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91.
Infections with high levels of gentamicin-resistant (HLGR) isolates of Enterococcus faecalis are common in Tehran hospitals. Genes encoding such resistance are transmissible by conjugation at high frequency. The purpose of this study was to determine the existence of Tn5281 and its flanking aminoglycoside modifying enzyme gene aac(6')-aph(2") among 102 HLGR isolates of E. faecalis cultured from patients at three hospitals in Tehran, Iran. These isolates were detected by disks containing 120 microg of gentamicin and made 65% of all E. faecalis during the study period. DNA was extracted from HLGR isolates and subjected to PCR assays targeting aac(6')-aph(2") and conjugative transposon Tn5281. The amplified aac(6')-aph(2") gene was labeled with digoxigenin and probed with Tn5281 amplicons in dot blot hybridization assays. The aac(6')-aph(2") gene was detected in 91%-92% (n = 93) of the HLGR isolates. All isolates containing aac(6')-aph(2") were positive in long-PCR targeting Tn5281 and the probe hybridized with Tn5281 amplicons. The number of HLGR isolates of E. faecalis has increased considerably in Tehran hospitals. Tn5281 is the main cause of transmission of aac(6')-aph(2") to different isolates of E. faecalis in the hospitals studied. 相似文献
92.
Derakhshan Samira Aminishakib Pouyan Pirzadeh Fatemeh Rahrotaban Sedigheh Farzaneh Parvaneh Tavakoli Shiraji Sahar Ganjibakhsh Meysam Asadi Masoumeh 《Molecular biology reports》2021,48(4):3223-3235
Molecular Biology Reports - Aflibercept and arsenic trioxide drugs apply a cytotoxic effect on some human cancer cell lines. However, no more study has followed the effects of both drugs,... 相似文献
93.
Parisa Farrokh Mojgan Sheikhpour Alibakhsh Kasaeian Hassan Asadi Roya Bavandi 《Biotechnology progress》2019,35(5):e2835
Cyanobacteria are photosynthetic microorganisms which can be found in various environmental habitats. These photosynthetic bacteria are considered as promising feedstock for the production of the third- and the fourth-generation biofuels. The main subject of this review is highlighting the significant aspects of the biofuel production from cyanobacteria. The most recent investigations about the extraction or separation of the bio-oil from cyanobacteria are also adduced in the present review. Moreover, the genetic engineering of cyanobacteria for improving biofuel production and the impact of bioinformatics studies on the designing better-engineered strains are mentioned. The large-scale biofuel production is challenging, so the economic considerations to provide inexpensive biofuels are also cited. It seems that the future of biofuels is strongly dependent to the following items; understanding the metabolic pathways of the cyanobacterial species, progression in the construction of the engineered cyanobacteria, and inexpensive large-scale cultivation of them. 相似文献
94.
Li Tai Fang Pegah Tootoonchi Afshar Aparna Chhibber Marghoob Mohiyuddin Yu Fan John C. Mu Greg Gibeling Sharon Barr Narges Bani Asadi Mark B. Gerstein Daniel C. Koboldt Wenyi Wang Wing H. Wong Hugo YK Lam 《Genome biology》2015,16(1)
SomaticSeq is an accurate somatic mutation detection pipeline implementing a stochastic boosting algorithm to produce highly accurate somatic mutation calls for both single nucleotide variants and small insertions and deletions. The workflow currently incorporates five state-of-the-art somatic mutation callers, and extracts over 70 individual genomic and sequencing features for each candidate site. A training set is provided to an adaptively boosted decision tree learner to create a classifier for predicting mutation statuses. We validate our results with both synthetic and real data. We report that SomaticSeq is able to achieve better overall accuracy than any individual tool incorporated.
Electronic supplementary material
The online version of this article (doi:10.1186/s13059-015-0758-2) contains supplementary material, which is available to authorized users. 相似文献95.
96.
