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71.
72.
Rasool Rezaei 《Archives Of Phytopathology And Plant Protection》2013,46(19):2377-2391
Pseudomonas syringae pv. syringae (Pss) strains were isolated from almond, apricot, peach, pear, sweet cheery and wheat in Kohgiluye and Boyer-Ahmad, Kordestan, Fras and Chaharmahal and Bakhtiari provinces of Iran. The strains were examined for host specificity, the presence of virulence genes and pathogenicity on different hosts. After inoculation of isolates, in compatible reactions bacterial populations increased within six days of inoculation and final cell numbers increased several-fold over initial inoculum levels, but in incompatible reactions, bacterial populations declined within four days of inoculation. Almond, sweet cherry and wheat isolates induced progressive necrotic symptoms on almond leaves and stems. Apricot, peach and sweet cherry isolates induced necrotic lesions when inoculated on apricot leaves. On pear leaves and stems, only the pear isolate incited pathogenic reaction and isolates from other hosts did not. The syrB gene was detected in all of the tested isolates. Almond and pear isolates did not have the syrD gene. The sypA gene was detected in the almond, peach, pear and sweet cherry isolates while the sypB gene was detected in the apricot, peach, sweet cherry and wheat isolates. Almond, apricot, pear and wheat isolates gave negative results for the detection of nit gene. The gene Ach, was detected only in the peach isolate and gene hrmA, was detected only in the wheat isolate. This study indicates that host specificity exists among different Pss strains, and genes responsible for syringomycin and syringopeptin production contribute to the virulence of Pss strains. 相似文献
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74.
Pamela H. Scott Nicola J. Veitch Helen Gadegaard Muhammad Mughal Gethin Norman Michelle Welsh 《Journal of biological education》2018,52(2):184-195
Laboratories are recognised as central in science education, allowing students to consolidate knowledge and master practical skills, however, their effectiveness has been questioned. Whilst laboratory practicals are useful for students’ learning of basic procedures, they have been shown to be less effective for developing conceptual understanding of the subject. Interactive lectures and bespoke digital resources were utilised in order to enhance theoretical understanding of laboratory practical molecular sessions, thus enabling students to take responsibility for and direct their own learning, encouraging inquiry-based learning. Providing easy to access additional learning resources offered students an opportunity to better prepare themselves for the laboratory, and consolidate their knowledge through subsequent review and self-testing in their own time. Grades before and after implementation of these active learning strategies were analysed to look at the impact on student learning and this study demonstrates that integrating these into a challenging practical biology course improved grades significantly with a concomitant increase in the number of ‘A’ grades attained. Feedback to evaluate use and perceptions of both interactive lectures and digital resources were also analysed. It has been shown here that these activities enhanced student experience and understanding of the course. 相似文献
75.
In vitro antibiofilm and anti‐adhesion effects of magnesium oxide nanoparticles against antibiotic resistant bacteria
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Sumreen Hayat Saima Muzammil Muhammad Hidayat Rasool Zonaira Nisar Syed Zajif Hussain Anjum Nasim Sabri Saba Jamil 《Microbiology and immunology》2018,62(4):211-220
76.
Ehsan Ullah Mughal Asif Javid Amina Sadiq Shahzad Murtaza Muhammad Naveed Zafar Bilal Ahmad Khan Sajjad Hussain Sumrra Muhammad Nawaz Tahir Khalid Mohammed Khan 《Bioorganic & medicinal chemistry》2018,26(12):3696-3706
The prime objective of this research work is to prepare readily soluble synthetic analogues of naturally occurring 3-O-flavonol glycosides and then investigate the influence of various substituents on biological properties of synthetic compounds. In this context, a series of varyingly substituted 3-O-flavonol glycosides have been designed, synthesized and characterized efficiently. The structures of synthetic molecules were unambiguously corroborated by IR, 1H, 13C NMR and ESI-MS spectroscopic techniques. The structure of compound 22 was also analyzed by X-ray diffraction analysis. All the synthetic compounds (21–30) were evaluated for in vitro inhibitory potential against cholinesterase enzymes. The results displayed that most of the derivatives were potent inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) with varying degree of IC50 values. The experimental results were further encouraged by molecular docking studies in order to explore their binding behavior with the active pocket of AChE and BChE enzymes. The experimental and theoretical results are in parallel with one another. 相似文献
77.
