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21.
用触角电位法研究了大豆蚜、棉蚜和桃蚜对39种挥发性次生化合物的反应,结果如下:1)绿叶气味化合物及其异构体的去极化电压远强于萜烯类;具有6个碳原子的醇类和醛类是最有活性的化合物.2)大豆蚜和棉蚜对醛类和脂类的反应要比对相应的醇类强,这与桃蚜的实验结果刚好相反.3)蚜虫嗅觉系统所显示的活性与刺激化合物的结构有关,醇类和醛类刺激所引起的EAG饱和的要比不饱和的强.4)大豆春迁蚜对萜烯衍生物(醇、醛、脂)的触角电位反应高于棉蚜,而对萜烃化合物的反应刚好相反.5)各种化合物引起的EAG峰形不同;牛儿醇、癸醇和香茅醇刺激所引起的波形回复最慢,而在直链饱和醇中随着碳原子数的增加而回复速度减慢. 相似文献
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Localization of juvenile, but not late-infantile, neuronal ceroid lipofuscinosis on chromosome 16. 总被引:1,自引:1,他引:0
W Yan R M Boustany C Konradi L Ozelius T Lerner J A Trofatter C Julier X O Breakefield J F Gusella J L Haines 《American journal of human genetics》1993,52(1):89-95
The neuronal ceroid lipofuscinoses (NCL) are a group of progressive neurodegenerative disorders characterized by the deposition of autofluorescent proteinaceous fingerprint or curvilinear bodies. We have found that CLN3, the gene underlying the juvenile form of NCL, is very tightly linked to the dinucleotide repeat marker D16S285 on chromosome 16. Integration of D16S285 into the genetic map of chromosome 16 by using the Centre d'Etude du Polymorphisme Humain panel of reference pedigrees yielded a favored marker order in the CLN3 region of qtel-D16S150-.08-D16S285-.04-D16S148-.02-D16S 67-ptel. The most likely location of the disease gene, near D16S285 in the D16S150-D16S148 interval, was favored by odds of greater than 10(4):1 over the adjacent D16S148-D16S67 interval, which was recently reported as the minimum candidate region. Analysis of D16S285 in pedigrees with late-infantile NCL virtually excluded the CLN3 region, suggesting that these two forms of NCL are genetically distinct. 相似文献
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Xiong Zhang Ming-You Peng En-Ming Feng Qing-Dan Li Lu Chen Hu-Cheng Yang Bing Guo Hong Liang Ying-Tong Di Lei Tang Ying Yan 《化学与生物多样性》2023,20(10):e202301061
Three previously undescribed diterpenoids, helioscopnoids A–C, and eight known compounds were isolated from the whole plants of Euphorbia helioscopia. Their structures were established by extensive analysis of spectra and data comparison with previous literatures. Among them, compound 4 was identified as 24,24-dimethoxy-25,26,27-trinoreuphan-3β-ol with revised configurations of C-13, C-14, and C-17 (13R*, 14R*, 17R*). Cytotoxicity assays revealed that all compounds exhibited varying levels of cytotoxicity against H1975 cells, with compound 9 displaying the most potent activity, as indicated by cell viability rates of 18.13 % and 20.76 % at concentrations of 20 μM and 5 μM, respectively. This study expands the understanding of E. helioscopia terpenoids’ structural diversity and biological activities, contributing to the exploration of potential therapeutic applications. 相似文献
26.
