopolyploid origin ofV. hederifolia.  相似文献   
28.
Abstract. Responses to red light irradiation of discrete areas along the intact, etiolated oat seedling indicate that illumination of the region around the coleoptilar node results in maximal coleoptile growth stimulation and mesocotyl growth suppression. Quantitation of the fibre optic properties of these etiolated tissues shows that the amount of axially transmitted light is log linear as a function of distance for both the mesocotyl and coleoptile (plus primary leaf). Using the fibre optic properties of the tissues to predict the response of the etiolated seedling to defined illumination fields allows one to localize two sites of photoperception: although the mesocotyl response pattern can be explained by the action of a single site found near the top of the mesocotyl itself, the coleoptile response depends on irradiation of both the mesocotyl site and an additional site located just above the node. The very low- and the low-fluence responses of etiolated oats independently predict similar regions of the seedling as sites of photo-perception. The fibre optic properties of the seedling could allow the seedling to increase the effective light signal received by the photosensitive area significantly.  相似文献   
29.
DNA fork displacement rates were measured in three lines of Bloom's syndrome cells and in a normal diploid fibroblast line. Fork displacement rates in Bloom's cells were approx. 55–65% of the rate in normal fibroblasts.  相似文献   
30.
Sylvie Secretan 《Geobios》1980,13(3):411-433
Are the Eumalacostraca issued from a model of Crustacea which the carapace would have disapeared later on in some of them, and persisted in others, or from one without carapace that some of its decendants would have acquired? In the two instances this ancestor would goes far back, seeing that, already, in the Devonian, Syncarida, Stomatopoda, Phyllocarida and Eocarida were differenciated. With regard to the preliminary survey on a fine material of Syncarida from the Stephanian of the region of Autun, comparisons between two models of Crustaceans from which the cephalon includes only sensorial and gnathal segments, without adjunction of any thoracic metamere, allow to specify the notion of carapace, and to surround the question. The great oldness of the origin of the phyla possessing or not possessing a carapace seems to exclude the hypothesis of a passing over from one model to the other and suggests a representation of the common ancestor which have to be searched in the Cambrian period.  相似文献   
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