Speck M Cho YM Asadi A Rubino F Kieffer TJ 《American journal of physiology. Endocrinology and metabolism》2011,300(5):E923-E932
Dramatic improvement of type 2 diabetes is commonly observed after bariatric surgery. However, the mechanisms behind the alterations in glucose homeostasis are still elusive. We examined the effect of duodenal-jejunal bypass (DJB), which maintains the gastric volume intact while bypassing the entire duodenum and the proximal jejunum, on glycemic control, β-cell mass, islet morphology, and changes in enteroendocrine cell populations in nonobese diabetic Goto-Kakizaki (GK) rats and nondiabetic control Wistar rats. We performed DJB or sham surgery in GK and Wistar rats. Blood glucose levels and glucose tolerance were monitored, and the plasma insulin, glucagon-like peptide-1 (GLP-1), and glucose-dependent insulinotropic polypeptide (GIP) levels were measured. β-Cell area, islet fibrosis, intestinal morphology, and the density of enteroendocrine cells expressing GLP-1 and/or GIP were quantified. Improved postprandial glycemia was observed from 3 mo after DJB in diabetic GK rats, persisting until 12 mo after surgery. Compared with the sham-GK rats, the DJB-GK rats had an increased β-cell area and a decreased islet fibrosis, increased insulin secretion with increased GLP-1 secretion in response to a mixed meal, and an increased population of cells coexpressing GIP and GLP-1 in the jejunum anastomosed to the stomach. In contrast, DJB impaired glucose tolerance in nondiabetic Wistar rats. In conclusion, although DJB worsens glucose homeostasis in normal nondiabetic Wistar rats, it can prevent long-term aggravation of glucose homeostasis in diabetic GK rats in association with changes in intestinal enteroendocrine cell populations, increased GLP-1 production, and reduced β-cell deterioration. 相似文献
97.
A survey of aflatoxins in sesame in Iran 总被引:1,自引:0,他引:1
A study of the occurrence of aflatoxins (AF) in sesame seeds was conducted in the Khorasan province of Iran between September
2009 and August 2010. Samples (n = 182) were analyzed by liquid chromatography (LC), and detection limits for AFB1, AFB2, AFG1 and AFG2, were 0.45, 0.19, 0.61, and 0.22 ng/g, respectively. AFB1 was detected in 33 samples (18.1%), at a mean level of 1.62 ± 1.32 ng/g, and a maximum level of 5.54 ng/g. AFB1 levels exceeded the European Union (EU) maximum tolerated level (MTL, 2 ng/g) in 9 samples, and the Iran MTL (5 ng/g) in
1 sample. Regarding total aflatoxins (AFT), the mean level was 0.92 ± 1.36 ng/g, and the maximum level was 5.54 ng/g. No sesame
sample exceeded the Iran MTL (15 ng/g), but two samples exceeded the EU MTL (4 ng/g) for AFT. It is concluded that low levels
of AFs occur frequently in sesame from Iran. 相似文献
98.
Mozaffar Asadi Khosro Mohammadi Sheida Esmaielzadeh Hoong-Kun Fun 《Inorganica chimica acta》2009,362(14):4913-4920
A set of two Cu(II) complexes, [Cu(cdXsalen)] and [Cu(cdXsalMeen)] derived from Schiff base ligands (H2cdXsalen: methyl-2-{[2-(2-X-phenyl)methylidynenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate and H2cdXsalMeen: methyl-2-{[1-methyl-2-(2-X-phenyl)methylidynenitrilo]ethyl}amino-1-cyclopenteneithiocarb-oxylate where X = hydroxyl, methoxy, nitro, sodiumsulfite, chloro, bromo and H2cdMesalen: methyl-2-{[2-(2-hydroxyphenyl)ethylidynenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate; H2cdPhsalen: methyl-2-{[2-(2-hydroxyphenyl)phenylidynenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate; H2cdMesalMeen: methyl-2-{[1-methyl-2-(2-hydroxyphenyl)ethylidynenitrilo]ethyl}amino-1-cyclopentenedithiocarboxylate; H2cdPhsalMeen: methyl-2-{[1-methyl-2-(2-hydroxyphenyl)phenylidynenitrilo]ethyl}amino-1-cyclopentenedi-thiocarboxylate) with an unsymmetric NNOS coordination sphere have been synthesized and characterized by elemental analysis, IR, UV-Vis and mass spectrometry. The thermodynamic formation constants of the complexes were measured spectrophotometrically, at constant ionic strength 0.1 M (NaClO4), at 25 °C in DMF solvent. The trend of the complex formation for copper is as follow:
[Cu(cdMesalen)]>[Cu(cdsalen)]>[Cu(cdPhsalen)][Cu(cdMesalMeen)]>[Cu(cdsalMeen)]>[Cu(cdPhsalMeen)] 相似文献
99.
