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441.
Louis Butare Idupulapati Rao Philippe Lepoivre José Polania César Cajiao Juan Cuasquer Stephen Beebe 《Euphytica》2011,181(3):385-404
Bean species and genotypes show wide phenotypic variability in relation to aluminium (Al) resistance and progressive soil
drying. The objective of this study was to identify and characterize sources of resistance to Al toxicity and progressive
soil drying among six genotypes of common bean (Phaseolus vulgaris), four of runner bean (P. coccineus), and one of tepary bean (P. acutifolius), using hydroponic and soil cylinder screening methods. One experiment on hydroponic screening of Al resistance was carried
out using a basal nutrient solution with and without 20 μM Al. Two experiments were carried out using two oxisols in 80 cm
long soil cylinders with high Al (HAl) and low Al (LAl) saturation treatments. The three experiments showed an average of
36.9–53.5% inhibition of root growth with HAl compared with LAl treatments. Differences in root development and distribution
were observed among genotypes and species. Two accessions of P. coccineus (G35346-2Q, G35464-5Q) and one Andean common bean genotype (ICA Quimbaya) were outstanding in root and shoot growth in the
HAl treatments. P. coccineus accession (G35346-3Q) was outstanding under combined stress of Al-toxic acid soil and progressive soil drying. Accessions
of P. coccineus may represent unique sources of Al resistance for the improvement of common bean through interspecific crosses. 相似文献
442.
195 7年 ,西弗吉尼亚大学的 Dr.NormanOlson等人在研究滑液囊支原体的致病性时 ,从发病鸡的病变部位分离出了 1种对金属素、呋喃唑酮不敏感并能导致滑膜炎的病原体。 Olson在1 95 9报道 ,这种特别的病原体对链霉素也不敏感。Kerr等还发现这种病原体只对青年鸡致病 ,而这个日龄的鸡对支原体也很易感。随后 ,Olson和他的同事确认这种病原体是 1种病毒 ,他们称之为“病毒性关节炎病原”。由于它具有双股核酸 ,所以第 1次被误诊为痘病毒。随后这种病毒被Walker等人通过电镜观察定名为呼肠孤病毒。给鸡试验感染这种呼肠孤病毒后 ,能引发关节炎… 相似文献
443.
Christopher J Dutton Randall E Junge Edward E Louis 《Journal of zoo and wildlife medicine》2003,34(1):16-24
Complete health assessments were performed on 20 adult ring-tailed lemurs (Lemur catta), 10 males and 10 females, free ranging within the Tsimanampetsotsa Strict Nature Reserve in southwest Madagascar. Each animal was anesthetized using tiletamine and zolazepam, weighed, and given a thorough physical examination. Blood was collected for hematology, determination of plasma total protein concentration, serum chemistry, determination of fat-soluble vitamin and trace mineral concentrations, assessment of iron metabolism, toxoplasmosis and viral serologies, and examination for parasites. Feces were collected for bacterial culture and parasite examination, and representative numbers of ectoparasites were collected. Blood values differed significantly in a number of ways from values in captive lemurs, possibly associated with recent food consumption, hydration, and diet. There was no evidence of serious infectious disease and no hemoparasites. The enteric flora appeared unremarkable, although results may have been skewed toward cold-tolerant bacteria. The fecal parasite burden was low, but there were large numbers of ectoparasites (mites) present. Our study demonstrated that a substantial amount of data can be collected from free-ranging populations, information that is invaluable in the management of captive populations, particularly with regard to disease, and in assessing risks associated with reintroduction programs. 相似文献
444.
Louis R. D'Abramo Cortney L. Ohs Terrill R. Hanson 《Journal of the World Aquaculture Society》2004,35(1):33-45
Sunshine bass from Phase I or pond production were graded into two weight classes, 3 and 5 g, and stocked into experimental earthen ponds at a density of either 8,649/ha or 11,120/ ha in a 2 × 2 factorial design. After stocking, the fish were fed a commercially manufactured feed (43.0-45.5% crude protein) twice daily to satiation for 17 mo. At harvest, mean survival ranged from 67.4 to 84.8% but was highest for the fish stocked at 5g. Average production Tor ponds stocked at 8,649/ha and 11,120/ha, regardless of stocking weight, was 4,506 kg/ha and 5350 kg/ha, respectively. Production and percentages of assigned weight classes were not significantly different among treatments as a result of wide variation among replicates. Using size-dependent market prices assigned to the different harvest size groups, an economic analysis revealed gross receipts, variable costs, and total costs for the 11,120/ha 5-g treatment. Net returns were not significantly different among the four treatments due to large variation among replicates per treatment. These results confirm that the traditional phase II of pond production can be eliminated in favor of a direct stocking of phase I fish into a single production phase and economically competes very well with traditional three-phase growout management. The potential reduction in turnover time of production units achieved through the direct stock practice is an efficiency trait that should translate into significantly higher returns and a greater profit over the long term. Further reduction of stocking density combined with a stocking weight greater than 5 g should translate into greater proportion of larger, higher valued fish at harvest and a growout period of 18-20 mo, rather than the 24-30 mo traditionally needed for the combined phase II and phase III of production. 相似文献
445.
