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1.
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.  相似文献   
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新造林中防火隔离带分为天然防火隔离带;植物防火隔离带;防火林道,人工防火线等4种。在具体布设上则分为林中防火、林线防火、山脊防火、境界防火、铁路沿线、林区房屋隔离带6种。  相似文献   
3.
Pretreatment of somatic cells with undifferentiated cell extracts, such as embryonic stem cells and mammalian oocytes, is an attractive alternative method for reprogramming control. The properties of induced pluripotent stem cells (iPSCs) are similar to those of embryonic stem cells; however, no studies have reported somatic cell nuclear reprogramming using iPSC extracts. Therefore, this study aimed to evaluate the effects of porcine iPSC extracts treatment on porcine ear fibroblasts and early development of porcine cloned embryos produced from porcine ear skin fibroblasts pretreated with the porcine iPSC extracts. The ChariotTM reagent system was used to deliver the iPSC extracts into cultured porcine ear skin fibroblasts. The iPSC extracts-treated cells (iPSC-treated cells) were cultured for 3 days and used for analyzing histone modification and somatic cell nuclear transfer. Compared to the results for nontreated cells, the trimethylation status of histone H3 lysine residue 9 (H3K9) in the iPSC-treated cells significantly decreased. The expression of Jmjd2b, the H3K9 trimethylation-specific demethylase gene, significantly increased in the iPSC-treated cells; conversely, the expression of the proapoptotic genes, Bax and p53, significantly decreased. When the iPSC-treated cells were transferred into enucleated porcine oocytes, no differences were observed in blastocyst development and total cell number in blastocysts compared with the results for control cells. However, H3K9 trimethylation of pronuclear-stage-cloned embryos significantly decreased in the iPSC-treated cells. Additionally, Bax and p53 gene expression in the blastocysts was significantly lower in iPSC-treated cells than in control cells. To our knowledge, this study is the first to show that an extracts of porcine iPSCs can affect histone modification and gene expression in porcine ear skin fibroblasts and cloned embryos.  相似文献   
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The objective of this study was to describe the histopathologic changes observed in extrapituitary organs as well as the pituitary glands of horses with pituitary pars intermedia dysfunction (PPID). Adrenal gland, thyroid gland, liver, lung, kidney, heart, and pituitary gland from 32 horses with clinical and histologic evidence of PPID and 20 control horses were reviewed histologically. Ten of the control horses were aged animals (≥15 years), allowing those changes attributed to age to be identified. In addition to previously reported changes in adrenal gland and liver, an association was established between PPID and several extrapituitary histopathologic changes, namely bronchiolitis, proliferative glomerulopathy, and myocardial lipofuscinosis and fibrosis. The potential biologic significance of these changes is discussed and, although the retrospective design of the current study precludes establishment of causal relationships between the observed extrapituitary changes and PPID, these findings suggest that further investigations are warranted.  相似文献   
6.
Influence of dopamine on rumino-reticular motility and rumination in sheep   总被引:1,自引:0,他引:1  
The effects of intracerebroventricular (i.c.v.) and intravenous (i.v.) administration of dopamine and its antagonists (domperidone and metoclopramide) on forestomach motility were investigated in four sheep fitted with Nichrome electrodes and strain gauges implanted on the reticulum and the caudo-dorsal sac of the rumen. Infused by the i.c.v. route at a rate of 2 micrograms . kg-1 . min-1, dopamine inhibited the phasic contractions of the reticulo-rumen. A similar effect was obtained following i.v. administration of doses which were 10 times higher, but the effect was associated with an increased tone of the rumen wall. Prior i.v. administration of domperidone (0.5 micrograms . kg-1) blocked these effects and a selective blockade of the dopamine-induced inhibition of phasic contractions was obtained with higher dose of domperidone (2.5 micrograms . kg-1) administered centrally. When dopamine was infused alone ventricularly or intravenously after metoclopramide (40 micrograms . kg-1), it induced a transient (6-8 min) period of rumination, which could be blocked by a prior i.c.v. administration of tolazoline. It was concluded that dopamine acts on rumino-reticular motility in sheep through specific dopamine receptors (i) centrally by inhibiting the frequency of reticular contraction and (ii) peripherally by increasing the muscular tone of the rumen, and its effects on rumination involved alpha 2 adrenergic receptors located in the central nervous system.  相似文献   
7.
