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461.
Summary Contrary to Srdi and Gloor's report, we find crystal cells (cc) in the lymph glands ofD. melanogaster larvae; the size and number of inclusions in the cc cannot be used to distinguish the 2 sibling species,D. melanogaster andD. simulans; cc in the hemocoel are not phagocytic cells; the surface properties of the lamellocytes are consistent with their derivation from plasmatocytes and not cc.Supported by grant No. CA16619 awarded by the National Cancer Institute, DHEW, USPHS.  相似文献   
462.
Summary The relaxant effects of isoprenaline on rabbit isolated renal artery and aorta were compared. The results suggest that although isoprenaline acts on -adrenoceptors in the aorta it stimulates dopamine receptors in the renal artery.  相似文献   
463.
Summary Furocaulerpin, an acetylenic sesquiterpenoid possessing a furan ring, has been isolated from the marine algaCaulerpa prolifera, and its stereostructure elucidated mainly on the basis of physico-chemical data.This work was carried out in the frame work of the Progetto Finalizzato per l'Oceanografia e i Fondi Marini, CNR, Rome. Thanks are due to the Centro di Metodologie Chimico-Fisiche of the University of Naples (Mr I. Giudicianni) for the determination of PMR-spectra.  相似文献   
464.
Summary The concentrations of testosterone (T) and 5-dihydrotestosterone were measured in fluid collected from the rete testis of immature and adult rats. The results indicate that adult levels of T are attained in the seminiferous tubules much earlier than in the peripheral circulation.This work was performed at the Worcester Foundation for Experimental Biology, Shrewsbury, Massachusetts, USA and supported by the National Institutes of Health through grants HD12641 and HD12642. We thank Dr B.V. Caldwell for antiserum to testosterone.  相似文献   
465.
Summary Isonicotinic acid hydrazide (isoniazid) was shown to react readily with 17-ethinyl-17-hydroxyestr-4-en-3-one (norethindrone) to form the isonicotinyl hydrazone of the steroid under conditions likely to exist in the stomach. The hydrazone was detected in guinea-pig, but not rat, plasma following its oral administration. Rat liver tissue metabolized the compound more rapidly than guinea-pig liver in vitro which probably accounts for the failure to detect the hydrazone in rat plasma.  相似文献   
466.
Summary After 3 weeks of continuous ethanol intoxication by inhalation, the maximal number and affinity of the -and -receptors of rat heart were unchanged. These data indicate that adrenergic receptor disturbances are not involved in the mechanism of chronic ethanol-induced triglyceride deposition in the heart.Acknowledgments. This work was supported by grants from the Institut National de la Santé et de la Recherche Médicale. We wish to thank Mr M. Clément for skilled technical assistance in performing chronic ethanol inhalation treatments.  相似文献   
467.
Summary Protein from resting or phytohemagglutinin-stimulated human peripheral blood T-lymphocytes, pulse-labeled in vitro for 1 h with3H-leucine, had a half-life of 30 h.  相似文献   
468.
Summary DNA-containing areas in various phages (T4, , T7 and 29) could be observed at the light microscopic level using ethidium bromide epi-fluorescent microscopy. The fluorescent intensity per phage was in linear proportion to the DNA content in each phage.Acknowledgements. This work was supported in part by the grant No. 521708 and No. 511212 from the Japan Ministry of Education, Science and Culture.  相似文献   
469.
Summary In the sandal plant affected by spike disease, caused by mycoplasma-like organisms, the changes occurring in the 5-and 3-nucleotidase activities were studied and their possible significance discussed.  相似文献   
470.
Summary A novel sesquiterpene lactone, 9--hydroxyparthenolide (1) was isolated from a chloroform extract ofAnvillea garcini that was collected in Iran. The structure of1 was assigned on the basis of high field NMR decoupling experiments and other spectroscopic evidence. This -methylene lactone has shown significant activity in both the 9KB cell culture and P388 mouse leukemia test systems.The authors acknowledge the support of contract No. N01-CM-97296 from the National Cancer Institute and the use of the Purdue University Biochemical Magnetic Resonance Laboratory (NIH grant No. RR01077). This is paper 16 in the series Potential Antitumor Agents.  相似文献   
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