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151.
Fernando Ibañez Tania Taurian Jorge Angelini Maria Laura Tonelli Adriana Fabra 《Soil biology & biochemistry》2008,40(2):537-539
Our previous studies of the native rhizobial population associated with peanut nodules in the Córdoba soils of Argentina revealed that this population is highly diverse and includes slow- and fast-growing isolates. The native fast-growing isolates NCHA22 and NET30 were selected on the basis of their plant growth promoting properties and their chromosomal genotypes were determined by 16S rDNA sequencing. NCHA22 and NET30 16S rDNA alleles were found to cluster with those of Rhizobium tropici group IIB and Rhizobium giardinii bv. giardinii strain H152, respectively. We have now characterized these isolates by analyzing the glnA and nifH genes to clarify their taxonomic position. These studies confirmed that fast-growing isolates belonging to species earlier described as bean symbionts were obtained from nodules of a leguminous plant that has been described as efficiently nodulated exclusively by slow-growing rhizobial strains. 相似文献
152.
Catarina R. Marques Nelson Abrantes Daniela R. de Figueiredo Mário J. Pereira Fernando Gonçalves 《Water, air, and soil pollution》2008,189(1-4):49-59
Rice fields represent important production rates in Portugal. However, the intensive soil management and the exploitation of agrochemicals may pose a threat to nontarget organisms. Hence, the present work regards the toxicity screening of surface waters and sediment elutriates collected during the drainage of fields in the vicinity of a rice paddy (Quinta do Seminário, Soure, Portugal): 1. in River Pranto (RP), the river from which the field irrigation water is canalized; 2. inside the rice paddy, from the main drainage channel – Vala de Enxugo (VE). For that purpose, it was used a combination of physico-chemical analyses and bioassays with two green algae species – Pseudokirchneriella subcapitata and Chlorella vulgaris. The chemical screening showed an apparent absence of xenobiotics in sediment samples, while no pesticides were found within the chemical contaminants detected in water samples. The nutrient load reflected low levels of inorganic contamination. Bioassays revealed that P. subcapitata was more sensitive to the overall physico-chemical conditions in natural samples than C. vulgaris, being its growth inhibited under water samples from both sites. On a whole, water samples, mainly those from the main irrigation/drainage channel of the rice fields (VE), were more deleterious to microalgae than those from RP or any of the elutriates. 相似文献
153.
Fabien Thomas Jean-Pierre Rossi Thibaud Decaëns Michel Grimaldi Patrick Lavelle Paulo Fernando da Silva Martins Evelyne Garnier-Zarli 《European Journal of Soil Biology》2008,44(5-6):545
Soil ecosystem engineers produce biogenic structures (casts, mounds, galleries) that strongly affect soil processes. A comparative analysis of the physical characteristics of the casts produced by the earthworm Andiodrilus pachoensis was carried out in four pastures sowed with Brachiaria brizantha and four primary forests on the deforestation front of the Amazonian forest. In both systems, we recorded surface cast density and spatial patterns as well as surface cast physical properties. Cast and vegetation distributions were mapped within plots of sizes ranging from 25 to 50 m2, and cast production was monitored during 2 months. Cast spatial distribution varied greatly among plots and across spatial scales ranging from regular at small spatial scales (0–20 cm) to clumped for larger distance ranges (>80 cm). Cast density was not significantly correlated with grass tuft density and their production was independent from the presence of grass tufts in pastures or litter quantity in forests. Although bulk soil properties (pH, C content, structural stability, etc) differed between pastures and forests, cast physical properties did not differ significantly among the studied ecosystem. 相似文献
154.
