• Journal of the Korean Society for Precision Engineering
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• v.15 no.1
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• pp.117-129
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• 1998

Micro-hole drilling (holes less than 0.5 mm in diameter with aspect ratio larger than 10) is recently having more attention in a wide spectrum of precision production industries. Alternative methods such as EDM. laser drilling, etc. can sometimes replace the mechanical micro-hole drilling but are not acceptable in PCB manufacture because of the inferior hole quality and accuracy. The major difficulties in micro-hole drilling are related to small signal to noise ratios, wandering motions of the inlet stage, high aspect ratios, high temperatures and so forth. Of all the difficulties. the most undesirable one is the increase of drilling force as the drill proceeds deeper into the hole. This is caused mainly from the chip effects. Peck-drilling is thus widely used for deep hole drilling despite that it suffers from low productivity. In the paper, a method of cutting force regulation is proposed to achieve continuous drilling. A PD and a sliding mode control algorithms were implemented through controlling the spindle rotating frequency. Experimental results show that the sliding mode control reduces the nominal cutting force and the variation of the cutting force better than the PD control. The advantages of the regulation, such as increase of drill life, fast stabilization of a wandering motion, and the precise positioning of the hole are verified in experiment.

• Clinical and Experimental Pediatrics
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• v.59 no.5
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• pp.242-245
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• 2016

Thromboembolic complications (TECs) are clinically important sequelae of nephrotic syndrome (NS). The incidence of TECs in children is approximately 2%-5%. The veins are the most commonly affected sites, particularly the deep veins in the legs, the inferior vena cava, the superior vena cava, and the renal veins. Arterial thrombosis, which is less common, typically occurs in the cerebral, pulmonary, and femoral arteries, and is associated with the use of steroids and diuretics. Popliteal artery thrombosis in children has been described in cases of traumatic dissection, osteochondroma, Mycoplasma pneumoniae infection, and fibromuscular dysplasia. We report of a 33-month-old girl with bilateral iliac and popliteal arterial thrombosis associated with steroid-resistant NS due to focal segmental glomerulosclerosis. Her treatment involved thrombectomy and intravenous heparinization, followed by oral warfarin for 8 months. Herein, we report a rare case of spontaneous iliac and popliteal arterial thrombosis in a young child with NS.

• Journal of Oral Medicine and Pain
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• v.17 no.2
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• pp.19-25
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• 1992

The pressure pain thresholds of head and neck muscles of patients suffering from tensiontype headache220, all female, ages ranged from 13 to 50 years (28.4$\pm$9.6) and 39 healthy controls, all female, ages ranged from 14 to 46 years (24.4$\pm$9.2) were recorded by the electronic algometer (Electyronic Algometer Type I, Somedic, Stockholm, Sweden). And the obtained results were as follows : 1. The pressure pain thresholds of patient group were lower than those of controls in superior sternocleidomastoid muscle, middle sternocleidomastoid muscle, and trapezius insertion muscle (P<0.001) 2. The pressure pain thresholds of patient group were not different from those of controls in anterior temporal, middle temporal, posterior temporal, deep masseter, anterior masseter, inferior masseter, medial pterygoid, posterior digastric, splenius capitus and upper trapezius muscle (P>0.05). 3. Seventy-one percent of tension-type headache patients had more than one muscle, of whicb pressure pain threshold was lowered significantly (less than mean of control - 1.5SD). 4. The pressure pain thresholds of head and neck muscles should be considered as a criterion for the diagnosis of tension-type headache.

