Evidence-based medicine concepts.

Today, the busy clinician benefits from a philosophy of practice that brings together the best applicable evidence and the experiences of clinical work in an effort to provide the best care for individual patients. EBM provides a structured approach that recognizes the contributions of evidence and clinical experience. An EBM practice is efficient and effective in meeting the goal of assuring optimum care. The concepts of EBM make sense for veterinary medicine (even if there are limited numbers of randomized, blinded studies), and clinicians in all types of practice can apply them.     

Bayesian analysis of a mastitis control plan to investigate the influence of veterinary prior beliefs on clinical interpretation

The fundamental objective for health research is to determine whether changes should be made to clinical decisions. Decisions made by veterinary surgeons in the light of new research evidence are known to be influenced by their prior beliefs, especially their initial opinions about the plausibility of possible results. In this paper, clinical trial results for a bovine mastitis control plan were evaluated within a Bayesian context, to incorporate a community of prior distributions that represented a spectrum of clinical prior beliefs. The aim was to quantify the effect of veterinary surgeons’ initial viewpoints on the interpretation of the trial results.A Bayesian analysis was conducted using Markov chain Monte Carlo procedures. Stochastic models included a financial cost attributed to a change in clinical mastitis following implementation of the control plan. Prior distributions were incorporated that covered a realistic range of possible clinical viewpoints, including scepticism, enthusiasm and uncertainty. Posterior distributions revealed important differences in the financial gain that clinicians with different starting viewpoints would anticipate from the mastitis control plan, given the actual research results. For example, a severe sceptic would ascribe a probability of 0.50 for a return of <£5 per cow in an average herd that implemented the plan, whereas an enthusiast would ascribe this probability for a return of >£20 per cow. Simulations using increased trial sizes indicated that if the original study was four times as large, an initial sceptic would be more convinced about the efficacy of the control plan but would still anticipate less financial return than an initial enthusiast would anticipate after the original study. In conclusion, it is possible to estimate how clinicians’ prior beliefs influence their interpretation of research evidence. Further research on the extent to which different interpretations of evidence result in changes to clinical practice would be worthwhile.     

The information infrastructure that supports evidence-based veterinary medicine: a comparison with human medicine

In human medicine, the information infrastructure that supports the knowledge translation processes of exchange, synthesis, dissemination, and application of the best clinical intervention research has developed significantly in the past 15 years, facilitating the uptake of research evidence by clinicians as well as the practice of evidence-based medicine. Seven of the key elements of this improved information infrastructure are clinical trial registries, research reporting standards, systematic reviews, organizations that support the production of systematic reviews, the indexing of clinical intervention research in MEDLINE, clinical search filters for MEDLINE, and point-of-care decision support information resources. The objective of this paper is to describe why these elements are important for evidence-based medicine, the key developments and issues related to these seven information infrastructure elements in human medicine, how these 7 elements compare with the corresponding infrastructure elements in veterinary medicine, and how all of these factors affect the translation of clinical intervention research into clinical practice. A focused search of the Ovid MEDLINE database was conducted for English language journal literature published between 2000 and 2010. Two bibliographies were consulted and selected national and international Web sites were searched using Google. The literature reviewed indicates that the information infrastructure supporting evidence-based veterinary medicine practice in all of the 7 elements reviewed is significantly underdeveloped in relation to the corresponding information infrastructure in human medicine. This lack of development creates barriers to the timely translation of veterinary medicine research into clinical practice and also to the conduct of both primary clinical intervention research and synthesis research.     

母猪生产性能的常用临床研究方法比对分析

母猪是生猪养殖中关键的一个组成部分,对其生产性能进行临床研究可提高生产效率。结合循证医学知识以及生猪养殖状况,对常用的临床研究方法进行比对和分析,发现随机对照试验的证据等级高、可靠性好,但成本较高,适合于大型企业应用;队列研究证据可对疫苗药物的不良反应以及生产措施开展评价、证据等级较高,成本较低,值得广泛采用;病例对照研究成本低、时间短、容易被基层员工理解,但易产生偏倚,证据等级较低;横断面研究常与统计盘点相结合、应用较广泛,但因果关系可靠性差;病例报告容易操作,对员工文化水平要求低,可应用于基层部门的经验交流,并其具有高度选择性,但推广价值较低。     

Management of chronic airway inflammation in the horse: A systematic review

The purpose of this article is to review available scientific reports on recurrent airway obstruction and inflammatory airway disease treatment efficacy. Critical evaluation of the quality and limitations of the evidence provided should provide equine practitioners with the tools to apply the latest scientific data to the management of individual clinical cases. While a large body of clinical research supports the efficacy of low‐dust environmental management and corticosteroid administration in the treatment of recurrent airway obstruction, limited clinical trials exist to evaluate the treatment of inflammatory airway disease.     

