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101.
The urinary excretion of C21- and C19-steroids was investigated in female babons (Papio hamadryas) treated with the ovulation inhibitor Ovosiston (mestranol + chlormadinone-acetate), in comparison with an untreated control Group Urinary C21-steroid excretion was not significantly altered by Ovosiston. 17-Ketosteroids were decreased, predominantly 11-oxygenated compounds. 相似文献
102.
Two experiments were performed with ovariectomized female rats in an attempt to determine whether estradiol and dihydrotestosterone work synergistically in the brain to activate mounting behavior. In Expt 1, performed in Göteborg, it was found that females treated daily with 2 μg estradiol benzoate (EB) combined with 500 μg dihydrotestosterone (DHT) displayed significantly more mounts with pelvic thrusting than other females treated with the oil vehicle, 500 μg DHT, or 2 μg EB. The behavior of rats receiving EB + DHT was indistinguishable from that of yet another group of females which received 200 μg testosterone propionate (TP). In Expt 2, performed in Rotterdam, it was found that ovariectomized female rats treated with either 200 μg TP or 2 μg EB + 200 μg dihydrotestosterone propionate (DHTP) mounted significantly more than females treated with 2 μg EB. Both clitoral size and the growth of cornified papillae on the glans clitoris were stimulated by the administration of TP or EB + DHTP. However, in no group was the frequency of mounting affected by anesthetization of the clitoris and external vagina with lidocaine paste. Lordosis quotients of females treated with EB + DHTP were significantly lower than in rats receiving either EB or TP, again regardless of whether or not the genital region was anesthetized. It is concluded that the effects of DHT on estradiol-induced mounting and receptivity most likely result from the action of this androgen on the brain, and not from the stimulatory effect which DHT may exert on genital sensory receptors. 相似文献
103.
R. Håkanson F. Sundler A. Nobin N. -O. Sjöberg L. Edvinsson L. -I. Larsson 《Cell and tissue research》1974,150(2):281-290
Summary In the mammalian pituitary formaldehyde-ozone treatment induces strong fluorescence in the cells of the pars intermedia and moderate to strong fluorescence in numerous cells of the pars distalis. Maximum excitation is at 370–375 nm and maximum emission at 495–505 nm. The properties of the cellular fluorescence are indistinguishable from those of tryptamine or peptides with NH2-terminal tryptophan. From chemical analysis such peptides seem to occur abundantly in the mammalian pituitary. The concentration of these peptides agrees very well with the number and fluorescence intensity of the cells in all species studied. Furthermore, the tryptophyl peptides in the various parts of the pig pituitary have a distribution quite parallel to that of the fluorescent cells. As we have failed to detect tryptamine in the pituitary, we conclude that the formaldehyde-ozone-induced fluorescence in the adenohypophysis reflects the presence of tryptophyl peptides.This study was supported by grants from the Swedish Medical Research Council (04X-1007; 04X-3764), the Ford Foundation, Harald and Greta Jeanssons stiftelse and Riksföreningen mot Cancer (660-K73-01X).For brevity occasionally referred to as tryptophyl peptides. 相似文献
104.
105.
106.
107.
A method for the selective degradation of polysaccharides containing uronic acid residues is described. It involves methylation of hydroxyl and carboxyl groups, base-catalysed elimination, and mild hydrolysis with acid. The degraded product is etherified with trideuteriomethyl or ethyl groups and hydrolysed, and the resulting mixture of etherified sugars is analysed, as the alditol acetates, by g.l.c.—m.s. Comparison of this analysis with the methylation analysis of the original polysaccharide gives information on the nature of the sugar residues on either side of the uronic acid residue. 相似文献
108.
By addition of 1-(14)C-sodium acedate to the growth medium of Nocardia asteroides, it can be shown that the lipid content increases during the exponential phase, but does not vary during the stationary phase of the growth. Nocardic acid biosynthesis from the medium molecular weight fatty acids occurs chiefly during te stationary phase. As these compounds are localised in the cell walls, it becomes evident that the lipid envelope of the walls is still increasing when the cell growth and division have stopped. 相似文献
109.
Gerd Joachim Dörrscheidt 《Biological cybernetics》1969,6(3):81-96
Summary From the communication engineers point of view the paper deals with networks consisting of linear filters and a special sort of controlled statistical pulse generators (SIG). The SIG responds to an analog signal with a sequence of Dirac impulses, where the probability for an output impulse at a given time depends on the instantaneous value of the input signal only. In connection with linear filters, however, systems can be realized in which the whole past of the input determines the statistical structure of the output. Therefore systems consisting of linear filters and SIGs (SIG networks) become interesting as models of biological systems, because in biological information processing transformations from analog signals into pulse trains occur very often. An example concerning the application of SIG systems in behavioural sciences will be discussed in a subsequent paper. In the present paper a theoretical analysis of the SIG and SIG networks is carried out by means of Statistical Communication Theory and Theory of Stochastic Processes. It is shown that under certain conditions very complex SIG networks can be treated with Correlation Theory. For one case not satisfying these conditions a solution on the base of Markoff processes is given.
