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PurposeTo evaluate the clinical outcome after CT-guided interstitial high-dose-rate (HDR) brachytherapy for dose escalation in the radiotherapy treatment of inoperable locally advanced non–small-cell lung cancer (NSCLC).Methods and MaterialsFrom 2005 to 2015, 16 patients with unresectable NSCLC were treated. Median age was 65.7 years (range, 52–86). The median tumor volume was 95.3 cm3 (range, 20.0–2000.0). The median prescribed HDR was 15.0 Gy (range, 7.0–32.0) delivered in twice-daily fractions of 6.0–8.0 Gy in 4 patients and in once-daily fractions of 7.0–15.0 Gy in 12 patients, respectively.ResultsAfter a median followup of 12.5 months, median overall survival and local control was 12.9 and 24.9 months, respectively. The corresponding median overall survival and local control rates at 1, 2, and 3 years were 56.2%, 37.5%, and 12.5% as well as 68.9%, 57.4%, and 43%, respectively. Apart from one Grade 1 cough episode persisting for 1 week and one patient developing a minor hemopneumothorax requiring no postprocedural drainage, no other adverse events were recorded.ConclusionsCT-guided interstitial HDR brachytherapy is a safe modality for radiation dose escalation which may play a role in the definitive radiotherapy treatment of locally advanced NSCLC.  相似文献   
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Previous studies have shown that in vitro exposure to single compounds released from composite resins may induce cell death. In the present study the effects of eluates from commercially available composite resins used for direct or indirect restorations were evaluated on the cell cycle progression and type of cell death of cultured WEHI 13 var fibroblasts. Cells exposed to eluates of the materials were assessed for cytotoxicity by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay for cell death, for cell cycle profiles by flow cytometry, for caspase-3 biochemically and by immunocytochemistry, and for morphological changes by fluorescence microscopy with acridine orange. The direct composite resin eluates induced extensive apoptosis, followed by secondary necrosis. This was accompanied by cell enlargement, micromultinucleation, chromatin disintegration, cell cycle arrest at different phases, and caspase-3 activation. The composites for indirect restorations were much less cytotoxic at all biological end-points investigated. The findings suggest that composite resins used for direct and indirect dental restorations differ in their cytotoxic potential and their ability to affect basic cellular functions. This underlines the impact of improved polymerization with respect to their biologic behavior.  相似文献   
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BACKGROUND: This study investigates the correlation of hepatic progenitor cells (HPC) expression with treatment response in patients with chronic hepatitis C. DESIGN: The study comprised 77 liver biopsies with chronic hepatitis C (HCV). All patients were PCR-HCV (+) and received antiviral therapy with interferon or pegylated interferon alpha-2b and ribavirin. Twenty-nine patients were assigned as responders (group A), 29 as nonresponders (group B) and 19 as relapsers (group C). Ten normal liver biopsies were used as controls. Liver paraffin sections were subjected (a) to immunohistochemistry using antibodies for cytokeratins 19 (CK19) and 7 (CK7), alpha-fetoprotein (AFP), leukocyte common antigen (LCA) and CD34 antigen (b) to in situ hybridization for AFP mRNA and (c) to immunohistochemistry+in situ hybridization. Results were expressed as % of positive cells following morphometric analysis. RESULTS: HPC expression was present in all 87 specimens. In the control biopsies, rare HPC were detected. In the CH cases and according to AFP mRNA expression, the grade for % HPC expression was: group B: 53.2+/-2.6> group C: 48.37+/-1.8> group A: 31.4+/-1.6 (group A vs B P<0.01, group A vs C P<0.01, group B vs C P>0.05. Double stain revealed that HPC coexpressed CK19/AFP mRNA, CK7/AFP mRNa and AFP protein/AFP mRNA. HPC-percentages were directly correlated with total HAI score (P<0.01), fibrosis stage (P<0.01), and transaminase values (P<0.05). CONCLUSIONS: This study demonstrates that in cases of chronic hepatitis C, the significant association of HPC expression with the severity of disease and more specifically with the response to treatment implies that HPC development and proliferation may provide additional prognostic information and predict prognosis in such cases.  相似文献   
