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排序方式: 共有351条查询结果,搜索用时 15 毫秒
101.
Arndt JW Schwarzenbacher R Page R Abdubek P Ambing E Biorac T Canaves JM Chiu HJ Dai X Deacon AM DiDonato M Elsliger MA Godzik A Grittini C Grzechnik SK Hale J Hampton E Han GW Haugen J Hornsby M Klock HE Koesema E Kreusch A Kuhn P Jaroszewski L Lesley SA Levin I McMullan D McPhillips TM Miller MD Morse A Moy K Nigoghossian E Ouyang J Peti WS Quijano K Reyes R Sims E Spraggon G Stevens RC van den Bedem H Velasquez J Vincent J von Delft F Wang X West B White A Wolf G Xu Q Zagnitko O Hodgson KO 《Proteins》2005,58(3):755-758
102.
A total of 27 maize-based products destined for human consumption were collected from retail outlets within the city of Glasgow
in the UK and were analysed for the presence of aflatoxins using immunoaftinity column chromatography with fluorescence detection
and for fumonisins by competitive ELISA. Aflatoxins were detected at a trace level below 4 in eight (30%) of the 27 samples
tested, no sample contained aflatoxins at a high level although one sample of sweetcorn did contain aflatoxins at a level
of 5-10 Fumonisins were detected in eight (30%) of the samples at levels from 1 to 8mgkg-1 and a further eight samples contained fumonisin at a level below 1 mgkg-1 but above the detectable level. The highest concentration of fumonisins was found in a sample of fine corn meal at 8-12mgkg-1. 相似文献
103.
104.
Protein domains are generally thought to correspond to units of evolution. New research raises questions about how such domains are defined with bioinformatics tools and sheds light on how evolution has enabled partial domains to be viable.With the rapid expansion in the number of determined protein sequences - over 92 million in UniProt in March 2015 - an ever-increasing number of biologists are using bioinformatics tools for annotation of these sequences. One widely used strategy is to identify occurrences of Pfam families within the sequence of interest [1]. A Pfam family is a multiple sequence alignment of the occurrences of a particular domain both in different species and in different regions of the same protein. The concept underpinning Pfam is that proteins typically comprise one or more domains (regions), each of which is an evolutionary unit that generally has a well-defined biological function. A significant sequence similarity between a query protein and a Pfam family provides the basis for annotations. Two recent articles [2,3] in Genome Biology evaluate the implications of having the query sequence only matching part of a Pfam family, which is an intriguing finding, given that a Pfam family is considered to be an evolutionary unit. 相似文献
105.
Morten Nilsen Asima Lokmic Inga Leena Angell Karin C. Ldrup Carlsen Kai-Hkon Carlsen Guttorm Haugen Gunilla Hedlin Christine Monceyron Jonassen Benjamin J. Marsland Bjrn Nordlund Eva Maria Rehbinder Carina Madelen Saunders Hvard O. Skjerven Lars Snipen Anne Cathrine Staff Cilla Sderhll Riyas Vettukattil Knut Rudi 《Applied and environmental microbiology》2021,87(6)
106.
Haugen F Labori KJ Noreng HJ Buanes T Iversen PO Drevon CA 《Archives of physiology and biochemistry》2011,117(2):78-87
Loss of adipose tissue in patients with pancreatic cancer may involve altered gene expression. Peri-operative mRNA levels of 44 genes were analysed by RT-PCR in intra-abdominal (IAAT) and subcutaneous adipose tissue (SCAT) sampled from pancreatic ductal adenocarcinoma (PDAC) patients undergoing tumour resection (n?=?20), and control patients without cancer (n?=?11). Peri- and post-operative IAAT and SCAT masses were measured by computerized tomography. PDAC patients displayed 2.6- and 1.7-fold higher Zn-α2-glycoprotein (AZGP1) mRNA levels than controls in IAAT and SCAT, respectively (P?0.01), but expression was not correlated with post-operative changes in fat masses. IAAT mass changes correlated with genes in lipid metabolism, inflammation and apoptosis: e.g. stearoyl-Coenzyme A desaturase 1 (SCD), tumour necrosis factor (TNF) and chemokine (C-C motif) ligand 2 (CCL2; MCP-1). Patients with PDAC displayed increased AZGP1 mRNA levels in both IAAT and SCAT, but expression of other genes may predict IAAT loss. 相似文献
107.
