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71.
M-mode and Doppler echocardiographic values were obtained from 30 normal adult ferrets (14 neutered females, 13 neutered males, 3 intact males) sedated with an intramuscular combination of ketamine hydrochloride and midazolam. Routine M-mode measurements of the left and right ventricle, left atrium (LA) and aorta (AO) and Doppler measurements of aortic and pulmonic outflow, and mitral inflow were recorded. The following values were calculated: LA:AO diameter, ratio of peak E: peak A wave velocity (E:A ratio) for mitral inflow, and stroke volume (SV), cardiac output (CO) and cardiac index (CI) for both pulmonary and aortic outflow tracts. Maximal aortic velocities (AOmax) and velocity-time integral values (AO VTI) were significantly less than corresponding pulmonary outflow tract values (PAmax, PA VTI) but there was no difference in calculated values for SV, CO or CI. Calculated CO values were in the range expected based on the size of the species. Difficulties in aligning the aortic outflow tract for Doppler imaging may make pulmonary outflow Doppler values more consistent for use in estimating volume flow in ferrets.  相似文献   
72.
73.
Results of bacteriologic culture of specimens obtained from 14 horses with pneumonia and from 15 horses that were clinically healthy (nonpneumonia group) were compared. Specimens were obtained by use of an endoscopic guarded tracheal swabbing method and percutaneous tracheal aspiration. The percentage of agreement between the 2 tracheal specimens for the horses of the pneumonia group was 79% for aerobic isolates and 100% for anaerobic isolates. The percentage of agreement between results of the 2 tracheal specimens for horses of the nonpneumonia group was 80% for aerobic organisms and 93% for anaerobic organisms. The endoscopic guarded swabbing method described here for obtaining specimens from the lower airways for bacteriologic culture did not always prevent contamination. Results of the study suggested that this endoscopic swabbing technique has merit and should be considered as an alternative to the tracheal aspiration method. Pseudomonas sp and any anaerobic bacteria that are isolated must be viewed as potential contaminants of the endoscopic swab specimen and may not be involved in the primary pulmonary disease.  相似文献   
74.
Pharmacokinetic variables of etomidate were determined after IV administration of etomidate (3.0 mg/kg of body weight). Blood samples were collected for 6 hours. Disposition of this carboxylated imidazole best conformed to a 2- (n = 2) and a 3- compartment (n = 4) open pharmacokinetic model. The pharmacokinetic values were calculated for the overall best-fitted model, characterized as a mixed 2- and 3-compartmental model. The first and most rapid distribution half-life was 0.05 hour and a second distribution half-life was 0.35 hour. Elimination half-life was 2.89 hours, apparent volume of distribution was 11.87 +/- 4.64 L/kg, apparent volume of distribution at steady state was 4.88 +/- 2.25 L/kg, apparent volume of the central compartment was 1.17 +/- 0.70 L/kg, and total clearance was 2.47 +/- 0.78 L/kg/h.  相似文献   
75.
The antibiograms of 408 Salmonella species isolated from large animals were collected during a three year study from 1981 through 1983. The predominant Salmonella serogroup among these isolates was group B. A consistently high percentage of all isolates were resistant to ampicillin and tetracycline. A pattern of increasing resistance to chloramphenicol and gentamicin was documented for serogroup B isolates while the susceptibility of the isolates to neomycin increased. There was a decrease in the incidence of susceptibility to sulfamethoxazole-trimethoprim among the group E isolates. These changes were not as remarkable, nor as alarming, as the overall decreased susceptibility to chloramphenicol and gentamicin. An evaluation of the principles concerning use of antimicrobial agents in veterinary medicine for treatment of Salmonella infections is recommended.  相似文献   
76.
The Southern Pine Beetle (SPB) is a major pest in southern U.S.A., Mexico, and Central America. Enormous resources in terms of funding, personnel, and effort have been allocated for research and development of pest management tools for this pest over the past century. Access to information from journal articles, reports, fact sheets, etc. does require some effort and is often incomplete and difficult to obtain. The emergence of the Internet now allows rapid access to information from diverse sources. We have created a comprehensive website entitled, 'The Southern Pine Beetle Internet Control Center' (SPBICC) (www.spbicc.vt.edu). The goal of the site is to provide all available resources on SPB to anyone with access to the Internet. It is also designed to increase communication among researchers and professionals to help advance the management of this pest. The site is interactive, which permits constant updating without contacting a webmaster. Attributes of the site include background information in the form of fact sheets, reviews, and government handbooks; an interactive diagnostic identification key for SPB and other bark beetles; a searchable expertise directory; a calendar of SPB-related events; a discussion forum; an online SPB spot growth predictive model; a searchable bibliographic database; a webcrawler designed to search for SPB-related websites, and more. Web-based tools were developed to integrate relational databases as the functional base of this site. The dynamic nature of the SPBICC makes it a powerful tool and a model for development of websites for other major agricultural or forest pests.  相似文献   
77.
A pentachlorophenol (PCP) wood treatment plant was studied to determine PCP exposure to people by occupation and to the plant by work area. This plant operates on a year-round basis with a 25 percent increase in production from May through October. Approximately 2.5 million board feet of timber are processed annually. Samples were taken in the morning of the second work week of each month for 5 consecutive months. Samples consisted of serum and urine from the employees and air from locations throughout the plant work area. All samples were analyzed for PCP residue. Peripheral blood was used to culture cells to investigate possible chromosomal aberrations.  相似文献   
78.
