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排序方式: 共有455条查询结果,搜索用时 15 毫秒
91.
Effect of selection for growth rate on biochemical, quality and texture characteristics of meat from rabbits 总被引:2,自引:0,他引:2
Ramírez JA Oliver MÀ Pla M Guerrero L Ariño B Blasco A Pascual M Gil M 《Meat science》2004,67(4):617-624
Biochemical characteristics, including myosin heavy chain I (MHC-I) percentage, isocitrate dehydrogenase and aldolase activities, meat quality traits and instrumental texture properties of rabbits selected for different growth rates were studied. The animals of the control (C) group (7th generation; n=60) were raised in parallel with those of selection (S) group (21st generation; n=60). Carcass weights (1230.1 ± 19.8 and 1348.3 ± 20.1 g, for C and S, respectively) and perirenal and scapular fat content differed significantly (P<0.01) between the two groups. Water holding capacity was expressed as the percentage of pressure released water and was significantly different (P<0.05) between groups C and S (33.29% and 35.57%). MHC-I percentage and aldolase activity also differed significantly (P<0.05) between groups, group C showing higher oxidative traits than group S (MHC-I: 12.5% and 9.8%; aldolase: 597.11 and 636.83 UI/g muscle). Texture properties from the Warner-Bratzler test showed higher (P<0.001) shear firmness for loin in the S group (1.69 kg/s cm2) than in the C group (1.34 kg/s cm2). In addition, the texture profile analysis indicated that chewiness, gumminess and hardness were also higher in the S group (P<0.01). In conclusion, the results confirmed a positive effect of the selection on productive traits and a negative effect on instrumental texture properties and on the water holding capacity of the meat. 相似文献
92.
Janne Pesonen Toivo Kuokkanen Erik Kaipiainen Juha Koskela Iina Jerkku Ari Pappinen Aki Villa 《Holz als Roh- und Werkstoff》2014,72(6):769-777
The European Union’s growth strategy (Europe 2020) requires reductions in greenhouse gas (GHG) emissions and increases in both renewable energy sources and energy efficiency. Short rotation forestry (SRF) has achieved greater awareness due to these targets. Short rotations (1–12 years), rapid growth and the ability to coppice are typical for SRF. Salix, Populus, Alnus and Betula have smaller GHG emissions of biomass production than annual agricultural plant species, since management and harvesting are not needed every year. Physicochemical properties of these species must be known when their utilisation is planned and optimised. Seven tree species were studied: three willows (Salix myrsinifolia, Salix schwerinii and Klara), one aspen (Populus tremula), one alder (Alnus glutinosa) and two birches (Betula pendula and Betula pubescens). One stem wood (S) sample and one stem wood and bark (SB) sample of each tree were investigated. Furthermore, seven surface soil samples and four incineration ash samples (two S. myrsinifolia and two S. schwerinii) were also studied. Heating values, densities, ash contents as well as carbon, hydrogen and nitrogen contents of all short rotation biomass samples were usually quite typical for the corresponding tree species. Additional observations included the accumulation of cadmium in willow and aspen samples, small chloride content values, and higher ash- and element contents in SB samples than in the corresponding S samples. Nutrient content of ash was usually higher in the S sample, contradictory to biomass samples, and finally the cadmium content of the ash samples was very high. 相似文献
93.
Lyes Tabet Cyrill Bussy Ari Setyan Angélique Simon-Deckers Michel J Rossi Jorge Boczkowski Sophie Lanone 《Particle and fibre toxicology》2011,8(1):3
Background
carbon nanotubes (CNT) can have adverse effects on health. Therefore, minimizing the risk associated with CNT exposure is of crucial importance. The aim of this work was to evaluate if coating multi-walled CNT (MWCNT) with polymers could modify their toxicity, thus representing a useful strategy to decrease adverse health effects of CNT. We used industrially-produced MWCNT uncoated (NT1) or coated (50/50 wt%) with acid-based (NT2) or polystyrene-based (NT3) polymer, and exposed murine macrophages (RAW 264.7 cell line) or Balb/c mice by intratracheal administration. Biological experiments were performed both in vitro and in vivo, examining time- and dose-dependent effects of CNT, in terms of cytotoxicity, expression of genes and proteins related to oxidative stress, inflammation and tissue remodeling, cell and lung tissue morphology (optical and transmission electron microscopy), and bronchoalveolar lavage fluid content analysis. 相似文献94.
Karkkainen K. Sihvola A. Nikoskinen K. 《Geoscience and Remote Sensing, IEEE Transactions on》2001,39(5):1013-1018
The present paper reports the results of a numerical analysis of electric fields in random dielectric materials. The effective permittivity of a three-dimensional (3D) dielectric mixture is calculated by the finite difference method. The results show the distribution of the effective permittivity of a mixture with different random inclusion positionings. New empirical mixing models are created as least squares approximations to fit the collection of numerical results. The calculated permittivity distribution is also compared with theoretical mixture models, showing that in case of clustered inclusions, the Bruggeman model is quite reasonable. On the other hand, if the inclusions in the mixture are separate, the results are closer to the Maxwell-Garnett model 相似文献
95.
