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691.
Toxoplasma gondii infection is widely prevalent in humans in Brazil. Among the food animals, pigs are considered the most important meat source of T. gondii for infection in humans. In the present study, we report the first isolation of viable T. gondii from finishing pigs in Brazil. Antibodies to T. gondii were found in 49 (17%) of 286 pigs prior slaughter using the modified agglutination test (MAT) at a serum dilution of 1:25. Attempts were made to isolate T. gondii from 28 seropositive pigs. Samples of heart, brain, and tongue from each pig were pooled, digested in acid pepsin, and bioassayed in five mice per pig. Viable T. gondii was isolated from seven pigs; all isolates were lethal for mice. Restriction fragment length polymorphism on products of SAG2 locus amplified by PCR revealed that two isolates were Type I and five were Type III. The results indicate that phenotypically and genetically T. gondii isolates from pigs from Brazil are distinct from isolates of T. gondii from pigs in the USA.  相似文献   
692.
A 4-year-old, neutered male Maltese presented with a 2-month history of right hemiparesis. The radiographic findings revealed bone lysis, and sclerotic changes in the right section of the fifth and sixth cervical bones with a mild radiolucent mass around the lesion. The magnetic resonance imaging revealed a hyperintense mass located in the region extending from the muscles to the bones and compressing the spinal cord. The mass was removed via a hemilaminectomy in the cervical area using the ventral and dorsal approach, and a histological examination confirmed that it was adipose tissue. An infiltrative lipoma was diagnosed based on these findings. The dog has ambulated normally for 24 months since undergoing surgery.  相似文献   
693.
Typing of Haemophilus parasuis strains by PCR-RFLP analysis of the tbpA gene   总被引:13,自引:0,他引:13  
On the basis of a species-specific PCR assay, a RFLP analysis for typing of Haemophilus parasuis strains was developed and evaluated. Amplification was based on the gene tbpA, encoding a transferrin-binding protein. RFLP analysis of the 1.9-kb tbpA-amplicon using TaqI, AvaI and RsaI endonucleases produced 12 different patterns for the reference strains of the 15 known H. parasuis serovars, and showed a high heterogeneity (33 RFLP groups) for 101 H. parasuis clinical isolates tested. The sensitivity, typeability (100% versus 65% for immunodiffusion), high degree of discrimination (0.93 versus 0.84 for immunodiffusion), simplicity and low cost per test make this PCR-RFLP assay a useful method for typing H. parasuis and, therefore, for studying the epidemiology of outbreaks of Gl?sser's disease.  相似文献   
694.
Immunity to Listeria monocytogenes is largely mediated by T lymphocytes. Recently, B lymphocytes or their secreted products are implicated to provide immunity against L. monocytogenes infection. To understand whether L. monocytogenes can infect and kill B cells as a possible strategy to initiate an infection, we examined the effects of L. monocytogenes on a human B lymphoma (Ramos RA-1) and mouse primary B cells in vitro. L. monocytogenes infection resulted in significantly (p相似文献   
695.
The electroencephalographic (EEG) effects of a rapid infusion of midazolam and sarmazenil following a bolus of midazolam were investigated in eight Welsh mountain ponies anaesthetized with 0.8% halothane in oxygen. The peak plasma concentration of midazolam was 2.13 +/- 0.34 ng/mL (mean +/- SD) occurring 5 min after the start of the infusion. Sarmazenil concentrations were not measured. The 95% spectral edge frequency of the EEG decreased by a maximum of 39.8 +/- 15.8%, 10 min after the start of the midazolam infusion. No changes were seen in median frequency of the EEG or the second differential of the middle latency auditory evoked response. The variability of median frequency (F50) and spectral edge frequency (F95) were reduced by a maximum of 80 +/- 7 and 84 +/- 7%, respectively. The sarmazenil infusion reversed the effects of a bolus of midazolam on the variability of F50 and the magnitude and variability of F95. The second differential of the middle latency auditory evoked potential (DD) was increased by 56.4 +/- 69.3%, 10 min after the start of the sarmazenil infusion. There were no statistically significant differences in EEG variables between the baseline of the midazolam infusion and 10 min after the start of the sarmazenil infusion. Midazolam infusion resulted in specific and unusual changes in the EEG of anaesthetized ponies. These changes were completely reversed by sarmazenil infusion. The data presented suggest that sarmazenil has no intrinsic effect upon the EEG.  相似文献   
696.
Abstract: A 6-year-old Rottweiler was presented to the North Carolina State University College of Veterinary Medicine for evaluation of multiple cutaneous nodules. The dog had a history of anorexia, vomiting, and hind-limb paraplegia. Results of cytologic examination of the cutaneous nodules were consistent with a round cell tumor. At necropsy, primary tumors were found coalescing in the duodenum and the pancreas and extending into the associated mesentery. Numerous masses also were found throughout the skin, abdominal and thoracic viscera, and lumbar spinal cord. Histologically, the duodenal tumor had variable morphology, with some areas resembling adenocarcinoma and others resembling anaplastic round cell neoplasia; the skin and other metastatic lesions resembled round cell neoplasia. Immunohistochemistry of the cutaneous, duodenal, and pancreatic masses showed the neoplastic cells were positive for pancytokeratin, supporting an epithelial origin. In addition, low numbers of neoplastic cells were positive for periodic acid-Schiff and Alcian blue, consistent with acid mucin production by duodenal epithelium. These findings confirmed that the cutaneous nodules were metastatic lesions originating from the duodenal adenocarcinoma. Cutaneous metastasis of intestinal carcinoma is rare in domestic animals. This case demonstrates the potential difficulty in diagnosing metastatic lesions based on cytologic and histologic morphology alone, because the cutaneous metastases may not resemble the primary neoplasm morphologically.  相似文献   
697.
