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In vitro culture of shoot-tips of rhubarb (Rheum rhaponticum L.) on the medium of Murashige and Skoog (1962), containing 1 mg/l of 6 benzylaminopurine and 1 mg/l of 3-indolebutyric acid, induced the development of axillary buds. Rooting was easily attained in 4–5 days by omitting the cytokinin from the basal medium. The temperature was 25 ± 1° C during the 16-h photoperiod and 20 ± 1° C during the 8-h dark period. The rooted plantlets were transplanted to soil medium with 70% success. The method described gives a multiplication rate of 5 per month. 相似文献
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A new fipronil-based spot-on formulation was evaluated against experimental flea infestations in cats in two studies. In both studies, eight cats served as negative controls (groups 1 and 4); on day 0, eight cats were treated with a 10% w/v fipronil-based spot-on solution (Effipro Spot-on, 0.5ml per cat, groups 2 and 5) and eight cats served as positive controls (Frontline Spot-on, 0.5ml per cat, groups 3 and 6). Each cat was infested on day - 1 with 50 fleas (study 1) and weekly (day 7-day 56) with 100 fleas (study 2). Geometric mean flea counts obtained 48h after the treatment or each re-infestation were reduced by 99.0 and 98.3% in groups 2 and 3, respectively, on day 2, compared to the negative control group. Cats were protected from re-infestations with an efficacy >99% for 58 days in group 5 and for 37 days in group 6. 相似文献
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Cadiergues MC Laguerre C Roques M Franc M 《American journal of veterinary research》2004,65(2):151-154
OBJECTIVE: To evaluate efficacy of 2 deltamethrin emulsifiable concentrates that differed on the basis of vehicle (methyl glycol acetate [AMG] or 2-propylene glycol 1-methyl ether acetate [AMP]) for the treatment of sheep with mange. ANIMALS: 30 ewes between 11 months and 7 years old that weighed 16 to 71 kg and were naturally infested with Psoroptes ovis. PROCEDURE: Sheep were randomly allocated into 3 groups (13 sheep in group AMP, 13 sheep in group AMG, and 4 negative-control sheep). Each sheep was dipped twice (10-day interval between dippings) in the assigned formulation. Assessment of efficacy was performed on days 3, 7, 14, 21, 28, 35, 42, 49, 56, and 63 after the first dipping. Efficacy was assessed by determining the number of eggs or live mites on those days, as well as regrowth of wool at the end of the study. RESULTS: Psoroptic mange infestation was maintained in the 4 control sheep throughout the study. We did not detect live Psoroptes mites in scrapings after day 7 (AMP group) or after day 14 (AMG group). No parasites were seen after day 14 in either treatment group. Therefore, efficacy was 100% for both treatment groups from days 14 to 63. CONCLUSIONS AND CLINICAL RELEVANCE: The 2 formulations of deltamethrin were equally able to eradicate Psoroptes infestation of sheep after 2 dippings performed in accordance with the label recommendations. 相似文献
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Vesper HW Slimani N Hallmans G Tjønneland A Agudo A Benetou V Bingham S Boeing H Boutron-Ruault MC Bueno-de-Mesquita HB Chirlaque D Clavel-Chapelon F Crowe F Drogan D Ferrari P Johansson I Kaaks R Linseisen J Lund E Manjer J Mattiello A Palli D Peeters PH Rinaldi S Skeie G Trichopoulou A Vineis P Wirfält E Overvad K Strömberg U 《Journal of agricultural and food chemistry》2008,56(15):6046-6053
Acrylamide exposure was investigated in subgroups of the EPIC study population (510 subjects from 9 European countries, randomly selected and stratified by age, gender, and smoking status) using hemoglobin adducts of acrylamide (HbAA) and its primary metabolite glycidamide (HbGA). Blood samples were analyzed for HbAA and HbGA by HPLC/MS/MS. Statistical models for HbAA and HbGA were developed including body mass index (BMI), educational level, and physical activity. A large variability in acrylamide exposure and metabolism between individuals and country groups was observed with HbAA and HbGA values ranging between 15-623 and 8-377 pmol/g of Hb, respectively. Both adducts differed significantly by country, sex, and smoking status. HbGA values were significantly lower in high alcohol consumers than in moderate consumers. With increasing BMI, HbGA in nonsmokers and HbAA in smokers decreased significantly. In the assessment of potential health effects related to acrylamide exposure, country of origin, BMI, alcohol consumption, sex, and smoking status should be considered. 相似文献
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To obtain crossing products, an efficient pollination and subsequent fertilization is essential. This efficient pollination is achieved by pollen germination and tube growth. Here, these pollen characteristics of 2 genetically differentiating cultivars of Anemone coronaria L. were investigated in vitro. For the essential components boron, calcium and an osmoticant, only calcium showed to be crucial for pollen germination. Boron concentrations influenced the pollen tube length with a concentration of 100 mg l?1 H3BO3 resulting in the longest pollen tubes. For the osmoticant sucrose, a concentration of 100 g l?1 caused a significant positive effect on both pollen germination and pollen tube length for the 2 cultivars. The cultivars reacted similarly with respect to the investigated compounds. Next to this, the pollen development was correlated with 8 different flower stages in A. coronaria. As a final point, the germination of an optimized pollen germination medium was compared with in vivo pollen germination in cross-pollinations within the same cultivar (identified by aniline blue staining). For ‘Mistral Wine’, pollen germination percentage was lower in vitro than in vivo, while ‘Wicabri Blue’ pollen showed no significant difference in germination rates in vivo and in vitro. To achieve fertilization a following requisite is that the stigma is receptive. To study this, the most receptive female flower stage of the 8 different flower stages for A. coronaria was characterized by aniline blue staining. A. coronaria clearly showed protogyny. 相似文献
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Helleborus species are members of the family of the Ranunculaceae. These popular perennials are all diploids (2n = 2x = 32). This study investigates polyploidy induction by different antimitotic agents. Colchicine, oryzalin and trifluralin
were tested in vitro on shoots of Helleborus niger, H. orientalis and H. × nigercors. Furthermore the effect of the antimitotic agents on the viability and the multiplication rate of cultured plantlets were
analyzed. Flow cytometry demonstrated that polyploidisation was genotype dependent: using H. niger, tetraploids were obtained using either oryzalin (3 μM) or trifluralin (3 or 10 μM), whereas for H. × nigercors only trifluralin (3 or 10 μM) induced polyploidisation. For H. orientalis neither treatment was effective to produce tetraploids or mixoploids. For these three species, colchicine (100 μM) was ineffective.
