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941.
Angela A. Franzen João A. T. Pigatto Fernando C. Abib Luciane Albuquerque José L. Laus 《Veterinary ophthalmology》2010,13(4):222-226
The purpose of this study was to investigate the effect of age on endothelial morphology and morphometry in cats. The corneal endothelium was studied using a contact specular microscope. A total of 18 cats (Felis catus Linnaeus, 1758) were evaluated in this study. The subjects were divided into three groups of six cats each in function of age: G1 (1 to 3 months old), G2 (5 to 12 months old), and G3 (24 to 40 months old). The examination presented data as endothelial cell density (ECD), average cell area, corneal thickness, polymegathism, and pleomorphism. Results revealed ECD decrease in corneas of normal cats with age, as well as a corresponding increase in endothelial cell area and pleomorphism. The present work suggests that the endothelial parameters evaluated change with advancing age. 相似文献
942.
Elisangela P. Freitas Sheila C. Rahal Carlos R. Teixeira Jorge V.L. Silva Pedro Y. Noritomi Carlos H.S. Villela Seizo Yamashita 《The Canadian veterinary journal. La revue veterinaire canadienne》2010,51(3):267-270
An approximately 9-month-old fox (Pseudalopex vetulus) was presented with malocclusion and deviation of the lower jaw to the right side. Orthodontic treatment was performed using the inclined plane technique. Virtual 3D models and prototypes of the head were based on computed tomography (CT) image data to assist in diagnosis and treatment. 相似文献
943.
R.C. Sesana A.B. Bignardi R.R.A. Borquis L. El Faro F. Baldi L.G. Albuquerque H. Tonhati 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2010,127(5):369-376
The objective of this work was to estimate covariance functions for additive genetic and permanent environmental effects and, subsequently, to obtain genetic parameters for buffalo’s test‐day milk production using random regression models on Legendre polynomials (LPs). A total of 17 935 test‐day milk yield (TDMY) from 1433 first lactations of Murrah buffaloes, calving from 1985 to 2005 and belonging to 12 herds located in São Paulo state, Brazil, were analysed. Contemporary groups (CGs) were defined by herd, year and month of milk test. Residual variances were modelled through variance functions, from second to fourth order and also by a step function with 1, 4, 6, 22 and 42 classes. The model of analyses included the fixed effect of CGs, number of milking, age of cow at calving as a covariable (linear and quadratic) and the mean trend of the population. As random effects were included the additive genetic and permanent environmental effects. The additive genetic and permanent environmental random effects were modelled by LP of days in milk from quadratic to seventh degree polynomial functions. The model with additive genetic and animal permanent environmental effects adjusted by quintic and sixth order LP, respectively, and residual variance modelled through a step function with six classes was the most adequate model to describe the covariance structure of the data. Heritability estimates decreased from 0.44 (first week) to 0.18 (fourth week). Unexpected negative genetic correlation estimates were obtained between TDMY records at first weeks with records from middle to the end of lactation, being the values varied from ?0.07 (second with eighth week) to ?0.34 (1st with 42nd week). TDMY heritability estimates were moderate in the course of the lactation, suggesting that this trait could be applied as selection criteria in milking buffaloes. 相似文献
944.