OBJECTIVE: To determine historical, physical examination, hematologic, and serologic findings in dogs with Ehrlichia ewingii infection. DESIGN: Retrospective study. ANIMALS: 15 dogs. PROCEDURE: In all dogs, infection with E ewingii was confirmed with a polymerase chain reaction (PCR) assay. Follow-up information and clarification of information recorded in the medical records was obtained by telephone interviews and facsimile correspondence with referring veterinarians and owners. RESULTS: Fever and lameness were the most common findings with each occurring in 8 dogs. Five dogs had neurologic abnormalities including ataxia, paresis, proprioceptive deficits, anisocoria, intention tremor, and head tilt. Neutrophilic polyarthritis was identified in 4 dogs. No clinical signs were reported in 3 dogs. The predominant hematologic abnormality was thrombocytopenia, which was identified in all 12 dogs for which a platelet count was available. Reactive lymphocytes were seen in 5 of 13 dogs. Concurrent infection with another rickettsial organism was identified in 4 dogs. Of the 13 dogs tested, 7 were seroreactive to E canis antigens. Morulae consistent with E ewingii infection were identified in neutrophils in 8 dogs. Treatment with doxycycline, with or without prednisone, resulted in a rapid, favorable clinical response in the 9 dogs for which follow-up information was available. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that PCR testing for E ewingii infection should be considered in dogs with fever, neutrophilic polyarthritis, unexplained ataxia or paresis, thrombocytopenia, or unexplained reactive lymphocytes, and in dogs with clinical signs suggestive of ehrlichiosis that are seronegative for E canis. Following treatment with doxycycline, the prognosis for recovery is good.  相似文献   
698.
OBJECTIVE: To determine clinical characteristics of and outcome in Thoroughbred racehorses with tibial or humeral stress fractures. DESIGN: Retrospective study. ANIMALS: 99 Thoroughbreds with tibial or humeral stress fractures. PROCEDURE: Information obtained from the medical records included history, signalment, and clinical, radiographic, and scintigraphic findings. Outcome was determined by interviewing trainers, performing follow-up examinations, and analyzing race records. RESULTS: Seventy-four tibial stress fractures were identified in 61 Thoroughbreds, and 48 humeral stress fractures were identified in 39 Thoroughbreds (1 horse was included in both groups). Tibial stress fractures occurred most commonly in 2-year-old or unraced horses. Fractures were located in 1 of 3 sites in the tibia (most commonly, the caudolateral cortex of the mid-diaphysis) and 1 of 4 sites in the humerus (most commonly, the caudodistal cortex). Forty-four of 58 (76%) tibial stress fractures and 18 of 32 (56%) humeral stress fractures were identified radiographically. Humeral stress fractures involving the caudodistal cortex were not detected radiographically. Treatment consisted of rest and exercise restriction, and 49 of 61 (80%) horses with tibial stress fractures and 30 of 39 (77%) horses with humeral stress fractures returned to racing. Humeral stress fractures recurred in 6 horses. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that in Thoroughbred racehorses, tibial stress fractures occurred most commonly in unraced 2 year olds, whereas humeral fractures occurred most commonly in older horses that had raced previously. The prognosis for racing following treatment was good.  相似文献   
699.
The identification of lactic acid bacteria in a complex microbiota using bacteriological culture in combination with phenotypic and genotypic identification techniques is laborious and time-consuming. New molecular methods permit a fast and culture-independent characterisation of such microbiota. Denaturing gradient gel electrophoresis (DGGE) of PCR fragments of the 16S rRNA gene has been proven to be a suitable tool. Here the use of PCR-DGGE with group specific primers is described to investigate the dynamic of sourdough microbiota from addition of the starter until the microbiota remained stable. Species were identified by applying an identification ladder obtained from reference strains or by sequence analysis of the PCR fragments. Furthermore, a method for detection of strains in complex microbiota is described. A strain specific chromosomal DNA fragment of Lactobacillus paracasei LTH 2579 was isolated applying the subtraction hybridisation. Based on the acquired target sequence a specific PCR system was established and combined with a PCR system specific for the species L. paracasei. Use of this detection system permitted to identify and quantitatively detect L. paracasei LTH 2579 in fermented sausages and upon consumption in faecal samples.  相似文献   
700.
Humeral fractures are rare and usually carry a guarded prognosis in adult horses. This paper describes the evaluation and the successful surgical management of a fracture of the lateral supracondyloid crest and part of the epicondyle of the humerus in an adult quarter horse.  相似文献   
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