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31.
Ultrasonography and radiography are standard diagnostic tests for cats with suspected splenic disease, however published information on outside sources of variation are currently lacking. The purpose of this prospective, randomized, crossover group study was to evaluate effects of common sedative drugs on the sonographic and radiographic characteristics of the spleen in healthy cats. Fifteen healthy adult research cats were randomly assigned into one of three groups corresponding to different sequences of administration of five sedative drugs/drug combinations (acepromazine; butorphanol; dexmedetomidine; midazolam and butorphanol (MB); and dexmedetomidine, butorphanol, and ketamine (DBK)), administered at 1‐week intervals. At each visit, three‐view abdominal radiographic and ultrasonographic examinations were performed prior to sedation and repeated 15‐30 min and 2‐3 h post sedation. Two board‐certified radiologists (one ACVR and one ACVR/ECVDI) evaluated the anonymized and randomized images. Acepromazine resulted in significantly increased sonographic and radiographic splenic measurements from baseline, which remained significantly increased 2‐3 h post sedation. The mean magnitude of this change ranged from 0.9 mm (tail height, SD 1.4 mm) to 1.8 mm (body height, SD 1.7 mm) for ultrasound, and was 2.2 mm (ventrodorsal width, SD 2.3 mm) for radiographs. With butorphanol, there was no significant change in splenic size. For dexmedetomidine, MB, and DBK, there was a trend toward increased splenic size from baseline to the first post‐sedation timepoint, which was statistically significant for radiographic measurements, although not for ultrasound. Findings indicated that acepromazine should be avoided prior to imaging while butorphanol may be used when sedation is needed in cats presenting for potential splenic disease.  相似文献   
32.
Monozygotic twinning has not previously been genetically confirmed in the dog. This case report describes the finding of two viable male monozygotic foetuses within one placental site during caesarean section. Their umbilical cords attached to a single placenta. Genetic profiling using a total of 38 microsatellite markers, as well as amelogenin and SRY for sex determination, revealed identical DNA profiles, whether derived from blood or tissue (buccal swabs) samples. To the best of our knowledge, this is the first report of monozygotic twinning in the dog confirmed using DNA profiling.  相似文献   
33.
34.

Objective

To evaluate cardiopulmonary and recovery characteristics of horses administered total intravenous anesthesia (TIVA) with xylazine and ketamine combined with midazolam or propofol.

Study design

Randomized crossover study.

Animals

A group of eight adult horses, aged 7–22 years, weighing 493–740 kg.

Methods

Horses were administered xylazine (1 mg kg?1) intravenously (IV), and anesthesia was induced with ketamine (2.2 mg kg?1) IV. Anesthesia was maintained for 45 minutes via IV infusion of xylazine (0.016 mg kg?1 minute?1) and ketamine (0.03 mg kg?1 minute?1) combined with midazolam at 0.002 mg kg?1 minute?1 (MKX), propofol at 0.05 mg kg?1 minute?1 (PKXlow) or propofol at 0.1 mg kg?1 minute?1 (PKXhigh). Additional ketamine was administered if a horse moved spontaneously. Cardiopulmonary variables, blood gases, lactate concentration, packed cell volume and total solids were recorded before sedation (baseline), at 10, 20, 30 and 45 minutes during TIVA and 10 minutes after standing. Recovery variables and quantitative recovery scores were compared. Significance was set at p < 0.05.

Results

Additional ketamine was required for 50% of MKX horses. Systolic arterial pressure was elevated in MKX at 20 minutes compared with baseline (p = 0.043), at 10 and 20 minutes compared with PKXhigh (p = 0.007, p = 0.024) and at 20 and 30 minutes compared with PKXlow (p = 0.009, p = 0.02). MKX horses (5/8) were hypertensive compared with PKXlow (1/8; p = 0.017). All horses became hypoxemic (PaO2 ≤80 mmHg; 10.7 kPa) during TIVA. Recovery variables did not differ among treatments.

