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The oestrogen levels were assessed in 180 urine samples taken from 20 cows. The animals had received over 15 days 40 mg one-per-cent oily solution of chloromadinone acetate. The solution had been applied orally or by pour-on methods. The curves of oestrogen excretion were identical for both methods of application, both during and after completed administration. In other words, the effect obtainable from pour-on application is just as good as that obtainable from oral administration.  相似文献   
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Classical biological control remains the only tool available for permanent ecological and economic management of invasive alien species that flourish through absence of their co‐evolved natural enemies. As such, this approach is recognized as a key tool for alien species management by the Convention on Biological Diversity (CBD), the European and Mediterranean Plant Protection Organization (EPPO) and the European Strategy on Invasive Alien Species (ESIAS). Successful classical biological control programmes abound around the world, despite disproportionate attention being given to occasional and predictable non‐target impacts. Despite more than 130 case histories in Europe against insect pests, no exotic classical biological control agent has been released in the EU against an alien invasive weed. This dearth has occurred in the face of increasing numbers of exotic invasive plants being imported and taking over National Parks, forests and amenity areas in this region, as well as a global increase in the use of classical biological control around the world. This paper reviews potential European weed targets for classical biological control from ecological and socioeconomic perspectives using the criteria of historical biological control success, taxonomic isolation from European native flora, likely availability of biological control agents, invasiveness outside Europe and value to primary industry and horticulture (potential for conflicts of interest). We also review why classical biological control of European exotic plants remains untested, considering problems of funding and public perception. Finally, we consider the regulatory framework that surrounds such biological control activities within constituent countries of the EU to suggest how this approach may be adopted in the future for managing invasive exotic weeds in Europe.  相似文献   
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Objectives To investigate the use of unguided bronchoalveolar lavage techniques in dogs without fibreoptic bronchoscopy, using an adapted single vascular catheter and a double-lumen catheter made from two single vascular catheters.
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 106/L was calculated from 57 clinically and histologically normal dogs. The major residual effects of the technique were localised pulmonary oedema, and alveolar distension with collapse and congestion of distant parenchyma. Thoracic radiographs revealed increased lung opacity for at least up to 7 h after the procedure.
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract.  相似文献   
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In an on‐farm study, 40 weaned piglets aged 3 weeks were vaccinated with Lawsonia intracellularis vaccine orally, IM or IP while a fourth group remained unvaccinated. All vaccinated animals showed increased serum levels of L. intracellularis‐specific IgG antibodies, but significantly elevated concentrations of specific IgG, IgA and cytokines were generated in ileal mucosal secretions from the orally and IP vaccinated pigs when examined at 17 days after vaccination.  相似文献   
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A novel spectrophotometric method for the determination of capsaicinoids in habanero pepper extracts is described that does not require prior analyte separation. The method uses partial-least-squares (PLS-1) multivariate regression modeling techniques in conjunction with ordinary UV absorption spectral data obtained on alcoholic extracts of habanero peppers (Capsicum chinese). The PLS-1 regression models were developed by correlating the known total concentration of the two major capsaicinoids (capsaicin and dihydrocapsaicin) in the extracts as determined by high-performance liquid chromatography with the spectral data. The regression models were subsequently validated with laboratory-prepared test sets. The validation studies revealed that the root-mean-square error of prediction varied from 4 to 8 ppm, based on the results obtained from models prepared from nine test sets. Once a regression model has been developed and validated, analyses of the extracts can be accomplished rapidly by ordinary spectrophotometric procedures without any prior separation steps.  相似文献   
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