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1.
Quantitative risk assessments are now required to support many regulatory decisions involving infectious diseases of animals. Current methods, however, do not consider the relative values of historical and recent data. A Markov-chain model can use specific disease characteristics to estimate the present value of disease information collected in the past. Uncertainty about the disease characteristics and variability among animals and herds can be accounted for with Monte Carlo simulation modeling. This results in a transparent method of valuing historical testing information for use in risk assessments. We constructed such a model to value historical testing information in a more-transparent and -reproducible manner. Applications for this method include trade, food safety, and domestic animal-health regulations.  相似文献   

2.
Simulation modeling can be used in aiding decision-makers in deciding when to invest in additional research and when the risky animal disease-import decision should go forward. Simulation modeling to evaluate value-of-information (VOI) techniques provides a robust, objective and transparent framework for assisting decision-makers in making risky animal and animal product decisions. In this analysis, the hypothetical risk from poultry disease in chicken-meat imports was modeled. Economic criteria were used to quantify alternative confidence-increasing decisions regarding potential import testing and additional research requirements. In our hypothetical example, additional information about poultry disease in the exporting country (either by requiring additional export-flock surveillance that results in no sign of disease, or by conducting additional research into lack of disease transmittal through chicken-meat ingestion) captured >75% of the value-of-information attainable regarding the chicken-meat-import decision.  相似文献   

3.
The medullary rim sign is a distinct hyperechoic line in the renal medulla parallel to the corticomedullary junction that has been reported in dogs with a variety of renal diseases. To examine the association between medullary rim sign and renal disease, the medical records of thirty-two dogs that had medullary rim sign were reviewed retrospectively. Eighteen dogs (56%) had no evidence of renal dysfunction; 14 (44%) had clinicopathological evidence of renal disease, including 6 (19%) that had hypercalcemic nephropathy. Most dogs (72%) in which medullary rim sign was the only ultrasonographic finding affecting the kidneys had no evidence of renal dysfunction. In contrast, 78% dogs that had medullary rim sign and other renal signs (reduced size, increased medullary echogenicity, and pyelectasia) had renal disease. On the basis of this study, the medullary rim sign appears to be a non-specific ultrasonographic sign; however, the possibility cannot be excluded that is a sentinel sign of subclinical renal disease.  相似文献   

4.
An echogenic line in the outer zone of the renal medulla, paralleling the corticomedullary junction is described as the renal medullary rim sign. This renal ultrasonographic change is demonstrated in 4 dogs and 2 cats with a range of renal diseases. The renal medullary rim sign provides additional ultrasonographic criteria indicating primary renal disease in some patients. However the renal medullary rim sign may prove to be a poor correlate for prognosis across the range of differentials present in these clinical patients.  相似文献   

5.
Feline corneal disease   总被引:1,自引:0,他引:1  
The cornea is naturally transparent. Anything that interferes with the cornea's stromal architecture, contributes to blood vessel migration, increases corneal pigmentation, or predisposes to corneal edema, disrupts the corneas transparency and indicates corneal disease. The color, location, and shape and pattern of a corneal lesion can help in determining the underlying cause for the disease. Corneal disease is typically divided into congenital or acquired disorders. Congenital disorders, such as corneal dermoids are rare in cats, whereas acquired corneal disease associated with nonulcerative or ulcerative keratitis is common. Primary ocular disease, such as tear film instability, adenexal disease (medial canthal entropion, lagophthalmus, eyelid agenesis), and herpes keratitis are associated with the majority of acquired corneal disease in cats. Proliferative/eosinophilic keratitis, acute bullous keratopathy, and Florida keratopathy are common feline nonulcerative disorders. Nonprogressive ulcerative disease in cats, such as chronic corneal epithelial defects and corneal sequestration are more common than progressive corneal ulcerations.  相似文献   

