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排序方式: 共有121条查询结果,搜索用时 15 毫秒
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Beata Irena Cejko Ákos Horváth Timea Kollár Eszter Kása Jelena Lujić Zoran Marinović Béla Urbányi Radosław Kajetan Kowalski 《Fish physiology and biochemistry》2018,44(6):1435-1442
The effect of sodium and potassium concentrations as well as optimal pH on the motility of common carp Cyprinus carpio L. sperm during short-term storage in artificial seminal plasma (ASP) was investigated. Sperm was collected from individual males (n?=?5) and each sample diluted tenfold (1:9) in ASP (sperm:extender) containing 2 mM CaCl2, 1 mM Mg2SO4 and 20 mM Tris at pH 8.0 and supplemented by the following concentrations of sodium and potassium (mM/mM): 0/150, 20/130, 40/110, 75/75, 110/40, 130/20 and 150/0. The osmolality of all ASP variants was set at 310 mOsm kg?1. Sperm motility was measured using a CASA system during 72 h of storage. Immediately after dilution, sperm motility was high (90%) both in each variant and in the control group (fresh sperm). After 72-h storage, the highest sperm motility was noted in ASP containing 110 mM NaCl and 40 mM KCl. No differences were found in the motility of samples preserved within the pH range of 7.0–9.0. Our data suggest that for the short-term storage of common carp sperm, whereas the pH of the solution does not play a crucial role, a specific potassium concentration of around 40 mM is required. 相似文献
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We have shown previously that riboflavin is stored in chloragosomes of chloragocyte-derived earthworm eleocytes what may have an adaptive value for worms vulnerable to soil-derived pathogen invasion. Thus, it is important to determine whether riboflavin stores are also present in earthworm species with low eleocyte counts, especially in the chloragocytes of their chloragogen tissue that surrounds the coelomic site of the intestine, and find out its putative roles in earthworm immunity. Experiments were performed on adult worms from 6 species. Freely floating coelomocytes (consisting of amoebocytes plus species-specific numbers of eleocytes) were extruded by mild electric shock and then chloragocytes from the same anaesthetized worm were mechanically detached into buffer. Both cell suspensions were analyzed by spectrofluorometry for riboflavin content. It turned out that riboflavin is stored in species-specific quantities in all investigated species. Riboflavin storage predominates in free coelomocytes of eleocyte-rich species (Eisenia andrei, Dendrobaena veneta, Allolobophora chlorotica) while in chloragocytes of species with few eleocytes (Lumbricus terrestris, L. rubellus, and Aporrectodea caliginosa). Upon a massive microbial impact, the coelomocytes (both amoebocytes and eleocytes) are involved in the formation of multicellular bodies encapsulating soil-derived pathogens, what is connected with enhanced coelomocyte mobility. Thus the second aim of the present investigation was to check if riboflavin can participate in coelomocyte accumulations. Tests performed in a 48-well chemotaxis chamber revealed that riboflavin behave as chemoattractant for coelomocytes of all investigated earthworm species, which may be one of mechanisms underpinning its immunomodulatory functions. 相似文献
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Shrestha MK Peri I Smirnoff P Birk Y Golan-Goldhirsh A 《Journal of agricultural and food chemistry》2002,50(20):5670-5675
The jojoba, Simmondsia chinensis, is a characteristic desert plant native to the Sonoran desert. The jojoba meal after oil extraction is rich in protein. The major jojoba proteins were albumins (79%) and globulins (21%), which have similar amino acid compositions and also showed a labile thrombin-inhibitory activity. SDS-PAGE showed two major proteins at 50 kDa and 25 kDa both in the albumins and in the globulins. The 25 kDa protein has trypsin- and chymotrypsin-inhibitory activities. In vitro digestibility of the globulins and albumins resembled that of casein and soybean protein concentrates and was increased after heat treatment. The increased digestibility achieved by boiling may be attributed to inactivation of the protease inhibitors and denaturation of proteins. 相似文献
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Lech Szajdak Irena yczyska‐Baoniak Teresa Meysner Andrzej Blecharczyk 《植物养料与土壤学杂志》2004,167(5):562-567
We investigated the varying concentrations of bound amino acids in humic acids (HA) extracted from soils under both crop rotation and continuous cropping of rye. The experiment was created in 1957. Since then, winter rye had been grown continuously and also the sequence of the 7 yr rotation had been started: potato, spring barley, alfalfa, alfalfa, oil seed rape, winter rye, and winter rye. Soils were fertilized with NPK and manure. Continuous cropping of rye increased total acidity of soils and the contents of carboxylic and phenolic groups in HA. The total amounts of the bound amino acids in HA from soils under crop rotation were higher than from continuous cropping of rye. Fertilization with NPK increased the contents of bound amino acids more than manure. Neutral amino acids dominated in all samples of HA, and basic amino acids had the lowest concentrations. In both types of cultivation, glutamic acids, glycine, alanine, valine, and lysine dominated. The proline contents in HA from continuous rye cropping were higher than in HA from soils under crop rotation. The concentrations of β‐alanine and lysine were higher in HA from crop rotation indicating a higher microbial biomass since these compounds are typical constituents of bacteria cell walls. 相似文献
6.
