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111.
Isolation and transcription profiling of purified uncultured human stromal stem cells: alteration of gene expression after in vitro cell culture 总被引:11,自引:0,他引:11 下载免费PDF全文
Boquest AC Shahdadfar A Frønsdal K Sigurjonsson O Tunheim SH Collas P Brinchmann JE 《Molecular biology of the cell》2005,16(3):1131-1141
112.
Jensen RB Jeppesen KA Vielwerth S Michaelsen KF Main KM Skakkebaek NE Juul A 《Hormone research》2005,63(1):15-21
BACKGROUND: The diagnosis of growth hormone deficiency (GHD) in infancy is difficult, and no specific cutoff value during GH provocative testing is recommended in early life. METHODS: Serum insulin-like growth factor I (IGF-I) and serum IGF-binding protein 3 (IGFBP-3) levels were evaluated as diagnostic markers of GHD. Measurements of IGF-I and IGFBP-3 during the 1st year of life were analyzed in 11 patients clinically suspected of having GHD (neonatal hypoglycemia, micropenis, or evidence of other pituitary hormone deficiencies), in whom the diagnosis was later verified. A prospective cohort of 51 healthy infants served as controls. RESULTS: The sensitivity of IGF-I as a diagnostic marker of GHD was 90% (10 out of 11 patients) with a cutoff value of -2 standard deviations (SD), and the sensitivity of IGFBP-3 measurements was 81% (9 out of 11 patients) with a cutoff value below -2 SD. One patient had serial measurements before initiation of GH treatment where the IGF-I was fluctuating (3 of 6 slightly above -2 SD), whereas all IGFBP-3 measurements were below -2 SD. CONCLUSIONS: The IGF-I had a high sensitivity in detecting infants with GHD. The combination of IGF-I and IGFBP-3 increased the diagnostic sensitivity. We speculate that assessment of IGF-I and IGFBP-3 may add diagnostic value in infants suspected of having GHD and furthermore that values below -2 SD are highly suggestive of GHD. 相似文献
113.
Strøbaek D Teuber L Jørgensen TD Ahring PK Kjaer K Hansen RS Olesen SP Christophersen P Skaaning-Jensen B 《Biochimica et biophysica acta》2004,1665(1-2):1-5
We have identified and characterized the compound NS309 (6,7-dichloro-1H-indole-2,3-dione 3-oxime) as a potent activator of human Ca2+ -activated K+ channels of SK and IK types, whereas it is devoid of effect on BK type channels. IK- and SK-channels have previously been reported to be activated by the benzimidazolinone, 1-EBIO and more potently by its dichloronated-analogue, DC-EBIO. NS309 is at least 1000 times more potent than 1-EBIO and at least 30 times more potent than DC-EBIO when the compounds are compared on the same cell. 相似文献
114.
Lise Ruffino Tarja Oksanen Katrine S. Hoset Maria Tuomi Lauri Oksanen Erkki Korpimäki Amandine Bugli Keith A. Hobson Bernt Johansen Aurelia Mäkynen 《Ecography》2016,39(9):871-883
Spatial variation in the strength of trophic cascades in arctic tundra has been related to flows of subsidies across ecosystem boundaries. Here, we ask whether the input of marine subsidies in tundra systems would cause spatial variation in the strength of rodent–plant interactions between coastal areas, where predators have access to marine‐derived resources, and non‐subsidized inland areas of northern Fennoscandia. We present a detailed evaluation of predator–rodent–vegetation interactions along a coast‐inland gradient, during the 2011 rodent outbreak and the two following decline years, by using direct assessments of rodent impacts and tracing of marine‐derived nutrients in the food web. Our results revealed that the main rodent predator during summer, the long‐tailed jaeger Stercorarius longicaudus, did not benefit from marine resources while breeding (relative dietary proportion in chicks’ diet = 0–3%). Contrary to this pattern, parasitic jaegers S. parasiticus, bred exclusively near the coast and preyed effectively on both marine resources (41% of chicks’ diet) and rodents (12%). Mammalian predators also showed a higher activity during winter near the coast. Despite overall higher predator numbers, no evidence was found for lower rodent population growth rates during the three monitoring summers and for weaker rodent grazing impacts in the coastal area. Instead, we documented pronounced damages caused by lemmings and voles on bryophytes and vascular plants, especially dwarf shrubs (e.g. Vaccinum myrtillus) all along the coast–inland gradient. Taken together, our results did not support the hypothesis that marine subsidies would trigger a trophic cascade in coastal tundra areas of northern Fennoscandia during a major rodent outbreak, probably due to a relatively low diversity of marine‐subsidized predators in the region. Comparative observational and experimental studies at large spatial scales in various arctic regions are absolutely necessary for a better understanding of factors causing regional variations in the functioning of arctic food webs. 相似文献
115.
