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从云南中甸产细叶香茶菜 (Isodontenuifolia (W .W .Smith)Kudo)的地上部分分离得到 6个化合物 ,它们的结构通过波谱方法得到鉴定。其中化合物 1和 2为新的对映_贝壳杉烷二萜化合物 ,即细叶香茶菜甲素 (3β ,6α ,15 β_trihydroxy_1α ,7β_diacetoxy_11β ,16 β_epoxy_ent_kaurane) (1)和细叶香茶菜乙素 (1α,6α ,11β_trihydroxy_3β,7β_diacetoxy_ent_kaur_16_en_15_one) (2 )。 相似文献
104.
Considerable physiological and biochemical evidence suggests that plants, like animals, widely use intracellular signalling coupled to heterotrimeric G proteins. Yet, the molecular components of this machinery remained elusive until recently. We overview the work carried out during the last two decades, aimed at identification of the plant proteins involved in G protein-coupled signalling. The completion of the sequencing of the Arabidopsis genome now permits to assess whether plants possess signalling and regulatory components of this machinery corresponding to those known from animals. 相似文献
105.
I G Andreeva I A Vartanian E M Tsirul'nikov 《Zhurnal evoliutsionno? biokhimii i fiziologii》1991,27(1):70-74
Sensational thresholds of the skin of fingers, palm and forearm have been determined in 5 healthy subjects ageing from 20 to 49 years. About 100 summation curves were obtained. Critical duration of the electrical stimuli remained constant in various areas. Critical duration of ultrasonic stimulation increased from fingers to forearm. The data obtained together with those found in literature suggest that critical duration of the stimulus is associated with the diameter of nonmyelin nervous fibers which are affected by the stimulus increasing with the increase in fiber diameter. 相似文献
106.
E P Bers N B Andreeva T G Gazarian L G Vodop'ianova N S Romanova 《Zhurnal evoliutsionno? biokhimii i fiziologii》1987,23(4):481-486
Comparative studies have been made on the immunochemical properties of histone H5 in Salmonidae species. High degree of homology between these histones and H5 histone from Oncorhynchus tschawytscha was demonstrated by microcomplement fixation. Properties of H5 histones in fish and birds are discussed. 相似文献
107.
E D Kuznetsova L E Andreeva I A Serova A Trenkner V Z Tarantul 《Molekuliarnaia genetika, mikrobiologiia i virusologiia》1989,(4):6-10
The structure of the transgene has been analysed in a new series of experiments on the transfer of adenovirus SA7 DNA into the mice zygotes by microinjection technique. The previous data on SA7 DNA elimination from the genomes of different organs (sceletal muscles, heart, tail) have been confirmed and detailed for the F0 and F1 generations of transgenic animals. The left end of adenoviral genome has been shown to be predominantly transfered after microinjections of SA7 DNA into the mice zygotes. 相似文献
108.
The enzyme peroxidase was isolated from the leaves of the tobacco plant Xanthi (intact and infected with weakly (XY) and highly (XT) pathogenic strains of potato X-virus) and partially purified. The original extract (the 30,000 g supernatant) was purified by ammonium sulfate at 30--80% of saturation and by gel filtration through Sephadex G-25 and G-100 in 0.05 M tris-HCl buffer, pH 7.4 containing 17% sucrose. Disc electrophoresis revealed that both intact and infected plants contain 10 isoperoxidases. The electrophoregrams of isoenzymes from infected plants with the Rf values of 0.1, 0.48, 0.53 and 0.59 stained with benzidine produced a more intensive colouring as compared to the corresponding isoenzymes from intact plants. The total enzymatic activity for the plants infected with the XY and XT strains made up to 180% and 240% of that for the intact plants, respectively. The molecular weights of the peroxidase isoenzymes were found to be the same and equal to 40,000. Study of the thermostability at 60 degrees C and pH 7.0 showed that after 90 min the enzyme activity was 12.4% and 5.1% of the original one in intact and infected plants, respectively. The data obtained suggest that the activity, thermostability and synthesis of some peroxidase isoenzymes in tobacco plant leaves are affected by viral infection. 相似文献
109.
Z M Andreeva V A Nikonova T S Shobukhova L I Vaneeva N F Iankina 《Zhurnal mikrobiologii, epidemiologii, i immunobiologii》1985,(4):60-63
A variant of the immunoenzyme assay, reducing the duration of the assay procedure by 3 hours in comparison with the standard technique, is presented. This rapid variant is sufficiently sensitive and reproducible. 相似文献
110.