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1.
OBJECTIVE: To determine the location in soft tissues of the calcifications, similar to calcified carotid atheromas, that can be observed radiographically in the cervical region in panoramic radiographs. STUDY DESIGN: In each anatomic cadaver specimen preserved in formol, consisting of the head and neck, radiopaque spheres (made from gutta-percha) were positioned in anatomic structures of the cervical region that can be sites of calcification. For each anatomic structure marked in this way, panoramic radiography was performed, consisting of 17 radiographs. The images obtained were analyzed by 24 examiners who indicated which radiographs, in their opinion, presented the radiopaque reference projected in the region of bifurcation of the carotid artery. Analysis of 2 proportions from agreement and disagreement was used to determine radiopacities that could be confused in panoramic radiographs with calcified atheromas in the carotid artery. RESULTS: The results showed that 75% (18) of the examiners correctly indicated the reference in the bifurcation of the carotid artery and 79.2% (19) indicated a triticeous cartilage as calcified atheroma of the carotid artery. CONCLUSIONS: Calcified atheromas of the carotid artery are not the only features that can produce radiopaque images lateral to the panoramic radiograph; the presence of calcification in the triticeous cartilage also can induce an erroneous diagnosis of calcified carotid atheroma.  相似文献   
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The aim of this study was to investigate cell kinetics and ultrastructural changes during carcinogenesis using a hamster 9,10-dimethyl-1,2-benzanthracene (DMBA)-induced tongue cancer model. Five squamous cell carcinomas, five dysplastic epithelia, seven hyperplastic epithelia, and four normal epithelia were obtained from 21 hamster tongues by applying 1.0% acetone solution of DMBA on the left lingual mucosa after scratching with a root canal broach. Ultrastructural examination revealed that the number of microvilli increased, whereas that of desmosomes decreased during carcinogenesis. Cell proliferation was analyzed by means of 5-bromodeoxyuridine (BrdU) immunohistochemistry and in situ hybridization (ISH) for histone H3 mRNA. The BrdU and histone H3 mRNA labeling indices (LIs) were lowest for normal epithelium, higher for hyperplastic and dysplastic epithelia, and highest for squamous cell carcinoma. Cytoplasmic histone H3 mRNA and nuclear BrdU were localized in virtually identical areas of serial sections. The correlation coefficient for the relationship between these two LIs was 0.97 (P 0.001). These results suggest that the assessment of cell proliferation using H3 mRNA ISH will be a useful technique for investigating biological behavior during carcinogenesis.  相似文献   
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Having an Advance Directive (AD) can help to guide medical decision-making. Asian Americans (AA) are less likely than White Americans to complete an AD. This pilot study investigated the feasibility and efficacy of a church-based intervention to increase knowledge and behavior change related to AD among Chinese and Vietnamese Americans. This study utilized a single group pre- and post-intervention design with 174 participants from 4 churches. Domain assessed: demographics; AD-related knowledge, beliefs, attitudes, and intentions; AD completion; and conversations with a healthcare proxy. Data were analyzed using Chi square and multiple logistic regression techniques. We observed significant increases in participants’ AD-related knowledge, intentions, and a gain in supportive beliefs and attitudes about AD, resulting in 71.8 % AD completion, and 25.0 % having had a proxy conversation. Providing culturally-tailored intervention and step-by-step guidance can help to achieve significant changes in AD related knowledge and behavior in AA church goers.  相似文献   
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Anaplastic large cell lymphoma (ALCL) comprises 10-15% of childhood non-Hodgkin lymphomas (NHL). Systemic ALCL is highly associated with anaplastic lymphoma kinase (ALK) gene translocations with over-expression of ALK protein. We studied ALK rearrangements using fluorescence in situ hybridisation (FISH) and ALK immunohistochemical staining in 43 paediatric systemic ALCLs. FISH (performed on 35 cases) identified a translocation in 29 cases (83%). Immunohistochemistry identified ALK over-expression in 42/43 cases (97%) with the single ALK-negative case demonstrating an ALK rearrangement by FISH, indicating 100% incidence of ALK translocations.  相似文献   
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The effects of L-carnitine (900 mg, p.o. daily) on exercise performance were studied in 12 patients with stable effort angina using a multistage treadmill exercise test. Exercise tests were performed at the end of the placebo period and after 4 and 12 weeks of carnitine therapy. While 12 patients experienced angina during treadmill tests in the placebo period, 2 patients were free of angina after treatment with carnitine. The mean exercise time was 11.4 +/- 0.7 min (mean +/- SE) in the placebo period. This increased significantly to 12.2 +/- 0.5 min (p less than 0.05) after 4 weeks and 12.8 +/- 0.5 min (p less than 0.01) after 12 weeks of treatment with carnitine. The time required for 1 mm ST depression to occur was 6.4 +/- 0.9 min in the placebo period. This increased significantly to 7.6 +/- 0.9 min (p less than 0.01) after 4 weeks and 8.8 +/- 1.0 min after 12 weeks of treatment with carnitine. There was significantly less ST segment depression during the same exercise load after 12 weeks of treatment as compared with that in the placebo period (p less than 0.05). The heart rate and the pressure rate product at the same work load showed no significant difference among the 3 testing periods. The results of this study suggest that L-carnitine may improve exercise tolerance in patients with effort angina.  相似文献   
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While depression has been associated with infertility treatments, it is not routinely assessed in women prior to undergoing in vitro fertilization (IVF) treatment. Findings are mixed regarding the degree to which women report depression prior to IVF. The purpose of this study was to (1) examine response profiles in women preparing for IVF and (2) compare responses to those of postpartum, primary care, and general population groups. Female IVF patients (n?=?321; 19–45 years) completed the Patient Health Questionnaire-9 (PHQ-9) at their first visit. Clinical and demographic characteristics and incidence of major depressive disorder (MDD) and other depressive disorders (ODD) were examined. Overall score distributions of the IVF group were compared to those of local postpartum patients and published primary care and general populations. Demographic or clinical characteristics did not account for response differences within the IVF group. The IVF group had lower incidences of MDD and ODD than a PHQ-9 normative group. Women in the IVF group reported no depressive symptoms significantly more than postpartum, primary care, and general population groups. Women preparing to undergo IVF report fewer symptoms of depression than multiple comparison groups. Specific quality of life measures may be needed to assess distress in this population.  相似文献   
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