• Journal of applied mathematics & informatics
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• v.14 no.1_2
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• pp.157-172
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• 2004

An age-dependent branching process where disasters occur as a renewal process leading to annihilation or survival of all the cells, is considered. For such a process, the total mean sojourn time of all the cells in the system is analysed using the regeneration point technique. The mean number of cells which die in time t and its asymptotic behaviour are discussed. When the disasters arrival as a Poisson process and the lifetime of the cells follows exponential distribution, elegant inter- relationships are found among the means of (i) the total number of cells which die in time t (ii) the total sojourn time of all cells in the system upto time t and (iii) the number of living cells at time t. Some of the existing results are deduced as special cases for related processes.

• Journal of Trauma and Injury
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• v.19 no.2
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• pp.113-120
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• 2006

Purpose: The aim of this study was to evaluate the clinical characteristics of classic heat stroke in Korea and to identify factors of prognosis for heat stroke by comparing a survival group with a non-survival group. Methods: We retrospectively analyzed 27 patients with heat stroke who visited the Emergency Department of Kyungpook National University Hospital from March 2001 to February 2005. First, we divided the patients into two groups, the classic heat stroke group and the exertional heat stroke group, and compared them. Second, we compared the survival group with the non-survival group. Age, sex, cause, place where patients were found, underlying diseases, cooling time, performance of endotracheal intubation, initial Glasgow Coma Scale, initial vital sign, and laboratory findings were reviewed. Results: Five of 27 patients in heat stroke died. The classic heat stroke group had 20 patients. They were old and had more patients in the bathroom than the exertional heat stroke group had. The non-survival group showed lower blood pressure, lower initial GCS score, and higher respiratory rate than the survival group. In laboratory findings, the non-survival group also showed lower$HCO_3-$ level, lower albumin level, lower glucose level, more prolonged PT, and higher CK-MB level than the survival group. Delay in recognition of heat stroke and cooling were poor prognostic factors in heat stroke. Conclusion: The classic heat stroke group had patients who were old and found in the bathroom. Early recognition and treatment of heat stroke is important to reduce mortality. Cooling time, initial GCS score, mean arterial pressure, resipratory rate, $HCO_3-$, PT, CK-MB, and albumin seem to be meaningful when forming a prognosis for heat stroke patients.

• Journal of Chest Surgery
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• v.56 no.6
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• pp.403-411
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• 2023

Background: The concept of oligo-recurrence has not been generally applied in esophageal cancer. This study aimed to determine the prognostic significance of the number of recurrences in esophageal cancer. Methods: Patients with squamous cell carcinoma who underwent curative esophagectomy with R0 or R1 resection and who experienced a confirmed recurrence were included. The study included 321 eligible participants from March 2001 to December 2019. The relationship between the number of recurrences and post-recurrence survival was investigated. Results: The mean age was 63.8±8.1 years, and the majority of the participants (97.5%) were men. The median time to recurrence was 10.7 months, and the median survival time after recurrence was 8.8 months. Multiple recurrences with simultaneous local, regional, and distant locations were common (38%). In terms of the number of recurrences, single recurrences were the most common (38.3%) and had the best post-recurrence survival rate (median, 17.1 months; p<0.001). Patients with 2 or 3 recurrences showed equivalent survival to each other and longer survival than those with 4 or more (median, 9.4 months; p<0.001). In the multivariable analysis, the significant predictors of post-recurrence survival were body mass index, minimally invasive esophagectomy, N stage, R0 resection, post-recurrence treatment, and the number of recurrences (p<0.05). Conclusion: After esophagectomy, the number of recurrences was the most significant risk factor influencing post-recurrence survival in patients with esophageal cancer. In esophageal cancer, oligo-recurrence can be defined as a recurrence with three or fewer metastases. More intensive treatment might be recommended if oligo-recurrence occurs.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.2
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• pp.807-812
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• 2014

