The results of reoperative valve replacement can be improved if appropriate analysis for the risk of reoperation was achieved. The purpose of our study was to analyze the results of reoperations for failure of bioprosthesis, and to define the risk factors in high-risk populations for reoperative procedures. Material and Method The series of 46 consecutive patients who had undergone first reoperative replacement for failed bioprosthesis between 1993 and 2001 were reviewed retrospectively. Mean age was 42 $\pm$ 12 years, mean body surface area was 1.52 $\pm$0.15 $m^2$. The reoperative procedure comprised of 36 MVR, 8 DVR, and 2 AVR. The first operation comprised of 2 DVR, 1 AVR, and 43 MVR. Factors which were choose to assess a predictor of results in reoperative valve replacement were sex, old age(>60 years), early age at first operation(<30 years), long interval between first and redo operation(.15years), poor NYHA functional class(>3), LV dysfunction(LVEF<45%), long operation time(>8hours), endocarditis, combined procedures, and renal insufficiency, Result : Overall mortality was 4.3%(2 cases). The risk factors that influenced postoperative complications and unexpected postoperative results were lower ejection fraction(p=0.012), older age(p=0.045), endocarditis(p=0.023), long operation time above 8 hours(p=0.027). There was no statistically significant factor influencing hospital mortality. Conclusion : No factor influenced the mortality. Better results could be achieved if reoferation was performed carefully in poor left ventricular function, old aged patient, and with endocarditis. Effort to shorten the operation time would be helpful on postoperative results.
This study examined the reproducibility of nutrient intakes estimated by the 24-hour recall method in a prospective cohort study (Longitudinal study of aging and health monitoring of Korean elderly) of middle-aged volunteer subjects (42 males and 49 females) in the Seoul area. The three-day 24-hour recall was administered twice at an interval of approximately 6 months. The first data were collected and a corrective procedure was performed by interviewing of the subjects and a trained dietitian. The second data were collected by mail from the subjects without the performance of any corrective procedure. The mean age of the subjects was 53.5 $\pm$ 9.6 for the males and 52.2 $\pm$ 8.9 for the females. The subjects who had above college education were 95% in the case of the males and 60% in the case of the females. The characteristics of the male subjects in this study were that they were highly educated and held professional jobs and were from the middle or upper class. Comparing the first and second 24-hour recall data, the second data showed relatively lower intakes of all nutrients, except vitamin A, vitamin Bi and cholesterol. There was no difference in the nutrients of the first and the second data with respect to vitamin A, vitamin B$_1$ and cholesterol in the males and calcium, iron, sodium, vitamin A, vitamin B$_1$, vitamin B$_2$ and cholesterol in the females. This data may indicate that the 24 hour retail method without a dietitian's help may result in lower reporting of the subject's intakes. The men had a tendency to remember less than the women. Pearson's correlation coefficients with unadjusted nutrient intakes values were ranged from 0.24 to 0.66. When energy intake was adjusted, there was a slight increase (from 0.26 to 0.71). Intra-class correlation coefficients with nutrient-unadjusted values ranged from 0.22 to 0.66, and the energy-adjusted values were ranged from 0.23 to 0.69. The weighted Kappa statistical values ranged from 0.10 to 0.40. On the average,46.3% of the subjects who were found in the lowest quartile of the nutrient intake levels based on the first 24-hour recall, were in the lowest quartile based on the second 24-hour recall. Therefore, there was a low reproducibility between the first and the second 24-hour recall. We should examine the factors influencing low reproducibility. Also, strategies should be developed to maximize the reliability of the assessment, with regard to portion-size training and telephone validation. (Korean J Community Nutrition 8(4) : 603∼609, 2003)
Objectives: The aim of this study was to analyze the reliability of the Korean language version of the Research Diagnostic Criteria for Temporomandibular Disorders(RDC/TMD) axis II questionnaire among TMD patients. Methods: The Korean version of the RDC/TMD questionnaire was distributed to 154 TMD patients(31 men, 123 women) who visited Seoul National University Dental Hospital. The test-retest reliability was also assessed among the same subjects with a one- or two-week time interval. The subjects did not receive any form of therapy until the retest administration was completed. Results: The internal consistency reliability of pain intensity, disability score, jaw disability, and psychosocial status were 0.92, 0.94, 0.68, and 0.94, respectively using the Cronbach's alpha coefficient of the 1st test. Test-retest reliability coefficients of each items of the questionnaire ranged from 0.40 to 0.94 assessed with kappa value, and the intra-class correlation coefficient(ICC) for each subscale ranged from 0.81 to 0.93. Test-retest reliability coefficient of the graded chronic pain(GCP) scale was 0.63. Conclusions: The Korean language version of RDC/TMD axis II questionnaire demonstrated good reliability. It can be used as a valuable instrument for the analyses of the psychosocial aspects of the TMD patients in Korea.
