• Radiation Oncology Journal
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• v.20 no.2
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• pp.155-164
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• 2002

Purpose : A ginkgo biloba extract (GBE) has been known as a hypoxic cell radiosensitizer. Its mechanisms of action are increase of the red blood cell deformability, decrease the blood viscosity, and decrease the hypoxic cell fraction in the tumor. The aims of this study were to estimate the effect of GBE on fractionated radiotherapy and to clarify the mechanism of action of the GBE by estimating the blood flow in tumor and normal muscle. Materials and Methods : Fibrosarcoma (FSall) growing in a C3H mouse leg muscle was used as the tumor model. When the tumor size reached 7 mm in diameter, the GBE was given intraperitoneally at 1 and 25 hours prior to irradiation. The tumor growth delay was measured according to the various doses of radiation (3, 6, 9, 12 Gy and 15 Gy) and to the fractionation (single and fractionated irradiation) with and without the GBE injection. The radiation dose to the tumor the response relationships and the enhancement ratio of the GBE were measured. In addition, the blood flow of a normal muscle and a tumor was compared by laser Doppler flowmetry according to the GBE treatment. Results : When the GBE was used with single fraction irradiation with doses ranging from 3 to 12 Gy, GBE increased the tumor growth delay significantly (p<0.05) and the enhancement ratio of the GBE was 1.16. In fractionated irradiation with 3 Gy per day, the relationships between the radiation dose (D) and the tumor growth delay (TGD) were TGD $(days)=0.26{\times}D$ (Gy)+0.13 in the radiation alone group, and the TGD $(days)=0.30{\times}D$ (Gy)+0.13 in the radiation with GBE group. As a result, the enhancement ratio was 1.19 ($95\%$ confidence interval; $1.13\~1.27$). Laser Doppler flowmetry was used to measure the blood flow. The mean blood flow was higher in the muscle (7.78 mL/100 g/min in tumor and the 10.15 mL/100 g/min in muscle, p=0.005) and the low blood flow fraction (less than 2 mL/100 g/min) was higher in the tumor $(0.5\%\;vs.\;5.2\%,\;p=0.005)$. The blood flow was not changed with the GBE in normal muscle, but was increased by $23.5\%$ ( p=0.0004) in the tumor. Conclusion : Based on these results, it can be concluded that the GBE enhanced the radiation effect significantly when used with fractionated radiotherapy as well as with single fraction irradiation. Furthermore, the GBE increased the blood flow of the tumor selectively.

• Radiation Oncology Journal
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• v.14 no.1
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• pp.1-8
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• 1996