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Positron emission tomography (PET) targeting the 18 kDa translocator protein (TSPO) is used to quantify neuroinflammation. Translocator protein is expressed throughout the brain, and therefore a classical reference region approach cannot be used to estimate binding potential (BPND). Here, we used blockade of the TSPO radioligand [11C]PBR28 with the TSPO ligand XBD173, to determine the non-displaceable volume of distribution (VND), and hence estimate the BPND. A total of 26 healthy volunteers, 16 high-affinity binders (HABs) and 10 mixed affinity binders (MABs) underwent a [11C]PBR28 PET scan with arterial sampling. Six of the HABs received oral XBD173 (10 to 90 mg), 2 hours before a repeat scan. In XBD173-dosed subjects, VND was estimated via the occupancy plot. Values of BPND for all subjects were calculated using this VND estimate. Total volume of distribution (VT) of MABs (2.94±0.31) was lower than VT of HABs (4.33±0.29) (P<0.005). There was dose-dependent occupancy of TSPO by XBD173 (ED50=0.34±0.13 mg/kg). The occupancy plot provided a VND estimate of 1.98 (1.69, 2.26). Based on these VND estimates, BPND for HABs is approximately twice that of MABs, consistent with predictions from in vitro data. Our estimates of [11C]PBR28 VND and hence BPND in the healthy human brain are consistent with in vitro predictions. XBD173 blockade provides a practical means of estimating VND for TSPO targeting radioligands.  相似文献   
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Existing research underscores the significance of early childhood experiences in the childcare context for the development of socioemotional skills and competencies. However, the practices adopted within childcare for the enhancement of children's socioemotional development and the factors mediating these practices are less adequately researched. The present study contributes to this understanding, through studying the perceptions of 34 educators working in childcare centres in Greece with regard to children's socioemotional development and its promotion. Results showed that although they acknowledged the significance of social and emotional competencies for children's adjustment, learning and well-being, they did not report consistent use of practices having as a goal the promotion of such skills. Explanations involve on the one hand the lack of formal policy and the existence of structural barriers and on the other hand a perception that socioemotional development is mostly affected by factors beyond their influence. Results are discussed in relation to prior research and in terms of their implications for designing interventions, curricula and staff training.  相似文献   
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OBJECTIVES: Synergism between gemcitabine and cisplatin is supported by preclinical and clinical data. The present study explores the efficacy of a biweekly regimen in platinum-resistant/refractory, paclitaxel-pretreated ovarian and peritoneal cancer. METHODS: 50 paclitaxel-pretreated patients with platinum-resistant/refractory ovarian or peritoneal carcinoma who had previously received paclitaxel chemotherapy, were treated with six cycles of gemcitabine 1000 mg/m(2) followed by cisplatin 40 mg/m(2) on days 1 and 15, repeated every 4 weeks. RESULTS: The median platinum-free interval (PFI) was 4 months while the median number of previous treatment lines was 2. Chemotherapy was well tolerated. Objective responses were observed in 31.5% of evaluable patients (n=35). CA125 response was observed in 68% of patients with elevated CA125 (n=41). Median overall survival (OS) was 13.2 months (95% Confidence Interval, CI: 10.2-16.2) while progression-free survival (PFS) was 4.9 months (95%CI: 3.5-6.4). A PFI of less than 3 months was associated with lower objective response rates (15.8% versus 50%, p=0.03). CONCLUSIONS: Biweekly gemcitabine and cisplatin is feasible for patients with platinum-resistant ovarian or peritoneal cancer and is associated with a favorable toxicity profile. In a population with recent exposure to platinum, a PFI of less than 3 months was the major factor influencing response to chemotherapy.  相似文献   
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