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331.
The species of Adialytus Förster in Iran are taxonomically studied and new data on distribution and host associations are presented. The existence of a species complex, in the case of Adialytus ambiguus (Haliday), and the morphological variability in commonly used taxonomic characters has been discussed. In total, four valid species belonging to the genus Adialytus including Adialytus ambiguus (Haliday), Adialytus salicaphis (Fitch), Adialytus thelaxis (Starý) and Adialytus veronicaecola (Starý) have been identified and recorded from Iran. Also, we recognized two additional phenotypes: “Adialytus arvicola” (Starý) and “Adialytus cf. ambiguus” (Haliday). These phenotypes and Adialytus veronicaecola are newly recorded from Iran in association with Sipha and Aphis species, respectively. An illustrated key for identification of the species and two variable phenotypes is presented.  相似文献   
332.
Different cellular mechanisms contribute to the hearing sense, so it is obvious that any disruption in such processes leads to hearing impairment that greatly influences the global economy and quality of life of the patients and their relatives. In the past two decades, transmembrane inner ear (TMIE) protein has received a great deal of research interest because its impairments cause hereditary deafness in humans. This evolutionarily conserved membrane protein contributes to a fundamental complex that plays role in the maintenance and function of the sensory hair cells. Although the critical roles of the TMIE in mechanoelectrical transduction or hearing procedures have been discussed, there are little to no review papers summarizing the roles of the TMIE in the auditory system. In order to fill this gap, herein, we discuss the important roles of this protein in the auditory system including its role in mechanotransduction, olivocochlear synapse, morphology and different signalling pathways; we also review the genotype-phenotype correlation that can per se show the possible roles of this protein in the auditory system.  相似文献   
333.
Soil improvement is one of the major concerns in civil engineering. Therefore, a variety of approaches have been employed for different soil types. The loose granular soils and sediments have always imposed challenges due to their low strength and bearing capacity as well as presenting difficulties in drilling and excavation. Biomediated soil improvement, i.e., utilizing some bacteria to precipitate calcite on soil particles, has recently been introduced as a novel link of biotechnology and civil engineering to improve the problematic soils. Biogrout as a branch of biomediated soil improvement is based upon microbial calcium carbonate precipitation (MICP). In the present study, the Taguchi method with the aim of optimizing the process was utilized to design the experiments (DOE). A standard L9 orthogonal array with four parameters comprising bacterial cell concentration, molar concentration ratio of nutrient solution, curing time, and flow rate, each assigned to three levels, was selected. In this regard, soil samples were stabilized in sandy soil columns. Two-phase injections were conducted by injecting the bacterium Sporosarcina pasteurii PTCC 1642 in the first phase and nutrient in the second phase. Specimens were subjected to an unconfined compressive strength (UCS) test. ANOVA pointed out how effectual each parameter was. The most effective parameter was curing time, which accounted for 45.97% of the overall variance of the experimental data followed by bacterial cell concentration (22.01%), nutrient strength (19.98%), and flow rate (12.04%). Predicted UCS values for the optimum condition were validated in a confirmation test. Indeed, the UCS of the soil increased from 85 kPa in the control sample to 930 kPa for the optimally treated specimen. It was concluded that rather than curing time, the other parameters are almost equally influential in the applied injection procedure.  相似文献   
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335.

Phytase is an important enzyme poses great nutritional significance in humans and monogastric animals diets. The phytase production yield using wild sources, including micro-organisms, plants, and animals is sorely low. Thus, recombinant expression of phytase has received increasing interest for achieving production rate. Escherichia coli is the most preferred host for expression of heterologous proteins but overexpression of recombinant phytase in E. coli, met with limited success due to the sequestration of the enzyme into inclusion bodies. In the present study, artificial phytases gene with excellent thermostability and activity were designed by detecting the enzymatic region of the E. coli phytase gene by employing bioinformatics tools. Then, the PCR amplified recombinant gene was expressed in E. coli and the active enzyme was recovered from inclusion bodies. Employing cysteine amino acid in the dialysis buffer succeed to the superior activity of the enzyme with a specific activity of 73.8 U/mg. The optimum temperature and pH for enzyme activity were determined at 60 °C and 4, respectively. The novel recombinant enzyme illustrated perfect thermostability up to 70 °C with maintenance 75% of its activity. The enzyme was stable at pH range of 2–10. Moreover, the effects of ions and chemical compounds on enzyme stability and activity were assessed.

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336.