Purpose: We tried to evaluate the role of conventional radiotherapy alone or with neoadjuvant chemotherapy in oropharyngeal cancer in terms of survival rates and to identify prognostic factors affecting survival by retrospective analysis. Materials and Methods: Forty seven patients of oropharyngeal cancer were treated by conventional radiotherapy in our hospital from Nov. 1985 to APr. 1993. Of these, twenty six patients were treated by conventional radio-therapy alone, and 21 patients with neoadjuvant chemotherapy of mostly two or more cycles of cisplatin and pepleomycin. The Patient characteristics of radiotherapy alone group and neoadjuvant chemotherapy group were not different generally. Radiotherapy was performed by 6MV-LINAC and the total radiation doses of Primary tumors were 54.0-79.2 Gy and cervical lymph nodes were 55.8-90.0 Gy with a fraction size of 1.8 or 2.0 Gy per day. The range of follow-up periods was 3-102 months and median was 20 months. The range of a9e was 33-79 years old and median was 58 years old. Results : Overall 3-year actuarial survival rate (3YSR) of all patients was $39\%$. The 3YSRS of stage I (n=5), II (n=11), III (n=12) and IV (n=19) were 60, 55, 33 and $32\%$, respectively The 3YSRS of Tl+2, T3+4 and No, N+ were 55, $18\%$ (p=0.005) and 43, $36\%$ (p>0.1), respectively. There was no difference in 3YSRS between radiotherapy alone group and neoadjuvant chemotherapy group (38 vs $43\%$, p>0.1). According to the original site of primary tumor, the 3YSRS of tonsil (n=32), base of tongue (n=8), soft palate or uvula (n=6) and pharyngeal wall (n=1) were 36 38, 67 and $0\%$, respectively The Patients of soft palate or uvular cancer had longer survival than other primaries but the difference was not significant statistically (p>0.1). Of 32 patients of tonsillar cancer, 22 Patients who had primary extension to adjacent tissue showed inferior survival rate to the ones who had not Primary extension, but the difference was marginally significant statistically (24 vs $60\%$, p=0.08). On Cox multivariate analysis in entire patients with variables of age, T stage, N stage, total duration of radiotherapy, the site of primary tumor and the use of neoadjuvant chemotherapy, only T stage was a significant Prognostic factor affecting 3YSR. Conclusion : The difference of 3YASRS of conventional radiotherapy alone group and neoadjuvant chemotherapy group was not significant statistically. These treatments could be effective in oropharyngeal cancer of early stage, especially such as soft palate, uvular or tonsillar cancer which did not extend to adjacent tissue. But in order to improve the survival of patients of most advanced oropharyngeal cancer, other altered fractionated radiotherapy such as hyperfractionation rather than conventional fractionation or multi-modal approach combining radiotherapy and accessible surgery or concurrent chemotherapy might be beneficial.

• Radiation Oncology Journal
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• v.18 no.1
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• pp.32-39
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• 2000

Purpose :The incidence of adenocarcinoma of the uterine cervix is low. Traditionally, Low Dose Rate (LDR) brachytherapy has been used as a standard modality in the treatment for patients with carcinoma of the uterine cervix. The purpose of this report is to evaluate the effects of the High dose rate (HDR) brachytherapy in the patients with adenocarcinoma of the uterine cervix compared with the LDR. : From January 1971 to December 1992, 106 patients of adenocarcinoma of uterine cervix were treated with radiation therapy in the Department of Radiation Oncology, Yonsei University with curative intent. LDR brachytherapy was carried out on 35 patients and 71 patients were treated with HDR brachytherapy. In LDR Group, 8 patients were in stage I, 18 in stage II and 9 in stage III. External radiation therapy was delivered with 10 MV X-ray, daily 2 Gy fractionation, total dose 40$\~$46Gy (median 48 Gy). And LDR Radium intracavitary irradiation was peformed with Henschke applicator, 22$\~$59 Gy to point A (median 43 Gy). In HDR Group, there were 16 patients in stage 1, 38 in stage II and 17 in stage III. The total dose of external radiation was 40$\~$61 Gy(median 45 Gy), daily 1.8$\~$2.0 Gy. HDR Co-60 intracavitary irradiation was peformed with RALS (Remote Afterloading System), 30 $\~$ 57 Gy(median 39 Gy) to point A, 3 times a week, 3 Gy per fraction. Conclusion : The 5-year overall survival rate in LDR Group was 72.9$\%$, 61.9$\%$, 45.0$\%$ in stage I, II, III, respectively and corresponding figures for HDR were 87.1$\%$, 58.3$\%$, 41.2$\%$, respectively (p>0.05). There was no statistical difference in terms of the 5-year overall survival rate between HDR Group and LDR Group in adenocarcinoma of the uterine cervix. There was 11$\%$ of late complication rates in LDR Group and 27$\%$ in HDR Group. There were no prognostic factors compared HDR with LDR group. The incidence of the late complication rate in HDR Group stage II, III was higher than that in LDR Group(16.7$\%$ vs. 31.6$\%$ in stage II, 11.1$\%$ vs. 35.3$\%$ In stage III, p>0.05). Although the incidence of radiation induced late complication rate was higher in HDR Group stage II and III patients than that in the LDR Group, statistical significance was not detected and within acceptable level. Conclusion : There was no difference in terms of 5-year survival rate and failure pattern in the patients with adenocarcinoma of the uterine cervix treated with HDR and LDR brachytherapy. Even late complication rates were higher in the HDR group It was an acceptable range. This retrospective study suggests that HDR brachytherapy seems to replace the LDR brachytherapy in the adenocarcinoma of the uterine cervix. However, further studies will be required to refine the dose rate effects.

