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841.
Over the last 35 years there has been extensive research into human wounds and consequent evolutionary changes in their management. Products such as vapour-permeable films, alginates, hydro-colloids, hydrogels and foams have been developed, all of which contribute in different ways to the enhance-ment of the healing cascade. The first part of this study assessed the influence on animal wound healing of some of these contemporary wound-management products
  With animal wounds the major problem is their isolation from the aggression of both the patient and the environment. The second part of this paper is directed at the development of an occlusive chamber to enable topically applied medicaments to remain in contact with the wound surface and presents the initial results of a programme of investigation directed at producing a 'ring' adhesive to overcome the adherence problems presented by lipid concentration and hirsutism. This adhesive also allows successive applications of contemporary dressings.  相似文献   
842.
谷氨酰胺对水生动物免疫的影响及机理   总被引:1,自引:0,他引:1  
本文主要围绕谷氨酰胺对水生动物免疫的影响及机理进行综述,旨在促进谷氨酰胺在水生动物上的研究及科学应用。  相似文献   
843.
近年来,中国水产养殖业高速发展,水产动物投喂策略逐渐受到重视。列举与分析了一系列国内外水产动物饲料投喂策略的相关研究内容,并进行了较为系统的整理与总结。投喂策略是现代集约化水产养殖生产过程中重要的生产管理要素,其技术内涵可简要概括为投喂频率、投喂率和投喂作业方式等,不同的水产动物种类以及不同的生长阶段所需的适宜养殖投喂策略亦不相同。叙述了投喂策略对养殖动物生长性能、消化代谢能力、应激免疫水平、行为响应以及存活率等影响,为水产动物饲料投喂策略的选择和相关技术理论的研究提供参考。  相似文献   
844.
Macrolide-resistant Streptococcus pyogenes is an emerging problem with a great public health concern throughout the world. The current study was carried out in order to investigate the possible role of pet animals in the epidemiology of such pathogen. For this purpose, nasal or oral swabs were collected from 115 pets (40 dogs and 75 cats) with respiratory illness. The collected swabs were cultured for isolation and identification of S. pyogenes. Macrolide-resistant S. pyogenes strains were initially identified after antibiotic susceptibility testing of the all obtained S. pyogenes isolates, then the phenotypic and molecular identification were done using the double-disk test and the detection of macrolide resistance genes, respectively. Of the 115 examined pet animals, S. pyogenes was recovered from 11 (9.6 %), from which, the isolation rates among dogs and cats were 15 % and 6.7 %, respectively. Macrolide-resistant S. pyogenes was isolated from dogs and cats in the following rates 10 % and 5.3 %, respectively. All macrolide-resistant S. pyogenes strains were assigned to cMLS resistance phenotype while all of them carried ermB gene only, except one strain from a cat possessed both ermB and ermTR genes. The phylogenetic analysis of 4 ermB gene sequences showed high genetic relatedness with those carried by bacteria isolated from human cases to underline the public health impact of such strains. Seriously, all macrolide-resistant S. pyogenes strains were resistant to penicillin. The emergence of penicillin-macrolide resistant S. pyogenes among pet animals underscores not only an emerging veterinary pathogen, but also an ongoing public health threat.  相似文献   
845.
ObjectiveThis article examines the ethical principles underlying the Declaration of Helsinki as an internationally agreed justificatory framework for human medical research. The aim of the analysis is to consider the potential usefulness of these principles for defining an internationally agreed ethical 'best practice' in clinical veterinary research (CVR). It is suggested that the specific ethical responsibilities of the clinician to protect the interests of their patient when conducting medical research may be translated into the veterinary setting. Through exploring risk and harm, unproven interventions, vulnerability and informed consent, the article identifies the ethical risks of CVR. It is shown that veterinary regulators in the UK and the European Union have addressed these concerns to varying degrees; however, disagreements over the appropriateness of specific CVR practices are identified. A commitment to collaborative exploration of the benefits and challenges of implementing a Declaration of Helsinki for Animals is proposed.  相似文献   
846.