Auszug aus einer von der Fakultät für Maschinenwesen und Elektrotechnik der Technischen Hochschule München genehmigten Dissertation.Herrn Prof. Dr.-Ing. H. Marko danke ich für das Interesse und die fördernde Kritik während des Entstehens der dieser Arbeit zugrundeliegenden Dissertation. Der Deutschen Forschungsgemeinschaft ist für die finanzielle Förderung der Untersuchungen zu danken. Die numerischen Berechnungen wurden auf der Rechenanlage TR4 des Leibniz-Rechenzentrums der Bayerischen Akademie der Wissenschaften durchgeführt. 相似文献
Auszug aus einer von der Fakultät für Maschinenwesen und Elektrotechnik der Technischen Hochschule München genehmigten Dissertation.Herrn Prof. Dr.-Ing. H. Marko danke ich für das Interesse und die fördernde Kritik während des Entstehens der dieser Arbeit zugrundeliegenden Dissertation. Der Deutschen Forschungsgemeinschaft ist für die finanzielle Förderung der Untersuchungen zu danken. Die numerischen Berechnungen wurden auf der Rechenanlage TR4 des Leibniz-Rechenzentrums der Bayerischen Akademie der Wissenschaften durchgeführt. 相似文献
110.
Gerhard Jörgensen 《Human genetics》1969,7(1):51-75
Zusammenfassung Ausgehend von 45 Probanden mit angeborenen organischen subvalvulären Aortenstenosen wurden Familienuntersuchungen durchgeführt. 29 Probanden hatten eine einfache (isolierte) Subaortenstenose (Tabelle 1), 16 weitere einen mit zusätzlichen Herzdefekten wie angeborener valvulärer Aortenstenose (n=3), Ductus arteriosus persistens (n=7), Aortenisthmusstenose (n=5) und Ventrikelseptumdefekt (n=2) kombinierten Typ (Tabelle 2 u. 3).Die Häufigkeit der angeborenen organischen Subaortenstenose liegt wahrscheinlich zwischen 0,0065% und 0,0162%.Das Geschlechtsverhältnis beträgt bei Zusammenfassung der eigenen Fälle mit Literaturbeobachtungen 2 :1 (Tabelle 3 u. 4).In den Familien der 45 Probanden wurden alle lebenden Eltern, Geschwister sowie Kinder, z. T. auch Großeltern und weitere Verwandte untersucht. In 11 Fällen famden sich in den Sippen weitere Angehörige mit angeborenen Herzfehlern (Tabelle 1 u. 2). In der Geschwisterschaft von Kranken beträgt die nach dem Maximum-likelihood-Verfahren errechnete Erkrankungswahrscheinlichkeit p=0,0361±0,00205 (k=0,rmin=1). Die Erkrankungswahrscheinlichkeit der Eltern, errechnet nach der Weinbergschen Probandenmethode, beträgt 3,3±1,9% (Tabelle 6).Ein Proband hat einen eineiigen, nicht betroffenen Zwillingsbruder.Das Durchschnittsalter der Väter der Probanden beträgt 30,6 Jahre, das der Mütter 28,6 Jahre und entspricht dem der Kontrollgruppe (Tabelle 7).Die Prüfung der Geburtenordnung nach dem Haldane-Smith-Verfahren ergab keine signifikante Differenz zwischen Beobachtung und Erwartung (Tabelle 8).Genetisch liegt den angeborenen organischen Subaortenstenosen vermutlich ein multifaktorielles genetisches System mit additiver Polygenie und Schwellenwerteffekt zugrunde.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献
Genetic investigations in congential organic subvalvular aortic stenosis
Summary Genetic investigations have been carried out on 45 propositi with congenital organic subvalvular aortic stenosis. From these, 29 had an isolated subvalvular aortic stenosis (see Table 1), 16 a type combined with other cardiac defects as valvular aortic stenosis (n=3), patent ductus arteriosus (n=7), coarctation of the aorta (n=5), and ventricular septal defect (n=2) (see Table 2 and 3).The incidence of this heart defect among all live births is probably 0.0065%–0.0162%.According to our own observations as well as to the literature the sex ratio of patients with organic subvalvular aortic stenosis is 2 :1 (see Table 3).In the families of the 45 propositi were examined all living parents, siblings and infants, in some cases also grand-parents and other family members. In all of them 11 relatives were affected with similar or-rarely-dissimilar congenital heart diseases (see Table 1 and 2). Using the maximum-likelihood-method, the risk of siblings to be affected is calculated as beeing p (k=0,rmin=1). Using the Weinberg method the probability of parents to be affected is 3.3±1,9% (see Table 6).One index patient had a monozygotic co-twin who is not affected.The average age of the fathers is 30.6 years and of the mothers 28.6 years (see Table 7). There is no statistical difference between parental age and that of the control sample.The birth-order effect was examined in our 45 patients (see Table 8) by the Haldane-Smith-method. There is no difference between observation and expectation.The hypothesis of a multifactorial genetic background is supposed as mode of inheritance of congenital organic subvalvular aortic stenosis.
Mit Unterstützung durch die Deutsche Forschungsgemeinschaft. 相似文献