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101.
Jean Guyot Virgile Condina Fabien Doaré Christian Cilas Ivan Sache 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(3):349-362
South American leaf blight (SALB) is a severe threat to world rubber production. One way of controlling it is to set up plantations
in zones not conducive to the disease. Such zones are known once a plantation has been set up, but few data are available
on how climate affects the disease, especially in the Amazon region. With better knowledge of conditions that are favourable
to SALB epidemics it would be possible to more accurately identify risk zones in Asia and Africa, continents that are still
SALB-free. Based on a trial design involving detailed and frequent observations, and with a method rarely used in plant epidemiology,
the segmentation method, the results presented in this article make it possible to list, in order of importance, climatic
factors that influence disease severity under conditions where the climate varies little over the year. 相似文献
102.
Maćerak Anita Leovac Ivančev-Tumbas Ivana Börnick Hilmar Ilić Gordana Isakovski Marijana Kragulj Maletić Snežana 《Journal of Soils and Sediments》2019,19(2):964-972
Journal of Soils and Sediments - This study utilizes column tests to investigate the retardation of certain herbicides with different hydrophobicities (atrazine, alachlor and trifluralin) during... 相似文献
103.
104.
In addition to Hymenoscyphus fraxineus, two fungi identified as Diaporthe eres aff. and Fusarium sambucinum aff. were also isolated from necrotic bark lesions on declining one‐year‐old Fraxinus excelsior in a forest stand in Montenegro. To examine their involvement in ash decline, a pathogenicity test was performed using under bark inoculations on one‐year‐old Fraxinus excelsior. Hymenoscyphus fraxineus was included as comparison. All three fungal species proved highly pathogenic towards one‐year‐old seedlings although lesion sizes differed significantly between the different species. Hymenoscyphus fraxineus was most aggressive, followed by F. sambucinum aff., while D. eres aff. caused the smallest lesions. This study demonstrates for the first time the ability of isolates in the D. eres and F. sambucinum species complexes to cause decline on one‐year‐old common ash seedlings. 相似文献
105.
A procedure for the production of conjugates of soybean peroxidase (SbP) oxidized by sodium periodate and anti-mouse IgG antibody (Ab) was optimized. A sandwich chemiluminescent enzyme-linked immunosorbent assay (ELISA) for determination of mouse IgG using SbP and specific Ab was developed, and SbP-catalyzed oxidation of luminol was carried out in the absence of any enhancer. Comparison of conjugates produced by labeling Ab by soybean and horseradish peroxidases in the chemiluminescent ELISA showed that in the case of SbP a rate of emission decay formed through luminol oxidation was significantly lower. Application of the soya enzyme allowed the development of the immunoassay with improved sensitivity and a wider linear range. 相似文献
106.
George M. Strain MS PhD Michael T. Kearney MS Ivan J. Gignac Donald C. Levesque DVM Holly J. Nelson DVM Bruce L. Tedford MA Laura G. Remsen MS DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1992,6(3):175-182
To screen for congenital deafness, brainstem auditory-evoked potential (BAEP) testing was performed on 1031 Dalmatians from three geographically separated areas. Phenotypic marker assessment was done to determine markers possibly associated with deafness. Markers included sex, hair coat color, pigmentation of different areas of skin (eye rims, nose, and ears), presence of a patch, spot size and marking (density of spotting), sire and dam BAEP status, and presence of iris and retinal tapetal pigmentation. Combined data from all test sites showed 8.1% bilateral deafness (N = 83 dogs) and 21.6% unilateral deafness (N = 223), or an overall 29.7% incidence of hearing disorders. Significant (P less than 0.05) associations with deafness for the data from all test sites combined were seen for patch, sire and dam BAEP, iris pigment, and retinal pigment. However, results differed for several of the significant phenotypic markers when analyses were done on the data from the individual test sites; changes from significant to not significant were found. This suggested the existence of multiple populations of deafness patterns, and reinforced the precautionary conclusion that associations of phenotypic markers with deafness are not necessarily functionally significant. 相似文献
107.
