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991.
992.
Gurdyal S. Besra David E. Minnikin Amin Sharif John L. Stanford 《FEMS microbiology letters》1990,66(1-3):11-13
Abstract Dtacyl phtluodlolone A and phenolphthtodlo-lone A hpids were isolated from two stratus of Mycobactertum ulcerans . The dlol umts of the phthione A and phenolphth]odlolone A components were shown to have erythro stercochemistry by infrared spectroscopy and proton nuclear magnetic resonance of an acetal derivative This stereoehemistry is shared only by related dvols from M. marmum , the dhols from M. boys, M kansasu, M leprae and M. luberculosiss having threo stereochemlstry. 相似文献
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996.
Maryam Sobhani Mohammad Amin Tabatabaiefar Asadollah Rajab Abdol-Mohammad Kajbafzadeh Mohammad Reza Noori-Daloii 《Gene》2013
Wolfram syndrome (WS) is a rare autosomal recessive neurodegenerative disorder that represents a likely source of childhood diabetes especially among countries in the consanguinity belt. The main responsible gene is WFS1 for which over one hundred mutations have been reported from different ethnic groups. The aim of this study was to identify the molecular etiology of WS and to perform a possible genotype–phenotype correlation in Iranian kindred. 相似文献
997.
The development of multi-cellular organisms involves a comprehensive and tightly regulated cell-to-cell communication system to coordinate the activity and behavior of individual cells. Diverse signaling pathways ranging from receptor-mediated signal transduction to contact-dependent communication via gap junctions achieve these complex interactions. In this review, we will focus on a new type of intercellular connection, the tunneling nanotube (TNT), which has been observed in many cell types in vitro and recently also in developing embryos of different species in vivo. We will summarize the latest insights into their functional roles in cell-to-cell signaling with a particular focus on the TNT-dependent electrical coupling between developing embryonic cells. Finally, potential implications of these new findings in the light of developmental processes, particularly in cell migration, will be discussed. 相似文献
998.
Twenty broad bean selections were screened for their relative susceptibility to the reniform nematode, Rotylenchulus reniformis, under greenhouse conditions at 20?±?5?°C. The degree of susceptibility was rated based on number of females per root system of each selection. Hence, G 3, L 47, L 49, L 52, L 57, L 71, L 92, L 99 and L 375 selections were graded as resistant hosts against the nematode infection and sex selections (G 429, L 13, L 16, L 24, L 31 and L 46) were categorised as moderately resistant. However, only the selection L 9 out of 20 selections was ranked as susceptible and four selections, namely L 50, L 101, L 241 and L 348, were rated as highly susceptible against R. reniformis infection. It was observed that reproduction of the nematode was favoured on highly susceptible and susceptible selections but inhibited on resistant ones. Therefore, all tested selections showed great variability in their reaction to the nematode infection according to the host type. Also, various plant growth parameters were discussed. Finally, the differences among the tested selections should serve as an informative resource for plant breeders and cropping systems to limit the loss due to the nematode infection. 相似文献
999.
Hamzeh Izadi Mahshid Sarnevesht Reihaneh Sadeghi Kamran Mahdian Mohammad Amin Jalai 《Archives Of Phytopathology And Plant Protection》2013,46(18):2236-2242
The common pistachio psylla, Agonoscena pistaciae, Burckhardt and Lauterer (Hemiptera: Psyllidae) is the key pest of pistachio orchards in Iran. Chemical control is the common method for the control of this pest. In this study, the effects of pyriproxyfen (an insect growth regulator), neemarin (a botanical insecticide), acetamiprid (a neonicotinoid) and Ferula assafoetida essential oil were investigated on the fifth instar nymphs of A. pistaciae. Probit analysis of concentration-mortality data was conducted to estimate the LC50 values. The LC50 values for neemarin, pyriproxyfen, acetamiprid and F. assafoetida essential oil were estimated to be 0.22, 0.52, 290 and 5.62 ppm, respectively. Our results showed that the fifth instar nymphs of A. pistaciae are very sensitive to neemarin and pyriproxyfen. 相似文献
1000.
Mohammad Ebrahimi Mohammad Hasan Safaralizade Oroj Valizadegan Bentol Hoda Hosaini Amin 《Archives Of Phytopathology And Plant Protection》2013,46(9):1093-1101
The cotton aphid, Aphis gossypii Glover (Hem: Aphididae), is one of the most injurious pests of fruits, vegetables and ornamental plants worldwide, both outdoor and indoor. Currently, the main method of control of this pest is through application of pesticides which is mostly accompanied by the resistance of the pest against pesticide(s). The resurgence of resistant aphid populations brings about further contamination of foodstuff and environment. Essential oils obtained from the aerial parts of plants may have the potential to be an alternative to synthetic pesticides, since they have been demonstrated to possess a wide range of bioactivities against insects and mites. So, the aim of the current study was to investigate the effect of essential oils extracted from three different plants namely: Azadirachta indica Adr. Juss. (Meliaceae), Eucalyptus camaldulensis Dehn. (Myrtaceae) and Laurus nobilis L. (Lauraceae) against A. gossypii. The LC50 values of essential oils of A. indica, E. camaldulensis and L. nobilis against A. gossypii were 1.96, 2.28 and 3.16?μl L?1 air, respectively. This shows that A. indica possesses the highest lethal activity whereas L. nobilis the lowest. These data suggest that essential oils of all the three plants have the potential to be employed in the pest management programmes designed for a control of A. gossypii under greenhouse conditions. 相似文献