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1.
Chordoma: role of radiation therapy   总被引:4,自引:0,他引:4  
The treatment of 21 patients with a diagnosis of chordoma seen over a 20-year period is described. The 13 men and eight women (ratio 1.6:1) ranged in age from 7 to 82 years (average, 50 years). Eleven chordomas arose from the clivus; the others originated in the sacral region (three patients), thoracic spine (one), cervical spine (three), and lumbar spine (three). Primary treatment consisted of surgery, reserving radiation therapy for recurrence in the majority of patients. Radiation doses, delivered with megavoltage equipment, ranged between 5,000 cGy delivered over 5 weeks and 6,600 cGy over 6 1/2 weeks. Irradiation produced significant tumor control, with remission of symptoms from 1 to 6 years. The combination of high-dose radiation therapy and complete or subtotal surgical resection offers the best chance for prolonged survival in this group of patients.  相似文献   

2.
Forty-nine patients with locally advanced carcinoma of the pancreas were treated in a randomized, prospective study comparing definitive helium ion radiation therapy with conventional split-course megavoltage photon irradiation. Patients in each treatment arm underwent exploratory staging laparotomy followed by concurrent radiation therapy and 5-fluorouracil chemotherapy. Patients treated with photons received 6,000 cGy over a period of 10 weeks; patients treated with helium irradiation received a 6,000-7,000-cGy-equivalent dose over a period of 8-9 weeks. There was no significant difference in overall survival between patients in the two treatment arms (P = .29). Patients treated with helium ions had a slightly longer median survival (7.8 months) than the photon-treated patients (6.5 months). Local control rates were slightly higher in the helium-treated patients (10% vs 5%). Complications included one chemotherapy-related death. Four of the five helium-treated patients who survived longer than 18 months died of local failure without distant metastases. These results suggest that more aggressive local therapy could result in improved survival in helium-treated patients.  相似文献   

3.
Fourteen patients with transitional cell carcinoma of the urinary bladder were treated with 4,000 cGy of pelvic irradiation concurrent with two 96-hour infusions of 5-fluorouracil (5-FU). Three weeks after completion of this regimen, patients underwent repeat cystoscopy and deep-muscle biopsy at the site of their original neoplasms. Eight of 14 (57%) had no tumor left in the biopsy specimen, and they received an additional course of chemotherapy and radiation therapy to a total dose of 4,400 cGy to the pelvis and 6,000 cGy to the bladder. Five of the 14 had residual tumor in the biopsy specimen (one did not undergo biopsy) and went on to planned cystectomy. Two of the five had no tumor in the cystectomy specimen. Overall, ten of the 14 patients (71%) have been downstaged to a condition of P0 (no tumor) following 4,000 cGy and two courses of 5-FU. Of eight patients with retained bladders, seven remain well at a median follow-up of 7 months. At a range of follow-up of 3-21 months and a median of 7 months, 13 of 14 patients remain tumor-free. This regimen results in a greater percentage of downstaging than conventional irradiation alone, and may allow bladder preservation for those with radiation therapy- and chemotherapy-responsive tumors.  相似文献   

4.
Rich  TA; Weiss  DR; Mies  C; Fitzgerald  TJ; Chaffey  JT 《Radiology》1985,156(2):527-531
Twenty-six patients with small cancers limited to the lower two-thirds of the rectum were treated with conservative surgery and radiation therapy (XRT). The selection factors for this approach were age, refusal of a permanent colostomy, or the high risk of local recurrence because of inadequate surgical margin or palpable residual tumor after local surgical treatment alone. In patients treated with local excision or fulguration followed by XRT, there was a 6% local failure rate (one in 17); in 16 of 17 patients receiving radiation doses above 4,500 cGy, the local control was complete for follow-up periods of 6 months to 7 years. In nine patients treated with XRT for residual tumor, local failure occurred in five (56%). The disease-free survival for those without residual tumor versus those with residual tumor was 88% and 44%, with median follow-up periods of 20 and 23 months, respectively. Serious late complications occurred only if total doses were greater than 6,300 cGy. Local excision combined with XRT proved to be a safe alternative to radical surgery in selected patients and resulted in excellent local control while allowing preservation of anal sphincter function.  相似文献   

