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41.
Crenosoma vulpis and Eucoleus aerophilus are nematode parasites that can cause verminous pneumonia in wild carnivores. There is a paucity of information regarding the distribution of parasites in the lungs and the relationship between histopathological and parasitological diagnoses in naturally infected foxes. The objectives of this study were: first, to study the lobar and airway distribution of C. vulpis and E. aerophilus in wild red foxes and second, to investigate the relationship between fecal and histopathological diagnoses. Samples from 6 sites of the lung and fecal contents were obtained from 51 wild foxes in Prince Edward Island. By fecal examination, 78.4% of wild foxes tested positive for C. vulpis and 68.6% for E. aerophilus. In contrast, 66.6% and 49% of foxes had histopathological evidence of C. vulpis and E. aerophilus in the lungs, respectively. Anatomically, C. vulpis was observed in the small bronchi and bronchioles of all pulmonary lobes whereas E. aerophilus was restricted to the large bronchi and the caudal lobes. Affected airways exhibited severe epithelial glandular hyperplasia and bronchiolar mucous metaplasia. It was concluded that C. vulpis is widely distributed in airways of all pulmonary lobes, whereas E. aerophilus is mainly restricted to the bronchi of caudal lobes. Also, this study showed that histological examination of lung underestimates the infection with E. aerophilus.  相似文献   
42.
Alligators were injected intraperitoneally with four different doses (10, 1.0, 0.1, and 0.01 mg/kg body weight) of a mixture of bacterial lipopolysaccharides (LPS) derived from three different types of bacteria (Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae). Injection of the alligators with the LPS mixture resulted in a dose- and time-dependent increase in total peripheral leukocytes Lymphocytes increased at days 3 and 4 post-injection, and decreased back to baseline levels at day 7 for all doses. Alligators that were not treated, and those injected with pyrogen-free saline, did not exhibit statistically significant changes in total leukocytes during the course of the study. Injection of alligators with 0.5 mg LPS/kg body weight derived from one of three bacterial species revealed that the leukocyte increases observed were not statistically different for all three types of LPS. The animals displayed the same increases in total counts and the levels of all circulating leukocyte types were not different between animals treated with a combination of LPS from all three bacterial species.  相似文献   
43.
Two adult Boxers were evaluated because of chronic dysphagia of several years' duration. Serum creatine kinase activity was high in both dogs, but other hematologic or serum biochemical abnormalities were not detected. Esophagraphy revealed abnormalities of the cricopharyngeal phase of swallowing in both dogs, and electromyography of the pharyngeal and laryngeal muscles revealed complex repetitive discharges, positive sharp waves, and fibrillation potentials characteristic of primary myopathy or neuropathy. Because of the severity of their condition, both dogs were euthanatized. Histologically, mixed-cell infiltrates were seen in sections of the masseter and thyropharyngeal muscles. Results of indirect immunofluorescence staining for proteins associated with dystrophic myopathy were unremarkable, except for decreased staining for integrin alpha7. A diagnosis of chronic inflammatory myopathy was made. The clinical importance of reduced staining for integrin alpha7 could not be determined but was considered to be a result of the myopathy.  相似文献   
44.
香港流感的爆发在全世界产生恐慌 :一种流行的流感毒株正在各地作祟。严格的控制措施抑制了这一疾病 ,但是这种高致病性病毒的许多细节问题还没有弄清楚  相似文献   
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46.
