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971.
972.
Yoshinari Maeda Kiyoshi Yoshimura Hiroto Matsui Yoshitaro Shindo Takao Tamesa Yukio Tokumitsu Noriaki Hashimoto Yoshihiro Tokuhisa Kazuhiko Sakamoto Kouhei Sakai Yutaka Suehiro Yuji Hinoda Koji Tamada Shigefumi Yoshino Shoichi Hazama Masaaki Oka 《Cancer immunology, immunotherapy : CII》2015,64(8):1047-1056
973.
Kazuhiro Nomura Takao Hoshino Kathy Knebel Marvin Barker 《In vitro cellular & developmental biology. Plant》1978,14(2):174-179
Summary Autoradiographic and flow microfluorometry analyses have been applied to a study of perturbed cell kinetics in 9L rat brain
tumor cells treated with dibutyryl cyclic AMP and theophylline alone and in combination in vitro. At a concentration of 1
mM each, cell growth ceased shortly after the administration of these drugs. The results indicate that cells in S and G2 phase at the time of drug administration can undergo mitosis even though a considerable prolongation of G2 phase was apparent. However, cells in G1 at the time of drug administration were arrested in that phase whereas those cells in S or G2 were able to complete one mitosis before becoming arrested in the G1 phase. This blocking effect was reversible, and cells resumed proliferation at a normal rate shortly after the removal of
these drugs.
This work was supported in part by NIH Cancer Research Center Grant CA-13525 and CA-19992 from NCI, and by the Association
for Brain Tumor Research.
Presented at the 6th International Cell Cycle Conference, March, 1976, New Orleans, Louisiana.
The tumor used in this study was provided by William H. Sweet, Paul T. Kornblith, Janette L. Messer and Beverly O. Whitman
of the Massachusetts General Hospital, Boston, Massachusetts. 相似文献
974.
Takao Ubukata YOKO NAKAGAWA 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2000,33(4):313-329
The geometry of the external shell sculpture in the Late Cretaceous inoceramid bivalve Inoceramus hobetsensis Nagao & Matsumoto, 1939 was studied both empirically and theoretically. A large sample, collected from the Upper Cretaceous of Hokkaido, Japan, shows remarkably high intraspecific variation in the shell sculptural pattern. Quasi-commarginal ribs, slightly oblique to the external growth increments, occur in some specimens. These sculptures are commonly irregular in strength and spacing, and their features are successfully modelled by computer simulations when the commarginal ribs are superposed with nearly concentric divaricate rib. Computer models indicate that the divergent sculpture element, often found in other inoceramids, was present throughout the evolution of I. hobetsensis and was developing in the evolutionary lineage from I. hobetsensis nonsulcatus to I. hobetsensis hobetsensis, although it was only weakly expressed. The results also suggest that some apparently distinct sculptural patterns of I. hobetsensis are the result of minor changes in the morphogenetic program. 相似文献
975.
976.
Formation of 3',5'-O-(dialkylsilanediyl)deoxyribonucleosides was studied. Treatment of deoxythymidine in DMF with bifunctional silylating reagent such as di-t-butyldichlorosilane and diisopropyldichlorosilane in the presence of imidazole gave the expected silanediyl derivatives. The structure was confirmed mainly by NMR spectroscopy. The stability of these cyclic silyl derivatives toward hydrolysis is also described. 相似文献
977.
978.
Masahira Nakagawa Heiichi Sakai Akira Isogai Akira Hirota 《Bioscience, biotechnology, and biochemistry》2013,77(9):2279-2283
Four neutral sesquiterpenes were isolated from the culture filtrate of of Aspergillus terreus THOM NO. 14 which produces two sesquiterpene antibiotics, terrecyclic acid A and terrecyclol. On the basis of spectroscopic data the structures of four neutral sesquiterpenes were elucidated. One of these is quadrone, a known antitumor substance, but isoquadrone, 8-hydroxyquadrone and 6-hydroxyisoquadrone are new sesquiterpenes. Although terrecyclic acid A exhibits antimicrobial and antitumor activities, these four scarcely show these activities. 相似文献
979.
A cell-free preparation of human neutrophils catalyzing NADPH-dependent conversion of leukotriene B4 总被引:2,自引:0,他引:2
H Sumimoto K Takeshige H Sakai S Minakami 《Biochemical and biophysical research communications》1984,125(2):615-621
The sonicate of human neutrophils converted leukotriene B4 to a polar product in aerobic condition in the presence of NADPH at a rate comparable to that of the intact cells. NADH could scarcely replace NADPH. The conversion was not observed in anaerobic conditions and was inhibited by carbon monoxide (CO/O2 = 4/1) or by 1 mM p-chlormercuribenzoate, while it was not affected by 1 mM KCN, 5 mM NaN3, 200 micrograms/ml catalase, 100 mM mannitol, and 10 micrograms/ml superoxide dismutase. These observations suggest that the myeloperoxidase-H2O2-halide system and active oxygen species are not involved in the reaction. The activity was observed in the 100,000xg supernatant from the homogenate, in which cytochrome P-450 was not detected. 相似文献
980.
The presence of rhodopsin-like protein was detected in the head of the freshwater planarian Dugesia japonica japonica Ichikawa et Kawakatsu by use of anti-frog-rhodopsin rabbit IgG. Two membrane proteins of molecular weights 65000 and 62000 were separated by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis and found to react with the anti-rhodopsin IgG. The antibody may be useful for monitoring regeneration of the planarian eye. 相似文献