5.
Giant cell tumors of bone: treatment with radiation therapy   总被引:1,自引:0,他引:1  
Seider  MJ; Rich  TA; Ayala  AG; Murray  JA 《Radiology》1986,161(2):537-540
Records of 15 patients with giant cell tumor of bone treated with radiation therapy over a 35-year period were reviewed; ten patients for whom follow-up information was available constituted the study group. One patient was treated by means of orthovoltage equipment only, a second, by both orthovoltage and megavoltage equipment (cobalt 60). The remaining eight were all treated with megavoltage to doses of 40-52 Gy in 24-30 fractions. Seven patients are alive without disease, with an average survival of 192 months (range, 48-360 months). Three patients died of uncontrolled local and distant disease (average survival, 52 months; range, 23-99 months): one with metastasis in the lungs at time of treatment and two after treatment. Although incidence of lung metastasis appears high, it may be due to patient selection because chemotherapy had failed in all three. Complications from irradiation in one surviving patient required surgical closure of a dural fistula 19 years after treatment. No radiation-induced sarcomatous transformations of controlled tumors were noted. These data suggest that giant cell tumor of bone can be well controlled by radiation therapy. Megavoltage irradiation should be considered in treating local disease not easily controlled by surgery in the axial skeleton. Complications are minimal, and normal function can be preserved in the treated areas.  相似文献   

6.
PURPOSE: To describe a novel use of high-dose-rate intravascular brachytherapy in the first reported case of macroscopic metastatic rectal adenocarcinoma within a peripheral vein. METHODS AND MATERIALS: Following thrombolytic therapy to ablate an overlying venous thrombosis, a vascular stent was deployed across the entire length of the tumor. Using the stent as a target, 4300 cGy was delivered to the tumor via megavoltage external beam radiation. This was followed by two weekly intravascular high-dose-rate 192Ir brachytherapy applications of 400 cGy each. RESULTS: There is no evidence of recurrence in the treated vein at 43 months of follow-up. CONCLUSIONS: In this unique case, a combination of external beam radiation therapy and intravascular brachytherapy provided effective control of a solitary intravascular metastasis from rectal carcinoma.  相似文献   

7.
PURPOSE: Most malignant meningiomas will recur following surgical resection only. The role of irradiation and radiation dose levels is poorly defined. This study reviews a single institution experience using both, conventional and high doses > or = 60 Gy/CGE radiation regimen. PATIENTS AND METHODS: Between 1974 and 1995 16 patients with histologically proven malignant meningioma underwent radiation therapy (RT). Age at diagnosis ranged between 6 and 79 years (median: 49 years). Three patients reported previous irradiation to the head at least 14 years prior to diagnosis. Ten patients were treated for primary, and 6 patients for recurrent disease. Six patients underwent gross total and 10 patients subtotal resection (Table 1). RT was delivered using conventional, megavoltage photons or combined 160 MeV proton and photon irradiation. Except 1 patient, who died during RT, the radiation doses ranged between 40 and 70 Gy/CGE (= Cobalt Gray Equivalent) (median: 58 Gy/CGE, Table 2). RESULTS: With median observation time of 59 months (range: 10 to 155 months), actuarial local control rates at 5 and 8 years were 52% and 17%, respectively. Target doses > or = Gy/CGE resulted in significantly improved tumor control (100%) compared to < 60 Gy/CGE (17%) (p = 0.0006, Table 3 and Figure 1). Improved local control translated also in increased overall survival: 87% (> or = 60 Gy/CGE) versus 15% (< 60 Gy/CGE) at 5 years (p = 0.025, Figure 2). At time of analysis, 6/16 patients (38%) were alive. Two patients developed symptomatic brain damage at doses of 59.3 and 72 Gy/CGE. CONCLUSION: Conformal, radiation therapy with target doses > or = 60 Gy/CGE, in this study by use of combined proton and photon irradiation, can significantly improve chances of long-term local control and survival for patients diagnosed with these challenging tumors.  相似文献   

