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81.
Role of litter in the transmission of Campylobacter jejuni   总被引:3,自引:0,他引:3  
Autoclaved or non-autoclaved used broiler litter that was experimentally contaminated with Campylobacter jejuni was capable of infecting specific-pathogen-free chicks maintained in modified Horsfall isolators. Artificially infected chicks became fecal shedders of C. jejuni, resulting in contamination of both autoclaved and non-autoclaved used broiler litter. Fecal shedding of C. jejuni by litter-reared, artificially infected chicks persisted for at least 63 days after chicks were transferred to an isolation unit with a wire floor, which prevented coprophagy. C. jejuni was consistently recovered from water and litter in units housing directly and indirectly infected birds, indicating environmental contamination. These experiments demonstrate the potential role of litter in the perpetuation and transmission of C. jejuni infection in commercial chickens.  相似文献   
82.
To collect biliary samples from pigs, catheters were placed in the distal end of the gallbladders in twelve 20- to 30-kg pigs. An occluder cuff was placed around the bile duct proximal to the duodenum. Inflation of the occluder cuff prevented bile flow into the duodenum and allowed total collection of bile from the catheter in the gallbladder. Deflation of the occluder cuff allowed return of bile flow into the duodenum. Two pigs developed gastric ulcers and two pigs had bile duct dilatation. These responses were attributed to occluder cuffs of inadequate size which could have caused partial or complete obstruction of the bile duct.  相似文献   
83.
Bacillus piliformis infection (Tyzzer's disease) in a calf   总被引:1,自引:0,他引:1  
A 1-week-old Jersey bull calf with a history of diarrhea, weakness, and lethargy was submitted for necropsy. Principal macroscopic findings were enteritis and multifocal necrotizing hepatitis. Histologically and ultrastructurally, organisms with characteristics of Bacillus piliformis were associated with the foci of necrosis in the liver.  相似文献   
84.
The occurrence of leptospirosis in swine of southeastern Alabama was determined. A total of 627 sera were tested, using the microscopic agglutination method, with live antigens of 12 serovars. Of the sera tested, 121 (19.3%) had a titer of 1:100 or greater to the serovars employed. The percentage distribution of sera with titers of greater than or equal to 1:100 among serovars most commonly reported was as follows: Leptospira interrogans serovars pomona, 3.8%; icterohaemorrhagiae, 3.3%; canicola, 1.6%; hardjo, 0.7%; and grippotyphosa, 0.16%. Of the less commonly recognized leptospiral serovars, the percentages reacting were as follows: ballum, 4.9%; autumnalis, 3.2%; pyrogenes, 1.1%; and bataviae, 0.4%. None of the sera reacted with antigen of serovars australis, tarassovi, or wolffi.  相似文献   
85.
Inflammatory polyps of the feline middle ear and nasopharynx are non-neoplastic masses that are presumed to originate from the epithelial lining of the tympanic bulla or Eustachian tube. The exact origin and cause are unknown, however, it is thought that inflammatory polyps arise as a result of a prolonged inflammatory process. It is unclear whether this inflammation initiates or potentiates the development and growth of inflammatory polyps. Cats with inflammatory polyps typically present with either signs of otitis externa and otitis media or with signs consistent with upper airway obstruction. Traditional diagnostics involve imaging of the tympanic bulla either with skull radiographs or computed topography (CT). Treatment consists of traction and avulsion of the polyp with or without ventral bulla osteotomy (VBO) to remove the epithelial lining of the tympanic bulla. The three cases described here are unusual manifestations or presentations of feline inflammatory polyps that address the following issues: (1) concurrent otic and nasopharyngeal polyps, (2) potential association with chronic viral infection, (3) polyp development in the contralateral middle ear, (4) CT appearance of the skull following VBO, and (5) development of secondary pulmonary hypertension.  相似文献   
86.
OBJECTIVE: To determine the pharmacokinetics of gallium maltolate (GaM) after intragastric administration in healthy foals. ANIMALS: 6 healthy neonatal foals. PROCEDURES: Each foal received GaM (20 mg/kg) by intragastric administration. Blood samples were obtained before (time 0) and at 0.25, 0.5, 1, 2, 4, 8, 12, 24, 36, and 48 hours after GaM administration for determination of serum gallium concentrations by use of inductively coupled plasma mass spectroscopy. RESULTS: Mean +/- SD pharmacokinetic variables were as follows: peak serum gallium concentration, 1,079 +/- 311 ng/mL; time to peak serum concentration, 4.3 +/- 2.0 hours; area under the serum concentration versus time curve, 40,215 +/- 8,420 ng/mL/h; mean residence time, 39.5 +/- 17.2 hours; area under the moment curve, 1,636,554 +/- 931,458 ng([h](2)/mL); and terminal half-life, 26.6 +/- 11.6 hours. The mean serum concentration of gallium at 12 hours was 756 +/- 195 ng/mL. CONCLUSIONS AND CLINICAL RELEVANCE: Gallium maltolate administered via nasogastric tube at a dose of 20 mg/kg to neonatal foals resulted in gallium serum concentrations considered sufficient to suppress growth or kill Rhodococcus equi in macrophages and other infected tissues.  相似文献   
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89.
In a prospective-longitudinal study of a representative birth cohort, we tested why stressful experiences lead to depression in some people but not in others. A functional polymorphism in the promoter region of the serotonin transporter (5-HT T) gene was found to moderate the influence of stressful life events on depression. Individuals with one or two copies of the short allele of the 5-HT T promoter polymorphism exhibited more depressive symptoms, diagnosable depression, and suicidality in relation to stressful life events than individuals homozygous for the long allele. This epidemiological study thus provides evidence of a gene-by-environment interaction, in which an individual's response to environmental insults is moderated by his or her genetic makeup.  相似文献   
90.
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