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991.
Arun Dev Sharma Prabhjot Kaur Gill Sukhdev Singh Bhullar Prabhjeet Singh 《World journal of microbiology & biotechnology》2005,21(6-7):929-932
Summary An extracellular inulinase (fructanase)-producing strain of Penicillium purpurogenum was isolated from the rhizosphere soil of chicory. Conidia of this selected strain were subjected to simultaneous treatment
with NTG–UV (N-methyl-N′-nitro-N-nitrosoguanidine and ultraviolet radiation) and EtBr–UV (Ethidium bromide–ultraviolet radiation). After mutagenesis, colonies
were screened and among them a few were selected to carry out the inulinase study, which showed a significantly higher inulinase
activity with higher I/S (inulin/sucrose) ratio in all the selected colonies, indicating enhancement of inulinase production
after mutagenic treatments in all the selected mutants. 相似文献
992.
Alexander R Balasundaram A Batchelor M Brookings D Crépy K Crabbe T Deltent MF Driessens F Gill A Harris S Hutchinson G Kulisa C Merriman M Mistry P Parton T Turner J Whitcombe I Wright S 《Bioorganic & medicinal chemistry letters》2008,18(15):4316-4320
4-(1,3-Thiazol-2-yl)morpholine derivatives have been identified as potent and selective inhibitors of phosphoinositide 3-kinase. The SAR data of selected examples are presented and the in vivo profiling of compound 18 is shown to demonstrate the utility of this class of compounds in xenograft models of tumor growth. 相似文献
993.
Beveridge TJ Gill KE Hanlon CA Porrino LJ 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2008,363(1507):3257-3266
Cocaine users display profound impairments in executive function. Of all the components of executive function, inhibition, or the ability to withhold responding, has been studied the most extensively and may be most impaired. Consistent with these deficits, evidence from imaging studies points to dysregulation in medial and ventromedial prefrontal cortices, areas activated during performance of inhibition tasks. Other aspects of executive function including updating, shifting and decision making are also deficient in cocaine users, and these deficits are paralleled by abnormalities in patterns of prefrontal cortical activation. The extent to which cocaine plays a role in these effects, however, is not certain, and cannot be determined solely on the basis of human studies. Investigations using a non-human primate model of increasing durations of cocaine exposure revealed that initially the effects of cocaine were restricted to ventromedial and orbital prefrontal cortices, but as exposure was extended the intensity and spatial extent of the effects on functional activity also expanded rostrally and laterally. Given the spatial overlap in prefrontal pathology between human and monkey studies, these longitudinal mapping studies in non-human primates provide a unique window of understanding into the dynamic neural changes that are occurring early in human cocaine abuse. 相似文献
994.
Dean C. Thorburn David L. Morgan Andrew J. Rowland Howard S. Gill Eric Paling 《Environmental Biology of Fishes》2008,83(2):139-145
The dwarf sawfish, Pristis clavata, was captured in marine waters of King Sound and estuarine waters of the Fitzroy, May and Robinson Rivers, in the Kimberley
region of Western Australia. Observations of sexual maturity and annuli present on vertebrae suggest that the estuarine waters
of at least the Fitzroy River act as a nursery for the species, where immature individuals may remain for at least 3 years.
The capture of immature individuals in excess of 2,330 mm TL during the current study in addition to Peverell’s (Peverell
in Environ Biol Fishes 73:391–402, 2005) record of a mature male measuring 3,060 mm TL implies that the species may attain
far greater lengths than previously reported and that the common name may not be entirely appropriate. In contrast to the
sympatric freshwater sawfish Pristis microdon, the number of rostral teeth of individual P. clavata can not be used to differentiate males from females, with both sexes possessing an average of 42 rostral teeth. 相似文献
995.
Development and mapping of EST-derived simple sequence repeat markers for hexaploid wheat. 总被引:21,自引:0,他引:21
Ju-Kyung Yu Trevor M Dake Sukhwinder Singh David Benscher Wanlong Li Bikram Gill Mark E Sorrells 《Génome》2004,47(5):805-818
Expressed sequence tags (ESTs) are a valuable source of molecular markers. To enhance the resolution of an existing linkage map and to identify putative functional polymorphic gene loci in hexaploid wheat (Triticum aestivum L.), over 260,000 ESTs from 5 different grass species were analyzed and 5418 SSR-containing sequences were identified. Using sequence similarity analysis, 156 cross-species superclusters and 138 singletons were used to develop primer pairs, which were then tested on the genomic DNA of barley (Hordeum vulgare), maize (Zea mays), rice (Oryza sativa), and wheat. Three-hundred sixty-eight primer pairs produced PCR amplicons from at least one species and 227 primer pairs amplified DNA from two or more species. EST-SSR sequences containing dinucleotide motifs were significantly more polymorphic (74%) than those containing trinucleotides (56%), and polymorphism was similar for markers in both coding and 5' untranslated (UTR) regions. Out of 112 EST-SSR markers, 90 identified 149 loci that were integrated into a reference wheat genetic map. These loci were distributed on 19 of the 21 wheat chromosomes and were clustered in the distal chromosomal regions. Multiple-loci were detected by 39% of the primer pairs. Of the 90 mapped ESTs, putative functions for 22 were identified using BLASTX queries. In addition, 80 EST-SSR markers (104 loci) were located to chromosomes using nullisomic-tetrasomic lines. The enhanced map from this study provides a basis for comparative mapping using orthologous and PCR-based markers and for identification of expressed genes possibly affecting important traits in wheat. 相似文献
996.