8.
PurposeTo analyze initial experience with computed tomography–guided high-dose-rate brachytherapy (CT-HDRBT) ablation of breast cancer liver metastases (BCLM).Materials and MethodsBetween January 2008 and December 2010, 37 consecutive women with 80 liver metastases were treated with CT-HDRBT in 56 sessions. Mean age was 58.6 years (range, 34–83 y). Treatment was performed by CT-guided applicator placement and high-dose-rate brachytherapy with an iridium-192 source. The mean radiation dose was 18.57 Gy (standard deviation 2.27). Tumor response was evaluated by gadoxetic acid–enhanced liver magnetic resonance (MR) imaging performed before treatment, 6 weeks after treatment, and every 3 months thereafter.ResultsTwo patients were lost to follow-up; the remaining 35 patients were available for MR imaging evaluation for a mean follow-up time of 11.6 months (range 3–32 mo). Mean tumor diameter was 25.5 mm (range 8–74 mm). Two (2.6%) local recurrences were observed after local tumor control for 10 months and 12 months. Both local progressions were successfully retreated. Distant tumor progression (new metastases or enlargement of nontreated metastases) occurred during the follow-up period in 11 (31.4%) patients. Seven (20%) patients died during the follow-up period. Overall survival ranged from 3–39 months (median 18 months).ConclusionsCT-HDRBT is a safe and effective ablative therapy, providing a high rate of local tumor control in patients with BCLM.  相似文献   

9.
Myelopathy is a feared consequence of radiation therapy. Risk factors are multifocal; therefore, total dose calculation is crucial. We evaluated the contribution of scatter radiation to obtain an accurate cumulative spinal cord dose. Twenty patients undergoing three field head and neck radiation by Cobalt or 6 MV Linac had a total cord dose calculated from direct and scatter radiation. The cord was removed from the radiation field at tumor doses no higher than 4,400 cGy. Total tumor dose ranged from 5,400-7,400 cGy (mean 6060). All patients achieved the prescribed dose and none were lost to follow up (mean 36 months). It was found that scatter radiation can contribute as much as 20% extra dose to the spinal cord. Mean extra dose was 9% (range 1%-20%). This additional dose ranged from 52-810 cGy (mean 339 cGy). No apparent difference was seen with Cobalt or Linac source. Our conclusion was that significant additional dose is delivered to the spinal cord by scatter radiation and that scatter may contribute more to the development of myelopathy than previously believed.  相似文献   

10.
PURPOSE: To perform and assess the effectiveness of local excision of recurrent tumor followed by postoperative pulse dose rate (PDR) brachytherapy. MATERIALS AND METHODS: From 1994 to 2000, 17 patients who had small recurrent breast carcinomas after initially undergoing breast-conserving therapy (BCT), which included postoperative radiation therapy, were treated with local tumor excision and PDR brachytherapy. Recurrences occurred at a median time of 50 months (range, 11-208 months) after primary treatment. Eight patients underwent a combination of PDR brachytherapy (total dose range, 12.5-28.0 Gy) and external-beam radiation therapy (EBT) (total dose range, 12-30 Gy). Nine patients underwent radiation therapy with 40.2-50.0-Gy PDR brachytherapy only. The prescribed radiation dose was 0.5-1.0 Gy per pulse. Patients were examined for local tumor control and treatment-related side effects. RESULTS: Twelve of 17 patients had no local tumor at a median follow-up time of 59 months (range, 20-84 months); two of these patients showed signs of having distant disease. One patient died after a cerebral stroke without evidence of tumor. Four women treated with combined EBT and brachytherapy had secondary local tumor recurrences 4, 8, 8, and 11 months after therapy and had to undergo mastectomy. Despite having undergone radiation therapy previously, patients had side effects limited to moderate (grade 1-2) fibrosis. CONCLUSION: Local tumor excision combined with PDR brachytherapy for small local-regional tumor recurrences after primary BCT is feasible and well tolerated and might obviate mastectomy. Preliminary experiences are encouraging. Further studies are required for appropriate patient selection.  相似文献   

11.
BACKGROUND: The localized prostate cancer can be treated curatively by radiation therapy. The combined treatment of external beam irradiation and HDR-Iridium 192 remote brachytherapy allows higher radiation doses within the tumor without increasing radiation sequelae. PATIENTS AND METHODS: Patients of our clinic have been treated with this combined procedure since 1991. Between 1991 and 1994 15 patients received 2 x 9 Gy of high-dose-rate brachytherapy, followed by 36 Gy external beam irradiation (group A). Because of the frequent local failures in group A, the reference dose of external beam irradiation was increased to 50.4 Gy after brachytherapy between 1994 and 1996. RESULTS: Seven of 15 patients (47%) in group A developed a local recurrence after a median of 17 (13 to 30) months. In group B (20 patients) local failure occurred in 3 patients (15%) after 11, 16 and 32 months. CONCLUSION: The combined radiation therapy of localized prostate cancer cannot substitute radical prostatectomy completely, but it is a promising alternative in the curative treatment in selected patients.  相似文献   