The synthesis of thallium(III) chloride and bromide was performed in solution by chlorination and bromination, respectively, of the suspensions of the corresponding thallium(I) halides in acetonitrile. Crystalline compounds TlX3(CH3CN)2 (X = Cl−, Br−) were prepared from the acetonitrile solutions. Thallium(III) chloride and bromide in dimethylsulfoxide solution were obtained by dissolving the corresponding solid compounds TlX3(CH3CN)2 (Cl−, Br−) in DMSO. Both acetonitrile and dimethylsulfoxide solutions of thallium(III) chloride were studied by UV-Vis and 205Tl NMR spectroscopy. The UV-Vis study of the TlCl3-CH3CN system showed presence of at least two thallium(III) chloride species. Only one signal arising from the thallium(III) species was, however, detected by the 205Tl NMR in the solution because of the fast chemical exchange. The 205Tl NMR study of thallium(III) chloride in dimethylsulfoxide showed three separate signals assigned to the solvated , TlCl3 and species. The crystalline compounds of trichlorobis(dimethylsulfoxide)thallium(III) and tribromobis(dimethylsulfoxide)thallium(III) were prepared and their crystal structures were solved by single-crystal X-ray analysis. The thallium atom in the complexes has a trigonal bipyramidal environment built by three halide ions occupying equatorial positions of the polyhedron and two oxygen atoms of the DMSO molecules in the apical positions. 相似文献
100.
Persistent soil seed banks in old-growth Hyrcanian Box tree (Buxus hyrcana) stands in northern Iran 总被引:1,自引:0,他引:1
Hamed Asadi Seyed Mohsen Hosseini Omid Esmailzadeh Carol C. Baskin 《Ecological Research》2012,27(1):23-33
Little is known about the soil seed bank and the influence of plant communities on the interaction between the seed bank and
aboveground vegetation in the Hyrcanian temperate deciduous forest. We surveyed species composition and diversity of the persistent
soil seed bank and the aboveground vegetation in six community types in old-growth Hyrcanian Box tree (Buxus
hyrcana) stands in northern Iran. Fifty-two species with an average of 3,808 seeds/spores m−2 germinated; forbs accounted for 64% of the seed bank flora. Thirty-four species in the aboveground vegetation were not presented
in the seed bank, 32 species in the seed bank were not found in the vegetation, and 20 species were in both. The dominant
tree species were Diospyros lotus and Alnus subcordata with an average of 17 and 4.6 seeds m−2, respectively. Our results suggest that (1) vernal geophytes and shade-tolerant perennials are not incorporated in the seed
bank, (2) early successional species are well represented in the seed bank, (3) plant community type has significant impacts
on seed bank densities, and seed bank richness and diversity were significantly related to presence/absence of Box tree in
the aboveground vegetation. The persistent seed bank contained species that potentially have a negative impact on the regeneration
of forests, thus forest managers should retain old-growth Hyrcanian Box tree stands to conserve disturbance-sensitive indicator
forest species. 相似文献