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41.
A simplified mass screening method for methylmercury exposure was developed using methylmercury-volatilizing bacteria from Minamata Bay. Some bacteria can transform methylmercury into mercury vapor. Most mercury in the hair is methylmercury, which is readily extracted with HCl solution. Black spots are formed on X-ray film due to the reduction of Ag(+) emulsion with mercury vapor produced by methylmercury-volatilizing bacteria. By exploiting these characteristics, a screening method was developed, whereby the fur of rats injected with methylmercury chloride formed clear black spots on X-ray film, whereas the fur of rats injected with saline did not. Subsequently, 50 human hair samples were examined using this mass screening method. The method identified people who had high mercury concentration, over 20 microg/g. A few thousand hair samples may be screened in a day using this method because it is rapid, simple, and economical. This method, therefore, enables screening of persons with methylmercury poisoning in mercury-polluted areas.  相似文献   
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PURPOSE: Incidence of loss of activity and death in elderly people living at home were investigated to attempt to determine their relationship to physio-social activities in elderly. METHOD: This longitudinal study of life expectancy and active life expectancies is a thirty-six months follow up study. Loss of activities were classified as follows: Long term (over six months) treatment at home, long term (over six months) admission to hospital or intermediate institute for the elderly, admission to nursing home, and death. Subjects were persons living at home in Ogi, Saga prefecture, aged 70 years or older not requiring help in active daily living (ambulating, bathing, dressing, discharging, eating). RESULTS: 6,274 (male = 2,383, female = 3,891) subjects were followed for thirty six months, and 178 people experienced long term treatment at home, 310 people had long term admission to a hospital or intermediate institute for elderly, 28 people were admitted to a nursing home and 449 people experienced death. The main results were as follows: (1) From the Cox proportional hazards model using the likelihood-ratio method of survival and active life loss, significant hazard ratios for reduction active life expectancy for male were found for age, disability score for ADL, speech disorder, inconvenient bathroom design, with attention to health, and daily activity were associated with extension of active life expectancy. Age, disability score for ADL, speech disorder, inconvenient bathroom design were associated with reduced life expecting, while, attention to health, choosing to undergo regular health examinations, and daily were associated with increased activity in life expectancy. (2) Hazard ratios for reduction active life expectancy for females were age, disability score for ADL, defect of memory deficits, inconvenient design for hallway and stairs. Participating in health examinations, Purpose in life were associated with life expectancy increase. For females were age, disability score for ADL, speech disorder, inconvenient design of bathroom were associated with decrease in life expectancy, while having a person in life was associated with increase in life expectancy. DISCUSSION: Relationship between physio-social activities in elderly is a significant factor in many studies on elderly health. This study suggests that age, disability score for ADL, inconvenient for housing design, active health behavior, daily activities, and Losing a sense of worth in living, affect active life expectancy and life expectancy.  相似文献   
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PURPOSE: Ewing's family tumors (EFTs) display the characteristic fusion gene EWS-Fli1. We have reported EWS-Fli1 may promote the cell cycle progression accompanied by the suppression of the expression of cyclin-dependent kinase inhibitor p27(kip1) in EFT cells. Here, we describe the prognostic and therapeutic relevance of p27 in EFTs. EXPERIMENTAL DESIGN: We examined tumor samples taken from 21 patients with primary EFTs for the expression of p27 protein immunohistochemically and evaluated its correlation with clinical outcome. We also investigated the usefulness of p27 as a therapeutic strategy in vitro and in vivo using p27 expression adenovirus. Finally, we examined the process of EWS-Fli1-mediated reduction of p27 expression. RESULTS: Immunohistochemical analysis showed that a low expression level of p27 protein was related to poor event-free survival in an univariate analysis and that the expression level of p27 correlated more significantly with patient survival than several clinical factors in a multivariate survival analysis. Overexpression of p27 with the adenoviral vector remarkably inhibited the cell growth in all EFT cells tested and further induced apoptosis in the wild-type p53 EFT cells. In vivo studies demonstrated a reduction in tumor growth of EFT xenograft in nude mice treated with the intratumoral injection of p27-expressing adenovirus. EWS-Fli1 did not significantly affect the p27 promoter activity and p27 mRNA levels. However, the challenge of the proteasome inhibitor caused accumulation of p27 protein in EFT cells. These data strongly suggest EWS-Fli1 might attenuate p27 protein level via activation of the proteasome-mediated degradation pathway. CONCLUSIONS: Our findings provide the first evidence of the prognostic relevance of p27 expression in EFTs. We propose p27 as a novel and powerful therapeutic factor for the molecular target therapy of EFTs.  相似文献   
44.
AIM—To evaluate the clinical significance of soluble thrombomodulin and antiendothelial cell antibodies (AECA) in children with Henoch-Schönlein purpura.METHODS—Binding of serum AECA to bovine glomerular endothelial cells was evaluated by enzyme linked immunosorbent assay, cytotoxicity against glomerular endothelial cells by spectrophotometric assay, and soluble thrombomodulin concentrations by sandwich enzyme immunoassay.RESULTS—IgA AECA were detected in seven of 15 patients with Henoch-Schönlein purpura and nephritis, but were not detected in patients without nephritis or in controls. Patients with Henoch-Schönlein nephritis had raised titres of IgA AECA and serum thrombomodulin; severe proteinuria and renal histological changes were associated with raised titres of IgA AECA and raised serum thrombomodulin. No subjects had complement dependent cytotoxicity against glomerular endothelial cells.CONCLUSIONS—High titres of IgA AECA and raised serum thrombomodulin may be clinically useful markers of renal involvement in patients with Henoch-Schönlein purpura.  相似文献   
45.
It is likely that a close association exists between findings obtained by two methods: dobutamine stress echocardiography and 123I-MIBG scintigraphy. Both of these methods are associated with beta-adrenergic receptor mechanisms. This study was conducted to demonstrate the relation between myocardial response to dobutamine stress and sympathetic nerve release of norepinephrine in the failing heart. In 12 patients with heart failure due to idiopathic dilated cardiomyopathy, the myocardial effects of dobutamine stress were evaluated by low-dose dobutamine stress echocardiography: and sympathetic nerve function was evaluated by scintigraphic imaging with iodine-123 [123I] meta-iodobenzylguanidine (MIBG), an analogue of norepinephrine. Echocardiography provided quantitative assessment of wall motion and left ventricular dilation; radiotracer studies with 123I-MIBG provided quantitative assessment of the heart-to-mediastinum (H/M) uptake ratio and washout rate. Results showed that H/M correlated with baseline wall motion (r = 0.682, p = 0.0146), wall motion after dobutamine stress (r = 0.758, p = 0.0043), the change in wall motion (r = 0.667, p = 0.0178), and with left ventricular diastolic diameter (r = 0.837, p = 0.0007). In addition, the 123I-MIBG washout rate correlated with baseline wall motion (r = 0.608, p = 0.0360), wall motion after dobutamine stress (r = 0.703, p = 0.0107), and with the change in wall motion (r = 0.664, p = 0.0185). Wall motion, especially in the myocardial response to dobutamine stress, is related to sympathetic nerve activity in heart failure.  相似文献   
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