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991.
Based on previous studies where tendons receiving the most load have been shown to have the highest levels of cartilage oligomeric matrix protein (COMP), we hypothesized that COMP distribution in articular cartilage may be influenced by mechanical loading. This investigation aimed (a) to describe the pattern of COMP immunoreactivity in middle carpal joint cartilage of two-year-old Thoroughbred horses; (b) to determine topographical variations; (c) to compare high (group 1) and low (group 2) intensity training and (d) to describe COMP immunoreactivity at sites with early osteoarthritis.Group 1 (n =6) underwent a 19 week high-intensity treadmill training programme and group 2 (n =6) were given daily walking until euthanasia. Dorsal and palmar sites on radial and third carpal articular surfaces were prepared. Immunohistochemistry was performed with polyclonal rabbit anti-equine COMP antiserum using a biotin-streptavidin/peroxidase method. Results showed: (a) intracellular immunoreactivity was present in all cartilage zones, but the distribution of COMP staining within the matrix varied between cartilage zones; (b) differences in distribution between sites were not observed, but total COMP levels in exercised horses (n =2) did vary between sites with dorsal sites containing less COMP than palmar sites on the radial, intermediate and third carpal lateral facet; (c) group 1 cartilage showed marked interterritorial distribution in the deep layer compared to group 2 where staining was more generalized throughout the matrix and (d) fibrillated cartilage showed increased local immunoreactivity in the matrix. These findings demonstrate zonal variations in equine COMP distribution which may be influenced by loading.  相似文献   
992.
REASON FOR PERFORMING STUDY: Increased radiopharmaceutical uptake (IRU) in the palmar processes of the distal phalanx is recognised but its clinical significance has not been established. OBJECTIVES: To investigate the relationship between radiographic, scintigraphic and MRI findings in the palmar processes of the distal phalanx. HYPOTHESES: Increased radiopharmaceutical uptake in the palmar processes of the distal phalanx is associated with MRI abnormalities; IRU and MRI abnormalities are over-represented in lame limbs. METHODS: Clinical data, radiographic, scintigraphic and MRI findings of 258 horses with unilateral or bilateral foot pain were recorded. Scintigraphic images were assessed subjectively and using region of interest and profile analysis, and intensity of IRU graded. Alteration in signal intensity in T1 and T2 weighted and short tau inversion recovery (STIR) MR images was documented, and MRI abnormalities graded. Relationships between scintigraphic, MRI, radiographic and clinical findings were assessed. RESULTS: Focal IRU was over-represented in palmar processes with most MRI abnormalities. There was a significant correlation between IRU and MRI grades and IRU was over-represented in palmar processes with MRI Grades 2 and 3. Both IRU and MRI abnormalities occurred most frequently in the medial palmar process. MRI abnormalities were generally over-represented in lame limbs. The most common MRI abnormality was mild diffuse decreased signal intensity in T1 and T2 weighted images, which was associated with mild generalised IRU. CONCLUSIONS: There was considerable variation in the radiographic, scintigraphic and MRI appearance of palmar processes of the distal phalanx. Focal IRU in a palmar process was seen in association with MRI abnormalities and lameness or as an incidental finding. Magnetic resonance imaging abnormalities occurred more frequently in lame limbs, either contributing to lameness or as a consequence of lameness. POTENTIAL RELEVANCE: Further investigation is needed to establish the clinical significance of MRI abnormalities in the palmar processes of the distal phalanx and their relationship with lesions in adjacent structures.  相似文献   
993.
In the late fall of 2004 more severe lesions of porcine circovirus-2 associated disease (PCVAD) than usual occurred during an outbreak of porcine circovirus-2 (PCV-2) infection in Ontario nursery and grower/finisher pigs. The lesions were of unprecedented severity and included diffuse bronchointerstitial pneumonia, granulomatous enteritis, vasculitis, interstitial nephritis, and new lesions of splenic infarction. Some affected herds had up to 50% mortality. The outbreak correlated with the sudden emergence of a variant PCV-2, with PCR restriction fragment length polymorphism (RFLP) type 321. Phylogenetic comparison of ORF2 sequences and full genome sequences showed the new variant to be different from the previously dominant RFLP type 422 viruses, and similar to viruses that had occurred in France and other European and Asian countries. A subsequent retrospective study showed a statistically significant increase in the frequency of histological lesions in lymph node, spleen, lung, small intestine, colon and kidney, for pigs spontaneously infected with RFLP type 321, compared with the older RFLP type 422 strain. Viral burden, based on IHC staining in lymph node, also showed a statistically significant increase in pigs infected with the newer variant RFLP type 321, compared with the older RFLP type 422 strain. This enhanced virulence in pigs infected with PCV-2 RFLP type 321 strain may be related to the genetic differences in this new strain of PCV-2. This virus is now the dominant strain of PCV-2 virus found in Ontario and Quebec swine.  相似文献   
994.
995.
996.
