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701.
702.
In this report we describe the purification and characterization of a cytostatic factor from the bitter melon (Momordica charantia). As determined by gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), this purified factor is a single component with an apparent molecular weight of 11,000. The factor is not sensitive to boiling or to pretreatments with trypsin, ribonuclease (RNAse), or deoxyribonuclease (DNAse). As determined by radioactive precursor uptake studies, the purified factor preferentially inhibits RNA synthesis in intact tissue culture cells. Some inhibition of protein synthesis and DNA synthesis also occurs. The factor is preferentially cytostatic for IM9 human leukemic lymphocytes when compared to normal human peripheral blood lymphocytes. 相似文献
703.
704.
The characteristic pungency of the liverwort Wiesnerella denudata is due to a germacranolide, tulipinolide. In addition to the previously known sesquiterpene lactones, tulipinolide, zaluzanin C, zaluzanin D, 8α-acetoxyzaluzanin C and 8α-acetoxyzaluzanin D, a novel germacranolide, dihydrotulipinolide with a pseudoaxial configuration of the C-11 methyl bond has been isolated. Inhibitory activity against the germination and growth of roots of rice in the husk is due to the guaianolides. The fragrant odor of W. denudata is responsible for the high content of monoterpenoids, particularly, (+)-bornyl acetate. 相似文献
705.
Itoh Takeshi; Aiba Hiroji; Baba Tomoya; Hayashi Kouji; Inada Toshifumi; Isono Katumi; Kasai Hiroaki; Kimura Shigenobu; Kitakawa Madoka; Kitagawa Masanari; Makino Kozo; Miki Takeyoshi; Mizobuchi Kiyoshi; Mori Hirotada; Mori Tomoko; Motomura Kouji; Nakade Shinsuke; Nakamura Yoshikazu; Nashimoto Hiroko; Nishio Yoshitaka; Oshima Taku; Saito Noriko; Sampei Gen-ichi; Seki Yasushi; Sivasundaram Suharnan; Tagami Hideaki; Takeda Jun-ichi; Takemoto Keiko; Wada Chieko; Yamamoto Yoshihiro; Horiuchi Takashi 《DNA research》1996,3(6):379-392
The 465,813 base pair sequence corresponding to the 40.150.0min region on the genetic map of Escherichia coli K-12 (W3110)was determined. Analysis of the sequence revealed that thisregion contained at least 466 potential open reading frames,of which 187 (40%) were previously reported, 105 (23%) werehomologous to other known genes, 103 (22%) were identical orsimilar to hypothetical genes registered in databases, and theremaining 71 (15%) did not show a significant similarity toany other gene. At the 45.246.0 min region, we founda very large cluster of about 30 genes, whose functions areinvolved in the biosynthesis of polysaccharides as the componentsof outer membranes. In addition, we identified anew asn-tRNAgene, designated asnW, between the asnT and asnU genes and anew lysogenic phage attachment site as the cis-element. 相似文献
706.
Analysis of large and small plaque mutants of simian virus 40 using antisera prepared against each has revealed quantitative and possibly qualitative antigenic differences for each plaque type. A sensitive micro radioisotope precipitation test permitted evaluation of immunochemical similarities and differences of capsid antigens by inhibition of precipitation. 相似文献
707.
Two new guaiane-type sesquiterpene dilactones, porelladiolide and 3α,4α-epoxyporelladiolide and a new germacranolide, 3β-hydroxycostunolide, together with the previously known germacranolides, guaianolides, pinguisane-type sesquiterpenes, and a sacculatane-type diterpene dialdehyde have been isolated from the liverwort, Porella japonica and their structures have been established by the spectral evidence and some chemical transformations. Porelladiolide, 3α,4α-epoxyporelladiolide and the sesquiterpene with α-methylene γ-lactone group showed inhibitory activity toward the germination and growth of roots of rice in the husk. 相似文献
708.
The localization of the two major isoforms of protein kinase C (PKC), PKCα and PKCγ, present in normal and galactosemic bovine
lens epithelial cells in culture, was determined using PKC isoform-specific antisera and visualized with FITC-conjugated secondary
antisera. The results indicated that the localization of PKC changed upon exposure to 40 mM galactose after 1day. The subcellular
distribution of control cells was cytoplasmic and perinuclear for PKCα, while, in 40 mM galactose-treated cells, PKCα was
also localized to nuclei. In contrast, upon exposure to 40 mM galactose the PKCγ of the lens epithelial cells was observed
in nucleoli. These results suggest that the subcellular distribution of the PKC isoforms in bovine lens epithelial cells differs
and is altered upon exposure to 40 mM galactose.
Accepted: 7 January 1998 相似文献
709.
710.