任意波形合成系统硬件设计

提出并分析了任意波形合成系统（ＡＷＳ）──一种高度智能化的计算机仪器的几种典型结构及其特点，着重讨论了ＰＣ总线式任意波形合成系统的系统组成及各部分硬件电路设计的关键技术     

High frequency of unequal recombination in pseudoautosomal region shown by proviral insertion in transgenic mouse

The mammalian X and Y chromosomes, in contrast to the autosomes, pair during male meiosis only near the telomeres. Alleles localized in this region can undergo reciprocal exchange during meiosis. Because such sequences do not show strict sex-linked inheritance, they have been termed pseudoautosomal. In man, several DNA sequences have been described which show pseudoautosomal transmission and which are localized in the pairing region at the ends of the short arms of both the X and Y chromosomes (refs 6-9, and D. Page, unpublished results). We now show that the transgenic mouse strain, Mov-15, contains a single Moloney murine leukaemia virus (M-MuLV) genome in its germline, and genetic evidence indicates that the provirus is integrated into the pseudoautosomal region of the sex chromosome. Proviral copies are lost or gained in 7% of male meioses in this strain, and mouse sequences flanking the provirus are tandemly repeated and highly variable. We conclude that unequal recombination events occur with high frequency in the pairing region, possibly because of the presence of repeated sequences.     

Bone marrow genotoxicity of N-methyl, N-nitrosourea (NMU): n-alkanols as sister chromatid exchange (SCE) anti-inducers

The in vivo SCE test was used to demonstrate significant inhibition of NMU bone marrow genotoxicity by pretreatment of Chinese hamsters with n-alkanols. Our findings exclude a loss of intracellular DNA alkylation potential through a competitive direct reaction of NMU with the weakly nucleophilic polar end of the n-alkanols, but not through methylations of nucleophilic membrane sites possibly liberated by structural modifications which the membrane-active amphiphilics induce.     

Der Einfluss des Urin-pH auf die Aktivität von Urinenzymen

Summary The relationship between the pH of urine and the measured activity of ULDH, UAP and UAA was investigated in vivo and in vitro. The activity of ULDH and UAP is only half as much, or less, in acid urine (pH 4.8–5.1) as it is in alkaline urine (pH 7.0–8.1). The UAA activity, however, does not change in the pH range measured. The isoenzymes ULDH 2–4, present in alkaline urine of normal adults, does not appear in acid urine.     

On the relative position of the centromere of chromosome 3 inDrosophila melanogaster

Zusammenfassung HomozygoteDrosophila-melanogaster-Weibchen, genetisch markiert mit scarlet (st), Kinked (Ki) und pink peach (P^p) wurden bestrahlt, um Compound-3-Chromosomen herzustellen. Es wurden ausschliesslich st/st- und P^p Ki/Ki(?) P^p-Compoundchromosomen gefunden. Dies zeigt, dass das Zentromer links der Markierung Kinked liegt.

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This work was supported by Schweizerischer Nationalfonds zur Förderung der wissenschaftlichen Forschung.     

Lettuce seedling growth: Antagonism between gibberellic acid and Niacin

Zusammenfassung Gibberellin und Niacin sind Antagonisten, Niacin hemmt das Wurzelwachstum vonLactuca sativa, während Gibberellin diese Wirkung teilweise aufhob.     

Depletion and repletion of noradrenaline in adrenergic nerves of the rat after decaborane treatment

Zusammenfassung Mit Hilfe der Fluoreszenz-Technik werden die Veränderungen in sympathischen Fasern der Ratteniris nach Noradrenalin-Depletion durch Boron-Hydrid Decarboran (Dopa-Dekarboxylase-Hemmer) analysiert.

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This work has been supported by grants from the Swedish Medical Research Council under project No. B70-14x-97-06B, B70-14x-711-05B and Knut and Alice Wallenberg Foundation.