In this study, South Korea is divided into 5 zones and is studied about the analysis of time-regional distribution of previpitation frequency and rainfall intensity in Korea. In the previpitation frequency analysis, the basic data groups of 39 stations were selected. The diagram of previpitation frequency was drawn, and the time-regional distribution of precipitation frequency was analized. In the rainfall intensity analysis, the basic data groups of 36 stations were selected. The probable rainfall, I-D-F curve, and regression equation between 24hr. and 10min.-18hr. areal depth were obtained. The results of this study are following; 1) The precipitation class of max. recurrence probability in every season except summer was commonly (1) 1-5mm, (2) 0.1-1mm, (3) 5-10mm in order. 2) The zone of max. recurrence frequency owing to the precipitation class was zone II in precipitation frequency of below 20mm, zone IV in precipitation frequency of 30-40mm, zone I in precipitation frequency of above 70mm for a year. 3) The recurrence probability of precipitation in Korea can be represented to the equation of exponential function; $$W(x)=e^{\alpha+\beta}$$ 4) The first and third zones were expected heavy rain for the short and long duration. 5) The I.D.F. curves were drawn, and established that the time interval for the least deviation of I.D.F curve is 10~40min., 40min. -4hr., 4~24hr. 6) The regression equations of areal mean depth between 24hr. and 10min.-18hr. for each zone were obtained. 7)The probable rainfall of 36 points were calculated.
Kim, Do-Yun;Jang, Byung-Jun;Yoon, Hyun-Goo;Park, Jun-Seok;Yook, Jong-Gwan
The Journal of Korean Institute of Electromagnetic Engineering and Science
/
v.18
no.6
s.121
/
pp.602-611
/
2007
In this paper, the forward link of UHF RFID system is modeled in accordance with the EPCglobal class 1 generation 2(EPCglobal C1G2) UHF Radio-Frequency Identity protocol specification at $860{\sim}960MHz$. Based on the constructed model, characteristics on the forward link signal for the EPCglobal C1G2 RFID reader are simulated with the help of a MATLAB softwarein order to extract the design parameters of a transmit digital filter which meets the Korean RFID regulations. Herein, the forward link model is consisted of PIE source coding, transmit digital filter, modulation, local oscillator, and antenna. From the simulation results, the ranges of three design parameters(roll-off factor, cutoff frequency, the number of tabs) for transmit digital filter are obtained with different modulation techniques and the Tari(type a reference interval) values. Finally, DSB/SSB-ASK modulation technique can not satisfy the EPCglobal C1G2 specification when Tari equals to $6.25{\mu}sec$ in a multiple-reader environment. Consequently this paper can provide a guideline for design parameters of a RFID reader as well as the basic scheme of analyzing frequency interference problems in RFID environments, including multiple-reader and dense-reader environments.
