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141.
Enzymatic synthesis of two lacto-N-neohexaose-related Lewis x heptasaccharides and their separation by chromatography on 总被引:3,自引:2,他引:1
Natunen Jari; Niemel Ritva; Penttil` Leena; Seppo Antti; Ruohtula Terfai; Renkonen Ossi 《Glycobiology》1994,4(5):577-583
Radiolabelled lacto-N-neohexaosc was fucosylated with partiallypurified 相似文献
142.
Kaartinen Liisa Salonen Eeva–Marjatta Vaheri Antti Sandholm Markus 《Acta veterinaria Scandinavica》1988,29(3-4):485-491
Milk and whey samples from healthy and inflamed udder quarters of 10 Ayrshire cows were analyzed for proteolytic activity using radial caseolysis procedures, a fluorogenic coumaryl peptide substrate, and casein agarose zymography. Free lysosomal enzyme activity (N–acetyl–beta–D–glucosaminidase) was used as the criterion for inflammation. All mastitic milk samples had proteolytic activity, tentatively identified as plasmin (comigration at Mr 83 000 and characteristic fragmentation). The plasmin activities in mastitic milk were on average 2.9 μg/ml (range 0.5–12.5) as measured by radial caseolysis. Milk or whey specimens from healthy quarters were all negative except 1 in which an activity of 0.1 μg/ml was found in both specimens. The caseolytic activities were totally inhibited by 50 KITJ/ml of aprotinin, a serine proteinase inhibitor from bovine lung. No free plasminogen activator (PA) activity was found in any of the samples. Howewer, according to zymographic analyses PA molecules corresponding to urokinase were found in healthy and especially in mastitic specimens. Analysis of plasmin may provide an alternative means of screening for mastitic milk samples. 相似文献
143.
144.
Jussi Kuusipalo Gran djers Yusuf Jafarsidik Antti Otsamo Kari Tuomela Risto Vuokko 《植被学杂志》1995,6(2):205-210
Abstract. Reclamation of former, degraded forest lands occupied by Imperata cylindrica is one of the crucial environmental and forestry issues in the humid tropics, notably Southeast Asia. We suggest that it is possible to gradually restore the original natural forest cover with the help of a sacrifice fallow crop of fast-growing exotic tree species. Recently, a set of suitable fast-growing plantation tree species has been identified and stand establishment methods developed for this purpose. We assessed the regeneration of natural vegetation in stands of different plantation tree species and evaluated the ecological impact of species composition in the plantation understorey. PCA ordination, regression analysis and analysis of covariance were applied at different stages of the study. We found a marked vegetational resemblance between stands dominated by Acacia mangium: they had the highest number of indigenous trees in their understorey, whereas stands of other plantation trees supported more diverse grass and herb vegetation. A high proportion of evergreen woody vegetation reduces the risk of fire and grass competition and enhances secondary succession towards natural forest. 相似文献
145.
Antti Oksanen Kjetil Åsbakk Mauri Nieminen Harri Norberg Anu Näreaho 《Parasitology international》1997,46(4):255-261
To measure the prevalence of antibodies against Toxoplasma gondii in Fennoscandian reindeer, we examined 2577 serum samples collected between 1993 and 1996 from slaughtered reindeer from Finnmark county, Norway, and from several locations in Finland. The overall prevalence in this sample was 0.9%, and the titres of the seropositives in the Direct Agglutination Test (DAT) were between 1:40 and 1:162000. Logistic regression associated seropositivity with the age of the animal, the odds ratio (OR) of adults was four when compared with calves. Seropositivity was also positively associated with corral feeding, which was used in the analysis as an indicator of domestication. No significant association was found with sex, or the frost sum of the pasture area. 相似文献
146.
Emma Ojala Ville Uusitalo Terhi Virkki-Hatakka Antti Niskanen Risto Soukka 《The International Journal of Life Cycle Assessment》2016,21(8):1092-1105
Purpose
The Product Environmental Footprint (PEF) method was launched by the European Commission to harmonize the measurement of the product’s environmental performance. The PEF aims to increase the supply of green products in EU markets by lowering the cost of measuring the product’s environmental performance, enabling reliable environmental claims, and conducting proper product comparison. This study assesses whether the methodological choices of PEF enable reliable and comparable PEF studies to be conducted in a cost-efficient way.Methods
The PEF was compared with ISO 14044, ISO/TS 14067, and the Greenhouse Gas Protocol Product Standard to identify the differences in the methodological choices. From a practical perspective, the possible challenges for PEF that could not be identified by a method comparison were obtained via interviews. The interviewees were company representatives participating in a 3-year PEF pilot phase to create Product Environmental Footprint Category Rules (PEFCR). To discover the possible advantages and disadvantages of the PEF, the methodological choices for PEF itself were assessed from the standpoints of reliability, comparability, and cost. In conclusion, some proposals for improvements have been suggested.Results and discussion
The impact assessment phase, i.e., some of the predefined impact assessment methods, together with a selected normalization method include disadvantages as regards reliability and comparability. They are not sufficiently mature to properly reflect both the product studied and its potential environmental impact. From a cost perspective, the inventory analysis phase increases the workload due to the cutoff ban, the numerous predefined impact assessment categories, and the data quality assessment of all data. However, the predefined issues, e.g., requirements for data quality to be determined in PEFCRs, could also increase the comparability and lower the costs of the PEF study, since these need not be determined separately for each study. Additionally, the reliability maybe increased due to the data quality assessment of all data.Conclusions
Currently, in the PEFs 3-year pilot phase, both advantages and disadvantages exist as regards reliability, costs, and comparability. Since PEF aims are important, the Commission and PEFCR developers should devote time to finding the most appropriate methodological choices and continue developing the method further. It is important to find a balance between comparability, reliability, and costs. Additionally, the current issues and characteristics of EU green products market should be taken into account when implementing PEF.147.