Natasja Leth Bergholt Ari Demirel Michael Pedersen Ming Ding Tue Wenzel Kragstrup Thomas Andersen Bent Winding Deleuran Casper Bindzus Foldager 《International journal of molecular sciences》2022,23(1)
Systemic Intermittent Hypoxic Therapy (IHT) relies on the adaptive response to hypoxic stress. We investigated allogenic bone-graft resorption in the lumbar spine in 48 mice. The mice were exposed to IHT for 1 week before surgery or 1 week after surgery and compared with controls after 1 and 4 weeks. Complete graft resorption was observed in 33–36% of the animals in the control group, but none in the preoperative IHT group. Increased bone-graft volume was demonstrated by micro-computed tomography in the preoperative IHT group after 1 week (p = 0.03) while a non-significant difference was observed after 4 weeks (p = 0.12). There were no significant differences in the postoperative IHT group. Increased concentration of immune cells was localized in the graft area, and more positive tartrate-resistant acid phosphatase (TRAP) staining was found in controls compared with IHT allogenic bone grafts. Systemic IHT resulted in a significant increase of the major osteoclast inhibitor osteoprotegerin as well as osteogenic and angiogenic regulators Tgfbr3, Fst3l, Wisp1, and Vegfd. Inflammatory cytokines and receptor activator of nuclear factor kappa-B ligand (RANKL) stimulators IL-6, IL-17a, IL-17f, and IL-23r increased after 1 and 4 weeks, and serum RANKL expression remained constant while Ccl3 and Ccl5 decreased. We conclude that the adaptive response to IHT activates numerous pathways leading to inhibition of osteoclastic activity and inhibition of allogenic bone-graft resorption. 相似文献
96.
Tama Dinur Peter Bauer Christian Beetz Guido Kramp Claudia Cozma Marius-Ionu Iuracu Michal Becker-Cohen Majdolen Istaiti Arndt Rolfs Ari Zimran Shoshana Revel-Vilk 《International journal of molecular sciences》2022,23(3)
For years, the gold standard for diagnosing Gaucher disease (GD) has been detecting reduced β-glucocerebrosidase (GCase) activity in peripheral blood cells combined with GBA1 mutation analysis. The use of dried blood spot (DBS) specimens offers many advantages, including easy collection, the need for a small amount of blood, and simpler transportation. However, DBS has limitations for measuring GCase activity. In this paper, we recount our cross-sectional study and publish seven years of experience using DBS samples and levels of the deacylated form of glucocerebroside, glucosylsphingosine (lyso-Gb1), for GD diagnosis. Of 444 screened subjects, 99 (22.3%) were diagnosed with GD at a median (range) age of 21 (1–78) years. Lyso-Gb levels for genetically confirmed GD patients vs. subjects negative to GD diagnosis were 252 (9–1340) ng/mL and 5.4 (1.5–16) ng/mL, respectively. Patients diagnosed with GD1 and mild GBA1 variants had lower median (range) lyso-Gb1, 194 (9–1050), compared to GD1 and severe GBA1 variants, 447 (38–1340) ng/mL, and neuronopathic GD, 325 (116–1270) ng/mL (p = 0.001). Subjects with heterozygous GBA1 variants (carrier) had higher lyso-Gb1 levels, 5.8 (2.5–15.3) ng/mL, compared to wild-type GBA1, 4.9 (1.5–16), ng/mL (p = 0.001). Lyso-Gb1 levels, median (range), were 5 (2.7–10.7) in heterozygous GBA1 carriers with Parkinson’s disease (PD), similar to lyso-Gb1 levels in subjects without PD. We call for a paradigm change for the diagnosis of GD based on lyso-Gb1 measurements and confirmatory GBA1 mutation analyses in DBS. Lyso-Gb1 levels could not be used to differentiate between heterozygous GBA1 carriers and wild type. 相似文献
97.
Betul Ari Berkant Yetiskin Oguz Okay Nurettin Sahiner 《Polymer Engineering and Science》2020,60(8):1890-1901
We present mechanically strong macroporous, squeezable dextran cryogels as a column filling material for the removal and separation of binary organic dye and pesticide mixtures from aquatic medium. Dextran cryogels were prepared from aqueous solutions of dextran of various molecular weights (MWs) in the presence of 20 to 50 mol% divinyl sulfone (DVS) as a cross-linker at −18°C. The cryogels have interconnected irregular pores of 100 μm in sizes, and exhibit 69-84% reversible squeezability without damaging the 3D dextran network. Their total open pore volumes (6.3-10 mL g−1), weight swelling ratios in water (1380%-2200%), and mechanical parameters could easily be adjusted by both DVS mol% and MW of dextran. Dextran cryogel with the highest modulus (3.8 ± 0.5 MPa), compressive stress (8 ± 2 MPa) and plateau stress (0.46 ± 0.04 MPa) was obtained at 50 mol% DVS using dextran with a MW of 15 to 25 kg·mol−1. Dextran cryogels are hydrolysable at pH = 1 and 9 but stable at 7.4 independent on both the degree of cross-linking and MW of dextran. At below 50 mol% DVS, they are blood compatible and possess slight thrombogenic effect with blood clotting index value of 98% ± 5%. They are also capable to separate binary dye and pesticide mixtures from aqueous solutions via ionic interactions. 相似文献
98.
99.
100.
Through microcalorimetric experiments, disperse order (DO) dissolution kinetics in preannealedα-Cu-Al alloys containing 19, 13 and 6.5 at % aluminium were adequately described by the integrated kinetic model function
arising from the steady-state part of the diffusion field:f(y)=1 − (1−y) 2/3. Domain sizes after the annealing treatment, and also critical radii, were determined from differential scanning calorimetry
data analysis at different heating rates. The existence of critical radii indicates that the disperse-order dissolution process
is a first-order transition. Nevertheless, it was inferred that for very dilute alloys, only short-range order is present.
After pre-annealing the alloys at different temperatures, volume fractions and domain concentrations were computed by employing
the above kinetic model under high heating-rate conditions. On the basis of appropriate time constant and diffusion time calculations,
the range of such temperatures compatible with equilibrium attainment was established. Prolonged pre-anneals alter the particle
distribution, but do not influence either volume fractions or domain sizes. A semi-quantitative particle radius-particle concentration-temperature
diagram was proposed forα-Cu-Al alloys. 相似文献