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SUMMARY An aqueous suspension of air-dried, hammer-milled leaf of Terminalla oblongata (yellow-wood) was administered to sheep by gavage, as a single dose of 5 to 20 g (dry weight)/kg body weight. Doses of 15 g/kg, or more, caused depression, Inappetence, abdominal pain and reduced ruminal movements within 24 to 48 h and some sheep also showed dyspnoea, oplsthotonus and champing of the Jaws. Haematology and blood gas and acid-base measurements were unaffected. In sheep given a dose of 12.5 g/kg, or more, plasma osmolality, aspartate aminotransferase activity and potassium and bilirubin concentrations Increased while plasma total protein markedly decreased and plasma sodium concentration and alkaline phosphatase activity remained normal. Most sheep were necropsled 48 h after dosing. The liver showed zonal hepatocellular necrosis, the pattern of which varied with the dose given. No renal lesions were observed, although one sheep given a very high dose became azotaemic and hyperkalaemic. Hydrothorax, hydroperlcardlum and ascltes developed In sheep given doses of 15 or 20 g/kg.  相似文献   
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OBJECTIVE: To determine whether hematologic and serum biochemical values for blood samples obtained from cats via vascular access ports (VAP) are comparable to those for samples obtained by direct venipuncture. DESIGN: Prospective study. ANIMALS: 14 healthy cats. PROCEDURE: A VAP was surgically implanted in a jugular vein in each cat. Blood samples were obtained from the VAP and by direct venipuncture of the contralateral jugular vein 10 weeks after VAP placement. Results of hematologic and serum biochemical analyses were compared by use of a paired t-test. The Pvalue to reject the null hypothesis was adjusted to account for multiple comparisons by using the Bonferroni procedure in which the nominal P-to-reject value is divided by the number of comparisons (0.05/24 = 0.002). RESULTS: Paired samples (VAP and venipuncture) obtained 10 weeks after VAP placement were evaluated for each cat. Of the 24 measured analytes, only potassium, total protein, and albumin concentrations differed significantly (P< 0.001 for all 3) between VAP and venipuncture samples. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that samples obtained from VAP are suitable for routine hematologic monitoring of feline cancer patients. Sample hemolysis may account for a slight increase in potassium, total protein, and albumin concentrations obtained from VAP samples. However, the values of variables most critical for monitoring of patients receiving chemotherapy (ie, mature neutrophil and platelet counts) are comparable. If proper techniques are used, VAP may be used for administration of chemotherapy as well as for blood collection in cats undergoing cancer treatment.  相似文献   
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The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors.  相似文献   
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Objective To estimate the changes in productivity and profitability in a group of wool-growing farms as they adopted major recommendations from agricultural and veterinary studies.
Farms Four wool-growing farms in south western Victoria were selected from the clients of the Mackinnon Project, a farm consultancy service run from the University of Melbourne. Each farm had closely followed recommended procedures, kept comprehensive financial and physical records and had been clients for at least 5 years. The comparison group was the South Western Victoria Monitor Farm Project (SWVMFP), about 45 farms in the same region as the study farms that were monitored annually by Agriculture Victoria.
Procedure For a 7-year period, the financial and physical performance of both groups of farms was estimated. Stocking rate, wool production, gross farm income, farm operating costs, net farm income and return on assets were compared.
Results Mean gross farm income of the four study farms steadily rose from 86% of the average SWVMFP farm before the adoption of recommendations to an average of 155%. During the same period, net farm income rose from 70% to 207% of the average of the SWVMFP. Return on asset of the four farms rose irregularly from 26% to 145% of the average of the SWVMFP. Farm operating costs on the four farms were higher than for the SWVMFP group, but the ratio of costs remained relatively constant.
Conclusion The adoption of proven research results was associated with large increases in net farm income. An increase in gross income, rather than a reduction in costs was the main reason for this. Research results offer a way to increase the financial viability of wool-growing farmers, many of whom are currently unable to maintain their lifestyle, resources and infrastructure.  相似文献   
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The 21-kD proteins encoded by ras oncogenes (p21Ras) are modified covalently by a palmitate attached to a cysteine residue near the carboxyl terminus. Changing cysteine at position 186 to serine in oncogenic forms produces a nonpalmitylated protein that fails to associate with membranes and does not transform NIH 3T3 cells. Nonpalmitylated p21Ras derivatives were constructed that contained myristic acid at their amino termini to determine if a different form of lipid modification could restore either membrane association or transforming activity. An activated p21Ras, altered in this way, exhibited both efficient membrane association and full transforming activity. Surprisingly, myristylated forms of normal cellular Ras were also transforming. This demonstrates that Ras must bind to membranes in order to transmit a signal for transformation, but that either myristate or palmitate can perform this role. However, the normal function of cellular Ras is diverted to transformation by myristate and therefore must be regulated ordinarily by some unique property of palmitate that myristate does not mimic. Myristylation thus represents a novel mechanism by which Ras can become transforming.  相似文献   
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Immunohistochemical analysis of adenosine deaminase in rat brain revealed an extensive plexus of adenosine deaminase-containing neurons in the basal hypothalamus. These neurons converged on and were most numerous in three major centers, namely, the tuberal, caudal, and postmammillary caudal magnocellular nuclei. Most other brain regions were devoid of cells containing adenosine deaminase. Some adenosine deaminase-containing neurons were retrogradely labeled with the fluorescent dye fast blue when the dye was injected into the frontal cortex and striatum. Specific populations of neurons having high levels of adenosine deaminase may release adenosine as a neurotransmitter.  相似文献   
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Direct electron microscopy (EM) and enzyme-immunoassay (rotazyme) results for the detection of rotaviruses in 346 enteric specimens from calves, lambs, piglets and foals were compared. The rotazyme test was at least 3 times more sensitive than direct EM in diagnosing infection. Rotavirus antigen was demonstrated by rotazyme in 22% of 280 scour samples and in 27% of 66 samples from non-scouring animals. There was an association between diarrhoea and higher amounts of rotavirus antigen. This prevalence of rotaviruses detected in animals with diarrhoea highlights the significant involvement of other pathogens identified in the study including Eimeria, Cryptosporidia, Escherichia coli, Campylobacter, and other viruses.  相似文献   
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Cardiopulmonary measurements were determined in 19 nonanesthetized, normal ponies. Mean values for arterial pressure, pulmonary arterial pressure, cardiac output, heart rate, packed cell volume, and hemoglobin are reported, as well as acid-base determinations of arterial blood and cerebrospinal fluid. Respiratory function test data include total ventilation, respiratory rate, alveolar ventilation, oxygen uptake, and carbon dioxide output. The data compare favorably with the available data from previous reports on ponies. Because of large day-to-day variations in total ventilation, alveolar ventilation should be measured if ponies are used in the study of pulmonary function.  相似文献   
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