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The toxicities of five systemic fungicides [benomyl, carbendazim, methyl 4-(2- aminophenyl)-3-thioallophanate (NF48), thiabendazole and thiophanate-methyl] and of two non-systemic fungicides (guazatine and phenylmercury acetate) against Fusarium culmorum were compared on agar plates; their performance as seed treatments was measured by inoculating the shoot bases of wheat seedlings with F. culmorum in pot experiments. The two most effective compounds, benomyl and thiabendazole, and the less effective thiophanate-methyl, were evaluated in further seed treatment experiments in which leaf sheaths and roots of slightly older plants were infected. The three fungicides protected the first leaf sheath for more than 5 weeks, but thiophanate-methyl was least effective. Against root disease, they were effective when infection was mild, but only thiabendazole significantly controlled severe infection. Bioautography confirmed that fungicide levels in shoots were greater after benomyl and thiabendazole, than after carbendazim and thiophanate-methyl treatments, and that concentrations of fungicide after benomyl, carbendazim and thiophanate-methyl treatments generally declined between 5-13 weeks after treatment. Thiabendazole produced a second fungitoxic component detectable in plants after 34 days.  相似文献   
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Recent technologic advances have allowed the production and marketing of cage-side blood gas analyzers to private practitioners. The widespread use of cage-side portable blood gas analyzers in veterinary practices has increased the need to develop the basic skills of blood gas analysis as part of a tool kit for practicing veterinarians. Rapid expansion of emergency and critical care medicine as a specialty and increased numbers of veterinary emergency and veterinary specialty practices have occurred concurrently with the availability of blood gas analyzers that are affordable for private practitioners. As a result, evaluation of blood gas results is no longer an activity confined to academic institutions and has become a daily part of many practicing veterinarians' activities.  相似文献   
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Fossil cephalopods are frequently encrusted by epibionts; however, determining whether encrustation occurred prior to or post‐mortem to the host, and whether the final environment of deposition corresponds to the habitat of encrustation is complex. The present paper describes cirripede epibionts, their calcareous bases and their attachment scars on 6 post‐mortem shells of Nautilus macromphalus, collected from deep water off New Caledonia. The cirripedes have left both cemented calcareous bases of Hexelasma and scars associated with bioerosion and discoloration produced by verrucomorph barnacles. Live cirripedes included a Metaverruca recta, with articulated opercular plates and organic tissue (on a shell that had been exposed on the sea floor for at least 150 years), and specimens of Hexelasma velutinum, one of which was partly attached to an internal surface of a shell. The disposition of verrucomorphs indicates that most Nautilus shells were colonized post‐mortem rather than during a floating stage. However, as cirripedes are known to have colonized living Nautilus, some Hexelasma, preserved only as calcareous eroded bases, may represent specimens that settled on a living Nautilus. The degree of bioerosion and discoloration induced by verrucomorph barnacles varies according to the surface preservation of Nautilus shells, with deeper and discolored traces preserved on old and degraded shells. Traces made by verrucomorphs described here are ellipsoidal and a new ichnotaxon, Anellusichnus ellipticus, is proposed to accommodate them. Importantly, verrucomorphs and other cirripede taxa with membranous bases that were attached to pristine shells may not leave any substantial scars, and, thus, will be difficult to detect in the fossil record.  相似文献   
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Objective

To compare the efficacy and quality of analgesia provided by constant rate infusions (CRIs) of hydromorphone and fentanyl in dogs in the intensive care unit (ICU).

Study design

Prospective, randomized, blinded, clinical trial.

Animals

A total of 29 client-owned dogs.

Methods

Dogs prescribed a μ-opioid agonist infusion for postsurgical or medical pain were randomized to be administered either hydromorphone (0.025 or 0.05 mg kg?1 bolus, followed by a 0.03 mg kg?1 hour?1 infusion) or fentanyl (2.5 or 5 μg kg?1 bolus, followed by a 3 μg kg?1 hour?1 infusion). The technical staff and clinicians were blinded as to which drug was administered. Pain scores, using the Colorado State University Canine Acute Pain Scale, sedation scores and nausea scores were assigned at regular intervals and compared between groups. Dose escalation and de-escalation of the study drug were performed according to set protocols. Adverse clinical signs and all other medications administered were recorded and compared between groups. The study drug was discontinued if the animal remained painful despite dose escalations, or if adverse effects were noted.

Results

The pain scores were of low magnitude and were not significantly different between groups. The use of concurrent analgesia, sedation/anxiolytic medications and antacid/antiemetic medications was not different between groups. Sedation and nausea scores were not statistically different between groups.

Conclusions and clinical relevance

Hydromorphone and fentanyl CRIs appear to be equally effective for adequate pain relief in dogs, with no significant differences in adverse effects. Therefore, either drug may be chosen for control of postsurgical or medical pain in an ICU setting.  相似文献   
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Conidia of the fungus Metarhizium flavoviride were formulated in a paraffinic oil, ‘Shellsol’ T, and sprayed using the Francome MkII exhaust nozzle sprayer. Germination of the conidia collected from the spray was reduced by 30% as compared to unsprayed conidia. However, in bioassays, there was no detectable difference in virulence with conidia collected from the spray samples and unsprayed formulation. This indicated that, despite the recorded reduction in the concentration of active conidia, the efficacy of the formulation remained unchanged after passing through the exhaust nozzle sprayer. The droplet size spectra produced by the sprayer were investigated using the Malvern series 2600cc particle size analyser. The optimum droplets for locust control produced by this sprayer were generated by the number 1 nozzle (internal diameter 2·5 mm) with the number 1 restrictor ring (internal diameter 12.5 mm) sprayed at a pressure of 0·2 bar. The droplets thus produced had a volume median diameter of 58 μm when the nozzle protruded between 1 and 2 mm above the level of the restrictor ring. Of the droplets in the spray plume created by these conditions, 33% were between 50 and 100 μm, a range recommended as an achievable optimum for the ultra-low-volume application of Metarhizium flavoviride. The role of the exhaust nozzle sprayer as a tool for the application of M. flavoviride for locust control is discussed with reference to other vehicle-mounted ultra-low-volume sprayers. © 1997 SCI  相似文献   
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