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21.
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Anesthetic potency of nitrous oxide in young swine (Sus scrofa) 总被引:1,自引:0,他引:1
Determination of nitrous oxide (N2O) potency was accomplished by extrapolation using the concepts of minimum alveolar concentration (MAC) and additivity among inhalation anesthetics. Halothane and isoflurane anesthetic requirement (alveolar concentration) necessary to achieve MAC in 9 pigs decreased with each successive increase in the percentage of inspired N2O (25%, 50%, 75%). Halothane and isoflurane MAC was determined to be 0.94 +/- 0.03 and 1.75 +/- 0.01 volumes percent, respectively. Halothane and isoflurane requirements decreased to 0.74 +/- 0.02, 0.66 +/- 0.02, and 0.58 +/- 0.02; and to 1.56 +/- 0.02, 1.38 +/- 0.02, and 1.08 +/- 0.03 volumes percent with 25%, 50%, and 75% N2O, respectively. The line of best fit derived from regression analysis of the combined data (isoflurane and halothane MAC values) had a correlation coefficient of 0.987 and an X intercept equivalent to 195% N2O. The potency of N2O in pigs was similar to that of other domesticated mammals and reduced halothane and isoflurane anesthetic requirements by approximately 50% of the reduction observed in human beings. 相似文献
23.
DJ STEWART JA VAUGHAN TC ELLEMAN† PA HOYNE† KJ BURNS JH DUFTY 《Australian veterinary journal》1991,68(2):50-53
The relationship between the serological classification system for serogroup B and for serogroup H of Bacteroides nodosus and cross-protection between subgroups within these serogroups was examined. Protection against ovine footrot following vaccination was achieved against other subgroup strains provided sufficient cross-reactive antibody was induced by shared pilus antigens. Within serogroup B, better cross-protection against one subgroup was obtained with a pili vaccine than a whole cell vaccine which correlated with higher pilus antibody titres induced by the former. For serogroup H, a lack of cross-protection and serological reactivity between subgroups was demonstrated, which indicates that the prototype strain of subgroup H2 should be designated a new serogroup. 相似文献
24.
Intravenous anesthesia 总被引:2,自引:0,他引:2
Anticholinergics, tranquilizers, and sedative-hypnotics are the usual agents used for preanesthetic sedation of the horse. Of these drugs, the anticholinergics are of little importance in the horse. Acepromazine is the most useful and widely used tranquilizer, whereas xylazine is a safe and popular sedative. A newer sedative recently made available to the veterinarian for clinical use in horses is detomidine. Thiobarbiturates are seldom used alone any longer but are still useful when combined with guaifenesin for induction and maintenance of anesthesia. Other, more contemporary drug combinations that have largely replaced thiobarbiturates and chloral hydrate include xylazine with ketamine, xylazine with Telazol, detomidine with Telazol, and guaifenesin with ketamine and xylazine. 相似文献
25.
Samples of pleural fluid from 20 horses with effusive pleural diseases of various causes were evaluated; samples from 19 horses were used for the study. There were differences for pH (P = 0.001) and partial pressure of oxygen (PO2) between arterial blood and nonseptic pleural fluid (P = 0.0491), but there were no differences for pH, PO2, partial pressure of carbon dioxide (PCO2), and concentrations of bicarbonate (HCO3-), lactate, and glucose between venous blood and nonseptic pleural fluid. Paired comparisons of venous blood and nonseptic pleural fluid from the same horse indicated no differences. There were differences (P = 0.0001, each) for pH, PO2, PCO2, and concentrations of HCO3- between arterial blood and septic pleural fluid. Differences also existed for pH (P = 0.0001), PCO2 (P = 0.0003), and concentrations of HCO3- (P = 0.0001), lactate (P = 0.0051), and glucose (P = 0.0001) between venous blood and septic pleural fluid. Difference was not found for values of PO2 between venous blood and septic pleural fluid, although 4 samples of septic pleural fluid contained virtually no oxygen. Paired comparisons of venous blood and septic pleural fluid from the same horse revealed differences (P less than 0.05) for all values, except those for PO2. These alterations suggested functional and physical compartmentalization that separated septic and healthy tissue. Compartmentalization and microenvironmental factors at the site of infection should be considered when developing therapeutic strategies for horses with septic pleural disease. 相似文献
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S Patton P T Chandler E B Kalan A R Loeblich G Fuller A A Benson 《Science (New York, N.Y.)》1967,158(802):789-790
Two harvests of ocean-growing red tide, comprised mainly of Gonyaulax polyedra, were evaluated in limited trials of rat feeding. The protein of red tide (25 to 30 percent, dry basis) supported growth satisfactorily. The essential amino acid composition of the protein closely resembles that of casein, the major protein of milk. As a marine resource, plankton represents a challenge for research. 相似文献
29.
Benson DE Conrad DW de Lorimier RM Trammell SA Hellinga HW 《Science (New York, N.Y.)》2001,293(5535):1641-1644
We report a flexible strategy for transducing ligand-binding events into electrochemical responses for a wide variety of proteins. The method exploits ligand-mediated hinge-bending motions, intrinsic to the bacterial periplasmic binding protein superfamily, to establish allosterically controlled interactions between electrode surfaces and redox-active, Ru(II)-labeled proteins. This approach allows the development of protein-based bioelectronic interfaces that respond to a diverse set of analytes. Families of these interfaces can be generated either by exploiting natural binding diversity within the superfamily or by reengineering the specificity of individual proteins. These proteins may have numerous medical, environmental, and defense applications. 相似文献
30.
Löw K Crestani F Keist R Benke D Brünig I Benson JA Fritschy JM Rülicke T Bluethmann H Möhler H Rudolph U 《Science (New York, N.Y.)》2000,290(5489):131-134
Benzodiazepine tranquilizers are used in the treatment of anxiety disorders. To identify the molecular and neuronal target mediating the anxiolytic action of benzodiazepines, we generated and analyzed two mouse lines in which the alpha2 or alpha3 GABAA (gamma-aminobutyric acid type A) receptors, respectively, were rendered insensitive to diazepam by a knock-in point mutation. The anxiolytic action of diazepam was absent in mice with the alpha2(H101R) point mutation but present in mice with the alpha3(H126R) point mutation. These findings indicate that the anxiolytic effect of benzodiazepine drugs is mediated by alpha2 GABAA receptors, which are largely expressed in the limbic system, but not by alpha3 GABAA receptors, which predominate in the reticular activating system. 相似文献