M Hidiroglou M Ivan J G Proulx M J Davicco V Coxam J P Barlet 《Research in veterinary science》1992,53(1):32-37
An investigation was undertaken to ascertain the possibility of a relationship between calcium, inorganic phosphorus, magnesium, 1,25-dihydroxyvitamin D [1,25(OH)2D], and insulin-like growth factor-1 (IGF-1) concentrations in blood plasma and occurrence of congenital joint laxity and dwarfism (CJLD) in young cattle. Pregnant cows were fed hay (30 cows) or grass silage (122 cows) during winter months (October 15 to calving in March). Blood samples were taken from cows on seven occasions during the experiment and 48 hours after calving, and from calves at birth, and at seven, 14 and 56 days old. Five per cent of calves born (six of 122) to cows fed grass silage and none born to cows fed hay were affected by CJLD. The diet and health status of calves were not significantly (P greater than 0.05) associated with the plasma concentration of 1,25(OH)2D. The plasma calcium concentration declined with age of the calves (P less than 0.05) but was not affected by the occurrence of CJLD. Plasma phosphorus and magnesium concentrations in calves born to cows fed silage were higher (P less than 0.05) than in those born to cows fed hay. At birth and seven days old, plasma phosphorus concentrations were higher (P less than 0.05) in CJLD-affected calves than in healthy calves but the plasma concentration of IGF-1 was not different (P greater than 0.05). It was concluded that the high plasma phosphorus concentrations in CJLD-affected calves and their dams could be related to the aetiology of the CJLD condition in calves. 相似文献
108.
Effects of faunation and type of dietary protein on gastric solubility and liver content of copper in sheep 总被引:1,自引:0,他引:1
M Ivan 《Journal of animal science》1989,67(11):3028-3035
Three experiments were conducted to determine the influence of the presence of protozoa on copper (Cu) metabolism in sheep fed corn silage or corn silage supplemented with casein, fish meal or soybean meal. For each diet, eight rams were kept fauna-free; eight additional rams were faunated and housed separately from them. The faunated rams in all treatments grew faster and consumed more feed and, consequently, more Cu. However, they had a lower (P less than .01) ruminal Cu solubility and accumulated less Cu in their livers than the fauna-free rams when fed corn silage alone or in combination with soybean meal (insoluble, ruminally degraded protein). Such effects were not significant when corn silage was supplemented with fish meal (protein resistant to ruminal degradation). The presence of ciliate protozoa in the rumen had no effect on the accumulation of Cu in the liver of sheep fed corn silage supplemented with casein (soluble, ruminally degraded protein) and produced conflicting results on ruminal Cu solubility. Hence, the effect of protozoa on Cu metabolism is indirect and depends on the type of protein present in the diet. 相似文献
109.
Spugnini EP Citro G Dotsinsky I Mudrov N Mellone P Baldi A 《Veterinary journal (London, England : 1997)》2008,178(2):291-293
An 8-year-old male castrated cat was referred for sudden onset of lameness. Physical examination revealed a 1x2x1cm mass originating from a footpad of the right hind leg. A diagnosis of ganglioneuroblastoma was suggested by the tumour appearance following histopathological staining with haematoxylin and eosin and haematoxylin/van Gieson. Immunohistochemical staining for glial fibrillary acidic protein (GFAP), vimentin, neuron-specific enolase (NSE), neurofilament and S100 further confirmed the diagnosis. The staging process did not indicate metastatic spread. The cat was treated with three sessions of electrochemotherapy (ECT) 1 week apart, following local injection of bleomycin. The tumour had completely regressed within 1 week of the third ECT application and remained in remission for 402 days at which time a small recurrence was noted. The animal was given a further session of ECT using intra-lesional cisplatin and again went into remission. It remained tumour free at 450 days. Electrochemotherapy is considered a safe and effective treatment for localised neoplasms of cats and dogs and warrants further investigation. 相似文献
110.
Objective The Leatherback sea turtle is the largest extant reptile and the sole member of the family Dermochelyidae. Here, the eye of this critically endangered marine turtle was investigated to determine the anatomy, optics, and optical sensitivity. Animals studied Three Leatherback sea turtles, Dermochelys coriacea. Results The eye is small in proportion to body size of the adult compared to other vertebrates, with prominence of the retractor bulbi and pyramidalis muscles. The nictitans shows extensive folding of the bulbar conjunctiva as an apparent mechanism to increase the surface area for mucus secretion. The intraocular anatomy is consistent with an eye adapted to aquatic vision with minimal curvature of the cornea, a near‐spherical lens, deep ciliary cleft and highly vascularized ciliary body. The optical sensitivity, a measure of the sensitivity to light of a given optical system, is higher than in other marine turtles studied but lower than those found in teleost fish that share a habitat with the Leatherback sea turtle. Conclusions The Leatherback sea turtle shows ocular features that are characteristic of Chelonians with similarities to aquatic mammals. The calculated optical sensitivity suggests that compared to pelagic fishes, for instance, the Leatherback sea turtle eye is not particularly well adapted for vision in dim light even though this species is known to venture into deep, dark waters, and might feed at night. 相似文献