OBJECTIVE: To establish intrauterine growth curve for the birth weight of twins on the basis of gestational age. METHODS: The medical records of twin gestations delivered between 1980 and 2001 were reviewed. 610 Twin pairs (1,220 infants) were comprised our study population. The newborns were grouped according to gestational age and the median, 10th, 50th, and 90th percentile birth weight for each gestational week were calculated. Intrauterine growth curve of twins was compared with that of singletons of Wonju Christian Hospital. We studied the differences of birth weights of twins as sex, parity, chorionicity in twins. RESULTS: The birth weights of twins fall below that of singleton after 32-33 weeks. The 50th percentile for twins falls below the 10th percentile for singleton after 37 weeks, and 90th percentile for twins falls below the 50th percentile for singleton. The mean birth weight in male twin infant was heavier than in female twin infant through all gestational week. The mean brith weight in multiparity was heavier than in nulliparity through all gestational week. The mean birth weight in dichorionic twins was heavier than in monochorionic twins through all gestational week. CONCLUSION: We presented twin specific birthweight curve on the basis of gestational age. The growth pattern of twins was different from that of singleton. We recommend the twin specific birthweight curve in the management of twin gestations.
Birth Weight* ; Chorion ; Female ; Gangwon-do ; Gestational Age* ; Humans ; Infant ; Infant, Newborn ; Male ; Medical Records ; Parity ; Parturition* ; Twins*

PURPOSE: This study validated the musculoskeletal model of the human lower extremity by comparative study between calculated muscle parameters through simulation using modified hill-type model and measured muscle parameters through isokinetic exercise. The relationship between muscle forces and moments participated in motion was quantified from the results of simulation. MATERIALS AND METHODS: For simulation of isokinetic motion, a three-dimensional anatomical knee model was constructed using gait analysis. The EMG-force model was used to determine muscle activation level exciting muscles. The modified Hill-type model was used to calculate individual muscle force and moment in dynamic analysis. This method was validated by comparing analytical data with experimental data. RESULTS: The results showed that there was a significant correlation between calculated torques from simulation and measured torque from isokinetic motion experiments (R=0.97). We also found that muscle forces and moments during knee flexion and extension have nonlinearly proportional or inversely proportional relationship, since lower extremity muscles were simultaneously involved in flexion/extension motion and inner/outer rotation. CONCLUSION: We concluded that the simulation by using musculoskeletal model may be a useful mean to predict and recover musculoskeletal-related diseases, and analyze complicated experiment such as clash condition.
Gait ; Humans ; Knee Joint* ; Knee* ; Lower Extremity ; Muscles ; Torque

Purpose: To analyze electrocardiograms (ECGs) of patients with a salt-losing tubulopathy (SLT) and to determine the frequency and risk factors for long QT and arrhythmia. Methods: A total of 203 patients aged <19 years with SLT, specifically Bartter syndrome and Gitelman syndrome, who had a 12-lead ECG were included in this retrospective study. We analyzed the presence of an arrhythmia or prolonged corrected QT (QTc) on ECGs obtained for these patients. Demographic and laboratory data were compared between patients with abnormal and normal ECG findings. Results: Out of the 203 SLT patients, 38 (18.7%) underwent electrocardiography and 10 (40.0%) of 25 patients with inherited SLT had abnormal ECG findings, including prolonged QTc and arrhythmias. The abnormal ECG group had significantly lower serum potassium levels than the normal group (median [interquartile range]: 2.50 mmol/L [2.20–2.83] vs. 2.90 mmol/L [2.70–3.30], p=0.036), whereas other serum chemistry values did not show significant differences. The cutoff level for a significant difference in QTc interval was serum potassium level <2.50 mmol/L. One cardiac event occurred in a 13-year-old boy, who developed paroxysmal supraventricular tachycardia and underwent cardiac ablation. No sudden cardiac deaths occurred in this cohort. Conclusions The incidence of ECG abnormalities in patients with inherited SLT was 40.0%, whereas the ECG screening rate was relatively low (18.7%). Therefore, we recommend ECG screening in patients with inherited SLT, especially in those with serum potassium level <2.50 mmol/L.

