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691.
CASE DESCRIPTION-13 equids (10 horses, 2 donkeys, and 1 pony) were examined for signs of colic (n = 7), weight loss (6), anorexia (3), and diarrhea (2). Ten equids were evaluated in the fall (September to November). Seven equids had a history of persimmon ingestion. CLINICAL FINDINGS-A diagnosis of phytobezoar caused by persimmon ingestion was made for all equids. Eight equids had gastric persimmon phytobezoars; 5 had enteric persimmon phytobezoars. Gastroscopy or gastroduodenoscopy revealed evidence of persimmon ingestion in 8 of 10 equids in which these procedures were performed. TREATMENT AND OUTCOME-2 of 13 equids were euthanatized prior to treatment. Supportive care was instituted in 11 of 13 equids, including IV administration of fluids (n = 8) and treatment with antimicrobials (5), NSAIDs (5), and gastric acid suppressants (4). Persimmon phytobezoar-specific treatments included dietary modification to a pelleted feed (n = 8); oral or nasogastric administration of cola or diet cola (4), cellulase (2), or mineral oil (2); surgery (4); and intrapersimmon phytobezoar injections with acetylcysteine (1). Medical treatment in 5 of 7 equids resulted in resolution of gastric persimmon phytobezoars. Seven of 8 equids with gastric persimmon phytobezoars and 1 of 5 equids with enteric persimmon phytobezoars survived > 1 year after hospital discharge. CLINICAL RELEVANCE-Historical knowledge of persimmon ingestion in equids with gastrointestinal disease warrants gastroduodenoscopy for evaluation of the presence of persimmon phytobezoars. In equids with gastric persimmon phytobezoars, medical management (including administration of cola or diet cola and dietary modification to a pelleted feed) may allow for persimmon phytobezoar dissolution.  相似文献   
692.
Gene therapy approaches to the treatment of HIV infection have targeted both viral gene expression and the cellular factors that are essential for virus replication. However, significant concerns have been raised regarding the potential toxic effects of such therapies, the emergence of resistant viral variants and unforeseen biological consequences such as enhanced susceptibility to unrelated pathogens. Novel restriction factors formed by the fusion of the tripartite motif protein (TRIM5) and cyclophilin A (CypA), or "TRIMCyps", offer an effective antiviral defence strategy with a very low potential for toxicity. In order to investigate the potential therapeutic utility of TRIMCyps in gene therapy for AIDS, a synthetic fusion protein between feline TRIM5 and feline CypA was generated and transduced into cells susceptible to infection with feline immunodeficiency virus (FIV). The synthetic feline TRIMCyp was highly efficient at preventing infection with both HIV and FIV and the cells resisted productive infection with FIV from either the domestic cat or the puma. Feline TRIMCyp and FIV infection of the cat offers a unique opportunity to evaluate TRIMCyp-based approaches to genetic therapy for HIV infection and the treatment of AIDS.  相似文献   
693.
Ferrets have increased in popularity as pets, and a growing number are seen in companion animal practice. Domestic ferrets are commonly used as animal models for research of human oral conditions. The present study evaluated the prevalence of oral pathology in rescued ferrets which - to the authors' knowledge - has not yet been described in the scientific literature. Conscious oral examination was performed on 63 ferrets, of which 49 underwent general anesthesia for further examination. The most common clinical findings included malocclusion of mandibular second incisor teeth (95.2%); extrusion of canine teeth (93.7%); and abrasion and attrition of teeth (76.2%). Tooth fractures were exclusively associated with canine teeth and found in 31.7% of ferrets. Pulp exposure was confirmed in 60.0% of fractured teeth. The normal gingival sulcus depth measured < 0.5-mm in 87.8% of anesthetized ferrets. Clinical evidence of periodontal disease was present in 65.3% of anesthetized ferrets (gingivitis or probing depths > 0.5-mm), however advanced periodontal disease (i.e. periodontal pockets > 2-mm or stage 3 furcation exposure) was not found upon clinical examination. There was no evidence of tooth resorption, dental caries, stomatitis, or oral tumors in the examined group of ferrets.  相似文献   
694.
OBJECTIVE: To determine the effects of ketamine hydrochloride on hemodynamic and immunologic alterations associated with experimentally induced endotoxemia in dogs. ANIMALS: 9 mixed-breed dogs. PROCEDURES: In a crossover study, dogs were randomly allocated to receive ketamine (0.5 mg/kg, IV, followed by IV infusion at a rate of 0.12 mg/kg/h for 2.5 hours) or control solution (saline [0.9% NaCl] solution, 0.25 mL, IV, followed by IV infusion at a rate of 0.5 mL/h for 2.5 hours). Onset of infusion was time 0. At 30 minutes, lipopolysaccharide (LPS; 1 microg/kg, IV) was administered. Heart rate (HR), systolic arterial blood pressure (SAP), plasma tumor necrosis factor (TNF)-alpha activity, and a CBC were evaluated. RESULTS: Mean SAP was significantly reduced in dogs administered ketamine or saline solution at 2 and 2.5 hours, compared with values at time 0. However, there was no significant difference between treatments. At 1, 2, and 2.5 hours, dogs administered ketamine had a significantly lower HR than dogs administered saline solution. Although plasma TNF-alpha activity significantly increased, compared with values at time 0 for both groups, ketamine-treated dogs had significantly lower peak plasma TNF-alpha activity 1.5 hours after LPS administration. All dogs had significant leukopenia and neutropenia after LPS administration, with no differences detected between ketamine and saline solution treatments. CONCLUSIONS AND CLINICAL RELEVANCE: Administration of a subanesthetic dose of ketamine had immunomodulating effects in dogs with experimentally induced endotoxemia (namely, blunting of plasma TNF-alpha activity). However, it had little effect on hemodynamic stability and no effect on WBC counts.  相似文献   
695.

