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1.
A 73-year-old HTLV-1 infected male developed overt ATL following 3-years observation, and the clonality of HTLV-1 infected cells changed before overt ATL onset. 10 micrograms of DNA, extracted from mononuclear cells was digested with PstI, and the clonal proliferation of HTLV-1 infected cells was examined by Southern blotting with LTR probe. 4 bands were observed 3 years prior to ATL onset, and 2 different bands were detected 2 years and 6 months later. This suggests that in some ATL cases, the clonality of monoclonally proliferated HTLV-1 infected cells may be changeable before overt ATL onset.  相似文献   
2.
The off state current for polysilicon thin-film transistors for pixels in LCDs has been successfully reduced by introducing a polysilicon buffer layer between a polysilicon active layer fabricated by solid-phase-crystallisation (SPC) and a fused quartz substrate. Off-slate current of less than 1 pA under Vgs=-25 V at Vds=3 V was obtained for n-channel single-gate coplanar transistors using the buffer layer (400 Å)  相似文献   
3.
We study the problem of segmenting a sequence into k pieces so that the resulting segmentation satisfies monotonicity or unimodality constraints. Unimodal functions can be used to model phenomena in which a measured variable first increases to a certain level and then decreases. We combine a well-known unimodal regression algorithm with a simple dynamic-programming approach to obtain an optimal quadratic-time algorithm for the problem of unimodal k-segmentation. In addition, we describe a more efficient greedy-merging heuristic that is experimentally shown to give solutions very close to the optimal. As a concrete application of our algorithms, we describe methods for testing if a sequence behaves unimodally or not. The methods include segmentation error comparisons, permutation testing, and a BIC-based scoring scheme. Our experimental evaluation shows that our algorithms and the proposed unimodality tests give very intuitive results, for both real-valued and binary data. Niina Haiminen received the M.Sc. degree from the University of Helsinki in 2004. She is currently a Graduate Student at the Department of Computer Science of University of Helsinki, and a Researcher at the Basic Research Unit of Helsinki Institute for Information Technology. Her research interests include algorithms, bioinformatics, and data mining. Aristides Gionis received the Ph.D. degree from Stanford University in 2003, and he is currently a Senior Researcher at the Basic Research Unit of Helsinki Institute for Information Technology. His research experience includes summer internship positions at Bell Labs, AT&T Labs, and Microsoft Research. His research areas are data mining, algorithms, and databases. Kari Laasonen received the M.Sc. degree in Theoretical Physics in 1995 from the University of Helsinki. He is currently a Graduate Student in Computer Science at the University of Helsinki and a Researcher at the Basic Research Unit of Helsinki Institute for Information Technology. His research is focused on algorithms and data analysis methods for pervasive computing.  相似文献   
4.
Currant oils have special health properties due to their moderate contents of α‐linolenic, γ‐linolenic and stearidonic acids. The distribution of fatty acids (FA) in the triacylglycerols (TAG) may affect the beneficial effects. Seed oils of wild northern red currant (NRC) (Ribes spicatum L.) from Northern Finland and of wild alpine currant (AC) (R. alpinum L.) from the South‐West coast of Finland were investigated. The purified TAG were analysed by tandem mass spectrometry by applying the ammonia negative ion chemical ionisation – collision‐induced dissociation method. Molecular weight fractions rich in C18:3 FA and C18:4 FA were investigated. Of the total oil, the molecular weight species 54:7 (ACN:DB), 54:8 and 54:9 were more abundant in NRC than in AC, being 21.0%, 15.8%, 7.4% and 16.2%, 11.2%, 4.8%, respectively (p <0.05). The species 52:6 was more abundant in AC (3.1%) than in NRC (2.6%) (p <0.05). The preferential order of FA to be in the sn‐2 position in both berries was typically C18:1 > C18:2 > C18:4 > C18:3. No difference was observed between relative locations of C16:0 FA and C18:3 FA in either of the oils. Within the TAG consisting of FA combinations C18:3/C18:3/C18:1 (54:7), C18:1 was more preferentially in the sn‐2 position (p <0.05) in AC (93.2%) than in NRC (74.6%), and in the case of C18:3, the preference was vice versa. Within the molecular weight species 54:9, FA combination C18:4/C18:3/C18:2, linoleic acid preferentially occupied the secondary position (p <0.005) in both berries, and the proportion of the TAG regioisomer pair sn‐C18:3‐C18:4‐C18:2 + sn‐C18:2‐C18:4‐C18:3 was more abundant (30.2%) in NRC than in AC (15.3%). Within the TAG species 52:6, proportions of all the existing combinations, C16:0/C18:3/C18:3, C16:0/C18:4/C18:2 and C16:1/C18:3/C18:2, varied between the two berry species (p <0.005).  相似文献   
5.
A gene (POF1) has been cloned, which confers upon yeast (Saccharomyces cerevisiae) the ability to decarboxylate phenolic acids such as ferulic and trans-cinnamic acid. This property was previously shown to be a cause of phenolic off-flavour production in wort fermentations. The identity of the cloned gene was confirmed as POF1 by gene disruption techniques. Southern blotting of total genomic DNA revealed that sequences homologous to POF1 are conserved in Pof? brewing strains of Sacch. cerevisiae. The transformation of a Pof? lager strain with the cloned POF1 gene led to the production of an aroma characteristic of a phenolic off-flavour, when the transformed strain was used in wort fermentations. This latter observation suggests that the Pof? phenotype of brewers' yeast is specifically due to the absence of a functional POF1 gene.  相似文献   
6.
