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961.
While significant progress has been made in understanding the induction of tumor vasculature by secreted angiogenic factors, little is known regarding contact-dependent signals that promote tumor angiogenesis. Here, we report that the Notch ligand Jagged1 induced by growth factors via mitogen-activating protein kinase (MAPK) in head and neck squamous cell carcinoma (HNSCC) cells triggered Notch activation in neighboring endothelial cells (ECs) and promoted capillary-like sprout formation. Jagged1-expressing HNSCC cells significantly enhanced neovascularization and tumor growth in vivo. Moreover, the level of Jagged1 was significantly correlated with tumor blood vessel content and associated with HNSCC development. Our results elucidate a novel mechanism by which the direct interplay between tumor cells and ECs promotes angiogenesis through MAPK and Notch signaling pathways.  相似文献   
962.
963.
Population-based studies may give results different from randomized clinical trials assessing the efficacy of antibiotics.OBJECTIVE: To determine the effectiveness of amoxicillin, azithromycin, cefprozil and clarithromycin in the treatment of acute otitis media (AOM) in children. METHODS: Using Quebec Health Insurance databases (RAMQ), we selected a cohort of children aged < or = 6 years, with a first episode of AOM between 1999 and 2002. The index AOM was defined as a medical service claim with a diagnosis of AOM and an antibiotic dispensation in the following 72 hours. Failures were defined as a new antibiotic dispensation, a hospitalization or outpatient visit for complications related to AOM in the 30 days after the index AOM. Data were analyzed using logistic regression. RESULTS: Overall, 12,693 failures occurred among 60,513 first episodes of AOM. Azithromycin was the only antibiotic that was associated with a decreased risk of failure overall, when compared to amoxicillin (OR 0.88, 95% CI: 0.82, 0.94). However in the first 3 days of treatment (n = 680), azithromycin was more associated with treatment failure (OR 1.6, 95% CI: 1.3, 2.0). Compared to amoxicillin, post-therapy failures (n = 9387) were more likely to occur with cefprozil (OR 1.2, 95%CI: 1.2, 1.3) but were less with azithromycin (OR 0.8 95% CI: 0.8, 0.9). CONCLUSIONS: Azithromycin had the lowest risk of failure 30 days after the onset of treatment but an increased risk of failure during the first few days of treatment. Amoxicillin remains an effective first-line drug for treating first AOM episodes.  相似文献   
964.
The study of mitotic transduction of the signal showed that overexpression of pAkt and reduction in pERK expression would be associated a biological relapse. For tumors T1-3 N0M0 at the high risk of local relapse after prostatectomy, an immediate radiotherapy compared with a differed radiotherapy (at the time of PSA relapse), showed a significant reduction in the rate of local relapse and an ameliorated progression free survival. The effectiveness of the docetaxel was confirmed in two phase III randomized clinical trials : TAX-327 with 3 arms compared docetaxel every 21 days, docetaxel every 7 days and mitoxantrone. All arms were prednisone-based. An increase in overall survival, PSA progression free survival, PSA response rate and a pain reduction were highlighted in the docetaxel arm every 21 days. Docetaxel obtained at the end of this study the marketing authorization in this indication and became the treatment of reference. The SWOG 99-16 study compared the docetaxel estramustine association with the same arm of reference, mitoxantrone and prednisone, with similar results. The addition of estramustine to the docetaxel seems to improve the PSA response rate and progression free survival, but with a greater embolic toxicity. The addition of an antiangiogenic agent, the thalidomide, to docetaxel, improves progression free survival and overall survival. PSA responses were observed with an inhibitor of the proteasome, the bortezomib, in monotherapy, contrary to the imatinib which in monotherapy didn't have any effectiveness. Studies in association with docetaxel are ongoing. Some biological responses were observed with a vaccine anti MUC-1 and must be confirmed on a greater series of patients. The docetaxel impact on localized disease is actually evaluated.  相似文献   
965.
