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961.
(E,Z)-2,13-octadecadien-1-ol acetate and (Z)-13-octadecen-1-ol acetate have been identified from the ovipositor extracts of the currant borer, Synanthedon tipuliformis (Clerck), by capillary GC, and the structures were verified by GC-MS. The diene/monoene ratio in the extract was found to be 93:7. Mixtures of these two compounds as well as the diene alone attracted conspecific males in the field.
Zusammenfassung (E,Z)-2,13-Octadecadienylacetat und (Z)-13-Octadecenylacetat wurden in Ovipositor-Extrakten des Johannisbeerglasflüglers Synanthedon tipuliformis kapillar-gaschromatographisch nachgewiesen. Die Strukturen wurden mittels Gaschromatographisch-Massenspektrometrie bestätigt. Das Verhältnis Dien/Monoen im Extrakt betrug 93:7. Mischungen der beiden Komponenten wie auch (E,Z)-2,13-Octadecadienylacetat allein lockten im Freiland Männchen dieser Glasflüglerart an.
  相似文献   
962.
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964.
Murine monoclonal antibodies (mAbs) were obtained against the outer-surface-protein OspA and OspB and against the 41-kDa flagellar antigen of Borrelia burgdorferi. The specificity of mAb was determined by the Western blotting technique and the surface association of the antigens was inferred by immunofluorescence of living bacteria. In an in vitro assay in the presence of complement, two mAbs reactive with the Ospa were able to kill borreliae, whereas several mAbs reactive with the OspA as well as with the 41-kDa flagellar protein were not.  相似文献   
965.
A Tsukise  W Meyer  R Schwarz 《Acta anatomica》1983,115(2):141-150
The histochemistry of carbohydrates has been studied in the skin of the pig snout with selected methods of light microscopy including peroxidase-labelled lectin-diaminobenzidine (PO-LT-DAB) procedures. In the snout skin the dark secretory cells and the luminal secretion of the eccrine glands contained considerable amounts of neutral glycoproteins, but only a very small amount of acidic ones. It was possible to demonstrate glycogen in the secretory cells of these glands. The other skin structures of the snout also showed positive reactions for complex carbohydrates. Most remarkable were stronger reactions of intercellular substances among the spinosum cells, particularly following the PO-LT-DAB procedures, which demonstrated such saccharide residues as beta-D-galactose and N-acetyl-D-glucosamine.  相似文献   
966.
Summary 1. Subcutaneous inoculation into the forelegs of hamsters withC. neoformans following trauma as well as subcutaneous inoculation into the abdominal wall led to infection with dissemination.2. Active skin lesions persisted during the 39 days of the experiment without regression of skin lesions.3. Involvement of lymph nodes was observed in (a few) animals infected with strains 220 and 216 only.4. In addition to the virulence of the strain, the dose of the organisms also affected the degree of infection in the tissues.5 Intratesticular inoculation led to infection with faster and more severe dissemination.6. Schaumann bodies were observed in skin lesions.7. Cortisone accelerated the course of infection.8. Primary skin infection with subsequent I.P. challenge produced a partial protection insofar as the hematogenous spread was concerned.  相似文献   
967.
Zusammenfassung Es wurde eine Reihe von Entwicklungsstadien der menschlichen Cornea und Sklera untersucht. Dabei zeigte sich, daß die Corneafibrillen aller Entwicklungsstufen ein gleiches Verhalten aufweisen. Der Hauptwert der Fibrillendicke liegt bei 30–35 m, die Schwankungsbreite ist gering. Die unperiodische Außenversilberung bleibt während des ganzen Lebens erhalten. Im Gegensatz zu den Corneafibrillen differenzieren sich die Sklerafibrillen während der Entwicklung. Es wurden die einzelnen Differenzierungsstufen beschrieben und tabellarisch zusammengefaßt. Endpunkt der Fibrillendifferenzierung ist die dicke, innenversilberte Kollagenfibrille. Bei zwei pathologisch veränderten Hornhäuten wurde ebenfalls eine Differenzierung der Fibrillen in Richtung auf das reife Kollagen festgestellt. Es war möglich, diese Fibrillen jeweils einer bestimmten Entwicklungsstufe der Sklerafibrillen zuzuordnen. Die Konsequenzen, die sich aus diesen Befunden für das Problem der Durchsichtigkeit der Cornea und für die Transplantation ergeben, werden diskutiert.  相似文献   
968.
Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system (CNS). Neither the antigenic target(s) nor the cell population(s) responsible for CNS tissue destruction in MS have been fully defined. The objective of this study was to simultaneously determine the antigen (Ag)-specificity and phenotype of un-manipulated intrathecal CD4+ and CD8+ T cells of patients with relapsing-remitting and progressive MS compared to subjects with other inflammatory neurological diseases. We applied a novel Ag-recognition assay based on co-cultures of freshly obtained cerebrospinal fluid T cells and autologous dendritic cells pre-loaded with complex candidate Ag''s. We observed comparably low T cell responses to complex auto-Ag''s including human myelin, brain homogenate, and cell lysates of apoptotically modified oligodendroglial and neuronal cells in all cohorts and both compartments. Conversely, we detected a strong intrathecal enrichment of Epstein-Barr virus- and human herpes virus 6-specific (but not cytomegalovirus-specific) reactivities of the Th1-phenotype throughout all patients. Qualitatively, the intrathecal enrichment of herpes virus reactivities was more pronounced in MS patients. This enrichment was completely reversed by long-term treatment with the IL-2 modulating antibody daclizumab, which strongly inhibits MS disease activity. Finally, we observed a striking discrepancy between diminished intrathecal T cell proliferation and enhanced cytokine production of herpes virus-specific T cells among progressive MS patients, consistent with the phenotype of terminally differentiated cells. The data suggest that intrathecal administration of novel therapeutic agents targeting immune cells outside of the proliferation cycle may be necessary to effectively eliminate intrathecal inflammation in progressive MS.  相似文献   
969.
970.
Abstract

Elicitins, produced by most of the phytopathogenic fungi of the genus Phytophthora, provoke in the tobacco plant both remote leaf necrosis and the induction of a resistance against subsequent attack by various micro-organisms. The crystal structure of b-cryptogein (CRY), secreted by Phytophthora cryptogea, was previously reported as well as the first structure of a SCP/sterol complex, the ergosterol-complexed, mutated CRY (K13H). In K13H, the ergosterol molecule is encapsulated in a large internal hydrophobic cavity which is not present in CRY. This binding induces a minor conformational change in the protein structure. Molecular dynamics studies were undertaken to precise the structural behaviour of CRY and K13H with respect to the complexation of the ergosterol.

Although it is not possible to simulate the entrance of the ergosterol in the protein, we assume that capture and release of the ligand possibly both occur following the same path. Our results show that, in the complex K13H, the ergosterol molecule is pushed towards the residue 13 which play a key role in the necrotic activity of the protein. It is likely that the polarity of residue 13, favouring the binding of the hydroxy l of the ligand, would be involved in the recognition of the sterol and in an optimisation of its orientation. Thus, in a first step, the molecule of ergosterol would be rotated around itself to a position which makes possible, in a second step, its translation to the internal cavity, as a key in a keyhole.  相似文献   
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