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1.
We previously described delayed pressor response (DPR) 3 h after endothelin (ET)-1 injection in normotensive rats. In the current study, we examined effects of the ETA receptor antagonist BQ123 (0.01 mumol/kg/min intravenously, i.v.), phosphoramidon (100 mumol/kg i.v.), the neutral endopeptidase inhibitor SQ28603 (112 mumol/kg + 0.04 mumol/kg/min i.v.), the angiotensin-converting enzyme inhibitor enalaprilat (10 mumol/kg i.v.), and the thromboxane receptor antagonist, SQ29548 (0.5 mumol/kg + 0.5 mumol/kg/h i.v.) on DPR. Vehicle and ET-1 (1.0 nmol/kg i.v.) were administered on day 1; vehicle or drug and ET-1 were administered on day 2. BQ123 inhibited DPR 36% (vehicle 44 +/- 5, BQ123 28 +/- 3 mm Hg); phosphoramidon inhibited DPR 56% (vehicle 45 +/- 4, and phosphoramidon 20 +/- 5 mm Hg). DPR was unchanged after SQ28603 (vehicle 39 +/- 2 and SQ28603 44 +/- 2 mm Hg), enalaprilat (vehicle 39 +/- 2 and enalaprilat 38 +/- 7 mm Hg), or SQ29548 (vehicle 46 +/- 6 and SQ29548 43 +/- 3 mm Hg). The results suggest that DPR 3 h after ET-1 injection in rats is mediated in part through ETA receptors. DPR does not appear to involve thromboxane or synthesis of angiotensin II (AII), but may be related to synthesis of ET-1.  相似文献   

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PURPOSE: To examine the effect of treatment using Bromodeoxyuridine (BrdU) during radiation therapy on malignant glioma patient survival by comparing historical survival data from several large clinical trials. METHODS: A retrospective analysis of patient data from Radiation Therapy Oncology Group (RTOG) trials 74-01, 79-18, and 83-02 and the Northern California Oncology Group (NCOG) study 6G-82-1 was conducted. Patient data was supplied by both groups, and analyzed by the RTOG. Pretreatment characteristics including age, extent of surgery, Karnofsky Performance Status (KPS), and histopathology were collected; the only treatment variable evaluated was the use of BrdU during radiation therapy. Radiation dose, dose-fractionation schedule, use of chemotherapy, and/or type of chemotherapy was not controlled for in the analyses. Univariate and multivariate analyses were conducted to examine the potential treatment effect of BrdU on patient survival. RESULTS: Data from 334 patients treated with BrdU on NCOG 6G-82-1 and 1743 patients treated without BrdU on 3 RTOG studies was received. Patients were excluded from the review if confirmation of eligibility could not be obtained, if the patient was ineligible for the study they entered, if central pathology review was not done, or if radiotherapy data was not available. Patients treated according to the RTOG studies had to start radiotherapy within 4 weeks of surgery; no such restriction existed for the NCOG studies. To ensure comparability between the studies, patients from the NCOG studies who began treatment longer than 40 days from surgery were also excluded. The final data set included 296 cases from the NCOG studies (89%) and 1478 cases from the RTOG studies (85%). For patients with glioblastoma multiforme (GBM) the median survival was 9.8 months in the RTOG studies and 13.0 months in the NCOG trial (p < 0.0001). For patients with AA the median survival was 35.1 months for the RTOG studies and 42.8 months in the NCOG trial (p = 0.126). Univariate results showed consistent results favoring BrdU among patients over 30 years of age, across the extent of surgery, and for GBM patients. A proportional hazards regression model that included treatment, histopathology, KPS, age, and extent of surgery demonstrated that treatment with BrdU was included in the best model only for the GBM group of patients (risk ratio 0.83). CONCLUSIONS: Because of the heterogeneity of the treatment groups, including potentially important differences in pathology reviewers assessment of nonglioblastoma cases, differences in radiation dose and schedules, and chemotherapy during or after radiation, these analyses cannot provide the definitive answer as to whether BrdU given during radiation therapy improves survival in patients with malignant glioma. There does appear to be a favorable treatment effect seen in patients with GBM, with a lesser effect in patients with AA.  相似文献   

