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排序方式: 共有263条查询结果,搜索用时 15 毫秒
1.
保持饲料新鲜 ,是一个古老的话题 ,但却常常被人忽视。保育期日粮配制成以后 ,其中蛋白质和脂肪的含量并非固定不变。正确进行贮存是极为重要的 ,否则 ,饲料就会迅速发生化学变化 ,导致饲料变性从而降低其中养分的消化率 相似文献
2.
Ioannis Stergiopoulos Lute-Harm Zwiers Maarten A. De Waard 《European journal of plant pathology / European Foundation for Plant Pathology》2002,108(7):719-734
This review provides an overview of members of the ATP-binding cassette (ABC) and major facilitator superfamily (MFS) of transporters identified in filamentous fungi. The most common function of these membrane proteins is to provide protection against natural toxic compounds present in the environment of fungi, such as antibiotics produced by other microorganisms. In plant pathogenic fungi, these transporters can also be an important determinant of virulence on host plants by providing protection against plant defence compounds or mediating the secretion of host-specific toxins. Furthermore, they play a critical role in determining base-line sensitivity to fungicides and other antimycotic agents. Overexpression of some of these transporters can lead to the development of resistance to chemically-unrelated compounds, a phenomenon described as multidrug resistance (MDR). This has been observed in a variety of organisms and can impose a serious threat to the effective control of pathogenic fungi. 相似文献
3.
Ioannis Nanas Mariana Barbagianni Katerina Dadouli Eleni Dovolou Georgios S Amiridis 《Reproduction in domestic animals》2021,56(10):1329-1341
The objectives of this study were to assess alterations in, echogenic appearance, size and blood flow in the corpus luteum, the placentomes and the blood flow in umbilical and uterine arteries that heat stress can cause in cooled pregnant dairy cows. Pregnant cows were allocated in two groups and the gravid uteri, along with the ipsilateral corpora lutea were examined during the winter (group W, n = 9) or the summer (group S, n = 10). The grey-scale ultrasound and colour flow imaging of the corpus luteum and placentome were performed. In addition, the umbilical and uterine artery diameters and haemodynamic parameters in the vessels were calculated. At the time of ultrasonographic examination, cortisol concentrations were higher, and progesterone levels tended to be lower in group S compared to group W. The grey-scale ultrasound evaluation of corpora lutea and placentomes was lower in group S compared to group W. The diameter of umbilical artery and the blood volume in the vessel were less in group S than in group W. We infer that heat stress affects foetal blood supply and possibly the structure of placentomes and corpora lutea, but it differently affects the blood flow characteristics in the umbilical and uterine arteries. 相似文献
4.
Paraskevas Koumpiadis Daniela E. Sganga Sebastian N. Politis Victor Gallego Ian A. E. Butts Juan F. Asturiano Ioannis E. Batjakas Jonna Tomkiewicz 《Reproduction in domestic animals》2021,56(12):1497-1505
Aquaculture production relies on controlled management of gametogenesis, especially in species where assisted reproduction is needed for obtaining gametes in captivity. The present study used human chorionic gonadotropin (hCG) treatments to induce and sustain spermatogenesis in European eel (Anguilla anguilla). The aim was to evaluate effects of strip-spawning timing (12 vs. 24 hr) after weekly administration of hCG and the necessity of a primer dose (in addition to weekly hormonal treatment) prior to strip spawning (primer vs. no-primer) on sperm quality parameters. Sperm parameters included milt production (weight), density and sperm kinematics at Week 9, 11 and 13 after onset of treatment. Spermiation commenced in 11.5% of males in Week 5 and by Week 9, and all males produced milt. Male weight, milt production, sperm density and spermatocrit did not differ among hormonal treatments during the experimental period. Overall, male weight decreased from 106.3 to 93.0 g, milt weight increased from 3.5 to 5.4 g, sperm density counts decreased from 11.7 × 109 to 10.5 × 109 cells/ml, and spermatocrit decreased from 46.5% to 40.5%. Furthermore, spermatocrit was positively related to haemocytometer counts (R2 = .86, p < .001), providing a reliable indicator of sperm density. Differences in sperm kinematics were observed depending on strip-spawning timing after hormonal injection (12 vs. 24 hr) but with no consistent pattern. These sperm quality parameters also did not consistently differ between the no-primer and primer treatments. Considering that each male may be stripped 4–5 times over the 2–3 months spawning season, omitting the primer would reduce animal handling, material costs and labour intensity, while sustaining high-quality sperm production. 相似文献
5.
Melpomeni K. Tangalidi Ioannis L. Oikonomidis Dimitra Psalla Serafim Papadimitriou Maria Kritsepi‐Konstantinou Mathios E. Mylonakis 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2016,45(4):710-714
A 5.5‐year‐old, intact male Rottweiler dog was admitted with a history of multifocal nodular tongue lesions which progressively deteriorated during the previous year. Physical examination revealed several reddish nodules with central depression on the surface of the tongue in an otherwise healthy dog. Clinicopathologic abnormalities included eosinophilia and hyperproteinemia. Lingual nodule cytopathology, histopathology, and immunohistochemistry revealed Leishmania spp. amastigotes and a severe granulomatous glossitis. The dog was also seroreactive to L infantum antigens by an indirect immunofluorescence assay. Clinical reevaluation 3 months after the institution of treatment with allopurinol and miltefosine indicated that the nodular lesions had completely regressed. In endemic areas, lingual nodular lesions may rarely be the sole clinical sign of canine leishmaniosis. Standard medical treatment may provide an excellent prognosis. 相似文献
6.