The acoustic reflex (AR) was recorded from 12 healthy mixed-breed dogs. Latency and amplitude were measured from ipsilateral and contralateral AR at stimulus frequencies of 1 and 2 kHz and intensities of 70 to 110 dB sound pressure level for ipsilateral AR and 70 to 120 dB hearing level for contralateral AR. Mean latencies for ipsilateral and contralateral AR were between 33.46 and 206.10 ms and between 45.26 and 180.89 ms, respectively, and amplitudes were between 0.14 and 1.79 cm3 and between 0.31 and 1.86 cm3 of air, respectively. Stimulus frequencies and intensities had significant effects (P less than 0.05) on ipsilateral and contralateral AR latencies and amplitudes. Ipsilateral and contralateral AR decays were determined by measuring compliance change during a 10-s pure-tone stimulation at frequencies of 1 and 2 kHz at an intensity of 10 dB above AR threshold. Reflex decays for 1 kHz and 2 kHz frequencies averaged 5.74% and 9.71%, respectively, for ipsilateral AR and 5.08% and 5.40%, respectively, for contralateral AR. Bilateral tympanograms and brain stem auditory-evoked responses were performed on each dog. Mean normal static compliance of the middle ear, as determined by tympanometry, was 0.15 cm3. Unilateral tenotomy of the tensor tympani muscle was done on 6 of the 12 dogs, and each of the preceding procedures were repeated within 1 week after surgical operation. Transection of the tensor tympani tendon did not alter (P greater than 0.05) the latencies or amplitudes of 1 kHz- or 2 kHz-evoked contralateral AR, the latency or amplitude of 1 kHz-evoked ipsilateral AR, or the amplitude of 2 kHz-evoked ipsilateral AR. However, the latency of 2 kHz-evoked ipsilateral AR was significantly (P less than 0.05) increased. Reflex decay increased significantly (P less than or equal to 0.001) for the contralateral reflex elicited by the 2 kHz stimulus. Neither compliance of the middle ear system nor amplitude and latency of the brain stem auditory-evoked response were affected (P greater than 0.05) by tenotomy. Since tenotomy eliminates participation of the tensor tympani in the AR, these data indicate that contraction of this muscle is not primarily responsible for the compliance changes recorded during an acoustic reflex in dogs.  相似文献   
47.
The Chlamydiales are a unique order of intracellular bacterial pathogens that cause significant disease of birds and animals, including humans. The recent development of a Chlamydiales-specific 16S rDNA polymerase chain reaction (PCR) assay has enabled the identification of Chlamydiales DNA from an increasing range of hosts and environmental sources. Whereas the Australian marsupial, the koala, has previously been shown to harbour several Chlamydiales types, no other Australian marsupials have been analysed. We therefore used a 16S rDNA PCR assay combined with direct sequencing to determine the presence and genotype of Chlamydiales in five wild Australian mammals (gliders, possums, bilbies, bandicoots, potoroos). We detected eight previously observed Chlamydiales genotypes as well as 10 new Chlamydiales sequences from these five Australian mammals. In addition to PCR analysis we used antigen specific staining and in vitro culture in HEp-2 cell monolayers to confirm some of the identifications. A strong association between ocular PCR positivity and the presence of clinical disease (conjunctivitis, proliferation of the eyelid) was observed in two of the species studied, gliders and bandicoots, whereas little clinical disease was observed in the other animals studied. These findings provide further evidence that novel Chlamydiales infections occur in a wide range of hosts and that, in some of these, the chlamydial infections may contribute to clinical disease.  相似文献   
48.
Mammary gland responsiveness to exogenous oxytocin during lactation was assessed by measuring changes in intramammary pressure of healthy sows given (IM injection) synthetic oxytocin (40 U). Response to oxytocin was measured once a week for the first 8 weeks of lactation. Recordings of pressure changes were expressed as mean area (cm2) under the trace at each 10-minute interval over 30 minutes after oxytocin had been given. During the 2nd week of lactation, there was a 55.3% increase (P less than 0.05) in responsiveness to oxytocin (25.1 +/- 4.2 cm2/10 minutes) as compared with the 1st week (13.9 +/- 2.2 cm2/10 minutes). Responsiveness decreased, however, from the 2nd to the 8th week. Since the incidence of mastitis-metritis-agalactia in sows is particularly high during the 1st week of lactation, low responsiveness of the mammary gland to oxytocin may be a contributing factor.  相似文献   
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50.
There is strong evidence that climate change alters tree growth in boreal forests. In Estonia, the analysis of ring measurements has been a common method to study growth changes. In this study, annual height growth data from dominant or co-dominant Scots pine (Pinus sylvestris L.) trees were used to develop a growth model for three forest generations. Stem analysis was applied and annual height growth was measured as the distance between whorls, as detected by branch knots of whorls on the split stem surface. Retrospective analysis of height growth produced comparative trends for three different age groups. Statistical analyses were used to estimate the impact of different factors on growth. Annual height growth was considered the best indicator for detecting possible trends in the growth potential of trees. Study results indicate that three generations (separated by time periods of 30–40 years) showed significant differences in growth patterns caused by shifts in climatic factors and management regimes (anthropogenic and natural disturbances).  相似文献   
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