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BACKGROUND: Regionally advanced, surgically unresectable non-small-cell lung cancer represents a disease with an extremely poor prognosis. External-beam irradiation to the primary tumor and regional lymphatics is generally accepted as standard therapy. The use of more aggressive radiation regimens and the addition of cytotoxic chemotherapy to radiotherapy have yielded conflicting results. Recently, however, results from clinical trials using innovative irradiation delivery techniques or chemotherapy before irradiation have indicated that patients treated with protocols that incorporate these modifications may have higher survival rates than patients receiving standard radiation therapy. PURPOSE: On the basis of these results, the Radiation Therapy Oncology Group (RTOG)-Eastern Cooperative Oncology Group (ECOG) elected to conduct a phase III trial comparing the following regimens: 1) standard radiation therapy, 2) induction chemotherapy followed by standard radiation therapy, and 3) twice-daily radiation therapy. METHODS: Patients with surgically unresectable stage II, IIIA, or IIIB non-small-cell lung cancer were potential candidates. Staging was nonsurgical. Patients were required to have a Karnofsky performance status of 70 or more and weight loss less than 5% for 3 months prior to entry into the trial, to be older than 18 years of age, and to have no metastatic disease. Of the 490 patients registered in the trial, 452 were eligible. The disease in 95% of the patients was stage IIIA or IIIB. More than two thirds of the patients had a Karnofsky performance status of more than 80. Patients were randomly assigned to receive either 60 Gy of radiation therapy delivered at 2 Gy per fraction, 5 days a week, over a 6-week period (standard radiation therapy); induction chemotherapy consisting of cisplatin (100 mg/m2) on days 1 and 29 and 5 mg/m2 vinblastine per week for 5 consecutive weeks beginning on day 1 with cisplatin, followed by standard radiation therapy starting on day 50; or 69.6 Gy delivered at 1.2 Gy per fraction twice daily (hyperfractionated radiation therapy). RESULTS: Toxicity was acceptable, with four treatment-related deaths. Three patients subsequently died of chronic pulmonary complications. Compliance with protocol treatment was acceptable. One-year survival (%) and median survival (months) were as follows: standard radiation therapy--46%, 11.4 months; chemotherapy plus radiotherapy--60%, 13.8 months; and hyperfractionated radiation therapy--51%, 12.3 months. The chemotherapy plus radiotherapy arm was statistically superior to the other two treatment arms (logrank P = .03). CONCLUSIONS: In "good-risk" patients with surgically unresectable non-small-cell lung cancer, induction chemotherapy followed by irradiation was superior to hyperfractionated radiation therapy or standard radiation therapy alone, yielding a statistically significant short-term survival advantage.  相似文献   

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PURPOSE: To assess the efficacy of neoadjuvant methotrexate, cisplatin, and vinblastine (MCV) chemotherapy in patients with muscle-invading bladder cancer treated with selective bladder preservation. PATIENTS AND METHODS: One hundred twenty-three eligible patients with tumor, node, metastasis system clinical stage T2 to T4aNXMO bladder cancer were randomized to receive (arm 1, n=61 ) two cycles of MCV before 39.6-Gy pelvic irradiation with concurrent cisplatin 100 mg/m2 for two courses 3 weeks apart. Patients assigned to arm 2 (n=62) did not receive MCV before concurrent cisplatin and radiation therapy. Tumor response was scored as a clinical complete response (CR) when the cystoscopic tumor-site biopsy and urine cytology results were negative. The CR patients were treated with an additional 25.2 Gy to a total of 64.8 Gy and one additional dose of cisplatin. Those with less than a CR underwent cystectomy. The median follow-up of all patients who survived is 60 months. RESULTS: Seventy-four percent of the patients completed the protocol with, at most, minor deviations; 67% on arm 1 and 81% on arm 2. The actuarial 5-year overall survival rate was 49%; 48% in arm 1 and 49% in arm 2. Thirty-five percent of the patients had evidence of distant metastases at 5 years; 33% in arm 1 and 39% in arm 2. The 5-year survival rate with a functioning bladder was 38%, 36% in arm 1 and 40% in arm 2. None of these differences are statistically significant. CONCLUSION: Two cycles of MCV neoadjuvant chemotherapy were not shown to increase the rate of CR over that achieved with our standard induction therapy or to increase freedom from metastatic disease. There was no impact on 5-year overall survival.  相似文献   

