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91.
Characterization of lizard venom hyaluronidase and evidence for its action as a spreading factor 总被引:5,自引:0,他引:5
A T Tu R R Hendon 《Comparative biochemistry and physiology. B, Comparative biochemistry》1983,76(2):377-383
Hyaluronidase was isolated from the lizard (Heloderma horridum horridum) crude venom. The chemical properties were characterized and compared to the same enzyme from other sources. The enzyme was found to be a single polypeptide chain with a molecular weight of 63,000 daltons. It possesses an isoelectric point and pH optimum of 5.0, and was observed to be extremely temperature sensitive. The role of hyaluronidase as a spreading factor which serves to aid in the diffusion of toxins has been suspected for a long time; yet no experimental proof has been offered until now. It was shown that hyaluronidase promotes the spread of the hemorrhagic area in mice when injected with hemorrhagic toxin. Thus experimental evidence is supplied for the first time that the enzyme plays a role as a "spreading factor" in the toxic action of venom. 相似文献
92.
Determination of Rubella Hemagglutination-Inhibiting Antibody in Whole Blood 总被引:1,自引:0,他引:1
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A technique is described for determination of rubella hemagglutination-inhibiting antibody in only 50 to 100 muliters of whole blood. 相似文献
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Relationship Between the Membrane Envelope of Rhizobial Bacteroids and the Plasma Membrane of the Host Cell as Demonstrated by Histochemical Localization of Adenyl Cyclase 总被引:2,自引:1,他引:1
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J. C. Tu 《Journal of bacteriology》1974,119(3):986-991
By using adenyl cyclase as a marker enzyme, the relationship between the membrane envelope of the bacteroids of rhizobia and the plasma membrane of the host cell was demonstrated histochemically. Electron-dense deposits were found on the outer surface of the plasma membrane of the host cell and on the inner surface of the membrane envelopes of the bacteroids, but not in vacuole membranes, endoplasmic reticula, Golgi apparatus, and mitochondrial membranes. The results suggest that the membrane envelopes of the bacteroids are closely related to the host plasma membrane, and that entry of the bacteroids into the cytoplasm is in a manner similar to endocytosis. 相似文献
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Vincent Marks Denys Fry P. A. L. Chapple Geoffrey Gray 《BMJ (Clinical research ed.)》1969,2(5650):153-155
Experience with urine analysis for morphine using thin-layer chromatography in 310 cases of real or possible heroin abuse showed that it was valuable not only in detecting improper drug use but also in monitoring treatment. The results of this test can be available routinely in 24, and exceptionally in five hours. A negative result implies that the subject has taken less than 10 mg. of heroin in the past 24 hours. 相似文献
100.
P. C. Vincent G. Borner A. D. Chanana E. P. Cronkite M. L. Greenberg D. D. Joel L. M. Schiffer P. A. Stryckmans 《Cell proliferation》1969,2(3):235-247
Some of the time parameters of the cell cycle in bovine thoracic duct lymphocytes have been estimated by analysing labeled mitoses curves, and by double labeling. The two methods gave similar estimates of Ts. Thus, Ts measured directly from labeled mitoses curves varied from 4 to 6 hr, while the estimates from double labeling were 4.8 and 4.5 hr. T G measured directly from labeled mitoses curves was 5 hr, and estimates of TG from the values of Ts ranged from 6.3 to 7.7 hr. The present data confirm the short generative cycle of large thoracic duct lymphocytes. Extracorporeal irradiation of the lymph (ECIL) had no detectable effect on the cell cycle or the fractional production rate of the lymphocytes. However, the calculated absolute production was reduced following ECIL, due to a decrease in the absolute number of cells present. The grain count over mitoses after ECIL was approximately one-half that found before ECIL. 相似文献