Unmanned aerial vehicle (UAV) technology, artificial intelligence, and the relevant hardware can be used for monitoring wild animals. However, existing methods have several limitations. Therefore, this study explored the monitoring and protection of Amur tigers and their main prey species using images from UAVs by optimizing the algorithm models with respect to accuracy, model size, recognition speed, and elimination of environmental interference. Thermal imaging data were collected from 2000 pictures with a thermal imaging lens on a DJI M300RTK UAV at the Hanma National Nature Reserve in the Greater Khingan Mountains in Inner Mongolia, Wangqing National Nature Reserve in Jilin Province, and Siberian Tiger Park in Heilongjiang Province. The YOLO V5s algorithm was applied to recognize the animals in the pictures. The accuracy rate was 94.1%, and the size of the model weight (total weight of each model layer trained with the training set) was 14.8 MB. The authors improved the structures and parameters of the YOLO V5s algorithm. As a result, the recognition accuracy rate became 96%, and the model weight was 9.3 MB. The accuracy rate increased by 1.9%, the model weight decreased by 37.2% from 14.8 MB to 9.3 MB, and the recognition time of a single picture was shortened by 34.4% from 0.032 to 0.021 s. This not only increases the recognition accuracy but also effectively lowers the hardware requirements that the algorithm relies on, which provides a lightweight fast recognition method for UAV-based edge computing and online investigation of wild animals.  相似文献   
847.
Pyrethrin and pyrethroid insecticides are widely used in veterinary medicine for agricultural and domestic purposes. Although pyrethrins and pyrethroids are generally regarded as safe to animals, there have been reports of systemic poisoning in veterinary species. This review summarises the use of pyrethrins and pyrethroids in companion and food producing animals, including their mechanism of action and toxicity. The toxicokinetics of pyrethrins and pyrethroids are described, including absorption, distribution, metabolism (including interactions with other compounds affecting drug metabolising enzymes) and excretion, leading to the application of toxicokinetic/toxicodynamic concepts. Specific cases of pyrethroid poisoning in laboratory animals (including age-related toxicity), fish, companion and large animals are considered, including the high incidence of feline pyrethroids toxicosis following the extra-label use of topical formulations.  相似文献   
848.
代谢组学是一门新兴的学科,与基因组学、蛋白质组学等共同构成系统生物学。近年来,代谢组学发展迅速,并在疾病诊断、生物医药研发、食品营养与科学、药理毒理学、环境科学、植物科学以及动物育种等众多领域均有应用。系统介绍了动物育种中小分子代谢物在遗传参数估计、品种(系)鉴定、重要经济性状鉴定、多组学关联分析以及动物疾病模型制备中的应用及最新研究进展,分析代谢组学研究中存在的问题。随着其研究方法的不断完善和优化,越来越多代谢物被人们所了解认识,在农用动物育种中代谢组学技术的研究逐渐增多,代谢组学必将成为动物育种的一种有力手段。  相似文献   
849.
Applications for acute phase reactants (APRs) in nondomesticated mammals include identifying inflammatory disease, monitoring the course of specific disease processes and recovery during rehabilitation, detecting preclinical or subclinical disease, being used as bioindicators for monitoring population and ecosystem health, and as markers of stress and animal welfare. Serum amyloid A, haptoglobin, C-reactive protein, fibrinogen, albumin, and iron are most commonly measured. The procedure for evaluating an APR in a nondomesticated mammalian species should follow a stepwise approach beginning with an assessment of analytical performance, followed by an evaluation of overlap performance, clinical performance, and impact on patient outcomes and management. The lack of species-specific standards and antibodies for nondomesticated mammals presents a challenge, and more attention needs to be focused on assessing cross-reactivity and ensuring adequate analytical performance of APR assays. Sample selection for the initial evaluation of APRs should consider preanalytical influences and should originate from animals with confirmed inflammatory disease and healthy animals. Reference intervals should be generated according to published guidelines. Further evaluation should focus on assessing the diagnostic utility of APRs in specific disease scenarios relevant to a species. Greater attention should be paid to assay performance and uniformity of methods when using APRs for population and ecosystem surveillance. Veterinary clinical pathologists should work closely with zoo veterinarians and wildlife researchers to optimize the accuracy and utility of APR measurements in these various conservation medicine scenarios.  相似文献   
850.
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