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21.
PURPOSE: To define patients and tumor characteristics as well as therapy results, patients with pelvic osteosarcoma who were registered in the Cooperative Osteosarcoma Study Group (COSS) were analyzed. PATIENTS AND METHODS: Sixty-seven patients with a high-grade pelvic osteosarcoma were eligible for this analysis. Fifteen patients had primary metastases. All patients received chemotherapy according to COSS protocols. Thirty-eight patients underwent limb-sparing surgery, 12 patients underwent hemipelvectomy, and 17 patients did not undergo definitive surgery. Eleven patients received irradiation to the primary tumor site: four postoperatively and seven as the only form of local therapy. RESULTS: Local failure occurred in 47 of all 67 patients (70%) and in 31 of 50 patients (62%) who underwent definitive surgery. Five-year overall survival (OS) and progression-free survival rates were 27% and 19%, respectively. Large tumor size (P =.0137), primary metastases (P =.0001), and no or intralesional surgery (P <.0001) were poor prognostic factors. In 30 patients with no or intralesional surgery, 11 patients with radiotherapy had better OS than 19 patients without radiotherapy (P =.0033). Among the variables, primary metastasis, large tumor, no or intralesional surgery, no radiotherapy, existence of primary metastasis (relative risk [RR] = 3.456; P =.0009), surgical margin (intralesional or no surgical excision; RR = 5.619; P <.0001), and no radiotherapy (RR = 4.196; P =.0059) were independent poor prognostic factors. CONCLUSION: An operative approach with wide or marginal margins improves local control and OS. If the surgical margin is intralesional or excision is impossible, additional radiotherapy has a positive influence on prognosis.  相似文献   
22.
Conference Announcement the Role and Responsibilities of Health Care Ethics Committees September 30–October 1, 1991 Boston Park Plaza Hotel, Boston, Massachusetts  相似文献   
23.
This article deals with methods and instruments used to identify high risk parents and early developing risks of infants and young children during the pre- and postnatal period in order to develop early intervention strategies based on early diagnosis in the context of parent-child-relationship. The specific experiences of our research approaches, funded by the German ministry of education and research (BMBF) from 2003 to 2007 at the University of Applied Sciences in Potsdam in cooperation with the parent counselling centre "Vom S?ugling zum Kleinkind" are reflected. An interaction and communication focused strategy was developed to help to identify early development risks and resources in the parent-infant-relationship at the age of 0-3 years. After testing the diagnostical approach of this social-emotional development screening (SEE-0-3) in a current evaluation study on a high-risk-population, it was integrated as one module of early diagnosis into the early intervention program "STEEP--Steps toward effective and enjoyable parenting" which is based on the attachment theory. Using a concrete case it will first be discussed which kind of approaches to becoming parents with high risk factors can be developed on the basis of attachment reflecting acting and second which possibilities an interaction and video based concept could offer in the field of early diagnosis and intervention with families of infants and young children.  相似文献   
24.
We present a new family of fourth-order splitting methods with positive coefficients especially tailored for the time integration of linear parabolic problems and,in particular, for the time dependent Schrödinger equation, both in real and imaginarytime. They are based on the use of a double commutator and a modified processor, andare more efficient than other widely used schemes found in the literature. Moreover,for certain potentials, they achieve order six. Several examples in one, two and threedimensions clearly illustrate the computational advantages of the new schemes.  相似文献   
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26.
BACKGROUND: The cellular prion protein (PrPc) plays a central role in prion diseases such as variant Creutzfeldt‐Jakob disease. This disease can be transmitted by blood transfusion. However, the exact kinetics of blood infectivity and the blood fraction carrying infectivity have not yet been identified. STUDY DESIGN AND METHODS: Simian PrPc epitopes were mapped by flow cytometry using monoclonal antibodies (MoAbs). A whole blood/no wash protocol was established, validated, and applied to investigate peripheral blood cell–associated PrPc expression profiles in bovine spongiform encephalopathy (BSE)‐infected cynomolgus monkeys and age‐/sex‐matched controls. In addition, physiologic expression patterns on blood cells and in lymphoid tissues were determined. RESULTS: In BSE‐infected macaques, blood lymphocyte–associated PrPc fluorescence gradually increased years before the onset of clinical signs (pF test < 0.0001). The increase in fluorescence intensity was detectable with MoAb 12F10, whereas we failed to detect an increase with 3F4. In parallel, plasma concentrations of soluble CD230 also increased. Centrifugation of lymphocytes almost completely eliminated differences between infected and noninfected animals, most likely caused by a partial loss in cell‐associated CD230 into the plasma supernatant. CONCLUSION: Blood lymphocytes from asymptomatically infected as well as diseased macaques were characterized by increased CD230 fluorescence, and phosphatidylinositol‐phospholipase C–resistant PrP molecules contributed at least partially to this increase. Conformational changes within PrPc molecules may be the underlying mechanism for the increased PrPc fluorescence. This cell‐associated phenomenon contributed at least partially to an increase in soluble plasma‐derived PrPc levels. It is not yet known whether these changes reflect infectivity.  相似文献   
27.
Airway inflammation and remodeling in chronic asthma are characterized by airway eosinophilia, hyperplasia of goblet cells and smooth muscle, and subepithelial fibrosis. We examined the role of leukotrienes in a mouse model of allergen-induced chronic lung inflammation and fibrosis. BALB/c mice, after intraperitoneal ovalbumin (OVA) sensitization on Days 0 and 14, received intranasal OVA periodically Days 14-75. The OVA-treated mice developed an extensive eosinophil and mononuclear cell inflammatory response, goblet cell hyperplasia, and mucus occlusion of the airways. A striking feature of this inflammatory response was the widespread deposition of collagen beneath the airway epithelial cell layer and also in the lung interstitium in the sites of leukocytic infiltration that was not observed in the saline-treated controls. The cysteinyl leukotriene(1) (CysLT(1)) receptor antagonist montelukast significantly reduced the airway eosinophil infiltration, mucus plugging, smooth muscle hyperplasia, and subepithelial fibrosis in the OVA-sensitized/challenged mice. The presence of Charcot-Leyden-like crystals in airway macrophages and the increased interleukin (IL)-4 and IL-13 mRNA expression in lung tissue and protein in BAL fluid seen in OVA-treated mice were also inhibited by CysLT(1) receptor blockade. These data suggest an important role for cysteinyl leukotrienes in the pathogenesis of chronic allergic airway inflammation with fibrosis.  相似文献   
28.

