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61.
Two-dimensional gel electrophoresis analysis of and total cell protein determination for three bacterial isolates from marine waters at the onset and after 24 h of energy and nutrient deprivation demonstrated that the three isolates exhibited different pathways of starvation survival. Two strains appeared to synthesize new proteins during starvation.  相似文献   
62.
ABSTRACT: BACKGROUND: The presence of diabetes mellitus poses a challenge in the treatment of patients with acute myocardial infarction (AMI). We aimed to evaluate the sex-specific outcomes of diabetic and non-diabetic patients with AMI who have undergone percutaneous coronary intervention (PCI). METHODS: Data of the Estonian Myocardial Infarction Registry for years 2006[EN DASH]2009 were linked with the Health Insurance Fund database and the Population Registry. Hazard ratios (HRs) with the 95 % confidence intervals (CIs) for the primary composite outcome (non-fatal AMI, revascularization, or death whichever occurred first) and for the secondary outcome (all cause mortality) were calculated comparing diabetic with non-diabetic patients by sex. RESULTS: In the final study population (n = 1652), 14.6 % of the men and 24.0 % of the women had diabetes. Overall, the diabetics had higher rates of cardiovascular risk factors, co-morbidities, and 3[EN DASH]4 vessel disease among both men and women (p < 0.01). Among women, the diabetic patients were younger, they presented later and less often with typical symptoms of chest pain than the non-diabetics (p < 0.01). Women with diabetes received aspirin and reperfusion for ST-segment elevation AMI less often than those without diabetes (p < 0.01). During a follow-up of over two years, in multivariate analysis, diabetes was associated with worse outcomes only in women: the adjusted HR for the primary outcome 1.44 (95 % CI 1.05 [MINUS SIGN] 1.96) and for the secondary outcome 1.83 (95 % CI 1.17 [MINUS SIGN] 2.89). These results were largely driven by a high (12.0 %) mortality during hospitalization of diabetic women. CONCLUSIONS: Diabetic women with AMI who have undergone PCI are a high-risk group warranting special attention in treatment strategies, especially during hospitalization. There is a need to improve the expertise to detect AMI earlier, decrease disparities in management, and find targeted PCI strategies with adjunctive antithrombotic regimes in women with diabetes.  相似文献   
63.
The aim of the current study was to test the suitability of microwave heating for stopping carbohydrate transformations in plant material. Needles and branches of Pinus sylvestris were treated in microwave oven (2.45 GHz, 800W) and compared to the samples treated in boiling ethanol (96 %). In extracts obtained from the microwaved material the ratio of sucrose to hexoses (glucose and fructose) decreased, while ethanol treatment resulted in stable extracts. The carbohydrate composition in dry samples estimated after a month of storage was persistent. The boiling of needles in ethanol in microwave oven gave the same results as boiling on a heating plate. In the woody material, differently from the needles, the total concentration of measured carbohydrates depended significantly on the preparation method. In the case of needles, the treatment of plant material in ethanol was better suited for the determination of carbohydrate levels than the microwave treatment.  相似文献   
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Changes in the forest management practices have strongly influenced the distribution of species inhabiting old-growth forests. The epiphytic woodland lichen Lobaria pulmonaria is frequently used as a model species to study the factors affecting the population biology of lichens. We sampled 252 L. pulmonaria individuals from 12 populations representing three woodland types differing in their ecological continuity and management intensity in Estonia. We used eight mycobiont-specific microsatellite loci to quantify genetic diversity among the populations. We calculated the Sørensen distance to estimate genetic dissimilarity among individuals within populations. We revealed that L. pulmonaria populations have significantly higher genetic diversity in old-growth forests than in managed forests and wooded meadows. We detected a significant woodland-type-specific pattern of genetic dissimilarity among neighbouring L. pulmonaria individuals, which suggests that in wooded meadows and managed forests dominating is vegetative reproduction. The vegetative dispersal distance between the host trees of L. pulmonaria was found to be only 15–30 m. Genetic dissimilarity among individuals was also dependent on tree species and trunk diameter. Lobaria pulmonaria populations in managed forests included less juveniles compared to old-growth forests and wooded meadows, indicating that forest management influences life stage structure within populations. We conclude that as intensive stand management reduces the genetic diversity of threatened species in woodland habitats, particular attention should be paid to the preservation of remnant populations in old-growth habitats. Within managed habitats, conservation management should target on maintenance of the stand’s structural diversity and availability of potential host trees.  相似文献   
66.