997.
Pooria Gill Mostafa Ghalami Amir Ghaemi Nader Mosavari Hossein Abdul-Tehrani Majid Sadeghizadeh 《NanoBioTechnology》2008,4(1-4):28-35
A nanodiagnostic method using nucleic acid sequence-based amplification (NASBA) and gold nanoparticle probes (AuNP probes) was developed for colorimetric detection of Mycobacterium tuberculosis. The primers targeting 16S rRNA were used for the amplification of mycobacterial RNA by the isothermal NASBA process. The amplicons were hybridized with specific gold nanoparticle probes. The RNA–DNA hybrids were colorimetrically detected by the accumulation of gold nanoparticles. Using this method, 10 CFU ml?1 of M. tuberculosis was detected within less than 1 h. Results obtained from the clinical specimens showed 94.7% and 96% sensitivity and specificity, respectively. No interference was encountered in the amplification and detection of M. tuberculosis in the presence of non-target bacteria, confirming the specificity of the method. 相似文献
998.
Wound healing is a dynamic process that involves a coordinated response of many cell types representing distinct tissue compartments and is fundamentally similar among tissue types. Among the many gene products that are essential for restoration of normal tissue architecture, several members of the matrix metalloproteinase (MMP) family function as positive and, at times, negative regulators of repair processes. MMPs were initially thought to only function in the resolution phase of wound healing, particularly during scar resorption; however, recent evidence suggests that they also influence other wound-healing responses, such as inflammation and re-epithelialization. In this review, we discuss what is currently known about the function of MMPs in wound healing and will provide suggestions for future research directions. 相似文献
999.
Glaister M Howatson G Pattison JR McInnes G 《Journal of strength and conditioning research / National Strength & Conditioning Association》2008,22(5):1597-1601
The ability to repeatedly produce a high-power output or sprint speed is a key fitness component of most field and court sports. The aim of this study was to evaluate the validity and reliability of eight different approaches to quantify this parameter in tests of multiple-sprint performance. Ten physically active men completed two trials of each of two multiple-sprint running protocols with contrasting recovery periods. Protocol 1 consisted of 12 x 30-m sprints repeated every 35 seconds; protocol 2 consisted of 12 x 30-m sprints repeated every 65 seconds. All testing was performed in an indoor sports facility, and sprint times were recorded using twin-beam photocells. All but one of the formulae showed good construct validity, as evidenced by similar within-protocol fatigue scores. However, the assumptions on which many of the formulae were based, combined with poor or inconsistent test-retest reliability (coefficient of variation range: 0.8-145.7%; intraclass correlation coefficient range: 0.09-0.75), suggested many problems regarding logical validity. In line with previous research, the results support the percentage decrement calculation as the most valid and reliable method of quantifying fatigue in tests of multiple-sprint performance. 相似文献
1000.
Classic strain engineering methods have previously been limited by the low-throughput of conventional sequencing technology. Here, we applied a new genomics technology, scalar analysis of library enrichments (SCALEs), to measure >3 million Escherichia coli genomic library clone enrichment patterns resulting from growth selections employing three aspartic-acid anti-metabolites. Our objective was to assess the extent to which access to genome-scale enrichment patterns would provide strain-engineering insights not reasonably accessible through the use of conventional sequencing. We determined that the SCALEs method identified a surprisingly large range of anti-metabolite tolerance regions (423, 865, or 909 regions for each of the three anti-metabolites) when compared to the number of regions (1-3 regions) indicated by conventional sequencing. Genome-scale methods uniquely enable the calculation of clone fitness values by providing concentration data for all clones within a genomic library before and after a period of selection. We observed that clone fitness values differ substantially from clone concentration values and that this is due to differences in overall clone fitness distributions for each selection. Finally, we show that many of the clones of highest fitness overlapped across all selections, suggesting that inhibition of aspartate metabolism, as opposed to specific inhibited enzymes, dominated each selection. Our follow up studies confirmed our observed growth phenotypes and showed that intracellular amino-acid levels were also altered in several of the identified clones. These results demonstrate that genome-scale methods, such as SCALEs, can be used to dramatically improve understanding of classic strain engineering approaches. 相似文献