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排序方式: 共有418条查询结果,搜索用时 609 毫秒
51.
Oualid Haddad Erwan Guyot Nicolas Marinval Fabien Chevalier Lo?c Maillard Latifa Gadi Christelle Laguillier-Morizot Olivier Oudar Angela Sutton Nathalie Charnaux Hanna Hlawaty 《Marine drugs》2015,13(11):6588-6608
Induction of angiogenesis is a potential treatment for chronic ischemia. Low molecular weight fucoidan (LMWF), the sulfated polysaccharide from brown seaweeds, has been shown to promote revascularization in a rat limb ischemia, increasing angiogenesis in vivo. We investigated the potential role of two heparan sulfate (HS) metabolism enzymes, exostosin-2 (EXT2) and heparanase (HPSE), and of two HS-membrane proteoglycans, syndecan-1 and -4 (SDC-1 and SDC-4), in LMWF induced angiogenesis. Our results showed that LMWF increases human vascular endothelial cell (HUVEC) migration and angiogenesis in vitro. We report that the expression and activity of the HS-degrading HPSE was increased after LMWF treatment. The phenotypic tests of LMWF-treated and EXT2- or HPSE-siRNA-transfected cells indicated that EXT2 or HPSE expression significantly affect the proangiogenic potential of LMWF. In addition, LMWF increased SDC-1, but decreased SDC-4 expressions. The effect of LMWF depends on SDC-4 expression. Silencing EXT2 or HPSE leads to an increased expression of SDC-4, providing the evidence that EXT2 and HPSE regulate the SDC-4 expression. Altogether, these data indicate that EXT2, HPSE, and SDC-4 are involved in the proangiogenic effects of LMWF, suggesting that the HS metabolism changes linked to LMWF-induced angiogenesis offer the opportunity for new therapeutic strategies of ischemic diseases. 相似文献
52.
Sylwia Magdalena Okoń Maria Chrząstek Krzysztof Kowalczyk Aneta Koroluk 《European journal of plant pathology / European Foundation for Plant Pathology》2014,139(1):9-12
Powdery mildew caused by Blumeria graminis DC. f. sp. avenae Em. Marchal. is a deleterious foliar disease of common oat which occurs in many parts of the world. Resistance existing in oat cultivars is broken down by new races of this pathogen and because of this fact there is necessity to look for new and effective sources of resistance to powdery mildew in oat. To identify new potential resistance sources to powdery mildew, a total of 67 oat genotypes from five different species Avena sterilis, A. fatua, A. sativa, A. maroccana and A. murphyi and 20 powdery mildew isolates were investigated for disease reactions. Among tested oat accessions the highest level of resistance was associated with A. maroccana genotypes. Genotypes belonging to species of A. murphi and A. sterilis also showed a good level of resistance. Identified genotypes could be used in oat breeding programmes to improve levels of resistance to powdery mildew. 相似文献
53.
Katarzyna Hura Tomasz Hura Renata Bączek-Kwinta Maciej Grzesiak Agnieszka Płażek 《Phytoparasitica》2014,42(2):145-154
The aim of this study was to find the biochemical markers of blackleg, evoked by the fungus Leptosphaeria maculans in seedlings of oilseed winter rape. Analyses of antioxidant enzymes activity and reactive oxygen species detection were performed 24, 48 and 72 h after inoculation. Moreover, measurements of the total pool of phenolic compounds, trans-cinnamic acid and ferulic acid were carried out. The results proved the virulence of Ph L5 isolate towards the rape seedlings. An increase in total phenolic content, including trans-cinnamic acid, was observed 24 h after inoculation. High activity of phenylalanine ammonia-lyase is probably another symptom of the defense mechanisms, despite the fact that it was not accompanied by elevated phenolics level, which were probably rapidly exhausted during Phoma lingam inoculation. A drop in phenolics content was balanced by higher activity of SOD, CAT and non-specific peroxidases. Enhanced activity of these enzymes was a response to the reactive oxygen species overproduction. ROS accumulation in indirectly inoculated first true leaves after inoculation may suggest a systemic defense response. 相似文献
54.
