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排序方式: 共有166条查询结果,搜索用时 187 毫秒
91.
92.
Vlasta Jankovská 《Biologia》2006,61(20):S371-S385
Pollen analysis has been carried out on a 549 cm thick sediment profile from lake Ple?né jezero (Ple?né Lake) in the Bohemian Forest (?umava, Czech Republic; 1090 m a.s.l.; 48°47′ N; 13°52′ E). Analyses of 67 samples characterise the development of the lake biotope and the surrounding landscape during the last ca. 14,000 years. The pollen diagram shows a very distinct transition between the Late Glacial and the Holocene biostratigraphic units at a depth of ca. 312 cm. In the surroundings of Ple?né Lake the vegetation was treeless during the entire Late Glacial. The alpine tree limit, formed by Betula and Pinus with undergrowth of shrubs, might have been at ca. 500 m a.s.l. Pollen transported from long distances was significant due to the openness of the landscape, coming from southern Europe and even Africa, and including high numbers of Artemisia, Poaceae, Chenopodiaceae, and some other herbs and shrubs from steppe and forest-steppe areas in southern Europe or Africa (likely Ephedra, certainly Lygeum spartum). The expansion of shrubs, particularly Juniperus, preceded the expansion of trees near the end of the Late Glacial. Afforestation of the region by thin stands of Betula and Pinus occurred during the Preboreal. Significant warming in the Boreal resulted in the expansion of Corylus, Quercetum mixtum (QM) trees, and probably also Picea and Alnus. Picea as well as QM trees were further expanding during the Early Atlantic. Picea was the dominant tree during the Late Atlantic and Fagus started to spread towards its end. Abrupt expansion of Abies marks the Subboreal. A high degree of afforestation (Abies, Fagus, Picea) was characteristic for the Early Subatlantic. During Late Subatlantic, pollen of synanthropic plants appears. Phases of the lake biotope development were defined on the basis of coccal green algae and Isoëtes. 相似文献
93.
Horvat D Grman-Fanfani A Kupres V Grman J Sporcić-Jelić V 《Collegium antropologicum》2008,32(1):99-102
To determine in acute myocardial infarction with an ST elevation (STEMI) treated with fibrinolytics frequency of ventricular premature beats (VPBs) and ventricular tachycardia (VT) according to the damaged area and residual cardiac function. With anterolateral infarction with ejection fraction (EF) < 45%, incidence of VPBs < 10/h was statistically significantly reduced (p < 0.001) while incidence of VPBs > or = 10/h as well as VPBs in a pair and VT was increased (p < 0.001). With anteroseptal infarction with EF < 45%, incidence of VPBs < 10/h was statistically reduced (p = 0.06) and incidence of VPBs > 10/h, VPBs in a pair and VT was increased (p = 0.06). With inferior and inferoposterior infarction with EF < 45%, incidence of VPBs < 10/h was reduced and incidence of VPBs > or = 10/h, VPBs in a pair and VT was increased. However, such difference was not statistically significant. Along with reduced residual cardiac function, one can also expect increase in frequency of VPBs and VT in all forms of STEMI regardless the area of damage. Such frequency is significant with all forms of anterior infarction, that is to say, slightly more with anterolateral infarction in relation to anteroseptal one. However, with inferior and inferoposterior infarction this frequency of VPBs i VT is not significant. 相似文献
94.
Rossner P Svecova V Milcova A Lnenickova Z Solansky I Sram RJ 《Mutation research》2008,642(1-2):14-20
We investigated the seasonal variability of 8-oxodeoxyguanosine (8-oxodG), a marker of oxidative damage to DNA, in urine of 50 bus drivers and 50 controls in Prague, Czech Republic, in three seasons with different levels of air pollution: winter 2005, summer 2006 and winter 2006. The exposure to environmental pollutants (carcinogenic polycyclic aromatic hydrocarbons, c-PAHs, particulate matter (PM), and volatile organic compounds (VOC)) was monitored by personal and/or stationary monitors. For the analysis of 8-oxodG levels, the ELISA technique was used. Bus drivers were exposed to significantly higher levels of c-PAHs in winter 2006, while in the other two seasons the exposure of controls was unexpectedly higher than that of bus drivers. We did not see any difference in VOC exposure between both groups in summer 2006 and in winter 2006; VOC were not monitored in winter 2005. 8-OxodG levels were higher in bus drivers than in controls in all seasons. The median levels of 8-oxodG (nmol/mmol creatinine) in bus drivers vs. controls were as follows: winter 2005: 7.79 vs. 6.12 (p=0.01); summer 2006: 6.91 vs. 5.11 (p<0.01); winter 2006: 5.73 vs. 3.94 (p<0.001). Multivariate logistic regression analysis identified PM2.5 and PM10 levels, measured by stationary monitors during a 3-day period before urine collection, as the only factors significantly affecting 8-oxodG levels, while the levels of c-PAHs had no significant influence. 相似文献
95.
Sleep after an inert capsule was compared with sleep after a hot, bedtime, milk-cereal drink (Horlicks). All-night electrophysiological recordings were made with 18 persons on 10 nights each.Restlessness during sleep at the end of the night was diminished after Horlicks in a group of 10 young adults. In an older group of eight adults, mean age 55 years, sleep after Horlicks was of longer total duration and was less broken by periods of wakefulness. In the latter group the improvement associated with Horlicks was most apparent late in the night and it increased with repeated administration. 相似文献
96.
