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1.
C. O. Onyeaso BDS FWACS M. O. Arowojolu BDS FWACS J. O. Taiwo BDS MSc DDPH RCS Eng 《American journal of orthodontics and dentofacial orthopedics》2003,124(6):714-720
This prospective clinic-based study evaluated the pretreatment periodontal status of the orthodontic patients seen at the University College Hospital, Ibadan, Nigeria, and assessed the relationship between dental aesthetic index (DAI) scores and periodontal status according to community periodontal index of treatment needs (CPITN) scores. One hundred forty five patients-70 (48.3%) males and 75 (51.7%) females from 6 to 45 years (mean 15.8 +/- 7.5)-were seen. World Health Organization (WHO) guidelines were followed in the examination and reporting of the periodontal status, and DAI scores were assessed based on WHO guidelines. The chi-square test was used to determine the association between the DAI and the CPITN scores. Most patients were in the 6-15 (55.9%) or 16-25 (35.9%) age groups. Based on the WHO preferred cumulative calculations of treatment need (TN), 35.2% of the patients had TN 0, 64.9% had TN 1, 24.9% had TN 2, and only 0.7% had TN 3. The relationship between DAI scores and periodontal treatment needs was not statistically significant (P >.05). Although many patients were yet to attain the WHO goal of no more than 1 sextant affected by bleeding or calculus at the age of 15, over one third had satisfactory periodontal health. 相似文献
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Dissociation of GFAP intermediate filaments in EAE: observations in the lumbar spinal cord 总被引:1,自引:0,他引:1
Acute experimental allergic encephalomyelitis (EAE) in the Lewis rat is a cell-mediated autoimmune disease of central nervous system myelin. The lesion has been characterized by breakdown of the blood-brain barrier, edema, and periventricular infiltration of macrophages and lymphocytes. At the early stage of the disease, the astrocytes show a marked increase in immunostaining for glial fibrillary acidic protein (GFAP). A corresponding increase in GFAP content, however, cannot be demonstrated. Electron microscopic examination of the early lesion shows a typical reactive astrocytic response expressed by an enlarged watery cytoplasm, particularly at the level of the processes surrounding neurons and blood vessels and in the neuropil itself. The astroglial processes contain numerous glycogen particles (aggregates and single particles). Glial filaments are also conspicuous and are arranged in small bundles or loose thin filaments adjacent to the bundles. The glial filaments that normally appear as tight bundles have expanded and appear less dense. We suggest that the increase in GFAP immunostaining of the astrocytes in the early lesion is due in part to edema, which causes dissociation of the filaments and thereby exposes more antigenic sites to the antibodies. 相似文献
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Influence of Electromagnetic Fields on Function of Automated External Defibrillators 总被引:3,自引:2,他引:1
Roman Fleischhackl MD Florian Singer MD Wolfgang Nitsche PhD MSc Eng Guenther Gamperl MSc Engineering Bernhard Roessler MD Jasmin Arrich MD Sabine Fleischhackl MD Heidrun Losert MD Fritz Sterz MD Martina Mittlboeck PhD MSc Klaus Hoerauf PhD MD 《Academic emergency medicine》2006,13(1):1-6
Objectives: In this study, the authors tested whether electromagnetic interference (EMI) is able to impair correct electrocardiogram analysis and produce false‐positive shock advice from automated external defibrillators (AEDs) when the true rhythm is sinus. Methods: Nineteen healthy subjects were used to test five AEDs available on the Austrian market in a prospective, open, and sequence‐randomized study. The primary outcome variable was the absolute number of shocks advised in the presence of EMI. The secondary outcome was the number of impaired analyses caused by incorrectly detected patient movements or electrode failure. Results: Of 760 tests run, 18 (2.37%) cases of false‐positive results occurred, and two of five AEDs recommended shocks in the presence of sinus rhythm. Of 760 tests run, no electrode failures occurred. There were 27 occurrences (3.55%) of motion detected by an AED in the presence of strong electromagnetic fields. Conclusions: AED models differ in their response to EMI; it may be useful to consider specific safety requirements for areas with such fields present. Working personnel and emergency medical services staff should be informed about potential risks and the possible need for patient evacuation before AEDs are attached and shock recommendations are followed. 相似文献
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Rapid screening of organosulfur agents for potential chemopreventive activity using the murine NA assay 总被引:1,自引:0,他引:1
The chemopreventive efficacy of 11 organosulfur compounds was assessed using the murine nuclear aberration (NA) assay in C57BL/6J mice. The sulfur compounds were introduced by stomach gavage. Benzo[a]pyrene (BP), which is a carcinogen known to a) undergo biotransformation by pathways mediated by P-450 and b) induce NA in the intestine, was used as the challenge. All animals were killed 48 hours after BP injection, and NA per crypt were scored. The results indicated that several agents were active in inhibiting BP nucleotoxicity to the colon, most notably, allyl mercaptan, benzyl mercaptan, and phenylethyl mercaptan. The NA assay was useful in effectively prescreening certain compounds for potential interactions with chemical carcinogens, thus serving as one indicator of chemopreventive activity. 相似文献