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排序方式: 共有411条查询结果,搜索用时 15 毫秒
91.
Miika Vuorinen Ingemar Kåreholt Valtteri Julkunen Gabriela Spulber Eini Niskanen Teemu Paajanen Hilkka Soininen Miia Kivipelto Alina Solomon 《Neurobiology of aging》2013
We assessed midlife blood pressure (BP), body mass index, total cholesterol, and their changes over time in relation to cortical thickness on magnetic resonance imaging 28 years later in 63 elderly at risk of dementia. Participants in the population-based Cardiovascular Risk Factors, Aging, and Dementia study were first examined at midlife. A first follow-up was conducted after 21 years, and a second follow-up after an additional 7 years. Magnetic resonance images from the second follow-up were analyzed using algorithms developed at McGill University, Montreal, Canada. Midlife hypertension was related to thinner cortex in several brain areas, including insular, frontal, and temporal cortices. In elderly with thinner insular cortex, there was a continuous decline in systolic BP and an increase in pulse pressure after midlife, while in elderly with thicker insular cortex the decline in systolic BP started at older ages, paralleled by a decline in pulse pressure. No associations were found between body mass index, cholesterol, or apolipoprotein E ε4 allele and cortical thickness in this group of elderly at risk individuals. 相似文献
92.
93.
Filamentous fungi owe powerful abilities for decomposition of the extensive plant material, lignocellulose, and thereby are indispensable for the Earth's carbon cycle, generation of soil humic matter and formation of soil fine structure. The filamentous wood‐decaying fungi belong to the phyla Basidiomycota and Ascomycota, and are unique organisms specified to degradation of the xylem cell wall components (cellulose, hemicelluloses, lignins and extractives). The basidiomycetous wood‐decaying fungi form brackets, caps or resupinaceous (corticioid) fruiting bodies when growing on wood for dissemination of their sexual basidiospores. In particular, the ability to decompose the aromatic lignin polymers in wood is mostly restricted to the white rot basidiomycetes. The white‐rot decay of wood is possible due to secretion of organic acids, secondary metabolites, and oxidoreductive metalloenzymes, heme peroxidases and laccases, encoded by divergent gene families in these fungi. The brown rot basidiomycetes obviously depend more on a non‐enzymatic strategy for decomposition of wood cellulose and modification of lignin. This review gives a current ecological, genomic, and protein functional and phylogenetic perspective of the wood and lignocellulose‐decaying basidiomycetous fungi. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
94.
Wahlin A Anstey KJ McDonald SW Ahmed SM Kivipelto M Kunnukattil KS Mai TT Nilsson LG Streatfield PK vanBoxtel MP Kabir ZN 《Journal of cross-cultural gerontology》2008,23(1):97-105
In this paper, we present an international network of researchers from projects examining the human aging process and its
consequences. It is both vital and urgent to include aging and a life course perspective on the public health agenda, particularly
in low-income countries. By announcing the network in a publication, we wish not just to position the network but, more importantly,
to attract the attention of other potential collaborators either at the project, institutional, decision making, or applied
level. 相似文献
95.
An insertion/deletion polymorphism in the alpha2B-adrenergic receptor gene is a novel genetic risk factor for acute coronary events 总被引:5,自引:0,他引:5
Snapir A Heinonen P Tuomainen TP Alhopuro P Karvonen MK Lakka TA Nyyssönen K Salonen R Kauhanen J Valkonen VP Pesonen U Koulu M Scheinin M Salonen JT 《Journal of the American College of Cardiology》2001,37(6):1516-1522
OBJECTIVES: Our aim was to study whether an insertion/deletion (I/D) polymorphism in the alpha2B-adrenoceptor gene is associated with the risk for cardiovascular diseases. BACKGROUND: alpha2-adrenoceptors mediate contraction of vascular smooth muscle and induce coronary vasoconstriction in humans. The alpha2-adrenoceptor subtype B mediates vasoconstriction in mice. A variant of the human alpha2B-adrenoceptor gene that encodes a D of three residues in an intracellular acidic motif has been shown to confer decreased receptor desensitization. This receptor variant could, therefore, be involved in diseases associated with enhanced vasoconstriction. METHODS: This study was part of a prospective population-based study investigating risk factors for cardiovascular diseases in a cohort of middle-aged men from eastern Finland. Nine hundred twelve men aged 46 to 64 years were followed for an average time of 4.5 years. RESULTS: In this study population, 192 men (21%) had the D/D genotype; 256 (28%) had the I/I genotype, and 464 (51%) had a heterozygous genotype. In a Cox model adjusting for other coronary risk factors, men with the D/D genotype had 2.2 times (95% confidence interval: 1.1 to 4.4, p = 0.02) the risk to experience an acute coronary event (n = 15 for D/D, 10 for I/I and 12 for I/D) compared with men carrying either of the other two genotypes. The alpha2B-adrenoceptor genotype was not associated with hypertension in this study population. CONCLUSIONS: The D/D genotype of the alpha2B-adrenoceptor is a novel genetic risk factor for acute coronary events, but not for hypertension. 相似文献
96.
