• Bulletin of the Korean Mathematical Society
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• v.47 no.2
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• pp.287-293
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• 2010

It is well known that there is a residual subset J of the space of $C^1$-diffeomorphisms on a compact Riemannian manifold M such that the maps f $\mapsto$ chain recurrent set of f and f $\mapsto$ number of chain components of f are continuous on J. In this paper we get the flow version of the above results on diffeomorphisms.

• Kyungpook Mathematical Journal
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• v.54 no.2
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• pp.165-171
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• 2014

Let M be a manifold with a volume form ${\omega}$ and $f:M{\rightarrow}M$ be a diffeomorphism of class 𝒞$^1$ that preserves ${\omega}$. We prove that if M is almost bounded for the diffeomorphism f, then M is chain recurrent. Moreover, we get that Lagrange stable volume-preserving manifolds are also chain recurrent.

• Journal of Chest Surgery
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• v.8 no.1
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• pp.9-12
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• 1975

Four patients with postpneumonectomy empyema were treated successfully by modification of Clagett`procedure. Their primary diseases were chronic bronchiectasis, empyema with bronchopleural fisula, pulmonary tuberculosis, and pyohemothorax. The time interval between 1st and 2nd operation was 26.5 months in average. The pleural space was irrigated with various kinds of antiseptic solutions for 23.3 days in average and debrided, filled with antibiotic saline solution. After the procedure, patients had no recurrences of empyema and discharged from hospital after brief days. (averages: 15.5 days)

• Bulletin of the Korean Mathematical Society
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• v.58 no.2
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• pp.315-326
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• 2021

Korobov type polynomials are introduced and extensively investigated many mathematicians ([1, 8-10, 12-14]). In this work, we define unified Apostol Korobov type polynomials and give some recurrences relations for these polynomials. Further, we consider the q-poly Korobov polynomials and the q-poly-Korobov type Changhee polynomials. We give some explicit relations and identities above mentioned functions.

• Archives of Plastic Surgery
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• v.34 no.5
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• pp.574-579
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• 2007

Purpose: The number of sore patients are increasing steadily, especially in old ages, chronic disease and paralytic patients. Most of patients need to surgical treatment. The aim of this paper is to assess clinical analysis of surgical treatment and to consider operative methods, complications, and recurrences.Methods: We reviewed the data from 82 consecutive patients with 101 pressure sores from March 2003 to May 2006 to discuss the occurrence rate and recurrence rate according to the site on the basis of the presence or absence of paraplegic and its etiology-the patients were categorized into three diagnostic groups: traumatic paraplegics(TP), nontraumatic paraplegics (NTP), and nontraumatic nonparaplegics(NTNP). We examined the sites and sizes of each lesions, patient's state, primary causes of pressure sore, operative methods as each sites and groups, occurrence of complications and recurrences on each groups. Results: In 82 patients, 52 patients were male, 30 patients were female. The male to female ratio was 1.7 :1. Mean age was 55.8 years. 27 patients were in TP group, 35 in NTP group, and 20 in NTNP group, respectively. The common site of sore were sacral area (50.5%), greater trochanteric area(15.8%) and ischial area(13.9%). In each group, incidence rate of recurrence and complication were 11.1%, 40.7% in TP, 5.7%, 5.7% in NTP and 15%, 45% in NTNP. Conclusion: Surgeons must consider the general condition of the patient and possibility of recurrence and returning of daily life. We propose that cutaneous flap, fasciocutaneous flap or skin graft as well as musculocutaneous flap be useful to repair of sore site as each patient's state.

• Archives of Plastic Surgery
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• v.38 no.6
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• pp.815-820
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• 2011

Purpose: Perforator flaps have been widely used for reconstruction of pressure sores because they have many benefits, especially reducing tension. Otherwise in order to prevent recurrence of a pressure sore, sufficient thickness of a flap is desirable, so a musculocutaneous flap is also useful for reconstruction of a pressure sore. Therefore, the authors considered about the postoperative results of reconstruction of pressure sores between using perforator flaps and musculocutaneous flaps. Methods: In this study, 33 patients (46 flaps) who underwent reconstructive operation of pressure sores from January 2007 to February 2011 were reviewed. Patients operated by using perforator flaps were 18 (18 flaps), and musculocutaneous flaps were 17 (28 flaps). We studied postoperative complications and recurrence. Results: We experienced five patients (10 flaps) with complications or recurrences who were operated using musculocutaneous flaps and one patient using a perforator flap. One case using a perforator flap stemmed from dehiscence caused by a urinary fistula occurring in two months after the surgery. Among ten cases using musculocutaneous flaps, one case was caused by total necrosis of flap, five cases by partial necrosis of flap and dehiscence, and four cases by recurrences during follow-up period. Conclusion: Even if more cases were required, it can be more considerable to operate using the perforator flap rather than the musculocutaneous flap to reduce the complication or recurrence of pressure sore.

