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991.
Radon is likely the second most common cause of lung cancer after smoking. We estimated the lung cancer risk due to radon using common risk models. Based on national radon survey data, we estimated the population-attributable fraction (PAF) and the number of lung cancer deaths attributable to radon. The exposure-age duration (EAD) and exposure-age concentration (EAC) models were used. The regional average indoor radon concentration was 37.5 95 Bq/m3. The PAF for lung cancer was 8.3% (European Pooling Study model), 13.5% in males and 20.4% in females by EAD model, and 19.5% in males and 28.2% in females by EAC model. Due to differences in smoking by gender, the PAF of radon-induced lung cancer deaths was higher in females. In the Republic of Korea, the risk of radon is not widely recognized. Thus, information about radon health risks is important and efforts are needed to decrease the associated health problems.

Graphical Abstract

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992.
The aim of this study was to investigate the whole picture regarding pregnancy, prenatal care, obstetrical complications, and delivery among disabled pregnant women in Korea. Using the data of National Health Insurance Corporation, we extracted the data of women who terminated pregnancy including delivery and abortion from January 1, 2010 to December 31, 2010. Pearson''s chi-square test and Student-t test were conducted to examine the difference between disabled women and non-disabled women. Also, to define the factors affecting inadequate prenatal care, logistic regression was performed. The total number of pregnancy were 463,847; disabled women was 2,968 (0.6%) and 460,879 (99.4%) were by non-disabled women. Abortion rates (27.6%), Cesarean section rate (54.5%), and the rate of receiving inadequate prenatal care (17.0%), and the rate of being experienced at least one obstetrical complication (11.3%) among disabled women were higher than those among non-disabled women (P < 0.001). Beneficiaries of Medical Aid (OR, 2.21) (P < 0.001) and severe disabled women (OR, 1.46) (P = 0.002) were more likely to receive inadequate prenatal care. In conclusion, disabled women are more vulnerable in pregnancy, prenatal care and delivery. Therefore, the government and society should pay more attention to disabled pregnant women to ensure they have a safe pregnancy period up until the delivery.

Graphical Abstract

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993.
994.
This study aimed to evaluate the validity of the ages and stages questionnaire in Korean (ASQ 1st edition, Korean Questionnaires, Seoul Community Rehabilitation Center, 2000) for premature infants. The study population consisted of 90 premature infants born between January 1, 2005, and December 31, 2011, who were tested using the ASQ (Korean) and Bayley Scales of Infant Development (BSID) (II) at a corrected age of 18-24 months. The validity of the ASQ (Korean) using cut-off values set at < -2 SD was examined by comparing it to the BSID (II) components, namely, the mental developmental index (MDI) or psychomotor developmental index (PDI), which were both set at < 85. The calculation of the sensitivities, specificities, positive predictive values, and negative predictive values of the ASQ (Korean) components revealed that they detected infants with neurodevelopmental delay with low sensitivity and positive predictive values, however, the communication domain showed moderate correlations with MDI. The failure in more than one domain of the ASQ (Korean) was significantly correlated with the failure in MDI. The ASQ (Korean) showed low validity for screening neurodevelopmentally delayed premature infants.

