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31.
CLINICAL SUMMARY: A 7-month-old female Persian cat presented with gastrointestinal (GI) necrosis and perforation caused by Rhizomucor species. Unfortunately, the cat died of bacterial peritonitis and sepsis before a definitive diagnosis, based on histopathology and fungal culture, was achieved. PRACTICAL RELEVANCE: This appears to be the first reported case of GI disease caused by Rhizomucor species in a cat. Mucorales infections typically cause acute and rapidly progressive disease. As illustrated by this case, clinicians should be alert to the potentially fatal consequences of an opportunistic Rhizomucor species infection in their feline patients.  相似文献   
32.
ObjectiveTo test if the addition of butorphanol by constant rate infusion (CRI) to medetomidine–isoflurane anaesthesia reduced isoflurane requirements, and influenced cardiopulmonary function and/or recovery characteristics.Study designProspective blinded randomised clinical trial.Animals61 horses undergoing elective surgery.MethodsHorses were sedated with intravenous (IV) medetomidine (7 μg kg?1); anaesthesia was induced with IV ketamine (2.2 mg kg?1) and diazepam (0.02 mg kg?1) and maintained with isoflurane and a CRI of medetomidine (3.5 μg kg?1 hour?1). Group MB (n = 31) received butorphanol CRI (25 μg kg?1 IV bolus then 25 μg kg?1 hour?1); Group M (n = 30) an equal volume of saline. Artificial ventilation maintained end-tidal CO2 in the normal range. Horses received lactated Ringer’s solution 5 mL kg?1 hour?1, dobutamine <1.25 μg kg?1 minute?1 and colloids if required. Inspired and exhaled gases, heart rate and mean arterial blood pressure (MAP) were monitored continuously; pH and arterial blood gases were measured every 30 minutes. Recovery was timed and scored. Data were analyzed using two way repeated measures anova, independent t-tests or Mann–Whitney Rank Sum test (p < 0.05).ResultsThere was no difference between groups with respect to anaesthesia duration, end-tidal isoflurane (MB: mean 1.06 ± SD 0.11, M: 1.05 ± 0.1%), MAP (MB: 88 ± 9, M: 87 ± 7 mmHg), heart rate (MB: 33 ± 6, M: 35 ± 8 beats minute?1), pH, PaO2 (MB: 19.2 ± 6.6, M: 18.2 ± 6.6 kPa) or PaCO2. Recovery times and quality did not differ between groups, but the time to extubation was significantly longer in group MB (26.9 ± 10.9 minutes) than in group M (20.4 ± 9.4 minutes).Conclusion and clinical relevanceButorphanol CRI at the dose used does not decrease isoflurane requirements in horses anaesthetised with medetomidine–isoflurane and has no influence on cardiopulmonary function or recovery.  相似文献   
33.
The tetracycline resistance gene, tet(B), has been described previously in Gram negative bacteria. In this study tet(B) was detected in plasmid extracts from 17/111 (15%) Streptococcus suis isolates from diseased pigs, representing the first report of this resistance gene in Gram positive bacteria.  相似文献   
34.

Background

The tomato (Solanum lycopersicum L.) plant is both an economically important food crop and an ideal dicot model to investigate various physiological phenomena not possible in Arabidopsis thaliana. Due to the great diversity of tomato cultivars used by the research community, it is often difficult to reliably compare phenotypes. The lack of tomato developmental mutants in a single genetic background prevents the stacking of mutations to facilitate analysis of double and multiple mutants, often required for elucidating developmental pathways.

Results

We took advantage of the small size and rapid life cycle of the tomato cultivar Micro-Tom (MT) to create near-isogenic lines (NILs) by introgressing a suite of hormonal and photomorphogenetic mutations (altered sensitivity or endogenous levels of auxin, ethylene, abscisic acid, gibberellin, brassinosteroid, and light response) into this genetic background. To demonstrate the usefulness of this collection, we compared developmental traits between the produced NILs. All expected mutant phenotypes were expressed in the NILs. We also created NILs harboring the wild type alleles for dwarf, self-pruning and uniform fruit, which are mutations characteristic of MT. This amplified both the applications of the mutant collection presented here and of MT as a genetic model system.

Conclusions

The community resource presented here is a useful toolkit for plant research, particularly for future studies in plant development, which will require the simultaneous observation of the effect of various hormones, signaling pathways and crosstalk.  相似文献   
35.
The levels of hydrophilic, lipophilic, and enzymatic antioxidants, the oxidative damage to lipids and proteins, and the fatty acid patterns of triglyceride and phospholipid fractions were assayed in fresh muscle tissue of rainbow trouts (Oncorhynchus mykiss) and sea basses (Dicentrarchus labrax) during aging, to investigate the correlation between oxidative stress and aging processes in fish. The present studies suggests that lipid peroxidation and accumulation of oxidized proteins during in vivo aging are most likely to be linked with an age-dependent decline of lipophilic antioxidants (CoQH(2), CoQ, and vitamin E) and vitamin C contents in muscle tissue, whereas fish aging is not linked to a decline in antioxidant enzymes and reduced glutathione levels. Lipophilic antioxidant and vitamin C levels represent a reliable marker of oxidative stress during aging, and their determination might be useful for the assessment of fish age.  相似文献   
36.
In 1998 the protected population of Perameles gunnii (eastern barred bandicoot) at Woodlands Historic Park, Victoria, Australia became functionally extinct following removals of individuals for translocation between 1994 and 1996. Population viability analysis and data collected whilst the population was in decline are used to explore the impact that these removals had on the decline of the P. gunnii population at Woodlands. Due to some ambiguities in the life history of P. gunnii at Woodlands, two structurally different population models were used. Explicitly including the removal of animals in the analysis indicates that there may be at least a three-fold increase in the risk of quasiextinction due to removals. In some scenarios, over 17% of the trajectories decrease to a level less than or equal to 10 females within the observed time period of the collapse of the population, that is by April 1998. The modelling approach identified a number of critical factors in the decline of the population, such as variation in survival rates. By representing the life history strategy using two alternate models, quantitative statements about the impact that removals had on the population decline at Woodlands are made. While removals probably contributed to the collapse of the population, removals were not the sole cause of population decline. The real reasons for decline remain unknown; however, it is likely to be closely linked to habitat decline, difficult environmental conditions and predation. If P. gunnii are reintroduced to Woodlands again, then the models presented here may help to develop management strategies to establish a self sustaining population, as well as exploring translocations options.  相似文献   
37.
Isoflavonoids isolated from Cuban propolis   总被引:3,自引:0,他引:3  
Chemical investigation of a red-type Cuban propolis sample has led to the isolation of 11 isoflavonoids (2 isoflavones, 3 isoflavans, and 6 pterocarpans), together with gallic acid, isoliquiritigenin, and (-)-liquiritigenin. Structural determination, including the absolute stereochemistry, was accomplished by spectroscopic analysis, particularly CD and 2D NMR techniques. The fragmentation behavior of pterocarpans was studied by electrospray ionization (ESI) tandem mass spectrometry (MS/MS) using an ion-trap analyzer, and a generalized fragmentation pathway, useful in the identification and structural characterization of pterocarpans, is proposed. Isoflavonoids are reported for the first time from propolis samples.  相似文献   
38.
Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the "Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)", Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar.  相似文献   
39.
40.
The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis.  相似文献   
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