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41.
One hundred eighteen dogs were studied at three veterinary teaching hospitals after the administration of midazolam (0.1 mg/kg, intravenously [IV]) or a placebo. Midazolam and placebo treatments were randomized and blinded to the investigators. The dose of thiamylal required for tracheal intubation 3 to 5 minutes after midazolam or placebo was calculated. The dose of thiamylal at the three hospitals was 10.6,9.8, and 10.1 mg/kg IV after midazolam, and 12.1,11.2, and 11.6 mg/kg IV after placebo. Pooled data from the three hospitals yielded a significant (p < .001) decrease in mean IV thiamylal dose after midazolam (10.2 mg/kg) compared with placebo (11.6 mg/kg). Overall, there was a 12% decrease in the dose of thiamylal required for tracheal intubation after midazolam compared to that after the placebo. The thiamylal dose was significantly (p < .001) decreased after midazolam compared with placebo for dogs weighing more than 15 kg but not for dogs weighing less than 15 kg.  相似文献   
42.
The accuracy of diagnoses based on examination of frozen sections was determined by comparing the results to those obtained by examination of tissues prepared using conventional methods (formalin fixation, paraffin-embedded tissue). One hundred ninety-four specimens were examined using the frozen section technique; 37 were examined to confirm a tentative diagnosis or to document lymph node metastasis and the remainder were examined to diagnose an unknown pathologic process. Of the 194 specimens examined, an accurate, specific diagnosis was obtained in 161 (83%); in 19 (10%), the pathologic process was correctly identified, but a specific diagnosis was not obtained; and in 2 (1%) the diagnosis was deferred. The remaining 12 (6%) were incorrectly diagnosed by the frozen section technique. When the number of specimens in which a specific diagnosis was obtained was combined with the number of specimens in which the pathologic process was correctly identified, the overall accuracy rate of the frozen section technique was 93%. There was no difference in the accuracy of the frozen section technique based on the reason for submission of the sample, source of tissue submitted, or the type of pathologic process (i.e., inflammatory or neoplastic). Of the 12 incorrect diagnoses, 4 (33%) were because of sampling errors and 8 (67%) were caused by interpretation errors. The proposed indications for the use of intraoperative frozen sections are: 1) to determine the nature of a pathologic process for which a preoperative diagnosis has not been established, 2) to determine the extent of spread of neoplastic tissue to lymph nodes and other organs, 3) to evaluate resection margins of a neoplastic process, and 4) to clarify situations where a discrepancy exists between the preoperative cytologic or histologic diagnosis and intraoperative gross pathology.  相似文献   
43.
We assessed growth in subyearling chinook salmon (Oncorhynchus tshawytscha) during the 1998 El Niño and 1999 La Niña in the Gulf of the Farallones, a region of the continental shelf off central California seaward of the Golden Gate and the southernmost ocean entry point for the species in North America. Juvenile salmon demonstrated greater growth during this strong El Niño, when water temperature anomalies of more than +3°C were recorded at local buoys, than during the similarly strong 1999 La Niña. Slopes of regressions of weight on length, length on age, and weight on age were all significantly greater for juvenile salmon during the 1998 El Niño compared with those in the 1999 La Niña. Daily otolith increment widths, an estimator of somatic growth, corroborated population data. Between June 1 and August 9, mean increment widths for juvenile chinook salmon in 1998 were 3.54 ± 0.03 μm, significantly larger than the 3.13 ± 0.03 μm found in juveniles during the same time interval in 1999. Condition factor for juvenile chinook salmon entering the ocean at the Golden Gate was the same in both years, but became significantly greater in ocean fish during the 1998 El Niño than in ocean fish during the 1999 La Niña. Energy storage was significantly greater in ocean juvenile salmon during the 1998 El Niño as well. Mean triacylglycerol/cholesterol ratios increased following ocean entry in 1998, whereas they declined in ocean juveniles during 1999. Thus, not only was growth better in the El Niño period compared with La Niña, but lipid accumulation was also better. Oceanographic data for 1998 indicated elevated temperatures, lower salinity, greater freshwater outflow from San Francisco Bay, northerly flowing coastal currents, and positive upwelling index anomalies. This combination of environmental factors resulted in greater zooplankton productivity that, in conjunction with higher temperatures, allowed metabolic processes to enhance growth. Although El Niño events have certainly produced large-scale, and often adverse, effects on ecosystems, the results of this study emphasize the importance of local oceanographic conditions to growth and other physiological and ecological processes.  相似文献   
44.