6.
7.
Spatial analysis provides a powerful method to test epidemiologic hypotheses about patterns of disease occurrence. Available techniques can be classified based on the type of data which they utilize, generally areas or points, and the primary question of interest. Three issues relevant to epidemiology are: whether a disease is clustered; whether two diseases or a disease and potential risk factor have the same distribution; and if there are specific definable relationships between the values of the same variable at different locations. Join count statistics, which relate actual and expected number of joins between areas with dissimilar values, and second order analysis, which compares the actual and expected distances between all points weighted by their values, give estimates of the magnitude and statistical significance of clustering in patterns. To test for codistribution between areal patterns, the kappa statistic evaluates the degree of pattern overlap corrected for chance. Tjosteim's statistic measures the correlation, corrected for point locations, of the ranked values. Spatial autocorrelation analysis can be used to test for specific network and distance associations between values, for the scale of a pattern, for defined complex spatial relationships or to remove spatial effects from more traditional regression analysis of other risk factors. Epidemiologists have uncovered spatial associations between diseases and risk factors using traditional methods. However, more widespread application of spatial analyses to objectively quantify the magnitude and significance of hypothesized geographical associations could offer new insights into disease questions.  相似文献   

8.
The analysis of laboratory data can provide information about the health of livestock populations; in Great Britain the Veterinary Investigation Diagnosis Analysis (VIDA) system has provided such data since 1975. However VIDA covers only known diagnoses, with limited epidemiological characterisation. The unexpected outbreak of bse showed that it was necessary to improve surveillance to detect new diseases, and a necessary update of the VIDA database for the millennium date change provided the opportunity. The information required to enhance the value of laboratory data was identified, a new form and database, 'FarmFile', were designed to record it, and they began to be used in 1999. The detection of new diseases depends on making comparisons with the expected or 'usual' levels of unexplained disease. The data are analysed quarterly to assess any changes in the levels of unexplained disease in different species, categorised in terms of clinical sign or body system, by comparison with previous years. No new diseases have been detected either through FarmFile or more traditional means since the new analyses started in earnest in 2004, but they have indicated that an unexplained event was not a new disease of concern, and developments continue to improve the system's sensitivity and specificity.  相似文献   

9.
新发传染病主要是人畜共患病,是世界经济和公共健康的沉重负担。这就要求加强检测、鉴别和监视传染病的能力方面投入。高致病禽流感H5N1、新甲型流感("猪流感")H1N1、非典型性肺炎、西尼罗河病毒、地方流行性狂犬病、布鲁氏菌病以及发展中国家暴发的其它人畜共患病及近期猪抗甲氧西林金黄色葡萄球菌,是人类、动物及其环境相互作用的典型范例。面临中国动物和人类常见的新发传染病坚持"同一个健康"战略,这就要求业已存在的兽医和人医及公共卫生机构的通力合作。人的疾病控制系统与动物疾病控制系统虽然都已经建立,但人畜共患病的暴发表明兽医机构和人医机构密切合作的重要性。在保证环境健康的同时,通过动物疾病和人类疾病监测系统的密切合作,中国就一定能够控制人畜共患病。以这种方式进行疾病预防、监测与应对,各层面及各动物生产部门间有效的兽医推广是加强和保持健康生态环境中人和动物健康的有效办法。中国还需大量努力才能达到从制度上保证预防和消灭疾病。透明而准确的人与动物疾病监督通常会产生经济且可持续的预防疾病方法。加拿大在兽医、公共健康、食品安全和人畜共患病预防方面所发挥的作用就是与中国农业部合作,促进必要的、可持续的兽医监督网络的建设。  相似文献   

10.
Chronic inflammatory liver disease regardless of aetiology leads to failing regeneration and fibrosis, ending in cirrhosis. Both in man and in animals this worldwide health problem has no definitive cure. Chronic liver injury causes hepatic stellate cells to proliferate and differentiate into matrix-producing cells. New therapeutic options will be developed upon detailed understanding of the molecular mechanisms driving liver fibrosis. This may lead to new anti-fibrotic therapies which need to be tested in suitable models before application in the veterinary and human clinic. On the other side, to restore the failing regenerative capacity of the diseased liver cells, adult progenitor cells are of interest, as an alternative to whole organ transplantation. In order to find the most suitable large animal model it is important to recognise that the typical histopathological reaction pattern of the liver can differ between mammalian species. It is therefore imperative that specialists in veterinary internal medicine and pathology, being familiar with the diseases and pathologies of the liver in different animal species, are teaming-up in finding the best models for veterinary and human liver diseases. Several large animal models have been mentioned, like pigs, sheep, and dogs. Based on the observations that man and dog share the same hepatopathies and have identical clinical, pathological and pathogenetic reaction patterns during the development of liver disease, the dog seems to be a properly suited species to test new therapeutic strategies for pets and their best friends.  相似文献   

