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91.
Tatsuo Nakahara Makoto Hirano Takashi Matsumoto Toshihide Kuroki Yoshinori Tatebayashi Tetsuyuki Tsutsumi Kouji Nishiyama Hiroaki Ooboshi Kaoru Nakamura Hiroshi Yao Akio Shiraishi Michinori Waki Hideyuki Uchimura 《Neurochemical research》1990,15(6):609-611
DNA and RNA contents in 20 brain regions or nuclei of the rat were determined by a highly sensitive method using high-performance liquid chromatography with electrochemical detection. The high DNA and RNA contents were found in the hypothalamic nuclei, especially the median eminence-arcuate nucleus. These results may be available for the preparation of nucleic acids as the regional control. 相似文献
92.
Flavonoids inhibit the expression of heat shock proteins 总被引:14,自引:0,他引:14
N Hosokawa K Hirayoshi A Nakai Y Hosokawa N Marui M Yoshida T Sakai H Nishino A Aoike K Kawai 《Cell structure and function》1990,15(6):393-401
Cells exposed to several forms of stress, such as heat shock, transiently synthesize a group of proteins called heat shock proteins (hsps). Although many stressors other than heat shock are known to induce hsps, inhibitors of hsp expression have never been reported. Here we show that quercetin and several other flavonoids inhibit the synthesis of hsps induced by heat shock in two human cell lines, Hela cells and COLO320 DM cells. Quercetin inhibited the induction of hsp70 at the level of mRNA accumulation. This is the first report to describe the inhibition of hsp expression by reagents. 相似文献
93.
Hiroshi Yonemitsu Koichiro Shimomura Motoyoshi Satake Shunji Mochida Masahiko Tanaka Thoru Endo Akira Kaji 《Plant cell reports》1990,9(6):307-310
Hairy roots were obtained following inoculation of the stems of Lobelia inflata L. with Agrobacterium rhizogenes strain ATCC 15834. These hairy roots contained agropine and mannopine. In addition, lobeline was detected by HPLC and confirmed by mass spectrometry. Various media were tested for the growth of hairy roots as well as for the content of lobeline in hairy roots. The growth rate of hairy roots cultured in Nitsch and Nitsch's medium was approximately one third of those cultured in other media. The lobeline content of hairy roots (18–54 g/g dry weight) cultured in these media was the same order of magnitude compared with that of roots of L. inflata (24 g/g dry weight) cultivated in pots. The hairy roots cultured in Nitsch and Nitsch's medium were morphologically different from those cultured in other media.Abbreviations MS medium
Murashige and Skoog's medium
- 1/2 MS medium
one-half strength of the standard Murashige and Skoog's medium
- B5 medium
Gamborg's B5 medium
- NN medium
Nitsch and Nitsch's medium
- FW
fresh weight
- DW
dry weight 相似文献
94.
The seed coat surface morphology of Celtidaceae and Ulmaceae (Urticales) indicates a significant evolutionary diversity.Celtis, Chaetachme andPteroceltis (Celtidaceae) have a unique sculpturing with many crateriform holes; such holes occasionally sparsely occur in seeds ofAphananthe, Gironniera (Celtidaceae) andPlanera (Ulmaceae), but not in those of the nine remaining genera of the two families. The perforated seed coat further occurs in
at least some genera of all other urticalean families. A pattern of its occurrence in families and genera suggest that the
perforation represents a common archaic feature of all Urticales, rather than a feature derived many times independently within
the order. The seed coat of Celtidaceae and Ulmaceae seems to have lately lost the holes probably by a neotenic evolution:
one or more times within Celtidaceae, and one time in an ancestral line leading to all Ulmaceae. The derived reticulate seed
coat surface sculpturing, which is shared byGironniera (Celtidaceae) and some Ulmaceae, is probably the result of parallel evolution. On the basis of evidence from seed coat morphology
and other sources, close relationships ofLozanella, Parasponia andTrema within Celtidaceae, as well as variously distinct positions ofAmpelocera, Aphananthe andGironniera, are also discussed. 相似文献
95.
