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991.
Bacillus thuringiensis delta-endotoxin: evidence that toxin acts at the surface of susceptible cells 总被引:4,自引:0,他引:4
Enzymically activated delta-endotoxin of Bacillus thuringiensis covalently bound to Sephadex beads, has the same effect on insect cells in tissue culture as free toxin. The effect is prevented by antitoxin antibody and heat denaturation and is not due to a nonspecific protein effect, the beads, or toxin released from the beads. The toxin, therefore, probably acts at the cell surface. 相似文献
992.
B Desoize C Léger G Nahas 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,287(16):1441-1444
THC decreases 3H-thymidine uptake within 15 sec. after addition of the drug to the culture (L1210 murine lymphoma cells and human lymphocytes). Experiments performed at 0 degrees C indicate that THC has no action on thymidine binding to the carrier. THC in micromolar concentration inhibits DNA synthesis through a alteration of membrane configuration. 相似文献
993.
Summary CosmopolitanDrosophila species can survive wide ecological tolerances measured by resistance to desiccation/temperature extremes compared with endemic rain forest species. This, rather than any genetic features, is important in helping to explain the widespread distributions of cosmopolitan species.We thank Dr Lee Ehrman for cultures ofD. paulistorum, and the Australian Research Grants Committee for financial support. 相似文献
994.
Summary The formation of the myotomes to chick embryos was studied by using experimental and scanning electron microscope techniques. With the aid of the quail-chick marker system, it was demonstrated that the dermatome gives rise to the myotome plate. SEM studies support the conclusion that the myotome cells originate only from the edges of the dermatome.Supported by the Deutsche Forschungsgemeinschaft (Ch 44/2). 相似文献
995.
P. Puccetti A. Giampietri M. C. Fioretti 《Cellular and molecular life sciences : CMLS》1978,34(6):799-800
Summary 2 primary immune responses (anti-SRBC antibody response and allograft rejection) have been tested in mice at various time intervals after single doses of either DTIC or cyclophosphamide. The DTIC-induced immunodepression proved to be extremely long-lasting, being still detectable after 2 months.This work was supported by Project NO1-CB 64054 of the U.S.-Italy Cooperative Science Program. 相似文献
996.
997.
998.
999.
H Bartels R Bartels R Baumann R Fons K D Jürgens P Wright 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(16):1195-1198
A high oxygen capacity combined with a low oxygen affinity and a large Bohr effect achieve a high oxygen transport capacity in small shrews. The high metabolic rate (Suncus estruscus: 100 to 350 ml O2/kg. min) can be explained by the combination of the favorable blood parameters with a high relative heart weight (1,2% of body weight) and heart frequencies of 1,000 to 1,350 per minute. 相似文献
1000.
E Follénius M P Dubois 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(19):1383-1386
An immunocytological study of the basal hypothalamus of Carassius auratus and Cyprinus carpio with an alpha-endorphin antiserum shows the different nerve processes belonging probably to the immunoreactive cells of the lateral part of the N.L.T. According to their pathways, two main fibre tracts have been distinguished: many fluorescent fibres converge towards the pituitary gland into which they enter, other fibres run caudally through the tuber towards the nucleus tuberis inferior (Baumgarten and Braak) where they could not be followed further. 相似文献