11.
Primary pulmonary carcinomas are being encountered with increasing frequency in older dogs and cats. The most common presenting complaint in the canine is a nonproductive cough of several weeks' duration, but many affected animals have no abnormal clinical signs in the early stages of the disease. A solitary mass that arises from a single focus in the peripheral pulmonary tissue is the most frequently observed radiographic sign of a primary lung tumor. Often a definitive diagnosis can be made only following thoracotomy with removal or biopsy study of the neoplastic tissue. A classification system based on the prevailing histologic pattern may then be used to categorize most primary lung neoplasms as adenocarcinomas, squamous cell carcinomas, anaplastic carcinomas, or bronchioloalveolar carcinomas. Adenocarcinomas are most common in the dog and cat. Only the neoplastic cell type and the presence or absence of metastatic disease have been found to be of value as prognostic indicators. Following wide surgical resection of the pulmonary mass, dogs with pulmonary adenocarcinomas are reported to have a longer mean survival time than animals with other types of primary lung carcinomas.  相似文献   

12.
输血疗法能够帮助患病牲畜迅速清除体内相关致病因子,因此从治疗疾病的目的来看,该方法是一种非常迅速有效的治疗措施。同理,把输血疗法应用到牛病的治疗环节中能够在一定程度上提高牛病治疗的效果和意义。笔者在本文中对输血疗法应用于牛病治疗的方式、方法进行了简要分析,从供血牛以及配血实验的角度出发,对输血治疗的相关方法进行了阐述。笔者强调了输血疗法在牛病治疗领域的价值、作用和意义,希望所得出的方法能够帮助到相关从业人员以及牛类养殖户。  相似文献   

13.
A systematic approach to the diagnosis of disseminated lung disease is more accurate and comprehensive than one based on the memorization of the appearance of each disease. The patterns of disseminated diseases are based on the pathophysiological changes. They are: alveolar, interstitial, bronchial, vascular and mixed. Each pattern has its own characteristics and list of causes.
The alveolar pattern is the most common in small animals. Pathogenesis and radiographic characteristics of the pattern, and the ways in which diseases cause it, are described.
Differential diagnosis, using clinical and radiographic findings, is discussed.  相似文献   

14.
奶牛分娩后其生理代谢发生巨大变化,由于体能的消耗,其抗病力也相对较低,若产后护理不当容易出现代谢性疾病。本文通过实地走访、座谈方式对沂水县奶牛产后代谢病进行调查,对当地奶牛产后代谢疾病的发病率、易发牛群和发病症状进行总结,并从分娩时体能损耗、运动量、饲喂方式、营养搭配、应激和病理因素分析沂水县奶牛产后代谢病的发病原因,提出科学分娩与接产、适量运动、合理搭配日粮、定时定量饲喂、预防应激、做好产后护理等措施,促进奶牛产后体能和体质恢复,为减少产后代谢病发生提供参考依据。  相似文献   

15.
The precorneal tear film (PTF) is of critical importance in the physiologic and pathologic findings of the cornea. Clinicians should recall that quantitative and qualitative disorders of the PTF can be a cause of corneal diseases as well as a clinical sign of ocular surface diseases. It is also important to consider that some systemic and topical treatments may affect the PTF volume and composition. Not all interactions are known at this time. There is a continued need for basic research into PTF components in healthy and diseased equine eyes, because much remains unknown. Until additional basic information about the biochemical composition and pH of the PTF as well as the interactions between equine corneal pathogens and specific PTF deficits becomes available, it will not be possible to define the cause and effect relations precisely between the various ocular surface diseases and deficiencies,excesses, and imbalances of PTF components. It is quite possible that a number of equine corneal diseases may be manifestations of qualitative PTF disorders.  相似文献   

