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71.
Application of RAPD markers in the characterisation of Chrysanthemum varieties and the assessment of somaclonal variation 总被引:1,自引:0,他引:1
Characterisation of fifteen commercial varieties of Chrysanthemum was carried out through RAPD analysis. Varieties could be distinguished from each other and the level of similarity between
varieties seemed to be not very high. In vitro cultures were establish from four varieties and were subjected to different proliferation conditions. Five individuals from
each variety and treatment were analysed using RAPD at the beginning of the treatment and after a month of culture. Variation
was detected at both stages of the culture period. The rate of variation found showed differences between varieties, but no
significant difference was found between culture conditions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
72.
The standardized ASCE Penman–Monteith and FAO-56 equations were used to estimate reference evapotranspiration (ET0) using estimated and measured net radiation (Rn) and soil heat flux (G), based on hourly and daily meteorological data. The estimates were evaluated against lysimeter measurements. The results indicate that using measured or estimated values of Rn and G can have significant effect on the accuracy of the ET0 estimations, especially when calculations were made on an hourly basis. The FAO-56 version performed very well during the irrigation season on a daily basis. The use of measured Rn and G did not improve ET0 estimation on a daily basis, therefore, the use of estimated Rn and G appears to be dependable when calculations are based on 24-h weather data. When daily ET0 was calculated from hourly estimations, the results were different depending on the version used. The ASCE version was more accurate, especially when Rn and G were measured. Therefore, measurement of Rn and G may have potential to improve estimation only when daily ET0 is calculated from hourly estimations. The PM FAO-56 version was always a little less accurate than the ASCE version. For hourly calculations, using a constant surface resistance (as in FAO-56 version), the PM method underpredicted for high evaporative demand and vice versa. The ASCE version performed better than PM FAO-56 version when Rn and G were measured and estimated. Therefore, ASCE version tended to provide quite accurate values of hourly ET0, even using estimated values of Rn and G. As conclusion, the methods proposed by FAO-56 for estimating Rn and G tended to produce accurate estimates for daily and hourly ET0 under semiarid conditions and can be used with some degree of confidence for estimating ET0. In addition, results suggest that the ASCE standardized equation on an hourly basis improved the accuracy of ET0 estimation with respect to the FAO-56 version. 相似文献
73.
74.
Abias Santos Silva Luiz Gustavo Ribeiro Pereira Márcio dos Santos Pedreira Fernanda Samarini Machado Mariana Magalhães Campos Cristina Simões Cortinhas Tiago Sabella Acedo Rafael Dantas dos Santos João Paulo Pacheco Rodrigues Rogério Martins Maurício Thierry Ribeiro Tomich 《Journal of animal physiology and animal nutrition》2020,104(1):76-87
The effect of exogenous amylase on the in vitro rumen digestion kinetics of whole-crop maize silage made from dent (RB9004) or flint grain type (RB9308) was evaluated at different phenological stages: soft dough (SOD), early dent (EAD), ½ milkline (½M) and ¾ milkline (¾M). Forage was harvested from 70 to 110 days after sowing. Two rumen-cannulated cows receiving or not exogenous amylase (0.7 g/kg dry matter—DM, provided to achieve 396 kilo Novo units of amylase activity/kg of TMR DM) were used as donor of ruminal fluid. The in vitro gas production kinetics was evaluated according to a dual-pool logistic model. The chemical composition and gas production kinetics were affected by the hybrid and phenological stages. The flint hybrid had lower range for chemical analysis among physiological stages. Harvesting at ½M and ¾M improved DM content, bromatological composition and silage quality parameters compared to dent or flint types. Amylase (i) increased methane (CH4) production and in vitro dry matter digestibility (IVDMD) in ½M stage, (ii) improved digestion kinetics by reducing lag time and increasing total gas production and fermentation rates of non-fibrous carbohydrates (NFC) and fibrous carbohydrates (FC), and (iii) increased extent and fermentation rate of NFC and increased fermentation rate of FC fraction in whole-crop maize silages produced from dent or flint types in all phenological stages. Harvesting between ½M and ¾M is the best phenological stage to improve chemical composition and silage quality parameters. Exogenous amylase showed improvements on fibre digestion of silages at ½M and ¾M phenological stages in both grain types of corn. 相似文献
75.
