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991.
OBJECTIVE: To evaluate the small bowel displacement system (SBDS)-assisted intensity-modulated radiation therapy (IMRT) for cervical cancer patients. METHODS: Ten consecutive patients that received radiation therapy for uterine cervical cancer, with the SBDS, between January and May 2003, were included in this study. The SBDS consists of a customized Styrofoam compression device, which displaces the small bowel out of the radiation fields and an individualized immobilization abdominal board. Computed tomography (CT) scans were taken in the prone position, both with and without the SBDS. IMRT planning was performed for both CT sets using 15 MV photon beams. The dose distributions in the target volumes and the organs at risk, with and without the SBDS, were compared. The complexity of both the IMRT plans was evaluated by comparing the monitor units (MUs) and multi-leaf collimator (MLC) segment numbers of the plans. RESULTS: The SBDS significantly reduced the small bowel volume within the pelvic radiation field. The mean irradiated small bowel volume, with the SBDS, was 61.46 +/- 4.97% (53.4-97.1%) smaller than the conventional IMRT. The SBDS-assisted IMRT plan was superior to the conventional one in terms of the dose homogeneity in the planning target volume (PTV) but not significantly different in the rectum and bladder. The mean MUs and MLC segment numbers, with the SBDS, were 26.2% and 31.65% lower than the values without the SBDS, respectively (P < 0.0001 for MUs and MLCs). CONCLUSIONS: The SBDS-assisted IMRT is superior to conventional IMRT in terms of the dose homogeneity of PTV and in sparing of the small bowel, which potentially allows dose escalation by further reducing the small bowel complications.  相似文献   
992.
AIM: We investigated the cumulative probability of ongoing pregnancy in intracytoplasmic sperm injection (ICSI) cycles. METHODS: During a period of 6 years, 519 ICSI cycles were performed in 260 infertile couples at the Seoul National University Hospital. The cumulative rate of ongoing pregnancy (> or =12 weeks of gestation) was estimated by the Kaplan-Meier method. RESULTS: The cumulative ongoing pregnancy rate was 54.9% after six consecutive cycles of ICSI. The age of the female had a significant impact; after five consecutive cycles, cumulative ongoing pregnancy rate was 61.8% in < or =30 years of age, 51.7% in 31-35, and 15.3% in > or =36. There was no significant difference in the cumulative ongoing pregnancy rate between groups with severe male factor and previous unexplained low fertilization rate (< or =20%). Among the severe male factor group, cumulative ongoing pregnancy rate was not different according to the methods of sperm retrieval (surgically retrieved or ejaculated). CONCLUSION: Intracytoplasmic sperm injection could be applied successfully both to severe male factor and patients with previous unexplained low fertilization rate. The origin of spermatozoa does not affect ICSI outcome in terms of cumulative probability of ongoing pregnancy.  相似文献   
993.
BACKGROUND/AIMS: Reactivation of hepatitis B virus (HBV) replication is a well-known complication in cancer patients receiving chemotherapy. The aims of this study were to determine the incidence of HBV reactivation in hepatocellular carcinoma (HCC) patients undergoing transarterial chemo-lipiodolization, and to clarify factors contributing to HBV reactivation. METHODS: From April 2001 to September 2002, 146 HBsAg positive patients newly diagnosed as HCC were enrolled in the study. Among these, 83 patients underwent transarterial chemo-lipiodolization using epirubicin and/or cisplatin, and 63 received other treatments. RESULTS: In total, HBV reactivation occurred in 30 (20.5%) patients (28 with chemo-lipiodolization and 2 with other treatments), and of the 30 patients, 19 (13.0%) (18 with chemo-lipiodolization and 1 with other treatments) developed hepatitis. Chemo-lipiodolization was significantly correlated with a higher incidence of hepatitis attributed to HBV reactivation than other treatments (21.7% vs. 1.6%, P<0.001), irrespective of HBeAg or HBV DNA. Among 83 patients undergoing chemo-lipiodolization, HBV reactivation occurred in 28 (33.7%) patients, and HBeAg seropositivity was the only independent predictor of HBV reactivation (P=0.013). Three (10.7%) of them died of hepatic decompensation resulting from HBV reactivation. CONCLUSIONS: Transarterial chemo-lipiodolization can reactivate HBV, and HBeAg-positive HCC patients receiving chemo-lipiodolization should be closely monitored for HBV reactivation.  相似文献   
994.
BACKGROUND/AIMS: Little is known of the characteristics of gastric adenocarcinoma after renal transplantation. This study was performed to find out the incidence and clinicopathological features of gastric adenocarcinoma after renal transplantation in an endemic area for gastric cancer. METHODOLOGY: Between April 1979 and March 2001, fourteen gastric adenocarcinoma patients (0.7%) out of 2000 renal transplant recipients in a single institute were retrospectively reviewed. RESULTS: Gastric adenocarcinoma was identified in 14 recipients (8 males and 6 females; mean age 47.6 years) about 60 months after renal transplantation. Four patients had early gastric cancer; ten patients had cancer in an advanced stage. Eleven patients underwent surgical resection, while three with distant metastasis were treated symptomatically. There was no postoperative mortality. Seven patients survived without evidence of recurrence, whereas four died of recurrence and three of gastric cancer progression. CONCLUSIONS: Renal transplant recipients are at increased risk of gastric adenocarcinoma, the most common malignancy in Korea. With curative surgery, favorable prognosis can be anticipated when the diagnosis is made at an early stage. Regular endoscopic examination for early diagnosis is recommended during the follow-up period after renal transplantation in a gastric cancer endemic area.  相似文献   
995.
Covered retrievable expandable nitinol stents were successfully placed in nine patients with tuberculous bronchial strictures refractory to balloon dilation. Complications included stent migration (n = 1) and tissue hyperplasia at the proximal portion of the stent (n = 2). During the follow-up period (5-52 months), stricture recurred in three of five patients (60%) after temporary stent placement for 2 months, whereas stricture did not recur in the other four patients after temporary stent placement for 6 months. Temporary placement of covered retrievable stents appears to be an effective method for the treatment of patients with tuberculous bronchial strictures refractory to balloon dilation.  相似文献   
996.

