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Objectives: The purpose of this study was to identify factors influencing the motivation for regular dental check‐ups and anxiety about future dental problems in the elderly. Background: Regular dental check‐ups are important to maintain oral health. Anxiety affects the quality of life of the elderly. However, few studies have investigated the factors influencing the motivation for regular dental check‐ups and anxiety in the elderly. Materials and methods: Among 452 elderly persons, 215 participants provided useful answers to our questionnaire. The questionnaire consisted of items concerning oral and living conditions of the subjects. Logistic regression analysis was conducted. Results: The mean age of the study sample was 75.7 ± 5.8 years. The percentage of edentulous subjects was 12.1%. The motivation for regular dental check‐ups was significantly positively correlated with the number of teeth present (p < 0.01), using inter‐dental brushes (p < 0.01), being on regular prescribed medication (p < 0.05), and having experience of providing oral care for the bedridden (p < 0.05). Anxiety about future oral problems was significantly associated with self‐rated health status (p < 0.01) and the presence of dentists who could be counted on to provide domiciliary visits (p < 0.05). Conclusion: The participants of this study had a high motivation for regular dental check‐ups, but were concerned about the future, particularly if they became bedridden. 相似文献
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DANILO DRAGONI HANS PETER SCHMID CRAIG A. WAYSON HENRY POTTER C. SUSAN B. GRIMMOND JAMES C. RANDOLPH 《Global Change Biology》2011,17(2):886-897
Observations of net ecosystem exchange (NEE) of carbon and its biophysical drivers have been collected at the AmeriFlux site in the Morgan‐Monroe State Forest (MMSF) in Indiana, USA since 1998. Thus, this is one of the few deciduous forest sites in the world, where a decadal analysis on net ecosystem productivity (NEP) trends is possible. Despite the large interannual variability in NEP, the observations show a significant increase in forest productivity over the past 10 years (by an annual increment of about 10 g C m?2 yr?1). There is evidence that this trend can be explained by longer vegetative seasons, caused by extension of the vegetative activity in the fall. Both phenological and flux observations indicate that the vegetative season extended later in the fall with an increase in length of about 3 days yr?1 for the past 10 years. However, these changes are responsible for only 50% of the total annual gain in forest productivity in the past decade. A negative trend in air and soil temperature during the winter months may explain an equivalent increase in NEP through a decrease in ecosystem respiration. 相似文献
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Jianjun Wang Janne Soininen Yong Zhang Beixin Wang Xiangdong Yang Ji Shen 《Global Ecology and Biogeography》2012,21(7):743-750
Aim While ecologists have long been interested in diversity in mountain regions, elevational patterns in beta diversity are still rarely studied across different life forms ranging from micro‐ to macroorganisms. Also, it is not known whether the patterns in turnover among organism groups are affected by the degree to which the environment is modified by human activities. Location Laojun Mountain, Yunnan Province, China. Methods The beta diversity patterns of benthic microorganisms (i.e. diatoms and bacteria) and macroorganisms (i.e. macroinvertebrates) in a stony stream were simultaneously investigated between elevations of 1820 and 4050 m. Data were analysed by using a distance‐based approach and variation partitioning based on canonical redundancy analysis. Results Analyses of community dissimilarities between adjacent sampling sites showed comparable small‐scale beta diversity along the elevational gradient for the organism groups. However, bacteria clearly showed the lowest elevational turnover when analyses were conducted simultaneously for all pairwise sites. Variation partitioning indicated that species turnover was mostly related to environmental heterogeneity and spatial gradients including horizontal distance and elevation, while purely human impacts were shown to be less important. Main conclusions The elevational beta diversity at large scales was lower for bacteria than for eukaryotic microorganisms or macroorganisms, perhaps indicative of high dispersal ability and good adaptability of bacteria to harsh environmental conditions. However, the small‐scale beta diversity did not differ among the groups. Elevation was the major driver for the turnover of eukaryotic organisms, while the turnover of bacteria was correlated more with environmental variation. 相似文献
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A rare non‐trilobite artiopodan from the Guzhangian (Cambrian Series 3) Weeks Formation Konservat‐Lagerstätte in Utah,USA 下载免费PDF全文
Javier Ortega‐Hernández Rudy Lerosey‐Aubril Carlo Kier Enrico Bonino 《Palaeontology》2015,58(2):265-276
We describe a weakly biomineralized non‐trilobite artiopodan arthropod from the Guzhangian Weeks Formation of Utah. Falcatamacaris bellua gen. et sp. nov. is typified by a thin calcitic cuticle, broad cephalon without eyes or dorsal ecdysial sutures, an elongate trunk with distinctively sickle‐shaped pleural spines and a long tailspine with a bifurcate termination. The precise affinities of Falcatamacaris gen. nov. are problematic due to the presence of unique features within Artiopoda, such as the peculiar morphology of the pleural and posterior regions of the trunk. Possible affinities with aglaspidid‐like arthropods and concilitergans are discussed based on the possession of 11 trunk tergites, edge‐to‐edge articulations and overall body spinosity. The new taxon highlights the importance of the Weeks Formation Konservat‐Lagerstätte for further understanding the diversity of extinct arthropod groups in the upper Cambrian. 相似文献
