应用固相萃取高效液相色谱-质谱法测定水中多种农药残留   总被引：1，自引：0，他引：1  

申义珍  J.L.Martinez Vidal  R.Romero Gonealez  M.E.Hernandez Torres 《农业环境科学学报》2006,(Z2)

应用HLB固相萃取高效液相色谱-质谱法同时测定水中杀虫剂、杀菌剂、除草剂、杀螨剂、杀线虫剂等5类30种农药残留,标准曲线决定系数r2均大于0.99,标准添加回收率达76%￣107%,平均为87.9%。在实际测定的10个水样中,有个水样的杀铃脲(Triflumuron)含量超标。  相似文献   

In vitro activity of olive oil polyphenols against Helicobacter pylori     

Romero C  Medina E  Vargas J  Brenes M  De Castro A 《Journal of agricultural and food chemistry》2007,55(3):680-686

Helicobacter pylori is linked to a majority of peptic ulcers and to some types of gastric cancer, and resistance of the microorganism to antibiotic treatment is now found worldwide. Virgin olive oil is an unrefined vegetable oil that contains a significant amount of phenolic compounds. Under simulated conditions, we have demonstrated that these substances can diffuse from the oil into the gastric juice and be stable for hours in this acidic environment. In vitro, they exerted a strong bactericidal activity against eight strains of H. pylori, three of them resistant to some antibiotics. Among the phenolic compounds, the dialdehydic form of decarboxymethyl ligstroside aglycon showed the strongest bactericidal effect at a concentration as low as 1.3 microg/mL. Although the experimental conditions are different from other reported works, this bactericidal concentration is much lower than those found for phenolic compounds from tea, wine, and plant extracts. These results open the possibility of considering virgin olive oil a chemopreventive agent for peptic ulcer or gastric cancer, but this bioactivity should be confirmed in vivo in the future.  相似文献   

Comparison of the concentrations of phenolic compounds in olive oils and other plant oils: correlation with antimicrobial activity     

Medina E  de Castro A  Romero C  Brenes M 《Journal of agricultural and food chemistry》2006,54(14):4954-4961

The antimicrobial activity of different edible vegetable oils was studied. In vitro results revealed that the oils from olive fruits had a strong bactericidal action against a broad spectrum of microorganisms, this effect being higher in general against Gram-positive than Gram-negative bacteria. Thus, olive oils showed bactericidal activity not only against harmful bacteria of the intestinal microbiota (Clostridium perfringens and Escherichia coli) also against beneficial microorganisms such as Lactobacillus acidophilus and Bifidobacterium bifidum. Otherwise, most of the foodborne pathogens tested (Listeria monocytogenes, Staphylococcus aureus, Salmonella enterica, Yersinia sp., and Shigella sonnei) did not survive after 1 h of contact with olive oils. The dialdehydic form of decarboxymethyl oleuropein and ligstroside aglycons, hydroxytyrosol and tyrosol, were the phenolic compounds that statistically correlated with bacterial survival. These findings were confirmed by testing each individual phenolic compound, isolated by HPLC, against L. monocytogenes. In particular, the dialdehydic form of decarboxymethyl ligstroside aglycon showed a potent antimicrobial activity. These results indicate that not all oils classified as "olive oil" had similar bactericidal effects and that this bioactivity depended on their content of certain phenolic compounds.  相似文献   

Maturation and Spawning of Blue Shrimp Penaeus stylirostris (Stimpson) under Hypersaline Conditions     

Karl-Heinz  Holtschmit Juan Manuel  Romero 《Journal of the World Aquaculture Society》1991,22(1):45-50

Maturation and spawning of blue shrimp Penaeus stylirostris were obtained in hypersaline and turbid water. Results indicate that number of spawnings per female and percentage of viable spawnings are similar to those reported under "standard" conditions by other investigators. However, the number of nauplii produced was 50 to 75% less. A significant correlation was observed between reproductive activity and lunar cycles, showing peak activity at three to four days following new moon. Additionally, working with records of individual females, the number of spawnings per female was found to be extremely variable, with intervals between consecutive spawnings non-uniform. Instead, they tended to group in pairs with less than six days between spawnings, followed by a variable period of time (usually more than 12 days) before the paired spawnings were repeated.  相似文献   

Sequence analysis of feline caliciviruses isolated from the oral cavity of clinically normal domestic cats (Felis catus) in Florida     

