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The use of a concentrate emulsion of Melia azedarach green fruits and a suspension of the fungus Beauveria bassiana was evaluated in the control of Rhipicephalus microplus on artificially infested cattle. The evaluation was conducted following the protocol established by the Brazilian Agriculture Ministry. Five groups of 4 or 5 animals were allocated to one of the following treatments: emulsion concentrate of M. azedarach at 0.25% (T AZED 0.25%), emulsion concentrate of M. azedarach at 0.5% (T AZED 0.5%), B. bassiana at 2.4 × 10(8) conidia (T BASS), association of the concentrate of M. azedarach at 0.25% with B. bassiana at 2.4 × 10(8) conidia (T AZED 0.25%+BASS), and control (untreated). The association of the two compounds provided better results than any one isolated treatment, indicating compatibility or perhaps a synergy between M. azedarach and B. bassiana. This treatment resulted in fewer engorged females (129 ± 70) than in the control group (233 ± 82), showing high performance against all developmental stages of the tick. Results revealed an apparent synergistic effect of M. azedarach and B. bassiana in the control of R. microplus that should be further investigated.  相似文献   
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A two-year field experiment (2001 and 2003) was carried out in a Mediterranean environment to study the effects of municipal solid waste (MSW) compost application compared with mineral nitrogen (N) fertilization on the agronomic performance and N utilization of a tomato crop, in rotation with durum wheat. The research was conducted in the south of Italy where five N treatments and two soil tillage depths (40-45 cm and 10-15 cm) were compared. The N treatments were: MSW compost at 140 kg ha?1 (Ncom); mineral N fertilizer at 140 kg ha?1 (Nmin); MSW compost combined with mineral N fertilizer (Nmix) (70 kg ha?1 as organic N plus 70 kg ha?1 as mineral N); mineral N fertilizer at 70 kg ha?1 combined with two applications of foliar fertilizer (Nfito) (3 kg ha?1 as hydrolyzed proteins), and an untreated control (Contr). During cropping cycles, growth parameters and plant N status (SPAD readings and petiole nitrate content) were determined; at harvest the marketable, overripe, green fruit, total yield, yield components, quality performance, total and fruit N uptake, and N efficiency were recorded. In addition, at the beginning and at the end of the two-year experiment, soil chemical characteristics and mineral N was measured, allowing for the calculation of the mineral N deficit in the soil. The results of this research indicate that the application of MSW compost to tomato plants can serve as a N source in Mediterranean conditions, especially when MSW compost is combined with mineral N fertilizer and deeper soil tillage is applied. In fact, deeper soil tillage increased total yield 7.0 t ha?1 compared to surface tillage, whereas soil amended with MSW compost increased total yield compared to the untreated control by approximately 6.4% when used alone and 11.1% when combined with mineral N fertilizer. Nitrogen utilization parameters and Harvest Index varied significantly across years and N treatments. Petiole nitrate content and SPAD readings did not vary between Nmin and Nmix treatments, but they were significantly different from the untreated control. This indicates that plant N status was an effective tool to monitor N supply. After the two-year experiment, the Nmix treatment was statistically not significant in total yield (86.1 and 88.2 t ha?1, respectively), marketable yield (66.9 and 67.7 t ha?1) and quality compared to the Nmin treatment. Furthermore, the Nmix treatment ensured the least N deficit in the soil, indicating that MSW applications were effectively used as alternative organic supplements. Finally, the results indicated a positive effect of MSW application on organic carbon content in the soil and did not show any significant increase of the heavy metals at the end of the two-year experiment.  相似文献   