Lee, Jae-Geun;Beom, Jong Wook;Choi, Joon Hyouk;Kim, Song-Yi;Kim, Ki-Seok;Joo, Seung-Jae
Journal of Cardiovascular Imaging
/
v.26
no.4
/
pp.217-225
/
2018
BACKGROUND: In patients with acute heart failure (AHF), diastolic dysfunction, especially pseudonormal (PN) or restrictive filling pattern (RFP) of left ventricle (LV), is considered to be implicated in a poor prognosis. However, prognostic significance of diastolic dysfunction in patients with ischemic heart disease (IHD) has been rarely investigated in Korea. METHODS: We enrolled 138 patients with IHD presenting as AHF and sinus rhythm during echocardiographic study. Diastolic dysfunction of LV was graded as ${\geq}2$ (group 1) or 1 (group 2) according to usual algorithm using E/A ratio and deceleration time of mitral inflow, E'/A' ratio of tissue Doppler echocardiography and left atrial size. RESULTS: Patients in group 1 showed higher 2-year mortality rate ($36.2%{\pm}6.7%$) than those in group 2 ($13.6%{\pm}4.5%$; p = 0.008). Two-year mortality rate of patient with LV ejection fraction (LVEF) < 40% ($26.8%{\pm}6.0%$) was not different from those with LVEF 40%-49% ($28.0%{\pm}8.0%$) or ${\geq}50%$ ($13.7%{\pm}7.4%$; p = 0.442). On univariate analysis, PN or RFP of LV, higher stage of chronic kidney disease (CKD) and higher New York Heart Association (NYHA) functional class were poor prognostic factors, but LVEF or older age ${\geq}75$ years did not predict 2-year mortality. On multivariate analysis, PN or RFP of LV (hazard ratio [HR], 2.52; 95% confidence interval [CI], 1.09-5.84; p = 0.031), higher stage of CKD (HR, 1.57; 95% CI, 1.14-2.17; p = 0.006) and higher NYHA functional class (HR, 1.81; 95% CI, 1.11-2.94; p = 0.017) were still significant prognostic factors for 2-year mortality. CONCLUSIONS: PN or RFP of LV was a more useful prognostic factor for long-term mortality than LVEF in patients with IHD presenting as AHF.
Yahya Alwatari;Devon C. Freudenberger;Jad Khoraki;Lena Bless;Riley Payne;Walker A. Julliard;Rachit D. Shah;Carlos A. Puig
Journal of Chest Surgery
/
v.57
no.2
/
pp.160-168
/
2024
Background: Data on perioperative outcomes of emergent versus elective resection in esophageal cancer patients requiring esophagectomy are lacking. We investigated whether emergent resection was associated with increased risks of morbidity and mortality. Methods: Data on patients with esophageal malignancy who underwent esophagectomy from 2005 to 2020 were retrospectively analyzed from the American College of Surgeons National Surgical Quality Improvement Program database. Thirty-day complication and mortality rates were compared between emergent esophagectomy (EE) and non-emergent esophagectomy. Logistic regression assessed factors associated with complications and mortality. Results: Of 10,067 patients with malignancy who underwent esophagectomy, 181 (1.8%) had EE, 64% had preoperative systemic inflammatory response syndrome, sepsis, or septic shock, and 44% had bleeding requiring transfusion. The EE group had higher American Society of Anesthesiologists (ASA) class and functional dependency. More transhiatal esophagectomies and diversions were performed in the EE group. After EE, the rates of 30-day mortality (6.1% vs. 2.8%), overall complications (65.2% vs. 44.2%), bleeding, pneumonia, prolonged intubation, and positive margin (17.7% vs. 7.4%) were higher, while that of anastomotic leak was similar. On adjusted logistic regression, older age, lower albumin, higher ASA class, and fragility were associated with increased complications and mortality. McKeown esophagectomy and esophageal diversion were associated with a higher risk of postoperative complications. EE was associated with 30-day postoperative complications (odds ratio, 2.39; 95% confidence interval, 1.66-3.43; p<0.0001). Conclusion: EE was associated with a more than 2-fold increase in complications compared to elective procedures, but no independent increase in short-term mortality. These findings may help guide data-driven critical decision-making for surgery in select cases of complicated esophageal malignancy.
Lukovic, Z.;Uremovic, M.;Konjacic, M.;Uremovic, Z.;Vincek, D.