Twelve polyether compounds originating from dinoflagellates were tested for growth-inhibiting activities againstAspergillus niger, Penicillium funiculosum, Candida rugosa, Escherichia coli, Bacillus megaterium andStaphylococcus aureus by a paper disc method. These polyethers represent six groups of different skeletons and originate from three species;Prorocentrum lima, Dinophysis fortii andGambierdiscus toxicus. Potent antifungal activities were observed with okadaic acid and its two congeners, desulfated yessotoxin, and ciguatoxin but not with okadaic acid esters, prorocentrolide, pectenotoxin-1, yessotoxin, maitotoxin, and desulphated maitotoxin. The antifungal activities and mouse lethalities of the polyethers were markedly affected by slight modification of their structures. Antibacterial potency of the tested compounds was not significant. 相似文献
96.
Hiroki Yamaue Hiroshi Tanimura Takuya Tsunoda Makoto Iwahashi Masaji Tani Mikiko Tamai Masaya Inoue 《Biotherapy》1990,2(3):247-259
The tumor-infiltrating lymphocytes (TILs) were cultured with interleukin 2 (IL-2) to induce the activated killer cells possessing autologous tumor-killing activity, and analysed their cell surface phenotypes and assessed anti-tumor killing activity. Furthermore, the activated TILs were transferred into 7 patients adoptively resulting in complete remission in a patient with pancreatic cancer and partial remission in another patient with gastric cancer.The cytotoxic activities of activated TILs at 3 weeks-incubation was 72 ± 15, 42 ± 26, 27 ± 21 and 25 ± 15% against K562, Daudi, KATO-III and autologous tumor, respectively. The negative selection method, indicated that the killer cells recognizing autologous tumor cells consisted of CD4- or CD8-positive T lymphocytes and CD16- or CD56-positive natural killer cells. The activated TILs could not only lyse cultured tumor cell lines, but also autologous tumor cells. 相似文献
97.
Mitoshi Yokota Yutaka Tagawa Daikichi Okada Tooru Yasutake Yoshikazu Mine Hiroshi Ishikawa Kousei Miyashita Masao Tomita Sumihiro Tabuchi 《Biotherapy》1990,2(3):207-212
Pre- and postoperative intradermal administration of OK-432 enhanced the SU-PS skin reaction in patients with gastric cancer, but failed to prevent a fall in the NK activity induced by the operation.The change in NK activity was not associated with a change in the proportion of Leu 7-positive cells, but was related to Leu 11a-positive cells. Intradermal injection of OK-432 increased the proportion of Leu 7-positive cells in the patients in whom they accounted for less than 20% of lymphocyte population. The case was the same with Leu 11a-positive cells.Intravenous injection of OK-432 tended to increase suppressor-inducer T cells (CD4+2HA+ cells), B cells and Leu 7-positive cells. Particularly, the proportions of OK-M1-positive cells and MHC class II antigen-positive cells increased in all patients. Immunotherapy with OK-432 given intravenously at a dose of 0.1 KE appeared to be safe because no side effects were essentially observed. 相似文献
98.
T Miyake H Komura A Tokuhira T Yamamoto A Miyake O Tanizawa N Terada R Yamamoto S Yoshida M Tsuji 《The Journal of steroid biochemistry and molecular biology》1990,37(1):31-37
The effects of ascorbic acid (AsA)-deficiency on the development of mammary glands were investigated using mutant rats (osteogenic disorder syndrome rats; ODS rats) with hereditary inability to synthesize AsA. Female ODS rats of 21 days old were castrated and divided into two groups. One group was given AsA in their drinking water, and the other was not. All the rats received a daily injection of oestradiol-17 beta and progesterone (EP) from day 28 to day 49 of age. After EP treatment, the concentrations of AsA in the mammary glands of rats not given AsA were less than one tenth of those of rats given AsA and the contents of hydroxyproline in the mammary glands of the former rats were about half of those in the latter. Furthermore, the concentration of serum prolactin in rats not given AsA was reduced to about one third of that in rats given AsA. After EP treatment, whole mounts of mammary glands showed that in rats not given AsA the development of ducts was impaired and there was extensive accumulation of endbuds. Consistent with this finding, EP injections did not increase the area of parenchyma in the mammary glands of rats not given AsA, whereas they increased it about 2-fold in rats given AsA. Moreover, after EP treatment the amount of alpha-lactalbumin was significantly less in the mammary parenchyma of rats not given AsA than in that of rats given AsA. On the other hand, AsA deficiency did not impair the response of the mammary cells to insulin or prolactin in terms of DNA synthesis and alpha-lactalbumin production. These findings indicate that AsA deficiency impaired the development of mammary glands. This effect may be partly attributable to a defect in collagen synthesis in the mammary glands and a decrease in the concentration of serum prolactin. 相似文献
99.
100.