• Radiation Oncology Journal
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• v.20 no.4
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• pp.323-327
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• 2002

Purpose : To evaluate the outcome of early stage non-small cell lung cancer patients who were treated with radiation therapy alone and define the optimal radiotherapeutic regimen for these patients. Materials and Methods : A retrospective review was peformed on patients with sage I or II non-small cell carcinoma of the lung that were treated at our institution between June, 1987 and May, 2000. A total of 21 patients treated definitively with radiation therapy alone were included in this study. The age of the patients ranged from 53 to 81 years with a median of 66 years. All the patients were male. The medical reasons for inoperability were lack of pulmonary reserve, cardiovascular disease, poor performance status, old age, and patient refusal in the decreasing order. Pathological evidence was not adequate to characterize the non-small cell subtype in two patients. Of the remaining 19 patients, 16 had squamous cell carcinoma and 3 had adenocarcinoma. Treatment was given with conventional fractionation, once a day, five times a week. The doses to the primary site ranged from 56 Gy to 59 Gy. No patients were lost to follow-up. Results : The overall survival rates for the entire group at 2, 3 and 5 years were 41, 30 and $21\%$, respectively. The cause specific survivals at 2, 3 and 5 years were 55, 36 and $25\%$, respectively. An intercurrent disease was the cause of death in two patients. The cumulative local failure rate at 5 years was $43\%$. Nine of the 21 patients had treatment failures after the curative radiotherapy was attempted. Local recurrences as the first site of failure were documented in 7 patients. Therefore, local failure alone represented $78\%$ of the total failures. Those patients whose tumor sizes were less than 4 cm had a significantly better 5 year disease free survival than those with tumors greater than 4 cm $(0\%\;vs\;36\%)$. Those patients with a Karnofsky performance status less than 70 did not differ significantly with respect to actuarial survival when compared to those with a status greater than 70 $(25\%\;vs\;26\%,\;p>0.05)$. Conclusion : Radiation therapy 리one is an effective and safe treatment for early stage non-small ceil lung cancer patients who are medically inoperable or refuse surgery. Also we believe that a higher radiation dose to the primary site could improve the local control rate, and ultimately the overall survival rate.

• Radiation Oncology Journal
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• v.13 no.4
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• pp.339-348
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• 1995

