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941.
Summary An inbred strain (Istanbul) of guppies was divided into two substrains, one of which was maintained and bred in seawater. The offspring of irradiated animals of both substrains (1000 R X-rays to spermatogonia and oogonia of neonatal fish) were tested in a new gruppy male courtship activity test and compared with control groups. The postirradiation response in the seawater substrain was more intense than in the freshwater substrain.Dedicated to Prof.Dr.Dr.h.c.mult. Curt Kosswig on the occasion of his 75th birthday  相似文献   
942.
943.
For certain environments, the Darwinian model allows unique prediction of a function that any surviving system adapted to such an environment has to perform. This is the case for those environments that determine a “survival functional” of position in space-time of known shape. Purely temporal survival functionals can be distinguished from spatial and mixed ones. In each case, there exists an optimum path in combined physical and (reduced) metabolic space. Dependent on the admissible error, approximate solutions of different complexity are sufficient. All solutions possess an afferent, a central, and an efferent part. Within this general frame, specific, “probably simplest”, solutions are proposed for adaptive chemotaxis, insect locomotion, lower vertebrates locomotion, higher vertebrates locomotion, chronobiological systems, and immune systems, respectively—or rather, for the underlying functionals. Presented at the Society for Mathematical Biology Meeting, University of Pennsylvania, Philadelphia, August 19–21, 1976.  相似文献   
944.
Oxidation of ferrocytochrome c by molecular oxygen catalysed by cytochrome c oxidase (cytochrome aa3) is coupled to translocation of H+ ions across the mitochondrial membrane. The proton pump is an intrinsic property of the cytochrome c oxidase complex as revealed by studies with phospholipid vesicles inlayed with the purified enzyme. As the conformation of cytochrome aa3 is specifically sensitive to the electrochemical proton gradient across the mitochondrial membrane, it is likely that redox energy is primarily conserved as a conformational “strain” in the cytochrome aa3 complex, followed by relaxation linked to proton translocation. Similar principles of energy conservation and transduction may apply on other respiratory chain complexes and on mitochondrial ATP synthase.  相似文献   
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946.
947.
Target cells for the activity of a synthetic adjuvant: muramyl dipeptide.   总被引:4,自引:0,他引:4  
Muramyl dipeptide (MDP), a synthetic adjuvant, increased the primary response of CBA mice to sheep red blood cells (SRBC). In reconstituted irradiated recipients, cooperation between T and B lymphocytes was required for the expression of adjuvant activity and MDP increased the efficiency of SRBC-educated T cells. The role of T-derived lymphocytes in mediating the MDP adjuvant activity was also demonstrated in irradiated mice and in mice reconstituted with various splenic cellular types of donors which had received SRBC and MDP 24 hr earlier. In our experiments, the macrophage did not seem to be involved, since MDP did not increase the phagocytic capacity of peritoneal exudate cells and MDP- and SRBC-pretreated macrophages had no increased ability to induce an anti-SRBC immune response. These results demonstrate the importance of T lymphocytes as mediators of the adjuvant activity of MDP.  相似文献   
948.
Summary A heme-nonapeptide (H-9-P)1, applicable to electron microscopic cytochemistry via peroxidase-like activity, was prepared by passing horse heart cytochrome c through a column with Sepharose and covalently attached trypsin. After purification by column chromatography (Sephadex G50 Superfine, Biogel P-2) a maximal yield of 50% and purity of >99% was achieved. A concise schedule allows for inexpensive preparation of H-9-P with standard laboratory equipment. H-9-P has the following properties: Its structure is (14) Cys-Ala-Gln-Cys-His-Thr-Val-Glu-Lys (22) with heme attached to Cys (14) and (17). MW=1630, pI=4.95, E(max) pH 7 = 397.5 nm, 22 °C, pH 7 397.5 nm = 1.11 × 105 [Liter/Mole x cm]. With the use of a diaminobenzidine-H2O2-medium — as applied for cytochemistry — we determined spectrophotometrically a pHopt=12.5 and an apparent K5 = 3.14 × 10– 3 [M]. Glutardialdehyde leads to considerable de-activation and, according to SDS-polyacrylamide-gel-electrophoresis, to diffuse crosslinking accompanied by a shift of the active pH-region towards neutral pH values. An attempt was made to optimize the cytochemical assay. The peroxidase-like activity of H-9-P is well comparable to that of other heme-tracers; only horseradish peroxidase has a higher turnover number. When injected to mice or added to cell suspensions, even high concentrations of H-9-P did not entail any signs of toxicity.Abbreviations AAA amino acid analysis - AHC ammoniumhydrogencarbonate - BSA bovine serum albumin - Cyt c cytochrome c - DAB 5,3-diaminobenzidine - GA glutardialdehyde - H-8-P heme-octapeptide - H-9-P heme-nonapeptide - H-11-P heme-undecapeptide - HR-POX horseradish peroxidase - MW molecular weight - PAGE polyacrylamid-gel-electrophoresis - pI isoelectric point - SDS sodiumdodecylsulphate - SG-TLC silicagel-thin-layer-chromatography This work was supported by the Österreichische Forschungsfonds  相似文献   
949.