This study examined the effects of chemosensory performance of two age groups on ratings of the just-right intensity of odor, flavor and coolness. Two experiments were conducted: (1) creation of a sensory profile by a trained panel and (2) hedonic testing of the yogurt samples by young (n=47, 20–35 years) and elderly (n=45, 65–82 years) subjects, who also participated in tests measuring their chemosensory performance. Eight yogurt samples (2×2×2 factorial design) were flavored with 6 or 10% sucrose, 0.2 or 0.8% lemon aroma and 0.004 or 0.012% menthol. Young subjects outperformed elderly in the olfactory, gustatory and trigeminal perception tests. Their performance in the chemosensory tests affected hedonic ratings of yogurts, especially in the case of the elderly. Among the elderly, just-right flavor was affected by the performance in olfactory, gustatory (sweet, sour) and trigeminal (menthol) tests. Just-right coolness was affected by olfactory perception and by identification of sweet taste. Pleasantness was affected by olfactory and menthol perception. Thus, stimulus-specific losses in chemosensory acuity of the elderly may lead to distorted perception of foods.  相似文献   
7.
The paper considers the use of mixed methods in international business research by reviewing empirical studies in four major journals. A total of 484 articles were reviewed, 68 of which had applied a mixed method strategy. In our analysis we categorize mixed methods according to their use in different stages of the research process and provide a range of alternative designs for mixing qualitative and quantitative methods.  相似文献   
8.
BACKGROUND: Red clover (Trifolium pratense L.), a widely used fodder, has recently received considerable interest as a valuable source of isoflavones for many health‐related applications. The aim of this study was to analyse the concentrations of four isoflavones, daidzein, genistein, formononetin and biochanin A, in extracts of leaves, stems, roots and different coloured flowers from red clover by high‐performance liquid chromatography and to determine the antifungal activities of the extracts. RESULTS: Among greenhouse‐grown samples the highest amounts of daidzein and genistein were found in petioles (0.11–0.28 and 0.30–0.54 mg g?1 respectively), while leaves were rich in formononetin and biochanin A (5.57–9.05 and 10.94–14.59 mg g?1 respectively). High formononetin concentrations were found in roots, but very little biochanin A. Among field‐grown samples the highest concentrations of daidzein and genistein were detected in stems collected in August (0.24 and 0.55 mg g?1 respectively), while the highest amounts of formononetin and biochanin A were found in young leaves collected in June (7.47 and 9.69 mg g?1 respectively). Most of the extracts inhibited the growth of Drechslera teres, while the root extract showed the strongest effect against Microdochium nivale. CONCLUSION: High levels of bioactive compounds found not only in inflorescences but also in roots, leaves and stems suggest that red clover may be an inexpensive and valuable resource for many applications. Copyright © 2007 Society of Chemical Industry  相似文献   
9.
Chronic inflammation has been associated with several chronic diseases, such as age-related macular degeneration (AMD). The NLRP3 inflammasome is a central proinflammatory signaling complex that triggers caspase-1 activation leading to the maturation of IL-1β. We have previously shown that the inhibition of the chaperone protein, Hsp90, prevents NLRP3 activation in human retinal pigment epithelial (RPE) cells; these are cells which play a central role in the pathogenesis of AMD. In that study, we used a well-known Hsp90 inhibitor geldanamycin, but it cannot be used as a therapy due to its adverse effects, including ocular toxicity. Here, we have tested the effects of a novel Hsp90 inhibitor, TAS-116, on NLRP3 activation using geldanamycin as a reference compound. Using our existing protocol, inflammasome activation was induced in IL-1α-primed ARPE-19 cells with the proteasome and autophagy inhibitors MG-132 and bafilomycin A1, respectively. Intracellular caspase-1 activity was determined using a commercial caspase-1 activity kit and the FLICA assay. The levels of IL-1β were measured from cell culture medium samples by ELISA. Cell viability was monitored by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test and lactate dehydrogenase (LDH) measurements. Our findings show that TAS-116 could prevent the activation of caspase-1, subsequently reducing the release of mature IL-1β. TAS-116 has a better in vitro therapeutic index than geldanamycin. In summary, TAS-116 appears to be a well-tolerated Hsp90 inhibitor, with the capability to prevent the activation of the NLRP3 inflammasome in human RPE cells.  相似文献   
10.
ABSTRACT

The efficacies of UV photolysis, UV-activated persulfate (UV/PS), and combined UV/Fe2+-activated persulfate (UV/PS/Fe2+) systems for degrading of different organic micropollutants in ultrapure water and groundwater were examined and compared. The studied micropollutants belonging to the different classes involved an artificial sweetener acesulfame K (ACE), beta-lactam antibiotic amoxicillin (AMX), and endocrine disrupting compound 4-nonylphenol (NP). Among the studied systems, the UV/PS/Fe2+ process showed the highest performance both in degradation and in mineralization of ACE (UVA-induced systems; kapp = 0.126 1/min and 80.3% TOC removal) and AMX (UVC-induced systems; kapp = 1.383 1/min and 85.4% TOC removal), followed by the UV/PS process. In the case of NP trials, the application of UVC/PS systems was the most promising, and after careful adjustment of oxidant concentration, it demonstrated a considerable improvement in the target compound degradation (at a NP/PS molar ratio of 1/4 kapp = 0.024 1/min) compared with the UVC photolysis (kapp = 0.016 1/min). Irrespective of the applied UV-induced treatment process, the efficacy of target compounds degradation was lower in groundwater as compared with ultrapure water trials.  相似文献   
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