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PURPOSE: To evaluate the effect of immediate androgen suppression in conjunction with standard external beam irradiation vs. radiation alone on a group of pathologically staged lymph node-positive patients with adenocarcinoma of the prostate. METHODS AND MATERIALS: A national prospective randomized trial (RTOG 85-31) of standard external beam irradiation plus immediate androgen suppression vs. external beam irradiation alone was initiated in 1985 for patients with locally advanced adenocarcinoma of the prostate. One hundred seventy-three of the patients in this trial had biopsy-proven pathologically involved lymph nodes. Ninety-eight of these patients received radiation plus the immediate androgen suppression (LHRH agonist), while 75 received radiation alone with hormonal manipulation instituted at the time of relapse. RESULTS: With a median followup of 4.9 years, estimated progression-free survival with PSA < 1.5 ng/ml at 5 years was 55% for the patients who received radiation plus immediate LHRH agonist vs. 11% of the patients who received radiation alone with hormonal manipulation at relapse (p = 0.0001). Because all of these patients had locally advanced disease (i.e., pathologically positive lymph nodes), stage does not explain this difference in outcome, and Gleason grade was not statistically different between the two groups. Estimated absolute survival at 5 years for the radiation and LHRH group was 73 vs. 65% for the radiation alone group who received androgen suppression at relapse. Estimated disease-specific survival at 5 years was 82% for the radiation and immediate LHRH agonist group and 77% for the radiation-alone group. CONCLUSION: Patients with adenocarcinoma of the prostate and pathologically involved pelvic lymph nodes (pN+ or clinical stage D1) should be seriously considered for external beam irradiation plus immediate hormonal manipulation over radiation alone with hormonal manipulation at the time of relapse.  相似文献   

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PURPOSE: To analyze disease failure patterns by pretreatment characteristics and treatment groups in a prospective randomized trial. METHODS AND MATERIALS: Patients with medically inoperable Stage II, unresectable IIIA and IIIB nonsmall cell lung cancer with KPS > or =70 and weight loss < or =5% were randomized to one of three treatment groups: standard radiation therapy with 60 Gy at 2.0 Gy per day (STD RT), induction chemotherapy with cisplatin 100 mg/m2 days 1 and 29 with vinblastine 5 mg/m2 weekly for 5 weeks followed by 60 Gy at 2.0 Gy per day (CT + RT), or hyperfractionated radiation therapy with 69.6 Gy at 1.2 Gy b.i.d. (HFX RT). Of 490 patients enrolled, 458 were evaluable. Minimum and median periods of observation for this analysis were 4 years and 6 years, respectively. RESULTS: Pretreatment characteristics were equally distributed. Toxicities were previously reported. Median survival rates were 11.4, 13.6, and 12.3 months for STD RT, CT + RT, and HFX RT, respectively (log rank p = 0.05, Wilcoxon p = 0.04). Survivals were 20, 31, and 24% at 2 years, and 4, 11, and 9% at 4 years in the STD RT, CT + RT, and HFX RT groups, respectively. There were no differences in local tumor control rates among the treatments. Patterns of first failure showed less distant metastasis (DM) (other than brain) for CT + RT compared to the RT alone arms (p = 0.04). Within squamous cell carcinoma (SCC), DM (other than brain) rates were 43%, 16%, and 38% in SCC for STD RT, CT + RT, and HFX RT, respectively (p = 0.0015). Patients with peripheral/chest wall lesions were significantly more likely to fail first in the thorax when treated on STD RT compared to CT + RT and HFX RT (p = 0.009). Survival rates were similar among the treatment arms for patients with squamous cell carcinoma. Among patients with nonsquamous cell carcinoma, failure patterns did not differ by treatment group, but survival was significantly better in those who were treated by induction chemotherapy (p = 0.04). CONCLUSION: Patients with squamous cell carcinoma treated on the CT + RT arm had a significant reduction of first DM other than brain, but there was difference in survival. Survival favored CT + RT in nonsquamous carcinoma despite similar failure patterns. Reasons for improved survival with CT + RT in NSCLC are not yet available.  相似文献   