BACKGROUND: Although patients with cancer are often accompanied by a relative during medical interviews, to the authors' knowledge little is known regarding the efficacy of communication skills training programs on physicians' communication skills in this context. The objective of the current study was to assess the efficacy of 6 consolidation workshops, 3 hours in length, that were conducted after a 2.5-day basic training program. METHODS: After attending the basic training program, physicians were assigned randomly to consolidation workshops or to a waiting list. Training efficacy was assessed through simulated and actual interviews that were recorded on an audio tape at baseline, after consolidation workshops for the consolidation-workshops group, and 5 months after the end of basic training for the waiting-list group. Communication skills were assessed according to the Cancer Research Campaign Workshop Evaluation Manual. Patients' and relatives' perceptions of and satisfaction with physicians' communication performance were assessed using a 15-item questionnaire. RESULTS: Sixty-two physicians completed the training program. Compared with physicians who participated to the basic training program, when addressing the patient, physicians who were randomized to the consolidation workshops used more open, open directive, and screening questions (P = 0.011 in simulated patient interviews and P = 0.005 in actual patient interviews) and elicited and clarified psychologic concerns more often (P = 0.006 in simulated patient interviews and P < 0.001 in actual patient interviews). When they addressed the relative, physicians who were randomized to the consolidation workshops gave less premature information (P = 0.032 in simulated patient interviews and P < 0.001 in actual patient interviews). When they addressed the patient and the relative simultaneously, physicians who were randomized to the consolidation workshops used more empathy, educated guesses, alerting to reality, confronting, negotiating, and summarizing (P = 0.003 in simulated patient interviews and P = 0.024 in actual patient interviews). Patients, but not relatives, who interacted with physicians in the consolidation-workshops group were more satisfied globally with the interviews (P = 0.022). CONCLUSIONS: Six 3-hour consolidation workshops resulted in improved communication skills addressed to patients and to relatives. The current results showed that the transfer of skills addressing relatives' concerns remained limited and that consolidation workshops should focus even more systematically on the practice of three-person interviews.  相似文献   
966.
BACKGROUND: No study to date has assessed the impact of skills acquisition after a communication skills training program on physicians' ability to detect distress in patients with cancer. METHODS: First, the authors used a randomized design to assess the impact, on physicians' ability to detect patients' distress, of a 1-hour theoretical information course followed by 2 communication skills training programs: a 2.5-day basic training program and the same training program consolidated by 6 3-hour consolidation workshops. Then, contextual, patient, and communication variables or factors associated with physicians' detection of patients' distress were investigated. After they attended the basic communication skills training program, physicians were assigned randomly to consolidation workshops or to a waiting list. Interviews with a cancer patient were recorded before training, after consolidation workshops for the group that attended consolidation workshops, and approximately 5 months after basic training for the group that attended basic training without the consolidation workshops. Patient distress was recorded with the Hospital Anxiety and Depression Scale before the interviews. Physicians rated their patients' distress on a visual analog scale after the interviews. Physicians' ability to detect patients' distress was measured through computing differences between physicians' ratings of patients' distress and patients' self-reported distress. Communication skills were analyzed according to the Cancer Research Campaign Workshop Evaluation Manual. RESULTS: Fifty-eight physicians were evaluable. Repeated-measures analysis of variance showed no statistically significant changes over time and between groups in physicians' ability to assess patient distress. Mixed-effects modeling showed that physicians' detection of patients' distress was associated negatively with patients' educational level (P = 0.042) and with patients' self-reported distress (P < 0.000). Mixed-effects modeling also showed that physicians' detection of patient distress was associated positively with physicians breaking bad news (P = 0.022) and using assessment skills (P = 0.015) and supportive skills (P = 0.045). CONCLUSIONS: Contrary to what was expected, no change was observed in physicians' ability to detect distress in patients with cancer after a communication skills training programs, regardless of whether physicians attended the basic training program or the basic training program followed by the consolidation workshops. The results indicated a need for further improvements in physicians' detection skills through specific training modules, including theoretical information about factors that interfere with physicians' detection and through role-playing exercises that focus on assessment and supportive skills that facilitate detection.  相似文献   
967.
BACKGROUND: Sarcomas are a rare complication of radiotherapy for breast carcinoma and patients have a poor prognosis. The incidence, histology, and management of patients with sarcomas were reviewed in the current study. METHODS: The authors reviewed the records of 16,705 patients with breast carcinoma. Of these, 13,472 (81%) were treated with megavoltage radiotherapy and 3233 were treated without at the Institute Curie (Paris, France) between 1981 and 1997. Median doses of 50-55 grays (Gy) in 25-27 fractions were delivered to the whole breast over a period of 5-5.5 weeks (2 Gy/day, 5 weekly fractions) followed, when indicated, by a 16-26-Gy boost to the tumor or tumor bed. Treatment of radiation-induced sarcomas (RIS) consisted mostly of radical surgery and chemotherapy. RESULTS: Overall, 35 patients developed sarcomas. Of these, 27 fulfilled the Cahan criteria. The median follow-up was 9.3 years (range, 1-22.4 years). The latency period ranged from 3 years to 20.3 years. Thirteen sarcomas were located in the breast, 5- in the chest wall, 3 in the sternum, 2 in the supraclavicle, 1 in the scapula, and 3 in the axilla. Histologic evaluation identified 13 angiosarcomas, 3 osteosarcomas, 5 undifferentiated sarcomas, 1 malignant fibrous histiocytoma, 2 leiomyosarcomas, 1 fibrosarcoma, 1 rhabdomyosarcoma, and 1 myosarcoma. The cumulative RIS incidence was 0.07% (+/- 0.02) at 5 years, 0.27% (+/- 0.05) at 10 years, and 0.48% (+/- 0.11) at 15 years. Standardized incidence ratios were 10.2 (95% confidence interval, 9.03-11.59) for irradiated patients and 1.3 (0.3-3.6) for nonirradiated patients. Of the 27 patients, 15 died of sarcoma within 1 month to 14.5 years (mean, 34.2 +/- 0.7 months). The 5-year actuarial survival rate after diagnosis of RIS was 36% (+/- 0.11). CONCLUSIONS: The current study confirmed the rarity of RIS. However, it showed that the risk increased with time. Therefore, careful, long-term follow-up of patients treated with radiotherapy is needed for early detection and efficacious treatment of these malignancies.  相似文献   
968.
