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21.
OBJECTIVES: To assess the diagnostic yield of a routine fecal panel and determine whether Clostridium perfringens or C difficile toxin production is associated with acute hemorrhagic diarrheal syndrome (AHDS) in dogs. DESIGN: Case-control study. ANIMALS: 260 dogs with diarrhea and 177 dogs with normal feces. PROCEDURE: Medical records were reviewed for results of culture for C difficile, Campylobacterspp, and Salmonella spp; C perfringens fecal enterotoxin (CPE) assay via ELISA or reverse passive latex agglutination (RPLA) assay; fecal endospore enumeration; C difficile toxin A assay; and parasite evaluation. RESULTS: Prevalence of CPE in dogs with diarrhea was 22/154 (14.3%) via ELISA and 47/104 (45.2%) via RPLA assay, versus 9/74 (12%) via ELISA and 26/103 (25%) via RPLA assay in control dogs. Prevalence of C difficile was 47/260 (18%) in dogs with diarrhea and 41/74 (55%) in control dogs. Prevalence of C difficile toxin A was 26/254 (10.2%) in dogs with diarrhea and 0/74 in control dogs. Diagnosis of AHDS was made in 27 dogs; 8 had positive results for CPE, 7 had positive results for toxin A, and 1 had positive results for both toxins. Campylobacter spp were isolated from 13 of 260 (5%) dogs with diarrhea and 21 of 74 (28.4%) control dogs. Salmonella spp were isolated from 3 (1.2%) dogs with diarrhea. CONCLUSIONS AND CLINICAL RELEVANCE: Diagnostic value of a fecal panel in dogs with diarrhea appears to below.  相似文献   
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The objective of this study was to understand influence of planting spacing on mechanical properties of Eucalyptus grandis × E. urophylla planted as a potential species for solid wood products in China. Four trees at age of 13 were selected from each of 6 groups of planting spacing and a total of 24 sampling trees were selected from the Dongmen Forestry Center of Guangxi Province in China. Furthermore, a one-meter-long log from each tree was cut into small blocks for wood properties testing. MOE, MOR and co...  相似文献   
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改良剂与植物协同作用治理污染土壤,结果表明:植物种类对土壤中硝态氮浓度的变化影响非常显著,种植小麦的土壤中硝态氮浓度均从692.19 mg/kg降至100 mg/kg以下;当沸石粒径1~2 mm,改良剂与土壤比例为3:50时,种植小麦的土壤中硝态氮浓度降至43 mg/kg。改良剂种类对土壤中铵态氮浓度的变化影响非常显著,当沸石粒径2~3mm,改良剂与土壤比例为10:50,改良第15天铵态氮浓度由23 593.75 mg/kg降至3 300mg/kg。改良剂、植物对土壤中硫酸根主要表现为解吸作用,改良剂种类对土壤中硫酸根浓度的变化影响非常显著,用石灰石改良剂改良土壤第7天,土壤中的铵态氮浓度由370 mg/kg至900 mg/kg。  相似文献   
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In this paper we describe novel methodology for evaluating competition among strains of Rhizobium bacteria which can be found naturally occurring in or can be introduced into soil. Rhizobia can occupy nodules on the roots of legume plants allowing the plant to ‘fix’ atmospheric nitrogen. Our model defines competitive outcomes for a community (the multinomial count of nodules occupied by each strain at the end of a time period) relative to the past state of the community (the proportion of each strain present at the beginning of the time period) and incorporates this prior information in the analysis. Our approach for assessing competition provides an analogy to multivariate methods for continuous responses in competition studies and an alternative to univariate methods for discrete responses that respects the multivariate nature of the data. It can also handle zero values in the multinomial response providing an alternative to compositional data analysis methods, which traditionally have not been able to facilitate zero values. The proposed experimental design is based on the simplex design and the model is an extension of multinomial baseline category logit models that includes multiple offsets and random terms to allow for correlation among clustered responses. Supplemental materials for this article are available from the journal website.  相似文献   
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When the concentration of calcium ions in the cerebral ventricles is elevated, a fully satiated rat eats voraciously. This feeding response is not prevented by prior intraventricular administration of alpha-or beta-adrenergic blocking agents, or other pharmacological antagonists. This supports the concept of an independent ionic mechanism, rather than a neurotransmitter one, for modulating a "set-point" for weight or hunger.  相似文献   
26.
A placenta is defined as structural approximation of maternal and foetal tissues to perform physiological exchange. Associated processes of differentiation and the establishment of its cells take place within the extracellular matrix (ECM) that provides a rich environment of collagens, fibronectins, cytokines and other components. Placental ECM is promising for tissue regeneration purposes, because it has immune tolerance capacities that may cause only minimal rejections of transplants with immunological differences between donor and recipient. However, specific characteristics of ECM during evolution of the structurally very diverse mammalian placenta are not yet revealed. We here address the major aspects of placental types, that is non‐invasive (epitheliochorial), medium (endotheliochorial)‐to‐high (haemochorial) invasive nature of the interhemal barrier between the foetal and maternal blood system as well as their main components of ECM with special reference to species that are commonly used as animal models for human placentation and in the potential applications for regenerative medicine.  相似文献   
27.
Many researches describe the embryonic developmental features in domestic animals; however, in farm animals, they are scarce. Most farm animal studies are related to assisted reproduction and embryos transfer techniques. But, morphological features and size measure to estimate the age gestation are rarely reported in literature. Thus, in this study, we described the developmental changes in the bubaline (Bubalus bubali) concepts from 21 to 60 days of gestation. Our results revealed that buffalo embryos similar morphological characteristics similar to other mammalian species. Also, similarities between bovine and bubaline persist; except on foetal stages when buffalos have a faster development than bovine. Therefore, buffalo's gestation period exhibits some varieties and accurate embryo age is more difficult. Yet, when we use a combination of the crown–rump, macroscopic analysis and alizarin red, it is possible to describe better the whole embryogenesis stages of the buffalo and which can contribute for future reproduction researches and applications in veterinary practice.  相似文献   
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The present communication is concerned with the effect of treatment with anthelmintics on animal performance in a system of beef production which was designed to make maximum use of grass and grass products. In the system under investigation a Leader/Follower system of grzing (i.e. Grazing calves in front of older cattle in the rotation) is adopted with conserved and grazing areas alternating during the season.Calves dosed with either levamisole or fenbendazole at time of change to aftergrass in mid-June performed significantly better than undosed controls. As judged by changes in serum persinogen levels (and liveweight gains in 1 year), dosing calces with fenbendazole at the end of the first grazing season was effective in removing inhibited larvae of Ostertagia ostertagi. Significant differences were found in both carcase weight and killing out percentage in the fenbendazole treated group.  相似文献   
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