• Journal of Korean Academy of Oral and Maxillofacial Radiology
• /
• v.22 no.1
• /
• pp.43-53
• /
• 1992

The purpose of this study was to investigate the effects of irradiation on the microvascular structure of the submandibular gland in rats. For this study, 110 male rats were singly irradiated with the dose of 10Gy or 20Gy to their neck region by 6MV X-irradiation and sacrificed on the 1st, 3rd, 7th, 14th and 28th day after irradiation. The author observed distribution and structural changes of the microvasculature in rat submandibular glands using a scanning electron microscope by forming vascular resin casting. The author observed ultrastructural changes of the endothelial cells using a transmission electron microscope, and also histologic changes using a light microscope at Hematoxylin and Eosin staining and PAS staining process. The results of the irradiation effects on the microvasculature in rat submandibular gland were as follows: By light microscopic examination, the dilation of small vessels were observed until the 7th day after irradiation. After then, the vascular constriction and decrease in number of small vessels were noticed. Changes were greater on 20Gy irradiated group than on lOGy irradiated group. The reaction to PAS staining at acinar cells was decreased just after irradiation, but gradually recovered with days. There was no specific difference between two irradiated groups. By scanning electron microscopic examination, general findings on the two irradiated groups were similar. The dilation of conduits and meandering were observed on the 3rd day after irradiation. Decrease of capillary density and blunt ended small vessels were appeared on the 7th day after irradiation. After that, findings of the tortuous and twisted vascular running and coarseness of capillary lumen were increased. Changes were greater on 20Gy irradiated group than on l0Gy irradiated group. By transmission electron microscopic examination, increase of the formation of cytoplasmic process was observed on the 3rd day after irradiation. After that, swelling of endothelial cell and bridge formation of cytoplasmic processes were also observed, but destruction of endothelial cell and loss of basement membrane were observed only on 20Gy irradiated group on the 28th day after irradiation.

• Korean Journal of Materials Research
• /
• v.10 no.7
• /
• pp.493-498
• /
• 2000

The effects of RRA treatment on the microstructures and mechanical properties of 7050 Al alloy were investigated by differential scanning calolimetry, transmission electron microscopy, microhardness measurement and electrical conductivity. The hardness of 2nd-step aged specimen at $175^{\circ}C$ was decreased to mimimum value and increased to a peak hardness, and then re-decreased with retrogression treatment. It was found that the hardness of 2nd-step aged specimen was further increased by 3rd step aging treatment($120^{\circ}C$x24h). The initial decrease in hardness during 2nd-step aging was due to the partial dissolution of pre-existing GP zone, the major precipitation hardening phase at T6 condition. It was confirmed that the major precipitation hardening phase at 3rd-step aging was GP zone and η' phase. The electrical conductivity increased continually through 2nd-step and 3rd-step aging treatment. It was conclude that the optium 2nd-step aging condition was at $175^{\circ}C$ for 50min by considering the hardness and electrical conductivity.