Martin Oliver Macnaughton Katrine Worsaae Danny Eibye‐Jacobsen 《Journal of morphology》2010,271(3):324-339
Detailed scanning electron microscopy of jaws within the genus Ophryotrocha (Dorvilleidae, Annelida) was performed on 871 jaw parts. The investigations resulted in new understandings of the ontogeny and jaw morphology and have systematic implications for the family. Five species in the genus (Ophryotrocha alborana, O. diadema, O. gracilis, O. hartmanni, and O. labronica pacifica) were kept in culture, and the development of the jaws was studied by sampling throughout their life history. Ophryotrocha species have mandibular plates that remain the same throughout ontogeny, whereas the posterior shafts elongate. Both mandibular plate morphology and shaft ontogeny have species‐specific distinctions. In Ophryotrocha, the maxillae can be assigned to three to four distinct types, which are replaced by moulting. The maxillary morphology and developmental stages at which moults occur are species specific, although with broad intervals. A redefinition is given for some of the basic jaw elements, and new homologies are proposed for structures that are also present across other dorvilleid taxa. J. Morphol. 2010. © 2009 Wiley‐Liss, Inc. 相似文献
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117.
Anders Bergstr?m Thomas Hjort Skov Martin Iain Bahl Henrik Munch Roager Line Brinch Christensen Katrine Tschentscher Ejlerskov Christian M?lgaard Kim F. Michaelsen Tine Rask Licht 《Applied and environmental microbiology》2014,80(9):2889-2900
Fecal samples were obtained from a cohort of 330 healthy Danish infants at 9, 18, and 36 months after birth, enabling characterization of interbacterial relationships by use of quantitative PCR targeting 31 selected bacterial 16S rRNA gene targets representing different phylogenetic levels. Nutritional parameters and measures of growth and body composition were determined and investigated in relation to the observed development in microbiota composition. We found that significant changes in the gut microbiota occurred, particularly from age 9 to 18 months, when cessation of breastfeeding and introduction of a complementary feeding induce replacement of a microbiota characterized by lactobacilli, bifidobacteria, and Enterobacteriaceae with a microbiota dominated by Clostridium spp. and Bacteroides spp. Classification of samples by a proxy enterotype based on the relative levels of Bacteroides spp. and Prevotella spp. showed that enterotype establishment occurs between 9 and 36 months. Thirty percent of the individuals shifted enterotype between 18 and 36 months. The composition of the microbiota was most pronouncedly influenced by the time of cessation of breastfeeding. From 9 to 18 months, a positive correlation was observed between the increase in body mass index and the increase of the short-chain-fatty-acid-producing clostridia, the Clostridum leptum group, and Eubacterium hallii. Considering previously established positive associations between rapid infant weight gain, early breastfeeding discontinuation, and later-life obesity, the corresponding microbial findings seen here warrant attention. 相似文献
118.