• Clinics in Shoulder and Elbow
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• v.8 no.2
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• pp.154-157
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• 2005

Elastofibroma dorsi is a benign soft tissue mass, not well-known because of its low incidence, and usually located between the chest wall and the inferomedial aspect of the scapula. This lesion is not true neoplasm but rather reactive hyperplasia of elastic fibers. It is mostly nontender mass, but occasionally causes snapping symptom. This tumor should be considered as a differential diagnosis of snapping scapula. The clinical diagnosis is made by magnetic resonance imaging and confirmed by pathologic findings. We present a case report of a female with elastofibroma dorsi, who had that the chief complaint was snapping scapula and palpable mass. We emphasize that snapping lesions located deep beneath the inferior tip of the scapula on the chest wall should arouse suspicion of an elastofibroma dorsi.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.39 no.6
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• pp.289-291
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• 2013

Moyamoya disease is a rare neurovascular disorder that involves constriction of certain arteries in the brain. In patients with moyamoya disease, it is very important to prevent cerebral ischemic attacks and intracerebral bleeding caused by fluctuating blood pressure and increased respiration. A 40-year-old woman with moyamoya disease was scheduled for extraction of her right upper and lower impacted wisdom teeth. Her lower impacted wisdom tooth was situated close to the inferior alveolar nerve. We decided to continue her oral antiplatelet therapy and planned intravenous sedation with analgesic agents administered approximately five minutes prior to extraction of the root of the mandibular wisdom tooth. Oral analgesic medications were regularly administered postoperatively to alleviate pain and anxiety. During the perioperative period, no cerebrovascular event occurred, and the wisdom teeth were successfully extracted as per the planned procedure. It is thought that the perioperative risks of wisdom tooth extraction in patients with moyamoya disease can be minimized with the use of our protocols.

• Journal of Yeungnam Medical Science
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• v.23 no.1
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• pp.1-9
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• 2006

Breast reconstruction provides dramatic improvement for patients with severe deformity. The reconstruction not only restores aesthetically acceptable breast for patients with mastectomy deformity but also recovers psychological trauma of 'losing feminity' after the cancer mastectomy. There are many options for breast reconstruction from simple prosthetic insertion to a flap operation using autologous abdominal tissue. The choice of operation method depends on the physical condition of the patient, smoking habits, and economic status. Among the many options, the method that uses the lower abdominal tissue is known as the TRAM (transverse rectus abdonimis myocutaneous) flap. Since the introduction of the TRAM flap in 1982 by Hartrampf, the art of breast reconstruction using lower abdominal tissue has been progressively refined to pedicle flap, muscle-sparinga TRAM flap, and recently there have been exciting and revolutionary changes associated with the adoption of the concept of perforator flap. This refined method of breast reconstruction utilizes lower abdominal tissue nourished by the deep inferior epigastric perforator (DIEP). With the DIEP free flap, almost all of the rectus muscle and anterior rectus sheath are preserved and the donor morbidity is minimized. Different from previous flap methods using lower abdominal tissue, DIEP free flap method preserves function of the rectus muscle completely. 1) Understanding the entire progression of breast reconstruction methods using lower abdominal tissue is necessary for plastic surgeons; the understanding of each step of the exciting progression and the review of the past history of the TRAM flap may provide insight for future development.

• Archives of Plastic Surgery
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• v.50 no.2
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• pp.153-155
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• 2023

The vascular anatomy of the deep inferior epigastric artery perforator (DIEP) flap has been well studied in the planning for autologous breast reconstruction. Preoperative imaging with computed tomography angiography (CTA) provides accurate assessment of this vascular anatomy, which varies widely across patients. Several papers to date have described their encounter with an anomalous "epiperitoneal" or "peritoneo-cutaneous" perforator during flap harvest, a perforator that pierces the posterior rectus sheath from a peritoneal origin, to traverse rectus abdominis and supply the DIEP flap integument. In the course of over 3,000 CTA assessments of the vascular anatomy of the abdominal wall, we have encountered dominant peritoneo-cutaneous perforators in 1% of cases, and smaller perforators seen in many more cases, approaching 5% of cases. With increasing sensitivity of imaging, we also describe a unique case of multiple large bilateral peritoneo-cutaneous perforators, and present these findings in the context of DIEP flap harvest. It is critical to recognize these peritoneo-cutaneous perforators preoperatively to avoid mistaking them for a DIEP during the raising of a DIEP flap. The routine use of preoperative CTA enables the safe identification of individual vascular anatomy, including significant peritoneo-cutaneous perforators.

