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81.
A crossbred cat developed a subcutaneous fibrosarcoma on the left side of the thorax at the site of previous administration of a feline parvo-, herpes- and calicivirus vaccine. A few months later the cat developed a second mass on the right side of the thorax after a booster vaccine had been administered at this site. This unique case of bilateral fibrosarcomas in a cat shortly after vaccination with parvo-, herpes- and caliciviruses suggests an individual disposition for the development of vaccine-associated sarcomas and a possible triggering of this type of pathological response which could have precipitated the development of the second tumour. To the authors' knowledge, this is the first case of vaccine-induced fibrosarcomas occurring bilaterally after injection of a feline parvo-, herpes- and calicivirus containing vaccine at different sides of the thorax.  相似文献   
82.
Demodex mites are part of the normal fauna of hair follicles of many, if not all, healthy mammal species. Normally these parasites live in harmony with their host, however in states of putative immunosuppression the acarids undergo excessive proliferation and cause clinical disease, which may be localised or generalised. This paper describes four cases of demodicosis in roe deer (Capreolus capreolus) with localised to generalised alopecia.  相似文献   
83.
Two hundred turkey sera from eight Belgian and two French farms were tested for the presence of antibodies against avian pneumovirus (APV), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum, Mycoplasma meleagridis and Chlamydophila psittaci. At slaughter, C. psittaci, APV and ORT antibodies were detected in 94, 34 and 6.5% of the turkeys, respectively. No antibodies against M. gallisepticum or M. meleagridis were present. Additionally, turkeys on three Belgian farms were examined from production onset until slaughter using both serology and antigen or gene detection. All farms experienced two C. psittaci infection waves, at 3-6 and 8-12 weeks of age. Each first infection wave was closely followed by an ORT infection starting at the age of 6-8 weeks, which was still detectable when the second C. psittaci infection waves started. Animals on farm A were not vaccinated against APV leading to an APV subtype B outbreak accompanying the first C. psittaci infection wave. Despite subtype A APV vaccination on farms B and C, the second C. psittaci infection waves were accompanied (farm B) or followed (farm C) by a subtype B APV infection. On all farms respiratory signs always appeared together with a proven C. psittaci, APV and/or ORT infection. This study suggests an association between C. psittaci, APV and ORT, and indicates the multi-factorial aetiology of respiratory infections in commercial turkeys. All three pathogens should be considered when developing prevention strategies for respiratory disease.  相似文献   
84.
The Chrysosporium anamorph of Nannizziopsis vriesii was associated with dermatomycosis and high mortality in a group of captive giant girdled lizards (Cordylus giganteus). Treatment of one of the infected girdled lizards with voriconazole, which was selected on the basis of in vitro sensitivity testing of the isolate, resulted in resolution of lesions and negative fungal cultures from the skin. Three hours after oral administration of 10 mg/kg, the plasma level of voriconazole exceeded the 0.25‐μg/mL minimal inhibitory concentration tenfold. In conclusion, administration of voriconazole at 10 mg/kg of body weight once daily for 10 weeks resulted in clinical cure and was well tolerated. A longer follow‐up time and larger studies will be necessary to determine the long‐term efficacy and safety of this treatment in giant girdled lizards.  相似文献   
85.

The aim of this study was to evaluate the effects of a recruiting maneuver (RM) on lung aeration, gas exchange, and respiratory mechanics during general anesthesia in mechanically ventilated dogs. A thoracic computed tomography (CT) scan, an arterial blood sample, and measurement of respiratory mechanics were performed 10 min before (baseline) and both 5 and 30 min after a vital capacity RM in 10 dogs under general anesthesia. The RM was performed by inflating the lung at 40 cm H2O for 20 s. Lung aeration was estimated by analyzing the radiographic attenuation of the CT images. Lung aeration and gas exchange improved significantly 5 min after the RM compared to baseline and returned to values similar to baseline by 30 min. Static lung compliance was not significantly affected by the RM. An RM induces a temporary improvement in lung function in healthy dogs under general anesthesia.

  相似文献   
86.
随着经济形势发展,要求大学生有一定的实践经验,旧的教学模式重理论而轻实践已经不能适应这种形势。利用实验平台,构建多学科交叉实验体系,建立仿真的实验环境,制定科学合理的实验方法,参与地方经济发展调研活动;培养经贸类大学生的创新意识和实验能力。  相似文献   
87.