Katrine Meisner Peter Sunde Kevin Kuhlmann Clausen Preben Clausen Casper Cæsar Fælled Marie Hoelgaard 《Acta theriologica》2014,59(3):377-389
We investigated diet composition, habitat selection and spatial behaviour of the red fox (Vulpes vulpes) in relation to the availability of wader nests in a coastal polder area in southwest Denmark. The predatory role of the red fox in wet grassland ecosystems has profound implications for conservation status of declining populations of grassland breeding waders. However, few studies have focussed on the foraging ecology and behaviour of the red fox in these landscapes. Faecal analyses revealed that fox diet consisted of birds (43 % of prey remains?/?32 % of biomass), rodents (39 %?/?21 %), sheep (mainly as carrion, 14 %?/?41 %) and lagomorphs (4 %?/?7 %). Charadriiformes (including waders) comprised 3–12 % of prey remains throughout the year. Telemetry data and spotlight counts indicated that foxes did not select areas with high densities of breeding waders, suggesting that foxes did not target wader nests while foraging. Foxes maintained stable home ranges throughout their lives, indicating that the area sustained a permanent fox population all year round. The population densities, estimated from spotlight surveys, were 0.74 visible foxes km?2 (95 % CI; 0.34–1.61) on the preferred breeding habitat for waders and 1.21 km?2 in other open habitats such as cultivated fields. Our results indicate that red fox predation on wader nests is incidental, consistent with the notion that red foxes are generalist predators that opportunistically subsist on many prey groups. 相似文献
119.
Catharina Steentoft Katrine T. Schjoldager Emiliano Cló Ulla Mandel Steven B. Levery Johannes W. Pedersen Knud Jensen Ola Blixt Henrik Clausen 《Glycoconjugate journal》2010,27(6):571-582
Auto-antibodies induced by cancer represent promising sensitive biomarkers and probes to identify immunotherapeutic targets
without immunological tolerance. Surprisingly few epitopes for such auto-antibodies have been identified to date. Recently,
a cancer-specific syngeneic murine monoclonal antibody 237, developed to a spontaneous murine fibrosarcoma, was shown to be
directed to murine podoplanin (OTS8) with truncated Tn O-glycans. Our understanding of such cancer-specific auto-antibodies
to truncated glycoforms of glycoproteins is limited. Here we have investigated immunogenicity of a chemoenzymatically produced
Tn-glycopeptide derived from the putative murine podoplanin O-glycopeptide epitope. We found that the Tn O-glycopeptide was
highly immunogenic in mice and produced a Tn-glycoform specific response with no reactivity against unglycosylated peptides
or the O-glycopeptide with extended O-glycan (STn and T glycoforms). The immunodominant epitope was strictly dependent on
the peptide sequence, required Tn at a specific single Thr residue (Thr77), and antibodies to the epitope were not found in naive mice. We further tested a Tn O-glycopeptide library derived from
human podoplanin by microarray analysis and demonstrated that the epitope was not conserved in man. We also tested human cancer
sera for potential auto-antibodies to similar epitopes, but did not detect such antibodies to the Tn-library of podoplanin.
The reagents and methods developed will be valuable for further studies of the nature and timing of induction of auto-antibodies
to distinct O-glycopeptide epitopes induced by cancer. The results demonstrate that truncated O-glycopeptides constitute highly
distinct antibody epitopes with great potential as targets for biomarkers and immunotherapeutics. 相似文献
120.
Jensen JK Malmendal A Schiøtt B Skeldal S Pedersen KE Celik L Nielsen NC Andreasen PA Wind T 《The Biochemical journal》2006,399(3):387-396
The functions of the serpin PAI-1 (plasminogen activator inhibitor-1) are based on molecular interactions with its target proteases uPA and tPA (urokinase-type and tissue-type plasminogen activator respectively), with vitronectin and with endocytosis receptors of the low-density-lipoprotein family. Understanding the significance of these interactions would be facilitated by the ability to block them individually. Using phage display, we have identified the disulfide-constrained peptide motif CFGWC with affinity for natural human PAI-1. The three-dimensional structure of a peptide containing this motif (DVPCFGWCQDA) was determined by liquid-state NMR spectroscopy. A binding site in the so-called flexible joint region of PAI-1 was suggested by molecular modelling and validated through binding studies with various competitors and site-directed mutagenesis of PAI-1. The peptide with an N-terminal biotin inhibited the binding of the uPA-PAI-1 complex to the endocytosis receptors low-density-lipoprotein-receptor-related protein 1A (LRP-1A) and very-low-density-lipoprotein receptor (VLDLR) in vitro and inhibited endocytosis of the uPA-PAI-1 complex in U937 cells. We conclude that the isolated peptide represents a novel approach to pharmacological interference with the functions of PAI-1 based on inhibition of one specific molecular interaction. 相似文献