Abstract This study assessed exploitation and evaluated management options for walleye, Sander vitreus (Mitchill), in Glen Elder Reservoir, Kansas. A total of 2429 walleye varying from 240 to 687 mm was tagged with Carlin dangler tags during 2000–2003. After correcting for tag loss and non‐reporting, exploitation of walleye was estimated as 68.3%. More than 85% of the tagged walleye were harvested during April to June and 75% were harvested within 6 months after tagging. A Beverton‐Holt yield‐per‐recruit model was used to evaluate six minimum length limits varying from 250 to 610 mm. Given current exploitation rates, population demographics and harvest regulations (381‐mm minimum length limit), the walleye population is probably experiencing recruitment overfishing. Model results suggested that a 610‐mm minimum length limit would be required to prevent growth overfishing and a 533‐mm or longer minimum length limit would prevent recruitment overfishing.  相似文献   
45.
Whole plant studies have reaffirmed that of the halides and pseudohalide thiocyanate, only iodide and thiocyanate possess defoliant properties. Established work has indicated their possible involvement with IAA (indole-3-acetic acid). In vitro studies have suggested that IAA destruction is not through a direct interaction between IAA and the halides and pseudohalide but depends on their conversion to the halogen or pseudohalogen which can then destroy IAA. This may be accomplished by the peroxidase enzyme system for iodide only and docs not provide a mechanism for thiocyanate activity. However, both iodide and thiocyanate have chemical oxidation potentials suitable for their conversion to the halogen or pseudohalogen respectively via the photosynthetic apparatus. Hence, this would provide an explanation for then activity and the apparent inactivity of bromide, chloride and Buoride which would be oxidized very slowly or not at all.  相似文献   
46.
The Food Animal Residue Avoidance Databank (FARAD) is a pilot project funded through the USDA Extension Service. It represents a major effort to compile into a single source large amounts of information on veterinary pharmaceutics, pharmacokinetics and physiochemical properties of drugs and other chemicals used in livestock production. FARAD is a computer-based system consisting of five data and numerous command files that access the data files to facilitate rapid input and retrieval of the desired information. The data files include proprietary information on all pharmaceutical products approved for use in food animals in the United States; physicochemical information on more than 100 chemicals contained in the databank; regulatory information pertaining to tolerance and action levels of chemical residues in animal products and allowable concentrations of drugs in feed; pharmacokinetic rate and volume constants pertinent to residue depletion modeling in a variety of species; bibliographic citations to which all of the information contained in the databank is referenced. All of the information in FARAD is currently available through three regional access centers in the United States, and direct computer access to the data may become available in the future.  相似文献   
47.
Three 0.01m Fe(ClO4)3 Solutions of R= 0, 1, and 2, respectively, were studied over a period of 8 months, where R is referred to the HCO3?/Fe3+ mole ratio in preparation. The R= 0 solution was initially light yellow and clear but rapidly changed to a dense cloudy Suspension after a 9-day induction period. Hydrolysed species rapidly grew from <10 nm to >650 nm. Particles of intermediate size were not observed during the entire period of study. Settleable FeOOH precipi-tate was first observed in 5 weeks with 23 per cent of its iron noted as precipitate at the end of 5 months. The R= 1 and R= 2 Solutions were reddish-brown of low turbidity. Rapid hydrolysis and polymerization were observed immediately after preparation. The hydrolysed species gradually grew in size during ageing and no settleable FeOOH precipitate was observed for at least two years. A hypo-thesis based on Lamb and Jacques's model of Fe3+ hydrolysis is proposed to interpret the reactions taking place in these three Solutions. In the R= 0 solution, the initial number of nuclei for condensation is low, whereas the poten-tial supply of Fe(OH)3 is abundant. In the R= 1 and R= 2 Solutions the number of nuclei initially formed is high, whereas a limited amount of mono-meric Fe(OH)3 is available for condensation. The initial number of nuclei relative to the concentration of monomeric species is the key factor that governs the appearance and properties of these Solutions.  相似文献   
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49.