We have previously shown that rectally inoculated sheep excrete Escherichia coli O157:H7 during weeks to months without developing a clear antibody response. However, antibodies against this bacterium were observed in naturally infected sheep, which most likely became orally infected. To understand this difference, sheep were orally inoculated with the same Shiga toxin-negative E. coli O157:H7 strain that was used for the rectal inoculation. A primary oral inoculation resulted in shedding of E. coli O157:H7 in the faeces and detection of antibody responses against intimin, EspA and EspB. The antibody titres waned as shedding decreased. A secondary inoculation resulted in longer shedding, even though a booster antibody response occurred. Cellular responses followed a similar pattern as the antibody levels, albeit with a lower secondary response. The presence of antigen-specific antibody-secreting cells indicates involvement of both a systemic response in the spleen and a local immune response in the terminal rectum. These results suggest that E. coli O157:H7 has to pass the small intestine to evoke antibody responses.  相似文献   
88.
Background: Progesterone receptor (PR) antagonist aglepristone (RU534) has been used successfully for pregnancy termination and therapy of pyometra, vaginal tumors, and mammary hyperplasia in bitches and queens. All of these conditions share with canine mammary carcinomas the expression of PR. Objectives: To study the effect of RU534 on proliferation and apoptosis in canine mammary carcinomas in relation to PR expression. Animals: Twenty‐seven nonspayed bitches with mammary carcinomas were treated with either 2 doses of 20 mg/kg RU534 (n = 22, RU534‐treated group) or oil placebo (n = 5, control group) on days 1 and 8. Methods: Tumor samples were collected before (day 1) and after (day 15) treatment for immunohistochemistry. PR expression, proliferation index (PI), and apoptotic index (AI) were determined using antibodies against PR, Ki67, and cleaved lamin A/C antigens, respectively. The effect of treatment on these parameters was analyzed. Results: Differential expression of PR between day 1 (59.1% PR‐positive tumors) and day 15 (36.4% PR‐positive tumors) was observed in RU534‐treated tumors exclusively. After RU534 treatment, mean PI was significantly decreased in PR‐positive but unchanged in PR‐negative RU534‐treated tumors. A reduction of ≥20% in PI was found in 61.5% of RU534‐treated tumors with PR expression. Conversely, no effect on AI was observed after RU534 treatment. Conclusions and Clinical Importance: Neoadjuvant RU534 treatment had PR expression‐related inhibiting effects on proliferation of canine mammary carcinoma cells.  相似文献   
89.
几种常见桑树病害的识别与防治   总被引:1,自引:0,他引:1  
桑树是蚕桑产业的重要物质基础。为确保桑树健康成长,促进产业发展,桑树病害的有效识别与及时防控尤为重要。真核微生物、原核微生物及非细胞类病毒中均存在能引发桑树传染性病害的病原微生物。其中由真核微生物引起的桑里白粉病与桑椹菌核病,原核微生物引起的桑青枯病与桑疫病是爆发频繁、危害极大的桑树病害。本文就这四种桑树病害的病原、侵染循环、病害识别及防治方法等进行系统梳理,并简要介绍几种非细胞类微生物引起的桑树病害,以期为生产上防治相关病害提供参考。  相似文献   
90.
Spinal epidural empyema is defined an accumulation of purulent material in the epidural space of the vertebral canal. Spinal epidural empyema should be considered as a differential diagnosis in dogs with pyrexia, spinal pain, and rapidly progressing myelopathy. Magnetic resonance (MR) imaging is the imaging test of choice in humans. Here, we describe the MR imaging features of five dogs with confirmed spinal epidural empyema. The epidural lesions appeared as high or mixed signal masses in T2-weighted (T2W) images. Increased signal within the spinal cord gray matter at the site of the lesion was detected in T2W images in all dogs. Two patterns of enhancement were detected on postcontrast T1-weighted (T1W) images. Mild to moderate peripheral enhancement was seen in three dogs and a diffuse pattern of enhancement was seen in one. Discospondylitis was identified in three dogs on T1W postcontrast images. Decompressive spinal surgery was performed in all dogs. Bacteria isolated from the abnormal epidural tissue were Enterobacter cloacae, coagulase-positive Staphylococci, Pasteurella multocida, and Escherichia coli. In one dog bacteria were not isolated. These MR imaging features, along with appropriate clinical signs, can allow prompt diagnosis and appropriate treatment planning.  相似文献   
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