12.
Thirty-five patients with low-lying rectal adenocarcinoma have been treated with intracavitary radiation (Papillon's technique). Twenty-three were treated for cure and 12 for palliation. The indications for curative intracavitary radiation were mobile polypoid tumors, less than 3 cm in diameter, with Broder's Grades I and 2 differentiation lying less than 11 cm from the anal verge. Doses between 2 000 and 4 000 cGy were delivered to a total of 7 000 to 20 000 cGy with complete resolution of the tumors. Eighty-seven per cent in the curative group are alive and well up to 42 months after treatment with a minimum follow-up of six months. Of the 23 patients treated for cure, three patients had recurrences within 18 months of therapy. Two of the three patients are alive following surgery. The third patient died in the postoperative period. The results of intracavitary radiation are comparable to ablative surgery and avoid a permanent colostomy. Age, frailty, or other medical conditions do not preclude this treatment. Anesthesia and hospitalization are not required. This method can also be used for palliation of recurrent tumors and in patients who are unsuitable for surgery.  相似文献   

13.
Postoperative radiation therapy in the management of lung cancer   总被引:1,自引:0,他引:1  
Postoperative radiation therapy for lung cancer is still controversial. In a 9-year period, 69 patients with non-oat-cell carcinoma of the lung (16% stage I, 26% stage II, and 58% stage III) received such therapy. The radiation dose was less than 5,000 cGy in 42 patients, 5,000-5,900 cGy in 16, and 6,000 cGy or more in 11; follow-up ranged from 24 to 64 months. Actuarial survival at 2 and 4 years was 50% and 16%, respectively, for squamous cell carcinoma, and 40% and 26% for adenocarcinoma. The 5-year survival for stages I, II, and III cancer was 29%, 17%, and 19%, respectively. Histologic findings and type of surgery did not affect survival, but the radiation dose apparently did. The 3-year survival for patients who received less than 6,000 cGy was 35%, compared with 73% for patients who received higher doses. In eight patients, treatment failed within the irradiated volume: all had received doses of less than 6,000 cGy, and the volume in three was judged to be inadequate.  相似文献   

14.
Twenty-three patients with advanced untreated head and neck cancer, nine patients with recurrent cancer, and six patients with recurrent cancer who underwent surgery and had postoperative persistence of tumor were treated with three 2-week courses of irradiation (1,500 cGy in 10 fractions each) concurrently with cisplatin and a 5-day infusion of 5-fluorouracil. A fourth 2-week course of irradiation (2,000 cGy in 10 fractions) brought the final tumor dose to 6,500 cGy. Twenty patients in the untreated group and three patients in the recurrent group (33%) had a complete response. There were 10 local recurrences in the untreated group (43%), seven in the recurrent group (78%), and three in the persistent group (50%). At 17 months after the start of treatment, the survival rate for the untreated patients was 51%, for the patients in the recurrent group it was 11%, and for the patients in the persistent group it was 20% (P = .03). Most patients experienced toxicity, including nausea, vomiting, weight loss, and mucositis. Clinical trials are necessary to determine whether simultaneous chemotherapy and radiation therapy is an improved method of treatment for advanced head and neck cancer.  相似文献   

