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排序方式: 共有244条查询结果,搜索用时 15 毫秒
1.
David Ryberg Toril Tefre Steinar Øvrebø Vidar Skaug Lodve Stangeland Anne Naalsund Rita Bæra Anne-Lise Børresen Aage Haugen 《Human genetics》1990,86(1):40-44
Summary We have examined DNA restriction fragment length polymorphisms (RFLP) of the Ha-ras-1 gene in DNA from 118 lung cancer patients and 123 unaffected controls. When DNA samples were digested with MspI/ HpaII restriction endonucleases. Southern blot analysis demonstrated 4 common, 4 intermediate and 7 different rare alleles in the combined population after hybridization to the pGDa1 probe. Six of the rare alleles were unique for the lung cancer group and 1 rare allele for the control group. The frequency of rare alleles in lung cancer patients (10/236) was significantly different (P<0.01) from the control group (1/246). The lung cancer group also had a significantly lower frequency of the common 2.57 kb fragment than the controls (P<0.02). The results thus indicate that Ha-ras genotyping may be of value in lung cancer risk assessment. 相似文献
2.
Jacques Simard Dominique Bérubé Märten Sandberg Karl-Heinz Grzeschik Richard Gagné Vidar Hansson Tore Jahnsen 《Human genetics》1992,88(6):653-657
Summary A cDNA for the human catalytic subunit (C) of cAMP-dependent protein kinase (PKA) has been cloned from a testis cDNA library. In the present study, we have determined the chromosomal localization of this gene using a cDNA for C as a probe. Southern blot analysis of genomic DNA from human/mouse cell hybrids revealed that the presence or absence of a 20-kbXbaI fragment, which hybridized with the C probe, was concordant with the presence of human chromosome 1.In situ hybridization to metaphase chromosome confirmed the somatic cell hybrid data and regionally mapped the C gene of PKA to the p36 band on chromosome 1. 相似文献
3.
Kjetil Taskn Rigmor Solberg Ying Zhao Vidar Hansson Tore Jahnsen Michael J. Siciliano 《Genomics》1996,36(3):535
We have determined the chromosomal localization of the gene for the catalytic subunit Cα of cAMP-dependent protein kinase (locus PRKACA) to human chromosome 19 using polymerase chain reaction (PCR) and Southern blot analysis of two different somatic cell hybrid mapping panels. In addition, PCR analysis of a chromosome 19 mapping panel revealed the presence of a human Cα-specific amplification product only in cell lines containing the region 19p13.1 to 19q12. Finally, two-color fluorescencein situhybridization to metaphase chromosomes using the human Cα cDNA and human chromosome 19 inter-Alu-PCR product as probes localized the human Cα gene to chromosome region 19p13.1. 相似文献
4.
Prof. Dr. Mehmet Emin Duru Büşra Eroğlu Assoc. Prof. Dr. Gülsen Tel-Çayan Meltem Taş-Küçükaydın Dr. Selçuk Küçükaydın Dr. Fatih Çayan Prof. Dr. Özgür Ceylan 《化学与生物多样性》2023,20(6):e202300486
Sunflower honey (SH) is bright yellow, fragrant, pollen-flavoured, slightly herbaceous and has a unique taste. The present research aims to examine the enzyme inhibitory, antioxidant, anti-inflammatory, antimicrobial and anti-quorum sensing activities and phenolic compositions of 30 sunflower honeys (SHs) produced from several regions of Turkey with chemometric study. SAH from Samsun exhibited the best antioxidant activity in β-carotene linoleic acid (IC50: 7.33±0.17 mg/mL) and CUPRAC (A0.50: 4.94±0.13 mg/mL) assays, anti-urease activity (60.63±0.87 %) and anti-inflammatory activity against COX-1 (73.94±1.08 %) and COX-2 (44.96±0.85 %). SHs exhibited mild antimicrobial activity against the test microorganisms while they showed high quorum sensing inhibition zones measured in the range of 42–52 mm against the CV026 strain. The phenolic composition was determined by high performance liquid chromatography with diode array detection (HPLC-DAD) system and levulinic, gallic, p-hydroxybenzoic, vanillic and p-coumaric acids were identified in all studied SHs. The classification of SHs was performed the using PCA and HCA. This study revealed that phenolic compounds and biological properties are effective in classification of SHs according to their geographical origin. The results suggest that studied SHs could be valued as potential agents with versatile bioactivities in oxidative stress-related disease, microbial infections, inflammation, melanoma, and peptic ulcer. 相似文献
5.