In vivo tracking and monitoring of adoptive cell transfer has a distinct importance in cell‐based therapy. There are many imaging modalities for in vivo monitoring of biodistribution, viability and effectiveness of transferred cells. Some of these procedures are not applicable in the human body because of low sensitivity and high possibility of tissue damages. Shortwave infrared region (SWIR) imaging is a relatively new technique by which deep biological tissues can be potentially visualized with high resolution at cellular level. Indeed, scanning of the electromagnetic spectrum (beyond 1000 nm) of SWIR has a great potential to increase sensitivity and resolution of in vivo imaging for various human tissues. In this review, molecular imaging modalities used for monitoring of biodistribution and fate of administered cells with focusing on the application of non‐invasive optical imaging at shortwave infrared region are discussed in detail.  相似文献   
337.
The aim of this study was to improve the production of an extracellular alkaline lipase from Alcaligenes sp. (ATCC 31371) by optimization of the culture medium, for economic production of biodiesel from waste vegetable oil. A number of carbon sources including different types of starch, sugar, sugar alcohol, organic acids, and surfactants were investigated. Polyoxyethylene (20) sorbitan tristearate, whose side chain is stearic acid, was the most effective carbon source for lipase production. Box-Behnken experimental design was used for three factors (soy protein, sodium nitrate, and stearic acid) and the optimal composition for maximum lipase production (1.7-fold enhancement) was established as soy protein 4.07%, sodium nitrate 0.17%, and stearic acid 0.28% at 28°C with an agitation rate of 220 rpm for 24 h. The enzyme was purified to homogeneity and the recovery of the lipase activity was 7.8% with a 30-fold purification. The estimated molecular size of the protein determined by SDS-PAGE was 33 kDa. The optimum pH and temperature of the purified lipase was 8.5 and 40°C, respectively. The purified enzyme was stable in the pH range of 6.0 and 9.5 and in the temperature range of 20 and 50°C.  相似文献   
338.
Persian poppy (Papaver bracteatum Lindl.) is an important medicinal plant and source of the opium alkaloids codeine, morphine and thebaine. Transgenic root cultures of P. bracteatum Lindl. are well-defined model systems to investigate the molecular and metabolic regulation of benzylisoquinoline alkaloid biosynthesis. Agrobacterium rhizogenes was able to produce hairy roots on wounded Persian poppy seedlings. Excised shoots from 7-day-old Persian poppy were co-cultivated with the A. rhizogenes strain R15834 carrying the pBI121 binary vector. All media, except for the co-cultivation medium, included 40 mg l−1 paromomycin to select for pBI121 transformants and 200 mg l−1 cefotaxime to eliminate the Agrobacterium. Eight weeks after infection, paromomycin-resistant roots appeared on 45–50% of explants maintained on hormone-free medium. Isolated hairy roots were propagated in liquid medium containing 1.0 mg l−1 1-naphthaleneacetic acid to promote rapid growth. Also, callus induction and shoot regeneration of transformed Calli in vitro was achieved on B5 medium containing 1.0 mg l−1 1-naphthaleneacetic acid. Detection of the neomycin phosphotransferase gene and GUS histochemical localization confirmed the integrative transformation of root cultures. This is the first study to illustrate useful protocol to introduce foreign genes into transgenic Persian poppy hairy root cultures using A. rhizogenes strain R15834.  相似文献   
339.
doi:10.1111/j.1741‐2358.2009.00313.x
Prevalence of oral and dental disorders in institutionalised elderly people in Rasht, Iran Objective: The aim of this study was to determine the prevalence of dental and oral mucosal lesions in institutionalised elderly people in Rasht. Background: Oral health in the elderly people is important to tailor the health programmes for this increasing age group within the population. Methods: A total of 216 elderly people residing in a geriatric nursing home were included in the study. Subjects were interviewed and examined clinically and registered in a data collection form and analysed using spss version 11 program (SPSS Inc, Chicago, Illinois, USA). Results: The prevalence of dental and oral disorders was 44.9% and 86.1% respectively. The most frequent oral disorders were dry mouth (42.1%), fissure tongue (25.9%), atrophic of tongue (25%), sublingual varicosity (22.7%), burning sensation (16.7%) and varix (15.3%). The prevalence of edentulousness was 56% (95%CI: 49–63%). The mean level of retained teeth was 3.22. The odds of an oral mucosal disorder in females were significantly more than in males (OR = 2.79, 95%CI: 1.25–6.23). Discussion: The findings revealed a high prevalence of dental and oral disorders in institutionalised elderly people in Rasht in comparison to similar studies. The mean of retained teeth was also much lower than in other reports. Therefore, the necessity for regular oral examination of these rapidly expanding age groups of people is essential.  相似文献   
340.
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