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51.
Sequences representing the genomes of two distinct virus isolates infecting wild plants of two members of the genus Drakaea (hammer orchids) in Western Australia are described. The virus isolated from Drakaea livida has a bipartite genome of 4490 nt (RNA1) and 2905 nt (RNA2) that shares closest sequence and structural similarity to members of the genus Pecluvirus, family Virgaviridae, described from legumes in the Indian subcontinent and West Africa. However, it differs from pecluviruses by lacking a P39 protein on RNA2 and having a cysteine‐rich protein gene located 3′ of the triple gene block protein genes. It is the first peclu‐like virus to be described from Australia. The name Drakaea virus A is proposed (DVA; proposed member of the family Virgaviridae, genus unassigned). The second virus isolate was identified from Drakaea elastica, a species classed as endangered under conservation legislation. The genome sequence of this virus shares closest identity with isolates of Donkey orchid symptomless virus (DOSV; proposed member of the order Tymovirales, family and genus unassigned), a species described previously from wild Caladenia and Diuris orchids in the same region. These viruses are the first to be isolated from wild Drakaea populations and are proposed to have an ancient association with their orchid hosts.  相似文献   
52.
Osteochondromas in the horse are most commonly found as a solitary lesion affecting the distal radial metaphysis. In this location, diagnosis is reliant on radiographic and ultrasonographic examination and confirmed with post-operative histopathology. This case report describes the additional benefit of performing a CT arthrogram to aid the diagnosis of an osteochondroma in an atypical location.  相似文献   
53.
ObjectiveTo compare the quality of postoperative analgesia and sedation after preoperative saphenous and sciatic nerve blockade, preoperative lumbosacral epidural injection and perioperative intravenous (IV) morphine, lidocaine and ketamine infusions in dogs undergoing stifle arthroscopy and tibial plateau leveling osteotomy (TPLO) under general anesthesia.Study designProspective, blinded, randomized, clinical comparison study.AnimalsA total of 45 dogs weighing 33.9 (15.9–56.7) kg and aged 5.2 (1.0–12.0) years, mean (range), undergoing elective unilateral TPLO for spontaneous cranial cruciate ligament rupture.MethodsClient-owned dogs were enrolled. Dogs were randomly assigned to one of three groups: group MLK, perioperative IV morphine, lidocaine and ketamine infusion; group EPID, lumbosacral epidural with ropivacaine and morphine; or group SSNB, saphenous and sciatic nerve blockade with ropivacaine. Routine stifle arthroscopy followed by TPLO surgery was performed. Sedation and pain scores were assessed at 0, 2, 4, 8 and 24 hours following extubation. Rescue analgesia was administered as prescribed by Glasgow composite pain score–short form score >5.ResultsSedation scores for MLK were higher than EPID and SSNB. Pain scores for SSNB were lower than those for EPID and MLK. No significant differences were found in anesthesia duration or surgery duration among groups. No dogs required rescue analgesia.Conclusions and clinical relevanceAlthough analgesia was adequate in all groups, the best combination of analgesia without increased sedation was recorded for SSNB.  相似文献   
54.
OBJECTIVE: To determine the effect of meloxicam and flunixin meglumine on recovery of ischemia-injured equine jejunum. ANIMALS: 18 horses. PROCEDURES: Horses received butorphanol tartrate; were treated IV with saline (0.9% NaCl) solution (SS; 12 mL; n = 6), flunixin meglumine (1.1 mg/kg; 6), or meloxicam (0.6 mg/kg; 6) 1 hour before ischemia was induced for 2 hours in a portion of jejunum; and were allowed to recover for 18 hours. Flunixin and SS treatments were repeated after 12 hours; all 3 treatments were administered immediately prior to euthanasia. Selected clinical variables, postoperative pain scores, and meloxicam pharmacokinetic data were evaluated. After euthanasia, assessment of epithelial barrier function, histologic evaluation, and western blot analysis of ischemia-injured and control jejunal mucosa samples from the 3 groups were performed. RESULTS: Meloxicam- or flunixin-treated horses had improved postoperative pain scores and clinical variables, compared with SS-treated horses. Recovery of transepithelial barrier function in ischemia-injured jejunum was inhibited by flunixin but permitted similarly by meloxicam and SS treatments. Eighteen hours after cessation of ischemia, numbers of neutrophils in ischemia-injured tissue were higher in horses treated with meloxicam or flunixin than SS. Plasma meloxicam concentrations were similar to those reported previously, but clearance was slower. Changes in expression of proteins associated with inflammatory responses to ischemic injury and with different drug treatments occurred, suggesting cyclooxygenase-independent effects. CONCLUSIONS AND CLINICAL RELEVANCE: Although further assessment is needed, these data have suggested that IV administration of meloxicam may be a useful alternative to flunixin meglumine for postoperative treatment of horses with colic.  相似文献   
55.
OBJECTIVE: To determine historical, physical, and microbiologic findings in horses with limb cellulitis and identify factors associated with short- and long-term outcome. DESIGN: Retrospective case series. ANIMALS: 44 horses with limb cellulitis. PROCEDURES: Information obtained from medical records included use, history, affected limb, diagnostic procedures, treatment, and short-term outcome. Long-term follow-up information was obtained by means of a telephone survey. RESULTS: Twenty-four horses had primary cellulitis, and 18 of the 24 (75%) had a hind limb affected. Results of microbiologic culture were positive for all 20 horses with primary cellulitis from which specimens were obtained, with coagulase-positive Staphylococcus spp recovered from 12 of the 20. Short-term survival rate was 67% (16/24) for horses with primary cellulitis; 7 of the 9 horses available for long-term follow-up were being used for their intended use, and 4 had had a recurrence. Results of microbiologic culture were positive for 13 of the 16 (81%) horses with secondary cellulitis from which specimens were obtained. Short-term survival rate for horses with secondary cellulitis was 90% (18/20). Eleven of the 17 horses available for long-term follow-up were being used for their intended use; 2 had had a recurrence. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that cellulitis can be a life-threatening condition in horses. Horses that were febrile at admission or that developed laminitis were significantly less likely to survive. The prognosis for return to function was guarded, and recurrence was a potential concern.  相似文献   
56.
