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41.
Sex‐biased gene expression,sexual antagonism and levels of genetic diversity in the collared flycatcher (Ficedula albicollis) genome
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42.
Berenjian Atefeh Sharifi Seyed Davood Mohammadi-Sangcheshmeh Abdollah Ghazanfari Shokoufe 《Biological trace element research》2018,184(2):474-481
Biological Trace Element Research - Chromium (Cr), as an essential trace element, plays a critical role in carbohydrate, protein, and lipid metabolism in animals. It has been suggested that the... 相似文献
43.
Hadi Rezaei Yazdi Ghorban Behzadian Nejad Shahin Najar Peerayeh Mohammad Mostafaei 《Annals of microbiology》2007,57(2):293-295
Of the 126 isolates obtained from clinical specimens, seventy strains were selected because of resistance or reduced susceptibilities to imipenem and/or ceftazidime. Screening for detection of MBL-producing strains was performed in latter isolates by the Etest MBL strips. Isolates that were positive to Etest MBL strips were analysed by PCR. PCR was performed with specific DNA probes for detection of genes coding IMP or VIM enzymes and positive controls (MBL-producing strains). Finally, eight isolates ofPseudomonas aeruginosa were detected to carry a blaVIM gene. 相似文献
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46.
Neda Soltani Ramezan Ali Khavari-Nejad Mojtaba Tabatabaei Yazdi Shadman Shokravi Eduardo Fernández-Valiente 《World journal of microbiology & biotechnology》2006,22(6):571-576
Summary Our objective was to evaluate the physiological response of Fischerella ambigua FS18 to the combined influence of pH (5, 7 and 9) and light intensity (3 and 300 μmol photon m−2 s−1). Growth rates were similar at pH 9 and pH 7. There was no growth at pH 5. Increasing light intensity did not have any considerable
influence on growth rates. Chlorophyll concentration was higher at pH 7 at all light intensities. Chlorophyll concentration
decreased with increasing light intensity from 3 to 300 μmol photon m−2 s−1. Synthesis of the phycobiliproteins (PBP), phycocyanin (PC) and allophycocyanin (APC) had the highest rate in pH 7. Increasing
irradiance decreased the concentrations of all PBPs. The light-saturated photosynthetic rate was clearly higher at high light
intensity. With respect to nitrogenase activity, the highest rate was at pH 9 and 300 μmol photon m−2 s−1. Irradiance did not affect significantly this activity at pH 7. This cyanobacterium seems to be alkalophilic with maximum
nitrogenase activity and photosynthesis at pH 9. It can also adapt its photosynthetic apparatus to the variable factors that
are found in rice fields. 相似文献
47.
Abolghasem Tohidpour Shahin Najar Peerayeh Jalil F. Mehrabadi Hadi Rezaei Yazdi 《Current microbiology》2009,59(3):352-355
In Gram negative bacteria, fluoroquinolone resistance is acquired by target mutations in topoisomerase genes or by reducing
the permeation of drugs due to the increase in expression of endogenous multidrug efflux pumps that expel structurally unrelated
antimicrobial agents. An ongoing challenge is searching for new inhibitory substances in order to block efflux pumps and restore
the antibiotic drugs susceptibility. In this research, we sought to investigate the interplay between ciprofloxacin and an
efflux pump inhibitor (EPI), phenyl alanine arginyl β-naphtylamide (PAβN), to determine the prevalence of efflux pump overexpression
in clinical isolates of Pseudomonas aeruginosa. Ciprofloxacin was tested at different concentrations (256–0.25 μg/ml) with a fixed concentration of PAβN (50 μg/ml). The
isolates susceptibility profiles were analyzed by disc diffusion and agar dilution methods using 10 antibiotic discs and 4
powders. It was found that in the presence of PAβN, resistance to ciprofloxacin was inhibited obviously and MIC values were
decreased. The comparison between subgroups of P. aeruginosa isolates with different resistance profiles indicates that efflux pump overexpression (EPO) is present in 35% of ciprofloxacin
resistant isolates with no cross resistance and in variable frequencies among isolates showing cross resistance to other tested
antibiotics: gentamicin (31%), ceftazidime (29%), and imipenem (18%). Altogether, these results imply that PAβN maybe effective
to restore the fluoroquinolone drugs susceptibility in clinical treatment procedures. Results also show that increased use
of a fluoroquinolone drug such as ciprofloxacin can affect the susceptibility of P. aeruginosa to other different antipseudomonal agents. 相似文献
48.