• Journal of Korean Traditional Oncology
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• v.28 no.1
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• pp.25-31
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• 2023

Objectives: With antibiotic resistance one of the biggest threats to global health, we report a case of surgical site infection (SSI) after breast cancer surgery that improved only with the treatment of Taglisodog-eum (托裏消毒飮), Korean herbal medicine, without the use of antibiotics. Methods: The patient diagnosed with ductal carcinoma in situ of left breast underwent nipple areola skin sparing mastectomy and reconstruction using deep inferior epigastric perforator flap. About a month later, superficial SSI occurred at the incision site of breast cancer surgery with general weakness, and Taglisodog-eum treatment was started. To evaluate the effectiveness of the treatment, we compared the infection site conditions before and after treatment. Results: About three weeks after taking Taglisodog-eum, the SSI improved along with the improvement of general weakness. Conclusions: This study shows that Taglisodog-eum may be effective for SSI after breast cancer surgery, and the potential for alternatives to reduce antibiotic use and antibiotic resistance.

• Journal of Chest Surgery
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• v.42 no.6
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• pp.757-762
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• 2009

Background: Compression of the left common iliac vein by the overriding common iliac artery is frequently combined with acute deep vein thrombosis in patients with May-Thurner Syndrome. We evaluate the results of treatment with thrombolysis and thrombectomy followed by stenting in 34 patients with May-Thurner Syndrome combined with lower extremity deep venous thrombosis. Material and Method: The authors retrospectively reviewed the records of 34 patients (mean age: $65{\pm}14$ year old) who had undergone stent insertion for acute deep vein thrombosis that was caused by May-Thurner syndrome. After thrombectomy and thrombolysis, insertion of a wall stent and balloon angioplasty were performed to relieve the compression of the left common iliac vein. Urokinase at a rate of 80,000 to 120,000 U/hour was infused into the thrombosed vein via a multi-side hole thrombolysis catheter. A retrieval inferior vena cava (IVC) filter was placed to protect against pulmonary embolism in 30 patients (88%). Oral anticoagulation with warfarin was maintained for 3 months, and follow-up Multi Detector Computerized Tomography (MDCT) angiography was done at the date of the patients' hospital discharge and at the 6 months follow-up. Result: The symptoms of deep venous thrombosis disappeared in two patients (4%), and there was clinical improvement within 48 hours in twenty eight patients (82%), but there was no improvement in four patients (8%). The MDCT angiography at discharge showed no thrombus in 9 patients (26%) and partial thrombus in 21 (62%), whereas the follow-up MDCT at $6.4{\pm}5.5$ months (32 patients) revealed no thrombus in 23 patients (72%), and partial thrombus in 9 patients (26%). Two patients (6%) had recurrence of DVT, so they underwent retreatment. Conclusion: Stent insertion with catheter-directed thrombolysis and thrombectomy is an effective treatment for May-Thurner syndrome combined with acute deep vein thrombosis in the lower extremity.

• Journal of the Korean Society of Food Science and Nutrition
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• v.18 no.3
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• pp.247-254
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• 1989

In deep-fat frying, the fats and oils are used over and over again, and moisture and air are mixed in to the hot oil. Many reports related to these fats and oils have been established that thermal and oxidative decomposition products and polymers formed under the conditions of deep fat frying are harmful to health. This work was carried out with 3 domestic frying oils and 6 used oils commercially, and that there were difficulties in finding a good definition between fresh oil and used oil with adding unheated oil. As starting materials, commercially used soybean oil and rapeseed oil already passed over induction period in the lipids oxidation standard. From the qualitative point of view, they were inferior to domestic frying oils. Free fatty acid and peroxide value of heated oils were increased gradually by the time pass whereas iodine value were decreased. After adding unheated oil to the heated oil, these values were restored to that of initial levels. On the other hand, content of polar components in the heated oil were directly related to the heating time. This result showed that polar compounds may be a clear indicator of used oils. Fatty acid composition in the used oils, unsaturated fatty acids such as linoleic and linolenic acid decreased while saturated fatty acid content increased with heating.