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Bernhard Werner 《Helgoland Marine Research》1966,13(4):317-347
The scyphopolypStephanoscyphus Allman 1874 represents the polyp generation of the scyphomedusan order Coronatae. Though this polyp has been known for more than a hundred years its general morphology, systematics, and evolution have been inadequately described. Participating in the International Indian Ocean Expedition, 1964 to 1965, on board of the German research vessel “Meteor”, the author was able to collect a sufficient supply of livingStephanoscyphus off the coasts of South Arabia and East Africa. For the first time, it was possible to rear these polyps in laboratory cultures. A thorough investigation of morphology, developmental history and behaviour based on longterm observations of the living polyps gave clear indications thatStephanoscyphus directly descended from the fossil group of Conulata, the scyphozoan nature of which has been affirmed byKiderlen (1937) andKnight (1937). The main feature whichStephanoscyphus has in common with the Conulata is the possession of a periderm tube. The characteristics found in a detailed investigation of the periderm tube conform well with those found in the periderm of the Conulata except for the closure of the aperture by triangular flaps which are absent inStephanoscyphus. The soft body contains primitive features as well. Hence it must be concluded finally that the type of organization which the fossil ancestors exhibited has survived inStephanoscyphus and that the Coronatae represent the most basic group of all living Scyphozoa. On the other hand, the results give strong support for the scyphozoan nature of the Conulata, the organization and life history of which have been elucidated by the observations of the living representatives ofStephanoscyphus. 相似文献
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The fatty acid composition of ER, Golgi and peribacteroid membrane (PBM) from root nodules formed on Glycine max after infection with different strains of Bradyrhizobium japonicum has been analysed by gas chromatography. In each plant-microsymbiont combination the fatty acid composition (FAC) of the PBM is distinct from ER and Golgi. The similarity between ER and PBM fatty acid composition is significantly stronger than between Golgi and PBM. In addition the fatty acid composition of all membrane systems in nodules is affected by the microsymbiont strain. A comparison of four strains of Bradyrhizobium japonicum grown in agar surface culture and isolated as the symbiotic bacteroids reveals a decrease in oleic acid during bacteroid differentiation. 相似文献
146.
Ultrasensitive bioluminescence immunoassays for the determination of peptides and proteins (illustrated with human urinary kallikrein, bradykinin and the determination of human urinary kallikrein antibody titres) have been developed. The usable ranges of the standard curves are from 5 pg to 5000 pg per litre. The relative intra-assay coefficients of variation of the tests were between 2% and 6%, and the inter-assay coefficients of variation between 4% and 12%. 相似文献
147.
Jürgen Beckmann Armin Mehlich Werner Schröder Herbert R. Wenzel Harald Tschesche 《The protein journal》1989,8(1):101-113
The semisynthesis of homologues of aprotinin, the bovine pancreatic trypsin inhibitor, is described. The P1 lysine15 residue was replaced by two methods. The first procedure, which consisted of two enzymatic steps for the incorporation of other amino acids has previously been described. The second approach consisted of six steps of both enzymatic and chemical nature. The modified inhibitor, in which the lysine15-alanine16 peptide bond is hydrolyzed, was used as the starting material. All carboxyl groups of the modified inhibitor were esterified with methanol; the lysine15 methylester group was then selectively hydrolyzed. Afterward, lysine15 itself was split off. Arginine, glutamic acid, methionine, andl-2-aminohexanoic acid (norleucine, Nle) were incorporated using water-soluble carbodiimide combined with an acylation catalyst. The methylester group was used to prevent polymerization. The reactive-site peptide bonds were resynthesized using either chymotrypsin or trypsin. 相似文献
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Immunohistochemical absence of adrenergic neurons in the dorsal part of the solitary tract nucleus in sudden infant death 总被引:1,自引:0,他引:1
F Chigr M Najimi D Jordan L Denoroy J Pearson M Tommasi R Gilly N Kopp 《Comptes rendus de l'Académie des sciences. Série III, Sciences de la vie》1989,309(12):543-549
The immunohistochemical distribution of TH and PNMT containing neuronal elements was investigated utilizing peroxidase anti-peroxidase methods in newborn control and sudden infant death syndrome (SIDS) brainstems. The TH immunoreactive neurons, within the medulla oblongata, displayed a similar distribution in both control and SIDS tissue. However, PNMT immunoreactive neurons seen in the dorsal part of the nucleus of tractus solitarius in control tissue were not observed in SIDS tissue. This alteration of adrenergic neurons in the dorsal part of NTS (region reported to be implicated in the control of blood pressure and respiration) could explain the cardiorespiratory disorders in SIDS. 相似文献