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991.
992.
OBJECTIVES: To develop the European League Against Rheumatism (EULAR) recommendations for conducting clinical studies and/or clinical trials in systemic vasculitis. METHODS: An expert consensus group was formed consisting of rheumatologists, nephrologists and specialists in internal medicine representing five European countries and the USA, a clinical epidemiologist and representatives from regulatory agencies. Using an evidence-based and expert opinion-based approach in accordance with the standardised EULAR operating procedures, the group identified nine topics for a systematic literature search through a modified Delphi technique. On the basis of research questions posed by the group, recommendations were derived for conducting clinical studies and/or clinical trials in systemic vasculitis. RESULTS: Based on the results of the literature research, the expert committee concluded that sufficient evidence to formulate guidelines on conducting clinical trials was available only for anti-neutrophil cytoplasm antibody-associated vasculitides (AAV). It was therefore decided to focus the recommendations on these diseases. Recommendations for conducting clinical trials in AAV were elaborated and are presented in this summary document. It was decided to consider vasculitis-specific issues rather than general issues of trial methodology. The recommendations deal with the following areas related to clinical studies of vasculitis: definitions of disease, activity states, outcome measures, eligibility criteria, trial design including relevant end points, and biomarkers. A number of aspects of trial methodology were deemed important for future research. CONCLUSIONS: On the basis of expert opinion, recommendations for conducting clinical trials in AAV were formulated. Furthermore, the expert committee identified a strong need for well-designed research in non-AAV systemic vasculitides.  相似文献   
993.
BACKGROUND: The classification of antineutrophil cytoplasmic antibody-associated vasculitis (AAV) and polyarteritis nodosa (PAN) for epidemiology studies is confusing. The existing schemes such as American College of Rheumatology (ACR) criteria, Chapel Hill Consensus Conference (CHCC) definitions and Lanham criteria produce overlapping and conflicting classifications, making it difficult to compare incidence figures. Aim: To develop a consensus method of using these criteria and definitions for epidemiological studies to permit comparison without confounding by classification. METHODS: A stepwise algorithm was developed by consensus between a group of doctors interested in the epidemiology of vasculitis. The aim was to categorise patients with Wegener's granulomatosis, microscopic polyangiitis (MPA), Churg-Strauss syndrome (CSS) and PAN into single clinically relevant categories. The ACR and Lanham criteria for CSS, and ACR criteria for Wegener's granulomatosis were applied first, as these were considered to be the most specific. Surrogate markers for Wegener's granulomatosis were included to distinguish Wegener's granulomatosis from MPA. MPA was classified using the CHCC definition and surrogate markers for renal vasculitis. Finally, PAN was classified using the CHCC definition. The algorithm was validated by application to 20 cases from each centre and 99 from a single centre, followed by a paper case exercise. RESULTS: A four-step algorithm was devised. It successfully categorises patients into a single classification. There was good correlation between observers in the paper case exercise (91.5%; unweighted kappa = 0.886). CONCLUSION: The algorithm achieves its aim of reliably classifying patients into a single category. The use of the algorithm in epidemiology studies should permit comparison between geographical areas.  相似文献   
994.
Dose-intensity of chemotherapy is important in the treatment of Hodgkin lymphoma (HL) and granulocyte-colony stimulating factor (G-CSF) is commonly used to maintain it. We reviewed all newly diagnosed HL patients who were treated at our institution between 1996 and 2005. Fifty-nine patients received adriamycin, bleomycin, vinblastine, and dacarbazine (ABVD) chemotherapy with no dose reductions, treatment delays, and without G-CSF, regardless of absolute neutrophil count (ANC). The median ANC on all ABVD treatment days (n = 658) was 0.925 x 10(9)/l, and was <0.5 x 10(9)/l on 26% of treatment days. Median normalised ABVD dose-intensity was 99.1% (range, 93-100%) and median cycle duration was 28.2 d. Incidence of bleomycin lung toxicity was 1.6%, 0.44% treatments were complicated by febrile neutropenia, and no secondary malignancies have occurred (median follow-up 48 months; range, 11-130 months). Five-year event-free (EFS) and overall survival (OS) were 92.9% and 97.4% respectively. Furthermore, the 5-year EFS and OS (87.4% and 94.1% respectively) for advanced stage patients compared favourably with a similar ABVD patient group who received routine prophylactic G-CSF (n = 23) with EFS 80.0% and OS 91.3% (P = 0.46 and 0.67 respectively). Our experience suggests that ABVD may be safely and effectively administered at >99% dose-intensity without G-CSF support, regardless of the ANC.  相似文献   
995.