Emesis in dogs: a review

Emesis is a common presenting sign in small animal practice. It requires a rational approach to management that is based upon a sound understanding of pathophysiology combined with logical decision making. This review, which assesses the weight of available evidence, outlines the physiology of the vomiting reflex, causes of emesis, the consequences of emesis and the approach to clinical management of the vomiting dog. The applicability of diagnostic testing modalities and the merit of traditional approaches to management, such as dietary changes, are discussed. The role and usefulness of both traditional and novel anti-emetic drugs is examined, including in specific circumstances such as following cytotoxic drug treatment. The review also examines areas in which common clinical practice is not necessarily supported by objective evidence and, as such, highlights questions worthy of further clinical research.     

芦荟叶主要化学成分及其功效的研究进展

笔者综述了芦荟叶的化学成分及功效的研究成果,并从化学成分类型、药理作用、临床应用等方面阐述了该研究的进展情况.芦荟叶主要含有蒽醌类、糖类、氨基酸、有机酸、矿物质与微量元素、活性酶、维生素等多种化学成分,其中蒽醌类化合物为主要活性成分.芦荟叶具有美容、保健、抑菌、降血脂、抗肿瘤、防老化等作用.芦荟叶有进一步开发的药用价值.     

Principles and Practice of Therapeutic Exercise for Horses

Physical therapists are an integral component of the medical team in human health care. They are backed by a solid foundation of basic science and clinical research. Veterinarians have only recently begun to incorporate physical therapy into clinical practice, but without formal research that validates therapeutic interventions specific to equine patients. The purpose of this article is to present a series of therapeutic exercises adapted for horses based on knowledge and experience of human physical therapy, equine biomechanics, and the types of movement dysfunction commonly seen in the performance horse. Injuries, lameness and musculoskeletal pain syndromes, frequently encountered in equine practice, are disorders that may be successfully addressed with physical therapy. Incorporating standard therapeutic interventions based on clinical success in humans, basic science research, or expert opinion is possible with the understanding that these techniques will ultimately be accepted or refuted when their success or failure is formally documented. This review is designed to stimulate discussion and encourage research that will add to the knowledge base and lead to effective therapeutic protocols in the equine patient.     

Conduct,Oversight, and Ethical Considerations of Clinical Trials in Companion Animals with Cancer: Report of a Workshop on Best Practice Recommendations

Development of effective and safe treatments for companion animals with cancer requires the collaboration of numerous animal health professionals and the full engagement of animal owners. Establishing ‘Best Practice Recommendations’ for clinical trials in veterinary oncology represents an important step toward meeting the goal of rigorous clinical trial design and conduct that is required to establish valid evidence. Likewise, optimizing patient welfare and owner education and advocacy is crucial to meet the unique ethical obligations to both owners and animals enrolled in these clinical trials and to ensure trust in the team conducting the research. To date, ‘Best Practice Recommendations’ for clinical trial conduct have not been reported for veterinary oncology. This document summarizes the consensus of a workshop held in November, 2014 to identify relevant ethical principles and to ensure responsible conduct of clinical research in companion animals with cancer. It is intended as a working document that will be updated as advances in science and ethical considerations require. To the extent possible, existing guidelines for the conduct and oversight of clinical trials in humans have been adapted for veterinary trials to avoid duplicative effort and to facilitate integration of clinical trials such that translational research with benefits for both companion animals and humans are encouraged.     

New perspectives on the development of extrahepatic portosystemic shunts

In this essay we use clinical evidence and knowledge of anatomy to examine the relationship between blood flow and formation of congenital extrahepatic portosystemic shunts in dogs and cats. First we report on the clinical findings in a series of 50 dogs and 10 cats and then systematically review peer‐reviewed data on the detailed anatomy of shunts in dogs and cats. In dogs four types of shunt: spleno‐caval, left gastro‐phrenic, left gastro‐azygos and those involving the right gastric vein account for 94% of extrahepatic shunts. Cats also exhibit four types of shunt: spleno‐caval, left gastrophrenic, left gastro‐caval and left gastro‐azygos, and the first three of these account for 92% shunts in this species. Our findings lead us to propose that preferential blood flow influences the subsequent formation of one of a number of defined and consistent congenital extrahepatic portosystemic shunts in dogs and cats.     

Evidence-Based Treatment for Laminitis-What Works?