Abstract The experimental hypothesis testéd was that dogs with generalized demodicosis have significantly lower levels of interleukin-2 (IL-2) production and IL-2 receptor expression as compared with normal dogs. The specific objective of this study was to compare the production of IL-2 and IL-2 receptor expression of peripheral blood mononuclear cells in normal dogs and dogs with generalized demodicosis. Ten dogs with juvenile-onset generalized demodicosis were evaluated. Dogs with generalized demodicosis had a significantly lower in vitro lymphocyte blastogenesis response (P < 0.006), fewer cells expressing IL-2 receptors (P < 0.03), and decreased IL-2 production (P < 0.01) than control dogs. Resumen La hipótesis experimental fue que los perros con demodicosis generalizada tienen niveles significativamente inferiores de producción y expresión de receptores de interleuquina-2 (IL-2) comparado con perros normales. El objetivo especifico de este estudio fue el de comparar le producción y expresión de receptores de IL-2 en células mononucleares de sangre periférica en perros normales y en perros con demodicosis generalizada. Se evaluaron diez perros con demodicosis generalizada iniciada en edad temprana. Los perros con demodicosis generalizada tenian in vitro una respuesta blastogénica linfocitaria inferior (P < 0.006), menos células con expresión de receptores de IL-2 (P < 0.03) y una disminución en la producción de IL-2 (p<0.01) respecto a los perros control. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluación de la producción y expresión de recepetores de interleuquina-2 en perros con demodicosis generalizada.) Veterinary Dermatology 1996; 7 : 213–219.] Résumé L'hypothèse expérimentale est que les chiens à démodécie généralisée présente une diminution significative du taux d'interleukine 2 (IL-2) et de l'expression des récepteurs de l'interleukine 2 comparativement à des chiens sains. L'objectif de cette étude est de comparer la production d'I12 et l'expression des récepteurs de l'IL-2 par des lymphocytes sanguins périphériques de chiens témoins et de chiens atteints de démodécie généralisée. Dix chiens avec une démodécie généralisée juvenile ont été testés. Les chiens à démodécie généralisée présentent une transformation lymphoblastique plus basse (p< 0.006), moins de cellules exprimant les récepteurs IL-2 (p<0.03) et une diminution de la production d'IL-2 (p<0.01) par rapport aux chiens témoins. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis. (Evaluation de la production d'interleukine 2 et de l'expression des récepteurs de l'interleukine 2 chez des chiens à démodécie généralisée.) Veterinary Dermatology 1996; 7 : 213–219.] Zusammenfassung Es wurde die experimentelle Hypothese getestét, daß Hunde mit generalisierter Demodikose über signifikant niedrigere Spiegel an Interieukin2-(IL-2)Produktion und IL-2-Rezeptorexpression verfügen im Vergleich zu gesunden Hunden. Der wesentilche Gegenstand dieser Untersuchung war, die Produktion von IL-2 und die IL-2Rezeptorexpression in den mononukleären Zellen des peripheren Blutes bei gesunden Hunden und solchen mit generalisierter Demodikose zu vergleichen. Zehn Hunde mit juvenilem Beginn von generalisierter Demodikose wurden untersucht. Hunde mit generalisierter Demodikose hatten eine signifikant niedrigere in vitro-Reaktion der Lymphozytenblasogenese (P < 0, 006), weniger Zellen, die IL-2Rezeptoren zeigten (P < 0,03) und eine verminderte IL-2Produktion (P < 0,01) als die Kontrollhunde. [Lemarie, S.L., Horohov, D.W. Evaluation of interleukin-2 production and interleukin-2 receptor expression in dogs with generalized demodicosis (Untersuchungen über die Interleukin2-Produktion und Interleukin2-Rezeptorexpression bei Hunden mit generalisierter Demodikose) Veterinary Dermatology 1996; 7 : 213–219.]  相似文献   
50.
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