分子标记法和形态学特征对杏仁栽培种及野生种基因型的遗传关系构建的辨别 总被引:1,自引:0,他引:1
Karim Sorkheh Behrouz Shiran Soghra Kiani Nazanin Amirbakhtiar Sadegh Mousavi Vahid Rouhi Shahram Mohammady-D Thomas M.Gradziel Lyudmyla V.Malysheva-Otto Pedro Martínez-Gómez 《林业研究》2009,20(3):183-194
应用23个形态学特征,19个扩增片段长度多态性(AFLP)引物组合,80个随机扩增多态DNA(RAPD)引物和32个简单序列重复(SSR)引物对,比较三种分子标记法在29个杏仁栽培种和3个野生种遗传关系构建中的信息景和效率.根据预期杂合度的评价,与AFLPs和RAPDs相比,SSRs具有较高水平的多态性和较大的信息量.AFLPs预期朵合度值最低,但其辨别效率值最高,因为AFLPs能揭示每个反应中的大量条带,导致各种类型的多样性指数均较高.三种分子标记法对杏仁基因型的辨别效率均较高,只是SSRs无法辨别‘Monagha'和‘Sefied'杏仁基因型.三种分子标记法基因型相似性相关系数统计上显著,但SSR数据要低于RAPDs和AFLPs的值.尽管三种分子标记法树形图拓扑结构存在一些差异,但相似性水平均较高.SSRs、RAPDs和AFLPs的系统树图及其综合数据都能依据地理散布反映大多数栽培种的关系.AMOVA检测到每个地理组中栽培种和野生种的变异.辅助程序分析表明,实验所应用的标记物数量足以保证基因相似性估计的可靠性和标记法间的比较是有意义的. 相似文献
945.
Armillaria mellea (Vahl ex Fr) Kummer is an aggressive pathogen which causes white root rot in a wide range of hosts. Most chemicals tested so far against Armillaria, both in vitro and in the field, have not been effective in reducing fungal growth and/or preventing plant decline and mortality. In the present work the effects of four DMI (sterol demethylation inhibitor) fungicides, cyproconazole, hexaconazole, propiconazole and tetraconazole, and another six downwardly mobile systemic chemicals, azoxystrobin, cubiet (copper bis(ethoxy-dihydroxy-diethylamino)sulfate), fosetyl-Al, potassium phosphite, sodium tetrathiocarbonate (STTC) and 2-(thiocyanomethylthio)benzothiazole (TCMTB), on the mycelial growth of A. mellea were compared and evaluated; the product yielding the best results in in vitro experiments was selected to determine its efficacy in preventing decline and mortality of grapevines in the field. Best results on in vitro fungal growth reduction were obtained with the four azoles tested, in particular with cyproconazole and hexaconazole, achieving 67-72% mycelial growth inhibition at the lowest dose. Results obtained in the field showed that a dose of 50 mg AI litre(-1) of cyproconazole once or twice a year was efficient in controlling the disease even in vines seriously affected by the pathogen. However, further research is required to study minimum effective doses, residual effects and the convenience of the application of annual dressings in damaged vineyards, so as to gradually reduce the pathogen inoculum potential in soil and control the disease while reducing chemical residues in the plant and preventing development of fungal resistance. 相似文献
946.
Vicente de P.R. Silva João H.B.C. Campos Madson T. Silva Pedro V. Azevedo 《Agricultural Water Management》2010,97(11):1760-1768
This study evaluated the effects of climate change on cowpea bean crop grown in northeastern Brazil based on the reports of the Intergovernmental Panel on Climate Change (IPCC). The water balance model combined with Geographic Information System techniques was used to identify regional areas where the cowpea bean crop will suffer yield reduction due to climate changes. Model input variables were: rainfall, crop coefficients, potential evapotranspiration and duration of the crop cycle. A limit value of 0.5 was adopted for the water requirement satisfaction index (WRSI), being the ratio of actual to maximum evapotranspiration. The acceptable seeding date was defined as the date at which the water balance simulation presented a WRSI value greater than the limit value, with a frequency of at least 80%. An increase in air temperature will cause a significant reduction in the areas currently favorable to cowpea bean crop growth in northeastern Brazil, and it is recommended that bean varieties better suited to high-temperature conditions should be planted. 相似文献
947.