Acute or recurrent laminitis often results in marked structural or mechanical disruption of the hoof with rotation or sinkage of the coffin bone within the hoof capsule in affected horses or those predisposed to developing this complex and devastating disease. A complete knowledge and understanding of laminitis and its complex pathophysiologic cascade remains elusive despite the substantial time and effort that many scientists and clinicians have dedicated over the last few decades. As a result, preventive and therapeutic management strategies remain empirical and anecdotal, with little emphasis on evidence-based medicine. Evidence-based medicine involves integrating individual clinical expertise with external clinical evidence from systematic research to make the best possible decisions regarding patient management. Numerous and overlapping theories have been postulated for the pathophysiology of laminitis. Although beyond the scope of this discussion, the current most commonly discussed theories include vascular or ischemic, inflammatory, metabolic, enzymatic, and biomechanical. In reality, many of these pathways or others yet to be identified are likely involved in the complex cascade of acute laminitis. Substantial focused and relevant research is needed to advance our knowledge and understanding of this complex disease and to develop more effective preventive and therapeutic strategies based on sound scientific and clinical evidence.     

兽医科学研究中的样品采集方法及其最新进展

样品采集是兽医科学研究中必不可少的环节。以中华人民共和国农业行业标准《动物疫病实验室检验采样方法》为基础,结合临床实践和研究经历,介绍了基于不同研究目的和内容的样品采集种类、数量和操作,以及样品收装、保存和处理方法,重点概述了国内外关于采样方法的最新进展,从而为今后的兽医科学研究提供参考。     

两种一步法RNA提取试剂的比较

RNA的提取在生物医学研究和临床检测上应用广泛。本文分别用进口Invitrogen公司生产的以及我们自己研制的一步法RNA提取试剂，提取大肠杆菌RNA、鸡肌肉组织RNA和尿囊液RNA，通过核酸电泳和荧光定量RT-PCR进行比较。结果表明用我们自己研制的和进口的试剂提取的RNA都不含有DNA；这些RNA都可以作为模板进行RT-PCR检测，并且在数量上相互之间没有明显差异。说明我们自己研制的一步法RNA提取试剂可以取代进口试剂。此外，本文还讨论了此类试剂一些评定方法。     

A practical technique for preparation of antiserum to canine factor VIII-related antigen

Identification and measurement of canine factor VIII-related antigen (VIIIR:Ag) has many clinical and research applications, including differential diagnosis of hemophilia A and von Willebrand's disease, use as a marker for specific cell types, and elucidation of the structure of this factor VIII component. We have developed a practical method for producing antibodies to canine VIIIR:Ag that uses 2% agarose filtration for purification and identifies the antigen by correlation with the elution of the peak A280 fraction in the void volume. Antisera for electroimmunoassay (EIA) can be produced in less than four weeks from simple starting materials and with commonly available laboratory equipment. This technique would be useful for either clinical veterinary or comparative research laboratories.     

Conditions associated with canine hypothyroidism.

Careful review of the literature regarding clinical signs caused by hypothyroidism in dogs has shown that some assumptions regarding the relation of hypothyroidism to other conditions are based on anecdotal evidence. Cutaneous manifestations are present in most hypothyroid dogs, but the specific abnormalities and breed variations remain to be clearly defined. Decreased metabolic rate manifested by obesity and lethargy is also common. Neurologic manifestations, although uncommon, clearly occur in hypothyroid dogs. Cardiac abnormalities seem to be common, but their clinical significance is questionable. The only consistent hematologic abnormality that occurs in hypothyroid dogs is anemia; evidence for acquired von Willebrand's disease or other bleeding disorders is negligible. Reproductive dysfunction secondary to hypothyroidism is unlikely to occur in male dogs, and there is no evidence to support abnormalities in female dogs. The relation of megaesophagus, laryngeal paralysis, ocular abnormalities, and gastrointestinal disorders with hypothyroidism remains to be established. Future research into canine hypothyroidism may serve to convert dogma into a more clear understanding of the manifestations and pathophysiologic findings of this common endocrinopathy.     

The ACVD task force on canine atopic dermatitis (XXIV): allergen-specific immunotherapy.