Purpose : Since 1983, authors have conducted a study to evaluate the effect of external radiation therapy and to determine affected factors in management of the patients with malignant obstructive jaundice due to porta hepatis metastasis from stomach cancer. Materials and Methods : Thirty two patients with malignant obstructive jaundice due to porta hepatis metastasis from gastric cancer were presented. We have analysed 23 patients who were treated with external radiation therapy of more than 3000cGy. The radiation dose, disease extent at developement of jaundice, total bilirubin levels before radiation therapy, differentiation of histology, combind treatment, intent of primary surgery, initial stage of gastric cancer were analyzed to determine affected factors in radiation therapy. External radiation therapy was delivered with a daily dose of 180-300cGy, 5 times a week fractionation using 4 MeV linear accelerator. The radiation field included the porta hepatis with tumor mass by the abdominal ultrasonography or CT scan. In twenty three patients received more than 3000cGy, total irradiation dose was ranged from 3000cGy to 5480cGy, median 3770cGy. Among 23 patients, 13 patients were delivered more than equivalant dose of TDF 65(4140cGy/23fx). Results : Among 23 patients, complete, partial and no response were observed in 13, 5, 5 patients, respectively. The median survival for all patients was 5 momths. The significant prolongation of median survival was observed in complete responders(11 months) as compared to partial and no responders(5 months, 5 months respectively) Out of 13 patients with complete response, 6 patients lived more than a year Among 13 patients receiving more than 4140cGy equivalent dose, complete, partial and no response were observed in 10, 2 and 1 patients, respectively. The median survival for all these patients was 9.5 months. The median survival for complete responders(10/13) was 11.5 months. Among 10 patients receiving less than 4140cGy equivalent dose, complete, partial and no response were observed in 3, 3, 4 patients, respetively. The median survival for all these patients was 4.3 months Therefore, the radiation dose affected the results of treatment. For the complete response with prolongation of survival duration, at least 4140cGy equivalant dose should be delivered to porta hepatis. In evaluation of the disease extent, 7 patients of 13 complete responders showed localized disease in porta hepatis or peripancreatic area, but all patients with partial and no response showed wide extensive disease or persistant disease of primary gastric cancer. Therefore. the patients with the localized disease were the higher probability of complete response and long term survival. This study suggested that the radiation dose and the disease extent at developement of jaundice affected in radiation therapy for malignant obstructive jaundice. There were no serious complications related to external radiation therapy. Conclusion : External radiation therapy only could achieve the palliative effect in the patients with malignant obstructive jaundice due to porta hepatis metastasis from stomach cancer. This study suggested that the prolongation of survival duration could be achived in complete responders and radiation dose, extent of disease affected the results of treatment of malignant obstructive jaundice.

• Radiation Oncology Journal
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• v.17 no.3
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• pp.195-202
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• 1999

Purpose : We peformed this study to evaluate the prognostic factors and the effect of induction chemotherapy in locally advanced non-small cell lung cancer (NSCLC). Materials and Methods : A retrospective analysis was done for 130 patients with locally advanced NSCLC treated with curative radiotherapy alone or induction chemo-radiotherapy from January 1986 to October 1996. Eighty-five patients were treated with radiotherapy alone, forty-five with induction chemotherapy and radiotherapy. Age, sex, performance status, histopathologic type, and stage were evenly distributed in both groups. The patients were treated with 6 MV or 10 MV X-ray. Conventional fractionation with daily fraction size 1$.8\~2.0$ Gy was done. Of the patients, 129 patients received total dose above 59.6 Gy ($56\~66$ Gy, median 60 Gy). Induction chemotherapy regimen were CAP (Cyclo-phosphamide, Adriamycin, Cisplatin) in 6 patients, MVP (Mitomycin, Vinblastine, Cisplatin) in 9 patients, MIC (Mitomycin, Ifosfamide Cisplatin) in 13 patients, and EP (Etoposide, Cisplatin) in 17 patients. Chemotherapy was done in $2\~5$ cycles (median 2). Results : Overall 1-, 2-, and 3-year survival rate (YSR) for all patients were $41.5\%,{\;}13.7\%,{\;}and{\;}7\%$, respectively (median survival time 11 months). According to treatment modality, median survival time, overall 1-, 2-, and 3-YSR were 9 months, $32.9\%,{\;}10.\5%,{\;}6\%$ for radiotherapy alone group, and 14 months, $57.8\%,{\;}20\%,{\;}7.6\%$ for induction chemotherapy group, respectively (f=0.0005). Complete response (CR) to overall treatments was $25\%$ (21/84) in radiotherapy alone and $40.5\%$ (17/42) in induction chemotherapy group (p=0.09). The Prognostic factors affecting overall survival were hemoglobin level (p=0.04), NSE (neuron-specific enolase) level (p=0.004), and respense to overall treatment(p=0.004). According to treatment modalities, NSE (neuron-specific enolase) (p=0.006) and response to overall treatment (p=0.003) were associated with overall survival in radiotherapy alone group, and response to overall treatment (p=0.007) in induction chemotherapy group. The failure Pattern analysis revealed no significant difference between treatment modalities. But, in patients with CR to overall treatment, distant metastasis were found in 11/19 patients with radiotherapy alone, and 3/13 patients with induction chemotherapy and radiotherapy (p=0.07). Locoregional failure patterns were not different between two groups (10/19 vs 6/13). Conclusion : Induction chemotherapy and radiotherapy achieved increased 2YSR compared to radiotherapy alone, At least in CR patients, there was decreased tendency in distant metastasis with induction chemotherapy. But, locoregional failures and long-term survival were not improved. Thus, there is need of more effort to increasing local control and further decreasing distant metastasis.