Rainey PB Beaumont HJ Ferguson GC Gallie J Kost C Libby E Zhang XX 《Microbial cell factories》2011,10(Z1):S14
Stochastic phenotype switching - or bet hedging - is a pervasive feature of living systems and common in bacteria that experience fluctuating (unpredictable) environmental conditions. Under such conditions, the capacity to generate variable offspring spreads the risk of being maladapted in the present environment, against offspring likely to have some chance of survival in the future. While a rich subject for theoretical studies, little is known about the selective causes responsible for the evolutionary emergence of stochastic phenotype switching. Here we review recent work - both theoretical and experimental - that sheds light on ecological factors that favour switching types over non-switching types. Of particular relevance is an experiment that provided evidence for an adaptive origin of stochastic phenotype switching by subjecting bacterial populations to a selective regime that mimicked essential features of the host immune response. Central to the emergence of switching types was frequent imposition of 'exclusion rules' and 'population bottlenecks' - two complementary faces of frequency dependent selection. While features of the immune response, exclusion rules and bottlenecks are likely to operate in many natural environments. Together these factors define a set of selective conditions relevant to the evolution of stochastic switching, including antigenic variation and bacterial persistence. 相似文献
108.
Hand osteoarthritis (OA) is very frequent in middle-aged and older women and men in the general population. Currently, owing
to high feasibility and low costs, conventional radiography (CR) is the method of choice for evaluation of hand OA. CR provides
a two-dimensional picture of bony changes, such as osteophytes, erosions, cysts, and sclerosis, and joint space narrowing
as an indirect measure of cartilage loss. There are several standardized scoring methods for evaluation of radiographic hand
OA. The scales have shown similar reliability, validity, and sensitivity to change, and no conclusion about the preferred
instrument has been drawn. Patients with hand OA may experience pain, stiffness, and physical disability, but the associations
between radiographic findings and clinical symptoms are weak to moderate and vary across studies. OA is, indeed, recognized
to involve the whole joint, and modern imaging techniques such as ultrasound (US) and magnetic resonance imaging (MRI) could
be valuable tools for better evaluation of hand OA. Standardized scoring methods have been proposed for both modalities. Several
studies have examined the validity of US features in hand OA, whereas knowledge of the validity of MRI is more limited. However,
both synovitis (detected by either US or MRI) and MRI-defined bone marrow lesions have been associated with pain, indicating
that treatment of inflammation is important for pain management in hand OA. Both US and MRI have shown better sensitivity
than CR in detection of erosions, and this may indicate that erosive hand OA may be more common than previously thought. 相似文献
109.
Stoats are significant predators of native fauna in New Zealand. They occur in many habitat types and consume a wide range of prey. The diet of stoats in the Tasman River, South Canterbury, was studied by analysis of scats and den contents. Analysis of 206 scats showed that stoats ate mainly lagomorphs, birds and invertebrates. Minor components included mice, lizards, fish and hedgehogs. Stoats ate more birds in spring than in autumn, and female stoats ate more invertebrates than did males. The contents of 219 dens collected in the same area at the same time provided further information. Birds and lagomorphs occurred at high frequency in dens, and other components were minor. Remains in dens were larger than in scats and allowed identification of many more prey items to species level. Den contents revealed a potentially substantial impact of stoats on threatened shorebirds locally; this impact was not detected by analysis of scats. 相似文献
110.
Cecilie Totland Ming Ying Mette Haugen Kibret Mazengia Anette Storstein Jan Aarseth Aurora Martinez Christian Vedeler 《Cancer immunology, immunotherapy : CII》2013,62(8):1393-1396
Onconeural antibodies are important in the detection of paraneoplastic neurological syndromes (PNS). The avidity of Hu, Yo, and CRMP5 antibodies from 100 patients was determined by immunoprecipitation (IP), and 13 of the Yo positive sera were also tested by surface plasmon resonance (SPR). There was a significant association between the results from IP and SPR. Yo antibodies had higher avidity than Hu and CRMP5 antibodies, and both high- and low-avidity antibodies were associated with tumors and PNS. High-avidity Yo antibodies were mainly associated with ovarian cancer, whereas high-avidity Hu and CRMP5 antibodies were mainly associated with small-cell lung cancer. Low-avidity CRMP5 and Yo antibodies were less often detected by a commercial line blot than high-avidity antibodies. The failure to detect low-avidity onconeural antibodies may result in under diagnosis of PNS. 相似文献