Hilma Peusha Tamara Enno Irena Jakobson Jelena Tsotildembalova Anne Ingver 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2013,63(4):289-296
Abstract A group of spring wheat cultivars originating from Sweden, Finland, Norway, Germany, and the Netherlands was analysed for powdery mildew resistance. Using functional molecular markers, two alleles of the major resistance gene Pm3 were detected among the cultivars under the study. One of the alleles, Pm3d, was detected in the resistant cultivars ‘Vinjett’, ‘SW Estrad’, and ‘Zebra’, and in ‘Tjalve’, a cultivar of earlier release susceptible to the local population of powdery mildew. The second allele of Pm3 detected in the analysed group of cultivars was the allele Pm3f, rarely used in Europe. It was identified in the resistant cultivars ‘Satu’, ‘Helle’, and in the moderatively resistant cultivar ‘Mahti’. Pm3f was found to be effective against the local population of powdery mildew in Estonia, while Pm3d provided no protective effect. Besides the Pm3d allele on chromosome 1A, monosomic analysis of the cultivar ‘Vinjett’,which is almost immune to powdery mildew, identified two additional loci on chromosomes 5D and 7D, respectively, presumably responsible for the high resistance in this cultivar. In contrast to the earlier cultivars, six recently released cultivars (‘Vinjett’, ‘SW Estrad’, ‘Zebra’, ‘Satu’, ‘Helle’, ‘Meri’) demonstrated a high resistance to the powdery mildew fungus Blumeria graminis DC. f. sp. tritici both in the field and seedling tests, showing that the genetic basis of powdery mildew resistance in Nordic spring wheat has been improved noticeably in the last ten years. 相似文献
7.
Thibaut Olivier Vaidevutis Šveikauskas Elisabeth Demonty Kris De Jonghe Pascal Gentit Mojca Viršček-Marn Sabine Grausgruber-Gröger Sébastien Morio Francesco Faggioli Michèle Visage Frédéric Fauche Maria Gusina Marta Luigi Helena Lasner Irena Mavrič-Pleško 《European journal of plant pathology / European Foundation for Plant Pathology》2016,144(3):645-654
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Irena Pípalová 《Aquaculture International》2003,11(4):325-336
The aims of this experiment were (1) toquantify the ability of grass carp to processduckweed and (2) to assess indirect changes inwater chemistry and phytoplankton community,caused by grass carp feeding. Yearling grass carp sized 126 ± 7.7 mm (TL) and19.6 g in weight were kept in 9 laminate tanksof 1 m3 for 14 days. Two stockingdensities (2 and 6 fish per m3) anda control without fish were used. Standard growthrate (SGR) of grass carp fed exclusively onduckweed was 0.70% body weight (BW) d–1and food conversion ratio (FCR) reached 2.0(average water temperature =21.1 ± 3.8 °C). Daily food intakewas 0.2 g of duckweed dry weight (DW), i.e.,1% of average BW of grass carp. SGR ofduckweed growing in 20 × 20 cm floatingenclosures, differed significantly[F(6,2) = 417.9; p = 0.002] between the twostocking densities of grass carp and thecontrol tanks (without fish). Mean SGR ofduckweed was 0.02 g g–1 day–1 and thehighest SGR was recorded in the control tanks.Both decrease in NH4-N and increase inNO2-N concentrations differedsignificantly between the treatments[F(2,2) = 45.3; p = 0.02 and F(2,2) = 19.2; p = 0.04 respectively]. Changes in other nitrogenand phosphorus components (NO3-N, TN, TPand PO4-P) caused by stocking of grasscarp were not significant. Biomass ofphytoplankton, dominated by filamentous algaeand blue-greens, increased proportionately tostocking density of grass carp. Althoughduckweed has a large potential for nutrientremoval, the most common pathway for thenutrients released through grass carp grazingif duckweed cover is loose is theirincorporation into phytoplankton biomass. 相似文献
10.
B. Aloni Leah Karni Irena Rylski Z. Zaidman 《The Journal of Horticultural Science and Biotechnology》2013,88(4):767-773
SUMMARY“Colour spots” (CS) in pepper fruit is a physiological disorder characteristic of some sweet pepper cultivars. The symptoms are yellowish spots on the outer surface of affected fruits. We investigated the effects of shading and nitrogen supply on the susceptibility of three sweet pepper cvs (Maor, Lady Bell and 899) to CS. The most susceptible was ‘Maor’. The incidence of CS was promoted by high N and shading. The fruits of all cultivars had lower nitrogen concentrations than the leaves but there were no significant differences in fruit N content between Maor and the CS-insensitive cultivars. The CS-affected areas of the pericarp tissue had higher calcium concentrations than unaffected tissue. Differences in magnesium or potassium concentrations in these spots were less pronounced. Scanning electron microscopy revealed that the affected pericarp cells contained crystals, presumably of calcium oxalate. Only in ‘Maor’ fruits was the oxalate concentration elevated by approximately nine-fold when the nitrogen supply to shaded plants was increased. We suggest that in the fruits of the sensitive cultivar, oxalic acid production is enhanced under high-nitrogen + shading conditions and causes the CS damage, possibly be chelating intracellular calcium. 相似文献