Hans Lutz Diane Addie Sándor Belák Corine Boucraut-Baralon Herman Egberink Tadeusz Frymus Tim Gruffydd-Jones Katrin Hartmann Margaret J. Hosie Albert Lloret Fulvio Marsilio Maria Grazia Pennisi Alan D. Radford Etienne Thiry Uwe Truyen Marian C. Horzinek 《Journal of Feline Medicine and Surgery》2009,11(7):565-574
OverviewFeline leukaemia virus (FeLV) is a retrovirus that may induce depression of the immune system, anaemia and/or lymphoma. Over the past 25 years, the prevalence of FeLV infection has decreased considerably, thanks both to reliable tests for the identification of viraemic carriers and to effective vaccines.InfectionTransmission between cats occurs mainly through friendly contacts, but also through biting. In large groups of non-vaccinated cats, around 30–40% will develop persistent viraemia, 30–40% show transient viraemia and 20–30% seroconvert. Young kittens are especially susceptible to FeLV infection.Disease signsThe most common signs of persistent FeLV viraemia are immune suppression, anaemia and lymphoma. Less common signs are immune-mediated disease, chronic enteritis, reproductive disorders and peripheral neuropathies. Most persistently viraemic cats die within 2–3 years.DiagnosisIn low-prevalence areas there may be a risk of false-positive results; a doubtful positive test result in a healthy cat should therefore be confirmed, preferably by PCR for provirus. Asymptomatic FeLV-positive cats should be retested.Disease managementSupportive therapy and good nursing care are required. Secondary infections should be treated promptly. Cats infected with FeLV should remain indoors. Vaccination against common pathogens should be maintained. Inactivated vaccines are recommended. The virus does not survive for long outside the host.Vaccination recommendationsAll cats with an uncertain FeLV status should be tested prior to vaccination. All healthy cats at potential risk of exposure should be vaccinated against FeLV. Kittens should be vaccinated at 8–9 weeks of age, with a second vaccination at 12 weeks, followed by a booster 1 year later. The ABCD suggests that, in cats older than 3–4 years of age, a booster every 2–3 years suffices, in view of the significantly lower susceptibility of older cats. 相似文献
55.
Tadeusz Frymus Diane Addie Sándor Belák Corine Boucraut-Baralon Herman Egberink Tim Gruffydd-Jones Katrin Hartmann Margaret J. Hosie Albert Lloret Hans Lutz Fulvio Marsilio Maria Grazia Pennisi Alan D. Radford Etienne Thiry Uwe Truyen Marian C. Horzinek 《Journal of Feline Medicine and Surgery》2009,11(7):585-593
OverviewRabies virus belongs to the genus Lyssavirus, together with European bat lyssaviruses 1 and 2. In clinical practice, rabies virus is easily inactivated by detergent-based disinfectants.InfectionRabid animals are the only source of infection. Virus is shed in the saliva some days before the onset of clinical signs and transmitted through a bite or a scratch to the skin or mucous membranes. The average incubation period in cats is 2 months, but may vary from 2 weeks to several months, or even years.Disease signsAny unexplained aggressive behaviour or sudden behavioural change in cats must be considered suspicious. Two disease manifestations have been identified in cats: the furious and the dumb form. Death occurs after a clinical course of 1–10 days.DiagnosisA definitive rabies diagnosis is obtained by post-mortem laboratory investigation. However, serological tests are used for post-vaccinal control, especially in the context of international movements.Disease managementPost-exposure vaccination of cats depends on the national public health regulations, and is forbidden in many countries.Vaccination recommendationsA single rabies vaccination induces a long-lasting immunity. Kittens should be vaccinated at 12–16 weeks of age to avoid interference from maternally derived antibodies and revaccinated 1 year later. Although some vaccines protect against virulent rabies virus challenge for 3 years or more, national or local legislation may call for annual boosters. 相似文献
56.
Helena Olczak-Woltman Małgorzata Schollenberger Wiesław Mądry Katarzyna Niemirowicz-Szczytt 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(3):385-393
Increased occurrence of cucumber angular leaf spot, Pseudomonas syringae pv. lachrymans, has caused significant losses in cucumber, Cucumis sativus, yield in Poland in recent years. These losses necessitated evaluation of the level of resistance in cucumber cultivars of
mainly Polish breeding, cultivated in Eastern Europe, and initiation of a breeding programme for resistance to this disease.
Screening for resistance was performed on 84 cucumber accessions under growth chamber conditions using a highly aggressive
strain of P. syringae pv. lachrymans. Most of the screened accessions were either susceptible or displayed intermediate resistance. The screening resulted in
the identification of five F1 hybrid cultivars moderately resistant to angular leaf spot. The identified F1 hybrids were self-pollinated up to the F4 generation. Individuals resistant to angular leaf spot were identified. These individuals can be used as a source of resistance
to angular leaf spot in future breeding efforts. 相似文献
57.
