• Imaging Science in Dentistry
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• v.36 no.1
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• pp.17-24
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• 2006

Purpose : The objective of this study was to investigate the effect of TMJ disc displacement on the TMJ disc configuration and surrounding osseous structure. Materials and Methods : The proton density and 72-weighted MR images of 57 TMJs were retrospectively studied. These TMJs were divided into three groups according to the anterior disc displacement status on MR sagittal images, those were the normal, anterior disc displacement with reduction (ADWR), anterior disc displacement without reduction (ADWOR). The frequency of disc configuration and surrounding bony change, the border status between articular disc and retrodiscal tissue were investigated according to the positional change of articular disc. Results : There were significant statistical differences of chi-square statistics of TMJ disc configurational type between normal and ADWR/ADWOR group, respectively. Surrounding bony change frequently appeared in ADWOR and a statistically significant difference of chi-square statistics of bony change frequency between normal and ADWOR group was observed. Conclusion : These results suggested that the disc configuration and bony change of TMJ are strongly related to TMJ disc displacement.

• Neonatal Medicine
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• v.25 no.3
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• pp.131-135
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• 2018

Hyponatremia is defined as a plasma sodium concentration of <135 mEq/L. It is a common electrolyte imbalance in newborns. We report the case of a term neonate with cleft lip, cleft palate, imperforate anus, normal male karyotype, and chronic hyponatremia. On the 4th day of life, he showed hyponatremia (plasma sodium concentration 130 mEq/L) with low serum osmolality (275 mOsm/kg), high urine sodium (116.7 mEq/L), and high urine osmolality (412 mOsm/kg). His thyroid and adrenal functions were normal. Despite intravenous and oral sodium supplementation and hydrocortisone treatment, hyponatremia persisted. Brain magnetic resonance imaging showed normal results. He was diagnosed as having reset osmostat, a rare subtype of the syndrome of inappropriate secretion of antidiuretic hormone characterized by a subnormal threshold for antidiuretic hormone secretion, with hypotonic hyponatremia.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.6
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• pp.591-598
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• 1984

The results of measurements showing normal vibrations and rubbing noise generated during unlubricated smooth sliding between metal surfaces are presented. The measurements were made on pin-on-disc type apparatus instrumented with piezoelectric acceleration transducers and microphones. Spectral analysis of the both signals up to frequency of 10kHz indicates that they are closely correlated. The major components of both signals in this frequency range are primarily associated with the normal contact vibrations which are excited by surface irregularities being swept through the contact region during sliding. As an approximation to the seismic input of surface irregularities, an effective surface wavenumber spectrum was assumed in the form of an inverse vibration and noise measurements for a number of surface finishes and mean loads. The predominant frequency component of which levels of the normal vibration and noise are close to overall levels of the both signals is induced by contact resonance between the two bodies and its frequency can be calculated from the Hertzian theory.

• Clinics in Shoulder and Elbow
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• v.18 no.3
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• pp.172-193
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• 2015

Nowadays shoulder ultrasound is commonly used in the assessment of shoulder diseases and is as accurate as magnetic resonance imaging in the detection of several pathologies. Operator dependence is the main disadvantage of shoulder ultrasound. After adhering to a strict examination protocol, good knowledge of normal anatomy and pathologic processes and an awareness of common pitfalls, it can be used as a focused examination providing rapid, real-time diagnosis, and treatment by ultrasound-guided interventions in desired clinical situations. Also shoulder ultrasound can help the surgeon decide whether treatment will be surgical or nonsurgical. If arthroscopy is planned, sonographic findings help to counsel patients regarding surgical and functional outcomes. If a nonsurgical approach is indicated, ultrasound can be used to follow patients. This review article presents the examination techniques, the normal sonographic appearances and the main pathologic conditions found in shoulder ultrasound. And also addresses a simplified approach to scanning and ultrasound-guided intervention. Knowledge of optimal techniques, normal anatomy, dynamic maneuvers, and pathologic conditions is essential for optimal performance and interpretation of images.

• Proceedings of the KSMRM Conference
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• 2003.10a
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• pp.20-20
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• 2003

Purpose： To investigate the difference of fractional anisotropy (FA) values between 6- and 25-direction diffusion tensor images (DTI) in normal adult brain. Materials and Methods： DTI was peformed in 28 normal subjects (15 subjects with 6-direction, 13 subjects with 25-direction) in a 1.5 T MR system. DTI was done with SE-EPI sequence with TR/TE/NEX 10000/84/1, 5mm slice thickness and b=1000 s/mm2. FA values were measured from 8 different anatomical locations which included both cerebral peduncles, both posterior limbs of the internal capsules, both corona radiata, genu and splenium of the corpus callosum. Statistical difference of FA was tested between 6-and 25-direction DTI.