Neelam Sultan Irfan Ali Shazia Anwer Bukhari Shahid Mahmood Baig Muhammad Asif Muhammad Qasim Muhammad Imran Naseer Mahmood Rasool 《Genes & genomics.》2018,40(5):553-559
Retinitis pigmentosa (RP) is the most frequent genetically and clinically heterogeneous inherited retinal degeneration. To date, more than 80 genes have been identified that cause autosomal dominant, autosomal recessive and X linked RP. However, locus and allelic heterogeneity of RP has not been fully captured yet. This heterogeneity and lack of an accurate genotype phenotype correlation makes molecular dissection of the disease more difficult. The present study was designed to characterize the underlying pathogenic variants of RP in Pakistan. For this purpose, a large consanguineous family with RP phenotype showing autosomal recessive mode of inheritance was selected after a complete ophthalmological examination. Next generation sequencing was used for the identification of molecular determinant followed by Sanger-sequencing for confirmation. After sequence analysis a novel homozygous missense mutation, (c.602 C?>?T) in exon 4 of the RDH5 gene (MIM: 601617) was identified. This mutation resulted in substitution of phenyl alanine for serine at amino acid 201 (p.Ser201Phe) of the RDH5 gene. The same mutation was not detected in the 200 ethnically-matched control samples by Sanger sequencing. The identified mutant allele segregated in homozygous fashion in all the affected individuals of pedigree. Identification of this mutation reveals the allelic heterogeneity of RDH5 in patients with RP phenotype. The findings of this study demonstrate the clinical significance of next generation sequencing to understand the molecular basis of diseases and would help to reveal new proteins and their function in visual cycle will pave the way for early diagnosis, genetic counseling and better therapeutic inventions. 相似文献
78.
The air mycoflora of six indoor environments in Madras city (India) has been investigated by sampling air with an Andersen
sampler and a Burkard personal sampler. Forty-eight species assignable to 24 genera were recorded by Andersen sampler. Spores
belonging to 14 genera in addition toPenicillium andAspergillus were identified from Burkard trap slides. Species ofAspergillus, Penicillium, Mucor andRhizopus were most frequently isolated in considerable numbers. As a single genusAspergillus ranked first followed byPenicillium at some sites, andCladosporium at some other sites. The predominance ofPenicillium andAspergillus was also confirmed by Burkard trap data. Spores belonging toGanoderma, Nigrospora, Epicoccum, andTetraploa were recorded only by Burkard sampler, thereby suggesting the necessity of using two complimentary spore traps, cultural
and non-cultural, in any aerobiological investigation. 相似文献
79.
80.
Arsenic in groundwater and its health risk assessment in drinking water of Mailsi,Punjab, Pakistan 总被引:1,自引:0,他引:1
The present study was aimed at assessing drinking water quality regarding arsenic (As) and its impact on health from Mailsi (Punjab), Pakistan. Forty-four groundwater samples were collected from two sites, Sargana and Mailsi. Arsenic and other cations were determined by atomic absorption spectrophotometer, whereas the anions were determined either through titration or spectrophotometer. The results revealed that dominant anions were HCO3? and Cl?, Ca+2 was the dominant cation, and overall water chemistry of the area was CaMgHCO3? type. Arsenic concentrations were high, ranging from 11 to 828 µg/L that crossed the World Health Organization permissible limits. Likewise, higher SO4?2 concentrations ranging from 247 to 1053 mg/L were observed. The health risk index was higher in the Sargana site, which employed the differences in terms of higher Average Daily Dose, Hazard Quotient, and Carcinogenic Risk of arsenic, which is unsuitable for drinking purposes. The area seems to be at high risk due to arsenic pollution and wells have never been tested for arsenic concentrations earlier; therefore, necessary measures should be taken to test the wells with respect to arsenic. 相似文献