Pituitary neoplasm was identified in 43 dogs with pituitary-dependent hyperadrenocorticism via necropsy (n = 33), diagnostic imaging with computerized tomography or magnetic resonance imaging (n = 5), or diagnostic imaging and necropsy (n = 5). All dogs had clinical signs and clinicopathologic test results typical of hyperadrenocorticism. Thirty-seven dogs had grossly visible pituitary tumors, and 6 dogs had microscopic pituitary tumors. Fifteen dogs had developed neurologic signs typical of those resulting from an enlarging pituitary mass. Twenty-three dogs had pituitary tumors greater than or equal to 1 cm in diameter. Provocative testing of the pituitary-adrenocortical axis was performed on all dogs. Dogs with grossly visible pituitary tumors and dogs with neurologic signs had significantly (P less than 0.05) higher mean plasma endogenous ACTH concentrations, compared with values from dogs with microscopic tumors and dogs without neurologic signs, respectively. Dogs with grossly visible pituitary tumors and dogs with tumors greater than or equal to 1 cm in diameter had significantly (P less than 0.05) lower adrenocortical responsiveness to exogenous ACTH, compared with dogs with microscopic pituitary tumors and dogs with tumors less than 1 cm in diameter, respectively. Despite these differences, there was overlap between test results among dogs. On the basis of endocrine test results, it would appear difficult to distinguish dogs with pituitary-dependent hyperadrenocorticism and large pituitary tumors from those with pituitary-dependent hyperadrenocorticism and microscopic pituitary tumors prior to onset of neurologic signs.  相似文献   
8.
Outbreaks of a chronic branchitis in channel catfish Ictalurus punctatus (Rafinesque) were observed on four fish farms throughout the state of California from November 1982 to April 1984. Severe granulomatous inflammation of the gill filaments with necrosis of the cartilage of the gill ray and diffuse epithelial hyperplasia, resulting in extensive fusion of gill lamellae, was present on histologic examination of gill specimens from 35 out of 44 fish examined. Numerous, small trophozoites morphologically consistent with presporogonic myxosporean parasites were consistently associated with the inflammatory process. Mature spores of Henneguya exilis Kudo were present in large numbers in gill specimens from two fish and only occasionally in 22 others. Similar cases referred to as "Hamburger Gill Disease" or "proliferative gill disease" have been known to occur in the south-central United States. This report describes the morphologic changes of this condition and discusses its possible pathogenesis.  相似文献   
9.
A reducing solution of 2-mercaptoethanol and its oxidized form 2-hydroxyethyl disulfide, whose variable concentrations set variable disulfide reduction potentials, was applied to progressively reduce the disulfide bonds of proteins extracted from doughs made from Meneba and Robin Hood flour. Several dough proteins had disulfide bonds stronger than those of other dough proteins. A SDS-sedimentation method was applied to monitor the baking of dough into bread. Dough proteins susceptible to heat (baking) were studied by SDS-fractionation, extraction with reducing alcoholic solution, SDS-PAGE, and N-terminal protein sequencing. High or low molecular weight glutenins, α, β, and γ-gliadins, α-amylase inhibitor, and α-amylase trypsin inhibitor were identified among the dough proteins modified by heat (as shown by reduced solubility in aqueous-SDS solution). The heat-induced modification of the gliadins and glutenins might contribute to the coagulation of dough proteins, while the heat-induced modification of the amylase or trypsin inhibitors might contribute to the regulation of endogenous or exogenous amylolytic or proteolytic activities in dough or bread.  相似文献   
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