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61.
In several primates and carnivores, pronation/supination angles of the forearm skeleton were examined, and it is thought that a larger angle is useful to acquire dexterous behaviors in feeding and/or life style, including climbing. In this study, the pronation/supination angles in Asiatic black, brown and polar bears were nondestructively examined. These specimens were classified as adult or non-adult. Three or four carcasses of each group of Asiatic black and brown bears were used for CT analysis, whereas only one adult polar bear was used. The forearms were positioned within the gantry of a CT scanner in both maximally supinated and pronated states. Extracted cross-sectional CT images of two positions were superimposed by overlapping the outlines of each ulna. The centroids of the radii were detected, and then the centroid of each radius and the midpoint of a line which connects between both ends of the surface of each radius facing the ulna, were connected by lines to measure the angle of rotation as an index of pronation/supination. In adult brown and polar bears, the angles were smaller as compared with the other groups (Asiatic black and non-adult brown bears). Asiatic black and non-adult brown bears can climb trees, whereas adult brown bears and polar bears cannot. This suggests that the pronation/supination angle is related to arboreal activity in Ursidae.  相似文献   
62.
Although it has been reported that dietary lycopene, the main carotenoid in tomato, improved drug-induced nephropathy, there are no reports on the effect of orally administered lycopene on the in vivo renal reducing (i.e., antioxidant) ability. The radiofrequency electron paramagnetic resonance (EPR) method is a unique technique by which the in vivo reducing ability of an experimental animal can be studied. In this study, the in vivo changes in the renal reducing ability of rats orally administered lycopene were investigated using a 700 MHz EPR spectrometer equipped with a surface-coil-type resonator. Rats were fed either a control diet or a diet containing lycopene. After 2 weeks, in vivo EPR measurements were conducted. The renal reducing ability of lycopene-treated rats was significantly greater than that of the control. This is the first verification of in vivo antioxidant enhancement via dietary lycopene administration.  相似文献   
63.
A simple test for detecting decline of cognitive ability in aged dogs is needed in modern society. We used a basic place-selection test to develop a new test to assess cognitive ability in dogs, using 25 house dogs. Three covered bowls were placed in front of the subject. One of them was the correct bowl, from which the subject was rewarded with a food treat when he/she chose it. If the subject made an incorrect selection, he/she was returned to the starting point and the trial was repeated. Cognitive ability was assessed by the number of errors needed to fulfill the criterion. We found a significantly high correlation between the dogs’ ages and the number of error trials, suggesting that age-related cognitive dysfunction may reliably be assessed by the documented place-learning test.  相似文献   
64.
The purpose of this observational study was to determine the characteristic computed tomographic (CT) myelography findings of cervical vertebral stenotic myelopathy (CVSM) lesions in Thoroughbred horses. A total of 23 Thoroughbred horses (age range, 155–717 days on CT examination; mean, 410.9 days) were analyzed. All 23 Thoroughbred horses underwent unenhanced radiography, radiographic myelography, and CT myelography. Unenhanced radiographs were observed the presence of cervical vertebral malalignment and osseous lesions. Radiographic myelograms were observed for signs of cervical spinal cord compression; additionally, CT myelograms were used to detect cervical vertebral osseous lesions. Ventral compressions were frequently observed in the cranial cervical vertebrae (C2–C4), whereas dorsal compressions were frequently observed in the caudal cervical vertebrae (C5–C7). Furthermore, osseous lesions of the caudal articular process developed more frequently than those of the cranial articular process. CT myelography in Thoroughbred horses is a useful method for detecting CVSM changes.  相似文献   
65.
Platelet-rich plasma (PRP) was administered to cattle with hoof defects (10-mm drill hole) to promote sole defect healing. Two types of gels were prepared. One was a mixed gel [compound of gelatin microspheres (GM) incorporated with PRP and alginate] and was used for the test group, while the other was an alginate gel used for the control group. Each hole was filled with one of these gels. The drill hole depth, pressure pain, and hardness of the regenerated tissue were measured for 3 weeks after treatment. These measurements improved significantly in the test group than in the control group. The results suggest that a compound of GM incorporated with PRP and alginate had a hoof-regenerating effect in cattle.  相似文献   
66.
The purpose of this study was to investigate the minimum effective dose of recombinant canine interferon-γ (rCaIFN-γ) for the treatment of dogs with atopic dermatitis (AD). Thirty-four dogs with AD from 17 animal hospitals in Japan were administered half or one-fifth of the approved rCaIFN-γ dose of 10 000 units/kg, three times a week for 4 weeks, followed by once weekly for an additional 4 weeks. Pruritus, excoriation, erythema and alopecia were evaluated and scored by the investigators on weeks 2, 4, 6, 8 and 12. The efficacy rate (number of excellent cases + number of good cases/total number of cases) at week 8 in the 2000 units/kg group was 36.4% for pruritus, 36.4% for excoriation, 45.5% for erythema and 36.4% for alopecia. In contrast, in the 5000 units/kg group, the efficacy rate was 64.3% for pruritus, 57.1% for excoriation, 78.6% for erythema and 78.6% for alopecia. The efficacy rate of the 5000 units/kg group was high for all signs evaluated and comparable to that of the 10 000 units/kg group reported in a previous study. The results of this study showed that 2000 units/kg of rCaIFN-γ is less effective than 5000 units/kg to treat dogs with AD, and the efficacy of the 5000 units/kg dose is comparable to that of 10 000 units/kg at week 8.  相似文献   
67.