The proportion of weed beet and bolting beet in sugar beet crops is increasing, and as much as 24% of beet acreage may now be badly infested. Mechanical and chemical methods of control are being developed, but neither is completely satisfactory. The use of electricity has recently been suggested as a means of control and is investigated in this paper. It is found that high voltages around 5 kV rms can physically destroy annual beet in pots in under 20 sec. Maximum currents vary according to the plant size and range from 0·5 to I A rms for bolters 1-1·4 m high. It is not necessary to completely burn the plant in two to kill it and various ways of minimizing the treatment for speed and energy economy are suggested. Field trials using hand-held electrodes to apply the electric currents to annual beet growing amongst a crop showed that much larger powers (up to 20 kW) were necessary to kill the plants. A tractor-driven system was constructed producing 8kV rms which enabled it to cover 6 rows and travel at speeds up to 16 km/h and it removed 75% of the bolting and weed beet. La lutte électro-thermique contre les betteraves sauvages el les montées dans les betteraves sucrières. La proportion des ressemis et des montées dans les cultures de betteraves à sucre est en augmentation et jusqu'à 14%, des surfaces cultivées en betteraves peuvent maintenant être fortement infestées. Des procédés mécaniques et chimiques de lutte ont été proposés, mais aucun n'est pleinement satisfaisant. L'emploi de l'électricité a été récemment suggéré comme moyen de lutte el il est examiné dans cette publication. II a été constaté que des voltages élevés. autour de 5 k Veff. peuvent détruire physiquenient des betteraves de I'année. cultivées en pots, en moins de 20 sec. Les courant maximaux varient selon la talle de la plante et s'échelonnent entre 0,5 et 1 Aeff, pour des plantes montées de I m à 1,40m de haut.II n'est pas nécessaire de brûler complètement la planie pour la tuer et divers procédés économisant sur la vitesse et l'énergie sont suggérés pour alléger le traitement. Des essais du champ utilisant des électrodes manipulées à la main, pour appliquer les courants électriques aux betteraves annuelles poussant dans une culture, ont montré que des puissances élevées (jusqu'à 20 kW) étaient nécessaires pour tuer les plantes. Un dispositif tiré par un tracteur a été construit produisant 8K Veff lequel permet decouvrir 6 rangs et travaille à des vitesses atteignant 1.6 km/h; il élimine 75%, des montées et des betteraves sauvages. Elekrothermische Bekämpfung von Unkrautrüben und Zukerrübenschossern Der Anteil von Unkraut- und Schossrüben in Zuckerrüben ist ansteigend und derzeit sind 14% der Rübenfläche damit stark verseucht. Zu ihrer Bekämpfung werden mechanische und chemische Verfahren entwickelt, aber keines ist befriedigend. In dieser Arbeit wird über Untersuchungen zur neuerdings vorgeschlagenen Anwendung von Elektrizität berichtet. Unter hohen Spannungen von durchschnittlich 5 kV werden annuelle Rüben, die zu diesem Zweck in Gefässen kultiviert wurden, in weniger als 20 Sekunden zerstört. Die maximalen Stromstärken bewegen sich hierbei. Abhängig von der Pflanzengrösse, zwischen durchschnittlich 0.5 bis I A. wenn die Schossrüben 1 bis 1,4 m hoch sind. Um die Pflanze abzutöten ist es nicht nötig, sie völlig zu verbrennen. Es werden verschiedene Vorschläge zur Reduktion des Aufwandes bezüglich Fahrgeschwindigkeit und Energie gemacht. In Feldversuchen, in denen mit manuell bedienten Elektroden annuelle Rüben in einer Kultur behandelt wurden, zeigte sich, dass weit höhere Leistungen (bis zu 20 kW) notwendig waren, um die Pflanzen zu töten. Es wurde ein traktorbetriebenes Gerät konstruiert. das durchschnittlich 8 kV produziert und mit dem 6 Reihen mit einer Fahrgeschwindigkeit bis zu 1.6 km/Stunde bebandelt werden können. Mit diesem Gerät konnten 75%, der Schossrüben und Unkrautrüben beseitigt warden.  相似文献   
79.
Catch-and-release (C&R) angling is a powerful tool for reducing impacts on recreationally targeted fishes. Although C&R can be mandated in fisheries through regulation, voluntary adoption and informal management are often critical due to minimal enforcement opportunities. Anglers themselves may play a role in increasing C&R adoption through interpersonal sanctioning (i.e., self-policing). To date, little research has examined factors that predict the willingness of anglers to sanction others’ behavior. We present results from surveys (n = 49) with anglers in Argentina to explore their motivations to sanction other anglers within their stakeholder community. Anglers with the strongest intentions to sanction were younger and more open to adopting best practices, identified fishing as important to their lifestyle, and expressed high environmental concern relative to other anglers. Our findings highlight the role that recreational anglers can play in promoting best practices via interpersonal sanctioning and identify barriers that inhibit this type of action.  相似文献   
80.
We have found that applications of sugar-conjugated plant growth regulators (SPGRs) by exposures of roots or shoots to millimolar (mM) SPGRs are key to their uptake and transport for enhancement of vegetative productivity of the entire plant as compared to control populations. Initial surveys utilizing foliar applications of identically nutrient-supplemented 0.3 mM cytokinin glycosides, N6-benzyladenine glycosides, kinetin glycosides; and a 0.3 mM auxin glycoside, indoxyl-β-D-glucopyranoside (IG) resulted in significant shoot enhancements over controls. Foliar application of 0.3 mM kinetin glucoside resulted in significant root increase above the control. Foliar application of 3 mM to 6 mM IG resulted in enhanced root and shoot growths over controls. Similarly, increases of root and shoot yields over controls were observed as a result of foliar application of 3 mM indoxyl-β-D-glucuronide. Foliar application of 1 mM trans-zeatin-β-D-glucoside was particularly effective, resulting in significant enhancement of root and shoot growth with no phytotoxicity.  相似文献   
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