Smaro Lykidou Evangelos Karanikas Ioannis Tsagalias Nikolaos Nikolaidis Eforia Tsatsaroni 《Fibers and Polymers》2017,18(9):1697-1707
Three new bis azo reactive dyes of different metallic salts (Na, K, Li) were synthesized. The synthesis was obtained by diazotization of 4-amino-2:5 di methoxy phenylene-beta hydroxyl ethyl sulphone sulphate ester and coupling with 1-amino-8-hydroxynaphthalene-3,6-disulfonic acid (H-acid) (moles ratio 2:1). The dyes were purified-concentrated by ultrafiltration technology, characterized and applied on cotton, wool and nylon 6,6 fabric by exhaustion (dyeing) and by ink-jet printing. Fastness properties of the dyeings were measured. Wash fastness was investigated according to international standard methods and was found to be very good to excellent in all cases, while light fastness values were medium to low. Ink-jet ink formulations were prepared using the ultra filtrated reactive blue dyes UF RB(a-c) and their properties pH, conductivity, surface tension and viscosity were monitored over a period of 90 days. The inks were used to print digitally cotton and nylon 6,6 samples and wash- and light fastness properties of the prints were measured. Wash fastness properties were excellent while light fastness values are low Colour measurements of the dyeings and prints were conducted. 相似文献
7.
George Rigos Alexandros Samartzis Morgane Henry Eleni Fountoulaki Efthimia Cotou John Sweetman Simon Davies Ioannis Nengas 《Aquaculture International》2010,18(6):1093-1104
The comparative effects of iron-supplemented levels on growth, tissue distribution, haematology and immunology of gilthead
sea bream, Sparus aurata (2 g) were investigated, using four organic (50, 100, 200, 300 mg ORG/kg diet) and one inorganic iron source (200 INOR mg/kg diet).
Fish were treated for 12 weeks with the experimental diets and maintained at a water temperature of 19–22°C. Growth (final
weight and specific growth rate), tissue distribution (spleen, liver and muscle), haematological parameters (red blood cells,
haematocrit, haemoglobin and mean corpuscular haemoglobin concentration) and non-specific immune indexes (respiratory burst
activity and antibacterial activity of serum) were analysed. No significant differences were found in growth and iron tissue
distribution among the tested groups. Red blood cell counting was statistically higher in fish given 50 ORG, 100 ORG, 200
ORG and 200 INOR feeds. However, haematocrit, haemoglobin and mean corpuscular haemoglobin concentration were not significantly
affected by increasing dietary iron. Fish receiving the 100 ORG diet had the best performance with respect to the respiratory
burst activity and significantly higher values for antibacterial activity of serum were obtained in fish fed with the 300
ORG diet. The present findings provided no clear evidence of the optimum iron concentration. However, there was adequate indication
that iron supplementation enhanced the performance of gilthead sea bream, mainly from a haematological and immunological point
of view. 相似文献
8.
9.
Aligiannis N Mitaku S Tsitsa-Tsardis E Harvala C Tsaknis I Lalas S Haroutounian S 《Journal of agricultural and food chemistry》2003,51(25):7308-7312
The antioxidant properties of various fractions of a methanolic extract obtained from the aerial parts of Verbascum macrurum have been determined by monitoring their capacity to scavenge the stable free-radical DPPH. They were also evaluated as natural preservatives against oxidative rancidity using the accelerated Rancimat method. Their activities expressed as protection factor (PF(r)) indicated that the fractions rich with phenylpropanoid glycosides were more potent compared to alpha-tocopherol and of the same magnitude as BHT, which were used as reference standards. Ten natural compounds were identified as components of this methanolic extract and were isolated by medium-pressure liquid chromatography (MPLC). Assessment of their antioxidant activities established that acteoside, a polyhydroxylated phenylpropanoid glycoside derivative, is the most potent free radical scavenger and showed the highest protection factor (PF(r)) against sunflower-oil-induced oxidative rancidity. Its activity is comparable to the synthetic antioxidant BHT and clearly superior to natural alpha-tocopherol. This compound therefore represents a very interesting candidate for use in food preservation as natural protecting agent against oxidative rancidity. 相似文献
10.
The distribution of olive fruit fly captures with McPhail traps within an olive orchard 总被引:1,自引:0,他引:1
Ioannis?DimouEmail author Constantin?Koutsikopoulos Aristidis?Economopoulos Josef?Lykakis 《Phytoparasitica》2003,31(2):124-131
The spatial distribution of olive fruit flyBactrocera (Dacus) oleae (Gmelin) (Diptera: Tephritidae) field captures with McPhail traps within an experimental orchard was evaluated. Contour maps
were constructed to examine the patterns in the 3-year trapping data. Captures varied widely inside the olive orchard, with
traps suspended on wild olive trees exhibiting the poorest performance. Favorable microclimate, created by a standing water
pool, appeared to be responsible for increased trap captures during the hot summer months. The positive role of the olive
tree fruit load is also discussed.
http://www.phytoparasitica.org posting Feb. 2, 2003. 相似文献