8.
PURPOSE: To determine the response rate and survival of chemotherapy-naive patients with extensive-stage small-cell lung cancer (SCLC) treated with topotecan, and to determine the relationship of topotecan pharmacokinetics with response and toxicity. PATIENTS AND METHODS: Forty-eight patients with previously untreated, extensive-stage SCLC received 2.0 mg/m2 of topotecan daily for 5 days. The first 13 patients were treated without colony-stimulating factor (CSF) support; the next 35 patients received 5 micrograms/kg of granulocyte-colony-stimulating factor (G-CSF) for 10 to 14 days starting on day 6. Cycles were repeated every 3 weeks for a maximum of four cycles. Patients who had a partial response to topotecan after four cycles, stable disease after two cycles, or progressive disease at any time received salvage chemotherapy with cisplatin and etoposide. Topotecan pharmacokinetics were measured using a four-point sampling scheme. RESULTS: Of 48 patients, none had a complete response and 19 had a partial response, for an objective response rate of 39% (95% confidence interval [CI], 25.2% to 53.0%). The median response duration was 4.8 months (95% CI, 3.0 to 7.3). After a median follow-up duration of 18.2 months, the overall median survival time was 10.0 months (95% CI, 8.2 to 12.7); the 1-year survival rate was 39% (95% CI, 25.2% to 53.0%). Eight of 34 patients (24%) who received salvage chemotherapy responded. Four of 17 patients who did not respond to first-line therapy with topotecan responded to cisplatin and etoposide. The most common toxicity was hematologic. Ninety-two percent of patients treated without G-CSF developed grade 3 or 4 neutropenia, compared with 29% who received G-CSF. However, the incidence of neutropenic fevers was similar between the two groups (8% and 11%, respectively), and one patient in each group died of neutropenic fevers. There were no differences in objective tumor response, duration of response, time to treatment failure, or survival between the 13 patients who entered the study before G-CSF administration was mandated and the 35 patients who entered after and received G-CSF. There was poor correlation between the WBC count and absolute neutrophil counts (ANCs) and both the area under the curve (AUC) and maximum concentration++ (Cmx) of total topotecan in plasma. There was no correlation between the tumor response and either AUC or Cmx of total topotecan. CONCLUSION: The activity of topotecan in extensive-stage SCLC noted in this study warrants further investigation of this agent in phase III clinical trials.  相似文献   

9.
BACKGROUND: A number of single agents have been tested in patients with carcinoma of the head and neck receiving palliative treatment. In general, 15-30% of patients achieve a partial response lasting 3-4 months. Treatment has not been shown to alter survival rates. It is clear that new drugs with potentially greater activity need to be identified. For this purpose, the Eastern Cooperative Oncology Group conducted a Phase II evaluation of paclitaxel. METHODS: Patients with recurrent, metastatic, or locally advanced, incurable squamous cell carcinoma of the head and neck were eligible. The dose and schedule tested was the maximum tolerable dose of 250 mg/m2 determined from Phase I trials using a 24-hour infusion schedule and granulocyte-colony stimulating factor support. Courses were given at 3-week intervals until progression of disease was documented. Dose modifications were specified for hematologic toxicity and for neurotoxicity. RESULTS: Thirty-four patients were registered on study and 30 were eligible. Severe or life-threatening granulocytopenia was the most frequent toxicity observed, occurring in 91% of patients. Prior to response evaluation, one patient died of sepsis and one died of a myocardial infarct. Response was observed in 40% of eligible patients (4 complete and 8 partial responses). The median duration of response was 4.5 months (range, 2-20 months), with a median survival of 9.2 months and a 1-year survival rate of 33%. CONCLUSIONS: These results indicate that paclitaxel is an active agent for the treatment of squamous cell carcinoma of the head and neck. Studies evaluating alternative infusion schedules and combination regimens currently are underway.  相似文献   

