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12.
del Río ML Gutiérrez B Gutiérrez CB Monter JL Rodríguez Ferri EF 《American journal of veterinary research》2003,64(9):1176-1180
OBJECTIVE: To determine duration and rates of recovery of Actinobacillus pleuropneumoniae and Haemophilus parasuis from 4 liquid media and 2 swab specimen transport systems and compare findings with those of Escherichia coli. SAMPLE POPULATION: One strain each of A pleuropneumoniae (biovar 1, serotype 1), H parasuis (serovar 5), and E coli (serotype O149:K91:H19). PROCEDURE: Strains were incubated in brain heart infusion broth supplemented with horse serum and other nutrients or in horse serum alone, with and without nicotinamide-adenine dinucleotide in both instances, for 150 days at 4 degrees C or room temperature (21 degrees C). Similarly, strains were tested in Stuart and Amies transport systems after storage at room temperature for 8 days. RESULTS: Colony counts greater than those of the initial inoculum were observed after incubation in horse serum for A pleuropneumoniae but not for H parasuis. Overall, incubation at 4 degrees C in the 4 liquid media resulted in longer recovery duration and higher rates than at room temperature. Culture of H parasuis resulted in lower recovery rates and shorter durations of recovery than culture of A pleuropneumoniae, except for culture in horse serum. Haemophilus parasuis survived longer than A pleuropneumoniae in the transport systems, and all organisms survived longer in the Amies system. CONCLUSIONS AND CLINICAL RELEVANCE: Survival of A pleuropneumoniae and H parasuis indicated that horse serum prolongs survivability, which may result in exposure of more animals during a prolonged period. The Amies system might be a good choice for collection of clinical samples from animals, especially for recovery of H parasuis. 相似文献
13.
Intracavitary Cisplatin Chemotherapy Experience with Six Dogs 总被引:1,自引:0,他引:1
Antony S. Moore MVSc Claudia Kirk DVM Aglaia Cardona DVM 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1991,5(4):227-231
Six dogs with a median age of 7 years (range = 5-14 years) were presented for signs referable to thoracic or abdominal effusion associated with neoplasia of the body cavities. Intracavitary cisplatin was administered at 50 mg/m2 every 4 weeks for a median of 2.5 treatments (mean = 3, range = 1-6). Three dogs with pleural mesothelioma had complete resolution of effusion for 289, 129, and greater than 306 days without evidence of tumor growth. Resolution of effusion occurred after one treatment in two dogs and after two treatments in one dog. In three dogs with carcinomatosis of unknown origin, complete responses was seen in two dogs after one treatment for 255 and greater than 807 days, respectively. Intracavitary chemotherapy with cisplatin was associated with palliation and control of malignant pleural and/or abdominal effusion in five of six dogs. Toxicity was minimal, and this method of therapy should be further explored in dogs with similar malignancies. 相似文献
14.
Wilson Wagner Ribeiro Teixeira Rafael Battisti Paulo Cesar Sentelhas Milton Ferreira de Moraes Adilson de Oliveira Junior 《Journal of Agronomy and Crop Science》2019,205(5):533-544
Soya bean yield gap can be caused by different factors resulting in uncertainties when the objective is to use such information for farm decision‐making and reference yield determination. Thus, this study aimed to quantify the soya bean yield gap for four sites, located in Southern and Midwestern Brazil, as well as the uncertainties of that related to cultivars, sowing dates, soil types and reference yields. The crop simulation model DSSAT‐CSM‐CROPGRO‐Soybean was calibrated for cultivars with similar maturity groups, based on the data obtained from the best farmers at the county level. The yield gap by water deficit (YGWD) was obtained through the difference between potential and attainable yields, and that one caused by sub‐optimum crop management (YGCM) by subtracting actual yield of each county, obtained from official statistics between 1989/90 and 2014/15 growing seasons, from the estimated attainable yield. The yield was simulated using four sowing dates, three soil types and two soya bean maturity groups by county. The reference yield uncertainty was quantified using yield reference from crop model and regional winners of the soya bean yield context, conducted by CESB (Brazilian Soybean Strategic Committee), for the growing seasons from 2013/14 to 2015/16. The crop model showed a good agreement between measured and simulated crop development and growth using calibration by maturity group, with low root mean square error (347 kg/ha). Southern sites had a mean YGWD of 1,047 kg/ha, while in the Midwest, it was lower than 100 kg/ha. The YGCM was 1,067, 528, 984 and 848 kg/ha, respectively, for Castro, PR, Mamborê, PR, Montividiu, GO and Primavera do Leste, MT, representing the opportunity for yield gain when having the best farmers as reference. The maturity groups, sowing dates and soil types showed to be an important source of uncertainty for yield gap determination, being recommended to investigate the farms in detail for an appropriate quantification. The reference yield showed expressive uncertainties, with some farmers presenting conditions to increase their soya bean yields by more than 3,000 kg/ha, when considering as reference the yields obtained by the winners’ farmers. These results show that uncertainties must be reduced when assessing farm yield gaps, in order to ensure that expected rate of soya bean yield growth could be reached by adopting the same technologies from CESB winners and best farmers in the county as a reference. 相似文献
15.
