共查询到20条相似文献,搜索用时 31 毫秒
1.
Background
The cationic peptide antibiotic polymyxin has recently been reevaluated in the treatment of severe infections caused by gram negative bacteria. 相似文献2.
Stéphanie Jaubert-Possamai Gaël Le Trionnaire Joël Bonhomme Georges K Christophides Claude Rispe Denis Tagu 《BMC biotechnology》2007,7(1):63
Background
RNA interference (RNAi) is a powerful method to inhibit gene expression in a sequence specific manner. 相似文献3.
Background
H-NS regulates the acid stress resistance. The present study aimed to characterize the H-NS-dependent cascade governing the acid stress resistance pathways and to define the interplay between the different regulators. 相似文献4.
Background
In protozoa, the identification of preserved motifs by comparative genomics is often impeded by difficulties to generate reliable alignments for non-coding sequences. Moreover, the evolutionary dynamics of regulatory elements in 3' untranslated regions (both in protozoa and metazoa) remains a virtually unexplored issue. 相似文献5.
Hongxing Sun Guangzhi Xu Hongdan Zhan Huan Chen Zongtao Sun Bing Tian Yuejin Hua 《BMC microbiology》2010,10(1):319
Background
Deinococcus radiodurans accumulates high levels of manganese ions, and this is believed to be correlated with the radiation resistance ability of this microorganism. However, the maintenance of manganese ion homeostasis in D. radiodurans remains to be investigated. 相似文献6.
Non‐destructive allometric estimates of above‐ground and below‐ground biomass of high‐mountain vegetation in the Andes
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Aim
Studies that monitor high‐mountain vegetation, such as paramo grasslands in the Andes, lack non‐destructive biomass estimation methods. We aimed to develop and apply allometric models for above‐ground, below‐ground and total biomass of paramo plants.Location
The paramo of southern Colombia between 1°09′N and 077°50′W, at 3,400 and 3,700 m a.s.l.Methods
We established 61 1‐m2 plots at random locations, excluding disturbed, inaccessible and peat bog areas. We measured heights and basal diameters of all vascular plants in these plots and classified them into seven growth forms. Near each plot, we sampled the biomass from plants of abundant genera, after having measured their height and basal diameter. Hence, we measured the biomass of 476 plants (allometric set). For each growth form we applied power‐law functions to develop allometric models of biomass against basal diameter, height, height x basal diameter and height × basal area. The best models were selected using AICc weights. Using the observed and predicted plant biomass of the allometric set we calculated absolute percentage errors using cross‐validation. The biomass of a plot was estimated by summing the predicted biomass of all plants in a plot. Confidence limits around these sums were calculated by bootstrapping.Results
For groups of <20 plants the biomass predictions yielded large (>15%) errors. Applying groups that resembled the 1‐m2 plots in density and composition, the errors for above‐ground and total biomass estimates were <15%. Across all plots, we obtained an above‐ground, below‐ground and total plot biomass of 329 ± 190, 743 ± 486 and 1011 ± 627 g/m2 (mean ± SD), respectively. These values were within the range of biomass estimates obtained destructively in the tropical Andes.Conclusions
In new applications, if target vegetation samples are similar regarding growth forms and genera to our allometric set, their biomass might be predicted applying our equations, provided they contain at least 50–100 plants. In other situations, we would recommend gathering additional biomass measurements from local plants to evaluate new regression equations. 相似文献7.
Jens Bo Andersen Bent B Roldgaard Bjarke Bak Christensen Tine Rask Licht 《BMC microbiology》2007,7(1):55
Background
Listeria monocytogenes has been implicated in several food borne outbreaks as well as sporadic cases of disease. Increased understanding of the biology of this organism is important in the prevention of food borne listeriosis. 相似文献8.
Daniel B Sloan Andrew J Alverson Helena Štorchová Jeffrey D Palmer Douglas R Taylor 《BMC evolutionary biology》2010,10(1):274
Background
Mitochondrial gene loss and functional transfer to the nucleus is an ongoing process in many lineages of plants, resulting in substantial variation across species in mitochondrial gene content. The Caryophyllaceae represents one lineage that has experienced a particularly high rate of mitochondrial gene loss relative to other angiosperms. 相似文献9.