K. Köprücü 《Aquaculture Nutrition》2012,18(6):662-672
In the present study, it was examined whether variability in chemical composition of different cottonseed (Nazilli‐M39, Nazilli‐84 and Çukurova‐1518) meals (CSMs) and sunflower (Sanbro, Isera and Coban) meals (SFMs) had any effects on digestibility when fed to grass carp. Protein and energy digestibility of CSMs (83.2–86.8%; 88.7–92.5%) and SFMs (78.9–83.1%; 88.4–92%) had a coefficient of variation of 1.96% (CSMs) and 1.52% (SFMs) for protein and 1.93% (CSMs) and 1.82% (SFMs) for energy digestibility. Sum of amino acids digestibility of CSMs (83.1–86.5%) and SFMs (78.9–83.4%) had a coefficient of variation of 1.85% and 2.47%, respectively. Protein and energy digestibility of CSMs and SFMs was significantly positive affected by a range of compositional features including protein or sum of amino acids and phosphorus content, and significantly negative affected by fiber and carbohydrate contents in the test ingredients. This suggested that fiber and carbohydrate contents of CSMs and SFMs may also be influencing the nutritional value of its own protein or sum of amino acids. In conclusion, the relationship between plant protein meals protein content and its digestible value provides a good support for the development of a system of grain segregation by protein content and ingredient pricing according to that protein content. 相似文献
58.
In this study, the effects of less-expensive protein sources replaced with soybean meal on growth performance, nutrient utilization and body composition of juvenile grass carp were investigated. For this purpose, a control diet containing 42% soybean meal was prepared. Cotton seed meal (CSM), sunflower meal (SFM) and corn meal (CM) were added to the experimental diets by replacing 100% of the soybean meal protein used in the control diet. All diets were iso-nitrogenous (40% crude protein) and iso-caloric (19.5?MJ?kg?1 gross energy). Each treatment had three replicates, and 20 juvenile grass carps (3.5?±?0.1?g, initial weight) were located in per replicate. The fish were fed to satiety three times in a day during 3?months at 26°C of water temperature in glass aquarium (45 l). The results of the study showed that the weight gain (308.6?C448.6%), specific growth rate (1.56?C1.89%/day), feed conversion rate (1.2?C1.9), protein efficiency ratio (1.32?C2.08), and apparent digestibility coefficients of protein (80.5?C89%) or sum of amino acids (80.5?C88.9%) were not significantly affected by the experimental diets, except diet CM. All of these values obtained for the diet CM were significantly lower than those of fish fed on the control, CSM and SFM diets. However, there were no significant differences between the lipid digestibility of the diets, and crude protein, lipid, and gross energy contents in the whole body of fish in experiments. In conclusion, CSM and SFM diets were highly utilized by juvenile grass carp, but not CM diet. These results combined with the remarkable acceptability of diets containing high levels of plant protein ingredients with identical growth performances of juvenile grass carp show clearly that dietary soybean meal level can be considerably reduced without any adverse consequence in terms of somatic growth and nitrogen utilization. 相似文献
59.
Krzysztof Kupren Izabela Trąbska Daniel Żarski Sławomir Krejszeff Katarzyna Palińska-Żarska Dariusz Kucharczyk 《Aquaculture International》2014,22(1):29-39
This study analyzed the morphological development and allometric growth patterns of Lota lota L. (burbot) larvae reared under controlled laboratory conditions. From hatching to day 50, twenty larvae were sampled each [between 1 and 14 days post-hatch (DPH)] or every second day (between 14 and 50 DPH) and measured under a stereoscopic microscope using analytic software. Based on the external morphology, the different stages during early development of burbot were identified: yolk sac larva 0–8 DPH [3.92–4.37 mm total length (TL)]; preflexion larva 9–26 DPH (4.57–12.06 mm TL); flexion larva (between notochord degradation and its replacement with rays) 28–34 DPH (14.00–16.34 mm TL) and postflexion larva/juvenile 36–50 DPH (18.20–29.27 mm TL). Allometric growth patterns of some parameters (e.g., total length, head length, body length, tail length, head depth, body depth, eye diameter) were modeled by a power function and described by the growth coefficient. Organogenesis and changes of body proportions in burbot larvae were more rapid and complex during the yolk sac and preflexion phase of development as larvae developed most of their sensorial, feeding, respiratory and swimming systems and after notochord flexion, when most morphological changes were related to the progressive transformation from pelagic larva to demersal larva/juvenile. 相似文献
60.