15.
PURPOSE: We evaluated the outcome of radiation therapy for maxillary sinus carcinoma treated in our institution. MATERIALS AND METHODS: From 1984 to 2001, 48 patients with maxillary sinus carcinoma were irradiated with or without chemotherapy and surgery. Patients ranged from 20-89 years of age (median, 68 years) and included 29 men and 19 women. The clinical T factors for these patients, according to the UICC classification (1997), were T2(n = 2), T3(n = 13), and T4(n = 29). Lymph node involvement was observed in 13 patients. The follow-upperiod ranged from 2.5 to 150 months (median, 25 months). The total radiotherapy dose ranged from 40 Gy to 72.8 Gy. Forty-three patients underwent surgery. Intra-arterial chemotherapy was delivered in 39 patients, and systemic chemotherapy was delivered in 7 patients. Fourteen patients were classified as "unresected" (radiation therapy with or without antrostomy), and 34 patients as "resected" (partial, total, or extended total maxillectomy with pre- or postoperativeirradiation). RESULTS: The 5-year overall survival rate(OS), cause-specific survival rate(CSS), and local control rate(LC) of all patients were 52%, 64%, and 75%, respectively. There was no significant difference between the "uaresected" and "resected" groups in OS, CSS, or LC. Local recurrence was observed in 12 patients. In the "resected" group, for local control, it was important to reduce viable tumor before maxillectomy. Preoperative > or = 60 Gy irradiation was considered to be effective to reduce tumor viability. CONCLUSION: There was no significant difference between the "unresected" and "resected" groups in OS, CSS, or LC. In the "resected" group, preoperative irradiation > or = 60 Gy was considered to be effective for local control. In radical treatment of maxillary sinus carcinoma, maxillectomy is not always necessary. Concurrent chemoradiation therapy with or without antrostomy is a reasonable treatment strategy.  相似文献   

16.
The purpose of our study was to determine the effect of tumor-targeted radiation in neuroblastoma by correlating administered (131)I-metaiodobenzylguanidine (MIBG) activity to tumor and whole-body dosimetry, tumor volume change, overall response, and hematologic toxicity. METHODS: Eligible patients had MIBG-positive lesions and tumor-free, cryopreserved hematopoietic stem cells. Activity was administered according to body weight and protocol as part of a phase I and phase II study. The whole-body radiation dose was derived from daily 1-m exposure measurements, the tumor self-absorbed radiation dose (TSARD) was determined from scintillation-camera conjugate views, and the tumor volume was measured using CT or MRI. RESULTS: Forty-two patients with refractory neuroblastoma (16 with prior hematopoietic stem cell transplant) received a median activity of 555 MBq/kg (15 mCi/kg) (range, 93-770 MBq/kg) and a median total activity of 11,470 MBq (310 mCi) (range, 3,330-30,969 MBq). The median whole-body radiation dose was 228 cGy (range, 57-650 cGy) and the median TSARD was 3,300 cGy (range, 312-30,500 cGy). Responses among evaluable patients included 16 partial response, 3 mixed response, 14 stable disease, and 9 progressive disease. Higher TSARD values predicted better overall disease response (P < 0.01). The median decrease in tumor volume was 19%; 18 tumors decreased, 4 remained stable, and 5 increased in size. Correlation was seen between administered activity per kilogram and whole-body dose as well as hematologic toxicity (assessed by blood platelet and neutrophil count nadir) (P < 0.05). The median whole-body dose was higher in the 11 patients who required hematopoietic stem cell infusion for prolonged neutropenia versus the 31 patients who did not (323 vs. 217 cGy; P = 0.03). CONCLUSION: Despite inaccuracies inherent in dosimetry methods, (131)I-MIBG activity per kilogram correlated with whole-body radiation dose and hematologic toxicity. The TSARD by conjugate planar imaging predicted tumor volume decrease and also correlated with overall tumor response.  相似文献   

17.
Campbell  OR; Amendola  BE; Brady  LW 《Radiology》1990,174(2):565-566
Recurrent pterygia in 42 patients (48 eyes) were treated locally with strontium-90 irradiation from May 1967 to May 1988. The 31 male patients had an average age of 52 years; the 11 female patients, 46 years. All patients underwent surgical resection of the recurrent pterygia with use of the bare-sclera technique. During the immediate postoperative period the surgical site was treated with an Sr-90 applicator (beta irradiation). Doses ranged from 10 to 70 Gy (average, 50 Gy). Follow-up times ranged from 8 to 136 months (median, 14 months). The local control rate was 89%. Four of the five recurrences were in patients treated with doses of 1,000-1,500 cGy (P less than .0002). None of the patients developed cataracts or any other serious complications.  相似文献   

