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21.
CASE HISTORY A 3-year-old male Labrador retriever was presented with a history of dietary indiscretion followed by vomiting and abdominal pain.

CLINICAL FINDINGS AND TREATMENT: Abdominal ultrasonography revealed the presence of a fluid-filled cystic structure in the region of the pancreas. Flocculent, dark fluid was drained from the cystic structure during exploratory celiotomy prior to resection of the lateral cystic wall. Omentum was sutured into the cystic cavity to provide drainage and enhance immune response. A jejunostomy feeding tube was placed. Post-surgical care consisted of antibiotic therapy. The dog was clinically normal at 1 and 7 months post-operatively and the pancreas appeared normal on final ultrasonographic examination.

CLINICAL RELEVANCE: This case describes the use of omentum to provide physiological drainage of a pancreatic pseudocyst. This surgical technique may help clinicians manage patients with this condition in the future.  相似文献   
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The vascular endothelial growth factor (VEGF) is essential for follicular development by promoting follicular angiogenesis, as well as for the proliferation and survival of granulosa cells. The biological effects of VEGF are regulated by two membrane receptors, VEGFR1 and VEGFR2, and two soluble receptors, sVEGFR1 and sVEGFR2, which play an antagonistic role. Thus, the objective of this study was to identify the mRNA expression pattern of total VEGF, VEGFR1, VEGFR2, sVEGFR1 and sVEGFR2 in bovine preselected follicles (PRF) and post‐selected follicles (POF). The mRNA expression of these five genes in both granulosa cells (GC) and theca cells (TC) was compared between follicles classified as PRF and POF based on their diameter and on their ratio of estradiol/progesterone (E2/P4). Results showed a lower expression of mRNA of sVEGFR1 and sVEGFR2 in POF than in PRF (p < .05). Regarding the mRNA expression of total VEGF, VEGFR1 and VEGFR2, there was no difference between POF and PRF follicles (p > .05). Our results showed that the mRNA expression of VEGFR2 and sVEGFR1 was more abundant than the expression of VEGFR1 and sVEGFR2, while GC was the main source of mRNA for total VEGF. On the other hand, TC was the follicular compartment where the receptors were most expressed. Our results suggest that non‐dominant follicles maintain a greater concentration of the mRNA expression of both membrane and soluble VEGF receptors. On the other hand, follicular dominance is related to a reduction in the mRNA expression of sVEGFR1 and sVEGFR2, which may favour VEGF binding with VEGFR2 and, hence, improve the follicular health and development.  相似文献   
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Chemical vapor deposition of germanium onto the silicon (001) surface at atmospheric pressure and 600 degrees Celsius has previously been shown to produce distinct families of smaller (up to 6 nanometers high) and larger (all approximately 15 nanometers high) nanocrystals. Under ultrahigh-vacuum conditions, physical vapor deposition at approximately the same substrate temperature and growth rate produced a similar bimodal size distribution. In situ scanning tunneling microscopy revealed that the smaller square-based pyramids transform abruptly during growth to significantly larger multifaceted domes, and that few structures with intermediate size and shape remain. Both nanocrystal shapes have size-dependent energy minima that result from the interplay between strain relaxation at the facets and stress concentration at the edges. A thermodynamic model similar to a phase transition accounts for this abrupt morphology change.  相似文献   
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The synthesis of massive arrays of monodispersed carbon nanotubes that are self-oriented on patterned porous silicon and plain silicon substrates is reported. The approach involves chemical vapor deposition, catalytic particle size control by substrate design, nanotube positioning by patterning, and nanotube self-assembly for orientation. The mechanisms of nanotube growth and self-orientation are elucidated. The well-ordered nanotubes can be used as electron field emission arrays. Scaling up of the synthesis process should be entirely compatible with the existing semiconductor processes, and should allow the development of nanotube devices integrated into silicon technology.  相似文献   
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OBJECTIVES: To determine the effects of orally administered omeprazole, as enteric-coated capsules, on baseline and stimulated gastric acid secretion in horses. ANIMALS: 5 healthy 8-year-old mixed-breed horses fitted with gastric cannulas. PROCEDURE: Enteric-coated granules of omeprazole were mixed with corn syrup and administered orally once daily for 5 consecutive days. On days 1 and 5 beginning 5 hours after omeprazole administration, 4 gastric fluid samples were collected, each for 15 minutes, via the gastric cannula (baseline samples). Pentagastrin was administered IV as a constant infusion for the subsequent 2 hours, and 15-minute gastric fluid samples were again collected (stimulated samples). Fluid volume, acidity (mmol H-/L), and pH and gastric acid production (mmol H+) were determined for all baseline samples and for stimulated samples collected during the second hour of pentagastrin infusion. Control experiments were done in a similar manner after giving corn syrup alone to the same horses. RESULTS: Compared with values obtained during control experiments, baseline and stimulated gastric fluid acidity and gastric acid production significantly decreased, and the mean pH of gastric fluid samples significantly increased, after horses were given 5 daily doses of omeprazole. CONCLUSIONS AND CLINICAL RELEVANCE: Enteric-coated omeprazole (1.0 mg/kg of body weight; PO) administered once daily for 5 days significantly inhibited unstimulated and pentagastrin-stimulated gastric acid secretion in horses. This commercially available formulation of omeprazole may be efficacious in the treatment of gastroduodenal ulcers in horses.  相似文献   