Cyclooxygenase (COX) inhibitors and the intestine   总被引:1,自引:0,他引:1  
Nonsteroidal anti-inflammatory drugs (NSAIDs) have long been used for the treatment of pain and inflammation because of their inhibitory effects on cyclooxygenase (COX). For almost as long as NSAIDs have been in use, multiple adverse effects have been noted. Assessment of many of these adverse effects have been complicated because of the discovery of multiple splice variants of the cox gene, and a greater array of COX inhibitors, especially the COX-2 selective inhibitors have become available. Some of these adverse effects cannot be readily explained by the effect of these drugs on COX. This has sparked a new field of investigation into the COX-independent effects of the COX inhibitors. The major noncyclooxygenase targets of the COX inhibitors of particular relevance to inflammation and the gastrointestinal tract are phosphatidylinositol 3'-kinase Akt signaling, uncoupling of oxidative phosphorylation, PPARgamma, nuclear factor KB, mitogen activated protein kinases, and heat shock proteins.  相似文献   
57.
A single‐factor experiment was conducted to investigate the effects of dietary astaxanthin concentration on the skin colour of snapper. Snapper (mean weight=129 g) were held in white cages and fed one of seven dietary levels of unesterified astaxanthin (0, 13, 26, 39, 52, 65 or 78 mg astaxanthin kg?1) for 63 days. Treatments comprised four replicate cages, each containing five fish. The skin colour of all fish was quantified using the CIE L*, a*, b* colour scale after 21, 42 and 63 days. In addition, total carotenoid concentrations of the skin of two fish cage?1 were determined after 63 days. Supplementing diets with astaxanthin strongly affected redness (a*) and yellowness (b*) values of the skin at all sampling times. After 21 days, the a* values increased linearly as the dietary astaxanthin concentration was increased before a plateau was attained between 39 and 78 mg kg?1. The b* values similarly increased above basal levels in all astaxanthin diets. By 42 days, a* and b* values increased in magnitude while a plateau remained between 39 and 78 mg kg?1. After 63 days, there were no further increases in measured colour values, suggesting that maximum pigmentation was imparted in the skin of snapper fed diets >39 mg kg?1 after 42 days. Similarly, there were no differences in total carotenoid concentrations of the skin of snapper fed diets >39 mg kg?1 after 63 days. The plateaus that occurred in a* and b* values, while still increasing in magnitude between 21 and 42 days, indicate that the rate of astaxanthin deposition in snapper is limited and astaxanthin in diets containing >39 mg astaxanthin kg?1 is not efficiently utilized. Astaxanthin retention after 63 days was greatest from the 13 mg kg?1 diet; however, skin pigmentation was not adequate. An astaxanthin concentration of 39 mg kg?1 provided the second greatest retention in the skin while obtaining maximum pigmentation. To efficiently maximize skin pigmentation, snapper growers should commence feeding diets containing a minimum of 39 mg unesterified astaxanthin kg?1 at least 42 days before sale.  相似文献   
58.
The biosynthesis of volatile esters by Red Delicious apples was investigated by incubating fruit tissue with deuterated flavor precursors at various times after controlled atmosphere (CA) storage and measuring deuterium incorporation into branched-chain ester volatiles. 2-Methylbutyl acetate was the only volatile not significantly reduced by CA storage. Conversion of 2-methylbutanol to 2-methylbutyl acetate and of 2-methylbutanoic acid to ethyl 2-methylbutanoate and to hexyl 2-methylbutanoate was limited by the availability of 2-methylbutyl substrates but not by acetyl-CoA, ethanol, or hexanol, respectively. The enzymatic activity required for these reactions declined during CA storage. The conversion of 2-methylbutanoic acid to 2-methylbutanol was also substrate limited, but enzymic activity appeared stable in storage. Biosynthesis of both 2-methylbutanoic acid and 2-methylbutanol, from isoleucine, was severely depressed under CA storage. The reduced metabolism of isoleucine to 2-methylbutanoyl-CoA may be the primary reason for reduced branched-chain ester synthesis in CA-stored Red Delicious apples. Enantioselective gas chromatography-mass spectrometry confirmed that the chirality of (S)-2-methylbutyl acetate derives from l-isoleucine with the other enzymes in this pathway not being enantiospecific. Treatment of tissue samples with 2-methylbut-2E-enal gave only (S)-2-methylbutyl acetate, indicating that biosynthesis was not via tiglyl-CoA.  相似文献   
59.
Natal homing in a marine fish metapopulation   总被引:1,自引:0,他引:1  
Identifying natal origins of marine fishes is challenging because of difficulties in conducting mark-recapture studies in marine systems. We used natural geochemical signatures in otoliths (ear bones) to determine natal sources in weakfish (Cynoscion regalis), an estuarine-spawning marine fish, in eastern North America. Spawning site fidelity ranged from 60 to 81%, comparable to estimates of natal homing in birds and anadromous fishes. These data were in contrast to genetic analyses of population structure in weakfish. Our findings highlight the need for consideration of spatial processes in fisheries models and have implications for the design of marine reserves in coastal regions.  相似文献   
60.
Journal of Plant Diseases and Protection - Prior to the first occurrence of chestnut blight in 1976, leaf spot caused by Cylindrosporium castaneae was one of the most important diseases of European...  相似文献   
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