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961.
Ikuo Obataya Tomoyuki Kotaki Seiji Sakamoto Akihiko Ueno Hisakazu Mihara 《Bioorganic & medicinal chemistry letters》2000,10(24)
As a model of artificial peroxidase, de novo designed three-α-helix proteins, 3α-H9 and 3α-H12, covalently bound to Fe(III)-mesoporphyrin IX were synthesized and examined for a peroxidase-like activity. The activity was regulated according to the positions of His residues in the proteins, and the His residues played a role in an acid–base catalytic function. 相似文献
962.
Noriko Yamada Shinobu Sakamoto Yoshio Sawasaki Hiroshi Nakajima Ryohei Okamoto 《Biochimica et Biophysica Acta (BBA)/General Subjects》1980,629(1):61-68
Thymidine kinase activity in immature and castrated adult rat uterus has been examined in respose to estrogen treatment. Following estrogen administration. it was found that immature uterine thymidine kinase activity was increased 30-fold after 24 h, but almost no effect was produced on castrated or non-castrated adult uterus. Uterine thymidine kinase activity was separated into three peaks (peak 1, 2 and 3) by means of DEAE-cellulose column chromatography. In response to estrogen, the thymidine kinase isozymes differed in adult and immature uteri. In immature uteri, marked and selective increase of the activity was found in peak I, whereas in adult only a slight increase in peak 2 activity was observed. The thymidine kinase activity in peak 1 and peak 2 were found to have different enzymatic properties and molecular weight, as determined by gel filtration of 125 000 for peak 1 and 100 000 for peak 2.From these results, it is suggested that estrogen induces specific thymidine kinase isozyme in immature uterus and that the isozyme may be involved in DNA synthesis. Such a induction mechanism seems to be lost during the development. 相似文献
963.
964.
Pepleomycin is a derivative of bleomycin, which is less toxic to the host but possesses greater antitumor activity. Experiments are described here in which Chinese hamster V-79 cells in culture and a murine squamous cell carcinoma in vivo have been used to obtain survival curves for pepleomycin alone or in combination with radiation. In both systems the survival curves for pepleomycin alone are biphasic, and this drug proved to be twice as effective as bleomycin. Further, in contrast to bleomycin, which showed simple additivity with radiation, pepleomycin potentiated radiation injury to the tumor cells both in vivo and in vitro. Therefore, pepleomycin may be superior to bleomycin not only in drug therapy but also in combined modality therapy. 相似文献
965.
966.
967.
The cellular effects of estrogens on neuroendocrine tissues 总被引:2,自引:0,他引:2
F Naftolin N J MacLusky C Z Leranth H S Sakamoto L M Garcia-Segura 《Journal of steroid biochemistry》1988,30(1-6):195-207
Estrogen action on sensitive neurons in the rat diencephalon has been studied by morphologic techniques; evidence of estrogen action at every level is presented, including tracts, cells, circuitry and subcellular organelles. The demonstration in the arcuate nucleus of estrogen-induced synaptic remodelling, estrogen-induced postsynaptic membrane phenotypes, changes in intracellular membranes and rapid estrogen actions on neuronal endo-exocytosis indicates that cellular estrogen actions may underlie the neuronal control of reproduction. 相似文献
968.
Takashi Hosoki Michiko Ando Takehito Kubara Morihiko Hamada Masato Itami 《Plant cell reports》1989,8(4):243-246
A procedure for the clonal propagation ofPaeonia lactiflora Pall. cvs. Takinoyosooi and Sarah Bernhardt through shoot tip culture is described. Half strength Murashige and Shoog (1962) medium supplemented with 0.5 mg/l 6-benzylaminopurine plus 1 mg/l gibberellic acid promoted formation and growth of axillary buds. Continuous shoot multiplication was achieved by vertically splitting the shoot axis and subsequent division of elongated axillary shoots every 36 days. High frequency (57–100%) of rooting was obtained on paper-bridge liquid medium supplemented with 1 mg/l indole-3-butyric acid. Half of the rooted plantlets were established on porous soil. Thus, 700 and 300 plants of cv. Takinoyosooi and Sarah Bernhardt could be theoretically obtained from a single bud in one year.Abbreviations BAP
6-benzylaminopurine
- GA
gibberellic acid
- NAA
a-naphthaleneacetic acid
- IBA
indole-3-butyric acid
- MS
Murashige and Skoog (1962) basal medium 相似文献
969.