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PURPOSE: Pancreatic cancer is difficult to treat, with most patients surgically unresectable at the time of diagnosis. Radiotherapy and chemotherapy can offer palliation, but more effective therapy is needed. This trial evaluated the effects of an aggressive schedule of paclitaxel given with granulocyte colony-stimulating factor (G-CSF) to patients with advanced pancreatic cancer. PATIENTS AND METHODS: All patients were required to have a histologic diagnosis of pancreatic adenocarcinoma with measurable disease and no prior chemotherapy or radiation therapy. Patients had to have performance status of 0 to 2, pretreatment absolute granulocyte count > or = 1,500/microL, and platelet count greater than or equal to the institutional lower limit of normal. Following pretreatment with dexamethasone, diphenhydramine, and cimetidine, patients received paclitaxel at a dose of 250 mg/m2 by 24-hour infusion on day 1, repeated every 21 days. G-CSF was given at a dose of 5 microg/kg/d on days 3 to 18 or until two consecutive absolute neutrophil counts (ANCs) > or = 10,000/microL were obtained. Doses of paclitaxel were modified depending on nadir counts. RESULTS: Forty-five patients were entered onto this study, with six ineligible. For the 39 eligible patients, there was one complete response (CR) and two partial responses (PRs), five stable/no responses, 23 increasing disease, two early deaths, and six patients whose assessment was inadequate to determine response. The response rate was therefore three of 39 or 8% (95% confidence interval [CI], 2% to 21%). The median survival time for the 39 eligible patients was 5 months. The most common toxicities were anemia, leukopenia/granulocytopenia, malaise/fatigue, nausea/vomiting, alopecia, thrombocytopenia, paresthesias, and liver function abnormalities. There was one death due to sepsis. CONCLUSION: Single-agent paclitaxel in this dose and schedule has minimal activity in pancreatic adenocarcinoma patients.  相似文献   

13.
Locally produced proinflammatory cytokines are likely to play a pathophysiological role in autoimmune thyroid disease. An important feature of the thyroid, not previously considered in cytokine actions, is the barrier created by the follicular epithelium, which secludes two lumenal autoantigens [thyroglobulin (Tg) and thyroperoxidase] from the extrafollicular space. We examined the influence of recombinant cytokines on the barrier function of human thyrocytes cultured as a tight and polarized monolayer in bicameral chambers. Whereas interleukin (IL)-6 (100 U/mL), interferon-gamma (100 U/mL), tumor necrosis factor-alpha (10 ng/mL), and transforming growth factor-beta1 (10 ng/mL) had no effects, exposure to IL-1alpha for 24-48 h reduced the transepithelial resistance from >1000 to <50 omega x cm2 and increased the paracellular flux of [3H]inulin and exogenous 125I-Tg. This response to IL-1alpha, which was dose dependent (1-1000 U/mL) and reversible, was accompanied by dramatic morphological changes of the epithelial junction complex, including aberrant localization of the tight junction protein zonula occludens-1. At the same time, IL-1alpha decreased the apical secretion of endogenous Tg and stimulated the basolateral release of a novel high-molecular-mass protein. We conclude that IL-1alpha reduces the thyroid epithelial barrier without signs of general cytotoxicity. The observation suggests a mechanism by which IL-1alpha may promote the exposure of hidden autoantigens to the immune system in thyroid autoimmunity.  相似文献   

14.
Recommendations of the American Association of Physicists in Medicine (AAPM) for the practice of brachytherapy physics are presented. These guidelines were prepared by a task group of the AAPM Radiation Therapy Committee and have been reviewed and approved by the AAPM Science Council.  相似文献   

15.
Vasa previa is presented when fetal vessels cross the internal os as a velamentous insertion of the umbilical cord. This retrospective study is to review the diagnosis, the management, and the outcome of this condition over the 10 years period in Ramathibodi Hospital, Bangkok, Thailand. Five cases were diagnosed after the rupture of membranes with only one case diagnosed prior to the rupture of membranes. The fetal mortality was 50 per cent. Despite continued advances in diagnostic procedures, vasa previa still presents considerable risk to the fetus.  相似文献   