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Abstract The forage diggings of medium‐sized ground‐dwelling mammals (bandicoots and potoroos) were recorded over two seasons across 136 forested study sites, representing a stratified sample of the climatic, geological and topographic features of far south‐eastern mainland Australia. Diggings, presumably left by bandicoots, were recorded at a total of 42 sites, and those of potoroos at 27 sites. Statistical models were developed for the occurrence of these diggings, based on environmental attributes measured for each site. At a landscape scale, mean minimum temperature of the coldest month was an important explanatory variable for both groups of animals, with likelihood of their occurrence increasing with increasing temperature during that period. More locally, soil fertility and time since last fire also influenced the occurrence of bandicoot and potoroo diggings, while density of ground cover was additionally important in explaining the occurrence of bandicoot diggings. Bandicoot and potoroo diggings were more likely to occur with decreasing soil fertility and increasing time since fire, while occurrence of bandicoot diggings also increased with increasing density of ground cover. The possible management implications of our findings for conservation of medium‐sized ground‐dwelling mammals in multiple‐use forests are discussed. 相似文献
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Carlos Ríos Wolf E. Arntz Dieter Gerdes Erika Mutschke Américo Montiel 《Polar Biology》2007,31(1):89-100
Macrocystis pyrifera (L.) C. Agardh is a characteristic macroalga in the Magellan region covering almost 30% of the shallow coastal waters. The
focus of this study was to analyse the spatial and seasonal patterns in macrofauna communities associated to the holdfasts
of Macrocystis pyrifera at two study sites in the Straits of Magellan, South Chile. In total, 114 species from 10 major taxa were isolated from the
holdfasts. MDS clearly separated the holdfast fauna collected in different seasons, with autumn and winter collections being
richer in terms of species richness and abundance as compared to the spring and summer situation. MDS also clearly separated
the holdfast associated faunas of the two study sites, Bahía Laredo and Fuerte Bulnes. The community structure and species
composition of the associated macro-invertebrates and vertebrates appeared rather heterogeneous, probably due to the extremely
heterogeneous environmental conditions along the entire coastline of the Subantarctic Magellan region. 相似文献
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《Palaeoworld》2014,23(3-4):240-251
The origin and pigmentation of red beds have long been investigated, but mainly on continental settings and carbonate facies (including deep marine red beds). This paper focuses on the shallow marine clastic red beds developed in South China during the Silurian. Based on the sedimentological and geochemical analyses on red layers, green layers and laminae of the Rongxi Formation (Llandovery, Lower Silurian) of Xiushan, southeastern Chongqing, known as the ‘lower red beds’ (LRBs), the following observations are made: (1) the LRBs are primary red beds whereas the green layers are secondary (i.e., formed during early diagenesis); (2) the color differentiation of sediments shows little relevance to the bottom redox potential shift but has a close relationship to grain size and sediment sorting which may be caused by sea level changes and tides. The controlling factors of LRBs pigmentation are significantly different from those of deep marine red beds, and some coeval red beds in North America and Europe. It is noted that, among the shallow marine clastic red beds, the sedimentological and geochemical signatures from the laminae seem to better indicate the environmental conditions than those derived from the layers. 相似文献
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M.J. Torres A. Hidalgo‐García E.J. Bedmar M.J. Delgado 《Journal of applied microbiology》2013,114(6):1772-1781
Aim
In this work, phenotypic analyses of a Ensifer meliloti fixN1 mutant under free‐living and symbiotic conditions have been carried out.Methods and Results
Ensifer meliloti fixN1 mutant showed a defect in growth as well as in TMPD‐dependent oxidase activity when cells were incubated under micro‐oxic conditions. Furthermore, haem c staining analyses of a fixN1 and a fixP1 mutant identified two membrane‐bound c‐type cytochromes of 27 and 32 kDa, present in microaerobically grown cells and in bacteroids, as the FixO and FixP components of the E. meliloti cbb3 oxidase. Under symbiotic conditions, fixN1 mutant showed a clear nitrogen fixation defect in alfalfa plants that were grown in an N‐free nutrient solution during 3 weeks. However, in plants grown for a longer period, fixNOQP1 copy was not indispensable for symbiotic nitrogen fixation.Conclusions
The copy 1 of the fixNOQP operon is involved in E. meliloti respiration and growth under micro‐oxic conditions as well as in the expression of the FixO and FixP components of the cbb3 oxidase present in free‐living microaerobic cultures and in bacteroids. This copy is important for nitrogen fixation during the early steps of the symbiosis.Significance and Impact of the Study
It is the first time that a functional analysis of the E. meliloti copy 1 of the fixNOQP operon is performed. In this work, the cytochromes c that constitute the cbb3 oxidase operating in free‐living micro‐oxic cultures and in bacteroids of E. meliloti have been identified. 相似文献16.
