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991.
The ROB-1 beta-lactamase gene from Actinobacillus pleuropneumoniae was cloned and sequenced. The structural gene encodes a 305 amino acid polypeptide. The ROB-1 beta-lactamase gene sequence is identical to that derived from Pasteurella haemolytica and only one amino acid different from that of Haemophilus influenzae, suggesting that they are derived from the same ancestor, and transformed from one to another.  相似文献   
992.
Renal failure associated with infection of Leptospira interrogans was detected in a horse. Fever, leukocytosis, pyuria, isosthenuria, and azotemia were suggestive of an inflammatory urinary tract disease. Despite persistent pyuria, no bacteria were found during routine microscopic examinations or bacteriologic culturing of urine. A fluorescent antibody examination of the urine was positive for L interrogans. Serologic testing during a 6-month period, supported an acute infection with L interrogans serovar pomona. Treatment with intravenously administered fluids and antimicrobials resulted in clinical recovery. Leptospira interrogans serovar pomona has been reported as causing fever, uveitis, or abortion in horses.  相似文献   
993.
Malignant edema (clostridial myositis) was diagnosed in 9 horses with signs of illness that included fever, depression, painful muscular swellings, and toxemia. The infection followed intramuscular injections in 8 horses and developed in a puncture wound in 1 horse. Treatment consisted of surgical fenestration of the involved muscle, high doses of penicillin, nonsteroidal anti-inflammatory agents and analgesics, and supportive fluid therapy. Five horses recovered and 4 died. Those that died had advanced signs of the disease at admission.  相似文献   
994.
After a single IV or IM dose of a long-acting oxytetracycline (OTC) preparation, serum concentrations were determined at various times in the ring-necked pheasant, great horned owl, and Amazon parrot. Pharmacokinetic parameters, including serum half-life (t1/2) and apparent volume of distribution (Vd) were calculated from the OTC concentration-time curves for each species and route of administration. Significant differences (P less than 0.05) were found in the t1/2 and Vd parameters between species and routes of administration. Dosage regimens to maintain minimum OTC concentration of 5 micrograms/ml of serum were calculated from the t 1/2 and Vd values obtained, using steady-state pharmacokinetics. In the pheasant, the calculated mean IV dose was 23 mg/kg of body weight every 6 hours, whereas the mean IM dose was 43 mg/kg every 24 hours. The mean IM dose was 16 mg/kg every 24 hours for the owl and 58 mg/kg every 24 hours for the parrot. The small volumes required for treatment, the long-dosing interval obtainable, and the broad spectrum of antimicrobial activity of the long-acting OTC preparation studied offered major advantages over other antibiotics commonly used in treating avian species.  相似文献   
995.
996.
In situ hybridization (ISH) technique with a biotin-labeled probe was established for detecting feline interleukin 1 (IL-1) alpha mRNA in necropsied specimens. Homology between human IL-1 alpha cDNA used as a probe and feline IL-1 alpha mRNA was confirmed by means of dot blot hybridization using the biotin-labeled probe. Hence, we tried by this biotinylated probe to detect mRNA of IL-1 alpha in paraffin-embedded sections. The following results were obtained for the routine procedures: 1) coating slides with poly-L-lysine and/or heating at 60 degrees C at least for 6 hours gave an excellent result for the adhesion of the tissue sections, 2) 10 micrograms/ml solution of proteinase K treatment for 30 minutes or 50 to 100 micrograms/ml solution of proteinase K treatment for 10 to 30 minutes at 37 degrees C gave the good results in the detection of ISH signal, 3) suitable denaturation time of probes at 70 to 90 degrees C was 5 to 15 minutes, and 4) effective hybridization was obtained by incubation for 24 hours at 4 degrees C, for 18 to 24 hours at 25 degrees C or for 5 to 24 hours at 37 degrees C.  相似文献   
997.
998.
The mitotic index is reported to be correlated with recurrence, mean patient survival, and metastasis of canine hemangiopericytoma (CHP). However, to the authors' knowledge, studies investigating the parameters that can predict recurrence or metastasis of CHP with low mitotic index have not been done. To evaluate growth kinetics of CHP with low mitotic index, a retrospective analysis of the proliferative activity by antiproliferative cell nuclear antigen monoclonal antibody and DNA contents by flow cytometry (FCM) was performed with 21 formalin-fixed and paraffin-embedded CHP samples. Of the 21 tumors evaluated by FCM, 6 (26.6%) were aneuploid tumors, and 15 (71.4%) were diploid tumors. There was significant correlation between the PCNA index and ploidy pattern. The diploid group had 39.1 +/- 9.2 PCNA index, whereas the aneuploid group's proliferative cell nuclear antigen (PCNA) index was 63.1 +/- 8.2. The diploid group had mean mitotic index value of 1.140 +/- 0.855, and the aneuploid group had a mean value of 1.067 +/- 0.767. From these results, the CHP samples with low mitotic index were classified into either the aneuploid group with higher PCNA index or the diploid group with lower PCNA index, suggesting that DNA ploidy and proliferative activity may give an indication about malignancy of CHPs with a low mitotic index.  相似文献   
999.
A diagnosis of light-chain multiple myeloma was made in an 11-year-old male American Shorthair cat. The cat showed atypical plasma cell infiltration in the bone marrow, biclonal gammopathy caused by polymerization of myeloma protein (M-protein), and Bence-Jones proteinuria. The M-protein in the serum of the cat was analyzed by using 12% sodium dodeyl sulfate (SDS) polyacrylamide gel electrophoresis with Coomassie brilliant blue staining. An intense band with a size of 27 kDa, the size of the immunoglobulin light chain, was clearly observed, whereas the band corresponding to the immunoglobulin heavy chain (59 kDa) was undetectable. The 27-kDa band was confirmed to be an immunoglobulin light chain by Western blotting by using antibodies for feline immunoglobulin. These data suggested that the neoplastic plasma cells produce light chain only, leading to the diagnosis of light-chain multiple myeloma in the cat.  相似文献   
1000.
Chromosome observation is necessary to elucidate the structure, function, organization, and evolution of octoploid strawberry plants’ genes and genomes. However, distinguishing strawberries’ chromosomes from one another using light microscopy is extremely difficult, not only because of their small size and large number, but also because current chromosome observation methods are insufficient. Chromosome preparation and staining using maceration enzymes, acetic acid, and DAPI (4′,6-diamidino-2-phenylindole) were improved for this study to obtain clear images of somatic chromosomes in Fragaria vesca (2n = 14) and Fragaria×ananassa (2n = 56). Collected root tips of octoploid plants were placed in 0.002 M 8-hydroxyquinoline solution for 1 h and stored at 4 °C for 16 h. Subsequently, they were fixed using 3:1 absolute alcohol:glacial acetic acid for 40 min, hydrolyzed in the 1N HCl solution at room temperature for 2 h, macerated using an enzyme solution for 25 min at 42 °C, and stained in 1.5% lacto-propionic orcein solution. On the other hand, in case of DAPI staining, the macerated root tips of octoploid plants were soaked in 60% acetic acid for 5 min before staining. Clear digital images of F. vesca and F.×ananassa were obtained using light and fluorescent microscopy. Their respective 14 and 56 chromosomes were counted. Fluorescent microscopy yielded clear chromosome images at the pro-metaphase in F. vesca and F.×ananassa. This chromosome observation method alleviates the difficulties that have heretofore hindered chromosome analyses of strawberry plants.  相似文献   
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