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211.
Johannes W. S. A. Osterloh Arjan C. Videler Gina M. P. Rossi Sebastiaan P. J. van Alphen 《Tijdschrift voor gerontologie en geriatrie》2018,49(5):210-212
Behavioural counselling by nurses can enhance quality of life in elderly with a personality disorder. Although nurses have a crucial role in day-to-day treatment, there is a lack of evidence-based approaches. Based on the cognitive therapy, the treatment protocol Cognitive Model for Behavioural Interventions (CoMBI) provides an alternative nursing approach for personality disorders. 相似文献
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214.
Background
Understanding the adaptive changes that alter the function of proteins during evolution is an important question for biology and medicine. The increasing number of completely sequenced genomes from closely related organisms, as well as individuals within species, facilitates systematic detection of recent selection events by means of comparative genomics. 相似文献215.
216.
Dynamic landscape models have generally assumed random distributions of habitat although real landscapes show spatial organization
at many scales. To explore the role of spatial structure in determining the frequency of dispersal-limited forest species,
we used a cellular landscape model divided into two zones. Zones were distributed in a random, clustered, or regular spatial
pattern. Within each zone habitat cells were randomly destroyed and regenerated, and habitat density and turnover rate were
systematically varied. A hypothetical habitat-limited species dispersed between adjacent habitat cells. All trials showed
a reduced species frequency relative to a static landscape. Reduction was greater at low habitat density (P = 0.30) than at high density (0.90) suggesting the importance of habitat connectivity in controlling species frequency. The
greatest reduction occurred when habitat was concentrated in a small, regularly distributed zone at low habitat density reflecting
the enforced isolation of individual habitat cells. Very little reduction was observed when habitat cells were packed into
a small clustered zone, a situation promoting connectivity between cells. Moderate–severe frequency reduction occurred when
habitat turnover was concentrated in a clustered zone at high habitat density, but little was observed when turnover was widely
distributed in a regular or random pattern. These results can be interpreted in terms of a source-sink function in which spatial
pattern controlled the degree of contact between landscape zones and determined opportunities for dispersal between habitat
cells. We conclude that clustering of forest habitat has the potential to maintain herb species frequency in sparsely forested
landscapes. Conversely, clustering of forest disturbance in heavily forested regions, or regular distribution of forest stands
(as often occurs in agricultural regions) creates areas which are difficult to colonize, and should be avoided. 相似文献
217.
Numerous empirical studies have examined ontogenetic trajectories in plant defenses but only a few have explored the potential
mechanisms underlying those patterns. Furthermore, most documented ontogenetic trajectories in plant defenses have generally
concentrated on aboveground tissues; thus, our knowledge regarding whole plant trends in plant defenses throughout development
or potential allocation constraints between growth and defenses is limited. Here, we document changes in plant biomass, nutritional
quality and chemical defenses for below- and aboveground tissues across seven age classes of Plantago lanceolata (Plantaginaceae) to evaluate: (1) partial and whole plant ontogenetic trajectories in constitutive chemical defenses and
nutritional quality, and (2) the role of resource allocation constraints, namely root:shoot (R:S) ratios, in explaining whole
plant investment in chemical defenses over time. Overall investment in iridoid glycosides (IGs) significantly increased, while
water and nitrogen concentrations in shoot tissues decreased with plant age. Significant variation in IG content between shoot
and root tissues across development was observed: allocation of IGs into root tissues linearly increased from younger to older
plants, while non-linear shifts in allocation of IGs during ontogeny were observed for shoot tissues. Finally, R:S ratios
only weakly explained overall allocation of resources into defenses, with young stages showing a positive relationship, while
older stages showed a negative relationship between R:S ratios and IG concentrations. Ontogenetic trajectories in plant quality
and defenses within and among plant tissues can strongly influence insect herbivores’ performance and/or predation risk; thus,
they are likely to play a significant role in mediating species interactions. 相似文献
218.
Giorgio M Trinei M Migliaccio E Pelicci PG 《Nature reviews. Molecular cell biology》2007,8(9):722-728
The reactive oxygen species that are generated by mitochondrial respiration, including hydrogen peroxide (H2O2), are potent inducers of oxidative damage and mediators of ageing. It is not clear, however, whether oxidative stress is the result of a genetic programme or the by-product of physiological processes. Recent findings demonstrate that a fraction of mitochondrial H2O2, produced by a specialized enzyme as a signalling molecule in the pathway of apoptosis, induces intracellular oxidative stress and accelerates ageing. We propose that genes that control H2O2 production are selected determinants of lifespan. 相似文献
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220.
Yasuro Fuse Takahiro Okamoto Kazuhide Hayakawa Hajime Karatani Etsu Yamada 《Limnology》2016,17(3):207-221
Humic substances extracted and purified from bottom sediments of northern Lake Biwa, Japan, in November 2012 and 2013 were characterized using elemental analysis, Fourier-transform infrared spectroscopy, hydrogen-1 nuclear magnetic resonance (1H NMR) analysis, and pyrolysis gas chromatography/mass spectrometry (Py-GC/MS). The infrared (IR) bands in the spectra of humic acids showed the presence of amide linkages and polysaccharides. Results of 1H NMR analysis showed that the humic acids contained approximately twice the number of aliphatic protons as those in the Japanese soil standards used for comparison. Results of the Py-GC/MS analysis, which evaluates pyrolysis temperature dependency of the amount of pyrolysis products, showed that the generation of pyrolysis products in humic acids also differed from that in Japanese soil standards but was similar to that of phytoplankton in Lake Biwa. This analysis method is the first to provide extensive information about the chemical structure of humic substances; conventional Py-GC/MS provides limited information for a single temperature. Data suggest that humic acids in lake sediments are related to chemical characteristics of phytoplankton. Results shed new light on the origins of humic substances in deep-water-lake sediments and provide insights into material recycling in such sediments. 相似文献