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651.
Summary 4-Isothiocyanato-4-nitrodiphenylamine possessed anthelmintic activity againstNippostrongylus dubius andHymenolepis nana in mice andH. diminuta in rats as determined by both egg counts and recovery of parasites at autopsy. No activity was detected against the cestode,Spirometra mansonoides, in cats.This investigation was supported in part by grants AI-10512 and AI-09483 from the National Institutes of Health. The authors are indebted to Dr P.P. Weinstein for providing animals infected withSpirometra mansonoides.  相似文献   
652.
Summary Roots ofVicia faba L. immersed in a buffer solution were found to release esterases into the environment. The substrate -naphthylacetate was taken up by the roots and degraded, the hydrolysis products being released back into the surrounding medium.  相似文献   
653.
Summary Furocoumarin photosensitization induces -prophage from lysogenicEscherichia coli cells; this effect is clearly due to the photoreaction that furocoumarins give with DNA, and it appears connected with the formation of monoadducts rather than of diadducts (cross-links).Acknowledgments. The authors wish to express their thanks to Dr L. Conventi, Microbiology Institute of Padua University, for generously donating theE. coli strains used in this work.  相似文献   
654.
Summary In a group of 5 women taking oral contraceptives, the concentration of polymorphonuclear leucocytes along the gingival margin and the activities of cathepsin D, -glucuronidase and elastase were found to increase significantly during the intermenstrual phases.Supported by grant 3.604.075 of the Swiss National Fund for scientific Research. The authors thank Dr M. Baggiolini and Prof. A. Linder for the helpful advices.  相似文献   
655.
Day 25 after insemination is a date of peculiar importance in the maturation of several organs in the Rabbit fetus. From day 25 onward the fetal liver stores increasing amounts of glycogen and the lung stores increasing amounts of lecithins, concomitant with sudden rise in the activity of lung phosphatidic-acid phosphohydrolase. Earlier studies on decapitated fetuses established that glycogen storage in the liver is dependent on a dual hormonal control, comprising a pituitary hormone like growth hormone or prolactin (some placental hormones share the same activity) and corticosteroids (Jost, 1961). Since the variations in endogenous corticosteroids do not seem to herald these liver or lung changes (Mulay et al., 1973), a study was made of growth hormone. Plasma immunoreactive growth hormone--determined with a heterologous Rat system (Kervran et al., 1976)--increases eightfold between days 23 and 25. During the same time plasma prolactin does not change according to McNeily and Friesen, 1978, and to unpublished data obtained with Dr McNeilly. In preliminary assays, Rat growth hormone was seen to increase phosphorylase "a" activity in the lung of 18.5 day-old Rat fetuses, thus anticipating normal development. We suggest that growth hormone plays a role in initiating liver and lung maturation.  相似文献   
656.
Summary Synthetic 3-methylcyclohex-3-en-1-one, or 3,3-MCH, decreased by 77% the flight aggregation ofDendroctonus pseudotsugae (Scolytidae) to sticky traps containing attractant (frontalin, -pinene, and resin). However, windthrown trees were protected by 3,3-MCH much less than is known to occur with the isomer 3,2-MCH.This research was supported in part by NSF grants BMS 72-02522 and DEB 77-11361 and the O.S.U. School of Forestry. We thank the administration of the Siuslaw National Forest for study sites, and Dr L.M. Libbey for GC/MS of 3,3-MCH. Oregon State University Ag. Exp. Sta. Tech. Paper No. 4313.  相似文献   
657.
Summary Microelectrophoretic administration of D--aminoadipate reversibly reduced excitatory responses of cat dorsal horn neurones evoked by iontophoretic glutamate and non-noxious peripheral stimuli but did not influence similar responses evoked by noxious peripheral stimuli or iontophoretic substance P.  相似文献   
658.
Summary The active calcium transport along the small intestine of adult rat was shown to exhibit daily rhythmic variations of considerable amplitude. Both the light-dark cycle and the time of food presentation acted as synchronizers of the rhythm observed.This work has been supported by Polish Academy of Sciences within the project MR II.1.1.6.  相似文献   
659.
    
Summary InTambourissa religiosa (Monimiaceae), the flowers are pollinated at a hyperstigma formed by the mouth of the floral cup, and not at the carpels. This is an extraordinary feature in angiosperms.I thank Professor Dr W. Rauh, Institut für Systematische Botanik und Pflanzengeographie der Universität Heidelberg, for providing material from his green house collection (W. Rauh, No. M 138, coll. 1959) and Dr Christa Güssefeld-Schneider for fixing pollinated flowers.  相似文献   
660.
J R Martinez  O H Petersen 《Experientia》1979,35(10):1343-1345
Using an automated system for the analysis of amylase, the release of this enzyme was compared in superfused parotid gland segments from control and reserpine treated rats. Stimulant-evoked amylase release was delayed and of smaller magnitude in the glands of the treated animals and a reduction of the transmembrane K+ gradient caused a smaller and short lasting reduction in Ach-evoked release of amylase in the glands from these animals.  相似文献   
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