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121.
Rocha M.A. Barbosa E.F. Guedes R.M.C. Lage A.P. Leite R.C. Gouveia A.M.G. 《Veterinary research communications》1999,23(2):133-141
Bovine herpesvirus 1 (BHV-1) is frequently associated with abortion in naturally and experimentally infected cattle. Most of the virus isolation and immunofluorescent antibody protocols described in the literature for detecting BHV-1 in bovine foetuses are rather laborious, costly and time-consuming. The detection is described of BHV-1 in the tissues of a naturally aborted bovine foetus by a nested PCR assay with no further hybridization procedures.Optimal results were achieved by filtering the foetal tissues on a chromatography column before DNA extraction, by using two pairs of primers in a nested PCR and by evaluating the amplification products on silver-stained polyacrylamide gels.This nested PCR was faster and easier to perform than the virus isolation test. To our knowledge, this is the first time that BHV-1 has been detected in the tissues of a naturally infected bovine foetus by means of a nested PCR. The test seems to be a practical alternative for rapid detection of BHV-1 in bovine foetus. 相似文献
122.
Henrique Nery Cipriani Ana Rosa Ribeiro Bastos Janice Guedes de Carvalho Alisson Lucrécio da Costa Nilma Portela Oliveira 《Journal of plant nutrition》2013,36(11):1618-1638
A greenhouse experiment was carried out to evaluate chromium (Cr) toxicity in urograndis (Eucalyptus urophylla S. T. Blake x grandis W. Hill ex. Maiden). Chromium nitrate was amended to Clark's nutrient solution (0.00, 0.04, 0.08, 0.16, 0.32 and 0.64 mmol L?1 Cr), which was used to breed one urograndis cutting per pot (four replications). Regression analysis revealed that Cr rates of 0.08 mmol L?1 or higher significantly decreased (P < 0.01) dry matter yield of shoot and root. Chromium accumulation order in plant was: root > stem > leaves. Critical Cr toxicity level in leaves was 0.74 mg kg?1. Uptake and translocation of nutrients were affected differently by Cr. Mostly have their uptake reduced due to root damage. Magnesium, iron and manganese translocation increases, supposedly to maintain normal photosynthetic activity. Wilting is the main visual symptom of Cr toxicity. Urograndis may be suitable for contaminated sites phytostabilization and receive industrial waste fertilization. 相似文献
123.
Alonso GP Guedes Elaine P Rude Mathur S Kannan 《Veterinary anaesthesia and analgesia》2013,40(5):512-516
ObjectiveTo investigate the CD38/cADPR signaling pathway as possible underlying mechanism of the effects of medetomidine on insulin and glucose homeostasis.AnimalsThirty–two C57BL/6 mice of both sexes.MethodsWild–type (WT) and CD38–knockout (CD38?/?) mice received medetomidine (50 μg kg?1) or a similar volume of 0.9% NaCl (control) by intraperitoneal (IP) injection (each group n = 8). The mice were euthanized 45 minutes later with sodium pentobarbital IP and blood was sampled via cardiac puncture. Insulin and glucose concentrations were measured by radioimmunoassay and by the oxygen rate method, respectively. Data were analyzed with anova and Bonferroni post hoc (5% significance) and are shown as mean ± SD.ResultsPlasma insulin and glucose concentrations were similar between WT and CD38?/? mice under control conditions. As compared to controls, medetomidine administration produced a statistically significant decrease in plasma insulin concentrations in the WT mice whereas the decrease in the CD38?/? mice was not statistically significant. Correspondingly, medetomidine caused a significantly greater increase in plasma glucose concentrations in the WT than in the CD38?/? mice.ConclusionThe CD38/cADPR signaling pathway may be one underlying mechanism of the glucose and insulin effects of the alpha–2 adrenergic receptor agonist medetomidine and likely other drugs of its’ class. 相似文献
124.
Elka Fabiana Aparecida Almeida Janice Guedes de Carvalho Jussara Ellen Morais Frazão Nilma Portela Oliveira 《Journal of plant nutrition》2015,38(5):663-674
The objective of this work was to describe the nutrition deficiencies symptoms in calla lily (Zantedeschia aethiopica). Seedlings were maintained in complete nutrition solution and with omission of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), iron (Fe), boron (B), and manganese (Mn), totalizing 10 treatments. The first deficiencies symptoms appeared in plants cultivated in N omission, followed by treatments with omission of S, B, K, Fe, P, and Ca. Individual omissions of N and B prevented blooming, while S and K deficiencies resulted in production of small and greenish inflorescences with deformities. Reddish spots in leaves were observed in plants growing in solution with omission of P. Root development was affected either by omission of B or S. Death of the apical bud and formation of a “black center” in calla lily rhizome was caused by B deficiency. Nitrogen, B, and S are the most required nutrients for calla lily plants. The mineral composition of calla lily leaves is affected by nutritional deficiencies 相似文献
125.