76.
Gesto M Tintos A Alvarez R Soengas JL Míguez JM 《Fish physiology and biochemistry》2009,35(3):453-465
The contents of dopamine (DA), noradrenaline (NA), serotonin (5HT), and some related metabolites were studied in different
brain regions of rainbow trout at two different stages of sexual maturation (at the beginning of vitellogenesis), after naphthalene
(NAP) administration. The effects of NAP varied according to duration of exposure, brain region and vitellogenesis stage of
the trout, and were more significant during previtellogenesis. The changes observed in DA metabolism were generally stimulatory
after exposure for 3 h, and either stimulatory or inhibitory (depending on the brain regions) after exposure for 3 days to
NAP. NA levels were altered by NAP in various brain regions, but only during previtellogenesis. With respect to 5HT, treatment
with NAP reduced levels of the amine and/or its main metabolite in most of the brain regions studied, particularly 3 h after
treatment. The results suggest that NAP might interfere with the processes regulating brain monoamine metabolism, either locally
or indirectly by altering steroid feedback to brain centres, and thus disrupt endocrine control of reproductive development
through the brain–pituitary axis. 相似文献
77.
Luiz Henrique Agra Cavalcante-Silva Ana Carolina de Carvalho Correia José Maria Barbosa-Filho Bagnólia Araújo da Silva Bárbara Viviana de Oliveira Santos Daysianne Pereira de Lira Jéssica Celestino Ferreira Sousa George Emmanuel C. de Miranda Fabiana de Andrade Cavalcante Magna Suzana Alexandre-Moreira 《Marine drugs》2013,11(5):1553-1564
In this work, we investigated the spasmolytic effect of caulerpine, a bisindole alkaloid isolated from marine algae of the Caulerpa genus, on guinea pig ileum. Our findings indicated that caulerpine inhibited phasic contractions induced by carbachol (IC50 = 7.0 ± 1.9 × 10−5 M), histamine (IC50 = 1.3 ± 0.3 × 10−4 M) and serotonin (IC50 = 8.0 ± 1.4 × 10−5 M) in a non-selective manner. Furthermore, caulerpine concentration-dependently inhibited serotonin-induced cumulative contractions (pD′2 = 4.48 ± 0.08), shifting the curves to the right with Emax reduction and slope of 2.44 ± 0.21, suggesting a noncompetitive antagonism pseudo-irreversible. The alkaloid also relaxed the ileum pre-contracted by KCl (EC50 = 9.0 ± 0.9 × 10−5 M) and carbachol (EC50 = 4.6 ± 0.7 × 10−5 M) in a concentration-dependent manner. This effect was probably due to inhibition of Ca2+ influx through voltage-gated calcium channels (CaV), since caulerpine slightly inhibited the CaCl2-induced contractions in depolarizing medium without Ca2+, shifting the curves to the right and with Emax reduction. According to these results, the spasmolytic effect of caulerpine on guinea pig ileum seems to involve inhibition of Ca2+ influx through CaV. However, other mechanisms are not discarded. 相似文献
78.
Pablo Gómez-Ochoa Francisco Javier Miana-Mena María Jesús Mu?oz Encarna Cativiela Francisco Gómez 《Canadian journal of veterinary research》2005,69(4):309-312
The purpose of this study was to isolate and cultivate a subpopulation of pluripotent stem cells (PSCs) from the peripheral blood of rabbits, which are frequently used in veterinary research as an animal model. Pluripotent stem cells, as described in human beings, are fibroblast-like cells that exhibit a CD34 marker, specific from other hematopoietic stem cells. Commonly used human commercial media has been researched for culturing rabbit PSCs. These findings allow us to contemplate the direct application of this simple and standardized methodology in several areas of study, such as of the pharmacological effect of many drugs on hematopoietic cells, veterinary practice, and even the study of new strategies in cellular therapy for some human diseases. 相似文献
79.
80.
Twelve multiparous, cycling, lactating Holstein-Friesian cows were synchronised with prostaglandin F(2alpha) and treated with either 2.5 mg carazolol or saline. There were no differences between the peripheral blood concentrations of oestradiol or progesterone, but in the cows treated with carazolol the periovulatory surge of luteinising hormone was delayed, and oestrous behaviour was expressed later than in the control cows. 相似文献