• Journal of Ginseng Research
• /
• v.39 no.2
• /
• pp.169-177
• /
• 2015

Background: Ginsenoside Rd (GSRd), one of the most abundant ingredients of Panax ginseng, protects the heart via multiple mechanisms including the inhibition of $Ca^{2+}$ influx.We intended to explore the effects of GSRd on L-type $Ca^{2+}$ current ($I_{Ca,L}$) and define the mechanism of the suppression of $I_{Ca,L}$ by GSRd. Methods: Perforated-patch recording and whole-cell voltage clamp techniques were applied in isolated rat ventricular myocytes. Results: (1) GSRd reduced $I_{Ca,L}$ peak amplitude in a concentration-dependent manner [half-maximal inhibitory concentration $(IC_{50})=32.4{\pm}7.1{\mu}mol/L$] and up-shifted the current-voltage (I-V) curve. (2) GSRd ($30{\mu}mol/L$) significantly changed the steady-state activation curve of $I_{Ca,L}$ ($V_{0.5}:-19.12{\pm}0.68$ vs. $-6.26{\pm}0.38mV$; n = 5, p < 0.05) and slowed down the recovery of $I_{Ca,L}$ from inactivation [the time content (${\zeta}$) from 91 ms to 136 ms, n = 5, p < 0.01]. (3) A more significant inhibitive effect of GSRd ($100{\mu}mol/L$) was identified in perforated-patch recording when compared with whole-cell recording [$65.7{\pm}3.2%$ (n = 10) vs. $31.4{\pm}5.2%$ (n = 5), p < 0.01]. (4) Pertussis toxin ($G_i$ protein inhibitor) completely abolished the $I_{Ca,L}$ inhibition induced by GSRd. There was a significant difference in inhibition potency between the two cyclic adenosine monophosphate elevating agents (isoprenaline and forskolin) prestimulation [$55{\pm}7.8%$ (n = 5) vs. $17.2{\pm}3.5%$ (n = 5), p < 0.01]. (5) 1H-[1,2,4]Oxadiazolo[4,3-a]-quinoxalin-1-one (a guanylate cyclase inhibitor) and N-acetyl-$\small{L}$-cysteine (a nitric oxide scavenger) partly recovered the $I_{Ca,L}$ inhibition induced by GSRd. (6) Phorbol-12-myristate-13-acetate (a protein kinase C activator) and GF109203X (a protein kinase C inhibitor) did not contribute to the inhibition of GSRd. Conclusion: These findings suggest that GSRd could inhibit $I_{Ca,L}$ through pertussis toxin-sensitive G protein ($G_i$) and a nitric oxide-cyclic guanosine monophosphate-dependent mechanism.

• The Journal of Korean Academy of Prosthodontics
• /
• v.43 no.2
• /
• pp.232-247
• /
• 2005

Purpose. The purposes of this investigation were to discover the possibility of clinical application in the areas of dental implants and bone grafts by investigating the bone formation histologically around specimen which was depending on the intensity of magnetic field of neodymium magnet inside of the specimens. Material and method. 1. Measurement of magnetic intensity - placed the magnet inside of the specimen, and measured the intensity of magnetic field around the 1st thread and 3rd thread of specimen 20 times by using a Gaussmeter(Kanetec Co., Japan). 2. Surgical Procedure - Male rabbit was anesthetised by constant amount of Ketamine (0.25ml/kg) and Rompun (0.25ml/kg). After incising the flat part of tibia, and planted the specimens of titanium implant, control group was stitched without magnet, while experimental groups were placed a magnedisc 500(Aichi Steel Co., Japan) or magnedisc 800(Aichi Steel Co., Japan) into it, fixed by pattern resin and stitched. 3. Management after the surgery - In order to prevent it from the infection of bacteria and for antiinflammation, Gentamycin and Ketopro were injected during 1 week from operation day, and dressed with potadine. 4. Preparation of histomorphometric analysis - At 2, 4 and 8 weeks after the surgery, the animals were sacrificed by excessed Ketamine, and then, specimens were obtained including the operated part and some parts of tibia, and fixed it to 10% of PBS buffer solution. After embedding specimens in Technovit 1200 and B.P solution, made a H-E stain. Samples width was 75$\mu$m . In histological findings through the optical microscope and using Kappa image base program(Olympus Co. Japan), the bone contact ratio and bone area ratio of each parts of specimens were measured and analyzed. 5. Statistical analysis - Statistical analysis was accomplished with Mann Whitney U-test. Results and conclusion. 1. In histomorphometric findings, increased new bone formation was shown in both control & experimental groups through the experiment performed for 2, 4 & 8 weeks. After 4 weeks, more osteoblasts and osteoclasts with significant bone remodeling were shown in experimental groups. 2. In histomorphometric analysis, the bone contact ratios were 38.5% for experimental group 1, 29.5% for experimental group 2 and 11.9% for control group. Experimental groups were higher than control group(p<0.05) (Fig. 6, Table IV). The bone area ratios were 60.9% for experimental group 2, 46.4% for experimental group 1 and 36.0% for control group. There was no significantly statistical difference between experimental groups and control group(p<0.05) (Fig. 8, Table VII) 3. In comparision of the bone contact ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group at the 1st thread (p<0.05) and experimental group 1 (1.8mT) was higher than control group at the 3rd thread(p<0.05) (Fig. 7, Table V, VI). 4. In comparision of the bone area ratios at each measurement sites according to magnetic intensity, experimental group 2(5.6mT) was higher than control group and experimental group 1 (4.0mT) at the 1st thread(p<0.1) and experimental group 2(4.4mT) was higher than experimental group 1 (1.8mT) at the 3rd thread(p<0.1) (Fig. 9, Table IX, X). Experiment group 2 was largest, followed by experiment group l and control group at the 3rd thread of implant. There was a significant difference at the 1st thread of control group & experiment group 2, and at 1st thread & 3rd thread of experiment group 1 & 2, and not at control group experiment group 1.(p<0.1)