Mei-Ling Siu-Caldera Jeffrey W. Clark Anabela Santos-Moore Sara Peleg Yan Yun Liu Milan R. Uskokovi Surendra Sharma G. Satyanarayana Reddy 《The Journal of steroid biochemistry and molecular biology》1996,59(5-6)
1α,25(OH)2-16-ene-D3, a synthetic analog of the steroid hormone, 1α,25(OH)2D3, has great potential to become a drug in the treatment of leukemia and other proliferative disorders, because of its minimal in vivo calcemic activity associated with a potent inhibitory effect on cell growth. However, at present, the mechanisms through which 1α,25(OH)2-16-ene-D3 expresses its biological activities are still not completely understood. Our previous in vitro study in a perfused rat kidney indicated for the first time that 1α,25(OH)2-16-ene-D3 and 1α,25(OH)2D3 are metabolized differently. 1α,25(OH)2-24-oxo-16-ene-D3, an intermediary metabolite of 1α,25(OH)2-16-ene-D3 formed through the C-24 oxidation pathway, accumulated significantly in the perfusate when compared to 1α,25(OH)2-24-oxo-D3, the corresponding intermediary metabolite of 1α,25(OH)2D3. In a subsequent in vivo study, we also reported that 1α,25(OH)2-24-oxo-16-ene-D3 exerted immunosuppressive activity equal to its parent, without causing significant hypercalcemia. In order to establish further the critical role of 1α,25(OH)2-24-oxo-16-ene-D3, in generating some of the key biological activities ascribed to its parent, we performed the present in vitro study using a human myeloid leukemic cell line (RWLeu-4) as a model. Comparative target tissue metabolism studies indicated that 1α,25(OH)2-16-ene-D3 and 1α,25(OH)2D3 are metabolized differently in RWLeu-4 cells, and the differences were similar to the ones we previously observed in the rat kidney. The significant finding was the accumulation of 1α,25(OH)2-24-oxo-16-ene-D3 in RWLeu-4 cells because of its resistance to further metabolism. Biological activity studies indicated that both 1α,25(OH)2-16-ene-D3 and its 24-oxo metabolite produced growth inhibition and promoted differentiation of RWLeu-4 cells to the same extent, and these activities were several fold higher than those exerted by 1α,25(OH)2D3. In addition, the genomic action of each vitamin D compound was assessed in a rat osteosarcoma cell line (ROS 17/2.8) by measuring its ability to transactivate a gene construct containing the vitamin D response element of the osteocalcin gene linked to the growth hormone reporter gene. In these studies, both 1α,25(OH)2-16-ene-D3 and its 24-oxo metabolite exerted similar but potent transactivation activity which was several fold greater than that exerted by 1α,25(OH)2D3 itself. In summary, our results indicate that the production and slow clearance of the bioactive intermediary metabolite, 1α,25(OH)2-24-oxo-16-ene-D3, in RWLeu-4 cells contributes significantly to the final expression of the enhanced biological activities ascribed to its parent analog, 1α,25(OH)2-16-ene-D3. 相似文献
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神经节苷脂GM_3对小鼠腹腔常驻巨噬细胞(R-M)和Ge-132体内激活的巨噬细胞(Ge-132-M)的磷脂代谢转换有显著的影响,当这两种M在体外用GM_3处理时,表现出[ ̄(32)P]Pi和[ ̄3H]肌醇参入PI降低,参入PIP、PIP_2增加;但在[ ̄(32)P]Pi和[ ̄3H]胆碱参入PC上,R-M与Ge-132-M不同,即GM_3促进同位素前体参入R-M的PC,抑制它们参入Ge-132-M的PC.以上结果表明GM3可能提高了PI或PIP的磷酸激酶的活性,致使[ ̄(32)P]PIP和[ ̄(32)P]PIP_2增多,[ ̄(32)P]PI减少.激活的M(Ge-132-M)本身PC代谢转换率较R-M高,当Ge-132-M再受GM_3刺激,PC代谢转换率降低,这提示GM_3对激活的M的PC代谢转换有调节作用. 相似文献
29.
RFLP tagging of a salt tolerance gene in rice 总被引:10,自引:0,他引:10
A salt tolerant rice mutant (M-20) was obtained through selection in vitro. Its tolerance was stably inherited over eight generations and most traints between M-20 and its sensitive original 77–170 (Oryza sativa) were very similar. By deriving an F2 population of M-20 × 77–170 and splitting every F2 individual into two parts, with one part planted in normal conditions and another part in saline conditions, the inheritance of salt tolerance in rice was studied. Under normal conditions, there was no apparent segregation among F2 individuals. Under saline conditions, however, the segregation of traits was obvious. According to our standards, the ratio of salt sensitive:moderately-tolerant:tolerant plants was 25:42:18, in accordance with a 1:2:1 ratio. It suggested that the improvement of salt tolerance in our materials was induced by the mutation of a major tolerant gene which showed incomplete dominance. By use of 130 RFLP probes distributed throughout the rice genome, the gene was tagged by a single copy DNA probe, RG4, which was located on chromosome 7. The genetic distance between the salt tolerant gene and RG4 was 7.0 ± 2.9 cM. Based on the split method, a method which could be currently used to evaluate the damage of salt stress in rice was proposed. 相似文献
30.