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The effects of feeding chemically treated dietary supplements (CTDS) containing sunflower oil and dl-alpha-tocopheryl acetate (TA) on alpha-tocopherol content and fatty acid profile in edible tissues of lambs were estimated. Compared with lambs fed control diet (CD), lambs fed CD plus 250 IU of either TA or CTDS increased serum alpha-tocopherol. The CTDS-fed lambs further increased serum alpha-tocopherol by 29% over those fed CD plus 250 IU of TA. Lambs supplemented with TA or CTDS increased alpha-tocopherol in muscle and adipose tissues as compared with lambs fed CD. The CTDS-fed lambs had higher levels of alpha-tocopherol in gluteus medius (7.55 vs 6.05 mug/g), psoas major (7.43 vs 6.02 mug/g), and subcutaneous fat (12.6 vs 9.98 mug/g) compared with the TA-fed lambs. Feeding lambs CTDS also substantially increased levels of linoleic acid in the adipose tissues while decreasing the content of palmitic and oleic acids.  相似文献   
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Seminal plasma (SP) contains several types of compounds derived from the epididymides and accessory glands. The aim of this study was to examine the protein composition of different ejaculate fractions. Trial I: fractionated ejaculates were collected from two normal and two subfertile stallions. Samples containing pre‐sperm fluid and the first sperm‐rich jets (HIGH‐1), the main sperm‐rich portion (HIGH‐2), the jets with low sperm concentrations (LOW), and a combined whole‐ejaculate (WE) sample was centrifuged, and the SP was filtered and frozen. A part of each SP sample was stored (5°C, 24 h) with spermatozoa from HIGH‐2 and skim milk extender. Sperm motility was evaluated after storage in extender mixed with the stallion’s own SP or SP from one of the other stallions (sperm from a normal stallion stored in SP from a subfertile stallion and vice versa). Protein composition was analysed using reverse‐phase liquid chromatography (RP‐HPLC), N‐terminal sequencing and mass spectrometry. The area‐under‐the‐curve (AUC) was used for quantitative comparison of proteins within fractions. Trial II: semen samples were collected from seven stallions. Fractions with the highest (HIGH) and lowest (LOW) sperm concentrations and WE samples were examined using SDS‐PAGE and densitometry. No significant differences emerged between fractions in the AUC‐values of the Horse Seminal Protein‐1 (HSP‐1) and HSP‐2 peaks, or the peak containing HSP‐3 and HSP‐4 (HSP‐3/4). Levels of HSP‐1, HSP‐2 and HSP‐3/4 were not significantly correlated with total sperm motility, progressive sperm motility or average path velocity after storage. Significant differences between ejaculate fractions in the amount of different protein groups present in SP were not found in Trial I; but in Trial II, the proteins in the 60–70 kDa range were more abundant in LOW than in HIGH and WE, indicating that this band contained proteins derived mainly from the seminal vesicles, which produce most of the SP in LOW.  相似文献   
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This review of tick paralysis caused by Ixodes holocyclus in Australia addresses the question: What are the key discoveries that have enabled effective treatment and prevention of tick paralysis in dogs and cats? Critical examination of 100 years of literature reveals that arguably only three achievements have advanced treatment and prevention of tick paralysis in animals. First, the most significant treatment advance was the commercial availability of tick antiserum in the 1930s. Hyperimmune serum currently remains the only specific anti-paralysis tick therapy available to veterinarians in Australia. Second, advances in veterinary critical care have increased survival rates of the most severely affected dogs and cats. Critical care advancements have been enabled through specialised veterinary hospitals that can provide appropriate care 24 h a day, and advanced training of veterinarians, veterinary nurses and technicians. Third, perhaps that biggest advance of all in the last 100 years of research has been the commercial availability of the isooxazoline class of acaricidal preventatives in Australia specifically for I. holocyclus. This highly effective class of preventatives offers long duration of action, low cost, spot-on or oral formulations and a low rate of adverse reactions. Animal owners and veterinarians now have the most useful tool of all – a reliable preventative. This review reveals the key events in research over the last 100 years and the tortuous pathway to delivering better treatment and preventative options for this enigmatic Australian parasite.  相似文献   
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