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31.
Serial physiological responses were examined for 150 min from captive collared peccaries during immobilization with ketamine hydrochloride. Rectal temperatures decreased significantly (P less than 0.01) during anesthesia. Serum concentrations of total proteins, albumin, cholesterol, alanine aminotransferase, and calcium declined significantly (P less than 0.05) during the first 45 min post-immobilization before stabilizing. Concentrations of lactate dehydrogenase and alkaline phosphatase in sera showed similar but nonsignificant (P greater than 0.05) trends. Inorganic phosphorus and aspartate aminotransferase concentrations increased significantly (P less than 0.05) throughout the trial. Concentrations of serum glucose and glucocorticoid during the immobilization period were highly variable between individuals. Serum electrolytes, urea nitrogen, creatinine, gammaglutamyl transferase and progesterone were not significantly (P greater than 0.05) affected by immobilization. Elevations in serum testosterone were noted. Results indicated appropriate sampling times relative to immobilization for assay of particular serum biochemicals and steroid hormones during investigations of the physiology of the collared peccary. 相似文献
32.
A sequential study of electrolyte leakage from roots inoculated with Phytophthora cinnamomi demonstrated changes in leakage in response to infection. These changes may be characterised in terms of susceptibility and resistance. Field resistant species showed two types of response (i) rapid leakage 2—4 h after inoculation, such as in Eucalyptus calophylla, E. maculata and Gahnia radula, (ii) no significant increase in leakage with infection, for example in cereals and in juncus bufonius. Susceptible species, such as Xanthorrhoea australis, E. sieberi and E. marginata showed slow but continually increasing leakage after inoculation, and usually lost significantly more electrolyte than field resistant species. Both electrolyte leakage and susceptibility of two Eucalyptus species varied with root temperature. Roots of both the susceptible and field resistant Eucalyptus species grown at 14°C showed similar leakage patterns to those grown at 24°C although no lesions formed at 14°C. Both amount of leakage and lesion length increased at 28°C. E. marginata (susceptible) lost significantly greater quantities of electrolyte than E. calophylla at each temperature tested. Leakage from artificially wounded roots did not vary with either temperature or with host susceptibility. No significant changes in conductivity were recorded with saprophytic colonization of roots, or with incubation in either low molecular weight culture filtrate or β-glucan solutions. Vacuum infiltration with the culture filtrate or the β-glucan slightly increased initial electrolyte loss in comparison with that of the controls. The increased leakage from infected roots may be toxin mediated or due to enzymie degradation of host plasma membranes, and occurred within the region of the limited lesion in the case of field resistant species, compared with the larger zone of extending necrosis characteristic of susceptible species. 相似文献
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Humoral and cellular cytotoxic immune mechanisms of cats were compared against feline leukemia virus (FeLV)- and feline sarcoma virus (FeSV)-transformed cells. The groups of animals studied were nonexposed control cats; FeLV-infected immune or viremic tumor-bearing cats; FeSV-inoculated tumor progressor or regressor cats, and cats immunized with FeSV-transformed autochthonous fibroblasts (ATF). Sera containing complement-dependent antibodies (CDA), which lysed FeLV-producer lymphoma lines, had no cytotoxic effects when tested against FeLV-producer FeSV-transformed fibroblasts. Sera with lytic CDA activity were also tested for antibody-dependent cellular cytotoxic (ADCC) effects with peripheral blood lymphocytes (PBL) from nonimmune cats. No ADCC activity was detected against either lymphoid or fibroblast target lines. To demonstrate that cat PBL contained ADCC effector cells, antibody-coated murine target cells were employed and positive results obtained. Natural killer (NK) assays were performed using PBL from normal and tumor-bearing cats. Cytotoxic effects were only detectable to FeLV-producer lymphomas, and comparable levels of NK activity were found in normal and lymphoid tumor-bearing animals. In cats immunized with ATF, a population of effector cells was found in peripheral blood which had functional characteristics of cytotoxic T lymphocytes (CTL). The killing of ATF by CTL-like cells was not inhibited by FeLV/FeSV immune sera or by sera from autochthonous immune cats. The comparative importance of humoral and cellular cytotoxic mechanisms against FeLV- and FeSV-induced tumors is discussed. 相似文献
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D Sarantakis W A McKinley N H Grant 《Biochemical and biophysical research communications》1973,55(2):538-542
The tetradecapeptide H-Ala-Gly-Ala-Lys-Asn-Phe-Phe-Trp-Lys-Thr-Phe-Thr-Ser-Ala-OH (Ala3, 14-somatostatin) an analog of the somatotropin release inhibiting factor (somatostatin SRIF) was synthesized by solid phase peptide methods. It shows somatotropin release inhibiting activity at 5 μg/ml concentration. 相似文献
38.
Mössbauer effect measurements show that the ferrous ions in dehydrated deoxymyoglobin are in the high spin state while those in dehydrated deoxyhemoglobin (AHb) are equally distributed between high and low spin states. It is concluded that the two spin states present in AHb are associated with the iron site difference of the α- and β-chains. 相似文献
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Simple, rapid spectrophotofluorometric methods were developed for determining each constitutent in the mixtures of catechol and protocatechuic acid and in mixtures of quinol and gentisic acid. A colorimetric method involving the use of 4-aminoantipyrine and extraction with chloroform was proposed for determining each constituent in mixtures of phenol and p-hydroxybenzoic acid. Two simple and rapid colorimetric methods were used in conjunction to determine each constituent in mixtures of pyrogallol and gallic acid. The accuracy of all methods was within ±5%. 相似文献
40.
Exopolysaccharide Colanic Acid and Its Occurrence in the Enterobacteriaceae 总被引:13,自引:8,他引:5 下载免费PDF全文
A study of strains from the genera Salmonella, Escherichia, and Aerobacter has shown that under appropriate conditions many strains produce an exopolysaccharide slime of identical composition, which has been identified as colanic acid on the basis of its chemical composition and its sensitivity to certain bacteriophage-induced depolymerase enzymes. Chemical analysis shows that the polysaccharide contains O-acetyl groups in addition to the sugars glucose, galactose, fucose, and glucuronic acid. Mild acid hydrolysis has led to the isolation of a β-glucosylfucose in addition to glucuronic acid containing oligosaccharides. Many strains were found to synthesize colanic acid under normal conditions of growth or under conditions favoring polysaccharide synthesis, whereas others only synthesized colanic acid when the control mechanism was derepressed by p-fluorophenylalanine. 相似文献