Context

Habitat complexity in rivers is linked to dynamic fluvial conditions acting at various spatial scales. On regulated rivers in the western United States, tributaries are regions of high energy and disturbance, providing important resource inputs for riparian ecosystems.

Objectives

This study investigated spatial patterns and extents of tributary influence on riparian habitat complexity in the near channel zone along regulated reaches of the Colorado (>?200 km) and Dolores Rivers (~?300 km) in the western United States. Because tributary confluences are regions of increased dynamism, we hypothesized that: (1) geomorphic and land cover complexity would be greatest close to tributary junctions and decrease with distance from tributaries; and (2) patterns in complexity would vary across different sized spatial units.

Methods

Using a combination of remote sensing and spatial analysis, we classified fluvial features and land cover classes to investigate patterns longitudinally at 10-, 25-, and 100-m spatial units in the near channel zone of two regulated rivers.

Results

Using change point analysis and randomization tests, we detected shifts in riparian habitat complexity closer to tributary junctions. Patterns varied across 10-, 25-, and 100-m spatial units in the near channel zone, with significance (p?≤?0.05) recorded for 10- and 25-m spatial units.

Conclusions

Tributary junctions deliver critical resource inputs on regulated systems, providing for increased geomorphic and land cover diversity upstream and downstream of tributaries. We found that patterns of response were non-linear and discontinuous, varying across spatial units and potentially influenced by the degree of mainstem flow regulation.
  相似文献   
696.
The goal of this prospective study was to determine the effect of hemoclip use on the size of radiation treatment fields based on a 3-cm margin around a surgical incision alone (field setup 1) vs. a 3-cm margin around the surgical incision plus hemoclips (field setup 2). Forty-seven dogs that underwent surgical resection of a total of 55 soft tissue masses had surgical hemoclips placed at the time of surgery and orthogonal radiographs made immediately postoperatively. Radiation treatment field simulation was done and field areas measured. Additional determinations included number of hemoclips outside of the radiation treatment field based on a margin around the incision alone, hemoclip distance from the incision, and association between incision length and greatest distance of hemoclips from the incision. There was a significant difference in radiation treatment field size using information regarding the location of hemoclips in conjunction with the surgical scar compared with the surgical scar alone for truncal (P = 0.0003) vs. extremity tumors (P = 0.087). In simulating radiation treatment fields hemoclips were located outside of field setup 1 for the majority of tumors (79%) resected from the trunk but only in a minority of tumors (10.7%) resected from extremity sites. The findings from this study suggest that surgical hemoclips have potential utility in simulation of radiation treatment fields in the postoperative setting.  相似文献   
697.
Sit., — We have recently been called upon to investigate an outbreak of respiratory disease amongst the occupants of a boarding cattery, which involved a number of apparently vaccinated cats.  相似文献   
698.
Plocamium cartilagineum is a common red alga on the benthos of Antarctica and can be a dominant understory species along the western Antarctic Peninsula. Algae from this region have been studied chemically, and like “P. cartilagineum” from other worldwide locations where it is common, it is rich in halogenated monoterpenes, some of which have been implicated as feeding deterrents toward sympatric algal predators. Secondary metabolites are highly variable in this alga, both qualitatively and quantitatively, leading us to probe individual plants to track the possible link of variability to genetic or other factors. Using cox1 and rbcL gene sequencing, we find that the Antarctic alga divides into two closely related phylogroups, but not species, each of which is further divided into one of five chemogroups. The chemogroups themselves, defined on the basis of Bray-Curtis similarity profiling of GC/QqQ chromatographic analyses, are largely site specific within a 10 km2 area. Thus, on the limited geographical range of this analysis, P. cartilagineum displays only modest genetic radiation, but its secondary metabolome was found to have experienced more extensive radiation. Such metabogenomic divergence demonstrated on the larger geographical scale of the Antarctic Peninsula, or perhaps even continent-wide, may contribute to the discovery of cryptic speciation.  相似文献   
699.
700.
Observational studies of cattle production systems usually find that cattle from conventional dairies harbor a higher prevalence of antimicrobial resistant (AMR) enteric bacteria compared to organic dairies or beef-cow operations; given that dairies usually use more antimicrobials, this result is not unexpected. Experimental studies have usually verified that application of antimicrobials leads to at least a transient expansion of AMR bacterial populations in treated cattle. Nevertheless, on dairy farms the majority of antibiotics are used to treat mastitis and yet AMR remains relatively low in mastitis pathogens. Other studies have shown no correlation between antimicrobial use and prevalence of AMR bacteria including documented cases where the prevalence of AMR bacteria is non-responsive to antimicrobial applications or remains relatively high in the absence of antimicrobial use or any other obvious selective pressures. Thus, there are multi-factorial events and pressures that influence AMR bacterial populations in cattle production systems. We introduce a heuristic model that illustrates how repeated antimicrobial selection pressure can increase the probability of genetic linkage between AMR genes and niche- or growth-specific fitness traits. This linkage allows persistence of AMR bacteria at the herd level because subpopulations of AMR bacteria are able to reside long-term within the host animals even in the absence of antimicrobial selection pressure. This model highlights the need for multiple approaches to manage herd health so that the total amount of antimicrobials is limited in a manner that meets animal welfare and public health needs while reducing costs for producers and consumers over the long-term.  相似文献   
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