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排序方式: 共有459条查询结果,搜索用时 15 毫秒
101.
Matloub Azza Abdelmageed Gomaa Eman Zakaria Hassan Amira Ali Elbatanony Marwa Mahmoud El-Senousy Waled Morsy 《International journal of peptide research and therapeutics》2020,26(1):497-511
International Journal of Peptide Research and Therapeutics - Endophytic bacteria are able to produce unique bioactive compounds for various biotechnological applications. The intracellular and... 相似文献
102.
103.
Protoplasma - Many studies have been carried out to investigate the histological structure of the trachea in many species of birds. However, the cellular organization of the trachea in the mallard... 相似文献
104.
105.
Gatica-Arias A Farag MA Stanke M Matoušek J Wessjohann L Weber G 《Plant cell reports》2012,31(1):111-119
Hop is an important source of secondary metabolites, such as flavonoids. Some of these are pharmacologically active. Nevertheless,
the concentration of some classes as flavonoids in wild-type plants is rather low. To enhance the production in hop, it would
be interesting to modify the regulation of genes in the flavonoid biosynthetic pathway. For this purpose, the regulatory factor
PAP1/AtMYB75 from Arabidopsis thaliana L. was introduced into hop plants cv. Tettnanger by Agrobacterium-mediated genetic transformation. Twenty kanamycin-resistant transgenic plants were obtained. It was shown that PAP1/AtMYB75 was stably incorporated and expressed in the hop genome. In comparison to the wild-type plants, the color of female flowers
and cones of transgenic plants was reddish to pink. Chemical analysis revealed higher levels of anthocyanins, rutin, isoquercitin,
kaempferol-glucoside, kaempferol-glucoside-malonate, desmethylxanthohumol, xanthohumol, α-acids and β-acids in transgenic
plants compared to wild-type plants. 相似文献
106.
Isolation of high-quality RNA from pancreas is challenging because the organ contains large quantities of RNases and undergoes autolysis upon harvest. Here we present a simplified perfusion method of the pancreas using an RNase inhibitor. The technique consistently yields high-quality RNA from stored pancreas samples suitable for molecular biology applications, including quantitative RT-PCR. Yields are comparable to RNA isolated from pancreas immediately, but superior to RNA isolated from stored samples that were snap-frozen or immersed in an RNase inhibitor solution. In addition, when compared to the previously reported in situ ductal perfusion technique, our method does not cause histological artifacts. 相似文献
107.
Two new dimeric stilbene glucosides, tingitanol A (1) and tingitanol B (2) together with trans-resveratrol 3-O-glucopyranoside (3) in addition to three known isoflavones, 5-O-methylgenistein (4), 5-O-methylgenistein 7-O-β-d-glucopyranoside (5) and betavulgarin (6) have been isolated for the first time from the fresh bulbs of Iris tingitana Boiss. & Reut. Their structures were established on the basis of the spectral data and direct comparison with values from previously identified analogues. Additionally, the isolated compounds (1–6) were evaluated for the free radical scavenging activity. 相似文献
108.
Shaimaa M. Farag Eman E. Essa Sulaiman A. Alharbi Saleh Alfarraj G.M.M. Abu El-Hassan 《Saudi Journal of Biological Sciences》2021,28(9):5261
The development of different approaches to use agricultural residues as a source of high value-added products, become a must, especially after the problems emerged due to their accumulation. This contribution demonstrates the potential of agricultural residues, Linuim usitatissium (flax seed) and Nigella sativa (black seed) peels, as raw materials for the production of bioactive products, botanical insecticides, against Cx. pipiens, with deep analysis to their chemical constituents by gas chromatography-mass spectrometry, the larvicidal efficacies of the three crude extracts (methylene chloride, petroleum ether and methanol 70%) from the two plant waste peels were evaluated for the first time against the late third instar larvae of Cx. pipiens. Results indicated different lethal doses in larvae depending on the efficacy of organic solvent used. For both compounds methanol 70% extracts produced the highest dry yield. The most efficient solvent is petroleum ether in case of both flax and Black seed peels. Petroleum ether extract exhibited the highest toxicity against Cx. pipiens with an LC50 of 69.6383 ppm. The same results for black seed indicated that petroleum ether was the most efficient against Cx. pipiens with an LC50 of 40.7748 ppm. The study revealed for the first time the type of phytochemical constituents presents in peels of flax and black seeds using GC–MS analysis which revealed twenty-eight constituents among extracts of flax and black seed peels ranging from to 58.8711% to 99.99% of the total extracts. GC–MS profiling showed that a five constituents, 9-2-Methyl-Z, Z-3, 13 octadecadienol (terpenoid), 9,17-Octadecadienal, (Z)-, Nonanoic acid, 9-oxo-, methyl ester, 9,12-Octadecadienoic acid Z,Z and Octasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13,15,15-hexadecamethyl- have insecticidal activity beside many other biological activities as recorded from a variety of botanical extracts. While the constituents like Hexadecanoic acid, methyl ester and cis-9-Hexadecenal, both of them are larvicidal, cis-Vaccenic acid and 9-Oxononanoic acid showing only an insecticidal activity beside Undecanoic acid the mosquito repellent. The other six constituents Linoelaidic acid, Oleic Acid, Z-2-Octadecen-1-ol, 1-Methoxy-3-hydroxymethylheptane, Cis-11,14–Eicosadieonic acid-methyl ester and Heptasiloxane, 1,1,3,3,5,5,7,7,9,9,11,11,13,13-tetradecamethyl- are constituents of other plant extracts which showed as a whole an insecticidal activity. 相似文献
109.
Mostafa M. Ghorab Fatma A. Ragab Helmy I. Heiba Hanan A. Youssef Marwa G. El-Gazzar 《Bioorganic & medicinal chemistry letters》2010,20(21):6316-6320
Pyrroles and pyrrolo[2,3-d]pyrimidines were reported to act as potent anticancer agents, in this work, a series of novel 2-substituted-3-cyano-4-phenyl-pyrrole 5, 6, 11–18, and 5-phenyl-pyrrolo[2,3-d]pyrimidine derivatives 7–10, 19–24 bearing either sulfathiazole or sulfapyridine were synthesized. The structures of these compounds were confirmed by elemental analysis, IR, 1H NMR and mass spectral data. All the newly synthesized compounds were evaluated for their in vitro cytotoxicity against liver and breast cancer cell line (HEPG2 and MCF7). Most of the screened compounds showed interesting cytotoxic activities compared with the used reference drug (doxorubicin). The radiosensitizing ability of some of the synthesized compounds was studied and the results showed an increase in the cell killing effect of γ-radiation after combination with the tested compounds. 相似文献
110.
Nor-ent-kaurane diterpenes and hydroxylactones from Antennaria geyeri and Anaphalis margaritacea 总被引:1,自引:0,他引:1
Ahmed AA Hussein TA Mahmoud AA Farag MA Paré PW Wojcińska M Karchesy J Mabry TJ 《Phytochemistry》2004,65(18):2539-2543
In a study of Pacific Northwest plants of the Asteraceae family, a nor-ent-kaurane diterpene and a known diterpene, both displaying antibacterial activities, were isolated together with scopoletin and sitosterol-3-O-beta-glucopyranoside from the aerial parts of Antennaria geyeri. Anaphalis margaritacea afforded two hydroxylactones. The structures were established by one and two dimensional NMR techniques, IR and CIMS. 相似文献