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41.
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   
42.
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   
43.
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   
44.
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   
45.
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   
46.
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   
47.
The objective of this study was to evaluate the efficacy and tolerability of robenacoxib, a selective cyclooxygenase-2 inhibitor, for the treatment of post-operative pain and inflammation in cats. The study was a prospective, multi-centre, randomised, blinded, non-inferiority design clinical study to compare robenacoxib to meloxicam. Ninety-six cats undergoing surgery at eight centres in Japan were allocated randomly to receive a single s.c. injection of robenacoxib (2 mg/kg, n=67) or meloxicam (0.3 mg/kg, n=29) shortly before induction of anaesthesia. Most cats underwent soft tissue surgery (n=87), mainly ovariectomy (n=68). Post-operative pain and inflammation were assessed at 3, 8 and 22 h after recovery from anaesthesia using numerical rating scales. For the primary efficacy endpoint (total clinician score), robenacoxib had significantly better efficacy than meloxicam, the relative efficacy ratio being 1.47 (95% confidence interval 1.19-1.78, P=0.0003). For the secondary efficacy endpoints, robenacoxib was superior to meloxicam when assessed on the basis of posture, behaviour, pain on palpation and overall pain control, while meloxicam was superior with respect to wound heat. No cat in either group required rescue analgesia therapy. In tolerability assessments, pain during injection and pain and inflammation at the injection site 22 h after recovery from anaesthesia were rated significantly less with robenacoxib compared to meloxicam. Both treatments were well tolerated on the basis of clinical observations and blood tests, with no significant differences between groups. In conclusion, single pre-operative administration of robenacoxib was well tolerated and had superior efficacy to meloxicam in reducing post-operative pain in cats.  相似文献   
48.
Little information is available on the relationship between computed tomography (CT) imaging findings and the pathologic diagnosis of canine hepatic tumors. Our purpose was to clarify the characteristic features of CT findings in liver tumors in dogs. Data from 33 dogs with either a hepatocellular carcinoma, n = 14, hepatocellular adenoma, n = 14, or nodular hyperplasia, n = 5 were summarized from medical records. CT features for each histologic diagnosis were characterized and analyzed statistically. Common findings in hepatocellular carcinoma included central (79%, P = 0.0030) and marginal enhancement (93%, P = 0.00043) in the arterial phase, cyst-like lesions (93%), capsule formation (93%), and hypoattenuation in the portal (86%), and equilibrium phases (93%). Hepatic adenoma was characterized by a characteristic diffuse enhancement pattern during the arterial phase (57%, P = 0.013), which was also found in nodular hyperplasia (60%), but never in hepatocellular carcinoma. Nodular hyperplasia was less likely to have a capsule structure (20%, P = 0.0087). Mass size was significantly smaller in nodular hyperplasia than in hepatocellular carcinoma and hepatic adenoma (P = 0.0033 and 0.038, respectively). Hyperattenuation in the arterial and the portal phase i.e. contrast retention, was more frequent in hepatic adenoma than in the other groups (P = 0.037 and 0.037, respectively). Nodular hyperplasia was more frequently isoattenuating in the equilibrium phase (P = 0.043).  相似文献   
49.
Ecosystem-level assessments of carbon (C) stocks of agroforestry systems are scarce. We quantified the ecosystem-level C stocks of one agroforestry-based oil palm production system (AFSP) and one agroforestry-based oil palm and cacao production system (AFSP+C) in eastern Amazonia. We quantified the stocks of C in four pools: aboveground live biomass, litter, roots, and soil. We evaluated the distribution of litter, roots, and soil C stocks in the oil palm management zones and in the area planted with cacao and other agroforestry species. The ecosystem-C stock was higher in AFSP+C (116.7 ± 1.5 Mg C ha?1) than in AFSP (99.1 ± 3.1 Mg C ha?1). The total litter-C stock was higher in AFSP+C (3.27 ± 0.01 Mg C ha?1) than in AFSP (2.26 ± 0.06 Mg C ha?1). Total root and soil C stocks (0–30 cm) did not differ between agroforestry systems. Ecosystem-C stocks varied between agroforestry systems due to differences in both aboveground and belowground stocks. In general, the belowground-C stocks varied spatially in response to the management in the oil palm and non-oil palm strips; these results have important implications for the monitoring of ecosystem-level C dynamics and the refinement of soil management.  相似文献   
50.
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