Kate Layton‐Matthews Brage Bremset Hansen Vidar Grtan Eva Fuglei Maarten J. J. E. Loonen 《Global Change Biology》2020,26(2):642-657
Climate change is most rapid in the Arctic, posing both benefits and challenges for migratory herbivores. However, population‐dynamic responses to climate change are generally difficult to predict, due to concurrent changes in other trophic levels. Migratory species are also exposed to contrasting climate trends and density regimes over the annual cycle. Thus, determining how climate change impacts their population dynamics requires an understanding of how weather directly or indirectly (through trophic interactions and carryover effects) affects reproduction and survival across migratory stages, while accounting for density dependence. Here, we analyse the overall implications of climate change for a local non‐hunted population of high‐arctic Svalbard barnacle geese, Branta leucopsis, using 28 years of individual‐based data. By identifying the main drivers of reproductive stages (egg production, hatching and fledging) and age‐specific survival rates, we quantify their impact on population growth. Recent climate change in Svalbard enhanced egg production and hatching success through positive effects of advanced spring onset (snow melt) and warmer summers (i.e. earlier vegetation green‐up) respectively. Contrastingly, there was a strong temporal decline in fledging probability due to increased local abundance of the Arctic fox, the main predator. While weather during the non‐breeding season influenced geese through a positive effect of temperature (UK wintering grounds) on adult survival and a positive carryover effect of rainfall (spring stopover site in Norway) on egg production, these covariates showed no temporal trends. However, density‐dependent effects occurred throughout the annual cycle, and the steadily increasing total flyway population size caused negative trends in overwinter survival and carryover effects on egg production. The combination of density‐dependent processes and direct and indirect climate change effects across life history stages appeared to stabilize local population size. Our study emphasizes the need for holistic approaches when studying population‐dynamic responses to global change in migratory species. 相似文献
6.
Atle van Beelen Granlund Arnar Flatberg Ann E. ?stvik Ignat Drozdov Bj?rn I. Gustafsson Mark Kidd Vidar Beisvag Sverre H. Torp Helge L. Waldum Tom Christian Martinsen Jan Kristian Dam?s Terje Espevik Arne K. Sandvik 《PloS one》2013,8(2)
Background
In inflammatory bowel disease (IBD), genetic susceptibility together with environmental factors disturbs gut homeostasis producing chronic inflammation. The two main IBD subtypes are Ulcerative colitis (UC) and Crohn’s disease (CD). We present the to-date largest microarray gene expression study on IBD encompassing both inflamed and un-inflamed colonic tissue. A meta-analysis including all available, comparable data was used to explore important aspects of IBD inflammation, thereby validating consistent gene expression patterns.Methods
Colon pinch biopsies from IBD patients were analysed using Illumina whole genome gene expression technology. Differential expression (DE) was identified using LIMMA linear model in the R statistical computing environment. Results were enriched for gene ontology (GO) categories. Sets of genes encoding antimicrobial proteins (AMP) and proteins involved in T helper (Th) cell differentiation were used in the interpretation of the results. All available data sets were analysed using the same methods, and results were compared on a global and focused level as t-scores.Results
Gene expression in inflamed mucosa from UC and CD are remarkably similar. The meta-analysis confirmed this. The patterns of AMP and Th cell-related gene expression were also very similar, except for IL23A which was consistently higher expressed in UC than in CD. Un-inflamed tissue from patients demonstrated minimal differences from healthy controls.Conclusions
There is no difference in the Th subgroup involvement between UC and CD. Th1/Th17 related expression, with little Th2 differentiation, dominated both diseases. The different IL23A expression between UC and CD suggests an IBD subtype specific role. AMPs, previously little studied, are strongly overexpressed in IBD. The presented meta-analysis provides a sound background for further research on IBD pathobiology. 相似文献7.