• Applied Biological Chemistry
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• v.14 no.1
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• pp.59-97
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• 1971

As a study on the cellulase of Myriococcum albomyces the culture media for enzyme formation and properties of its crude preparation were investigated and the crude enzyme preparation was further fractionated. The results are summarized as follows: 1. Wheat bran solid culture produced stronger activities of cellulase than rice bran or defatted soy bean meal solid culture. 2. Shaking culture with wheat bran, rice bran or defatted soy bean meal produced higher cellulase activities than solid culture with the corresponding media. 3. The enzyme formation was higher at $45^{\circ}C$ than at $37^{\circ}C$ or $50^{\circ}C$ regardless of the kind of culture medium. 4. The formation of CMCase activity was more promoted by organic nitrogen source than inorganic nitrogen source. 5. The formation of cellulase activities were increased 1.5 to 3.0-fold by adding CMC, Avicel or cellulose powder as an inducer into 5% wheat bran basal medium. 6. Cellulase production using a tank culture procedure with addition of CMC or Avicel as an inducer was the highest at fifth day and thereafter decreased slightly. 7. The crude enzyme preparation showed pH optimum in 4.0 to 4.5, and pH stability in the range of 3.5 to 8.0. Optimum temperature for the activity was $65^{\circ}C$ which was higher than among other cellulases and it was stable at $60^{\circ}C$ for 120 minutes. 8. Dialyzed crude enzyme was activated by $Ca^{++}$ and $Mg^{++}$, but inhibited by $Hg^{++}$, $Cu^{++}$ and $Ag^{+}$. 9. Four different types of cellulase, i. e., fraction I, fraction II-a, fraction II-b, and fraction III were purified from the culture filtrate of Myriococcum albomyces through a sequence of ammonium sulfate fractionation, and elution chromatography on DEAE-Sephadex A-25, Amberlite CG-25 type 2 and hydroxyapatite columns. 10. These four cellulase fractions were showed to be homogenous by electrophoresis and ultracentrifugation and also gave a typical ultraviolet absorption spectrum of protein. 11. Four purified fraction showed different specificity toward substrates, fraction I has a stronger activity toward Avicel, cellulose powder, and gauze than that of other cellulase fractions. Fraction II-a had a powerful activity toward cellobiose but it was almost inactive agaisnt fibrous cellulose contrary to fraction I. On the contrary, the main component fraction II-b had a fairly higher activity on CMC and Avicel. Activity of fraction II-b toward cellobiose was about one-third of that of fraction II-a and activity on Avicel was lower than that of fraction I. Fraction III had a more powerful activity in decreasing viscosity of CMC. 12. Final hydrolysis products of fibrous cellulose by each fraction were cellobiose and glucose. Whereas oligosaccharides were predominant in the early stage of hydrolysis, prolonged reaction produced more glucose than cellobiose. Fraction I and fraction II-a acted synergically on Avicel. 13. Optimum pH for the activities of cellulase fraction I, fraction II-a, fraction II-b and fraction III were found to be 5.5, 5.0, 4.0 and $4.0{\sim}4.5$, respectively. These fractions were found to be stable in the range of pH $3.0{\sim}7.5$. 14. Optimum temperature for the activities of fraction I, fraction II-a, fraction II-b, and fraction III were $50^{\circ}C$, $55^{\circ}C$, $60^{\circ}C$ and $55^{\circ}C$, respectively. No less of activity was found by heating 120 minutes at $55^{\circ}C$ and fraction II-a was more stable than the others at $60^{\circ}C$. 15. Fraction I and fraction II-b were activated by $Ca^{++}$ and $Mg^{++}$ but inhibited by $Hg^{++}$ and $Ag^{+}$.