• Clinical and Experimental Pediatrics
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• v.54 no.1
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• pp.40-44
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• 2011

We present a case of tacrolimus-induced encephalopathy after successful kidney transplantation. An 11-year-old girl presented with sudden onset of neurologic symptoms, hypertension, and psychiatric symptoms, with normal kidney function, after kidney transplantation. The symptoms improved after cessation of tacrolimus. Magnetic resonance imaging (MRI) showed acute infarction of the middle cerebral artery (MCA) territory in the right frontal lobe. Three days later, she had normal mental function and maintained normal blood pressure with left hemiparesis. Follow-up MRI was performed on D19, showing new infarct lesions at both cerebral hemispheres. Ten days later, MRI showed further improvement, but brain single photon emission computed tomography (SPECT) showed mild reduction of uptake in both the anterior cingulate gyrus and the left thalamus. One month after onset of symptoms, angiography showed complete resolution of stenosis. However, presenting as a mild fine motor disability of both hands and mild dysarthria, what had been atrophy at both centrum semiovale at 4 months now showed progression to encephalomalacia. There are two points of interest in this case. First, encephalopathy occurred after administration of tacrolimus and improved after discontinuation of the drug. Second, the development of right-side hemiplegia could not be explained by conventional MRI; but through diffusion tensor imaging (DTI) and diffusion tensor tractography (DTT) of white matter tract, visualization was possible.

• Imaging Science in Dentistry
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• v.36 no.2
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• pp.73-79
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• 2006

Purpose : To describe the MRI findings of the antero-superior attachment of the disc in patients with internal derangement. Materials and Methods : One hundred fifty-six MR images from 40 normal subjects and 55 abnormal subjects were classified into three study groups of normal, anterior disc displacement with reduction and anterior disc displacement without reduction. On both closed- and open-mouth proton density sagittal images, the depiction of the antero-superior attachment of the disc and its demarcation from the disc were evaluated in three cuts of lateral, central and medial one thirds of the condyle. Results : The depiction of antero-superior attachment was more frequent by the order of normal, anterior disc displacement with reduction and anterior disc displacement without reduction groups, and the significant differences were found on lateral cut of the closed images and lateral and central cuts of the open images. In study for the demarcation between the antero-superior attachment and the disc the lateral cut of the closed images and all three cuts of the open images showed significant differences. Conclusion : Open images are useful to show the difference in depiction of the antero-superior attachment of the disc among the TMJ groups.

• YAKHAK HOEJI
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• v.42 no.5
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• pp.494-499
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• 1998

As part of a drug discovery program to discover more effective platinum-based anticancer drugs, a series of platinum complexes of 1,2-bis(diphenylphosphino)ethane(1,2-diaminopro pane)platinum(II)dinitrate (KHPC-070) has been evaluated in vitro against various tumor cell lines and normal kidney cells. The structure of this new compound was determined by elemental analysis, infrared spectroscopy (IR) and $^{13}carbon$ nuclear magnetic resonance (NMR). With the use of nine tumor cell lines, KHPC-070 exhibited a comparable cytotoxic to cisplatin. The cytotoxicity of KHPC-070 in normal cells was quite less than that of cisplatin using 3-(4.5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide (MTT) and [$^3H$]-thymidine uptake tests in rabbit renal proximal tubular cells and human renal cortical cells. Based on these results, KHPC-070 is considered to have more selective cytotoxicity toward cancer cells than normal human/rabbit kidney cells.

• Journal of Oral Medicine and Pain
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• v.23 no.3
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• pp.281-288
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• 1998

The authors treated a 30-years old female patient who visited the Department of Oral Medicine, PNUH due to the chief complaint of limitation of mouth opening. The magnetic resonance imaging following clinical examination was used for establishing an accurate and reliable diagnosis and the patient was diagnosed as having anterior disc displacement without reduction in the right joint and anterior disc displacement with reduction in the left joint. For managing acute anterior disc displacement without reduction, mandible manipulation was applied first focusing on pain control and then stabilization appliance was used for maintenance of joint stabilization. With time, the sign and symptom was remarkably reduced and an active exercise program was recommended to maintain of normal muscle length, increase joint range of motion and develop normal coordination arthrokinematics. As a result of treatment, the patient did not complain discomfort of normal daily activities and it was difficult to consider that the displace disc was not reduced completely, but the improvement in range of motion and joint mobility were remarkably found. Therefore, an exercise program should be considered to maintain joint mobility and be effective as a self-care.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.71-77
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• 2006

This study introduces the seismic qualification of safety related equipments for nuclear power plants to verify the possibility of resonance in regard to the operating speed and the structural integrity due to external piping nozzle loads as well as seismic dynamic loads using El-Centro earthquake, which was occurred in the 1940's previously. As a first step, it is necessary to investigate the natural frequency of the vertical mixed flow pump in order to determine whether static or dynamic equipment comparing with seismic cut-off frequency, 33hz. Also the normal mode analysis was carried out with the introduction of seismic redesign straint at the middle of vertical pump to increase the natural frequency. In terms of structural integrity, the application of static analysis with normal, upset and faulted nozzle loads event was presented for the comparison of material allowable stress. Also the dynamic analysis was performed to show the design adequacy through the application to the case of El-Centro earthquake.