Alvarez B Revilla C Doménech N Pérez C Martínez P Alonso F Ezquerra A Domíguez J 《Veterinary research》2008,39(2):13
Toll-like receptors (TLR) are a group of pattern recognition molecules that play a crucial role in innate immunity. TLR2 recognises a variety of microbial components leading to the development of inflammatory and immune responses. To characterise the expression and functional properties of porcine TLR2 (pTLR2), we have raised a panel of monoclonal antibodies (mAb) against this molecule. Mouse 3T3 cell transfectants expressing pTLR2 were used for immunisation of mice. The specificity of these antibodies was confirmed by their reactivity with CHO cells transfected with pTLR2 but not with pTLR4 or with non-transfected cells. Using one of these mAbs, named 1H11, pTLR2 was found on cells of the innate immune system, including monocytes, macrophages, and granulocytes, but not on peripheral blood lymphocytes. Staining of tissue sections showed that pTLR2 is also expressed on epithelial cells lining the tracheobronchial and intestinal tracts, bile ducts in the liver and renal tubules, and on the basal layer of the epidermis. This distribution is consistent with a surveillance function at entry sites, allowing for early detection of microbial invasion. 相似文献
155.
156.
157.
Hugo Vilhena Asta Tvarijonaviciute Jos J. Cern Ana C. Figueira Snia Miranda Ana Ribeiro Ana Canadas Patrícia Dias‐Pereira Camila P. Rubio Lorena Franco Fernando Tecles Ricardo Cabeas Josep Pastor Ana C. Silvestre‐Ferreira 《Veterinary and comparative oncology》2019,17(3):394-406
Acute phase proteins (APP) and biomarkers of oxidative status change in human and canine mammary tumours, however, they have not been studied in feline mammary tumours. The aims of this study were to investigate the APP and antioxidant responses in feline malignant mammary tumours, to evaluate their relation with tumour features, and to assess their prognostic value. Serum amyloid A (SAA), haptoglobin (Hp), albumin, butyrylcholinesterase (BChE), insulin‐like growth factor1 (IGF1), paraoxonase1 (PON1), total serum thiols (Thiol), glutathione peroxidase (GPox) and total antioxidant capacity determined by different assays, including trolox equivalent antioxidant capacity assessed by two different methodologies (TEAC1/2), ferric reducing ability of plasma (FRAP), and cupric reducing antioxidant capacity (CUPRAC), were determined in serum of 50 queens with spontaneous mammary carcinomas and of 12 healthy female cats. At diagnosis, diseased queens presented significantly higher SAA and Hp, and lower albumin, BChE, GPox, TEAC1, TEAC2 and CUPRAC than controls. Different tumour features influenced concentrations of APP and antioxidants. Increases in serum Hp, and decreases in albumin, Thiol and FRAP were significantly associated with neoplastic vascular emboli, metastasis in regional lymph nodes and/or in distant organs. Distant metastasis development during the course of the disease was associated with increases in SAA and TEAC1. At diagnosis, decreased albumin was associated with a longer survival, and BChE <1.15 μmoL/mL.minute was associated with a shorter survival time on multivariate analysis. Feline malignant mammary tumours are associated with an APP response and oxidative stress, and different tumour features influence the inflammatory response and the oxidative damage. Furthermore, some of these analytes proved to have prognostic value. 相似文献
158.
