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231.
Summary Autoradiographic, stereological and histological studies have been carried out to determine the origin of muscle fibre splitting which supposedly occurs during muscle hypertrophy. The results obtained clearly indicate that the supposedly split fibres are a transient response probably derived from satellite cells and are not derived from pre-existing fibres by true splitting. Similarly, increases in muscle fibre size are not achieved by recruitment of satellite structures as indicated by lack of myonuclear recruitment.Acknowledgment. This work was carried out with the aid of a grant from the Medical Research Council of Great Britain. The authors are grateful for the excellent technical assistance of Miss H. Caulton, M.J. Wild and M. Fenner. 相似文献
232.
Summary Growth-promoting alpha-globulin (GPAG), a specific serum protein complex which induces mitotic activity in continually replicating metazoan cells in vitro, was shown in this study to support growth of astrocytes and mesenchymal cells as well as process formation of nerve cells isolated from cerebral hemispheres of chick embryos. 相似文献
233.
T. Ohhashi T. Miyazawa T. Azuma M. Sakaguchi 《Cellular and molecular life sciences : CMLS》1981,37(4):377-378
Summary The conduction velocity of peristaltic movements of the canine ureter was measured under anaesthesia with a new type of diameter gauge using an image sensor. The peristaltic velocity was 34.1±6.2 mm/sec in 10 experiments. Noradrenaline at a low dosage of 1 g/kg i.v. reduced the resting diameter, increased the conduction velocity to 47–56 mm/sec, and approximately doubled the frequency of contraction. The application of acetylcholine also caused an increase in both frequency and conduction velocity (42–46 mm/sec). A plot of the conduction velocity against the mean period of peristaltic contraction was hyperbolic in shape. 相似文献
234.
Summary -Galactosidase activity in intact cells of 21 species ofStreptomyces was measured using ONPG hydrolysis, without addition of a permeabilizing agent. Differences in the induction efficiency of ONPG-hydrolytic activity by lactose or galactose, which could have taxonomic implications, were observed among the species. 相似文献
235.
J. M. Saavedra 《Cellular and molecular life sciences : CMLS》1981,37(9):1002-1003
Summary Adult spontaneously hypertensive rats (SHR) are less sensitive to painful stimuli than their normotensive controls, Wistar-Kyoto (WKY) rats. This difference can be eliminated by the specific opiate antagonist, naloxone, and by the -adrenergic blocking agent, propranol.Acknowledgment. The author wishes to thank Miss R. L. Holcomb for her editorial assistance. 相似文献
236.
Nicoletta Crespi-Perellino A. Guicciardi A. Minghetti C. Spalla 《Cellular and molecular life sciences : CMLS》1981,37(3):217-218
Summary
Claviceps purpurea 275 F.I. fed with -aminobutyric acid produces ergostine with the corresponding -hydroxy--aminoacid undiluted by endogenous aminoacid. Almost all the -aminobutyric acid not incorporated into the ergostine remains unchanged in the medium. The significance of these results in the biosynthesis of ergot alkaloids is discussed. 相似文献
237.
Summary A simple device is described, which permits us to quantify several parameters of spontaneous behaviour of small animals. Using this device with mice we obtained statistically satisfactory results, showing a strong genetic influence on the behavioural characteristics tested.We wish to thank Mr R. Laplace for technical help, Mr J. P. Arnould for electronic work as well as I.N.S.E.R.M.-SCR 3. 相似文献
238.
H. Takeuchi T. Morimasa M. Matsumoto 《Cellular and molecular life sciences : CMLS》1977,33(7):938-939
Summary Several peptides were separated from-chymotrypsin-treated physalaemin by high voltage paper electrophoresis, and inhibition of the excitability of a molluscan giant neurone (tonically autoactive neurone) by the tripeptide, Lys-Phe-Tyr, was demonstrated.We thank Dr Sadaaki Iwanaga of Osaka University and Dr Atsuo Inoue of Daiichi Pharmaceutical CO for their helpful advice and the donation of the tripeptide (Lys-Phe-Tyr). 相似文献
239.
In vivo studies indicated that the primary effects of E. coli endotoxin on hepatic clearance of sulfobromophthalein were at the excretory level. Newborns were more sensitive to the LPS than older animals. 相似文献
240.
C. Hegyvary 《Cellular and molecular life sciences : CMLS》1977,33(10):1280-1281
Summary Aldosterone (15 g BID) and methylprednisolone (8 mg QD) administration to female guinea-pigs augmented both the total and the specific activity of NaK-ATPase but not the activity of adenylate cyclase in the cardiac sarcolemma. The rise in NaK-ATPase was due to increase in the number of enzyme molecules; catalytic activity and ouabain-sensitivity of individual molecules did not change.Acknowledgments. This work was supported by grant 1 R01 HL16611 from the National Heart and Lung Institute of the National Institutes of Health, United States Public Health Service. I thank Mr Kooil Kang for his excellent technical assistance. 相似文献