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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.
Fushi Wen Ho Hyung Woo Elizabeth A. Pierson Toril D. Eldhuset C. G. Fossdal N. E. Nagy Martha C. Hawes 《Plant Molecular Biology Reporter》2009,27(1):58-68
Root cap development in cereals and legumes is self-regulated by a repressor that accumulates in the extracellular environment,
and immersing the root tip into water results in renewed cap development. By exploiting this phenomenon, root cap mitosis
and differentiation can be synchronously induced among populations. In Pisum sativum L., messenger RNA (mRNA) differential display revealed changes in expression of approximately 1% of the sample mRNA population
within minutes of induced cap turnover. This profile changes sequentially over a period of 30 min, then stabilizes. Microarray
analysis of Medicago truncatula root caps confirmed changes in expression of approximately 1% of the target population, within minutes. A cell specific marker
for cap turnover exhibited the same temporal and spatial expression profile in the gymnosperm species Norway spruce (Picea abies) as in pea. Induced cap development provides a means to profile cell-specific gene expression among phylogenetically diverse
species from the early moments of mitosis and cellular differentiation. 相似文献
3.
Toril Synnøve Jenssen 《Visual Anthropology: Published in cooperation with the Commission on Visual Anthropology》2013,26(4):291-308
ABSTRACT The use of film as a tool in anthropological fieldwork is a challenge to traditional ways of thinking about scientific research. Nevertheless, documentary filming of the informants in their own context has proved to be an interesting supplement in the exploration of what the anthropological research field actually covers. Furthermore, film work confronts the researchers with aesthetic aspects of mediation that have not been epistemically well attended to within social science. This article highlights pivotal problems in the professional no-man's-land where visual culture studies take place, as exemplified by the film Cool and Crazy. 相似文献
4.
Experimental warming increases herbivory by leaf‐chewing insects in an alpine plant community
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Tone Birkemoe Saskia Bergmann Toril E. Hasle Kari Klanderud 《Ecology and evolution》2016,6(19):6955-6962
Climate warming is predicted to affect species and trophic interactions worldwide, and alpine ecosystems are expected to be especially sensitive to changes. In this study, we used two ongoing climate warming (open‐top chambers) experiments at Finse, southern Norway, to examine whether warming had an effect on herbivory by leaf‐chewing insects in an alpine Dryas heath community. We recorded feeding marks on the most common vascular plant species in warmed and control plots at two experimental sites at different elevations and carried out a brief inventory of insect herbivores. Experimental warming increased herbivory on Dryas octopetala and Bistorta vivipara. Dryas octopetala also experienced increased herbivory at the lower and warmer site, indicating an overall positive effect of warming, whereas B. vivipara experienced an increased herbivory at the colder and higher site indicating a mixed effect of warming. The Lepidoptera Zygaena exulans and Sympistis nigrita were the two most common leaf‐chewing insects in the Dryas heath. Based on the observed patterns of herbivory, the insects life cycles and feeding preferences, we argue that Z. exulans is the most important herbivore on B. vivipara, and S. nigrita the most important herbivore on D. octopetala. We conclude that if the degree of insect herbivory increases in a warmer world, as suggested by this study and others, complex interactions between plants, insects, and site‐specific conditions make it hard to predict overall effects on plant communities. 相似文献
5.
Zan Strabac Toril Aalberg Anders Todal Jenssen Marko Valenta 《Ethnic and racial studies》2016,39(15):2665-2682
Immigrant women are a particularly vulnerable part of the immigrant population. In this paper we analyse negative attitudes towards immigrant women in Norway. We focus on immigrant women’s formal job qualifications, their religious background and wearing of hijab – the headscarf sometimes used by Muslim women. Using survey-embedded experiments we are able to analyse the net effects on attitudes of job qualifications, Islamic religious background and the hijab. The results show that native population frequently has more negative views of Muslim women who wear a hijab. The negative effects of a hijab do not seem to be strongly reduced if a woman wearing it has higher education. With a single exception, the results also show that Muslim background in itself (i.e. without the hijab) does not have any strong effect on attitudes of the native population towards immigrant women. 相似文献
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No ligand has hitherto been designated for the Eph receptor tyrosine kinase family member, EphB6. Here, expression of an EphB6 ligand in the pro-B leukemic cell line, Reh, is demonstrated by binding of soluble EphB6-Fc fusion protein to the Reh cells. The ligand belongs to the subgroup of membrane spanning ligands, as suggested by the fact that phosphatidylinositol-specific phospholipase C treatment did not abrogate binding of EphB6-Fc. Two transmembrane Eph receptor ligands, ephrin-B1 and ephrin-B2, were identified in Reh cells. Analysis of EphB6-Fc fusion protein binding to ephrin-B1 or ephrin-B2 transfected COS cells revealed a high-affinity saturable binding between EphB6-Fc and ephrin-B2, but not with ephrin-B1. In mice, EphB6 has previously been shown to be expressed in thymus. Here, we show expression of EphB6 in human thymus, as well as the expression of ephrin-B2 in both human and mouse thymus. We conclude that ephrin-B2 may be a physiological ligand for the EphB6 receptor. 相似文献
8.