Background: The clinical course of the neoplasm may vary due to both patient and tumor cell characteristics. Aim: The aim of this study was to research the influence of certain clinical and pathological features on the prognosis of early stage breast cancer. Materials and Methods: This study included 117 women that were treated and followed-up in between the years 2001-2011. The demographic, clinical and histopathological features of the cases were reviewed retrospectively. Statistical analysis: In categorical comparisons between groups, cross-tab statistics were provided and significance levels were estimated using chi-square test. Cox regression analysis, Pearson and Spearman correlation tests, and the Kaplan-Meier test were also used. Results: With an average of 35-months follow-up, the mean disease-free survival of patients was 91 months and the mean overall survival time was 132 months. In the whole study group, the disease-free survival rates were 88, 84, 83 and 52%, while the overall survival rates 95, 94, 83, and 83% within the first, third, fifth and tenth years, respectively. The disease-free and overall survival rates were decreased with increasing tumor grades, though this was not statistically significant. The presence of lymphovascular invasion, positive staining with Ki67 and postmenopausal status were associated with shorter disease-free and overall survival times. In multivariate analysis, only age and Her2/neu receptor status influenced the prognosis significantly. Conclusions: In parallel to clinical, histopathological, and immunohistochemical prognostic features in breast cancer, in this study positive Her2/neu receptor status, a previously accepted poor prognostic factor, was found to have positive influence after trastuzumab treatment.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.49 no.1
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• pp.13-20
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• 2023

Objectives: Ultra-wide implants may be used as a replacement if existing implants fail. This study was conducted to evaluate the factors influencing the prognosis and failure of ultra-wide implants. Patients and Methods: This study evaluated whether sex, age, site, diameter, length, additional surgery, implant stability (primary and secondary), and reason for ultra-wide implant placement affect the 5-year survival and success rates and marginal bone loss (MBL) of ultra-wide implants. Seventy-eight ultra-wide implants that were placed in 71 patients (39 males and 32 females) from 2008 to 2010 were studied. One-way ANOVA analysis was conducted to evaluate the statistical significance of MBL according to the patient's sex, implant site, and diameter. Independent sample t-tests were used to determine the statistical significance of MBL analysis which was used to determine the significance of the 5-year success and survival rates related to the variables. One-way ANOVA was conducted to evaluate the statistical significance of sex, implantation site, diameter, and MBL. Independent sample t-tests were used to evaluate the correlation between implantability and MBL for implantation reasons, while additional surgery, length, and Kaplan-Meier analysis were used to evaluate 5-year survival and success rates. Results: The mean age of patients was 54.2 years with a survival rate of 92.3% and a success rate of 83.3% over a mean 97.8-month period of observation. MBL averaged 0.2 mm after one year of prosthetic function loading and 0.54 mm at the time of final observation. Success rates correlated with primary stability (P=0.045), survival rates correlated with secondary stability (P=0.036), and MBL did not correlate with any variables. Conclusion: Ultra-wide implants can be used to achieve secure initial fixation in the maxillary and mandibular molar regions with poor bone quality or for alternative purposes in cases of previous implant failure.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.9
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• pp.3697-3701
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• 2015

Background: Cholangiocarcinoma (CHCA) is serious public health problem in Thailand, especially in the northeastern and northern regions. CHCA is known as one of the most aggressive malignant tumors associated with local invasion and a high rate of metastasis. A crucial step in the invasion process is the proteolytic degradation of the extracellular matrix (ECM) and basal membranes, for which several studies have shown a critical role played by matrix metalloproteinase-11 (MMP-11). Objective: This study aim to detect MMP-11 expression in CHCA specimens and any correlation with survival time. Materials and Methods: A retrospective analysis was conducted of 30 patients with CHCA in Rajvithi hospital, who had undergone immunohistochemical staining of MMP-11. Relationships between clinicopathological data and MMP-11 expression in CHCA specimens were analyzed by the ${\chi}^2$ test or Fisher's exact test. The estimated survival and the survival differences were analyzed by the Kaplan-Meier method and the log-rank test, respectively. Results: MMP-11 expression was found in 15 specimens (50%). The overall mean survival time is 237.0 days (95% CI 135.4-338.5, SD 271.9). Specimens with a positive MMP-11 had an average survival time of 136.7 days (95%CI 50.3-223.1, SD 156.0). Survival differences was signficant for the positive and negative MMP-11(p=0.022), but not well differentiated tumor and moderate to poor differentiated tumor (p=0.755), CA19-9 level of >1,000 and <1,000 (p=0.488), and between advanced and non-advanced staging (p=0.388). Conclusions: The positive MMP-11 expression indicates poor prognosis in CHCA specimens.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.24
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• pp.10837-10840
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• 2015

