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971.
972.
Removal of the 2nd or 3rd lumbar vertebrae (or both) has been accomplished in the subhuman primate (Macaca mulatta). Variations between this animal and the dog in posture, vertebral column anatomy, and spinal cord blood supply made no apparent difference in the results when compared with those in previous experiments. All macaques were able to clinb and to use their hind legs in a normal manner within 3 days after surgical operation. Once hair had regrown over the surgical incision, persons not familiar with the animals were not able to identify the animals that had undergone surgical operation. If a single vertebra was removed, use of spinous process and a single vertebral body plate was sufficient to stabilize the vertebral column. Except for 1 rhesus macaque whose spinous process plates were removed 20 days after the operation, vertebral columns of macaques (n = 3) that underwent single spondylectomy healed in nearly normal alignment. With the removal of 2 lumbar vertebrae, the previously described stabilization procedure was not sufficient to prevent kyphotic deformity of the vertebral column. Spinous process plates from 1 macaque were removed after 64 days. However, all these macaques (n = 3) could climb and use their legs as well as others in the colony.  相似文献   
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976.
The medical records of 53 horses with purpura haemorrhagica were reviewed. Seventeen of them had been exposed to or infected with Streptococcus equi, nine had been infected with Corynebacterium pseudotuberculosis, five had been vaccinated with S. equi M protein, five had had a respiratory infection of unknown aetiology, and two had open wounds; the other 15 cases had no history of recent viral or bacterial infection. The horses were between six months and 19 years of age (mean 8.4 years). The predominant clinical signs were well demarcated subcutaneous oedema of all four limbs and haemorrhages on the visible mucous membranes; other signs included depression, anorexia, fever, tachycardia, tachypnoea, reluctance to move, drainage from lymph nodes, exudation of serum from the skin, colic, epistaxis and weight loss. Haematological and biochemical abnormalities commonly detected were anaemia, neutrophilia, hyperproteinaemia, hyperfibrinogenaemia, hyperglobulinaemia and high activities of muscle enzymes. All of the horses were treated with corticosteroids; 42 also received non-steroidal anti-inflammatory drugs and 26 received antimicrobial drugs. Selected cases received special nursing care, including hydrotherapy and bandaging of the limbs. Most of the horses were treated for more than seven days and none of them relapsed. Forty-nine of the horses survived, one died and three were euthanased, either because their severe clinical disease failed to respond to treatment or because they developed secondary complications. Two of the four non-survivors had been vaccinated against S. equi with a product containing the M protein, one had a S. equi infection and the other had a respiratory infection of undetermined aetiology.  相似文献   
977.
978.
Tumours shows aberrant DNA methylation patterns, being hypermethylated or hypomethylated compared with normal tissues. In human acute myeloid leukaemia (hAML) mutations in DNA methyltransferase (DNMT3A) are associated to a more aggressive tumour behaviour. As AML is lethal in dogs, we defined global DNA methylation content, and screened the C‐terminal domain of DNMT3 family of genes for sequence variants in 39 canine acute myeloid leukaemia (cAML) cases. A heterogeneous pattern of DNA methylation was found among cAML samples, with subsets of cases being hypermethylated or hypomethylated compared with healthy controls; four recurrent single nucleotide variations (SNVs) were found in DNMT3L gene. Although SNVs were not directly correlated to whole genome DNA methylation levels, all hypomethylated cAML cases were homozygous for the deleterious mutation at p.Arg222Trp. This study contributes to understand genetic modifications of cAML, leading up to studies that will elucidate the role of methylome alterations in the pathogenesis of AML in dogs.  相似文献   
979.
980.
A total of 291 eight-week-old chickens were exposed to chickens infected with either of two Australian lentogenic strains (V4 and AVL NDV-1) of Newcastle disease virus (NDV). At 3 weeks after exposure, all chickens exposed to V4 infected chickens had developed haemagglutination-inhibition (HI) antibody. All chickens exposed to AVL NDV-1 virus infected chickens had developed HI antibody 5 weeks later. This sudden late appearance of HI antibody, to titres higher than those observed with V4 chickens, was explained by V4 virus being introduced to the AVL NDV-1 group of chickens. When groups of these chickens were challenged with Roakin virus (mesogenic NDV) at 3 weeks and Fontana 1083 virus (viscerotropic velogenic NDV) and Texas GB virus (neutrotropic NDV) at 3, 5, 10 and 21 weeks only three chickens developed clinical illness one of which died. These chickens were one AVL NDV-1 chicken contact challenged with Fontana 1083 virus at 3 weeks, one V4 chicken oronasally challenged with Texas GB virus at 5 weeks and one V4 chicken challenged oronasally with Fontana 1083 virus at 10 weeks. Susceptible non-vaccinated chickens died soon after challenge. Challenge by oronasal infection with 10(7.0) ELD50 of virus or contact with susceptible infected chickens enabled virulent virus to be isolated from most chickens and was accompanied by a large anamnestic increase in serum HI antibody.  相似文献   
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