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111.
112.
Judith Polonsky Zoïa Varon Ch. Marazano Bernadette Arnoux G. R. Pettit J. M. Schmid M. Ochi H. Kotsuki 《Cellular and molecular life sciences : CMLS》1979,35(8):987-989
Summary 2 new limonoid-type terpenes have been isolated from an aqueous extract of seeds produced by the Eastern Himalayan (India) plantAphanamixis grandifolia Bl. By interpreting principally mass spectral and nuclear magnetic resonance data, the structures of 12-hydroxyamoorastatin (2b) and amoorastatone (3) were elucidated. Unequivocal evidence for the 12-hydroxyamoorastatin structural assignment was obtained by chemical conversion to sendanin (4). Amoorastatin derivative2b was found to significantly inhibit growth of the murine P388 lymphocytic leukemia cell lines but amoorastatone in the same system was inactive. In a comparative biological study, sendanin (4) and anthothecol (7) were also found significantly to inhibit growth of the P388 cell line, while rohitukin (8) and limonin (9) were found to be inactive.Part 63 of the series Antineoplastic Agents. For the previous contribution refer to G.R. Pettit, T.S. Krupa and R.M. Reynolds, Int. J. Peptide Protein Res., in preparation. The present investigation was supported in part by Public Health Research Grant No. CA-16049-05 from the National Cancer Institute, the Fannie E. Rippel Foundation, Mrs Mary Dell Pritzlaff, the Spencer T. and Ann W. Olin Foundation, Mr John F. Schmidt, and the Phoenix Coca-Cola Bottling Company. 相似文献
113.
Diego Reginensi Patricia Carulla Sara Nocentini Oscar Seira Abel Torres-Espín Andreu Matamoros-Angles Rosalina Gavín María Teresa Moreno-Flores Francisco Wandosell Josep Samitier Xavier Trepat Xavier Navarro José Antonio del Río 《Cellular and molecular life sciences : CMLS》2015,72(14):2719-2737
Olfactory ensheathing cell (OEC) transplantation emerged some years ago as a promising therapeutic strategy to repair injured spinal cord. However, inhibitory molecules are present for long periods of time in lesioned spinal cord, inhibiting both OEC migration and axonal regrowth. Two families of these molecules, chondroitin sulphate proteoglycans (CSPG) and myelin-derived inhibitors (MAIs), are able to trigger inhibitory responses in lesioned axons. Mounting evidence suggests that OEC migration is inhibited by myelin. Here we demonstrate that OEC migration is largely inhibited by CSPGs and that inhibition can be overcome by the bacterial enzyme Chondroitinase ABC. In parallel, we have generated a stable OEC cell line overexpressing the Nogo receptor (NgR) ectodomain to reduce MAI-associated inhibition in vitro and in vivo. Results indicate that engineered cells migrate longer distances than unmodified OECs over myelin or oligodendrocyte-myelin glycoprotein (OMgp)-coated substrates. In addition, they also show improved migration in lesioned spinal cord. Our results provide new insights toward the improvement of the mechanisms of action and optimization of OEC-based cell therapy for spinal cord lesion. 相似文献
114.
本文用光镜观察了七至十月人胎听皮层的发育。结果:1.Nissl染色材料四个月份的材料均呈现典型新皮层的六层结构,七至十月份皮层总厚度依次为0.97mm,1.04mm,1.79mm,和1.85mm;内颗粒层神经细胞的体积密度依次为13.64%、17.49%、26.03%和34.05%;面数密度为58.87个/mm~2、40.45个/mm~2、23.48个/mm~2和11.62个/mm~2;轴比为1:1.32、1:1.65、1:1.75和1:1.86;分散度为0.89、0.83、0.74和0.67。2.Golgi染色材料,可见听皮层内具有新皮层的各种类型神经元,其中最多为颗粒细胞,其次为锥体细胞、梭形细胞,最少为马蹄诺特氏细胞,所见细胞数量比依次为17:9:1:1;颗粒细胞的树突野围绕着胞体形成一环形,而锥体细胞的底树突野呈扇形,顶树突可延伸远离胞体,其长度七—十月份依次为11.71±5.34/am//am~3、13.04±4.06am/弘m~3、15.01±6、17弘心弘m~3和16.09±5、63弘m/pm~3;轴突长度依次为22.12±0.66am/11m~3、26.96±8.49tlm/弘m~3、30.69±11.44Fm/tam~3,和34.52±7.62弘m/pm~3。锥体细胞树突在七月份时无分支,八月份时可见一级分支,但无侧棘,九、十月份时可见2—3级分支,可见到大量无柄侧棘出现。 相似文献
115.
Résumé Pendant l'hypoglycémie insulinique (4 U/100 g), le hamster maintenu a 19°C présente une augmentation de l'adrénaline et de la noradrénaline plasmatiques, ainsi qu'une réduction de ces deux catécholamines dans les surrénales. Maintenu à 26°C, l'hypoglycémie se produit aussi bien avec 4 U/100 g d'insuline mais il n'y a pas de changements de l'adrénaline et noradrénaline du plasma et des surrénales. Pour obtenir des modifications, il est nécessaire d'augmenter la dose d'insuline à 8 U/100 g. En conclusion, la température extérieure a une influence marquée sur la réponse médullo-surrénale de l'hypoglycémie insulinique. 相似文献
116.
Summary The NADP-linked malic enzyme fromHalobacterium cutirubrum is strongly inhibited by acetyl-CoA and NADH, and rather weakly inhibited by oxaloacetate and glyoxylate, in the presence of very high KCl concentrations (3,M), considered physiological for the extremely halophilic bacteria.This work was supported by grants from the consejo Nacional de Investigaciones Científicas y Técnicas de la República Argentina, and the Consejo de Investigaciones de la Universidad Nacional de Rosario. JJC and MCV are members of the Carrera del Investigador Científico of the former and the latter institutions, respectively. 相似文献
117.
Summary The effect of i.v. infusion of glucose on the hepatic handling of bilirubin was examined in rabbits. A significant increase in the excretion of conjugated bilirubin into the bile was observed, accompanied by a decrease in bilirubinemia. Hepatic bilirubin concentrations were lowered and the UDP-glucose concentrations and liver UDP-glucuronosyl and UDP-glucosyl transferase activities increased. 相似文献
118.
Zusammenfassung Die interne-Bestrahlung in kleinen Dosen vergrössert den 5-Hydroxytryptamin-Inhalt des zentralen Nervensystems der Ratte: Gehirnrinde, Dyencephalus, Hypothalamus, Geruchbulbe, Mittelhirn und Rückenmark. Bei Experimenten mit höheren Dosen (über 500 rad) sinkt der 5-Hydroxytryptamin-Gehalt.
This work has been carried out under a grant from the International Atomic Energy Agency, Vienna; contract No. 95 RB/1-RB/2. 相似文献
This work has been carried out under a grant from the International Atomic Energy Agency, Vienna; contract No. 95 RB/1-RB/2. 相似文献
119.
M Dau?a J Hourdry 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(12):973-975
Treatment by thyroxine modified the specific activity of intestianl DNA in premetamorphic Alytes tadpoles. The activity decreased up to the 3rd day, and showed afterwards a peak which culminates on the 9th day. These results have been discussed in comparison with previous radioautographic observations. 相似文献
120.