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The aim of this experiment was to investigate pigs’ preferences for rooting materials. Eighteen materials were allocated to six categories each of which consisted of three similar materials based on characteristics such as structure, size of particles, complexity, destructibility and digestibility. Twelve pairs of pigs chose among the three materials of each of the six categories in a balanced design. Within each category each pair was given four instantaneous choices among the three materials in a three-armed maze. ‘No choice’ was scored if the pigs did not enter one of the maze-arms within 90 s. Thus there were four options in each choice situation. The results were analysed using a random utility model incorporating random intercepts to account for the repeated testing of the same animals. The pigs expressed clear preferences within the category EARTH, where compost and peat were preferred to wood-shavings and no choice. In the category CHIP the most probable rank-order was spruce chip, willow chip, fir chip and no choice, while in the category ROUGH the most probable rank-order was maize-silage, grass silage, sugar beets and no choice. However, in these two categories none of the probabilities were sufficiently large to signify a preference for any of the three materials although the probabilities of the ‘no choice’ option were low. The pigs expressed no preferences among any of the four options including ‘no choice’ in the categories TOY (sisal robe, Bite-Rite, wooden beam), HAY (alfalfa hay mixed with straw, seed grass hay, barley straw with under-seed), and STRAW (long straw, chopped straw and straw pellets).  相似文献   
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Objective To determine the impact of the European Union’s Clinical Trials Directive on the number of academic drug trials carried out in Denmark.Design Retrospective review of applications for drug trials to the Danish Medicines Agency, 1993-2006.Review methods Applications for drug trials for alternate years were classified as academic or commercial trials. A random subset of academic trials was reviewed for number of participants in and intended monitoring of the trials.Results Academic and commercial drug trials showed an identical steady decline from 1993 to 2006 and no noticeable change after 2004 when good clinical practice became mandatory for academic trials.Conclusion The Clinical Trials Directive introduced in May 2004 to ensure good clinical practice for academic drug trials was not associated with a decline in research activity in Denmark; presumably because good clinical practice units had already been in place in Danish universities since 1999. With such an infrastructure academic researchers can do drug trials under the same regulations as drug companies.  相似文献   
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BackgroundAppendiceal goblet cell carcinoids (GCCs) exhibit neuroendocrine and adenocarcinoma features.ResultsMedian age for f/m was 59/58 years, respectively, and similar for localized and disseminated disease. At diagnosis 54 patients had localized appendiceal disease (f/m: 29/25). According to TNM 24% had Stage I, 70% had Stage II and 6% had Stage III. Twenty-nine patients had disseminated disease (f/m: 27/2). Chromogranin A, synaptophysin and p53 were positive in >90%. Serotonin was positive in 70%. Median Ki67 index was 32% (6-75%) and higher in Tang group C (50%) compared to group A (30%; p<0.0001), and group B (30%; p<0.004). All patients had surgery. Sixty-three (76%) had radical resections including all patients with localized disease. Median OS was 83 months. The 1-, 5- and 10-year survival rates were 90%, 58%, and 38%, respectively. For localized disease OS was 164 months and 1-, 5- and 10-year survival rates were 100%, 80%, and 55%, respectively. For disseminated disease OS was 19 months and 1-, 5- and 10-year survival rates were 73%, 18% and 6%, respectively. The 1-, 5- and 10 year-survival rates for f/m were 87%/96%, 49%/76% and 31%/57%, respectively (p = 0.02). According to the Tang classification group A, B, and C OS was 118, 83 and 20 months, respectively (p = 0.0002).ConclusionThe Tang classification was found to be a significant prognostic factor, while the Ki67 index was not. Localized GCCs occurred equally in males and females, while disseminated GCCs were mostly seen in females. Median age of patients with localized disease and disseminated disease was identical. Cox regression analysis found Stage IV, focally positive synaptophysin and non-radical surgery as strongest negative prognostic factors.  相似文献   
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In human longevity studies, single nucleotide polymorphism (SNP) analysis identified a large number of genetic variants with small effects, yet not easily replicable in different populations. New insights may come from the combined analysis of different SNPs, especially when grouped by metabolic pathway. We applied this approach to study the joint effect on longevity of SNPs belonging to three candidate pathways, the insulin/insulin‐like growth factor signalling (IIS), DNA repair and pro/antioxidant. We analysed data from 1,058 tagging SNPs in 140 genes, collected in 1825 subjects (1,089 unrelated nonagenarians from the Danish 1905 Birth Cohort Study and 736 Danish controls aged 46–55 years) for evaluating synergic interactions by SNPsyn. Synergies were further tested by the multidimensional reduction (MDR) approach, both intra‐ and interpathways. The best combinations (FDR<0.0001) resulted those encompassing IGF1R‐rs12437963 and PTPN1‐rs6067484, TP53‐rs2078486 and ERCC2‐rs50871, TXNRD1‐rs17202060 and TP53‐rs2078486, the latter two supporting a central role of TP53 in mediating the concerted activation of the DNA repair and pro‐antioxidant pathways in human longevity. Results were consistently replicated with both approaches, as well as a significant effect on longevity was found for the GHSR gene, which also interacts with partners belonging to both IIS and DNA repair pathways (PAPPA, PTPN1, PARK7, MRE11A). The combination GHSR‐MREA11, positively associated with longevity by MDR, was further found influencing longitudinal survival in nonagenarian females (= .026). Results here presented highlight the validity of SNP‐SNP interactions analyses for investigating the genetics of human longevity, confirming previously identified markers but also pointing to novel genes as central nodes of additional networks involved in human longevity.  相似文献   
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In this study, 23 Debaryomyces hansenii strains, isolated from cheese and fish gut, were investigated in vitro for potential probiotic properties i.e. (1) survival under in vitro GI (gastrointestinal) conditions with different oxygen levels, (2) adhesion to Caco-2 intestinal epithelial cells and mucin, and (3) modulation of pro- and anti-inflammatory cytokine secretion by human monocyte-derived dendritic cells. As references two commercially available probiotic Saccharomyces cerevisiae var. boulardii (S. boulardii) strains were included in the study. Our results demonstrate that the different D. hansenii yeast strains had very diverse properties which could potentially lead to different probiotic effects. One strain of D. hansenii (DI 09) was capable of surviving GI stress conditions, although not to the same degree as the S. boulardii strains. This DI 09 strain, however, adhered more strongly to Caco-2 cells and mucin than the S. boulardii strains. Additionally, two D. hansenii strains (DI 10 and DI 15) elicited a higher IL-10/IL-12 ratio than the S. boulardii strains, indicating a higher anti-inflammatory effects on human dendritic cells. Finally, one strain of D. hansenii (DI 02) was evaluated as the best probiotic candidate because of its outstanding ability to survive the GI stresses, to adhere to Caco-2 cells and mucin and to induce a high IL-10/IL-12 ratio. In conclusion, this study shows that strains of D. hansenii may offer promising probiotic traits relevant for further study.  相似文献   
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Background  

Leaf-cutting ants live in symbiosis with a fungus that they rear for food by providing it with live plant material. Until recently the fungus' main inferred function was to make otherwise inaccessible cell wall degradation products available to the ants, but new studies have shed doubt on this idea. To provide evidence for the cell wall degrading capacity of the attine ant symbiont, we designed PCR primers from conserved regions of known xylanase genes, to be used in PCR with genomic DNA from the symbiont as template. We also measured xylanase, cellulase and proteinase activities in the fungus gardens in order to investigate the dynamics of degradation activities.  相似文献   
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