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Hemophilia A is an X‐chromosome‐linked disorder caused by a deficiency in factor VIII (FVIII). Although foals have been diagnosed with hemophilia A based on deficiency in FVIII activity, causative gene mutations have not been identified. The genomic DNA and cDNA encoding FVIII of a Tennesee Walking Horse colt affected with hemophilia A and the genomic DNA of his dam and a normal unrelated horse were analyzed with no splice site or coding sequence abnormalities identified in any of the horses. Polymerase chain reactions (PCR) were then performed on hepatic cDNA from the affected colt and an unrelated normal horse, and no product was obtained for the sequence between and including exon 1 and exon 2 in the affected colt. Based on these results, suspected mutations were identified in the noncoding region of FVIII (intron 1), and genomic sequencing of intron 1 in the dam and the affected colt suggested maternal inheritance.  相似文献   
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Edotoxin was detected, using the limulus amebocyte lysate (LAL) test, in the blood of 3 sheep and 1 steer which had been experimentally "overfed" (induced grain engorgement) with a mixture of corn and oats (2:1). The 1st postfeeding blood samples were collected 24 hours after overfeeding. In 2 sheep and 1 steer, the 24-hours blood samples were test positive. In 1 sheep which died, the 48-hour blood sample was the 1st test-positive sample. In all cases, pre-overfeeding blood samples were taken just before overfeeding.  相似文献   
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The clinical efficacy of becaplermin (Regranex, Ortho-McNeil Pharmaceutical, Inc., Raritan, New Jersey 08869) on head and lateral line erosion syndrome (HLLES) in ocean surgeonfish (Acanthurus bahianus) was examined in a two-part study to determine suitable application frequencies of the drug and the effects of the environment on outcome of treatments. In the first part of the study, 12 ocean surgeonfish with prior HLLES were equally divided into three treatment groups, varying in application frequency of becaplermin: 1) one application, 2) three applications every 3 wk, and 3) no applications. After 9 wk, it was determined through photograph and computer analysis that fish treated with becaplermin did heal significantly more than the fish that were not treated. No significant difference was found when comparing the two treatment regimes; therefore, a one-time treatment of becaplermin was just as effective as the three-time application, reducing cost of the treatment, staff labor, and stress to the animals. In the second part of the study, the effect of the water environment on HLLES development was documented before and after a one-time treatment of becaplermin. When fish were treated and placed into a system known to cause HLLES, the becaplermin treatment had no effect on reducing the HLLES progression, whereas treated fish that were placed into a system that did not cause HLLES showed a significant decrease in erosion after the treatment. Therefore, treating fish being placed into a HLLES-causing system serves no beneficial purpose to healing HLLES.  相似文献   
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Helical computed tomography angiography was used to evaluate the renal vascular anatomy of potential feline renal donors. One hundred and fourteen computed tomography angiograms were reviewed. The vessels were characterized as single without bifurcation, single with bifurcation, double, or triple. Multiplicity was most commonly seen for the right renal vein (45/114 vs. 3/114 multiple left renal veins, 0/114 multiple right renal arteries, and 8/114 multiple left renal arteries). The right kidney was 13.3 times more likely than the left to have multiple renal veins. Additional vascular variants included double caudal vena cava and an accessory renal artery. For the left kidney, surgery and computed tomography angiography findings were in agreement in 92% of 74 cats. For the right kidney, surgery and computed tomography angiography findings were in agreement in 6/6 cats. Our findings of renal vascular anatomy variations in cats were similar to previous reports in humans. Identifying and recognizing the pattern of distribution of these vessels is important when performing renal transplantation.  相似文献   
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