Roman Gebauer Daniel Volaík Josef Urban Isabella Brja Nina Elisabeth Nagy Toril Drabls Eldhuset Paal Krokene 《Ecology and evolution》2015,5(21):4989-4998
Predicted increases in the frequency and duration of drought are expected to negatively affect tree vitality, but we know little about how water shortage will influence needle anatomy and thereby the trees’ photosynthetic and hydraulic capacity. In this study, we evaluated anatomical changes in sun and shade needles of 20‐year‐old Norway spruce trees exposed to artificial drought stress. Canopy position was found to be important for needle structure, as sun needles had significantly higher values than shade needles for all anatomical traits (i.e., cross‐sectional needle area, number of tracheids in needle, needle hydraulic conductivity, and tracheid lumen area), except proportion of xylem area per cross‐sectional needle area. In sun needles, drought reduced all trait values by 10–40%, whereas in shade needles, only tracheid maximum diameter was reduced by drought. Due to the relatively weaker response of shade needles than sun needles in drought‐stressed trees, the difference between the two needle types was reduced by 25% in the drought‐stressed trees compared to the control trees. The observed changes in needle anatomy provide new understanding of how Norway spruce adapts to drought stress and may improve predictions of how forests will respond to global climate change. 相似文献
9.
Alexandr N. Simonov Jessica K. Holien Joyee Chun In Yeung Ann D. Nguyen C. Jo Corbin Jie Zheng Vladimir L. Kuznetsov Richard J. Auchus Alan J. Conley Alan M. Bond Michael W. Parker Raymond J. Rodgers Lisandra L. Martin 《PloS one》2015,10(11)
Cytochrome P450c17 (P450 17A1, CYP17A1) is a critical enzyme in the synthesis of androgens and is now a target enzyme for the treatment of prostate cancer. Cytochrome P450c17 can exhibit either one or two physiological enzymatic activities differentially regulated by cytochrome b5. How this is achieved remains unknown. Here, comprehensive in silico, in vivo and in vitro analyses were undertaken. Fluorescence Resonance Energy Transfer analysis showed close interactions within living cells between cytochrome P450c17 and cytochrome b5. In silico modeling identified the sites of interaction and confirmed that E48 and E49 residues in cytochrome b5 are essential for activity. Quartz crystal microbalance studies identified specific protein-protein interactions in a lipid membrane. Voltammetric analysis revealed that the wild type cytochrome b5, but not a mutated, E48G/E49G cyt b5, altered the kinetics of electron transfer between the electrode and the P450c17. We conclude that cytochrome b5 can influence the electronic conductivity of cytochrome P450c17 via allosteric, protein-protein interactions. 相似文献
10.
Crystal structure of human insulin‐regulated aminopeptidase with specificity for cyclic peptides
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Stefan J. Hermans David B. Ascher Nancy C. Hancock Jessica K. Holien Belinda J. Michell Siew Yeen Chai Craig J. Morton Michael W. Parker 《Protein science : a publication of the Protein Society》2015,24(2):190-199
Insulin‐regulated aminopeptidase (IRAP or oxytocinase) is a membrane‐bound zinc‐metallopeptidase that cleaves neuroactive peptides in the brain and produces memory enhancing effects when inhibited. We have determined the crystal structure of human IRAP revealing a closed, four domain arrangement with a large, mostly buried cavity abutting the active site. The structure reveals that the GAMEN exopeptidase loop adopts a very different conformation from other aminopeptidases, thus explaining IRAP's unique specificity for cyclic peptides such as oxytocin and vasopressin. Computational docking of a series of IRAP‐specific cognitive enhancers into the crystal structure provides a molecular basis for their structure–activity relationships and demonstrates that the structure will be a powerful tool in the development of new classes of cognitive enhancers for treating a variety of memory disorders such as Alzheimer's disease. 相似文献