16.
This paper describes a method which enables the similarity of diseases based upon their physical sign frequencies to be defined relative to bovine spongiform encephalopathy (BSE). The means of the absolute differences between the sign frequencies of BSE and the differential diagnoses were used as measure of similarity. Four sets of signs were compared. The most useful quantitative measurement of difference between the diseases was achieved when only the variant signs were used. Diseases that have a high similarity to BSE when the variant signs are compared are more likely to have case presentations that approximate to those found in BSE. These are the diseases that are most likely to be confused with BSE by clinicians. Previously published BSE differential diagnoses from clinical opinion and brain histopathology are reported and compared to the diseases used in this study.  相似文献   

17.
魏勇  高嵩涓  曹卫东  段廷玉 《草地学报》2021,29(8):1605-1614
土传病害是制约我国农业可持续发展的因素之一。绿肥作为高效清洁的有机肥源,与主作物合理搭配,可有效降低主作物土传病害的发生和危害,是减少化学药剂使用的重要措施。因此,综述绿肥对土传病害的防控效果与机制,对于绿肥推广应用和土传病害绿色防控具有重要意义。绿肥影响作物土传病害的研究主要集中于土传真菌病害和线虫病害,且大多数研究表明,绿肥可通过增强主作物整体抗病水平,对病原菌的化感抑制作用和改善土壤理化性质,增加土壤微生物中拮抗菌多样性和丰富度等,显著降低主作物土传病害发病率和严重程度。然而,绿肥影响主作物病害的作用机制研究不够深入,绿肥-主作物搭配模式和绿肥调控主作物病害的社会经济学效益仍需探究。同时,加强绿肥-主作物病害一体化防控及绿肥与根际促生菌、生防菌等其他有机改良剂或与适当的化学防控措施之间协同作用的研究,是未来需要加强的研究方向。  相似文献   

18.
Digital venography is a contrast angiography technique used to study digital vascularity. The technique is simple to be carried out and can be performed under field conditions using a standard radiographic unit. The venogram examination is used to complement conventional radiographic examinations in animals affected by foot diseases. Discrepancy in the contrast vascular pattern may be observed before the clinical signs of the foot disease. Digital venography studies in ruminants are in smaller number than those in horses. The herein presented review discusses digital venography techniques used in ruminants as well as the differences and similarities between ruminants (cattle, sheep and goat) and horses.  相似文献   

19.
Induced pluripotent stem (iPS) cells derived from disease patients are an invaluable resource for biomedical research and may provide a source for replacement therapies. In this study, we have generated iPS cells from Asian patients with chronic degenerative diseases of the nervous system, including spinal muscular atrophy (SMA), Parkinson disease (PD) and amyotrophic lateral sclerosis (ALS) by transduction with four factors (KLF4, SOX2, OCT4 and c-MYC). All of the iPS cells showed pluripotency similar to that of human embryonic stem cells (hESCs) and were able to differentiate into various somatic cell types in vitro and in vivo. Furthermore, the iPS cells also can be committed to differentiate into neural cells, the cell type that is affected in chronic degenerative diseases. Therefore, the patient-specific iPS cells we generated offer a cellular model in which to investigate disease mechanisms, discover and test novel drugs and develop new therapies for chronic neurodegenerative diseases.  相似文献   

20.
Hind limb paresis or plegia in ferrets is a common sign of illness, which can be produced by intervertebral disc (IVD) extrusion or protrusion along with many other systemic diseases. This case report describes a ferret (Mustela putorius furo) with chronic onset paraplegia in which T7-T8, T8-T9, and T10-T11 IVD herniations and T9-T10 block vertebrae were diagnosed with the assistance of myelography. It is believed that the excessive stress on the adjacent annulus fibrosus and vertebral endplates resulting from block vertebrae could have been the cause of IVD disease in the atypical location described in this case.  相似文献   

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