• Radiation Oncology Journal
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• v.26 no.4
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• pp.195-203
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• 2008

Purpose: To investigate the treatment outcome and failure patterns after definitive chemoradiation therapy in locally advanced, unresectable esophageal cancer. Materials and Methods: From February 1994 to December 2002, 168 patients with locally advanced unresectable or medically inoperable esophageal cancer were treated by definitive chemoradiation therapy. External beam radiation therapy (EBRT) ($42{\sim}46\;Gy$) was delivered to the region encompassing the primary tumor and involved lymph nodes, while the supraclavicular fossa and celiac area were included in the treatment area as a function of disease location. The administered cone-down radiation dose to the gross tumor went up to $54{\sim}66\;Gy$, while the fraction size of the EBRT was 1.8-2.0 Gy/fraction qd or 1.2 Gy/fraction bid. An optional high dose rate (HDR) intraluminal brachytherapy (BT) boost was also administered (Ir-192, $9{\sim}12\;Gy/3{\sim}4\;fx$). Two cycles of concurrent FP chemotherapy (5-FU $1,000\;mg/m^2$/day, days $2{\sim}6$, $30{\sim}34$, cisplatin $60\;mg/m^2$/day, days 1, 29) were delivered during radiotherapy with the addition of two more cycles. Results: One hundred sixty patients were analyzable for this review [median follow-up time: 10 months (range $1{\sim}149$ months)). The number of patients within AJCC stages I, II, III, and IV was 5 (3.1%), 38 (23.8%), 68 (42.5%), and 49 (30.6%), respectively. A HDR intraluminal BT was performed in 26 patients. The 160 patients had a median EBRT radiation dose of 59.4 Gy (range $44.4{\sim}66$) and a total radiation dose, including BT, of 60 Gy (range $44.4{\sim}72$), while 144 patients received a dose higher than 40 Gy. Despite the treatment, the disease recurrence rate was 101/160 (63.1%). Of these, the patterns of recurrence were local in 20 patients (12.5%), persistent disease and local progression in 61 (38.1%), distant metastasis in 15 (9.4%), and concomitant local and distant failure in 5 (3.1%). The overall survival rate was 31.8% at 2 years and 14.2% at 5 years (median 11.1 months). Disease-free survival was 29.0% at 2 years and 22.7% at 5 years (median 10.4 months). The response to treatment and N-stage were significant factors affecting overall survival. In addition, total radiation dose (${\geq}50\;Gy$ vs. < 50 Gy), BT and fractionation scheme (qd. vs. bid.) were not significant factors for overall survival and disease-free survival. Conclusion: Survival outcome after definitive chemoradiation therapy in unresectable esophageal cancer was comparable to those of other series. The main failure pattern was local recurrence. Survival rate did not improve with increased radiation dose over 50 Gy or the use of brachytherapy or hyperfractionation.