温度对大叶桃花心木(Swietenia macrophylla King)幼苗叶片的光合影响 总被引:2,自引:0,他引:2
本文研究了大叶桃花心木(Swietenia macrophylla King)一年生幼苗在经过夜温处理后的光响应曲线和在饱和光强下的CO2反应曲线.结果表明:在大气CO2浓度下,叶片的最佳光合作用温度在25-31℃之间,而在饱和CO2浓度下为31-35℃.在25℃以下光合速率开始降低,主要是由于羧化效率的降低,而当温度超过31℃时,光合速率下降,是因为羧化效率的降低和呼吸速率的增加.CO2浓度对光合的促进作用在低温下受到抑制,这意味着未来在CO2浓度增高的情况下,高浓度的CO2对热带常绿植物光合的促进在冬天低温情况下表现不十分明显.图4参23. 相似文献
16.
Lima Pedro Paulo Arcanjo Narciso Luis Gustavo Alcindo Jefferson Filgueira Deschk Maurício Ciarlini Paulo Cesar dos Santos Paulo Sérgio Patto de Almeida Breno Fernando Martins 《Veterinary research communications》2022,46(1):27-35
Veterinary Research Communications - Propofol is a widely used drug in veterinary medicine to induce anesthesia; as well as the chosen compound for protocols of intravenous anesthesia. The present... 相似文献
17.
Jose Renato de Oliveira Cesar Spencer Malecha Jinzeng Yang 《Aquaculture (Amsterdam, Netherlands)》2006,261(2):688-694
Morphological changes and biochemical composition of abdominal muscles over the molt cycle were investigated in juvenile Litopenaeus vannamei. Eight molt stages were characterized and clear uropod images are presented. Molt frequency was highly correlated with the age of the shrimp. Juvenile shrimps appeared to molt faster at one month of age (4.6 ± 0.5 days/cycle), slow to 11.8 ± 1.7 days/cycle at three months of age, and reach a long molt cycle at six months (17.2 ± 2.7 days/cycle). Myofiber cross-sectional images revealed specific morphological changes in abdominal muscle associated with each molt stage. Expanded fiber size was observed during intermolt stages. Water content and total soluble proteins were balanced throughout the molt cycle. Total DNA concentration increased in intermolt and premolt, while total RNA concentration remained stable except in late-premolt stages. SDS-PAGE analysis showed high levels of actin and myosin in postmolt, reaching a plateau in intermolt and declining in premolt. These results suggest the occurrence of muscle fiber rearrangement in both the premolt and postmolt stages. Abdominal muscle buildup occurs mostly during the intermolt stage. 相似文献
18.
Cesar Ricardo Arruda Fernanda Ramiro Vanessa Faria Roberto Barcelos Daniel Pontes Fernanda Passos Fabiano Kaiser Karoline dos Santos Teixeira Aline Maria Serrano Aline Abreu Leticia Siqueira Danielle Teixeira Matheus Vezzone Mariana Polivanov Helena Castilhos Zuleica 《Journal of Soils and Sediments》2022,22(2):547-558
Journal of Soils and Sediments - This study consists of the evaluation of metals acute toxicity levels taking into consideration a hypothetic scenario of dam breaking and land deposition of two... 相似文献
19.
Flávio Martins Santana Cesar Bauer Gomes Cesar Rombaldi Valmor João Bianchi Ailton Reis 《Phytoparasitica》2013,41(5):557-568
The populations of Phytophthora infestans (Pi) in southern Brazil in 2004 and 2005 are characterized herein. The isolates were collected from potato and tomato plants in the states of Paraná (PR), Santa Catarina (SC), and Rio Grande do Sul (RS). The mating type of 131 potato and 32 tomato isolates was determined. Forty-nine isolates from potatoes and 11 from tomatoes were analyzed for their Gpi phenotype. A subset of 35 isolates was evaluated for mitochondrial (mtDNA) polymorphisms. A sample of 146 isolates was tested for sensitivity to the fungicide metalaxyl, and most isolates (64%) were moderately sensitive. Fifty-nine isolates were classified as A1 mating type and 103 as A2. One isolate behaved as both A1 and A2 mating type. All tomato isolates were A1 mating type and presented the 86/100 pattern for the enzyme GPI and mtDNA Ib, indicating that these isolates belong to the US-1 clonal lineage. Of the 131 potato isolates, 103 were A2, 27 were A1 and one was A1/A2 mating type. Among the potato isolates 27 exhibited the Gpi phenotype 100/100, the same as BR-1, and 20 were 86/100, the same as US-1. Potato isolates presented the mitochondrial haplotypes Ia (74%) and IIa (26%). The data suggest the presence of only the BR-1 clonal lineage on potatoes in the states of PR and SC. However, in the state of RS, more than one clonal lineage was observed infecting potatoes, and there may be sexual reproduction between the lineages. 相似文献
20.
Giani M.B. Bohm Segundo Urquiaga Gustavo R. Xavier Cesar V. Rombaldi 《Soil biology & biochemistry》2009,41(2):420-422
Over half of the 21 Mha of soybean planted in Brazil is now transgenic glyphosate-resistant (GMRR). A field experiment was carried out to investigate whether the application of glyphosate or imazethapyr to the GMRR variety reduced the input of N2 fixation (BNF). No effects on yield, total N accumulation, nodulation and BNF (δ15N) could be assigned to the genetic modification of the plant. Imazethapyr reduced soybean yield but had no significant effect on BNF. Even though yields were not affected by glyphosate, the significant reduction of nodule mass and BNF to the GMRR suggests that the use of this herbicide could lead to an increased dependence on soil N and consequently an eventual decrease of SOM reserves. 相似文献