18.
PURPOSE: To report results of a phase II trial of high-dose-rate intra-operative radiation therapy (HDR-IORT) for malignant pleural mesothelioma (MPM). METHODS AND MATERIALS: Seven patients had extrapleural pneumonectomy with IORT (EPP/IORT) and 6 patients had pleurectomy/decortication with IORT (PD/IORT) between 1994 and 1996. IORT was delivered with 192Ir using a customized applicator with a remote afterloader. A median of 3 sites were treated to a median area of 143 cm2. A dose of 1500 cGy was prescribed at each site, with 1000 cGy delivered to the mediastinum. Postoperative external beam radiation therapy (EBRT) was given 3-5 weeks later. Median follow-up was 8 months (range, 1-84 months). RESULTS: Five patients developed local failure. Two-year local control and survival rates were 35% and 23%, respectively. Mortality was 2/13 (15%), 1 from each surgical group. Serious complications requiring further intervention occurred in 3/6 (50%) of the EPP/IORT group and 1/5 (20%) of the PD/IORT group. CONCLUSIONS: HDR-IORT after EPP for MPM is prohibitively toxic and has been abandoned, while its use with PD remains in question.  相似文献   

19.
PurposeTo evaluate the safety and effectiveness of yttrium-90 (90Y) radioembolization as first-line treatment for unresectable intrahepatic cholangiocarcinoma (ICC).Materials and MethodsThis prospective study enrolled patients who had never received chemotherapy, liver embolization, and radiation therapy. The tumors were solitary in 16 patients, multiple in 8 patients, unilobar in 14 patients, and bilobar in 10 patients. Patients underwent transarterial radioembolization with 90Y-labeled glass microspheres. The primary end point was hepatic progression-free survival (HPFS). Secondary end points were overall survival (OS), tumor response, and toxicity.ResultsTwenty-four patients (age, 72.3 years ± 9.3; 12 women) were included in the study. The median delivered radiation dose was 135.5 Gy (interquartile range, 77.6 Gy). The median HPFS was 5.5 months (95% CI, 3.9–7.0 months). Analysis failed to identify any prognostic factor associated with HPFS. Imaging response at 3 months showed 56% disease control, and the best radiographic response was 71% disease control. The median OS from the radioembolization treatment was 19.4 months (95% CI, 5.0–33.7). Patients with solitary ICC had significantly longer median OS than patients with multifocal ICC: 25.9 months (95% CI, 20.8–31.0 months) versus 10.7 months (95% CI, 8.0–13.4 months) (P = .02). Patients with progression on the 3-month imaging follow-up had significantly shorter median OS than patients who had stable disease at 3 months: 10.7 months (95% CI, 0.7–20.7 months) versus 37.3 months (95% CI, 16.5–58.1 months) (P = .003). Two (8%) Grade 3 toxicities were reported.ConclusionsFirst-line treatment of ICC with radioembolization showed promising OS and minimal toxicity, especially in patients with solitary tumor. Radioembolization may be considered as a first-line treatment option for unresectable ICC.  相似文献   

20.
Treatment of leaks after endovascular repair of aortic aneurysms   总被引:7,自引:0,他引:7  
PURPOSE: To evaluate leaks after the endovascular repair of aortic aneurysms and treat them with occlusive therapy. MATERIALS AND METHODS: Seventy patients (11 women, 59 men), aged 26-82 years (mean, 69.2 years), underwent transfemoral insertion of endoluminal stent-grafts for treatment of aortic aneurysms. Indications were traumatic pseudoaneurysms (n = 5) or arteriosclerotic aneurysms (n = 65). Aneurysms were thoracic (n = 5) or infrarenal (n = 65). To exclude the possibility of leaks, spiral computed tomography (CT) was performed at 3-month intervals. Patients with leaks that persisted unchanged longer than 3 months were referred for angiography and occlusive therapy. RESULTS: At CT, 21 leaks were identified in 17 of 70 patients (24%). Only 11 of those 17 patients (65%) had leaks identified with conventional aortography. Selective angiography, however, depicted all of these. Eighteen of 21 leaks proved amenable to occlusive treatment: surgery (n = 1), further stent implantation (n = 4), or embolization (n = 13). In one leak, spontaneous occlusion occurred after 3 months. Two leaks in either the iliolumbar or the median sacral artery were inaccessible; one remained untreated, and the other was unsuccessfully treated. Mean follow-up of occlusive therapy was 6.8 months (range, 2-14 months). CONCLUSION: Successful occlusion of perigraft leaks is feasible in most cases and can be performed without major complications.  相似文献   

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