Zusammenfassung Kernpolyeder vonMamestra brassicae (L.) wurden auf Nebenwirkungen an zwei Entomophagen-Arten in der Basis- Konzentration (LC100 für den natürlichen Wirt) sowie der 5- und 10 fachen Konzentration geprüft. Schadwirkung durch Kontakt mit frisch angetrocknetem Belag bzw. durch Verfüttern eines kontaminierten N?hrsubstrates auf den EiparasitenTrichogramma cacoeciae Marchal konnte nicht nachgewiesen werden. Ebenso wurde die Entwicklung vonT. cacoeciae in parasitierten Wirtseiern durch eine Tauchbehandlung mit der Kernpolyeder-Suspension in verschiedenen Intervallen nach der Parasitierung nicht gest?rt. Im Wahl- und Nichtwahlversuch konnte keine Repellentwirkung von Wirtseiern festgstellt werden, die in eine Kernpolyeder-Suspension getaucht worden waren. Die r?uberischen Larven vonChrysopa carnea Steph. waren gegenüber der 10fachen Basiskonzentration bei direktem Bespritzen der Larven, Kontakt mit einem frisch angetrockneten sprit zbelag sowie bei peroraler Aufnahme unempfindlich, wie die Frassleistung der Larven, die Fekundit?t der Imagines sowie die Schlüpfrate der Eier zeigte. Bei praktischen Eins?tzen von Kernpolyeder-Pr?paraten zur Bek?mpfung der Kohleule sind im Gegensatz zu den üblichen Anwendungen von Phosphors?ureestern keine direkten Nebenwirkungen auf die untersuchten Nutzinsekten zu erwarten.
Summary The side effect of a water suspension of polyhedral inclusion bodies of nuclnear polyhedrosis virus (NPV) fromMamestra brassicae (L.) in a concentration of 1-, 5-, and 10-fold of the LC100 for the natural host was tested on two beneficial insects. No reduction in the parasitization capacity ofTrichogramma cacoeciae Marchal (Hym.: Trichogrammatidae) was recorded when adults were exposed to a fresh dry film, or fed on contaminated honey-agar. The development of the parasite inSitotroga cerealella Oliv. host eggs was not affected when these were dipped in a suspension of the NPV at different time intervals after parasitization. In additional tests, it was shown that deposit of the NPV suspension had no repellent effect onTrichogramma. The feeding capacity of the predatory larve ofChrysopa carnea Steph., fecundity of the adults as well as viability of the eggs were not affected when the larvae were directly sprayed with the highest tested concentration of the suspension, exposed to fresh dry film or fed on contaminated diet. These experiments indicate that, in contrast to the use of the conventional organophosphorus insecticides, no hazard to the tested beneficial insects should be expected when the preparation of the polyhedral inclusion bodies will be used in the field.


Nr. 2 der Serie: Wirkung von Insektenpathogenen auf Entomophagen. Als Nr. 1 gilt:S. Hassan & A. Krieg: über die schonende Wirkung vonBacillus thuringiensis-Pr?paraten auf den ParasitenTrichogramma cacoeciae (Hym.: Trichogrammatidae). — Z. Pfl. Krankh. Pfl. Schutz, 82, 515–521, 1975.  相似文献   
950.
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