Andrzej Piekarowicz Aneta Kłyż Michał Majchrzak Monika Adamczyk-Popławska Timothy K Maugel Daniel C Stein 《BMC microbiology》2007,7(1):66
Background
Bioinformatic analysis of the genome sequence of Neisseria gonorrhoeae revealed the presence of nine probable prophage islands. The distribution, conservation and function of many of these sequences, and their ability to produce bacteriophage particles are unknown. 相似文献10.
Telomere length determined by the fluorescence in situ hybridisation distinguishes malignant and benign cells in cytological specimens
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Y. Matsuda A. Suzuki S. Esaka Y. Hamashima M. Imaizumi M. Kinoshita H. Shirahata Y. Kiso H. Kojima M. Matsukawa Y. Fujii N. Ishikawa J. Aida K. Takubo T. Ishiwata M. Nishimura T. Arai 《Cytopathology》2018,29(3):262-266
Background
Telomeres are tandem repeats of TTAGGG at the end of eukaryotic chromosomes that play a key role in preventing chromosomal instability. The aim of the present study is to determine telomere length using fluorescence in situ hybridisation (FISH) on cytological specimens.Methods
Aspiration samples (n = 41) were smeared on glass slides and used for FISH.Results
Telomere signal intensity was significantly lower in positive cases (cases with malignancy, n = 25) as compared to negative cases (cases without malignancy, n = 16), and the same was observed for centromere intensity. The difference in DAPI intensity was not statistically significant. The ratio of telomere to centromere intensity did not show a significant difference between positive and negative cases. There was no statistical difference in the signal intensities of aspiration samples from ascites or pleural effusion (n = 23) and endoscopic ultrasound‐guided FNA samples from the pancreas (n = 18).Conclusions
The present study revealed that telomere length can be used as an indicator to distinguish malignant and benign cells in cytological specimens. This novel approach may help improve diagnosis for cancer patients. 相似文献11.
Steven D Fleming Asgerally T Fazleabas Stephen C Bell 《Reproductive biology and endocrinology : RB&E》2008,6(1):6
Background
The purpose of this study was to examine the effect of insulin on expression and synthesis of IGFBP-1 and IGFBP-2 in the baboon endometrium in vitro. 相似文献12.
Background
Salt stress is one of the major abiotic stresses affecting plant growth and productivity. Vacuolar H+-pyrophosphatase (H+-PPase) genes play an important role in salt stress tolerance in multiple species. 相似文献13.
Background
The primary aim of this study was to obtain more knowledge about the occurrence of Cryptosporidium and Giardia in young dogs in Norway. 相似文献14.
Background
The role of centrioles in mitotic spindle function remains unclear. One approach to investigate mitotic centriole function is to ask whether mutation of centriole-associated proteins can cause genomic instability. 相似文献15.
Ya-Nan Gong Wei-Wei Li Jiang-Ling Sun Fei Ren Lin He Hui Jiang Qun Wang 《BMC molecular biology》2010,11(1):71
Background
Fatty acid-binding proteins (FABPs), small cytosolic proteins that function in the uptake and utilization of fatty acids, have been extensively studied in higher vertebrates while invertebrates have received little attention despite similar nutritional requirements during periods of reproductive activity. 相似文献16.
Background
After amputation of the Xenopus tadpole tail, a functionally competent new tail is regenerated. It contains spinal cord, notochord and muscle, each of which has previously been shown to derive from the corresponding tissue in the stump. The regeneration of the neural crest derivatives has not previously been examined and is described in this paper. 相似文献17.
Background
The paca is a South American rodent with potential as a commercial food animal. We examined paca placenta as part of a wider effort to understand the reproductive biology of this species. 相似文献18.
19.
Background
During early differentiation of Dictyostelium the attractant cAMP is released periodically to induce aggregation of the cells. Here we pursue the question whether pulsatile cAMP signaling is coupled to a basic Ca2+-oscillation. 相似文献20.
Volkan Yıldırım Servet Özcan Dörte Becher Knut Büttner Michael Hecker Gülay Özcengiz 《Proteome science》2011,9(1):12