• Radiation Oncology Journal
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• v.23 no.2
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• pp.61-70
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• 2005

Purpose: Uterine cervix cancer is one of the most prevalent women cancer in Korea. We analysed published papers in Korea with comparing Patterns of Care Study (PCS) articles of United States and Japan for the purpose of developing and processing Korean PCS. Materials and Methods: We searched PCS related foreign-produced papers in the PCS homepage (212 articles and abstracts) and from the Pub Med to find Structure and Process of the PCS. To compare their study with Korean papers, we used the internet site 'Korean Pub Med' to search 99 articles regarding uterine cervix cancer and radiation therapy. We analysed Korean paper by comparing them with selected PCS papers regarding Structure, Process and Outcome and compared their items between the period of before 1980's and 1990's. Results: Evaluable papers were 28 from United States, 10 from the Japan and 73 from the Korea which treated cervix PCS items. PCS papers for United States and Japan commonly stratified into $3\~4$ categories on the bases of the scales characteristics of the facilities, numbers of the patients, doctors, Researchers restricted eligible patients strictly. For the process of the study, they analysed factors regarding pretreatment staging in chronological order, treatment related factors, factors in addition to FIGO staging and treatment machine. Papers in United States dealt with racial characteristics, socioeconomic characteristics of the patients, tumor size (6), and bilaterality of parametrial or pelvic side wail invasion (5), whereas papers from Japan treated of the tumor markers. The common trend in the process of staging work-up was decreased use of lymphangiogram, barium enema and increased use of CT and MRI over the times. The recent subject from the Korean papers dealt with concurrent chemoradiotherapy (9 papers), treatment duration (4), tumor markers (B) and unconventional fractionation. Conclusion: By comparing papers among 3 nations, we collected items for Korean uterine cervix cancer PCS. By consensus meeting and close communication, survey items for cervix cancer PCS were developed to measure structure, process and outcome of the radiation treatment of the cervix cancer. Subsequent future research will focus on the use of brachytherapy and its impact on outcome including complications. These finding and future PCS studies will direct the development of educational programs aimed at correcting identified deficits in care.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.46-52
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• 2009

Deposition of atmospheric N that is depleted in $^{15}N$ has shown to decrease N isotope ratio ($^{15}N/^{14}N$,expressed as ${\delta}^{15}N$) of forest samples such as tree rings, foliage, and total soil-N. However, its effect on ${\delta}^{15}N$ of mineral soil-N which is biologically active N pool has never been tested. In this study, ${\delta}^{15}N$ of mineral N($NH{_4}^+$ and $NO_3{^-}$) in forest soils from organic and two depths of mineral soil layers (0 to 20 cm and 20 to 40cm depth) of Pinus densiflora stands located at two distinct areas (rural and industrial areas) in southern Korea was analyzed to investigate if there is any difference in ${\delta}^{15}N$ of mineral N between these areas. We also evaluated potential N loss of the study sites using ${\delta}^{15}N$ of mineral N. Across the soil layers, the ${\delta}^{15}N$ of $NH{_4}^+$ ranged from +8.9 to +24.8‰ in the rural area and from +4.4 to +13.8‰ in the industrial area. Soils from organic layer (+4.4‰) and mineral layer between 0 and 20 cm (+13.8‰) of industrial area showed significantly lower ${\delta}^{15}N$ of $NH{_4}^+$ than those of rural area (+8.9 and +24.3‰, respectively), probably indicating the greater contribution of $^{15}N$-depleted $NH{_4}^+$ from atmospheric deposition to forest in the industrial area than in the rural area. Meanwhile, ${\delta}^{15}N$ of $NO_3{^-}$ was not different between the rural and industrial areas, probably because ${\delta}^{15}N$ of $NO_3{^-}$ is more likely to be altered by the N loss that causes $^{15}N$ enrichment of the remaining soil N pool. Compared with the ${\delta}^{15}N$ of soil mineral N reported by other studies (from -10.9 to +15.6‰ for $NH{_4}^+$ and -14.8 to +5.6‰ for $NO_3{^-}$), the ${\delta}^{15}N$ observed in our study was substantially high, suggesting that the study sites are more subject to the N loss. It was concluded that $NH{_4}^+$ rather than $NO_3{^-}$ can conserve the ${\delta}^{15}N$ signature of atmospheric N deposition in forest ecosystems.