Conclusions and clinical relevance

PKXlow and PKXhigh had similar cardiopulmonary and recovery performance compared with MKX. PKX combinations provided superior quality of anesthesia to that of MKX. A combination of propofol, ketamine and xylazine administered as TIVA can be used in horses to provide anesthesia for short procedures. Supplemental oxygen is recommended.  相似文献   
35.
36.
Traditional management of sand sagebrush (Artemisia filifolia) rangelands has emphasized sagebrush control to increase forage for livestock. Since the 1950s shrub removal has been primarily achieved with herbicides. Concerns over declining lesser prairie-chicken (Tympanuchus pallidicinctus; LPC) populations have led to increased scrutiny over the use of herbicides to control shrubs. The objective of our research was to describe changes to LPC habitat qualities following chemical control of sand sagebrush in northwest Oklahoma. Study pastures ranged in size from 10 to 21 ha. Five pastures were sprayed with 2,4-dichlorophenoxyacetic acid (2,4-D) in 2003 (RECENT), five were sprayed with 2,4-D in 1984 (OLD), and four received no treatment (SAGE). We measured habitat structure (sagebrush cover, sagebrush density, visual obstruction &lsqb;VO], and basal grass cover), and dietary resources (forb density, forb richness, and grasshopper density) in all pastures from 2003 to 2006. OLD and RECENT pastures had less sagebrush (cover and density) and VO than SAGE pastures. OLD pastures produced more annual forbs than either SAGE or RECENT pastures. SAGE pastures had more perennial forbs than RECENT pastures. Herbicide application reduced protective cover while providing no increase in forb abundance in RECENT pastures. Our results indicated that it may take several years to realize increases in annual forbs following application of 2,4-D. However, loss of protective cover may persist for multiple years (20+ yr), and removal of sagebrush did not increase forb richness or grasshopper abundance. Thus, 2,4-D may have limited use as a habitat management tool because it takes numerous years to reap the benefit of increased forb abundance while reducing habitat structure in the long term.  相似文献   
37.
Tight junctions (TJs) in inter-Sertoli junctional areas and epididymal epithelia build up the blood–testis barrier (BTB) and the blood–epididymal barrier (BEB), respectively. In this study, the expression of occludin, an integral member of the TJs, was examined in testis and different regions of epididymis of Lepus sinensis coreanus , an Korean wild rabbit species. In testis, intense occludin immunoreactivity was found in the basally located inter-Sertoli junctional area together with diffused immunoreactivity of occludin in the cytoplasm of Sertoli cells. It can be suggested that occludin is one of the robust elements of BTB in seminiferous tubules of rabbit testis. In proximal and distal caput epididymis, occludin immunoreactivity was found in the lateral as well as apical contacts of epithelial cells. In corpus epididymis, intense occludin immunoreactivity was found in the basolateral as well as apical contacts of epithelial cells together with cytoplasmic signal. In cauda epididymis, occludin immunoreactivity in luminal epithelia was relatively strong but largely found in the cytoplasm. This suggests that intriguing regulatory mechanisms differentially recruit occludin to the TJ in the different regions of epididymal epithelia. The differences in the subcellular localization as well as expression levels of occludin among the epididymal segments may reflect differential paracellular permeability of epithelia along the epididymal tubules and be correlated with sperm maturation in rabbit. In Western blot, a major form of occludin was MW 62 kDa together with small fragments of MW 34–39 kDa in testis and epididymis, suggesting the peptide cleavage of occludin. This is the first report on the molecular nature of TJs in a wild rabbit testis and epididymis.  相似文献   
38.
Non-symptomatic sugarcane plants infected with Sugarcane Yellow Leaf Virus showed starch in mesophyll and bundle sheath cells. In situ-hybridization of mRNAs of sucrose-phosphate phosphatase and ADP-glucose pyrophosphorylase revealed that infected leaves contained SPPase and AGPase in mesophyll cells, Kranz cells and bundle sheath cells. In contrast virus-free leaves contained SPPase only in Kranz cells and AGPase only in bundle sheath cells. Infected leaves exhibited ultrastructural changes in Kranz cell chloroplasts and a shift of the chlorophyll a/b ratio. No obstruction of plasmodesmata was observed. The results indicate that SCYLV-infected plants, even when visually non-symptomatic, underwent strong metabolic and ultrastructural changes.  相似文献   
39.
ABSTRACT Expression of the Arabidopsis thaliana gene PROLIFERA (PRL) was examined during development of root-knot and cyst nematode feeding sites. These obligate plant parasites establish specialized feeding structures in roots that allow them to withdraw nutrients from the host. In the process of establishing feeding sites, nematodes alter cell cycle regulation. PRL is normally expressed specifically in dividing cells at all stages of plant development and was used here as a marker for cell division. PRL expression, reported from a PRL::GUS fusion protein, was detected in nematode feeding sites of both root-knot and cyst nematodes from the earliest stages of infection in both giant cells and syncytia. However, unlike other cell cycle genes, expression of PRL was detected only occasionally in cells surrounding the feeding sites. PRL::GUS activity persisted until late in the infection cycle, past the time when other cell cycle genes are expressed. These data indicate that some aspects of the PRL expression pattern during nematode infection differ from that of other cell cycle genes.  相似文献   
40.
SUMMARY: Biochemical profiles, restriction endonuclease analysis (REA) and ribotyping were used to investigate Pasteurella multocida isolates from outbreaks of fowl cholera on 7 turkey farms in New South Wales. While only a single isolate was available from 5 of the farms, multiple isolates, 4 and 12 respectively, were available from the other 2 farms. The available field evidence suggested that 8 outbreaks had occurred with one farm suffering 2 outbreaks. The isolates obtained were all confirmed as Pasteurella multocida . Biochemical profiles allocated the isolates to 4 groups, 3 being variants of P multocida subsp multocida and the fourth being P multocida subsp septica . REA performed with Hpall established 7 groups. Ribotyping using the Hpall digests probed with the 16S rRNA operon of Haemophilus paragallinarum recognised the same 7 groups as REA. Unlike the biochemical profiles, both REA and ribotyping provided a fine subdivision that identified outbreaks as either related or unrelated. The REA and ribotyping patterns as well as biochemical profiles were stable for all isolates from the outbreaks in which multiple isolates were obtained from either the same bird or from different birds. REA and ribotyping were found to be superior to biotyping methods for the investigation of fowl cholera outbreaks.  相似文献   
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