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1.
Gastric emptying is the process by which food is delivered to the small intestine at a rate and in a form that optimizes intestinal absorption of nutrients. The rate of gastric emptying is subject to alteration by physiological, pharmacological, and pathological conditions. Gastric emptying of solids is of greater clinical significance because disordered gastric emptying rarely is detectable in the liquid phase. Imaging techniques have the disadvantage of requiring restraint of the animal and access to expensive equipment. Radiographic methods require administration of test meals that are not similar to food. Scintigraphy is the gold standard method for assessment of gastric emptying but requires administration of a radioisotope. Magnetic resonance imaging has not yet been applied for assessment of gastric emptying in small animals. Ultrasonography is a potentially useful, but subjective, method for assessment of gastric emptying in dogs. Gastric tracer methods require insertion of gastric or intestinal cannulae and are rarely applied outside of the research laboratory. The paracetamol absorption test has been applied for assessment of liquid phase gastric emptying in the dog, but requires IV cannulation. The gastric emptying breath test is a noninvasive method for assessment of gastric emptying that has been applied in dogs and cats. This method can be carried out away from the veterinary hospital, but the effects of physiological and pathological abnormalities on the test are not known. Advances in technology will facilitate the development of reliable methods for assessment of gastric emptying in small animals.  相似文献   
2.
The objective of this study was to assess post-gastric processing of octanoic acid (OA) by comparing the rate of recovery of 13C in breath with the rate of recovery of 2H in saliva following ingestion of [2H/13C]OA. A test meal with 100mg [13C]OA and 750 mg [2H]OA was ingested on two separate occasions by one dog. Exhaled breath and saliva samples were collected at set time points for 6h following ingestion of the test meal. Two indices were computed, half recovery time (t(1/2)) and the time of peak excretion (t(max)). Recovery of 2H in saliva was quicker than recovery of 13C in breath as determined by the difference in the indices for each isotope; 1.33 and 1.59 h for t(1/2) and t(max), respectively. These findings suggest that the post-gastric processing of OA imposes a delay on the recovery of 13C in breath in the dog, as occurs in man and in the horse.  相似文献   
3.
Diffusion processes involving polymers are common in scientific and engineering separations and are a major component of biological functions. Analyses of these systems are usually based on versions of the Stokes-Einstein equation, although order of magnitude deviations have been observed. Presented here is a theoretical correction to the Stokes-Einstein equation containing a "local viscosity" function that combines diffusional hydrodynamics with Maxwell's treatment of electrical resistance in inhomogeneous regions. The resulting equation accurately predicts experimental diffusion data within tight bounds for polymer concentrations from 0 to 9 percent. It requires knowledge only of thermodynamics and of pure solvent and solution viscosities.  相似文献   
4.
G.C. Fisher  Oi-Lai Yam 《Geoderma》1984,32(4):339-345
Aqueous extracts of leaves and shoots of Calluna vulgaris, Erica tetralix, and Betula pendula were reacted with iron compounds in the laboratory. Extracts of B. pendula were found to be most active in solubilizing iron. The iron mobilizing capacity of extracts of C. vulgaris depended upon plant age, season, and soil conditions. C. vulgaris shoots were found to be more readily leached of their soluble organic matter than those of B. pendula but yielded little soluble inorganic material. C. vulgaris extracts were the most acid (pH 4.2–4.5) of those examined.  相似文献   
5.
The aim of this study was to evaluate the dietary dosages of turmeric that enhance immune response and disease resistance against the opportunistic pathogens Aeromonas hydrophila in Labeo rohita fingerlings. Hence, four different dosages of turmeric at 0.1, 0.5, 1.0 and 5.0 g kg?1 feed were given to the fingerlings of L. rohita for 60 days at 4% body weight. At every 20‐day interval, different biochemical, haematological, enzymatic and immunological parameters of fish were evaluated. After 60 days, fish were challenged with A. hydrophila. The mortality (%) was recorded on the tenth day post challenge. Most of the immune parameters including lysozyme activity, superoxide anion production and serum bactericidal activity were significantly (P<0.05) higher on 60 days of feeding of 1.0 g of turmeric per kg of feed. Challenge study indicated 100% and 89% survivability in the group of fish fed with 5.0 and 1.0 g of turmeric per kg of feed respectively. Feeding of turmeric might have maintained long‐term protection in fish by elevating the nonspecific immune system such as Nitroblue tetrazolium (NBT), lysozyme and serum bactericidal activity. The result showed that turmeric at a dose of 1.0 g kg?1 feed for 60 days provided the greatest protection to pathogen challenge.  相似文献   
6.
A 5-year-old, male German shepherd dog was evaluated for a 5-week history of vomiting, diarrhea, lethargy, and weight loss. In abdominal radiographs, there was an unusual corrugated appearance within a loop of intestine. Sonographically, this loop also had a similar corrugated appearance with alternating hyperechoic and hypoechoic bands. Lymph nodes within the abdomen and thorax were enlarged, and a thoracic mass was also detected. Ultrasound-guided fine-needle aspirates of the mesenteric lymph nodes were highly suggestive of lymphoma. After postmortem examination, a diagnosis of multicentric lymphoma with involvement of the gastrointestinal tract was made.  相似文献   
7.
The 13C-octanoic acid breath test (OABT) may be a useful non-invasive method for assessing the rate of gastric emptying in dogs. The aim of this study was to determine whether an association exists between body size and rate of gastric emptying in dogs. Fifty-five dogs ranging from 6 to 39 kg were recruited and rate of gastric emptying was assessed using the OABT. The time to peak 13CO2 excretion (tmax) and half-dose recovery time (t1/2) were calculated. The OABT was simple to perform and well tolerated by the dogs. Mean (sd) tmax was 2.67 hours (0.6) and mean t1/2 was 3.38 hours (0.79). Inter-individual variation in the rate of gastric emptying was 23.3 per cent for t1/2 and 22.5 per cent for tmax. No association was detected between the rate of gastric emptying and body surface area, mass, age, sex or test operator. The OABT may be a useful non-invasive and non-radioactive test for assessment of the rate of gastric emptying in dogs in clinical practice.  相似文献   
8.
9.
RATIONALE FOR THE STUDY: The aims of the study, conducted as a student research project in the 2004-5 session, were to develop an interactive, online computer-aided learning (CAL) package on the topic of small-animal husbandry; to validate the resource as a suitable lecture replacement for first-year veterinary students; and to raise awareness of current guidelines and legislation relating to small-animal housing among local catteries and kennels and in the wider community. METHODOLOGY: Quantitative feedback was collected from student and teaching staff using paper-based questionnaires. Qualitative feedback was gathered from open questionnaire responses and through focus-group discussions with students. Student examination marks were compared for 2004 and 2005, allowing a comparison of student performance before and after the replacement of the traditional lecture with the CAL package. Ethical approval for the study was granted by the faculty's Ethics Committee. RESULTS AND CONCLUSIONS: The CAL package on small-animal housing was well received by teaching staff and students; student performance in examinations improved after the introduction of the CAL program, suggesting that it provides a suitable alternative to didactic teaching. The creation and distribution of the CAL package on CD-ROM and its availability via the Internet are intended to contribute to small-animal welfare education in local catteries and kennels and further afield. The package sets a precedent for the development of more Internet-based, student-authored CAL packages in the future, providing additional resources for independent learning.  相似文献   
10.
International Aquatic Research - The effects of α-melanocyte-stimulating hormone (α-MSH) on calcium metabolism were examined with goldfish. The scales on the left side of goldfish bodies...  相似文献   
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