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141.
Determinations of gastric emptying time (GET) and small intestinal transit time (SITT) are useful in detecting gastrointestinal motility disorders and partial obstructions of the pylorus or small intestine. Barium-impregnated, polyethylene radiopaque spheres with diameters of 1.5 mm and 5.0 mm have been developed for quantitative assessment of gastrointestinal transit.
The purpose of this study was to evaluate GET and SITT using these radiopaque spheres in 10 healthy cats. The cats were randomly assigned to 1 of 3 treatment groups: fasted, fed, and fed plus sedation (acetylpromazine maleate 0.10 mg/kg subcutaneously). A repeated measures study design was used.
The mean GETs of 50%, 75%, and 90% of the 1.5-mm and the 5-mm spheres in the unfed cats were 0.36, 0.58, and 0.74 hours, and 0.41, 0.68, and 1.02 hours, respectively. These values were significantly (P ±.05) more rapid than the GETs of 50%, 75%, and 90% of the 1.5-mm and 5-mm spheres of either the sedated fed cats (4.39, 5.68, 6.65 and 5.15, 5.99, 6.91 hours) or the unsedated fed cats (6.43, 8.12, 9.06 and 7.49, 8.49, 9.22 hours).
The mean GETs of 50% and 75% of the 1.5-mm and 5-mm and of 90% of the 1.5-mm spheres were significantly ( P ±.05) more rapid in sedated than in unsedated fed cats. The GET of 50% of the 1.5-mm spheres was significantly more rapid ( P ±.05) than that of the 5-mm spheres in the fed cats. The mean SITTs, which ranged from 2.25 to 3.05 hours, were not significantly different ( P > .05) among the treatment groups or between the 1.5-mm and 5-mm spheres.
The GET of spheres given to fasted cats is significantly more rapid than that of fed cats. Subcutaneous injection of acetylpromazine speeds GET in fed cats. The SITT of small and large spheres was not influenced by feeding or by acetyl-promazine injection.  相似文献   
142.
Examination of three forest soils from Malaysia using the soil incubation technique suggests that nitrification was not inhibited in these oligotrophic soils. Nitrification rates were between 40 and 750 ngN produced g?1 dry weight soil day?1 of incubation. Addition of phenolic metabolites (tannic acid) and leaf filtrates from hill and lowland forest litter did not significantly inhibit nitrification. Addition of sucrose (1% w/w carbon source) decreased nitrification but not ammonification.  相似文献   
143.
Explants were prepared from skeletal muscle tissue from 5 nondystrophic pups and from 5 pups with X-linked muscular dystrophy; pups were 2 to 17 weeks old. A serial reexplant method resulted in optimal cell density with minimal fibroblast growth. Cultures were examined daily by use of phase-contrast microscopy; differentiated (post-fusion) cultures were examined by electron microscopy. Moderate nuclear pleomorphism and cell clustering were observed in cultures of normal and dystrophic muscle cells. Cultures were maintained to 27 days after plating. Minimal myofilament synthesis was observed in multinucleate cells from nondystrophic and dystrophic pups, but spontaneous contraction of myotubes was not observed during this period. Differences in growth, fusion, or differentiation of myogenic cells into multinucleate cells and myotubes were not found between dystrophic and normal muscle.  相似文献   
144.
Two anthelmintics with known insecticidal action (ivermectin and closantel) and one with no recorded effect on insects (levamisole) were tested to evaluate their effects on buffalo fly (Haematobia irritans exigua). Blood from animals given closantel or levamisole had no significant effect on mortality of buffalo flies in an in-vitro assay. In contrast, blood from animals given ivermectin showed a dose-dependent effect on the mortality of buffalo flies. At 24 h after one injection of the recommended dose of ivermectin, 98% of the flies applied to cattle in an in-vivo assay are killed. Blood from cattle injected with ivermectin killed 95% of flies 8 d after injection and still killed 15% of flies at 18 days after injection. Surviving flies laid almost no eggs and this effect on flies was significant up to 33 d after injection. The results indicate that ivermectin may be useful to control buffalo fly populations in the field.  相似文献   
145.
It has been suggested that the liver may be a major site for irreversible degradation of low-density lipoprotein (LDL). The disappearance of autologous (125)I-labeled LDL from plasma was compared in intact and in hepatectomized swine. Contrary to expectations, the rate of irreversible removal of LDL from plasma was increased rather then decreased by hepatectomy. These studies suggest that the liver is not a major site for LDL removal. We propose further that the liver (or some function requiring an intact liver) may affect the metabolism of LDL in a manner that prolongs its lifetime in the plasma compartment.  相似文献   
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148.
The van der Waals picture focuses on the differing roles of the strong short-ranged repulsive intermolecular forces and the longer ranged attractions in determining the structure and dynamics of dense fluids and solids. According to this physical picture, the attractive interactions help fix the volume of the system, but the arrangements and motions of molecules within that volume are determined primarily by the local packing and steric effects produced by the repulsive forces. This very useful approach, its limitations, and its successful application to a wide variety of static and dynamic phenomena in condensed matter systems are reviewed.  相似文献   
149.
Dental, oral, and maxillofacial diseases are some of the most common problems in small animal veterinary practice. These conditions create significant pain as well as localized and potentially systemic infection. As such, the World Small Animal Veterinary Association (WSAVA) believes that un- and under treated oral and dental diseases pose a significant animal welfare concern. Dentistry is an area of veterinary medicine which is still widely ignored and is subject to many myths and misconceptions. Effective teaching of veterinary dentistry in the veterinary school is the key to progression in this field of veterinary medicine, and to the improvement of welfare for all our patients globally. These guidelines were developed to provide veterinarians with the information required to understand best practices for dental therapy and create realistic minimum standards of care. Using the three-tiered continuing education system of WSAVA, the guidelines make global equipment and therapeutic recommendations and highlight the anaesthetic and welfare requirements for small animal patients. This document contains information on common oral and dental pathologies, diagnostic procedures (an easily implementable and repeatable scoring system for dental health, dental radiography and radiology) and treatments (periodontal therapy, extractions). Further, there are sections on anaesthesia and pain management for dental procedures, home dental care, nutritional information, and recommendations on the role of the universities in improving veterinary dentistry. A discussion of the deleterious effects of anaesthesia free dentistry (AFD) is included, as this procedure is ineffective at best and damaging at worst. Throughout the document the negative effects of undiagnosed and/or treated dental disease on the health and well-being of our patients, and how this equates to an animal welfare issue, is discussed.  相似文献   
150.
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