Graphical Abstract

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995.
996.
Cosmetic facial filler-related ophthalmic artery occlusion is rare but is a devastating complication, while the exact pathophysiology is still elusive. Cerebral angiography provides more detailed information on blood flow of ophthalmic artery as well as surrounding orbital area which cannot be covered by fundus fluorescein angiography. This study aimed to evaluate cerebral angiographic features of cosmetic facial filler-related ophthalmic artery occlusion patients. We retrospectively reviewed cerebral angiography of 7 patients (4 hyaluronic acid [HA] and 3 autologous fat-injected cases) showing ophthalmic artery and its branches occlusion after cosmetic facial filler injections, and underwent intra-arterial thrombolysis. On selective ophthalmic artery angiograms, all fat-injected patients showed a large filling defect on the proximal ophthalmic artery, whereas the HA-injected patients showed occlusion of the distal branches of the ophthalmic artery. Three HA-injected patients revealed diminished distal runoff of the internal maxillary and facial arteries, which clinically corresponded with skin necrosis. However, all fat-injected patients and one HA-injected patient who were immediately treated with subcutaneous hyaluronidase injection showed preserved distal runoff of the internal maxillary and facial arteries and mild skin problems. The size difference between injected materials seems to be associated with different angiographic findings. Autologous fat is more prone to obstruct proximal part of ophthalmic artery, whereas HA obstructs distal branches. In addition, hydrophilic and volume-expansion property of HA might exacerbate blood flow on injected area, which is also related to skin necrosis. Intra-arterial thrombolysis has a limited role in reconstituting blood flow or regaining vision in cosmetic facial filler-associated ophthalmic artery occlusions.  相似文献   
997.
Asbestos related pleuropulmonary disease has been emerging health problem for recent years. It can cause variable clinical symptoms and radiological abnormalities. However, there has been no report for their characteristics in subjects who were environmentally exposed to asbestos. We reviewed the CT images of 35 people who were environmentally exposed to asbestos in Chungnam province, Korea. The study result showed high incidence of pleural plaque and pulmonary fibrosis on chest CT (94% and 77%, respectively). The common CT findings of lung parenchymal lesions were as follows: centrilobular opacities (94%), subpleural dot-like or branching opacities (80%), interlobular septal thickening (57%), intralobular interstitial thickening (46%), parenchymal bands (43%) and subpleural curvilinear line (29%). There were no significant differences in the prevalence of pulmonary fibrosis and pleural plaques according to sex, age and duration of exposure. In conclusion, pleural plaque and pulmonary fibrosis are common asbestos-related CT finding in the exposed people. Asbestos related lung parenchymal CT findings in the participants with environmental exposure show similar to those observed in the occupational exposure.  相似文献   
998.
To determine the change in pesticides used during suicide attempts after the 2012 paraquat (PQ) ban, we evaluated the annual number of suicide attempts by pesticide ingestion between 2011 and 2014. We extracted demographic, clinical outcome, and pesticide class data from the medical records of 1,331 patients that attempted suicide by pesticide ingestion. Pesticides were sorted into 5 groups: herbicides, insecticides, fungicides, other pesticides, and combined pesticides. Each group was subdivided into various classes based on publications by the respective Resistance Action Committees. The chi-square test for trends was used to compare the annual incidence of categorical variables. The total number of suicide attempts decreased each year, from 399 in 2011 to 245 in 2014. Simultaneously, PQ ingestion decreased from 253 patients in 2011 to 60 in 2014. The proportion of PQ to pesticides also decreased from 63.4% in 2011 to 24.5% in 2014. Furthermore, the rate of decrease in the proportion of PQ to all herbicide categories increased by calendar year. In conclusion, there is a significant trend in increased annual number of suicides and proportion of suicides using glyphosates and glufosinates versus total herbicides. However, the number of suicide attempts using glyphosate and glufosinate is lower than that using PQ. The ratio of persons completing suicide to those attempting suicide after pesticide ingestion has decreased every year after the PQ ban.

Graphical Abstract

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999.

Objectives

The extracapsular spread (ECS) of metastatic lymph nodes is associated with aggressive tumor behavior, and is regarded as a major risk factor for local recurrence in patients with head and neck squamous cell carcinoma. However, the significance of ECS of metastatic lymph nodes has not been well established in well-differentiated thyroid carcinoma. The purpose of this study was to examine this question.

Methods

A retrospective review was performed of 335 patients with papillary thyroid carcinoma who underwent total thyroidectomy with lymph node dissection from April 2001 to December 2009. We analyzed various clinical characteristics, pathologic factors, and the size, number, and ECS of foci in metastatic lymph nodes.

Results

On pathologic review, 201 of the patients (56.6%) had lymph node metastasis. This was significantly related to age and tumor size. ECS was noted in 64 of these 201 patients (31.8%), and was significantly related to male gender, tumor size, presence of extrathyroidal extension, metastatic lymph node size, and focus size. Recurrence occurred in 13 patients (3.9%), and the presence of ECS was significantly related to recurrence.

Conclusion

ECS of metastatic lymph nodes is an important prognostic factor for loco-regional recurrence in papillary thyroid carcinoma.  相似文献   
1000.

Objectives

The aims of this study were to find and compare the effect of directional (DIR) processing of two different hearing aids via both subjective and objective methods, to determine the association between the results of the subjective and objective evaluations, and to find out individual predictive factors influencing the DIR benefit.

Methods

Twenty-six hearing aid users fitted unilaterally with each two different experimental hearing aid performed modified Korean Hearing in Noise Test (K-HINT) in three DIR conditions; omnidirectional (OMNI) mode, OMNI plus noise reduction feature, fixed DIR mode. In order to determine benefits from DIR benefit within a hearing aid and compare performance of the DIR processing between hearing aids, a subjective questionnaire was administrated on speech quality (SQ) and discomfort in noise (DN) domain. Correlation analysis of factors influencing DIR benefit was accomplished.

Results

Benefits from switching OMNI mode to DIR mode within both hearing aids in K-HINT were about 2.8 (standard deviation, 3.5) and 2.1 dB SNR (signal to ratio; SD, 2.5), but significant difference in K-HINT results between OMNI and OMNI plus noise reduction algorithm was not shown. The subjective evaluation resulted in the better SQ and DN scores in DIR mode than those in OMNI mode. However, the difference of scores on both SQ and DN between the two hearing aids with DIR mode was not statistically significant. Any individual factors did not significantly affect subjective and objective DIR benefits.

Conclusion

DIR benefit was found not only in the objective measurement performed in the laboratory but also in the subjective questionnaires, but the subjective results was failed to have significant correlation with the DIR benefit obtained in the K-HINT. Factors influencing individual variation in perceptual DIR benefit were still hard to explain.  相似文献   
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