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Reduced levels of total iron binding capacity and unsaturated iron binding capacity were observed in the blood of trichinous and iron-injected trichinous pigs. No change was observed in their serum iron and saturation concentration levels. Also, reduced iron concentration levels were observed in the livers of trichinous pigs, while increased iron concentration levels were observed in the spleens of trichinous pigs and the livers and spleens of iron-injected pigs. No difference was found with regard to weight gains, number of larvae per gram of tissues, or histologic characteristics of 'nurse cells'.  相似文献   
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Horseshoeing is a common practice, but effects on the hoof wall are poorly understood. Strain gauges were used to document and compare hoof behavior in vitro during flat weight bearing and after artificial heel elevation. Ten front limbs of Thoroughbred race horses, shod with conventional flat shoes, were used. Eight strain gauges were symmetrically distributed around the toe, quarters, and heels. Each limb was mounted to a testing machine (Kratos K5002; Kratos Dynamômetros, Ltda., Cotia-SP-Brazil) and subjected to a load equivalent to 30% of the donor's body weight. Strains (μ) were acquired by means of a computerized system and the results compared using Friedman and Wilcoxon statistical tests. There was greater strain variation when the heels were elevated. Compression predominated during flat weight bearing, with a tendency to horizontal traction after heel elevation. The changes in strain caused by heel elevation were not always symmetrical. Elevation of the heels tensed the toe and the medial quarter horizontally, increased load at the posterior portion of the hoof capsule, and hindered its expansion.  相似文献   
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The peripheral blood response to intramuscular injection of 10 units ACTH in dogs was investigated because no experimental evidence for the standardization of this procedure for clinical use was available. Following the injection of ACTH in sodium chloride solution, neutrophilia, monocytosis, eosinopenia, and lymphopenia occurred. With the exception of eosinopenia, the greatest change in the concentration of each cell type in peripheral blood occurred between 2 and 4 hours post injection. The maximum change in eosinophil numbers occurred between 4 and 6 hours post injection. When all cell types were considered, 4 hours post injection was the most suitable time to measure the cellular response in peripheral blood in dogs which respond to ACTH. The data indicate that change in the ratio of neutrophils to lymphocytes (N/L) prior to and at 2 to 4 hours after ACTH injection in normal dogs was a sensitive index of response and occured sooner than eosinopenia. The extent of change in the N/L ratio was such that accuracy in interpretation could be obtained by counting as few as 40 cells.  相似文献   
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The objective was to investigate the RNA synthesis in porcine blastomere nuclei upon transplantation into in vitro matured enucleated oocytes. Nuclei from 2- to 8-cell porcine embryos were introduced into the ooplasm of in vitro matured and enucleated porcine oocytes by electrofusion, and the resultant reconstructed embryos were cultured in vitro. Before fusion or at different intervals after this event embryos were incubated with [3H]-uridine, fixed, and histologically processed for autoradiography in order to detect RNA synthesis. About two thirds of the embryos were considered to depict normal development. All blastomeres displayed pronounced RNA synthesis before fusion, at 3 and 9 h after fusion the synthesis decreased or ceased, and at 24-49 h some embryos resumed synthesis at the 1- to 2-cell stage.  相似文献   
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Previous attempts to transfer embryos non-surgically to heifers have been rather discouraging. The present experiment describes a simple non-surgical technique where the 6½–7½ -day old embryo is placed in a 0.25 ml ministraw, fitted into a common insemination gun and transferred cervically to synchronized lactating dairy cows. Thirty-two viable embryos were transferred to the middle part of the uterine horn ipsilateral to the ovary containing the corpus luteum. It was easy to pass the cervix, and most embryos could be deposited in the horn within 1 or 2 min. Eighteen animals were diagnosed pregnant (56% ). It is conceivable that the easy atraumatic transfers and good management (feeding, oestrus control) of the recipients contributed to the high pregnancy rate.  相似文献   
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Cell wall disassembly in ripening climacteric fruit is a highly complex process where ethylene plays a crucial role. Ethylene inhibitors can be used to explore the changes in the cell wall matrix and cross-linked polysaccharides in ethylene-regulated processes. The results of applying the ethylene receptor blocking inhibitor 1-methylcyclopropene (1-MCP) and the ethylene-releasing compound ethephon (2-chloroethylphosphonic acid) indicate that softening of ‘Maradol’ papaya fruit is dependent on ethylene. When fruit were induced to ripen extensively by exposure to a high dose of ethephon, 1-MCP inhibited the subsequent softening dramatically, but when inhibition of the ethylene response was caused by application of 1-MCP, subsequent fruit treatment with ethephon promoted extensive loss of galactose from the water-soluble polysaccharides, but this was not accompanied by fruit softening. The cell wall changes accompanying normal fruit softening were pectin solubilization and polyuronide depolymerization and these processes occurred simultaneously. Polygalacturonase likely is responsible for the ripening-associated changes in ‘Maradol’ papaya fruit texture and pectin polymer integrity. An increase in extractable fruit polygalacturonase follows the increased presence of pectin-derived oligosaccharides.  相似文献   
10.
Accumulation in soil and leaching to groundwater of fentin acetate were studied in the laboratory using two types of Dutch sandy soil differing in organic matter content. Mobility, adsorption, transformation and formation of intermediates were determined in unsaturated soil columns, batch shaking systems and soil incubation systems. Samples were analyzed for monophenyltin, diphenyltin and triphenyltin compounds after methylation. Therefore the transformation products diphenyltin oxide and phenyltin acid were determined separately. Both were detected in soil and pore water. Adsorption indicated that these fungicides are immobile in both types of soil. Nevertheless a small fraction was found in the column leachate. After 1 yr of percolation 5.5 and 20.2% of the dose was recovered as total phenyltin residue in the soil of low and high organic matter content, respectively; all the residue was in the upper 10 cm. The half-life of fentin acetate in soil with 1% organic C varied between 47 and 70 days and between 115 and 140 days in soil with 2% organic C. If fentin acetate is applied annually, one can expect to find an ultimate accumulation level of organotin residues of up to 25% of the annual dose in the plough layer.  相似文献   
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