M. L. Weeks  A. Gallagher  C. H. Romero 《Research in veterinary science》2001,71(3):223-225

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Effect of a killed whole Neospora caninum tachyzoite vaccine on the crude abortion rate of Costa Rican dairy cows under field conditions     

Romero JJ  Pérez E  Frankena K 《Veterinary parasitology》2004,123(3-4):149-159

A standard field trial was carried out to assess the effect of a commercial Neospora-vaccine based on whole killed tachyzoites (Bovilis-Neoguard, Intervet) on the abortion rate. Eight hundred and seventy-six cows, over 2.5 months pregnant, belonging to 25 Costa Rican dairy herds, were used in the analysis. For each cow vaccinated, a cow of the same herd, breed and age category, was selected as control. The period of administration of treatments extended from June to November of 2000. The treatments were administered in two, 5-ml doses 1 month apart, the first dose given between day 75 and 90 of gestation. The incidence of abortion among all treated cows was of 16.0% (140/876). The treatment specific incidence was 11.2% (49/438) and 20.8% (91/438) for the vaccinated and the placebo group, respectively. The prevented fraction by vaccination amounted to 0.46 (95% CI: 0.26, 0.61), and the cumulative incidence ratio for the vaccinated group was 0.54. The Cox hazard ratio was 0.51(95% CI: 0.37, 0.72), meaning that the force of abortion is reduced twice in the vaccinated group. The results of this study, the first one following this type of design, shows that the killed whole Neospora caninum tachyzoite preparation had a reasonable effect on the abortion rate in Costa Rican dairy cattle.  相似文献   

Systemic acquired resistance delays race shifts to major resistance genes in bell pepper     

Romero AM  Ritchie DF 《Phytopathology》2004,94(12):1376-1382

ABSTRACT The lack of durability of host plant disease resistance is a major problem in disease control. Genotype-specific resistance that involves major resistance (R) genes is especially prone to failure. The compatible (i.e., disease) host-pathogen interaction with systemic acquired resistance (SAR) has been studied extensively, but the incompatible (i.e., resistant) interaction less so. Using the pepper-bacterial spot (causal agent, Xanthomonas axonopodis pv. vesicatoria) pathosystem, we examined the effect of SAR in reducing the occurrence of race-change mutants that defeat R genes in laboratory, greenhouse, and field experiments. Pepper plants carrying one or more R genes were sprayed with the plant defense activator acibenzolar-S-methyl (ASM) and challenged with incompatible strains of the pathogen. In the greenhouse, disease lesions first were observed 3 weeks after inoculation. ASM-treated plants carrying a major R gene had significantly fewer lesions caused by both the incompatible (i.e., hypersensitive) and compatible (i.e., disease) responses than occurred on nonsprayed plants. Bacteria isolated from the disease lesions were confirmed to be race-change mutants. In field experiments, there was a delay in the detection of race-change mutants and a reduction in disease severity. Decreased disease severity was associated with a reduction in the number of race-change mutants and the suppression of disease caused by the race-change mutants. This suggests a possible mechanism related to a decrease in the pathogen population size, which subsequently reduces the number of race-change mutants for the selection pressure of R genes. Thus, inducers of SAR are potentially useful for increasing the durability of genotype-specific resistance conferred by major R genes.  相似文献   

In this issue – May 2010     

AE Jackson 《Australian veterinary journal》2010,88(5):157-159

Flea-associated infectious agents in cats in Eastern Australia · Complications of barium-impregnated polyethylene spheres · Reproductive efficiency of Thoroughbred and Standardbred horses · GPS tracking collars to monitor horses · Correction of vesicovaginal reflux in mares · Antibodies to Lawsonia intracellularis in Australian pig herds · Mucormycosis in the platypus · Panniculitis from Mycobacterium mageritense in a Tasmanian devil  相似文献   

IN THIS ISSUE – June 2010     

AE Jackson 《Australian veterinary journal》2010,88(6):201-203

Surveillance for West Nile virus in Australia: role of the little raven · Fertility in mares after surgical correction of rectovaginal fistula · Development of method for serial blood sampling from conscious dogs · Specificity of a commercial snake venom detection kit in dog and cat urine · Femoral component failure in canine cemented total hip replacement · Hepatic myelolipoma incarcerated in a peritoneopericardial diaphragmatic hernia in a cat · Diclofenac sodium and flunixin meglumine with antibacterial treatment of respiratory disease of calves · Lead-free petrol reduces risk of acute lead poisoning in Australian cattle  相似文献   

In this issue – April 2014     

AE Jackson 《Australian veterinary journal》2014,92(4):89-90

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