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321.
Summary Complete removal of villous as well as upper-crypt epithelium was achieved in vivo by vibration of an intestinal segment using tetraphenylboron sodium (TPB) as a disassociation agent.Acknowledgments. The authors thank Hicol Industrieterrein De Bosschen for supplying TPB. Research was supported by MR-II 1.3.14.p.2 grant.  相似文献   
322.
Summary Methanol extracts of the skin of the South African amphibians belonging to the genusHeleophryne (H. purcelli purcelli, H. purcelli depressa, H. purcelli orientalis, H. natalensis) contain large amounts (20–500 g/g fresh tissue) of Hyp3-bradykinin.Supported by grants from the Consiglio Nazionale delle Ricerche, Italy, and from the Ministry of Education, Japan.  相似文献   
323.
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   
324.
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 During the same time plasma prolactin does not change according to McNeily and Friesen, 1978, and to unpublished data obtained with Dr McNeilly.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   
325.
In 10 sibships of haemophilic A patients, every one including 1 haemophilic brother with an antibody to factor VIII and 1 haemophilic brother without antibody, pattern of HLA segregation was analysed. All sibships were HLA haploidentical or different and not HLA identical. This fact suggested a linkage between the major histocompatibility complex and an "Ir" gene to factor VIII.  相似文献   
326.
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   
327.
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   
328.
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   
329.
Effects were examined of atropine, diazepam, pethidene, promethazine, scopolamine, omnopon and papaverine on basal and noradrenaline-stimulated lipolysis in rat isolated fat cells and on rat adipose tissue cyclic AMP phosphodiesterase activity. Papaverine at high concentration (1 mM) inhibited both basal and hormone-stimulated lipolysis, whereas diazepam enhanced basal lipolysis. At a 'clinical dose', omnopon increased both basal and noradrenaline-stimulated lipolysis. Adipose tissue cAMP phosphodiesterase activity was strongly inhibited by 1 mM diazepam, papaverine, promethazine and omnopon (280 microgram ml-1). Lack of enhancement of lipolysis by the established cAMP phosphodiesterase antagonist papaverine, is compatible with simultaneous inhibition also of adipose adenyl cyclase. Diazepam-stimulated lipolysis is compatible with its phosphodiesterase inhibitory activity. It is proposed that papaverine-containing omnopon may offer some survival advantages during surgical stress by facilitating a caloric supply.  相似文献   
330.
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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