Moreira MD Picanço MC Barbosa LC Guedes RN Barros EC Campos MR 《Pest management science》2007,63(6):615-621
This work aimed at identifying plant compounds with insecticidal activity against Diaphania hyalinata (L.) (Lepidoptera: Pyralidae), Musca domestica (L.) (Diptera: Muscidae), Periplaneta americana (L.) (Blattodea: Blattidae) and Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae). The plant species used were: basil (Ocimum selloi Benth.), rue (Ruta graveolens L.), lion's ear (Leonotis nepetaefolia L.), Jimson weed (Datura stramonium L.), 'baleeira' herb (Cordia verbenaceae L.), mint (Mentha piperita L.), wild balsam apple (Mormodica charantia L.) and billy goat weed (Ageratum conyzoides L.). Firstly, the insecticidal activities of hexane and ethanol plant extracts were evaluated against adults of R. dominica. Among them, only the hexane extract of A. conyzoides showed insecticidal activity. The hexane extract of this plant species was therefore fractionated by silica gel column chromatography to isolate and purify its bioactive chemical constituents. Three compounds were identified using IR spectra, (1)H NMR, (13)C NMR, HMBC and NOE after gel chromatography: 5,6,7,8,3', 4', 5'-heptamethoxyflavone, 5,6,7,8,3'-pentamethoxy-4', 5'-methylenedioxyflavone and coumarin. The complete assignment of (13)C NMR to 5,6,7,8,3'-pentamethoxy-4', 5'-methylenedioxyflavone was successfully made for the first time. 5,6,7,8,3'-Pentamethoxy-4', 5'-methylenedioxyflavone did not show any insecticidal activity against the four insect species tested. 5,6,7,8,3', 4', 5'-Heptamethoxyflavone showed low activity against D. hyalinata and R. dominica and was not toxic to M. domestica or P. americana. In contrast, coumarin showed insecticidal activity against all four insect pest species tested, with the following order of susceptibility: R. dominica < P. americana < D. hyalinata < M. domestica after 24 h exposure. 相似文献
126.
127.
Mara H. Saalfeld Daniela I. B. Pereira Jessica L. Borchardt Regis T. Sturbelle Matheus C. Rosa Marcio C. Guedes Marcia A. Gularte Fábio P. Leivas Leite 《Animal Science Journal》2014,85(11):963-967
Colostrum silage is an anaerobic fermentation methodology of excess farm colostrum used to conserve and provide as milk replacement for calves. The present study aimed to evaluate the levels of immunoglobulins present in bovine colostrum silage and its absorption by newborn calves. The concentration of immunoglobulins was determined in fresh colostrum and colostrum silage stored for 12 months. The absorption of immunoglobulins by calves was assessed immediately after birth and 24 h after colostrum silage intake. The immunoglobulin levels were evaluated by ELISA. The results highlighted that colostrum silage kept similar levels of immunoglobulins as the ones in colostrum in natura, and can be transferred to newborn calves with similar amounts to calves fed with colostrum in natura. It is concluded that colostrum silage keeps viable immunoglobulins, and is able to transfer passive immunity to newborn calves. 相似文献
128.
129.
Tramadol is a centrally acting analgesic with opioid and monoaminergic actions. Its clinical effects have been well characterized in humans, where it has been in use for many years, but little is known for veterinary species. This study evaluated the sedative, emetic, thiopental‐sparing and intraoperative respiratory and hemodynamic effects of tramadol in comparison to morphine for pre‐medication of dogs undergoing orthopedic surgery under halothane anesthesia. Sixteen adult, healthy, mixed breed dogs (8.0 ± 2.6 kg) were studied. Eight dogs were pre‐medicated with tramadol (1.0 mg kg‐1 IM) and the other eight with morphine (1.0 mg kg–1 IM). After 20 minutes, anesthesia was induced with thiopental and subsequently maintained with halothane in oxygen using a Bain system, with spontaneous respiration. Degree of sedation and occurrence of emesis were evaluated after pre‐anesthetic medication. Dose of thiopental necessary for tracheal intubation was compared between the two groups. Arterial blood gas analyzes were done before pre‐medication and at 60 minutes of anesthesia. Heart rate and noninvasive arterial blood pressure were recorded before pre‐medication and every 10 minutes during anesthesia. Observer was blinded of the treatment given for each dog. Tramadol produced no visible sedation and no vomiting, while morphine induced a moderate degree of sedation in all dogs and vomiting in 62% of them. Dogs pre‐medicated with tramadol required significantly more thiopental (17 ± 3.8 mg kg–1) for induction of anesthesia than those pre‐medicated with morphine (12 ± 1.8 mg kg–1). Pre‐medication with morphine was associated with significantly higher PaCO2 and lower pH at 60 minutes of anesthesia. The remaining respiratory parameters and the hemodynamic variables were similar between the two groups. In conclusion, dogs pre‐medicated with tramadol at 1 mg kg–1 IM do not become visibly sedated and require a greater amount of thiopental for induction of anesthesia than pre‐medication with morphine. As intraoperative respiratory function is better preserved with tramadol, it may be useful for pre‐medication of respiratory compromised patients. 相似文献