Purpose

The recently introduced Cancer Communication Assessment Tool (CCAT-PF) measures congruence in patient–caregiver communication and was initially validated in lung cancer patients. Contributing to a greater proportion of the variance in the conflict scores, primary caregivers were hypothesized to experience greater stress. For a detailed understanding of conflicting communication patterns of cancer-affected families, our study aimed for psychometric validation of the CCAT-PF in a sample covering heterogeneous tumor entities.

Methods

Subsequent to a cross-sectional survey of 189 pairs of cancer patients (31 % gastrointestinal, 34 % lung, and 35 % urological) and their caregivers’ exploratory factor analysis with principal component condensation and varimax rotation was conducted (response rate, 74.2 %). Reliability and construct validity were assessed calculating Cronbach’s α and Pearson correlation coefficients for CCAT-P and CCAT-F scales and related constructs, respectively.

Results

Cancer-related communication according to the CCAT-PF can be subdivided into four factors including the scales Disclosure, Limitation of treatment, Family involvement in treatment decisions, and Continuing treatment. Reliability ranged from α?=?.51–.68. The Disclosure scale, describing poor cancer-related communication of the patient, was correlated with patient’s distress (QSC-R10: r?=?.30, p?<?.0001), unmet needs in several areas (SCNS-SF-34: r?=?.25–.32, p?<?.001), and negatively with social/family well-being (FACT: r?=??0.31, p?<?.0001). Higher scores on the scale were significantly associated with considerable decrements in emotional well-being especially for caregivers perceiving patients’ disclosure as problematic.

Conclusions

The Disclosure scale originating from the CCAT-PF emerged as a short, valid, and reliable stand-alone instrument for identifying conflicting communication in patient–caregiver–dyads at risk.  相似文献   
29.

Background

Chronic severe pulmonary regurgitation (PR) causes progressive right ventricular (RV) dysfunction and heart failure. Parameters defining the optimal time point for surgery of chronic PR are lacking. The present study prospectively evaluated the impact of preoperative clinical parameters, cardiorespiratory function, QRS duration and NT-proBNP levels on post operative RV function and volumes assessed by cardiac magnetic resonance imaging (CMR) in patients with chronic severe PR undergoing pulmonary valve replacement.

Methods and results

CMR was performed pre- and 6 months postoperatively in 27 patients (23.6 ± 2.9 years, 15 women) with severe PR. Postoperatively, RV endsystolic (RVESVI) and enddiastolic volume indices (RVEDVI) decreased significantly (RVESVI pre 78.2 ± 20.4 ml/m² BSA vs. RVESVI post 52.2 ± 16.8 ml/m²BSA, p < 0.001; RVEDVI pre 150.7 ± 27.7 ml/m²BSA vs. RVEDVI post 105.7 ± 26.7 ml/m²BSA; p < 0,001). With increasing preoperative QRS-duration, postoperative RVEF decreased significantly (r =−0.57; p < 0.005). Preoperative QRS-duration smaller than the median (156 ms) predicted an improved RVEF compared to QRS-duration ≥ 156 ms (54.9% vs 46.8%, p < 0.05). Multivariate analysis identified preoperative QRS duration as an independent predictor of postoperative RVEF (p < 0.005). NT-proBNP levels correlated with changes in RVEDI (r = 0.58 p < 0,005) and RVESVI (r = 0.63; p < 0,0001). Multivariate analysis identified NT-proBNP levels prior to PVR as an independent predictor of volume changes (p < 0.05).

Conclusion

Valve replacement in severe pulmonary regurgitation causes significant reduction of RV volumes. Both, preoperative NT-proBNP level elevation and QRS prolongation indicate patients with poorer outcome regarding RV function and volumes.  相似文献   
30.
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