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41.
Ching-Hao Chang  MD    Yuan-Li Liao  MD    Hong-Shang Hong  MD  Ph  D 《Dermatologic surgery》2003,29(7):775-779
BACKGROUND: Cutaneous metastasis from adenoid cystic carcinoma of the salivary gland is very rare. OBJECTIVE: To present an unusual case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. METHODS: A 63-year-old woman with multiple subcutaneous nodules on the abdomen and a gradually enlarged mass over the right parotid area was examined. A skin biopsy was taken from one of the abdominal nodules. RESULT: Skin biopsy demonstrated the characteristic histopathologic features of metastatic adenoid cystic carcinoma. A subsequent computerized tomography of the head and neck revealed a huge soft tissue mass involving the right parotid gland. Computerized tomography of the chest revealed extensive nodular pleural thickening, and pleural biopsy also showed typical histopathologic features of metastatic adenoid cystic carcinoma. All of these results are consistent with the diagnosis of an adenoid cystic carcinoma of the right parotid gland with disseminated metastases. CONCLUSION: We report a rare case of cutaneous metastasis from adenoid cystic carcinoma of the right parotid gland. The presentation of cutaneous metastasis is often nonspecific and may mimic benign lesions. Subcutaneous nodules that are rapidly developing or eruptive, are rapidly growing and have stony hardness in nature, have pain or tenderness, and have nonhealing ulceration remind us of the possibility of cutaneous metastases. Dermatologists and dermatologic surgeons should keep the diagnosis of cutaneous metastasis in mind and always perform skin biopsy when encountering these lesions.  相似文献   
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Images in emergency medicine   总被引:1,自引:0,他引:1  
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Using a prospective hospital-based registry, 146 patients with transient ischaemic attack (TIA) were compared with 376 patients with minor first-ever ischaemic stroke with respect to the 3-month risk of subsequent vascular events, in order to clarify the distinctions between the disease entities. All patients were enrolled within 48 h of onset. The risk factor distribution for the two groups was comparable, except that the TIA patients had more previous TIAs. Large artery atherosclerosis (34%) and small vessel occlusion (32%) were the main aetiologies in the TIA group, whereas small vessel occlusion (49%) was the major cause in the stroke group. The 3-month risk of combined endpoints of stroke, myocardial infarction, and vascular death for TIA patients was higher than that for the minor stroke group (15.1% vs. 3.2%; hazard ratio 4.6, 95% confidence interval 2.3-9.3 in multivariate analysis). Large artery atherosclerosis and male sex were the other significant predictors. TIA may demand more urgent management than minor stroke. The fact that aetiology is a predictor, highlights the need for rapid diagnostic tests to establish pathogenesis.  相似文献   
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 To monitor the lead hazards in industries and to investigate the prevalence of elevated blood lead levels (BLLs) in lead-exposed workers, a lead surveillance system (PRESS-BLLs) has been established and operated in Taiwan, Republic of China, since July 1993. A cohort of lead-exposed workers who received a periodic annual health examination at 55 accredited hospital laboratories was constructed. A total of 9807 separate BLL measurements were reported to the system in 1994. The mean BLL was 15.8 μg/dl in male workers and 11.6 μg/dl in female workers. The mean BLL of lead-exposed workers was significantly (P<0.05, z-test) higher than that of the general Taiwanese population (8.6 μg/dl for males and 6.7 μg/dl for females). In addition, the BLLs of 983 (10.0%) workers exceeded the regulatory action level (40 μg/dl for males; 30 μg/dl for females). The workplaces and homes of 57% of the workers with elevated BLLs were thoroughly investigated to determine the sources of lead contamination. These actions identified the causes of elevated BLLs and set up strategies to reduce workers’ lead exposure. The establishment of this occupational lead surveillance system represents a method for monitoring of lead hazards from occupational and environmental settings to prevent lead poisoning. The information acquired from the system can help in the setting up of a priority of prevention and the development of control measures. It is also useful for further monitoring of changes in the BLLs of the lead-exposed-worker cohort. The Health Department of Taiwan can use this information to evaluate the effectiveness of current industrial hygiene practice. Subjects with elevated BLLs have been medically treated and placed on long-term follow-up for sequelae. Received: 2 September 1996/Accepted: 29 November 1996  相似文献   
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The purpose of this study is to develop an evaluation instrument with high feasibility and acceptability, and to quantify the outcome of evaluation, in order to set up an efficient evaluation system. Teaching evaluation with questionnaire by students has been carried out in National Yang-Ming Medical College for two years. With the support of both teachers and students, the system has been established and conducted on a regular basis. The most important purpose of evaluation is to improve the quality of teaching. During the two academic years (Sep. 1986-June 1988) of the program, the overall response rate was 44.5%, the Department of Nursing had the highest response rate, followed by Dentistry, Medicine-Post Graduate, Medical Technology, and Medicine. Taking into consideration of the year and the class size, the regression analysis found that higher year or smaller size of the class had better response rate. The response rates dropped significantly after the first academic year regardless of department or year. A total of 23 classes were included in the evaluation program and 99 courses were evaluated. All questions in the questionnaire used a 0 to 4 ordinal scale, in which 0 (improvement needed) was the low end and 4 (excellent) the high end. The mean score of the seven questions of teaching evaluation was 2.47. As a whole, the students were satisfied with the teaching. As to the categories of courses, clinical courses had better mean score than basic medical courses, and basic medical courses had better mean score than common required courses. To evaluate the effectiveness of the teaching, students' achievement was used as the outcome variable. The most important predictive variable was the method of instruction, followed by the content of lecture such as degree of difficulty of the lecture and cognitiveness of the contents. The above 3 variables explained 76% of the variation of the students' achievement. However, the significant of teachers' speech, performance and attitude were not so influential. Analysis based on the characteristics of the teachers (sex, age, position, and teaching experience), the characteristics of students (department and year), teaching environments (time and place), and the 3 categories of courses (clinical, basic medical and common required courses) showed that all the above variables only explained less then 10% of the variation of the students' achievement.  相似文献   
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The total sequence-specific 1H assignment for the alpha 185-peptide was accomplished by analysis of COSY spectra along with spin-decoupling and confirmatory NOE difference experiments. Some ambiguities in the assignments were successfully addressed utilizing additional peptides with selective amino acid substitutions. The chemical shifts of several of the C alpha H resonances, along with evidence for a slowly exchanging amide at Thr-191 suggest that the alpha 185-peptide may contain a certain amount of non-random coil structure. The role of any such ordered structure in the mechanism of binding to alpha-bungarotoxin remains to be determined. The assignment of the peptide 1H resonances will facilitate the analysis and identification of chemical shift perturbations observed upon formation of the complex between alpha-bungarotoxin and the alpha 185-peptide [7].  相似文献   
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