Sarah E.Dickinson Michelle F.Elmore Lisa Kriese-ANDerson Joshua B.Elmore Bailey N.Walker Paul W.Dyce Soren P.Rodning Fernando H.Biase 《畜牧与生物技术杂志(英文版)》2019,(2)
Background: Artificial insemination is a preferred breeding method for beef heifers as it advances the genetic background, produces a predictive and profitable calving season, and extends the heifer's reproductive life span.As reproductive efficiency in heifers is key for the success of beef cattle production systems, following artificial insemination, heifers are exposed to a bull for the remainder of the breeding season. Altogether, up to 95% of heifers might become pregnant in their first breeding season. Heifers that do not become pregnant at the end of the breeding season represent an irreparable economical loss. Additionally, heifers conceiving late in the breeding season to natural service, although acceptable, poses serious losses to producers. To minimize losses due to reproductive failure, different phenotypic parameters can be assessed and utilized as selection tools. Here, we tested the hypothesis that in a group of pre-selected heifers, records of weaning weight, age at weaning, age at artificial insemination, and age of dam differ among heifers of varied reproductive outcomes during the first breeding season.Results: None of the parameters tested presented predictive ability to discriminate the heifers based on the response variable(‘pregnant to artificial insemination', ‘pregnant to natural service', ‘not pregnant'). Heifers categorized with body condition score = 6 and reproductive tract score ≥ 4 had the greatest proportion of pregnancy to artificial insemination(49% and 44%, respectively). Furthermore, it was notable that heifers presenting body condition score = 6 and reproductive tract score = 5 presented the greatest pregnancy rate at end of the breeding season(89%). Heifers younger than 368 d at the start of the breeding season did not become pregnant to artificial insemination. Those young heifers had 12.5% chance to become pregnant in their first breeding season,compared to 87.5% if the heifers were older than 368 days.Conclusion: Our results suggest that beef heifers with body condition score = 6 and reproductive tract score ≥ 4 are more likely to become pregnant to artificial insemination. Careful assessment should be undertaken when developing replacement heifers that will not reach 12 months of age by the beginning of the breeding season. 相似文献
159.
Derossi R Medeiros U de Almeida RG Righetto FR Frazílio FO 《Veterinary journal (London, England : 1997)》2008,178(2):294-297
The aim of the study was to evaluate and compare the effects of caudal epidural administration of meperidine (MP), lidocaine (LD), and a combination of the two (MPLD) in six mature saddle horses. Horses were randomly assigned to receive three treatments (MP 0.3 mg/kg; LD 0.2 mg/kg; and MPLD: MP 0.3 mg/kg and LD 0.2 mg/kg), with at least 1 week between treatments. Drugs were injected into the epidural space between the first and second coccygeal areas in conscious standing horses. Analgesia, ataxia, sedation, cardiovascular and respiratory effects, and rectal temperature were recorded at different intervals before (baseline) and after administration. Epidural administration of MPLD resulted in a longer duration of analgesia of the tail, perineum, and upper hind limb regions than did administration of MP or LD alone. 相似文献
160.
Danilo V. G. Vieira Jos H. V. Silva Fernando G. P. Costa Thiago S. Melo Matheus R. Lima Danilo T. Cavalcante Jos G. de Vargas Júnior Talita P. Bonaparte Lorena C. Oliveira 《Journal of animal physiology and animal nutrition》2019,103(1):116-124
Experiment I: T1‐1 = basal diet with 25% crude protein (CP) + limiting amino acids (LA); T1‐2 = 20% CP + LA; T1‐3 = 20% CP + LA + L‐glycine; T1‐4 = 20% CP + LA + L‐glutamate; T1‐5 = 20% CP + LA + L‐glycine + L‐glutamate. Experiment II: T2‐1 = basal diet with 22% CP + LA; T2‐2 = 20% CP + LA; T2‐3 = 17.6% CP + LA + L‐glycine; T2‐4 = 17.6% CP + LA + L‐glutamate; T2‐5 = 17.6% CP + LA + L‐glycine + L‐glutamate. The reduction of dietary protein based on the concept of ideal protein decreases nitrogen excretion in quails when L‐glycine is added to the diets. Quails fed diets supplemented with L‐glutamate as the non‐specific nitrogen source equivalent to the nitrogen level of the control diet had increased nitrogen excretion. However, quails had reduced nitrogen excretion in both experiments when L‐glycine was added to diets with L‐glutamate. Carcass fat was increased by reducing dietary protein, but fat deposition was reduced by adding L‐glutamate and L‐glycine, or both. The dietary addition of L‐glutamate and L‐glycine in quails based on the ideal protein concept is not necessary (Exp. I). Although the total nitrogen, electrolytic balance and glycine level were adjusted in diets, quails had decreased performance. Therefore, other hypotheses besides protein reduction need to be studied (Exp. II). Protein reduction with supplementation of only limiting essential amino acids does not affect quail performance. Dietary addition of L‐glycine reduces nitrogen excretion. 相似文献