Huisman M Kunst AE Bopp M Borgan JK Borrell C Costa G Deboosere P Gadeyne S Glickman M Marinacci C Minder C Regidor E Valkonen T Mackenbach JP 《Lancet》2005,365(9458):493-500
97.
T J Suutari K H Valkonen T J Karttunen B M Ehn B Ekstrand U Bengtsson V Virtanen M Nieminen J Kokkonen 《Journal of investigational allergology & clinical immunology》2006,16(5):296-302
BACKGROUND: Allergic reactions to cow's milk are common in small children. One of the main protein allergens found in cow's milk is beta-lactoglobulin (beta-Lg). Reindeer and bovine milk both contain related beta-Lg proteins, but the allergenicity of reindeer beta-Lg has not previously been studied. The purpose of this study was to analyze the immunological cross-reactivity of IgE antibodies from children with cow's milk allergy to reindeer and bovine beta-Lg. METHODS: Sera from 17 children and a serum pool of 4 patients with elevated cow's milk-specific IgE were investigated. Beta-Lg from bovine and reindeer milk was isolated in native form and an enzyme-linked immunosorbent inhibition assay was developed. Bovine beta-Lg was used as a capturing antigen and the inhibiting effects of reindeer and bovine beta-Lg on the IgE binding were measured. RESULTS: Cross-reactivity patterns of bovine milk beta-Lg specific IgE to reindeer beta-Lg varied among patients. In general, reindeer beta-Lg showed significantly lower inhibition (mean 43%) of IgE binding to the capturing antigen than did bovine beta-Lg (mean 89%). In some patients, even high concentrations of reindeer beta-Lg only partly eliminated the IgE binding to bovine beta-Lg. CONCLUSIONS: The partial cross-reactivity of human anti-bovine IgE with reindeer beta-Lg suggests that it lacks important bovine epitopes and those that are recognized are only weakly bound. 相似文献
98.
Kylie S. Foo Miia L. Lehtinen Chuen Yan Leung Xiaojun Lian Jiejia Xu Wendy Keung Lin Geng Terje R.S. Kolstad Sebastian Thams Andy On-tik Wong Nicodemus Wong Kristine Bylund Chikai Zhou Xiaobing He Shao-Bo Jin Jonathan Clarke Urban Lendahl Ronald A. Li Kenneth R. Chien 《Molecular therapy》2018,26(7):1644-1659
99.
Paavonen EJ Pennonen M Roine M Valkonen S Lahikainen AR 《Journal of sleep research》2006,15(2):154-161
The aim of this study was to investigate the effects of various forms of TV exposure on the quality of children's sleep. In this randomized population-based survey questionnaires concerning TV viewing, sleep disturbances, and psychiatric symptoms were administered to 321 parents of children aged 5-6 years. Sleep disturbance scores were the main outcome measures. Active TV viewing and passive TV exposure were related to sleeping difficulties, especially sleep-wake transition disorders and overall sleep disturbances. Particularly, passive TV exposure and viewing adult-targeted TV programs were strongly related to sleep disturbances. The association remained significant when socioeconomic status, family income, family conflicts, the father's work schedule, and the child's psychiatric symptoms were controlled statistically. The adjusted odds ratios were 2.91 (95% CI 1.03-8.17) and 3.01 (95% CI 1.13-8.05), respectively. TV viewing and particularly passive TV exposure and viewing adult-targeted programs significantly increase the risk of sleeping difficulties. The results suggest that health-care professionals should be aware of the association between TV exposure and sleep disturbances. 相似文献
100.
Comparative and functional genomics of closteroviruses 总被引:2,自引:0,他引:2
The largest extant RNA genomes are found in two diverse families of positive-strand RNA viruses, the animal Coronaviridae and the plant Closteroviridae. Comparative analysis of the viruses from the latter family reveals three levels of gene conservation. The most conserved gene module defines RNA replication and is shared with plant and animal viruses in the alphavirus-like superfamily. A module of five genes that function in particle assembly and transport is a hallmark of the family Closteroviridae and was likely present in the ancestor of all three closterovirus genera. This module includes a homologue of Hsp70 molecular chaperones and three diverged copies of the capsid protein gene. The remaining genes show dramatic variation in their numbers, functions, and origins among closteroviruses within and between the genera. Proteins encoded by these genes include suppressors of RNA silencing, RNAse III, papain-like proteases, the AlkB domain implicated in RNA repair, Zn-ribbon-containing protein, and a variety of proteins with no detectable homologues in the current databases. The evolutionary processes that have shaped the complex and fluid genomes of the large RNA viruses might be similar to those that have been involved in evolution of genomic complexity in other divisions of life. 相似文献