Bruna Bitencourt Da Costa Lis Santos Marques Paula Graziela Lassen Rmulo Batista Rodrigues Helen Tais Da Rosa Silva Jos Cludio Fonseca Moreira Danilo Pedro Streit 《Aquaculture Research》2020,51(2):455-464
The cryopreservation promotes cellular damage that could compromise sperm quality in terms of motility and fertility rates, which may be caused by oxidative stress. Thus, the aim of this study was to assess the effects of cysteine addition on post‐thaw sperm quality, DNA damage and indices of oxidative stress of the South American silver catfish (Rhamdia quelen) sperm, compared with the cryoprotectant solution without cysteine addition. Sperm collected from five males were cryopreserved in cryoprotectant solution (fructose 50 g/L, powdered milk 50 g/L and methanol 100 ml/L) containing different cysteine concentrations (0, 2.5, 5, 10 and 20 mM). After thawing, the following were measured: sperm motility, morphology, sperm viability, DNA damage, lipid peroxidation, concentration of carbonyl and sulfhydryl groups and the activity of SOD, CAT, GST and GPx enzymes. The lowest sperm motility was determined for semen cryopreserved with addition of 20 mM of cysteine. The control group had the lowest DNA damage and lipid peroxidation. The findings of this study show that cysteine addition had no positive effect on evaluated parameters. Therefore, the concentrations tested are not recommended for the supplementation of cryoprotectant solution for semen of R. quelen. 相似文献
948.
Susana Carvalho Manuela Falcão João Cúrdia Ana Moura Dalila Serpa Miguel B. Gaspar Maria Teresa Dinis Pedro Pousão-Ferreira Luís Cancela da Fonseca 《Aquaculture International》2009,17(6):571-587
The present work aims to assess the importance of settlement ponds (SP) in semi-intensive fish farms by studying benthic dynamics
in an aquaculture fish farm, more specifically in the water reservoir (WR) and SP and also in production (P) and nonproduction
(C) ponds during a 16-month period. In Portugal, a SP is only mandatory for intensive fish farms, and another objective of
the present study is to assess the importance of these areas in semi-intensive fish farms. The WR was the area with highest
diversity and evenness, as well as the higher number of exclusive taxa and taxa sensitive to organic enrichment. P and SP
samples showed signs of higher disturbance levels, emphasized namely by the association of the opportunistic annelids Capitella spp. and Tubificidae. However, the benthic data from SP points to lower disturbance levels than P both due to an increase
in the percentage of sensitive taxa observed in June and October 2004 and by the association of this latter sample with water
reservoir samples as evidenced by canonical correspondence analysis. Moreover, a higher and increasing number of taxa when
compared with the P area were also observed. Therefore, in semi-intensive fish farms, where effluents from P ponds are directly
discharged to the lagoon, the potential environmental impacts would be more severe. In conclusion, the imposition of SP in
semi-intensive fish farms should be considered, especially because most fish farms are located within relevant wetland areas. 相似文献
949.
950.
Pedro Albuquerque Inês Ribeiro Sofia Correia Ana Paula Mucha Paula Tamagnini Andreia Braga-Henriques Maria de Ftima Carvalho Marta V. Mendes 《Marine drugs》2021,19(11)
The deep-sea constitutes a true unexplored frontier and a potential source of innovative drug scaffolds. Here, we present the genome sequence of two novel marine actinobacterial strains, MA3_2.13 and S07_1.15, isolated from deep-sea samples (sediments and sponge) and collected at Madeira archipelago (NE Atlantic Ocean; Portugal). The de novo assembly of both genomes was achieved using a hybrid strategy that combines short-reads (Illumina) and long-reads (PacBio) sequencing data. Phylogenetic analyses showed that strain MA3_2.13 is a new species of the Streptomyces genus, whereas strain S07_1.15 is closely related to the type strain of Streptomyces xinghaiensis. In silico analysis revealed that the total length of predicted biosynthetic gene clusters (BGCs) accounted for a high percentage of the MA3_2.13 genome, with several potential new metabolites identified. Strain S07_1.15 had, with a few exceptions, a predicted metabolic profile similar to S. xinghaiensis. In this work, we implemented a straightforward approach for generating high-quality genomes of new bacterial isolates and analyse in silico their potential to produce novel NPs. The inclusion of these in silico dereplication steps allows to minimize the rediscovery rates of traditional natural products screening methodologies and expedite the drug discovery process. 相似文献