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11.
G Berding H Schliephake G Neumann R Schmelzeisen FW Neukam GJ Meyer KF Gratz H Hundeshagen 《Canadian Metallurgical Quarterly》1996,35(5):156-163
AIM: The aim of this study was early differentiation between uncomplicated and complicated processes of healing in the jaw using bone SPECT. METHODS: Investigations were performed in 40 mandibular fractures and 26 jaws after onlay osteoplasty as well as secondary insertion of implants. Bone SPECT was carried out within 1-2 months and after approximately 4-5 months. The uptake in the jaw was assessed semi-quantitatively using ROI analysis. RESULTS: Fractures with uncomplicated healing showed a decrease of uptake in follow-up, whereas fractures with an infection in the later course showed an increase, resulting in a significantly higher uptake at the follow-up investigation for the latter group. 1-2 months after onlay osteoplasty significantly lower uptake was found in regions with later occurrence of sequestration. In regions with implants in which osseointegration failed, there was significant reduction of uptake initially and significant elevation at the follow-up investigation. CONCLUSION: These results indicate a prognostic relevance of bone SPECT in the evaluation of processes of healing in the jaw. 相似文献
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K Papadakis FI Luks ME De Paepe GJ Piasecki CW Wesselhoeft 《Canadian Metallurgical Quarterly》1997,32(2):347-351
We investigated cell proliferation and cell death in the olfactory epithelium (OE) of mice from birth to maturity using bromodeoxyuridine and terminal deoxynucleotidyl transferase nick end labeling. We show that cell death events and proliferative activity diminish concomitantly with age in the OE. Thus, the age-dependent and coordinate diminution in cell proliferative activity and cell death events may serve to maintain the thickness of the OE as mice mature and age. 相似文献
15.
GJ Grover 《Canadian Metallurgical Quarterly》1997,75(4):309-315
Cancer cells release various antigens, some of which appear in the urine. Oral autourotherapy is suggested as a new treatment modality for cancer patients. It will provide the intestinal lymphatic system with the many tumor antigens against which antibodies may be produced. These antibodies may be pierced through the blood stream and attack the tumor and its cells. 相似文献
16.
AS Jonason S Kunala GJ Price RJ Restifo HM Spinelli JA Persing DJ Leffell RE Tarone DE Brash 《Canadian Metallurgical Quarterly》1996,93(24):14025-14029
The multiple genetic hit model of cancer predicts that normal individuals should have stable populations of cancer-prone, but noncancerous, mutant cells awaiting further genetic hits. We report that whole-mount preparations of human skin contain clonal patches of p53-mutated keratinocytes, arising from the dermal-epidermal junction and from hair follicles. These clones, 60-3000 cells in size, are present at frequencies exceeding 40 cells per cm2 and together involve as much as 4% of the epidermis. In sun-exposed skin, clones are both more frequent and larger than in sun-shielded skin. We conclude that, in addition to being a tumorigenic mutagen, sunlight acts as a tumor promoter by favoring the clonal expansion of p53-mutated cells. These combined actions of sunlight result in normal individuals carrying a substantial burden of keratinocytes predisposed to cancer. 相似文献
17.
Concentrations of 11 trace elements were determined in 56 control and 98 Alzheimer's disease (AD) olfactory bulb, olfactory tract, olfactory trigone, piriform cortex and amygdala specimens by instrumental neutron activation analysis. Iron and zinc were significantly elevated and bromine was significantly depleted in olfactory regions of AD patients, compared with normal age-matched control subjects. Elevated iron could possibly play a role in neuronal degeneration in AD by enhancing reactive free radical formation. 相似文献
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MJ Kania SD Keeling SP McGorray TT Wheeler GJ King 《Canadian Metallurgical Quarterly》1996,66(6):423-432
This study examined risk factors associated with incisor injury in 3396 third and fourth grade school children in Alachua County, Florida. One of six orthodontists completed a standardized examination form for each child to assess severity of incisor injury, gender, age, race, skeletal relationships, morphologic malocclusion, incisor exposure, interlabial gap, TMJ sounds, chin trauma, and history of lower facial trauma. One in five (19.2%) exhibited some degree of incisor injury. This was limited to a single tooth in 73.1% of those with injury, while enamel injury predominated (89.4%). The majority of the injuries (75.4%) were localized in the maxillary arch, with central incisors the most frequently traumatized. Chi-square tests of association indicated that gender, race, school, orthodontist, history of lower facial trauma, chin trauma, profile, and maxillary and mandibular horizontal positions were associated with incisor injury (P < 0.05). Wilcoxon rank sum tests identified differences in age, overjet, time of screening, and interlabial gap between those with and without injury (P < 0.05). Results of logistic regression analyses indicated risk of incisor injury was greater for children who had a prognathic maxilla, a history of trauma, were older, were male, and had greater overjet and mandibular anterior spacing. 相似文献
20.
J Randerson L Cawkwell A Jack JA Child F Lewis N Hall P Johnson P Evans S Barrans GJ Morgan 《Canadian Metallurgical Quarterly》1996,93(1):160-162
Fluorescent polymerase chain reaction (PCR) was used to assay 12 microsatellite markers (APC x 2, DCC, P53 x 2, RB1, NM23, WT1, D6S260, D6S262, D6S281 and TNFa) to look for evidence of microsatellite instability in 40 cases of follicle centre cell lymphoma (FCC). Evidence of novel alleles seen in the tumour tissue but not the normal uninvolved tissue was seen in seven cases (17%). In only two of these cases (5%) was more than one locus involved but in these cases multiple affected loci were seen (4/12 and 7/12 respectively). The detection of microsatellite instability indicates a DNA repair defect such as that which would be predicted to occur in cells with mutated mismatch repair genes, a novel finding in FCC lymphoma. 相似文献