• Journal of Ginseng Research
• /
• v.13 no.2
• /
• pp.169-173
• /
• 1989

Seven year old ginseng was investigated for yield , the relationship between yield and percent missing plant and red ginseng quality. Yield was 2.06 kg/kan (3.3 m2) and percent missing plant was 27.1%. The highest yield plot showed 3.58 kg/kan and potential yield appeared to be 4.5 kg/kan. Yields of 1st, End and 3rd line showed significant negative linear correlation with percent missing plant. Potential yield without missing plant was in decreasing order of 1>2)3>5) 4 and negatively correlated with unit yield decrease per percent missing plant. Potential yield of 1st line was 6.56 kg/tan. Soft X-ray absorbtion characteristics was not different from that of 6 year old ginseng. Red ginseng grade and percent occurence of red ginseng quality factors were not different from those of 6 years old ginseng. The weight of red ginseng per root was much greater than that of 6 years ginseng. In view of yield and quality of fresh and red ginseng the production of red ginseng from 7 years old ginseng appears to be economically feasible.

• Korean journal of applied entomology
• /
• v.12 no.3
• /
• pp.109-114
• /
• 1973

In order to use the red wood ants (Formica sp.) as a resources of natural enemy of pine caterpillar (Dendrolimus spectabilis Butler), the distribution of red wood ants in Gyeongnam Province, general ecology, and the limit of transplantation was investigated. The results obtained were summarized as follows: 1. Red wood ants preyed upon 1st to 3rd instar of pine caterpillar. 2. Red wood ants were distributed to 474 locations of 18 county, covering 7,702, $559m^2$ in Gyeongnam Province. 3. The distribution of red wood ants was $60\%$ in lower part, $39.5\%$ in middle part and $0.5\%$ in upper part of the mountain. 4. It seems that the height of building nest was directly proportional to the total number of each colony, showing the regression equation of Y=6,200 X-27,813, and the building nest was concerned with soil moisture. 5. It was possible to transplant the red wood ants from May to September, md 5 nests were built by the transplanted ants within one year.

• The Journal of the Korean bone and joint tumor society
• /
• v.5 no.1
• /
• pp.56-62
• /
• 1999

Purpose : This study was conducted to analyze the clinical materials and treatment results of 13 cases of subungual exostosis. Materials and Methods : Thirteen subungual exostoses of the foot treated from January 1991 to December 1997 were studied. We analyzed the clinical data and results of treatment to identify the clinical characteristics of this disease. We investigated the location, shape and relation of exostosis to phalanx with simple x-ray of the foot to identify the radiological characteristics. All the cases were sent to pathologic examination after resection to determine the pathological characteristics. Results : The results of physical examination on presentation were various. Most cases were located at the dorsomedial side of the distal phalanx and were involved in the toe nail. Eleven cases were located at great toes and one each at the 2nd and 3rd toe. Causes of exostosis were not clear, but 2 cases were related to trauma. For the type of exostosis, 7 cases were sessile and 6 were stalk type. On histologic examination, 9 cases showed a cartilaginous portion with overlying proliferating fibrous tissue and underlying bone formation. There was a gradual maturation of spindle cell proliferation from cartilage to cancellous bone. The cartilage was moderately cellular with some pleomorphism, but true anaplasia was not present. Conclusion : The clinical presentation and findings of simple x-rays were most helpful in diagnosing subungual exostosis. Complete excision of the mass achieved complete relief of symptoms and recovery without recurrence in all cases.