Impaired ecosystems are converted back to natural ecosystems or some other target stage by means of restoration and management. Due to their agricultural legacy, afforested fields might be valuable compensatory habitats for rare fungal species that require nutrient‐rich forest soils. Using a large‐scale field experiment in Finland, we studied community composition of macrofungi (agarics and boletes) on former fields, which had been afforested as monocultures 20 years ago using native spruce Picea abies, pine Pinus sylvestris, and birch Betula pendula. We studied the effect of soil quality, tree species, and site on community composition and structure. Many nutrient‐demanding as well as rare fungal species were recorded, particularly from pine and spruce plots. Pine plots supported more nutrient‐demanding fungi than birch plots. There was no relationship between soil pH, bulk density, P, N, or Ca, and species richness of nutrient‐demanding fungi. Fungal community composition was more similar within sites than among sites for all tree species. Among sites, spruce plots had the smallest fungal species turnover, and birch plots largest. Within sites, however, fungal species turnover from plot to plot was similar among tree species. Our results indicate that tree species has a relatively mild influence on species composition of fungi after 20 years of succession. Interestingly, the results show that afforested fields can be valuable complementary habitats for rare, red‐listed, and nutrient‐demanding fungal species. Field afforestation is a potential conservation tool that could be used to complement the poor representation of rare habitat types in highly fragmented protected area networks. 相似文献
148.
Shraddha Shukla Anil Kumar Verma Ilkka Kajala Antti Nyyssolä Rwivoo Baruah Kati Katina 《Preparative biochemistry & biotechnology》2016,46(8):822-832
The dextransucrase gene from Weissella confusa Cab3, having an open reading frame of 4.2?kb coding for 1,402?amino acids, was amplified, cloned, and expressed in Lactococcus lactis. The recombinant dextransucrase, WcCab3-rDSR was expressed as extracellular enzyme in M17 medium with a specific activity of 1.5?U/mg which after purification by PEG-400 fractionation gave 6.1?U/mg resulting in 4-fold purification. WcCab3-rDSR was expressed as soluble and homogeneous protein of molecular mass, approximately, 180?kDa as analyzed by SDS-PAGE. It displayed maximum enzyme activity at 35°C at pH 5.0 in 50?mM sodium acetate buffer. WcCab3-rDSR gave Km of 6.2?mM and Vm of 6.3?µmol/min/mg. The characterization of dextran synthesized by WcCab3-rDSR by Fourier transform infrared and nuclear magnetic resonance spectroscopic analyses revealed the structural similarities with the dextran produced by the native dextransucrase. The modeled structure of WcCab3-rDSR using the crystal structures of dextransucrase from Lactobacillus reuteri (protein data bank, PDB id: 3HZ3) and Streptococcus mutans (PDB id: 3AIB) as templates depicted the presence of different domains such as A, B, C, IV, and V. The domains A and B are circularly permuted in nature having (β/α)8 triose phosphate isomerase-barrel fold making the catalytic core of WcCab3-rDSR. The structure superposition and multiple sequence alignment analyses of WcCab3-rDSR with available structures of enzymes from family 70 GH suggested that the amino acid residue Asp510 acts as a nucleophile, Glu548 acts as a catalytic acid/base, whereas Asp621 acts as a transition-state stabilizer and these residues are found to be conserved within the family. 相似文献
149.
Jari E. Kaikkonen Petri Kresanov Markku Ahotupa Antti Jula Vera Mikkilä Jorma S. A. Viikari 《Free radical research》2016,50(4):396-404
Oxidative reactions are thought to play a role in the inflammatory condition called fatty liver. It is unclear whether oxidized lipoprotein lipids or proteins are associated with future fatty liver. In the Cardiovascular Risk in Young Finns Study, we determined the circulating levels of LDL and HDL oxidized lipids and studied their associations with fatty liver assessed by ultrasonography. There were 1286 middle-aged subjects with normal liver and 288 subjects with fatty liver. Analysis of oxidized lipids consisted of conjugated dienes in isolated HDL (oxHDLlipids) and LDL (oxLDLlipids). Oxidized LDL was also measured with a method based on antibodies against oxidized apolipoprotein B (oxLDLprot). After adjustment for age, sex, leisure-time physical activity, body mass index, alcohol intake, smoking, serum LDL and HDL cholesterol as well as particle concentrations, participants with elevated oxLDLlipids (odds ratio for 1-SD change in oxLDLlipids?=?1.27, p?=?0.011) had an increased risk for fatty liver. Similarly, a high oxidation score (oxLDLlipids?+?oxLDLprot) was directly associated with fatty liver (odds ratio=1.34, p?=?0.012). The strongest direct association was seen with a high oxLDLlipids/oxHDLlipids ratio (odds ratio=1.49, p?=?0.001). These data suggest that oxidized lipoprotein lipids are linked with the risk of fatty liver in middle-aged adults. 相似文献
150.
Juho Pirhonen Johanna Arola Sanja S?devirta Panu Luukkonen Sanna-Maria Karppinen Taina Pihlajaniemi Antti Isom?ki Mika Hukkanen Hannele Yki-J?rvinen Elina Ikonen 《PloS one》2016,11(1)