The polyploidisation events in H. niger and H. × nigercors were confirmed by chromosome counts of mounted nuclei derived from root tips (2n = 4x = 64). 相似文献
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Karel Folens Marie-Christine Van Labeke Gijs Du Laing 《Water, air, and soil pollution》2017,228(12):457
Urban horticulture is gaining more and more attention in the context of sustainable food supply. Yet, cities are exposed to (former) industrial activities and traffic, responsible for emission of contaminants. Trace elements were monitored in soils located in the urban environment of Ghent (Belgium) and 84 samples of Lactuca satica L. lettuce grown on it. The effects of cultivation in soil versus trays, neighbouring traffic and washing of the lettuce before consumption were studied. The 0–30 cm top layer of soils appeared heterogenic in composition and enriched in Co, Cd, Ni and Pb within 10 m from the nearest road. Yet, no similar elevated concentrations could be found in the crops, except for As. Besides uptake from the roots, the presence of trace elements in the plants is also caused by the atmospheric deposition of airborne particulate matter on the leaf surface. Correlation analysis and principal component analysis (PCA) revealed that this latter transport pathway might particularly be the case for Pt, Pd and Rh. Concentrations of Cd did not exceed the 0.2 mg kg?1 (fresh weight) threshold for Cd in leafy vegetables set by the European Commission. Measurements to reduce the health risks include the washing of lettuce, which effectively reduced the number of samples trespassing the maximum Pb level of 0.3 mg kg?1 (fresh weight). Also, cultivation in trays resulted in a lower As content in the plants. Taking into account a vigilance on crop selection, cultivation substrate and proper washing before consumption are considered essential steps for safe domestic horticulture in urban environments. 相似文献
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Jackie Tapprest DVM Fabrice Audigie DVM PHD Catherine Radier DM Marie-Christine Anglade DM Marie-Catherine Voisin DM PHD Nathalie Foucher Claire Collobert-Laugier DVM Didier Mathieu DM PHD Jean-marie Denoix DVM PHD 《Veterinary radiology & ultrasound》2003,44(4):438-442
In humans, magnetic resonance (MR) imaging is the method of choice for the diagnosis of stress fractures. In this paper, bilateral stress fracture of the lateral condyle of the third metacarpal bone in a French trotter is described. Results of the radiographic, MR imaging, and histologic examinations are presented, with a focus on the MR signal abnormalities found. Based on this patient, the potential use of MR imaging for the diagnosis of stress fractures in horses is discussed. 相似文献
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Luca Pipino Marie-Christine Van Labeke Andrea Mansuino Valentina Scariot Annalisa Giovannini Leen Leus 《Euphytica》2011,178(2):203-214
Fertility of hybrid tea roses is often reduced due to their interspecific origin but also to intensive inbreeding. New genotypes
used as pollen donors represent an economic risk for a breeding programme, as their influence on seed production is unknown.
In this study 11 cut rose genotypes were selected from a company database as high fertile or low fertile male parents, according
to the number of seeds per hybridisation. Pollen morphology and in vitro germination of the selected genotypes were characterised.
Pollen was either small (mean diameter <30 μm), shrunken, and irregular (abnormal), or large (mean diameter >30 μm), elliptical
and crossed by furrows (normal). High correlations were found between the number of seeds produced per hybridisation and the
pollen diameter (r = 0.94) or the percentage of normal pollen (r = 0.96). In order to evaluate the predictive power of the models, we conducted regression analyses and performed a validation
experiment on genotypes not present in the database and without background information on fertility. Pollen diameter and percentage
of normal pollen were characterised and fitted in the regression models for seed set predictions. Validation with an independent
dataset gave a good prediction for 83.3% of the data. This indicates that using either the mean pollen diameter or the percentage
of normal pollen resulted in effective fertility prediction. This tool could enhance the genetic variability in crossings
between hybrid tea roses, thus creating possibilities for less economically risky exploitation of new tetraploid genotypes
as male parents. 相似文献