One of the main challenges in biodiversity conservation is to curb a further degradation and loss of high-quality habitats. In agricultural matrix landscapes, the detection of alternative habitats for habitat specialists may be a solution. Historic old parks or landscape gardens around manor houses and castles are cultural heritage of nobles, but their value in harbouring biodiversity is poorly acknowledged. Therefore we evaluated the potential of old rural parks to serve as a habitat for nemoral forest species. We recorded stand structure and the presence of forest biodiversity indicators in 74 closed-canopy stands of historic parks and compared them with 93 neighbouring mature forest remnants on ancient forest land. We estimated the importance of stand structure in relation to habitat type on biodiversity indicators. Finally we suggest single-value indicator-complexes for the cost-efficient assessment of the conservation value of forests and forest-like habitats. Park stands outclassed reference forests in several individual structural characteristics, and in combined indicators of habitat quality and biodiversity. Forests had higher estimates for the combined indicator of dead wood, but large-diameter dead wood types were more abundant in parks. Woodpeckers, several old-growth indicator epiphytes and forest herbs had successfully become established in planted forest-like park fragments. Old rural parks resemble high-conservation-value forests more than the best preserved contemporary forest remnants. After the century needed to overcome immigration delay, old parks do provide a refugium for temperate deciduous forest species. Consequently, biodiversity-targeted management should retain and enhance old-growth attributes in forests and on the peripheries of parks: e.g. preserving old trees to provide service for epiphytes, hollow trees and an understorey mosaic for birds and bats; dead wood elements for saproxylic insects and fungi; limited mowing frequency and increased cutting height for forest herbs. Forestry should enhance the recovery of mixed deciduous stands and avoid conifer plantations.  相似文献   
67.
A stereochemically safe high‐yielding procedure for linking unprotected as well as protected hydroxycarboxylic acids to chiral secondary alcohols via glycolic acid linker is proposed. L‐menthol has been linked with both enantiomers of mandelic, malic, and methoxyphenylacetic acid using bromo‐ or iodoacetyl group as a precursor of the glycolic acid linker. High‐field nuclear magnetic resonance (NMR) and chiral high‐performance liquid chromatography (HPLC) determination of high diastereomeric ratio (dr) (>99%) of the products bearing remote stereocenters was explored. Chiral HPLC allowed quantitation of the diastereomers up to dr 99.9/0.1. High‐field NMR quantitation of the diastereomeric and parent alcoholic impurities in esters was demonstrated at the molar 0.3% and 0.03% levels, respectively. These analyses were done via comparison of integral intensities from major component 13C satellites in 1H or even in 13C spectra to the 1H or 13C signals of impurities. Despite lower sensitivity, the last option generally has much better selectivity. In this way the dynamic resolution is brought down by two orders. Chirality 25:793–798, 2013. © 2013 Wiley Periodicals, Inc.  相似文献   
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69.
Disease management, a system of coordinated health care interventions and communications for chronically ill populations, relies on patient education and case management to engage individuals in the management of their condition. Disease management also aims to enhance the quality of interactions between doctors and patients and advance evidence-based medicine. Because these programs' interventions frequently include helping individuals who suffer comorbidities associated with obesity to reduce their BMI, adaptation of disease management to populations with obesity seems a viable option. A major barrier for implementing disease management for obesity, however, is the lack of proven return on investment, which limits health plan and disease management organization interest. Purchaser demand may overcome this reluctance. Further research is needed to objectively test whether disease management interventions would be clinically effective for obese populations, produce positive financial outcomes for insurers, and enhance workplace productivity.  相似文献   
70.
Plant species in fragmented populations are affected by landscape structure because persistence within and migration among inhabited patches may be influenced by the identity and configuration of surrounding habitat elements. This may also be true for species of the semi-natural vegetation in agricultural landscapes. To determine the effect of landscape elements we analyzed Wood Avens (Geum urbanum L.) populations within three 4×4 km2 agricultural landscapes in Germany, Switzerland and Estonia, which differ in levels of land use intensity and habitat fragmentation. Genetic variation was determined in 15 randomly selected populations in each landscape using 10 microsatellite loci. The landscape structure was assessed at two circles around each population, with radii defined by the range limits of spatial genetic autocorrelation. Multiple regression analysis was used to determine the influence of landscape structure variables for inter- and intrapopulation genetic diversity. Gene diversity was equally high in Germany (He=0.27) and Switzerland (He=0.26) but lower in Estonia (He=0.16). A high overall inbreeding coefficient (FIS=0.89) was found, as expected for a selfing breeding system in G. urbanum. Genetic differentiation among populations was high (overall FST=0.43, 0.48, and 0.45 in Estonia, Switzerland and Germany, respectively), and did not differ among the three landscapes. Only a moderate influence of individual land use types on genetic diversity within and among populations was found with some idiosyncratic relationships. Genetic variation within populations was correlated to the amount of hedgerows positively in Estonia but negatively in Switzerland. The study demonstrates that the distribution of individual land use types affects the genetic pattern of a common plant species. However, different variables were identified to influence the genetic structure in three different landscapes. This indicates a major influence of landscape-specific land use history and stochastic processes determining gene flow and plant population structure.  相似文献   
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