• The Journal of the Korean bone and joint tumor society
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• v.11 no.1
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• pp.88-93
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• 2005

Malignant transformation of a solitary osteochondroma is rare, and usually takes form of a chondrosarcoma. We present a case of low grade osteosarcoma arising in a solitary osteochondroma of the right femur in a 30-year-old woman. As the lesion was initially continuous with corresponding components of the parent bone, so the possibilities of other diagnoses were excluded. After the initial excision, there were 3 times of recurrences during the follow up period of 3 years. The histologic subtypes of the recurred osteosarcomas were different each other, which were high grade chondroblastic, osteoblastic and fibroblastic respectively.

• Advances in pediatric surgery
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• v.17 no.1
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• pp.35-44
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• 2011

Thyroglossal duct cysts (TGDC) are the most common type of congenital developmental anomaly encountered in the anterior midline of the neck in childhood. The aim of the study was to evaluate the clinical characteristics of TGDC and identify any factors that could be related to recurrence after surgery. This study consisted of a retrospective chart review of 45 patients treated at Kyungpook National University Hospital for TGDC between 1990 and 2008. All records were reviewed for age and sex, length of history, presentation, diagnostic methods, sizes and locations of cyst, surgical management, histopathology of the lesion and recurrences. The statistical analysis of risk factors for recurrence was made using the Fisher's exact test with a significance level of p (0.05. The male to female ratio was 2.2:1 with a male preponderance. The mean age at operation was 5 years and 2 months (4 months - 17 years). The most common presenting symptom was a nontender cervical mass (78 %). Most TGDC were found in the midline position. Twenty four were infrahyold, 17 were hyoid, and 4 were suprahyoid level. Forty one (91 %) patients received the Sistrunk operation, and 4(9 %) patients received Cyst excision. Postoperative a seroma developed in six patients in the early postoperative days. There were a total of 3(6.6 %) recurrences, 2 in patients who had excision only and in one patient who had the Sistrunk operation. Univariate analysis for risk factors with recurrence showed that there was no statistical relationship between the presence of preoperative infection and the development of recurrence. The removal of hyoid bone along with TGDC was a statistically significant risk factor for recurrent disease. This study suggests that the Sistrunk operation Is the treatment of choice for TGDC in order to reduce recurrence.

• Archives of Plastic Surgery
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• v.36 no.4
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• pp.417-421
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• 2009

Purpose: Dermatofibrosarcoma protuberans(DFSP) is a moderate - degree malignant tumor of soft tissue from dermis to fat layer with high recurrences(11% to 73%) due to its local infiltrative characteristic. Many debates and controversies in deciding accurate surgical margin were presented before, but references about depth of invasion and appropriate surgical excision level were not properly made out. Therefore, we tried to identify the degree of tissue invasion of DFSP. Methods: Twenty patients, including 8 patients with recurrent lesions, over last 10 years were reviewed retrospectively. Different surgical margins were applied according to the location and based on histopathologic result, we have defined as a 'deep tissue invasion' if there were infiltration of tumor cell into fascia or underlying muscle layer was present. All invaded tissue including dermis, fat, fascia and muscle were excised until no tumor cell was found during intraoperative frozen section biopsy. And comparative analysis of deep tissue invasion according to age, primary site, duration of disease and recurrence was done. Results: Thirteen patients(65%) showed deep tissue invasion and incidence was found to be increasing with age(over 30 years old). All patients with DFSP on head and neck region revealed deep tissue invasion followed by trunk(54%) and lower extremities(50%). There was no relationship between duration of disease and deep tissue invasion. Conclusions: It is clear that many cases of DFSP had a deep tissue invasion. And high prevalence of deep tissue invasion with age, primary site was intimately associated. So, underlying deep tissue must be completely examined and excised sufficiently throughout the operation for clear resection of DFSP with no recurrences, especially when age is over 30s and on head and neck region.

• The Korean Journal of Nuclear Medicine Technology
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• v.18 no.1
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• pp.145-148
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• 2014

Purpose: Serum thyroglobulin (Tg) determination has been reported to be a sensitive indicator of persistent or recurrent differentiated thyroid cancer (DTC) after total thyroidetectomy. In patients free of metastasese and recurrences after a complete thyroidectomy and radioiodine removal for DTC, the Tg is usually <1 ng/mL or can no longer be detected even with TSH stimulation. Therefore, report in low Tg levels and selecting criteria for retest is very important. The purpose of this study was to establish selecting criteria for retest which is efficient at reliability improvement and Turn around time (TAT). Materials and Methods: Sera from 137 patients with DTC were divided into two groups as first(<1.0 ng/mL or >4.0 ng/mL) and second(1.0-4.0 ng/mL). In case of group(<1.0 ng/mL) is in patient free of metastases and recurrences, >4.0 ng/ml is low coefficient of variation (CV%) at internal quality control and good linearity at standard curve. Therefore first group began with Delta/Panic check (D/P) and second group surveyed with the latest results. In that the latest results were <1.0 ng/ml, we checked the thyroxin withdrawal. Finally selected specimen retested with raw specimen. Results: In first group, we was able to reduce the retest rate(30.8% to 7.7%). and In second group, 40% to 5%. The total retest rate was 7.3%. Conclusion: If using the selecting criteria for retest, is helpful to accuracy and quickness of the result report.