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OBJECTIVE: To determine the susceptibility of strains of Pasteurella multocida subsp multocida isolated from lung specimens of pigs with pneumonia to 20 antimicrobials and to evaluate the emergence of resistance to those antimicrobials in Spain during the past 2 decades. SAMPLE POPULATION: 63 isolates recovered from 1987 to 1988 and 132 isolates recovered from 2003 to 2004. PROCEDURE: A broth microdilution method was used to determine minimal inhibitory concentration (MIC) range and values for MIC50 and MIC90. Resistance of a strain to an antimicrobial agent was determined by use of the breakpoint value when available. RESULTS: Isolates were generally susceptible to penicillin, ampicillin, ceftiofur, gentamicin, apramycin, neomycin, spectinomycin, chlortetracycline, erythromycin, tilmicosin, enrofloxacin, and florfenicol, and most isolates were resistant to clindamycin, tylosin tartrate, and tiamulin regardless of the time period. A substantial increase in resistance to sulfa-chlorpiridazine, sulfadimethoxine, sulfathiazole, and trimethoprim-sulfamethoxazole was observed, and a minor increase in resistance to oxytetracycline was also detected. Several multiresistance patterns were observed, most frequently among isolates recovered in the 2003 to 2004 interval. CONCLUSIONS AND CLINICAL RELEVANCE: Ceftiofur, florfenicol, and enrofloxacin are recommended for treatment of infections caused by P multocida subsp multocida in Spain. Increased frequency of resistance to oxytetracycline and sulfonamide drugs may be a contraindication for their use.  相似文献   
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Distribution of hyoscyamine and scopolamine in Datura stramonium.   总被引:3,自引:0,他引:3  
The production of hyoscyamine and scopolamine in Datura stramonium has been investigated in the different plant parts, at different stages of their life cycle. Maximum contents were found in the stems and leaves of young plants, hyoscyamine being always the predominant component.  相似文献   
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A comparative study of tannin composition of three species known as barbatim?o (Stryphnodendron adstringens, Stryphnodendron polyphyllum and Dimorphandra mollis) was developed by TLC, hydrolysis followed by PC, and colorimetry. Principal component analysis of the data obtained showed strong differentiation between the genus Dimorphandra and Stryphnodendron. Additionally, barks from the two Stryphnodendron sp. also presented considerable differences in the tannin structure.  相似文献   
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Cabassi  E.  Miduri  F.  Di Lecce  R.  Marin  A.  Ferri  L.  Corradi  A. 《Veterinary research communications》2007,31(1):217-220
Veterinary Research Communications - Cabassi, E., Miduri, F., Di Lecce, R., Marin, A., Ferri, L. and Corradi, A., 2007. Saliva, an alternative biologic matrix to detect glucocorticoid treatment in...  相似文献   
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The Haemophilus parasuis aroA gene encodes 5-enolpyruvylshikimate-3-phosphate synthase and participates in the aromatic amino acids and the folic acid universal metabolic pathway of bacteria. The application of aroA-based PCR-RFLP methodology yields a significant degree of diversity in H. parasuis and Actinobacillus species. PCR amplification of the aroA gene rendered a 1,067-bp fragment in all 15 H. parasuis serovars, and also in Actinobacillus pleuropneumoniae serotypes 1-12, Actinobacillus lignieresii, Actinobacillus equuli, Actinobacillus porcinus, Actinobacillus rossii, Actinobacillus suis, Actinobacillus ureae, Actinobacillus minor and Actinobacillus indolicus. Sau3AI and RsaI digestions of the aroA PCR products rendered seven different restriction fragment length polymorphism (RFLP) patterns: group I (H. parasuis serovars 1, 2, 4-6, and 8-15, A. porcinus and A. ureae), group II (H. parasuis serovars 3 and 7, and A. pleuropneumoniae serotypes 1, 4, 5, 9, 11 and 12), group III (A. lignieresii), group IV (A. pleuropneumoniae serotype 7), group V (A. pleuropneumoniae serotypes 2, 3, 6 and 8, A. equuli, A. rossii, A. minor and A. indolicus), group VI (A. suis) and group VII (A. pleuropneumoniae serotype 10). This is the first report describing the presence of aroA gene in H. parasuis, A. lignieresii, A. porcinus, A. rossii, A. suis, A. ureae, A. minor and A. indolicus and the data presented here demonstrates a significant degree of aroA genetic diversity in H. parasuis and species of the genus Actinobacillus.  相似文献   
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