Li Xiao Kentaro Kaneyasu Yasukazu Saitoh Yoichi Terashima Yasunori Kowata Nobuhiko Miwa 《Journal of cellular biochemistry》2009,106(4):589-598
Irradiation with ultraviolet‐A (UVA) ray at doses of 20–100 J/cm2 diminished the cell viability of human keratinocytes HaCaT and human melanoma cells HMV‐II, both of which were protected by pre‐irradiational administration with the ascorbic acid (Asc) derivative, VC‐IP (2,3,5,6‐O‐tetra‐2′‐hexyldecanoyl‐L‐ascorbic acid; vitamin C‐isopalmityl tetraester), which is the first lipoidic‐liquiform pro‐vitamin C by itself that is materialized by esterization of all four intramolecular hydroxyl groups of an Asc molecule with branched chain fatty groups, resulting in molecular fluidity higher than that of the corresponding straight chains. Irradiation with UVA to HaCaT keratinocytes was shown to cause the formation of 8‐hydroxydeoxyguanosine (8‐OHdG), translocation of phosphatidylserine in the inner layer into the outer layer of cell membrane, and lowering of a mitochondrial membrane potential, all of which were repressed by pre‐irradiational administration with VC‐IP. Expression of p53 gene, another hallmark of UV‐induced DNA damages, was promoted by UVA irradiation to the keratinocytes but also repressed by VC‐IP. Administration with VC‐IP of 10–50 µM to human fibroblasts NHDF achieved the enhancement of collagen synthesis, repression of matrix metalloprotease‐2/9 activity, and increasing of intracellular Asc contents more markedly than that with Asc itself of the same concentrations. Thus UVA‐induced diverse harmful effects could be prevented by VC‐IP, which was suggested to ensue intrinsically from the persistent enrichment of intracellular Asc, through esterolytic conversion of VC‐IP to a free‐form Asc molecule, resulting in relief to UVA‐caused oxidative stress. J. Cell. Biochem. 106: 589–598, 2009. © 2009 Wiley‐Liss, Inc. 相似文献
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The enzymatic synthesis of N‐acetyl‐lactosamine (LacNAc) by the transgalactosylation of N‐acetyl‐D ‐glucosamine (GlcNAc), catalyzed by the β‐galactosidase from Bacillus circulans (BcβGal), was studied in hydro‐organic media, starting from o‐nitrophenyl‐β‐D ‐galactopyranoside (oNPG) as a galactosyl donor. Thermal stability and synthesis activity of BcβGal were shown to depend on the organic solvent polarity, characterized by its Log P value. BcβGal was thus most stable in 10% (v/v) t‐BuOH, an organic solvent found to have a stabilizing and/or weakly denaturing property, which was confirmed for high t‐BuOH concentrations. In the same manner, the optimal synthesis yield increased as the Log P value of the organic solvent increased. The best results were obtained for reactions carried out in 10% (v/v) pyridine or 2‐methyl‐2‐butanol, which gave 47% GlcNAc transgalactosylation yield based on starting oNPG, of which 23% (11 mM; 4.3 g/L) consisted in LacNAc synthesis. Furthermore, it was also established that both the GlcNAc transgalactosylation yield and the enzyme regioselectivity depended on the percentage of organic solvent used, the optimal percentage varying from 10 to 40% (v/v), depending on the solvent. This phenomenon was found to correlate mainly with the thermodynamic activity of water (aw) in the aqueous organic solvent mixture, which was found to be optimal when close to 0.96, whatever the organic solvent used. Finally, this study highlighted the fact that the regioselectivity of BcβGal for 1‐4 linkage formation could be advantageously managed by controlling the aw parameter. © 2010 American Institute of Chemical Engineers Biotechnol. Prog., 2010 相似文献
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Odontophoral cartilages are located in the molluscan buccal mass and support the movement of the radula during feeding. The structural diversity of odontophoral cartilages is currently known only from limited taxa, but this information is important for interpreting phylogeny and for understanding the biomechanical operation of the buccal mass. Caenogastropods exhibit a wide variety of feeding strategies, but there is little comparative information on cartilage morphology within this group. The morphology of caenogastropod odontophoral cartilages is currently known only from dissection and histology, although preliminary results suggest that they may be structurally diverse. A comparative morphological survey of 18 caenogastropods and three noncaenogastropods has been conducted, sampling most major caenogastropod superfamilies. Three‐dimensional models of the odontophoral cartilages were generated using X‐ray microscopy (micro‐CT) and reconstruction by image segmentation. Considerable morphological diversity of the odontophoral cartilages was found within Caenogastropoda, including the presence of thin cartilaginous appendages, asymmetrically overlapping cartilages, and reflexed cartilage margins. Many basal caenogastropod taxa possess previously unidentified cartilaginous support structures below the radula (subradular cartilages), which may be homologous to the dorsal cartilages of other gastropods. As subradular cartilages were absent in carnivorous caenogastropods, adaptation to trophic specialization is likely. However, incongruence with specific feeding strategies or body size suggests that the morphology of odontophoral cartilages is constrained by phylogeny, representing a new source of morphological characters to improve the phylogenetic resolution of this group. J. Morphol. 2009. © 2008 Wiley‐Liss, Inc. 相似文献