Allergen-specific immunotherapy (ASIT) has been used for years to treat dogs with atopic dermatitis (AD) and humans with atopic diseases. The efficacy of ASIT has been well documented for humans with respiratory atopic diseases and stinging insect allergy, but its effectiveness seems more controversial for patients with AD. In spite of insufficient evidence derived from randomized controlled trials, multiple open studies and a large body of clinical observations suggest that ASIT is effective in controlling the clinical signs of dogs with AD. As a result of the scarcity of evidence from controlled trials, the true efficacy of ASIT, and the optimal protocols for allergen dose and frequency of injection are currently unknown. Allergen-specific immunotherapy nevertheless may be included in the treatment of canine AD because of its potential advantages and limited disadvantages compared to other forms of therapy. There is no evidence, however, for the preference of any specific treatment protocol. The predictive value of historical, clinical and immunologic features related to the efficacy of ASIT in dogs with AD are discussed in this paper. Adverse reactions, and the requirements for monitoring of patients receiving ASIT, then are reviewed and detailed. Finally, this review highlights aspects of ASIT where further research and controlled studies are needed.     

Feline Temporal Lobe Epilepsy: Review of the Experimental Literature

Accumulating evidence suggests that epileptic seizures originating from the temporal lobe (TL) occur in cats. Typically, affected animals have clinically focal seizures with orofacial automatisms including salivation, facial twitching, lip smacking, chewing, licking, and swallowing. Motor arrest and autonomic and behavioral signs also may occur. Many affected cats have magnetic resonance imaging (MRI) changes within the hippocampus or histopathologically confirmed hippocampal sclerosis or necrosis. From the 1950s to the 1980s, cats frequently were used as animal models for neurophysiological experiments and electrophysiological studies, from which important basic knowledge about epilepsy originated, but which has been rarely cited in clinical veterinary studies. These studies were reviewed. Experimental research on cats showed the widespread anatomical connections among TL structures. The ictal clinical signs originating from the hippocampus, amygdala, or lateral temporal cortex are similar, because of their dense interconnections. The ictal signs can be divided into autonomic, somatic, and behavioral. For research purposes, a 6‐stage system was established, reflecting the usual sequential progression from focal to generalized seizure: attention response (1), arrest (2), salivation, licking (3), facial twitching (4), head turning or nodding (5), and generalized clonic convulsions (6). Knowledge of this data may help in recognizing low‐stage (stage 1 or stage 2) epileptic seizures in clinical practice. Early experimental research data are in accordance with recent clinical observations regarding ictal clinical signs of TL epileptic seizures in cats. Furthermore, the research data supports the idea that TL epilepsy represents a unique clinical entity with a specific seizure type and origin in cats.     

伞形科参棕亚科及牵环花亚科气孔的结构及其分类学价值

本文首次深入研究了伞形科参棕亚科和牵环花亚科及相关类群34属(参棕亚科9属,牵环花亚科21属)48种植物叶片(茎或果实)的气孔结构,结果显示有3种类型气孔:无规则型,不等型及平列型。参棕亚科的气孔多为平列型,少为无规则型,而牵环花亚科多为无规则型,少为不等型(Gymnophyton除外)。Bowlesia分支的细胞壁多为深波状,其他分支的细胞壁多平直。气孔结构的研究为分子系统学建立的参棕亚科和牵环花亚科,以及Bowlesia分支提供了形态学依据,并支持分子系统学将Apiopetalum,Mackinlaya及Stilbocarpa从五加科分别移入参棕亚科和牵环花亚科,将Homalosciadium,Platysace,Hermas及Klotzschia移出两亚科。     

提高动物繁殖力的核酸疫苗研究进展

核酸疫苗也叫基因疫苗或DNA疫苗,是20世纪90年代初开发的一种新疫苗,具有稳定、安全、制备简单等优点.近年来,大量研究表明,利用核酸疫苗免疫可以有效提高动物的繁殖力,其中有些疫苗已经进入临床应用实验阶段.本文对提高动物繁殖性能的核酸疫苗的种类、作用原理及其在实验动物、家畜等多种动物上的应用研究进行了综述,以期为进一步...     

Feline blood transfusions: A pinker shade of pale

PRACTICAL RELEVANCE: blood transfusions are a potentially life-saving procedure that are within the reach of most small animal practitioners. Only minimal equipment is required. PATIENT GROUP: any cat with clinical signs attributable to a reduced red blood cell mass that is affecting oxygen transport (as a result of reduced packed cell volume or acute blood loss) is a potential candidate for a transfusion. CLINICAL CHALLENGES: although the principles of transfusion medicine are not complicated, there can be fatal consequences if certain steps are omitted. DIAGNOSTICS: blood typing kits and blood filters are readily available from veterinary wholesalers, laboratories and blood banking services. EVIDENCE BASE: over the past three decades, a substantial body of clinical research and reports has built up covering feline blood types and transfusion medicine. This article draws on that research to provide clinical guidance aimed at all veterinarians in feline or small animal practice who either currently practise transfusion medicine or plan to do so.