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A not pregnant 4-year-old Jersey cow was presented with the sudden appearance of respiratory noise, nasal discharge and moderate respiratory difficulty. Upon physical examination a snoring-like noise, extended head and neck position, exaggerated abdominal effort, bilateral nasal discharge and left prescapular lymph node enlargement were noted. Sub-occlusion of the initial portion of the respiratory tract was suspected. Radiographic and endoscopic examinations revealed a pedunculate mass on the dorsal aspect of the rhinopharynx, which was removed with endoscopically assisted electrosurgery. Histologic examination revealed a chronic pyogranulomatous inflammation with eosinophilic club-like bodies surrounding small colonies of rod-shaped bacteria. Results of histochemical staining were consistent with Actinobacillus-like bacteria and a diagnosis of respiratory actinobacillosis was reached. Surgery and antibiotic therapy were resolutive, as demonstated by an endoscopic check at the second month after surgery, even without the association of the traditional iodine cure, which is regarded as the treatment of choice for actinobacillosis.  相似文献   
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Veterinary Research Communications -  相似文献   
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Research on the application of innovative biodegradable materials for substrate mulching in greenhouse floricultural cultivation was carried out in Southern Italy. A transparent biodegradable film and a transparent biodegradable spray coating were compared with a commercial transparent low density polyethylene film. The biodegradable film was a starch based extruded material, the sprayed coating was created from a polysaccharide solution. The materials were used to mulch the peat and perlite growing media contained in trays during snapdragon cultivation in order to increase the substrate temperature and hasten early growth. The climate variables inside and outside the greenhouse and the growing medium temperature under the mulching materials were recorded. Biometrical data, such as mean blooming time, plant height and spike length, were collected. The laboratory radiometric tests showed that the biodegradable mulching materials had a lower solar transmissivity in comparison to the low density polyethylene film. The capacity to reduce the long wave infrared thermal losses was higher for the biodegradable mulches: the long wave infrared transmissivity coefficient was 53.9% for the low density polyethylene film, 12.1% for the biodegradable film and 8.2% for the spray coating. The increase of the growing medium temperature allowed the harvest of the snapdragon grown in the mulched trays 7 days before that of the flowers grown in the un-mulched trays. At the end of the crop cycle the disposal of the biodegradable mulching materials was carried out fragmenting and mixing them with plant residue and the growing medium. The residue biodegraded in almost 1 month for the spray coating and in about 12 months for the biodegradable film.  相似文献   
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The objective of this study was to describe method of placement, and frequency and severity of complications associated with a subpalpebral lavage system placed in the medial aspect of the equine inferior eyelid. The inferomedial subpalpebral lavage (ISPL) tube is positioned deep in the medial aspect of the inferior conjunctival fornix so that the footplate lies flat between the lower eyelid and the anterior surface of the nictitans. Retrospective data from the placement of 92 ISPL systems placed in 86 horses during a 31-month period were examined. Tube placement was performed using sedation and regional anesthesia only in 59% of horses. The median duration of tube placement was 19 days (range: 1-61 days). Seventy-one horses were treated for up to 55 days following discharge from hospital with an ISPL tube in place. No complications were reported with 59% of ISPL systems. Non-ocular complications were found in 38% of ISPL systems and included tube displacement from the conjunctival fornix (18%), suture loss requiring resuturing of the system to the horse's head (14%), and damage necessitating replacement of the injection port (6%). Ocular complications were recorded in 3% of horses and were limited to inferior eyelid swelling. Vision was retained in 88% of horses. The ISPL system is easily and safely placed, and well tolerated for extended periods. It appears to be associated with infrequent and minor complications when compared with placement of subpalpebral lavage tubes in the superior eyelid.  相似文献   
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Execution of motor behaviors relies on circuitries effectively integrating immediate sensory feedback to efferent pathways controlling muscle activity. It remains unclear how, during neuromuscular circuit assembly, sensory and motor projections become incorporated into tightly coordinated, yet functionally separate pathways. We report that, within axial nerves, establishment of discrete afferent and efferent pathways depends on coordinate signaling between coextending sensory and motor projections. These heterotypic axon-axon interactions require motor axonal EphA3/EphA4 receptor tyrosine kinases activated by cognate sensory axonal ephrin-A ligands. Genetic elimination of trans-axonal ephrin-A --> EphA signaling in mice triggers drastic motor-sensory miswiring, culminating in functional efferents within proximal afferent pathways. Effective assembly of a key circuit underlying motor behaviors thus critically depends on trans-axonal signaling interactions resolving motor and sensory projections into discrete pathways.  相似文献   
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Group B Streptococcus (GBS) is a multiserotype bacterial pathogen representing a major cause of life-threatening infections in newborns. To develop a broadly protective vaccine, we analyzed the genome sequences of eight GBS isolates and cloned and tested 312 surface proteins as vaccines. Four proteins elicited protection in mice, and their combination proved highly protective against a large panel of strains, including all circulating serotypes. Protection also correlated with antigen accessibility on the bacterial surface and with the induction of opsonophagocytic antibodies. Multigenome analysis and screening described here represent a powerful strategy for identifying potential vaccine candidates against highly variable pathogens.  相似文献   
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Objective To characterize conjunctival lymphoid nodules obtained from the nictitans of healthy cats to determine if the follicle‐associated epithelium (FAE) of conjunctiva‐associated lymphoid tissue (CALT) in this species contains membranous (M)‐cells analogous to those described in other regions of mucosa‐associated lymphoid tissue (MALT). Methods Lymphoid follicles from nictitan bulbar surfaces of 10 healthy cats (20 eyes total) were examined. Nictitans from five cats were harvested immediately post‐mortem and a minimum of 12 lymphoid nodules from each third eyelid were isolated using a Zeiss operating microscope. At least three lymphoid follicles from each eye were examined using light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) using standard fixation and embedding protocols. Nictitan‐lymphoid follicles from another five healthy cats were processed for immunohistochemistry to characterize the distribution of T‐ and B‐lymphocytes present beneath the FAE. Results The FAE overlying CALT from 10 healthy cats demonstrated morphology characteristic of M‐cells including attenuated apical cell surface with blunted microvilli and microfolds, invaginated basolateral membrane forming a cytoplasmic pocket, and diminished distance between the apical and pocket membrane. Immunohistochemistry of lymphoid tissue subtending the FAE demonstrated B‐cell dependent regions in the germinal centers surrounded by T‐cell dependent interfollicular zones. Conclusions Healthy feline CALT contains morphologic features analogous to those described in other regions of MALT. Documentation of feline conjunctival M‐cells is of clinical relevance in the study of primary infectious, allergic, and autoimmune ocular diseases, as well as a potential means of vaccination or drug delivery.  相似文献   
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