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91.
N. V. Shamina Zh. M. Mukhina N. M. Kovaleva V. A. Filiurina 《Cell and Tissue Biology》2011,5(2):186-195
The paper presents previously undescribed abnormalities of phragmoplast formation in pollen mother cells of grass haploids
and allohaploids (wide hybrids of the first generation). These abnormal phenotypes reveal and illustrate occasional unknown
stages of phragmoplast formation in dividing plant cells and indicate the special regulation of their initiation, as well
as confirm data on this process obtained by other approaches. 相似文献
92.
93.
M. V. Sidorova A. S. Molokoedov A. A. Az'muko E. V. Kudryavtseva E. Krause M. V. Ovchinnikov Zh. D. Bespalova 《Russian Journal of Bioorganic Chemistry》2004,30(2):101-110
The use of hydrogen peroxide for the formation of disulfide bridges was studied in 15 peptides of various lengths and structures. The oxidation of peptide thiols by hydrogen peroxide was shown to proceed under mild conditions without noticeable side reactions of Trp, Tyr, and Met residues. Yields of the corresponding cyclic disulfides were high and mostly exceeded those obtained with other oxidative agents, in particular, iodine. It was established that the use of hydrogen peroxide in organic medium also provided sufficiently high yields when large-scale syntheses of oxytocin and octreotide (up to 10 g) were carried out. 相似文献
94.
Hai-Yun Xiao Aaron Balog Ricardo M. Attar David Fairfax Linda B. Fleming Christian L. Holst Gregory S. Martin Lana M. Rossiter Jing Chen Mary-Ellen Cvjic Janet Dell-John Jieping Geng Marco M. Gottardis Wen-Ching Han Andrew Nation Mary Obermeier Cheryl A. Rizzo Liang Schweizer Thomas Spires Weifang Shan Gregory Vite 《Bioorganic & medicinal chemistry letters》2010,20(15):4491-4495
A novel series of 4-[3,5-dioxo-11-oxa-4,9-diazatricyclo[5.3.1.02,6]undec-4-yl]-2-trifluoromethyl-benzonitriles has been synthesized. The ability of these compounds to act as antagonists of the androgen receptor was investigated and several were found to have potent activity in vitro and in vivo. 相似文献
95.
Aim: To study genotypic diversity of isolates of Brochothrix thermosphacta recovered from meat, poultry and fish. Methods and Results: A total of 27 bacteria isolated from 19 samples of meat, poultry and fish were identified phenotypically and genotypically using PCR amplification of 16S‐23S rDNA intergenic transcribed spacer (ITS‐PCR), repetitive sequence‐based PCR (rep‐PCR) and 16S rDNA sequencing. Using ITS‐PCR, all bacteria showed the same DNA profile as the reference strains of Br. thermosphacta, allowing typing of the isolates at species level. Using 16S rDNA sequencing, all isolates were identified, at genus and species level, as Br. thermosphacta. Identification as Br. campestris was observed with a lower, but very close, level of similarity. Rep‐PCR was more discriminatory than ITS‐PCR and allowed differentiation of four subgroups among the isolates. Conclusion: Minor genotypic differences among Br. thermosphacta strains from meat, poultry and fish were observed. Significance and Impact of the Study: A rudimentary exploration of genotypic differences of Br. thermosphacta from meat, poultry and fish resulted in preliminary confirmation of the suitability of ITS‐PCR for typing Br. thermosphacta and confirmed the value of rep‐PCR fingerprinting to discriminate between Br. thermosphacta strains. 相似文献
96.
A possibility of alternative prognostication of the autumn abundance of fleas was shown by means of statistical analysis of prognostication tables made up on the basis of the distribution of informative factors: indices of the abundance of the great gerbil, which is the main host of fleas, weather conditions and characteristics of the populations of the fleas. 相似文献
97.
