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151.
Summary Resting oxygen consumption of the vascularly isolated gracilis anticus muscle of the rat perfused by natural circulation via the femoral artery with diluted or undiluted blood depends on oxygen delivery (the product of flow rate and arterial oxygen concentration-DO2) only when DO2 falls below 16 l/min/g. 相似文献
152.
F. V. DeFeudis L. M. Orensanz Muñoz M. A. Vidal G. Corrochano M. Sanchez del Alamo 《Cellular and molecular life sciences : CMLS》1978,34(9):1169-1170
Summary High-affinity, Na+-independent binding of -alanine to a synaptosomal fraction of rat brain was potently inhibited by glycine and by some other -amino acids, but not by taurine or GABA. This binding mechanism, which was also sensitive to both bicuculline and strychnine, might involve synaptic receptors for both -alanine and glycine.This study was supported in part by Centro Ramón y Cajal and Fundacion Juan March. 相似文献
153.
Summary The secondary disease in PF1 strain combination depends upon the immune status of both partners. It is most clearly expressed if both donors and recipients are immunologically crippled by thymectomy and irradiation. Conspicuous reduction in the immune potential of parental parabionts induced by thymectomy and irradiation displayed their marked incidence of parabiotic death. 相似文献
154.
M. Schwab J. Haas S. Abdo M. R. Ahuja G. Kollinger A. Anders F. Anders 《Cellular and molecular life sciences : CMLS》1978,34(6):780-782
Summary Specific genotypes of the xiphophorine fish develop neoplasms following treatment with N-methyl-N-nitrosourea or X-rays. Several of these neoplasms can be related to the presence of specific chromosomes. The implications of these findings are discussed.Supported by Deutsche Forschungsgemeinschaft through Sonderforschungsbereich 103 Zellenergetik und Zelldifferenzierung, Marburg (projects C 9 and C 10), and by Justus-Liebig-Universität Giessen. We are indebted to Prof. K. Frese, Veterinär-Pathologisches Institut, Giessen and Dr H. D. Mennel, Pathologisches Institut, Freiburg, for their help in the classification of neoplasms. We furthermore thank K. Klinke for breeding the fish. Dedicated to Prof. C. Kosswig on the occasion of his 75th birthday.The paper contains parts of the dissertations of S. Abdo, J. Haas and G. Kollinger.supported by the Egypt ministry of education. 相似文献
155.
K. Nielsen J. Sheppard W. Holmes I. Tizard 《Cellular and molecular life sciences : CMLS》1978,34(1):118-119
Summary Rats infected withTrypanosoma lewisi or decomplemented by injection of cobra venom factor or complement activating factor of trypanosomes were found to be more susceptible to infection withSalmonella typhimurium. Decomplemented rats subsequently infected withT. lewisi developed higher blood parasitemia than did normalT. lewisi infected rats.This project is supported by the National Research Council of Canada grant A 0068 and a grant from the International Development Research Center. 相似文献
156.
N. Michajlovskij V. Štrbák O. Földes 《Cellular and molecular life sciences : CMLS》1978,34(3):409-410
Summary The administration of thiocyanate to rats caused a significant increase of serum free thyroxine fraction, which coincided with the significant decrease of TSH level. The other components (AFT4, T4, T3) in serum at this time were decreased or unchanged. The finding suggests the role of free thyroxine fraction in feed-back regulation of TSH secretion.Acknowledgment. We thank Dr A. Parlow and the NIAMDD, Rat Pituitary Hormone Distribution Program, for material for rat TSH immunoassay; Dr J. Nauman (Inst. Postgrad. Med., Warsaw, Poland) for T3 antibody, and to Ing. J. Sadlo, Mrs M. t'astná and Miss R Fajkoová for technical assistance. 相似文献
157.
Summary
2O,6N-butyryl, 3, 5-cyclic monophosphate (dibu cAMP) when added to fetal rat heart cells in culture inhibits myocyte contraction. This inhibition is 100, 84 and 51% complete when the dibu cAMP concentration used is 2, 0.2 and 0.02 mM, respectively. The potency of dibu cAMP derivatives in myocyte contraction inhibition follows the order, dibu cAMP>
6N-bu cAMP>
2O-bu cAMP=AMP>butyrate. The inhibition caused by the first three chemicals is greater than 70%.The author was a Moss Heart Fellow and acknowledges the technical assistance of Ms Martha Peet. This work was supported in part by the American Heart Association, National Science Foundation and American Cancer Society. 相似文献
158.
Summary In young spontaneously hypertensive rats (SHR), dopamine -hydroxylase (DBH) and phenylethanolamine N-methyltransferase (PNMT) activities were examined in the brainstem nuclei. Activation of noradrenergic neurons in the locus coeruleus, A2 and spinal intermediolateral cell areas, resulting in enhanced sympathetic nervous activity in the periphery, initiates hypertension. Adrenergic neurons, unchanged in these and A1 cell areas of young SHR, are not involved in the development of hypertension in SHR. 相似文献
159.
Summary The seedling growth ofBrassica campestris var.varuna, has been studied, as affected by water-stress and gibberellin treatments. A boost in the net GA response due to water-stress, has been observed. Thus presence of GA can overcome the water-stress effects.Publication No. 26 from Dept of Biosciences, Himachal Pradesh University, Simla. Authors are grateful to CSIR, New Delhi, for JRF to SB. 相似文献
160.
D. K. Bhatt 《Cellular and molecular life sciences : CMLS》1978,34(12):1549-1550
Summary Phenylketonuric squirrels have shown marked inhibition of alkaline phosphatatase in the olfactory lobes and cerebral hemispheres, whereas the Na+-K+-ATPase remained less altered. In the pathogenesis of phenylketonuria inhibition of alkaline phosphatase at the level of Blood-Brain Barrier (BBB), leads transport system to impaired functioning.This work was done in the Department of Zoology, University of Udaipur, Udaipur-313001, India. 相似文献