To assess survival outcomes in a retrospective study, recurrent epithelial ovarian cancer patients were divided into three groups according to the platinum free interval as follows: platinum refractory that included the patients with tumor progression during treatment; platinum resistant and platinum sensitive that included the patients with tumor progression less than or more than six months, respectively. Clinical data for tumor progression in epithelial ovarian cancer patients treated at Chiang Mai University Hospital between January, 2006 and December, 2010 were reviewed. Thirty-nine patients were in the platinum refractory group while 27 were in the platinum resistant group and 75 in the platinum sensitive group. The mean age, the parity, the administration of neoadjuvant chemotherapy and the serous type did not significantly different across groups while the mean total number of chemotherapy regimens, the early stage patients, the patients with complete surgery and the surviving patients were significant more frequent in the platinum sensitive group. Regarding subsequent treatment after tumor recurrence, 87.2% underwent chemotherapy. With the median follow up time at 29 months, the median overall survival rates were 20 months, 14 months and 42 months in platinum refractory, platinum resistant and platinum sensitive groups, respectively (p<0.001). In addition, when the platinum sensitive patients developed the next episode of tumor progression, the median progression free interval time was only three to four months. In conclusion, the outcomes for platinum refractory the and platinum resistant groups was poorer than the platinum sensitive group. However, subsequent progression in the platinum sensitive group was also associated with a poor outcome.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.1
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• pp.25-28
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• 2014

Background: This study analyzed whether socio-economic factors affect the cause specific survival of soft tissue sarcoma (STS). Methods: Surveillance, Epidemiology and End Results (SEER) soft tissue sarcoma (STS) data were used to identify potential socio-economic disparities in outcome. Time to cause specific death was computed with Kaplan-Meier analysis. Kolmogorov-Smirnov tests and Cox proportional hazard analysis were used for univariate and multivariate tests, respectively. The areas under the receiver operating curve were computed for predictors for comparison. Results: There were 42,016 patients diagnosed STS from 1973 to 2009. The mean follow up time (S.D.) was 66.6 (81.3) months. Stage, site, grade were significant predictors by univariate tests. Race and rural-urban residence were also important predictors of outcome. These five factors were all statistically significant with Cox analysis. Rural and African-American patients had a 3-4% disadvantage in cause specific survival. Conclusions: Socio-economic factors influence cause specific survival of soft tissue sarcoma. Ensuring access to cancer care may eliminate the outcome disparities.

• Journal of Chest Surgery
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• v.28 no.3
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• pp.287-292
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• 1995

From March 1989 to June 1994, 24 casesof esophageal cancer were treated surgically. Among 24, male was 22 cases, female was 2 cases, and the age ranged from 46 to 75, the mean was 59.8. Symptoms were dysphagia[86.9% , weight loss[65.2% and retrosternal pain or discomfort[47.8% . The tumor was located cervical esophagus in two, upper esophagus in three, middle esophagus in 12 and lower esophagus in 7. Among 24 patients, 22 were curative resection, partial esophagectomy with esophagogastrostomy[18 cases or colon interposition [3 cases , with total esophagectomy with musculocutaneous flap[1 case , with feeding jejunostomy or gastrostomy in two cases.Postoperative complications revealed 10 patients[45.4% , as followed ; pleural effusion and pneumonia in 5, passage disturbance in 4, empyema and wound infection in 3, esophagopleural fistula and sepsis in 2, anastomotic site leakage and respiratory failure in each 1. The operative mortality was 13.6 % [3/22 and causes of death were respiratory failure in 1 case and sepsis in 2 cases.During follow-up work, 8 cases died during follow-up period, mean survival time was 15.2 months in curative resection group. One year survival rate was 55.3% in resected group. Also, cancer recurrence revealed in 1 cases.

• The Journal of the Korean dental association
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• v.47 no.4
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• pp.184-190
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• 2009

OBJECTIVE The purpose of clinical study was to evaluate the survival of dental implants used in restoring patients with implant supported removable partial dentures (ISRPDs) of different configurations. MATERIALS AND METHODS The sample consisted of 20 consecutively treated partially edentulous patients, who, between 2003 and 2008, had a total of 84implants placed in different arch sites and who were treated with ISRPDs. The mean age was 57 years. Mean follow up time from delivery of ISRPDs was 3 years 2 months (range, 1 to 6 years). Osseointegration failure, postoperative complication of dental prosthesis, and the success rate of ISRPDs were retrospectively evaluated using clinical and radiographic examination. RESULT The overall implant survival rate was 100%. During follow up, the one clasp of removable partial denture was broken in 1 year11 months after prosthesis delivery. All patients were satisfied with their prosthesis. CONCLUSIONS Implant supported removable partial dentures could serve as favorable prognosis. Careful patient selection, with an appropriate maintenance and recall system, is recommended to obtain satisfactory results.