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We evaluated the anti-tumor effect of adenoviral vector-mediated p53 gene therapy on the growth of canine osteosarcoma xenografts formed in nude mice. Nude mice were subcutaneously transplanted with cells of 2 P53 mutant canine osteosarcoma cell lines, POS and CHOS. The osteosarcoma xenografts were injected with either an adenoviral vector that expresses canine wild-type P53 (AxCA-cp53) or LacZ (AxCA-LacZ). Tumor growth was significantly inhibited in the xenografts injected with AxCA-cp53 in comparison to those injected with AxCA-LacZ or PBS during the observation period of 27 days. An increase of the amount of p21(WAF1/CDKN1A) mRNA, and the number of apoptotic cells was shown in the tumors injected with AxCA-cp53 in comparison to those injected with AxCA-LacZ or PBS. The present study revealed that the adenoviral vector-mediated p53 gene transfer had an anti-tumor effect in canine osteosarcoma xenografts formed in nude mice.  相似文献   
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To compare the technical difficulty and safety of epidural catheterization between cranial and caudal lumbar region, thirteen dogs were randomly assigned to a cranial lumbar group (group CraL, n=6) or a caudal lumbar group (group CauL, n=6) depending on different epidural sites, and one dog was used as a negative control without catheterization. After general anesthesia, an epidural catheter was advanced 10 cm cranially from the interspace of L1-L2 in group CraL or from lumbosacral space in group CauL. Dogs were euthanized and catheter position and tip location were confirmed by laminectomy. Spinal cord samples were examined by macro- and microscopic observations. Success rate, time taken for epidural space confirmation and catheter insertion were compared, and overall technical difficulty was evaluated subjectively. Epidural catheter was inserted successfully in all dogs. Time needed from needle skin puncture to catheter placement and saline injection was 226 ± 63 and 229 ± 26 sec in groups CraL and CauL without significant differences. Three dogs in group CraL suffered subcutaneous blood, but no spinal cord injuries were found. Subjective evaluation score of the overall technical difficulty was slightly but significantly higher in group CraL than in group CauL (P=0.009). Epidural catheterization in cranial lumbar region could be performed as feasible and safe as that at the caudal lumbar vertebral region in medium or large dogs.  相似文献   
75.
Olfactory ensheathing cells (OECs) have been reported to promote axonal regeneration when transplanted to rodent spinal cord injury models. OECs are available from the olfactory bulb (OB) and olfactory mucosa (OM). Although harvesting OECs from the OM is less traumatic, OECs originating from the OM are less proliferative than those from the OB (OB-OECs). One possible reason for this difference is coexisting fibroblasts. Here, we examined the effect of coculturing either fibroblasts from the OB (OB-Fibs) or fibroblasts from the OM (OM-Fibs) on the proliferation of OB-OECs. Proliferation of OB-OECs was significantly higher in 5:5 coculture with OB-Fibs and in 7:3 and 5:5 cocultures with OM-Fibs than without fibroblasts. These results indicated that coculture with both OB-Fibs and OM-Fibs promoted the proliferation of OB-OECs.  相似文献   
76.
As diamond-producing catalysts, 12 transition metals such as iron, cobalt, and nickel were first reported by General Electric researchers more than 30 years ago. Since then, no additional elemental catalyst has been reported. An investigation of the catalytic action of group V elements is of great interest from the viewpoint of producing an n-type semiconducting diamond crystal. In the present study, diamond was synthesized from graphite in the presence of elemental phosphorus at high pressure and temperature (7.7 gigapascals and 1800 degrees C). Furthermore, single-crystal diamond was grown on a diamond seed crystal.  相似文献   
77.
The identities of the digits of the avian forelimb are disputed. Whereas paleontological findings support the position that the digits correspond to digits one, two, and three, embryological evidence points to digit two, three, and four identities. By using transplantation and cell-labeling experiments, we found that the posteriormost digit in the wing does not correspond to digit four in the hindlimb; its progenitor segregates early from the zone of polarizing activity, placing it in the domain of digit three specification. We suggest that an avian-specific shift uncouples the digit anlagen from the molecular mechanisms that pattern them, resulting in the imposition of digit one, two, and three identities on the second, third, and fourth anlagens.  相似文献   
78.
The centuries-old, self-organizing Muang Fai community irrigation institution in northern Thailand has high potential in illustrating exemplary practices in irrigation cost sharing. This paper examines the cost sharing structure of the Pongsak Muang Fai Irrigation System in Mae Hong Son Province and its relationship with the system water management and sustainability. Results show that this primitive and high cost system accepts costs of the weir, the entire length of main ditch, not only the individually related ditch sections, and the management as common costs that should be equally shared so that it can gather sizeable membership to support the system. The capacity of this small scale run-of-the-river irrigation system with no river flow limitation is a simple summation of all determined farm intake capacities. The maintenance cost of the system every year depends on how much water should be diverted and conveyed, hence the use of “relative” scale of each farm intake capacity as the basis for sharing cost in the wet season paddy farming. Such structure is directly related to the water management under which every intake shall be served with continuous supply without permitting mid-canal water check-up and the members prefer to take collective action to keep enough water supply without leaving any room for suspicion of unfair water distribution. The direct relationship makes the members understand the purpose of payment and be willing to share the costs which are transparently estimated in easily understood terms and clearly de-aggregated into categories.  相似文献   
79.
ObjectiveThe objective of this study was to evaluate the influence of heart rate (HR) on myocardial function assessed by two-dimensional speckle-tracking echocardiography (2D-STE) in healthy dogs.AnimalsThirteen healthy beagle dogs.MethodsAnimals were anesthetized and HR was controlled with right atrial pacing. Myocardial function of each dog was assessed using 2D-STE at pacing rates of 120, 140, 160, and 180 bpm.ResultsAll strain and strain rate variables in the longitudinal, circumferential, and radial directions were not significantly different between pacing rates. Peak early diastolic torsion rate at 180 bpm was significantly increased compared with that at 120 bpm (P = 0.003).ConclusionTorsion rate in early diastole was elevated at 180 bpm, which may reflect improved myocardial relaxation with higher HR. Changes in left ventricular torsion during tachycardia may play an important role in preserving stroke volume in the presence of shortened ejection and filling times.  相似文献   
80.
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   
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