Background
Selection schemes aiming at introgressing genetic material from a donor into a recipient line may be performed by backcross-breeding programs combined with selection to preserve the favourable characteristics of the donor population. This stochastic simulation study investigated whether genomic selection can be effective in preserving a major quantitative trait locus (QTL) allele from a donor line during the backcrossing phase.Methods
In a simulation study, two fish populations were generated: a recipient line selected for a production trait and a donor line characterized by an enhanced level of disease resistance. Both traits were polygenic, but one major QTL affecting disease resistance was segregating only within the donor line. Backcrossing was combined with three types of selection (for total merit index) among the crossbred individuals: classical selection, genomic selection using genome-wide dense marker maps, and gene-assisted genomic selection. It was assumed that production could be observed directly on the selection candidates, while disease resistance had to be inferred from tested sibs of the selection candidates.Results
Classical selection was inefficient in preserving the target QTL through the backcrossing phase. In contrast, genomic selection (without specific knowledge of the target QTL) was usually effective in preserving the target QTL, and had higher genetic response to selection, especially for disease resistance. Compared with pure genomic selection, gene-assisted selection had an advantage with respect to disease resistance (28–40% increase in genetic gain) and acted as an extra precaution against loss of the target QTL. However, for total merit index the advantage of gene-assisted genomic selection over genomic selection was lower (4–5% increase in genetic gain).Conclusion
Substantial differences between introgression programs using classical and genomic selection were observed, and the former was generally inferior with respect to both genetic gain and the ability to preserve the target QTL. Combining genomic selection with gene-assisted selection for the target QTL acted as an extra precaution against loss of the target QTL and gave additional genetic gain for disease resistance. However, the effect on total merit index was limited. 相似文献49.
Sepideh Torabi Matthias Wissuwa Manzar Heidari Mohammad‐Reza Naghavi Kambiz Gilany Mohammad‐Reza Hajirezaei Mansoor Omidi Bahman Yazdi‐Samadi Abdelbagi M. Ismail Ghasem Hosseini Salekdeh Dr. 《Proteomics》2009,9(1):159-170
Mineral deficiency limits crop production in most soils and in Asia alone, about 50% of rice lands are phosphorous deficient. In an attempt to determine the mechanism of rice adaptation to phosphorous deficiency, changes in proteome patterns associated with phosphorous deficiency have been investigated. We analyzed the parental line Nipponbare in comparison to its near isogenic line (NIL6‐4) carrying a major phosphorous uptake QTL (Pup1) on chromosome 12. Using 2‐DE, the proteome pattern of roots grown under 1 and 100 μM phosphorous were compared. Out of 669 proteins reproducibly detected on root 2‐DE gels, 32 proteins showed significant changes in the two genotypes. Of them, 17 proteins showed different responses in two genotypes under stress condition. MS resulted in identification of 26 proteins involved in major phosphorous deficiency adaptation pathways including reactive oxygen scavenging, citric acid cycle, signal transduction, and plant defense responses as well as proteins with unknown function. Our results highlighted a coordinated response in NIL in response to phosphorous deficiency which may confer higher adaptation to nutrient deficiency. 相似文献
50.
New ammonoid species of the genus Araxoceras (A. abarquense sp. nov. and A. iranense sp. nov.) are described from the Early Dzhulfian (Early Wuchiapingian) beds of the Hambast Formation of Central Iran (Abade).
The data on the distribution of Paraceltites (Paraceltites sp.) and Vedioceras (V. umbonovarum Ruzhencev), for the first time discovered in the Dzhulfian beds of Abade, and of Eoaraxoceras are provided. The correlation of the Late Permian assemblages of ammonoids of Iran and Transcaucasia is amended. 相似文献