Asian-Australasian Journal of Animal Sciences
/
v.20
no.2
/
pp.160-165
/
2007
Dispersion parameters for the number of piglets born alive were estimated using a repeatability and random regression model. Six sow breeds/lines were included in the analysis: Swedish Landrace, Large White and both crossbred lines between them, German Landrace and their cross with Large White. Fixed part of the model included sow genotype, mating season as month-year interaction, parity and weaning to conception interval as class effects. The age at farrowing was modelled as a quadratic regression nested within parity. The previous lactation length was fitted as a linear regression. Random regressions for parity on Legendre polynomials were included for direct additive genetic, permanent environmental, and common litter environmental effects. Orthogonal Legendre polynomials from the linear to the cubic power were fitted. In the repeatability model estimate of heritability was 0.07, permanent environmental effect as ratio was 0.04, and common litter environmental effect as ratio was 0.01. Estimates of genetic parameters with the random regression model were generally higher than in the repeatability model, except for the common litter environmental effect. Estimates of heritability ranged from 0.06 to 0.10. Permanent environmental effect as a ratio increased along a trajectory from 0.03 to 0.11. Magnitudes of common litter effect were small (around 0.01). The eigenvalues of covariance functions showed that between 7 and 8 % of genetic variability was explained by individual genetic curves of sows. This proportion was mainly covered by linear and quadratic coefficients. Results suggest that the random regression model could be used for genetic analysis of litter size.
Objectives: As quality of work-life (QWL) among nurses affects both patient care and institutional standards, assessment regarding QWL for the profession is important. Work-related Quality of Life Scale (WRQOLS) is a reliable QWL assessment tool for the nursing profession. To develop a Chinese version of the WRQOLS-2 and to examine its psychometric properties as an instrument to assess QWL for the nursing profession in China. Methods: Forward and back translating procedures were used to develop the Chinese version of WRQOLS-2. Six nursing experts participated in content validity evaluation and 352 registered nurses (RNs) participated in the tests. After a two-week interval, 70 of the RNs were retested. Structural validity was examined by principal components analysis and the Cronbach's alphas calculated. The respective independent sample t-test and intra-class correlation coefficient were used to analyze known-group validity and test-retest reliability. Results: One item was rephrased for adaptation to Chinese organizational cultures. The content validity index of the scale was 0.98. Principal components analysis resulted in a seven-factor model, accounting for 62% of total variance, with Cronbach's alphas for subscales ranging from 0.71 to 0.88. Known-group validity was established in the assessment results of the participants in permanent employment vs. contract employment (t = 2.895, p < 0.01). Good test-retest reliability was observed (r = 0.88, p < 0.01). Conclusion: The translated Chinese version of the WRQOLS-2 has sufficient validity and reliability so that it can be used to evaluate the QWL among nurses in mainland China.
Objectives: This study analyzed the associations of hypertension (HTN) with symptoms and diagnosis of depression by income level among Korean adults. Methods: This study was based on the 2010-2017 Korea National Health and Nutrition Examination Survey data; a total of 29 425 adults (aged 20 years or older) were analyzed. HTN was defined as a systolic blood pressure ≥140 mmHg, diastolic blood pressure ≥90 mmHg, or use of hypertensive medications. Depression symptoms were evaluated based on a questionnaire about depression-related symptoms. A depression diagnosis was defined based on questionnaire responses indicating that a participant had been diagnosed with depression. Household income was divided into higher or lower income ranges based on the median income of the participants. Multiple logistic regression analyses were performed to assess the associations between HTN and depression symptoms/diagnosis in the higher-income and lower-income groups. Results: In the higher-income group, the odds ratio (OR) for the association between HTN and depression symptoms was 1.15 (95% confidence interval [CI], 0.97 to 1.37), and the OR for the association between HTN and depression diagnosis was 1.41 (95% CI, 1.13 to 1.76). In the lower-income group, the OR for the association between HTN and depression symptoms was 1.18 (95% CI, 1.04 to 1.34), whereas the OR for the association between HTN and depression diagnosis was 0.82 (95% CI, 0.70 to 0.97). Conclusions: The associations of HTN with symptoms and diagnosis of depression differed by income level.
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