During the pollen analyses of Bohemian peat and limnic sediments numerous empty cell walls of some chlorococcal algae, particulary, of the genusPediastrum, were found. This material was taxonomically determined and the ecology of different taxa was reconstructed and compared with the present one. The greatest difference was found inPediastrum integrum andP. kauraiskyi occurring commonly in Central Europe in the lakes during the Late-Glacial and Postglaciíal Periods but very rarely at present. Our results were compared with some data given in the literature. 相似文献
97.
Mira Kovačević Jelena Burazin Hrvoje Pavlović Mirela Kopjar Vlasta Piližota 《World journal of microbiology & biotechnology》2013,29(4):707-712
Minimally processed and refrigerated vegetables can be contaminated with Listeria species bacteria including Listeria monocytogenes due to extensive handling during processing or by cross contamination from the processing environment. The objective of this study was to examine the microbiological quality of ready-to-eat minimally processed and refrigerated vegetables from supermarkets in Osijek, Croatia. 100 samples of ready-to-eat vegetables collected from different supermarkets in Osijek, Croatia, were analyzed for presence of Listeria species and Listeria monocytogenes. The collected samples were cut iceberg lettuces (24 samples), other leafy vegetables (11 samples), delicatessen salads (23 samples), cabbage salads (19 samples), salads from mixed (17 samples) and root vegetables (6 samples). Listeria species was found in 20 samples (20 %) and Listeria monocytogenes was detected in only 1 sample (1 %) of cut red cabbage (less than 100 CFU/g). According to Croatian and EU microbiological criteria these results are satisfactory. However, the presence of Listeria species and Listeria monocytogenes indicates poor hygiene quality. The study showed that these products are often improperly labeled, since 24 % of analyzed samples lacked information about shelf life, and 60 % of samples lacked information about storage conditions. With regard to these facts, cold chain abruption with extended use after expiration date is a probable scenario. Therefore, the microbiological risk for consumers of ready-to-eat minimally processed and refrigerated vegetables is not completely eliminated. 相似文献
98.
Camptothecin (CPT) is an anticancer drug that inhibits topoisomerase I (Topo I) by forming a ternary DNA-CPT-Topo I complex.
However, it has also been shown that UVA-irradiated CPT in the absence of Topo I produces significant DNA damage to cancer
cells. In this work, we explored and identified free radicals generated in these processes. From the low-temperature EPR spectrum
of Cu(II)-CPT complex, a proximity between Cu(II) ion and 20-hydroxy group of lactone E ring of CPT is proposed. Upon irradiation
(λ = 365 nm) of the Cu(II)-CPT complex in de-oxygenated dimethylsulfoxide (DMSO), the EPR signal of Cu(II) measured in situ
at room temperature shows formal first-order exponential decay with a formal half-life of 11 min. By the use of a specific
Cu(I) chelating agent, neocuproine, it was shown that, during this process, Cu(II) is reduced to Cu(I). The loss in EPR signal
intensity of the Cu(II)-CPT complex upon irradiation is accompanied by the appearance of a new EPR signal at g ≈ 2.0022. Application of the spin trap nitrosodurene (ND) revealed that the main radical product formed upon continuous irradiation
of CPT in DMSO solutions is the hydroxyl radical (trapped in DMSO as the •CH3 adduct) and superoxide radical. Application of 2,2,6,6-tetramethyl-4-piperidinol has revealed that irradiation of CPT in
aerated DMSO solution also leads to formation of singlet oxygen (1O2). Our spectroscopic experiments indicate that CPT is a promising photosensitizer and that radicals and singlet oxygen generated
upon illumination play a central role in DNA cleavage and in the induction of apoptosis in cancer cells. 相似文献
99.
Jakeline Trejos Jiménez Maria Sturdíková Vlasta Brezová Emil Svajdlenka Marta Novotová 《Journal of microbiology (Seoul, Korea)》2012,50(6):1014-1023
Streptomyces mediolani sp. AC37 was isolated from the root system of higher plant Taxus baccata and produced metabolite identified as (?)-8-O-methyltetrangomycin according to LC/MS/MS analysis. In our screening program for improvements of bioactive secondary metabolites from plant associate streptomycetes, mutation was used as a tool for the induction of genetic variations for selection of higher (?)-8-O-methyltetrangomycin producers of isolates. S. mediolani sp. AC37 was treated with UV irradiation and chemical mutagenic treatment (N-nitroso-N-methyl-urea). The radical scavenging and antioxidant capacity of (?)-8-O-methyltetrangomycin and extracts isolated from mutants were tested using EPR spin trapping technique and ABTS·+ assay. Comparison of electron microscopic images of Streptomyces sp. AC37 and mutant strains of Streptomyces sp. AC37 revealed substantial differences in morphology and ultrastructure. 相似文献
100.
Uhernik AI Vuletić S Kern J Decković-Vukres V Mihel S Erceg M Pristas I 《Collegium antropologicum》2012,36(Z1):3-7
Health interview surveys are important source of health information. All previous adult population-based health interview surveys in Croatia until CroHort, were one-off projects with very limited possibility of data comparison. CroHort enabled repeated survey of CAHS 2003 respondents with almost identical questionnaire, thus providing comparable data on trends of different risk factors as well as their relation to the specific outcomes. Next follow-up survey of the CroHort cohort is foreseen for 2013. Health interview survey according to Eurostat methodology (EHIS) on the new representative sample of adult Croatian population is planned for 2014. As the data from health interview surveys are valuable in health policy, efforts should be made to increase their use by policymakers in Croatia. 相似文献