When containerized black spruce seedlings (Picea mariana (Mill.) B.S.P.) are grown rapidly in greenhouse culture, they sometimes bend over, grow horizontally and become deformed. This phenomenon has been known to affect between 5% and 10% of a winter greenhouse crop. In this study, near-ultraviolet lamps were used to supplement the artificial light received from high-pressure sodium lamps and the effects on seedling morphology and lignin contents were examined. Neither height to diameter ratios nor lignin concentrations were significantly affected by UV radiation flux density. However, seedling biomass, height, root collar diameter, lignin content, and lignin to cellulose ratios of stems were significantly correlated with total photosynthetic photon flux density (PPFD) received during photoperiod extension. Height to diameter ratios were negatively correlated with PPFD during photoperiod enhancement because of a greater relative increase in diameter growth compared with height growth. Neither UV nor PAR flux density affected the percentage of black spruce seedlings having stem deformations greater than 30 ° from the vertical.
Résumé Lorsque des semis d'épinette noire (Picea mariana (Mill.) B.S.P.) en conteneur sont forcés d'avoir une croissance rapide en serre, leur tige est parfois courbée ou déformée. Ce phénomène peut affecter entre 5% et 10% d'une culture serricole hivernale. Dans la présente étude, un enrichissement du rayonnement près de l'ultraviolet a été appliqué sur des semis en complément à l'éclairage artificiel procuré par des lampes au sodium à haute pression. La morphologie et le contenu en lignine des semis ont alors été examinés. Le rapport entre la hauteur et le diamètre des semis, et la concentration en lignine n'ont pas été significativement affectés par la densité du flux photonique ultraviolet. Cependant, la biomasse, la hauteur, le diamètre au collet, le contenu en lignine et le ratio lignine: cellulose des tiges des semis ont été significativement corrélés à la densité du flux photonique photosynthétique (PPFD) reçue pendant l'extension de la photopriode. Le rapport entre la hauteur et le diamètre a été négativement corrélé à la PPFD pendant l'augmentation de la photopériode à cause de la plus grande croissance en diamètre des semis comparativement à leur croissance en hauteur. La densité du flux photonique au niveau de l'ultraviolet comme au niveau de la radiation photosynthétiquement active n'a pas affecté le pourcentage de semis d'épinette noire ayant des déformations de leur tige plus grande que 30 ° comparativement à la verticale.相似文献
446.
Dunié-Mérigot A Huneault L Parent J 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(1):63-68
The clinical aspects of 26 dogs suspected of fibrocartilaginous embolic myelopathy (FEM) were documented and compared to results from 2 studies published in the literature. The short-term recovery capacity of 15 of these patients was also evaluated during a 30 day period by giving a neurological score. We have observed, compared to other studies, a larger proportion of cervical localization (15.4%) as well as a larger variety of race sizes for FEM. We have established that, after 30 days, 67% of patients had improved and that 88% of non-ambulatory patients had regained their ambulatory capacity. Also, patients showing signs of grey matter lesions (inferior motor neuron--IMN) as well as those having white matter lesions (superior motor neuron--SMN) had shown signs of neurological progress. Therefore, we have observed that the recovery capacity of an animal suffering from FEM does not seem to be impacted by its initial ambulatory state, nor by its lesions to IMN or SMN, although the low number of cases does not allow us to positively confirm this situation. 相似文献
447.
The reviewed literature supports full crown restoration in all endodontically treated teeth other than incisors in humans [corrected] In general terms, a crown is a cemented, extra-coronal restoration that covers the entire outer surface of the clinical crown. Prosthodontic treatment, and particularly crown restoration in veterinary patients has been the subject of general informational articles and veterinary dental texts. These publications have discussed techniques for crown preparation, fabrication, and cementation as well as the general principles of prosthodontic treatment. The purpose of this review is to present available information on this topic in an organized manner which will help veterinary dentists to use an evidence-based approach when deciding on a type of final restoration for their endodontic patients. 相似文献
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