OBJECTIVE: The authors have aimed to compare the efficacy of the computed tomography with other study methods, and to investigate if replacement by computed tomography is possible METHODS: From January 1998 to December 2002, 203 cervical cancer patients underwent pre-staging studies including computed tomography. The positive predictive values, negative predictive values, sensitivity, specificity of each method of study were compared. RESULTS: 1. Compared computed tomography with intravenous pyelonephrography. Each values of computed tomography for hydronephrosis or non visualization of kidney were sensitivity 91.7%, specificity 97.8%, positive predictive values 84.6%, negative predictive values 98.9%. 2. Compared computed tomography with cystoscopy. Each values of computed tomography for bladder invasion were sensitivity 90%, specificity 95.8%, positive predictive values 52.9%, negative predictive values 99.4%. 3. Compared computed tomography with sigmoidoscopy. Each values of computed tomography for rectal invasion were sensitivity 80%, specificity 94.4%, positive predictive values 26.6%, negative predictive values 99.4%. CONCLUSION: Rather than routine examination for staging of invasive cervical cancer in all patients, it is more ideal to first take a non invasive technique. then perform on intravenous pyelonephrography, cystoscopy and sigmoidoscopy only in patient showing positive findings of hydronephrosis or non visualization of kidney, bladder or rectal invasion on computed tomography.
Cervix Uteri* ; Cystoscopy ; Female ; Humans ; Hydronephrosis ; Kidney ; Sensitivity and Specificity ; Sigmoidoscopy ; Urinary Bladder ; Uterine Cervical Neoplasms

International migrants could be considered a risk group susceptible to vaccine-preventable diseases. We conducted a measles seroprevalence study among 419 marriage migrant women living in Sinan-gun and Wando-gun, South Jeolla Province, located in the southwestern part of Korea. The overall seroimmunity was 92.8%. The seroimmunity varied considerably according to the country of origin and increased with age. Our current analysis could be valuable in the context of discussions concerning vaccination policies for immigrants in Korea.

PURPOSE: The level of serum prostate-specific antigen (PSA) varies according to both age and race. It is known that the level of PSA increases with age, and that Asians have a lower incidence of prostate cancer and levels of PSA than Caucasians. In this study, the variation in the serum PSA level in samples collected from general populations were used to find an actual standard age-specific PSA reference range for Koreans. MATERIALS AND METHODS: Patients who received serum PSA level check-ups, between November 1998 and July 2005, at 8 domestic hospitals, were selected for the investigation. The PSA levels of 120,439 adult males, aged between 30 and 80 years, were measured, and those lower than 10ng/ml were analyzed. To estimate the increase in the level of serum PSA according to age, a simple linear regression analysis was carried out. RESULTS: The mean PSA level reference ranges according to age were 1.88, 1.92, 2.37, 3.56 and 5.19ng/ml for those in their thirties, forties, fifties, sixties and seventies, respectively. The rates of PSA change were 0.0023, 0.0175 and 0.0499 for those in their forties, fifties and sixties, respectively, indicating the rates of PSA level change increase steady with age, but these increases are greater for those in their fifties and most severe after their sixties. The level of age-specific PSA reference in Korean men was lower than that of men from Western countries. CONCLUSIONS: The age-specific PSA reference levels, as found in pre-existing literature, showed differences between races, with the overall reference levels being low for domestic data. The standard reference level of age-specific PSA for the screening of prostate cancer may be lower in Korean men than those from Western countries.
Adult ; Asian Continental Ancestry Group ; Continental Population Groups ; Humans ; Incidence ; Linear Models ; Male ; Mass Screening ; Prostate-Specific Antigen* ; Prostatic Neoplasms ; Reference Values*