YaDeau JT  Liguori GA  Zayas VM 《Anesthesia and analgesia》2005,101(3):661-5, table of contents
We prospectively evaluated 1273 patients who received spinal (or combined spinal-epidural [CSE]) anesthesia with 1.5% mepivacaine (plain, no glucose) for ambulatory surgery. We hypothesized that analysis of a large series of patients would confirm previous findings that isobaric 1.5% mepivacaine is not frequently associated with transient neurologic symptoms (TNS). Patients were contacted twice after the anesthetic, at days 1-4 and days 6-9. One-thousand-two-hundred-ten patients were successfully contacted postoperatively (95% follow-up rate). None of the patients had permanent neurologic sequelae from the anesthetic. None of the 372 CSE anesthetics was inadequate for surgery. Fourteen of 838 (1.7%) of the spinal anesthetics were inadequate. TNS, defined as the new onset of back pain that radiated bilaterally to buttocks or distally, occurred in 78 patients (6.4%; 95% confidence intervals 5.1%-8%). The mean age of patients who developed TNS (48 +/- 14 yr) was older than that of patients without TNS (41 +/- 16 yr) (P < 0.001). TNS was not influenced by gender or intraoperative position. The frequent success rate and infrequent rates of complications such as TNS and postdural puncture headache suggest that spinal anesthesia with mepivacaine is likely to be a safe and effective anesthetic for ambulatory patients.  相似文献   
969.
Balzan S  Belghiti J  Farges O  Ogata S  Sauvanet A  Delefosse D  Durand F 《Annals of surgery》2005,242(6):824-8, discussion 828-9
OBJECTIVE: To standardize the definition of postoperative liver failure (PLF) for prediction of early mortality after hepatectomy. SUMMARY BACKGROUND DATA: The definition of PLF is not standardized, making the comparison of innovations in surgical techniques and the timely use of specific therapeutic interventions complex. METHODS: Between 1998 and 2002, 775 elective liver resections, including 69% for malignancies and 60% major resections, were included in a prospective database. The nontumorous liver was abnormal in 43% with steatosis >30% in 14%, noncirrhotic fibrosis in 43%, and cirrhosis in 12%. The impact of prothrombin time (PT) <50% and serum bilirubin (SB) >50 micromol/L on postoperative days (POD) 1, 3, 5, and 7 was analyzed. RESULTS: The lowest PT level was observed on postoperative day (POD) 1, while the peak of SB was observed on POD 3. These 2 variables tended to return to preoperative values by POD 5. The median interval between hepatectomy and postoperative death was 15 days (range, 5-39 days). Postoperative mortality significantly increased in patients with PT <50% and SB >50 microml/L. The conjunction of PT <50% and SB >50 micromol/L on POD 5 was a strong predictive factor of mortality. In patients with significant morbidity, this "50-50 criteria" was met 3 to 8 days before clinical evidence of complications. CONCLUSIONS: The association of PT <50% and SB >50 microml/L on POD 5 (the 50-50 criteria) was a simple, early, and accurate predictor of more than 50% mortality rate after hepatectomy. This criteria could be identified early enough, before clinical evidence of complications, for specific interventions to be applied in due time.  相似文献   
970.
Repeat hepatectomy for colorectal liver metastases   总被引:1,自引:0,他引:1  
This study includes 16 patients (9 men, 7 women; mean age 64 years) who underwent a total of 19 repeat hepatectomies for metastasis after colon (n=7) or rectal (n=9) carcinoma. All patients were reoperated for recurrent liver metastasis after the first resection (mean, 21 months; range, 7-40 months), and three had a third hepatectomy 13, 24, or 65 months after the second. Perioperative mortality was 0% and morbidity was 37%. The 3- and 5-year survival rates after the second resection were 56.8% and 28.4%, respectively, with a median survival of 42.3 months. Seven patients died (mean survival, 25.7 months; range, 9-58 months) before the end of the study. Six patients were alive with one or more recurrences, and three (24, 51, and 173 months of follow-up) were alive without known recurrence. Survival rates for repeat resections of colorectal liver metastases in selected patients were comparable with those obtained after resection of a first liver metastasis.  相似文献   
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