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1.

Objective

Comparative survival between neoadjuvant chemotherapy and adjuvant chemotherapy for patients with cT2-4N0-1M0 non–small cell lung cancer has not been extensively studied.

Methods

Patients with cT2-4N0-1M0 non–small cell lung cancer who received platinum-based chemotherapy were retrospectively identified. Exclusion criteria included stage IV disease, induction radiotherapy, and targeted therapy. The primary end point was disease-free survival. Secondary end points were overall survival, chemotherapy tolerance, and ability of Response Evaluation Criteria In Solid Tumors response to predict survival. Survival was estimated using the Kaplan–Meier method, compared using the log-rank test and Cox proportional hazards models, and stratified using matched pairs after propensity score matching.

Results

In total, 330 patients met the inclusion criteria (n = 92/group after propensity-score matching; median follow-up, 42 months). Five-year disease-free survival was 49% (95% confidence interval, 39-61) for neoadjuvant chemotherapy versus 48% (95% confidence interval, 38-61) for adjuvant chemotherapy (P = .70). On multivariable analysis, disease-free survival was not associated with neoadjuvant chemotherapy or adjuvant chemotherapy (hazard ratio, 1.1; 95% confidence interval, 0.64-1.90; P = .737), nor was overall survival (hazard ratio, 1.21; 95% confidence interval, 0.63-2.30; P = .572). The neoadjuvant chemotherapy group was more likely to receive full doses and cycles of chemotherapy (P = .014/0.005) and had fewer grade 3 or greater toxicities (P = .001). Response Evaluation Criteria In Solid Tumors response to neoadjuvant chemotherapy was associated with disease-free survival (P = .035); 15% of patients receiving neoadjuvant chemotherapy (14/92) had a major pathologic response.

Conclusions

Timing of chemotherapy, before or after surgery, is not associated with an improvement in overall or disease-free survival among patients with cT2-4N0-1M0 non–small cell lung cancer who undergo complete surgical resection.  相似文献   
2.
Head movement presents a continuing problem in PET studies. Head restraint minimizes movement but is unreliable, resulting in the need to develop alternative strategies. These include frame-by-frame (FBF) realignment or use of motion tracking (MT) during the scan to realign PET acquisition data. Here we present a comparative analysis of these 2 methods of motion correction. METHODS: Eight volunteers were examined at rest using (11)C-raclopride PET with the radioligand administered as a bolus followed by constant infusion to achieve steady state. Binding potential (BP) was estimated using the ratio method during 2 periods of the scan at steady state. Head movement was compensated by using coregistration between frames (FBF) and 3 methods using MT measurements of head position acquired with a commercially available optical tracking system. RESULTS: All methods of realignment improved test-retest reliability and noise characteristics of the raw data, with important consequences for the power to detect small changes in radiotracer binding, and the potential to reduce false-positive and false-negative results. MT methods were superior to FBF realignment using coregistration on some indices. CONCLUSION: Such methods have considerable potential to improve the reliability of PET data with important implications for the numbers of volunteers required to test hypotheses.  相似文献   
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PURPOSE: The use of gefitinib, the first drug approved to inhibit the epidermal growth factor receptor tyrosine kinase, is indicated in patients with non-small-cell lung cancer with tumors progressive after chemotherapy. The unique mechanism of action of this agent leads to distinctive patterns of response and toxicity in persons with lung cancer. Many of the principles of management relevant to gefitinib are distinct from those with conventional cytotoxic drugs. To meet this need, we present practical guidelines on the use of gefitinib in patients with non-small-cell lung cancer. METHODS: This article reviews gefitinib's indications, dosing, response phenomena, and patterns of relapse in individuals with radiographic response. RESULTS: We present our recommendations for the management of rash and diarrhea caused by this agent. CONCLUSION: This information can guide practitioners and help them inform their patients about what to expect when they receive gefitinib.  相似文献   
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This paper, written by two male nurse teachers, describes and analyses their experience of working in a nurse education culture permeated by the philosophy of business management The introduction of business management practices to nurse education is discussed as a reflection of the current political hegemony of market forces and individualism The authors discuss the implications for nurse teachers of being continually exposed to these politically motivated forces which increasingly provide the paradigm for service developments within the United Kingdom health services In discussing the impact of this exposure it is argued that at the personal level individual teachers are experiencing a degree of apathy and personal dissonance which undermines their professional value system, resulting in emotional distress and a crisis of identity It provides a critical reflection on the way organizational dynamics and power relations influence the subjective sense-making of individuals The authors use a multiplicity of perspectives, including those provided by individual psychology, power relations, feminism and personhood, to argue for the need to develop an alternative paradigm which is characterized by the valuing of individual persons, empathic sensitivity and the fostering of creativity been important to us from a personal and professional  相似文献   
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The research describes how nursing staff on a general surgical ward in a district general hospital perceived the delivery method of nursing care in practice. The study design was based on ethnographic methods and data were collected by diary keeping and semi-structured interviews. An organizational method based on the principles of primary nursing had been implemented on the ward for 2 years prior to the study commencing. As well as talking in general terms about primary nursing, the nursing staff talked at some length about specific issues related to their practice.  相似文献   
9.
What should nurse teachers be doing? A preliminary study   总被引:1,自引:0,他引:1  
There is little doubt that the role of the nurse teacher is complex and multifaceted in nature. The apparently conflicting demands of NHS trusts and education in the United Kingdom, at the time of integration of nurse education into the higher education sector, further complicates the role. This recognition underlines the need to capture and measure key aspects of nurse teacher function in order to maximize educational gain. Using a comprehensive literature review, focus group discussions and a small number of individual semi-structured interviews, this preliminary study explored the issue of teacher workload, from the perspective of the principal stakeholders in nurse and higher education. Competing research and clinical practice objectives for nurse teachers are identified against a background of changing health care provision, reduced availability of placements and an increased need for evidence-based practice.  相似文献   
10.
Introduction: Features of spiral CT (SCT) — fast scanning, dynamic injection of contrast allowing optimal vessel opacification, and supplemental multiplanar imaging — promises to provide increased accuracy in the diagnosis of acute and non acute thoracic vascular disease. Recent work demonstrating the cost effective triage of hemodynamically stable patients after blunt chest trauma for angiography based on dynamic CT findings has prompted an investigation into the accuracy of SCT in this clinical setting. Methods: A retrospective review of all patients seen in the emergency department over the period of one year for aortic, thoracic, or blunt chest trauma evaluation was performed (74 patients) and all SCT scans available were reviewed and data reformatted for optimal delineation of pathology using maximum intensity projection and multiplanar reformation. The accuracy and predictive positive and negative values of SCT were calculated with respect to angiography, surgical, and/or clinical follow up evaluation. Results: Twenty three (31%) patients went directly to angiography owing to mediastinal widening on chest film and hemodynamic instability, of which four were positive and required emergent surgery. Seven hemodynamically stable patients (9%) had noncontrast SCT owing to mediastinal widening on chest film, all of which had angiography with none having great vessel trauma. Fourty four hemodynamically stable patients (60%) had contrast enhanced SCT (ceSCT), of which five (11%) were abnormal and underwent angiography, four of these were positive for aortic damage, one for a subclavian artery laceration. Of the remaining 39 patients who had normal ceSCT; five had angiography, all of which were normal. Of the remaining 34 patients that had normal ceSCT none had adverse outcome on clinical follow-up, minimum of 12 months. Conclusion: The predictive positive value for aortic trauma of ceSCT in blunt trauma is 80%, with a predictive negative value of 100%, indicating that it is feasible for SCT to be a first line exam in blunt chest trauma in the future.  相似文献   
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