996.
997.
BACKGROUND: Sarcomas arising in the heart or the great vessels are rare entities. The prognosis of the patients is dismal. METHODS: Between January 1993 and September 2006, of 1,429 patients registered to the Sarcoma Center, 14 had a primary sarcoma of the heart or large vessels. RESULTS: Tumors were located in the left ventricle (n = 3), left/right atrium (n = 2/3), pulmonary artery (n = 2), and ventricular septum, aorta, pericardium, and inferior vena cava (n = 1 each). The most frequently encountered histologic subtypes were leiomyosarcoma and angiosarcoma. Six patients presented with distant metastases to the lungs (n = 5), lymph nodes (n = 2), and liver (n = 1). Eight patients had localized disease. Six of them underwent resection with curative intent. Of those, two developed local recurrence within 2 and 10 months from surgery. Eleven patients received palliative chemotherapy, seven of those as initial treatment. Eight patients attained a response to treatment, two had disease stabilization for 6 and 12 months. After a median follow-up of 14.5 months (range, 2-156), three patients were alive with no evidence of disease 11, 52, and 156 months after diagnosis. Two patients were alive with disease and nine patients had died. CONCLUSIONS: Patients with primary sarcomas of the heart and the large vessels were of a young age, and more than half of them presented with advanced disease. Given the promising response to chemotherapy, an optimized treatment approach including neoadjuvant chemo-/radiotherapy in patients with locally advanced disease should be pursued.  相似文献   
998.
Sabel MS  Arora A  Su G  Mathiowitz E  Reineke JJ  Chang AE 《Surgery》2007,142(5):749-760
Neoadjuvant immunotherapy with the combination of intratumoral IL-12 and TNF-alpha encapsulated in poly-lactic acid microspheres (PLAM) generate a greater systemic immune response than either cytokine alone. We sought to examine the effector cells responsible for this synergy using the poorly immunogenic B16 melanoma and MCA205 sarcoma cell lines. Splenocytes from MCA205 bearing mice treated with IL-12 and TNF-alpha PLAM contained significantly more tumor-specific IFN-gamma secreting cells than IL-12 alone. Adoptive transfer of lymphocytes from mice treated by the combination mediated significant tumor regression in mice bearing established pulmonary metastases. In mice bearing bilateral tumors, treatment of the primary with IL-12 and TNF-alpha PLAM, resulted in suppression of contralateral tumor growth. Both the local and distant effects were absent in mice depleted of CD8+ T-cells. In B16 bearing mice with established pulmonary disease, only the combination of intratumoral IL-12 and TNF-alpha resulted in a significant reduction of lung nodules. Both the local and distant effects were eradicated in mice depleted of either CD8+ T-cells or NK cells. The local and sustained release of IL-12 and TNF-alpha using PLAM synergistically activate both a cytotoxic T-cell and NK cell response, although their impact varies with MHC class I expression.  相似文献   
999.
1000.
Smoking-related self-efficacy and beliefs about the benefits of smoking are consistently related to intention to continue smoking, a common proximal outcome in youth smoking cessation studies. Some measures of these constructs are used frequently in national and state youth tobacco surveys, despite little evidence of validity for high school smokers. Further, the association of the constructs with intention has not been demonstrated in this group. The factorial validity of the measures and the cross-sectional correlations among self-efficacy, beliefs, and intention were examined among 9th-12th grade current smokers (N=2,767, 13.8% reporting smoking >1 cigarette in the previous 30 days; mean age 16.2; 61.2% white, 6.2% Black, 17.8% Hispanic, 5.0% Asian, 3.5% other; response rate 70%) from a convenience sample of 22 Texas schools. Confirmatory factor analyses supported evidence of factorial validity for the scales in this sample. Structural equation modeling analyses suggested youth smokers have low confidence in their ability to avoid smoking, believe smoking offers emotional or social benefits, and intend to continue smoking. The scales assess smoking-related self-efficacy, beliefs, and intention in this sample. Prospective studies are needed before intervention development implications are suggested.  相似文献   
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