3-nitrotyrosine, a product of tyrosine nitration, is a useful indicator of oxidative damage. We modified the previously reported HPLC-electrochemical detection (ECD) method: specifically, a through-type porous carbon electrode was used as a reducing electrode instead of the mercury-gold amalgam electrode, because the response of the latter changes over time. A combination of reverse-phase HPLC and electrochemical detector passed through -800 mV reduction potential and subsequently under +250 mV oxidation potential allows measurement of 3-nitrotyrosine. The detection limit of this assay was less than 10 fmol. In mice to which lipopolysaccharide (LPS) was administered intraperitoneally, plasma 3-nitrotyrosine levels were elevated, corresponding to LPS dosage. These findings suggest that the improved HPLC-ECD method can be used as a specific and sensitive assay of biological 3-nitrotyrosine and can be applied clinically.  相似文献   
68.
The aim of the study was to assess the effects of changing acquisition parameters used for high-resolution in vivo magnetic resonance (MR) microscopy on image quality and scan time. The head or abdomen of 11 normal and 1 glioblastoma-bearing anesthetized BALB/c mice were imaged using a high-resolution 7.0-Tesla magnet. Scan parameters such as matrix size (MTX), slice thickness (ST), number of excitations (NEX), pulse sequence type including repetition time (TR) and echo time (TE), respiratory gating, and intraperitoneal contrast medium administration were altered to assess their actual effect on signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) as compared to calculated effects. As expected, SNR increased with increasing ST or NEX and with decreasing MTX. However, although the empirical increase in SNR was similar to that expected for increased ST, it was less than that anticipated for increasing NEX or decreasing MTX. Increasing NEX and applying respiratory gating both increased SNR and reduced the image degradation associated with respiratory motion in images of the abdomen. Intraperitoneal contrast medium administration produced a marked increase in CNR in the subject with the implanted glioblastoma, suggesting that this route is satisfactory for the enhancement of lesions disrupting the blood-brain barrier. The consequence of improving image quality in terms of spatial and contrast resolution is increased scan time. However, the actual increase in SNR when altering acquisition parameters may not be as much as predicted by theory.  相似文献   
69.
Plasma vitamin C (ascorbic acid + dehydroascorbic acid) concentration is a good index of the nutritional status of vitamin C. However, the methodologies for storage and analyses have not been investigated in bovine plasma. The validity of an analytical method for bovine plasma using high performance liquid chromatography (HPLC) with a spectrophotometric detector was examined. Exogenous dehydroascorbic acid was almost completely converted to ascorbic acid during the preparation for analysis with a reducing reagent, dithioerythritol. The analytical recoveries of ascorbic acid were high. Ascorbic acid was not detected after treatment with ascorbic acid oxidase. Thus, the specificity of this method is considered to be high. Although vitamin C was stable in plasma treated by dithioerythritol at ?20°C for 6 days, vitamin C in untreated plasma significantly decreased during 3‐day storage at ?20°C. These results indicate that the HPLC method is suitable for the determination of plasma vitamin C in cattle and that the storage conditions are important for determination of plasma vitamin C. Plasma vitamin C concentration ranged between 1.49 mg/L and 3.33 mg/L in fattening cattle. This result suggests that fattening cattle show large individual variation in plasma vitamin C concentration.  相似文献   
70.
Our objective in this study was to examine the effect of gelatin hydrogel (GH) sheets containing basic fibroblast growth factor (bFGF) on healing of proximal sesamoid bone transverse fractures in the horse. Ten healthy adult Thoroughbreds were used. The lateral proximal sesamoid bone of the left forelimb and the medial proximal sesamoid bone of the right forelimb were osteotomized, while the horses were under general anesthesia, and subsequently repaired by lag screw fixation using a single 4.5-mm cortical screw. A GH sheet containing 100 μg of bFGF was then sutured to the synovial membrane adjacent to the osteotomized proximal sesamoid bone. In the control group, the fracture was fixed with a lag screw, and the articular capsule was sutured. Fracture healing was assessed by radiographic examination once a week for 16 weeks after the operation. Radiographic examination of bone healing revealed significantly lower demineralization of the fracture line in the GH sheet-treated group than in the control group. The rate of demineralization of the fracture line in the GH sheet-treated group was significantly lower than that in the control group at 2, 4, and 8 weeks after the operation. In this study, we demonstrated that the use of a GH sheet containing bFGF promotes healing of proximal sesamoid bone fracture in the horse. Therefore, it is believed that this treatment strategy would be useful for quick recovery from bone fracture in the horse.  相似文献   
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