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331.
Omid Karami Ali Deljou Gona Karimi Kordestani 《Plant Cell, Tissue and Organ Culture》2008,92(3):273-280
This is the first report describing culture conditions necessary to induce secondary embryogenesis in two carnation cultivars,
Nelson and Spirit. In the first step, embryogenic calli were induced on petal explants followed by development of primary
somatic embryos from the calli. In the second stage, secondary somatic embryos were obtained when precotyledonary and cotyledonary
primary embryos were isolated and transferred onto a series of culture media all containing MS basal salt mixture, and supplemented
with different concentrations of 2,4-D, BA, sucrose and mannitol. The highest rate of secondary embryogenesis occurred on
mannitol containing media. Secondary somatic embryos were converted into plantlets when they were transferred onto growth
regulator-free half-strength MS medium and successfully acclimated in the greenhouse. 相似文献
332.
Evidence for the presence of Ctenocephalides orientis in livestock dwellings in northwest Iran 下载免费PDF全文
S. J. Seyyed‐Zadeh F. Bozorg‐Omid Z. Telmadarraiy O. Terenius A. R. Chavshin 《Medical and veterinary entomology》2018,32(3):383-387
Fleas are important vectors of diseases such as murine typhus, tularaemia, hymenolepiasis and plague. The presence of active foci and history of human‐ and flea‐transmitted plague in northwest Iran prompted the present group to collect and identify fleas from human and livestock dwellings across West Azerbaijan Province. Adult fleas were collected and identified using routine taxonomic keys. Species designation was confirmed by sequencing the cytochrome oxidase subunit I (COI). Of the collected specimens (n = 989), 104 were collected off‐host (30 from human dwellings and 74 in light traps) and the rest were found on hosts (107 on animals and 778 by human bait). Of these fleas, 394 (40%) were male and 595 (60%) were female. The collected specimens belonged to the species Ctenocephalides canis, Ctenocephalides felis, Ctenocephalides orientis and Pulex irritans (all: Siphonaptera: Pulicidae). The amplified COI fragment, in addition to confirming the morphological identification of species, showed good efficacy in separating the different species in the phylogenetic analysis. In addition to the identification of fleas from human and livestock dwellings using morphological and molecular characteristics, the current paper represents the first report of the presence of C. orientis in northwest Iran. This finding suggests that changing climate conditions may have expanded the distribution of this species. 相似文献
333.
AbstractCommunicated by Ramaswamy H. Sarma 相似文献
334.
Atousa Moradzadegan Seyed‐Omid Ranaei‐Siadat Azadeh Ebrahim‐Habibi Mohammad Barshan‐Tashnizi Rouhollah Jalili Seyed‐Fakhraddin Torabi Khosro Khajeh 《Engineering in Life Science》2010,10(1):57-64
Electrospinning, a simple and versatile method to fabricate nanofibrous supports, has attracted continuous attention in the field of enzyme immobilization. In this study, acetylcholinesterase (AChE) has been successfully immobilized in PVA nanofibers via electrospinning of a mixture of AChE, BSA as an enzyme stabilizing additive and PVA. The maximum activity recovery of immobilized AChE was about 40%. In comparison with free enzyme, the immobilized AChE showed improved stability while retaining a considerable amount of activity at lower pH values. Moreover, the immobilized AChE retained >34% of its initial activity when stored at 30°C for 100 days and retained 70% of its initial activity after ten consecutive reactor batch cycles. 相似文献
335.
336.
N Fotouhi B R Bowen D S Kemp 《International journal of peptide and protein research》1992,40(2):141-147
The acyl transfer rate for proline, in the prior thiol capture strategy, was enhanced by changing the electronic character of the dibenzofuran template. The rate of amide bond formation between proline and cysteine by the 1-chloro-4-hydroxy-6-mercaptodibenzofuran was measured to be 0.012 min-1, which translates to a half-life of 53 min. Further enhancement of the reaction rate was accomplished by the use of a 1,3-dichloro-dibenzofuran template. The k1 for the reaction was measured to be 0.093 min-1, and the half-life was calculated to be 7 min. To test the applicability of the activated template, 1-chloro-4-hydroxy-6-mercaptodibenzofuran, in peptide synthesis, the 34 amino acid long peptide, H-RPDFCLEPPYTGPCRKARNNFKSADECMRTCGGA-OH, was synthesized. This peptide represents the condensation of the N-terminal 13-mer and the C-terminal 21-mer of the basic pancreatic trypsin inhibitor. 相似文献