16.
PURPOSE: Previous studies have demonstrated a beneficial effect of intraperitoneally applied mitomycin bound to activated carbon particles (M-CH) in preventing intraabdominal recurrence following curative surgery for gastric cancer. The Austrian Working Group for Stomach Cancer, a subgroup of the Austrian Working Group for Surgical Oncology, initiated a multicentric phase III trial to evaluate the safety and efficacy of this treatment regimen. PATIENTS AND METHODS: A total of 91 patients with a radically resected gastric cancer infiltrating the serosal surface were randomly assigned to receive either 50 mg mitomycin bound to a solution of 375 mg carbo adsorbens intraperitoneally before closure of the abdominal wound (n = 46) or served as a surgical control group (n = 45). Postoperative complications and recurrence-free and overall survival were evaluated to analyze the risks and benefits of this treatment. RESULTS: After a median observation period of 597 days (range, 72 to 1,096), a significantly higher postoperative complication rate was observed in the M-CH group (35%) compared with the control group (16%) (P < .02). In accordance with this finding, the postoperative (60 days) mortality rate was also significantly elevated in the M-CH group (11% v 2% in the control group). Since analysis of overall and recurrence-free survival failed to show any beneficial effect of M-CH therapy, the protocol committee decided to stop further recruitment of patients onto this study. CONCLUSION: Adjuvant intraperitoneal therapy of gastric cancer by mitomycin bound to activated carbon particles is associated with an increased rate of postoperative complications. However, no benefit for prognosis following radical resection of locally advanced tumors was observed in this multicenter phase III trial.  相似文献   

17.
A decline of cytosol protein kinase C activity was observed in rat myocardial cells at 4 and 8 h after endotoxin administration, and membrane-associated protein kinase C activity rose at the same time. The activity of membrane protein kinase C in aortic smooth muscle cells at 0.5 and 4 h after endotoxin injection was higher than that in control, while cytosol protein kinase C activity was lower. The results indicate that protein kinase C was activated in myocardial cells and aortic smooth muscle cells during various phases of endotoxemia.  相似文献   

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A new regimen not cross-resistant with standard regimens was developed for patients with relapsed or refractory Hodgkin's disease and non-Hodgkin's lymphoma. The regimen consisted of cisplatin, 70 mg/M2 given intravenously on day 1, vindesine, 3 mg/M2 given intravenously on days 1 and 8 (and also on day 15 of the first cycle only), and methylguazone, 600 mg/M2 given intravenously on days 8 and 15. Courses were repeated every 21 days. Thirty-nine patients (35 with non-Hodgkin's and 4 with Hodgkin's lymphoma) were treated and all were evaluable for response and toxicity. There were 5 complete and 14 partial responses for a total response rate of 49% (C.I. = 35%-63%). The median durations of partial and complete response were only 2.8 and 4.2 months, respectively. Only one patient remained in complete response for more than a year. There was one treatment-related death from renal failure on the study. Although this regimen was, in general. well tolerated the results are disappointing and seem no better than those obtained with many other salvage regimens for lymphoma.  相似文献   

20.
To determine whether the charybdotoxin-sensitive subtypes of voltage-gated K+ channels (Kv1.2 and Kv1.3) exist in inhibitory pre-synaptic terminals, effects of K+ channel blockers including TEA, charybdotoxin (ChTX), iberiotoxin (IbTX), kaliotoxin (KTX) and margatoxin (MgTX) on the inhibitory transmission were examined with cultured rat hippocampal neurons. Monosynaptic inhibitory postsynaptic currents (IPSCs) evoked by electrical stimulation of single presynaptic neurons were recorded from the whole-cell clamped postsynaptic neurons. In the presence of TEA, application of ChTX greatly increased the amplitude of IPSCs. A specific maxi-K+ channel blocker IbTX failed to augment IPSCs. KTX and MgTX, both of which block Kv1.3 but not Kv1.2, mimicked the facilitating effect of ChTX. In the absence of TEA, application of ChTX increased the IPSC amplitude significantly, while IbTX was without effect. These results indicate that the ChTX-sensitive subtypes of voltage-gated K+ channels, most likely Kv1.3, contribute to the repolarization of action potentials at presynaptic terminals of hippocampal inhibitory neurons, and that the ChTX-induced facilitation of the transmission can be explained by its effects on the Kv channels rather than maxi-K+ channels.  相似文献   

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