Phosphoserine phosphatase (PSP) catalyzes the final and irreversible step of L‐serine synthesis by hydrolyzing phosphoserine to produce L ‐serine and inorganic phosphate. Developing a therapeutic drug that interferes with serine production is of great interest to regulate the pathogenicity of some bacteria and control D ‐serine levels in neurological diseases. We determined the crystal structure of PSP from the hyperthermophilic archaeon Thermococcus onnurineus at 1.8 Å resolution, revealing an NDSB ligand bound to a novel site that is located in a fissure between the catalytic domain and the CAP module. The structure shows a half‐open conformation of the CAP 1 module with a unique protruding loop of residues 150–155 that possesses a helical conformation in other structures of homologous PSPs. Activity assays indicate that the enzyme exhibits marginal PSP activity at low temperature but a sharp increase in the kcat/KM value, approximately 22 fold, when the temperature is increased. Structural and biochemical analyses suggest that the protruding loop in the active site might be an essential component for the regulation of the activity of PSP from hyperthermophilic T. onnurineus. Identification of this novel binding site distantly located from the catalytic site may be exploited for the development of effective therapeutic allosteric inhibitors against PSP activity. © Proteins 2013. © 2012 Wiley Periodicals, Inc. 相似文献
8.
9.
A single bout of exercise with high mechanical loading induces the expression of Cyr61/CCN1 and CTGF/CCN2 in human skeletal muscle. 总被引:1,自引:0,他引:1
Riikka Kivel? Heikki Kyr?l?inen Harri Sel?nne Paavo V Komi Heikki Kainulainen Veikko Vihko 《Journal of applied physiology》2007,103(4):1395-1401
High mechanical loading was hypothesized to induce the expression of angiogenic and/or lymphangiogenic extracellular matrix (ECM) proteins in skeletal muscle. Eight men performed a strenuous exercise protocol, which consisted of 100 unilateral maximal drop jumps followed by submaximal jumping until exhaustion. Muscle biopsies were taken 30 min and 48 h postexercise from the vastus lateralis muscle and analyzed for the following parameters: mRNA and protein expression of ECM-associated CCN proteins [cysteine-rich angiogenic protein 61 (Cyr61)/CCN1, connective tissue growth factor (CTGF)/CCN2], and mRNA expression of vascular endothelial growth factors (VEGFs) and hypoxia-inducible factor-1alpha. The mRNA expression of Cyr61 and CTGF increased 30 min after the exercise (14- and 2.5-fold, respectively; P < 0.001). Cyr61 remained elevated 48 h postexercise (threefold; P < 0.05). The mRNA levels of VEGF-A, VEGF-B, VEGF-C, VEGF-D, or hypoxia-inducible factor-1alpha did not change significantly at either 30 min or 48 h postexercise; however, the variation between subjects increased markedly in VEGF-A and VEGF-B mRNA. Cyr61 protein levels were higher at both 30 min and 48 h after the exercise compared with the control (P < 0.05). Cyr61 and CTGF proteins were localized to muscle fibers and the surrounding ECM by immunohistochemistry. Fast fibers stained more intensively than slow fibers. In conclusion, mechanical loading induces rapid expression of CCN proteins in human skeletal muscle. This may be one of the early mechanisms involved in skeletal muscle remodeling after exercise, since Cyr61 and CTGF regulate the expression of genes involved in angiogenesis and ECM remodeling. 相似文献
10.
Keskil IS Kemali Baykaner M Aricioğlu A Kaymaz M Uysal SS Ataoğlu OO Balabanli B Ercan S Ceviker N 《Prostaglandins, leukotrienes, and essential fatty acids》2004,71(1):7-11
Iloprost, a stable analogue of prostacyclin, was used to reverse the early period of vasoconstriction provoked by Endothelin-1 by administering into the rabbit basilar artery. We observed if this produced an effect on the central nervous system parenchyma mediated by free radical system. The red neurons were counted in brain stem sections stained with haematoxylin and eosin, while superoxide dismutase and malondialdehyde levels were measured in brain stem tissue samples as a marker of reactive oxygen metabolites; both 30 and 90 min after administration of either Endothelin-1 (0.25 ng) alone or Endothelin-1 followed by Iloprost (0.5 microg/kg) into the basilar artery. Endothelin-1 significantly increased the number of red neurons, while Iloprost significantly reduced them after 30 and 90 min. However, regarding the reactive oxygen metabolites; a similar reversing effect of Iloprost was not observed although superoxide dismutase levels were significantly decreased after Endothelin-1 infusion. 相似文献