Wildlife rehabilitators are at risk of zoonotic diseases because they often have prolonged contact with many species of wildlife and their bodily fluids. Raccoon roundworm (Baylisascaris procyonis) is a common zoonotic parasite of raccoons that has the potential to cause severe or fatal neurologic disease in a broad variety of hosts if the eggs within raccoon faeces are ingested. We administered an online survey to wildlife rehabilitators to assess their knowledge regarding aspects of transmission, biology and disease caused by B. procyonis, and also to evaluate attitudes towards wildlife diseases and B. procyonis as an occupational hazard. Knowledge was assessed using multiple choice and true–false questions; attitudes were measured using Likert‐type items. A total of 659 complete or near‐complete responses (missing fewer than three knowledge or attitudes items and/or non‐response to some demographic fields) were collected. The median knowledge score was 7/14 questions correct (range: 0–14 correct). Generally, individuals with higher levels of education and rehabilitation experience, veterinary professionals and those who are members of professional wildlife rehabilitation groups scored above the median significantly more often (p < .01). Significantly more rehabilitators who were located in the south‐east and those with part‐time or infrequent commitments scored below the median overall knowledge score. There was general agreement that B. procyonis is a health risk of rehabilitators and that measures should be taken to control transmission to people and animals. Some factors explaining differences in attitudes include setting of rehabilitation (home versus animal care facility), veterinary profession, region, membership in a wildlife rehabilitation group and rehabilitation of raccoons. Findings emphasize the importance of awareness and mentorship to inform rehabilitators on the potential risks of B. procyonis and other potential zoonoses within captive wildlife settings, and the important role of professional wildlife rehabilitator groups in disseminating educational materials.  相似文献   
997.
Baylisascaris procyonis, the raccoon roundworm, is a zoonotic ascarid of importance to human and animal health. Wildlife rehabilitators who care for raccoons may be at an increased risk for exposure to the parasite, especially if proper precautions are not taken. In a wider effort to evaluate awareness regarding B. procyonis in the wildlife rehabilitation community, an online survey (38–39 questions) including questions about B. procyonis knowledge and attitudes was developed and administered to wildlife rehabilitators. To assess precautions taken among raccoon rehabilitators, participants who rehabilitated raccoons (n = 447) answered additional questions about use of personal protective equipment (PPE) and infection control practices (ICPs). Reported use of gloves was variable, but hand hygiene was generally consistent. Masks and gowns were seldom used. Part‐time or infrequent volunteers and rehabilitators located in the Central, Midwest and Southeast were significantly less likely to report consistent use of PPE. A total knowledge score from the survey was used to predict the likelihood of reporting the use of particular ICPs/PPE. Knowledge score had a highly significant but small effect on the likelihood of prophylactic use of anthelmintics, anthelmintics use for B. procyonis specifically, cleaning appropriately, and using species‐dedicated housing. Risk factor analysis was performed on data from a prior serologic survey to evaluate factors associated with exposure to B. procyonis and inconsistent handwashing after contact with live raccoons and their faeces; practising rehabilitation in B. procyonis hyperendemic regions and practising rehabilitation in the western region were significant risk factors for being seropositive. These data further demonstrate that correct PPE/ICPs are critical in mitigating the risk of B. procyonis exposure among raccoon rehabilitators and among other captive species.  相似文献   
998.
加拿大的农户采用合作组织的形式来降低农业机械的购买和使用费用。这种合作组织形式称为居马,与法国合作组织的运作方式类似。加拿大大部分居马成立的原因是奶牛养殖场场主为降低机械成本并解决其他问题(如技术工人短缺等)。另外,生猪饲养、家禽养殖、肉牛养殖等农  相似文献   
999.
Following the detection of the first case of BSE in Japan in September 2001, four million cattle were subjected to a rapid test for BSE up to the end of 2004. A further 10 cases were detected in the dairy cattle population and two cases in Holstein steers. We focused on the dairy population and estimated the prevalence of BSE infected animals within each birth cohort for the years 1992–2001 using Bayesian inference. From this we were able to predict historic and future trends in the number of infected animals culled from each cohort and whether or not they could be detected using a rapid test. Assuming that BSE infectivity entered Japan in 1995, 225 (95%CI: 111–418) infected animals were predicted to have been culled from 1995 to 2001, of which 116 (56–219) would have been slaughtered for human consumption, and 33 (12–65) cases would have been detected during this period if a BSE surveillance program as comprehensive as the one in place as of April 2004 was applied. Assuming that BSE infectivity entered Japan in 1992, 905 (366–4633) infected animals were predicted to have been culled from 1992 to 2001, of which 694 (190–2473) would have been slaughtered for human consumption, and 201 (53–693) cases would have been detected during this period. Assuming the April 2004 level of surveillance continues and that the feed ban introduced in 2001 is completely effective, 18 (3–111) BSE cases are likely to be detected in the future. The BSE epidemic in Japan most likely reached a peak between 1998 and 2001 and should be eradicated around 2012.  相似文献   
1000.
The veterinary profession is currently facing many educational challenges, including an insufficient capacity to train and educate veterinarians for the multiple disciplines within the profession, a shortage of veterinarians in private and public practice, a shortage of faculty, a lack of human and professional diversity, and a rising cost of education resulting in extreme student debt loads. As a methodology for teaching, distance education (DE) has the potential to address many of these issues. By its very nature, DE can increase the capacity of current facilities and faculty. In addition, DE can allow students to acquire the necessary knowledge at less cost. This article describes a model for incorporating DE in the form of interactive Web-based courses, in conjunction with short, intensive residential programs, for the lecture portions of courses taught in the pre-veterinary, veterinary, and post-veterinary educational periods. In this model, the Web-based courses are used to convey the necessary core knowledge required at each step of the educational process. The residential portions are then used to apply the knowledge in such a way as to combine clinical applications with research in basic and applied sciences. Distance education can provide increased flexibility, high-quality educational experiences, and a less costly alternative for students while maximizing the reach of current faculty efforts and the capacity of existing physical structures.  相似文献   
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