• Journal of Korean Society for Atmospheric Environment
• /
• v.3 no.2
• /
• pp.53-61
• /
• 1987

Automatic and manual rain smaplers wre installed at the roof of National Institute of Environmental Research (NIER), and the rain sampling and measurement were conducted during the period April to August 31, 1987. The rain sampling and measurement were carried out in the following manners: The 1st : Acidity and conductivity were measured entirely by automatic rain sampler (continuous measurement) The 2nd : Acidity and conductivity wrer measured in the laboratory with the sample that was taken out of automatic rain sampler. The 3rd : Acidity and conductivity were measured in the laboratory with the sample that was taken out of manual rain sampler. Afterwards, those different measurement values were compared each other and the following conclusions were obtained: 1) The pH of the continous measurement by the automatic sampler was lower than that of the laboratory measurement, and it was reversed in case of the conductivity. 2) The significance was recognized at 5% risk ratio for the population mean of difference of the measurement values of the pH and conductivity from both samples. 3) The significance was not recognized at 5% risk ratio by the analysis of variance by one way layout for the pH and conductivity. 4) The significance was recognized at 5% risk ratio by the analysis of variance by two way layouts for the pH conductivity. 5) The significance was recognized at 5% rrisk ratio for the differences of the pH values obtained by oboth samplers, and no significance was recognized for conductivity. 6) In comparison of the measurement values from the two samplers were shown a good correlation for pH; correlation coefficient (r) = 0.63, and regression equation Y = 0.53X + 2.78. For conductivity, the correlation was also excellent; correlation coefficient (r) = 0.53 and regression equation Y = 0.63X + 5.65.

• Journal of Chest Surgery
• /
• v.23 no.5
• /
• pp.1003-1008
• /
• 1990

Primary choriocarcinoma of the lung is extremely rare and have been reported ten and several cases only in the literature. It is very difficult to confirm the "Pure primary pulmonary choriocarcinoma" clinically, so most cases that have been reported in the literature confirmed by autopsy and the prognosis is relatively poor compared with metastases. We experience one case of the primary pulmonary choriocarcinoma. She was 53 year old multiparous woman[4 \ulcorner0 \ulcorner2 \ulcorner0] who complain right chest pain for 4 years. On plain film and computerized tomogram of the thorax at admission, 2.5cmx3.5cmx5 cm sized, well demarcated ovoid mass was founded on the right middle lobe just below the parietal pleura and growing rapidly on plain film to 5cm x 6.5cm x 7cm after 15 days. We confirm the choriocarcinoma in the lung by percutaneous needle aspiration biopsy and strongly suspect primary after various examination for rule out metastases from the ovary or uterus. We perform middle lobe lobectomy because that can not confirm the primary or the metastases because there are not complete histological examination by bilateral ovariectomy and hysterectomy, and under the belief that extragestational or extragonadal primary choriocarcinoma is more resistant to the chemotherapy, and could be reduce the duration of hospitalization and the amount of chemotherapy used to achieve remission On 14th postoperative day, serum p-HCG level was returned to normal limit, and perform chemotherapy two times on 3rd and 5th week for prevention surgical traumatic hematogenous metastases or undetected microfocus, but the patient expire on 68th postoperative day due to intracerebral hemorrhage in the intracranial choriocarcinoma which strongly suspected surgical traumatic hematogenous metastases.etastases.

• Journal of the Korean Institute of Telematics and Electronics D
• /
• v.36D no.7
• /
• pp.26-33
• /
• 1999

In order to examine the effect of beam location n the performance of bridge type piozoresistive silicon accelerometer, three sensors having different location of beams were simulated by FEN(finite element method) and fabricated by RIE(reactive ion etching) and KOH etching method using SDB(silicon direct bonding) wafer, Results of the FEM simulation present that the 1st resonace frequency and Z axis sensitivity of each sensor are identical but the 2nd, and the 3rd resonace frequency and X, Y axis sensitivity are different. Even though the 1st resonance frequency and Z axis sensitivity measured from fabricated sensors do not perfectly coincide with each other, all 3 type sensors present 180 ~ 220N/G of Z sensitivity at 5 V supply voltage and 1.3 ~ 1.7kHz of the 1st resonance frequency and about 2% of lateral sensitivity.