Isaria fumosorosea is one of important entomopathogenic fungi showed a good potential in controlling Bemisia tabaci. The effects of I. fumosorosea ⊿Ifchit1 mutant (Ifchit1 gene deletion mutant) on the mortality, oviposition, and host immunological response of B. tabaci, on Brassica campestris L. plant, were evaluated under laboratory conditions. The wild-type fungal strain infection significantly increased insect mortality and reduced the oviposition effeciency of B. tabaci, whereas the ⊿Ifchit1 mutant was much less effective, resulting in higher survival and ovipositing of B. tabaci. The activities of four insect enzymes were examined during a time course of fungal infection. Insect phenoloxidase, perioxidase, and catalase activities were decreased in whiteflies treated with the wild type and mutant I. fumosorosea strain at 12–36?h post treatment. However, these enzyme activities increased in fungal-treated whiteflies as compared to controls between 36 and 60?h post-infection, reaching peak values. Superoxide dismutase activity in fungal-treated whiteflies was higher than that in controls during the entire experimental time course examined. The overall enzyme activity profiles in ⊿Ifchit1 mutant-treated whiteflies were significantly different from wild-type strain treatments. Our results showed that loss of the Ifchit1 gene in I. fumosorosea affects whitefly mortality, ovipositioning and various antioxidant enzyme activities, providing new insights into the role of chitinases in I. fumosorosea-insect host–pathogen interactions. 相似文献
98.
Soil water use strategy of dominant species in typical natural and planted shrubs in loess hilly Region北大核心CSCD 下载免费PDF全文
Aims Artemisia gmelinii is a dominant specie naturally established after abandonment of cultivated lands in the Loess Plateau, and Caragana korshinskii is one of the main planted shrub species to control soil erosion. Improved understanding of water use strategies of these two species is of great significance to evaluate the sustainable development of the Loess Plateau under the trend of climate warming and increasing drought events. Methods Stable oxygen-18 isotope was used to determine seasonal variations in the water sources of native A. gmelinii communities established after abandonment of cultivated lands for 7 and 30 years and planted C. korshinskii after 30 years. The contributions of soil water from different depths to water uptake were estimated by the MixSIR Bayesian mixing model. The geometric mean regression method was used to fit the line of precipitation to get the local meteoric water line (LWML). Important findings The stable hydrogen isotope rate (δD) and stable oxygen isotope rate (δ18O) of soil water and xylem water plotted to the right side of the LWML, indicating that the isotopic compositions of soil water were enriched due to evaporation. The native A. gmelinii communities established after abandonment of cultivated lands for 7 years and planted C. korshinskii after 30 years showed plasticity in switching water sources from different soil layers, extracting water from shallow soil (0-40 cm) when soil water was available, but deeper soil (40-80 cm) when shallow soil water was dry. In contrast, A. gmelinii growing in site after cultivation abandonment for 30 years mainly relied on water from the surface soil (0-10 cm) throughout the growing season. Our results suggest that the ability of A. gmelinii to compete for soil water reduces with aging of the community while the planted C. korshinskii will have competitive advantage under the condition of increasing frequency of drought events in the future. 相似文献
99.
100.
Y. V. Rakhimova G. A. Nam B. D. Yermekova U. K. Jetigenova B. Zh. Yessengulova 《Contemporary Problems of Ecology》2017,10(5):511-523
Two fungal-like organisms (class Oomycetes) and 263 species of fungi from 111 genera, 42 families, 23 orders, and 7 classes have been found on the territory of Aksu-Zhabagly Nature Reserve. Twenty-two species are found for the first time. The vast majority of species are parasitic (202 species), 56 species belong to saprotrophs, and 7 to symbiotrophs. Classes Taphrinomycetes, Urediniomycetes, and Ustilaginomycetes are represented exclusively by parasites. There have been found 21 saprotrophic, 27 parasitic, and 4 symbiotrophic species in the class Ascomycetes. The most numerous group in the class Basidiomycetes is the group of humus saprotrophs; it contains 15 species. Groups of litter saprotrophs and parasites contain four species each, symbiotrophic species have three species, coprotrophs and xylotrophs have two species each, and litter and humus saprotrophs have one species each. Anamorphic fungi are represented by 91 parasitic and 11 saprotrophic species. In comparison with closely located Sairam-Ugam National Park and the Karatau Nature Reserve, the mycobiota of Aksu-Zhabagly is characterized by a significant number of species in the classes Basidiomycetes, Urediniomycetes, Hyphomycetes, and Coelomycetes. Thirty-one species are common to these protected areas. The most numerous group is parasites. 相似文献