Untersuchungen über den Wirkungsmechanismus von Procarbazin (Natulan®)

Summary The cytotoxic methylhydrazine derivative procarbazine or Natulan® has a marked influence on the synthesis of deoxyribonucleic acid in Ehrlich ascites carcinoma cells. The incorporation of³H-thymidine into DNA — measured by autoradiographic methods — is inhibited.     

Glial cells express N-CAM/D2-CAM-like polypeptides in vitro

The joining together of neurites to form fascicles and the growth of axons along glial surfaces during early development suggest that neurone-neurone and neurone-glial adhesion interactions are of considerable importance for defining nerve tracts. In vitro studies have indicated that adhesion between neurones involves a glycoprotein that has been independently studied under the names of N-CAM (for neural cell adhesion molecule), D2-CAM and BSP-2 (refs 10, 11). As N-CAM/D2-CAM appears to be a homophilic ligand that binds to N-CAM/D2-CAM polypeptide on adjacent cells, this glycoprotein is potentially important in adhesion interactions between any two N-CAM/D2-CAM-expressing cells. While it has been suggested that neurone-glial adhesion involves molecules other than N-CAM/D2-CAM, it is known that N-CAM/D2-CAM antigenic determinants are expressed by glial cells in vivo and that injection of anti-N-CAM antibodies into the eye-cup of chick embryos disrupts normal patterns of neuritic apposition to glial endfeet in the developing optic stalk. Do the molecules expressed by glia share restricted antigenic determinants, or binding domains, with N-CAM/D2-CAM, or are N-CAM/D2-CAM polypeptides expressed by glia? Here we present immunocytochemical evidence which suggests that all classes of macroglia express N-CAM/D2-CAM antigenic determinants on their surfaces and immunochemical analyses which indicate that the molecules expressed by purified astrocytes are closely similar, or identical, to at least some forms of N-CAM/D2-CAM obtained from whole brain or purified neurones. However, our results also suggest that different N-CAM/D2-CAM polypeptides may be separately expressed by neurones and astrocytes.     

Thermodynamics of the long range assembly of safranine T on molecular surfaces of nucleic acids

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Myocardial concentrations of high energy phosphates in normal mini-pigs and dogs

Zusammenfassung Die Gewebskonzentrationen an ATP, ADP, ATP+ADP, Kreatinphosphat, Kreatin und Kreatinphosphat + Kreatin sind unter vergleichbaren Bedingungen im linken Ventrikel von Mini-pig-Herzen kleiner als im Hundeherzen. Die Unterschiede in den Koeffizienten (ATP/ADP und Kreatinphosphat/Kreatin) dürfen narkosebedingt sein. Sämtliche Messgrössen sind nicht mit dem Entnahmeort der Biopsien (apikal, basal) korreliert.

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Supported by the Swiss National Science Foundation (Grant Nr. 3.484).     

Cytological investigations with a new class of cytotoxic agents: Methylhydrazine derivatives

Zusammenfassung Mittels cytologischer Untersuchungen wurde versucht, einen Einblick in den Wirkungsmechanismus der tumorhemmenden Methylhydrazinverbindungen zu gewinnen. 1-Methyl-2-benzyl-hydrazinphosphat bewirkt beim Ehrlich-Ascites-Carcinom der Maus einen Abfall des Mitoseindexes, eine Verschiebung des Mitosephasenindexes zugunsten der Metaphase sowie das Auftreten von Chromatidbrüchen. Diese Befunde werden diskutiert.     

Untersuchungen über die Genetik der Aposporie bei pseudogamen Potentillen

Summary It may be supposed that the somatic and generative apospory of the genusPotentilla is due to different factors and that these factors have a quantitative effect.     

西藏甲玛铜多金属矿含矿斑岩石英斑晶单个熔融包裹体的成分研究

研究甲玛铜多金属矿床岩浆结晶演化特点、岩浆热液过渡与矿化的关系。利用Linkam TS1500热台对甲玛矿床含矿斑岩石英斑晶中的熔融包裹体进行鉴定、均一温度测定,采用电子探针与同步辐射X射线荧光微探针对石英斑晶中的熔融包裹体进行常量元素及微量元素的测定,结果表明,含矿斑岩体形成温度为630~880℃。Na、Ca等元素易富集于岩浆挥发组分中,挥发组分饱和出溶形成高温、高盐度流体,成矿元素从最早的岩浆结晶分异阶段开始,强烈地选择性进入挥发性气相中进行迁移,出溶的挥发组分中具有成矿元素的初步富集。矿床在成因上与斑岩-夕卡岩成矿系统中的岩浆-热液成矿作用密切相关。