Objective

This study was undertaken for the purpose of describing the CT features of intra-abdominal extra-hepatic metastases from gastrointestinal stromal tumors in patients who were treated with imatinib.

Materials and Methods

Eleven patients with intra-abdominal extra-hepatic metastases from gastrointestinal stromal tumors, who were treated with imatinib between May 2001 and December 2003, were included in this study. The clinical findings and CT scans were retrospectively reviewed. The metastatic lesions were assessed according to the location, size (greatest diameter), attenuation, and the enhancing pattern before and after imatinib treatment.

Results

Prior to the treatment, the sizes and attenuation values of the metastatic lesions ranged from 5 to 20 cm and from 63 to 131 H, respectively. The metastatic lesions showed a heterogeneous enhancement pattern on the contrast-enhanced CT scans. After the treatment, the metastatic lesions became smaller in all 11 patients, and the corresponding attenuation value ranged from 15 to 51 H. The metastatic lesions became homogeneous and cystic in appearance on the follow-up CT scans, mimicking ascites.

Conclusion

Intra-abdominal extra-hepatic metastases of patients with gastrointestinal stromal tumors treated with imatinib may appear as well-circumscribed cystic lesions on contrast-enhanced CT. These metastases are likely to become smaller and resemble ascites, but may persist indefinitely on the follow-up CT.  相似文献   
997.
998.
Kim YJ  Jeon SH  Huh JS  Chang SG 《European urology》2004,46(6):748-752
OBJECTIVE: The occurrence of primary carcinoma of the ureteral stump after nephrectomy is rare. In this study, we evaluated the clinical characteristics of ureteral stump tumors after nephrectomy for benign renal disease. METHODS: During a 16-year period, 318 consecutive patients underwent simple nephrectomy for benign renal disease (216 cases) or for donation (102 cases). Eight of these 318 patients diagnosed as having an ureteral stump tumor were treated by ipsilateral ureterectomy with cuff excision of the bladder. Pathologic findings, tumor stages, and clinical characteristics were analyzed. RESULTS: The eight ureteral stump tumors comprised; 6 transitional cell carcinomas (TCCs) and 2 squamous cell carcinomas (SCCs). The mean interval between nephrectomy and ureteral stump tumor diagnosis was 76.5 months. Six of the 8 patients had pyonephrosis and two renal tuberculosis as original renal diseases. Four of the 6 TCCs were stage T1 and 2 stage T2. There was no concomitant bladder tumor at stump tumor diagnosis. Hematuria was the major presenting symptom in 3 of the 8 patients and 4 patients were diagnosed by follow-up imaging study. Two of the 6 ureteral stump TCC patients developed bladder TCC during follow-up. The 5-year survival rate of patients with ureteral stump tumor was 37.5%. T1G1 TCC was associated with a better survival than T2 or G2 TCC. No ureteral stump tumor occurred in cases of donor nephrectomy. CONCLUSION: This study demonstrate, that long-term closed observation is needed to detect ureteral stump tumor, particularly in patients that have undergo nephrectomy for a long-standing inflammatory renal disease such as pyonephrosis or tuberculosis. Hematuria is a major presenting symptom of ureteral stump tumor. However, a follow-up imaging study is also important for ureteral stump tumor detection. The prognosis is poor in cases developing ureteral stump SCC, bladder tumor recurrence, or a high-grade ureteral tumor.  相似文献   
999.
1000.
BACKGROUND AND PURPOSE: Clinical cerebral-fat embolism shows both reversible and irreversible changes. We used MR imaging to investigate the reversibility of embolized lesions induced with a fat-emulsion technique and to evaluate the histologic findings. METHODS: A fat emulsion was made with 0.05 mL of triolein and 20 mL of normal saline and vigorous to-and-fro movement through a three-way stopcock. In 50 cats, the internal carotid artery was infused with the fat emulsion. Cats were divided into six groups on the basis of time delay after embolization: 1 hour; 1 and 4 days; and 1, 2, and 3 weeks. MR imaging and histologic examination were performed at these times. RESULTS: Embolized lesions were hyperintense on T2-weighted images, isointense or mildly hyperintense on diffusion-weighted images, isointense on apparent diffusion coefficient maps, and enhancing on gadolinium-enhanced T1-weighted images at 1 hour. These MR imaging findings were less evident at day 1 and reverted to normal after day 4 (isointense on all images). Electron microscopy showed minimal findings in the cortical lesion in groups 1 and 2 (group 1 at 1 hour and group 2 at 1 hour and 1 day). Light microscopic findings revealed evidence of necrosis-small focal gliosis and demyelination in the periventricular white matter-in only one cat. The number of intravascular fat globules was not significantly different between groups, as visualized by oil red O staining. CONCLUSION: Cerebral-fat embolism induced by a triolein emulsion revealed reversible MR findings and minimal histologic findings.  相似文献   
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