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排序方式: 共有1147条查询结果,搜索用时 15 毫秒
11.
José S A Belderbos Katrien De Jaeger Wilma D Heemsbergen Yvette Seppenwoolde Paul Baas Liesbeth J Boersma Joos V Lebesque 《Radiotherapy and oncology》2003,66(2):119-126
PURPOSE: To evaluate the feasibility of dose escalation in non-small cell lung cancer (NSCLC) using three-dimensional conformal radiation therapy. PATIENTS AND METHODS: The main eligibility criteria of the trial were: pathologically proven inoperable NSCLC, ECOG performance status or=grade 3 (SWOG), grade 3 early and grade 2 late esophageal toxicity or any other (RTOG) grade 3 or 4 complications). RESULTS: Fifty-five patients were included. Tumor stage was I/II in 47%, IIIA in 33% and IIIB in 20%. The majority of the patients received a dose of 74.3 Gy (n=17) or 81.0 Gy (n=23). Radiation pneumonitis occurred in seven patients: four patients developed a grade 2, two patients grade 3 and one patient a grade 4. Esophageal toxicity was mild. In 50 patients tumor response at 3 months follow-up was evaluable. In six patients a complete response was recorded, in 38 a partial response, five patients had stable disease and one patient experienced progressive disease. Only one patient developed an isolated failure in an uninvolved nodal area. So far the radiation dose was safely escalated to 87.8 Gy in group 1 (lowest rMLD), 81.0 Gy in groups 2 and 3 and 74.3 Gy in group 4. CONCLUSION: Three-dimensional conformal radiotherapy enables significant dose escalation in NSCLC. The maximum tolerable dose has not yet been reached in any risk group. 相似文献
12.
After we incidentally found on CT extensive esophageal fat accumulations in a patient with long-term use of steroids, we
prospectively evaluated during a 6-month period all CT studies of the chest for esophageal lipomatosis and related the findings
to the possible use of steroids. The diagnosis of esophageal fat on CT was made by density measurements or if too small for
reliable density measurements by comparison with mediastinal fat. In 21 of 1320 exclusively older male patients the diagnosis
of esophageal lipomatosis was definite in 7 and likely in 14 patients. All fat accumulations were located in the upper third
of the esophagus (mean length 22 ± 6 mm) and presented ring-like (n = 10), irregular (n = 3), or as a horseshoe sparing the posterior border (n = 8). In 20 patients there was an unequivocal history of steroid treatment. Associated centripetal fat infiltration was found
in 11 patients. None of the patients had swallowing problems. Prolonged use of steroids, either orally or inhalationally administered,
is associated with esophageal lipomatosis. The predisposition for the upper esophagus might be related to the presence of
striated muscle cells in this part of the esophagus; moreover, inhalational steroid therapy may adversely affect the upper
esophagus.
Received: 3 April 2000; Accepted: 2 May 2000 相似文献
13.
Dirk De Ruysscher Stofferinus Wanders Andre Minken Aniek Lumens Jacqueline Schiffelers Cissie Stultiens Serve Halders Liesbeth Boersma Angela van Baardwijk Tom Verschueren Monique Hochstenbag Gabriel Snoep Brad Wouters Sebastiaan Nijsten S?ren M Bentzen Marinus van Kroonenburgh Michel Ollers Philippe Lambin 《Radiotherapy and oncology》2005,77(1):5-10
BACKGROUND AND PURPOSE: To investigate the effect of radiotherapy planning with a dedicated combined PET-CT simulator of patients with locally advanced non-small cell lung cancer. PATIENTS AND METHODS: Twenty-one patients underwent a pre-treatment simulation on a dedicated hybrid PET-CT-simulator. For each patient, two 3D conformal treatment plans were made: one with a CT based PTV and one with a PET-CT based PTV, both to deliver 60Gy in 30 fractions. The maximum tolerable prescribed radiation dose for CT versus PET-CT PTV was calculated based on constraints for the lung, the oesophagus, and the spinal cord, and the Tumour Control Probability (TCP) was estimated. RESULTS: For the same toxicity levels of the lung, oesophagus and spinal cord, the dose could be increased from 55.2+/-2.0Gy with CT planning to 68.9+/-3.3Gy with the use of PET-CT (P=0.002), with corresponding TCP's of 6.3+/-1.5% for CT and 24.0+/-5.6% for PET-CT planning (P=0.01). CONCLUSIONS: The use of a combined dedicated PET-CT-simulator reduced radiation exposure of the oesophagus and the lung, and thus allowed significant radiation dose escalation whilst respecting all relevant normal tissue constraints. 相似文献
14.
Aisha S. Sie Judith B. Prins Liesbeth Spruijt C. Marleen Kets Nicoline Hoogerbrugge 《Familial cancer》2013,12(4):675-682
DNA-testing for BRCA1/2 or Lynch syndrome is possible from the age of 18 years, although surveillance usually starts at 25. Some patients regret their decision of testing before age 25. This retrospective study evaluates whether the testing age should be above 25 years to prevent adverse effects such as regret or decisional conflict, by determining the percentage and characteristics of patients reporting these problems. 111 of 219 patients (51 %) tested for BRCA1/2 mutations or Lynch syndrome between 18 and 25 years from July 1996 to February 2011, returned self-report surveys. Primary measures were regret, decisional conflict and family influence. Secondary measures included quality of life (QoL), coping style, impact of genetic testing, and risk perception. Median age was 27 [21–40] years, with 86 % female. 73 % was tested for BRCA1/2, 27 % for Lynch syndrome. Only 3 % reported regret, however 39 % had moderate (32 %) to severe (7 %) decisional conflict. Regression analysis revealed that decisional conflict was associated with more monitoring/neutral coping style (p < 0.03) or paternal/no family mutation (p < 0.02); there were no differences in QoL, impact or risk perception. 42 % were mutation carriers, showing equal decisional conflict to non-carriers. 68 % would recommend testing <25 years; 77 % desired surveillance <25 years if a mutation carrier. Almost no patient tested for hereditary cancer between 18 and 25 years regretted this decision. A third reported retrospective decisional conflict, especially those actively seeking information when faced with a threat and/or those with a paternal or unknown inheritance. These patients may benefit from decisional support and personalized information. 相似文献
15.
Chantal Lammens Eveline Bleiker Neil Aaronson Annette Vriends Margreet Ausems Maaike Jansweijer Anja Wagner Rolf Sijmons Ans van den Ouweland Rob van der Luijt Liesbeth Spruijt Encarna Gómez García Mariëlle Ruijs Senno Verhoef 《Familial cancer》2009,8(4):457-464
The use of pre-implantation genetic diagnosis (PGD) for hereditary cancer is subject to on-going debate, particularly among professionals. This study evaluates the attitude towards PGD and attitude-associated characteristics of those concerned: family members with a hereditary cancer predisposition. Forty-eight Von Hippel-Lindau and 18 Li–Fraumeni Syndrome families were identified via the 9 family cancer clinics in the Netherlands. In total, 216 high risk family members and partners were approached, of whom 179 (83%) completed a self-report questionnaire. Of the high risk family members, 35% expressed a positive attitude towards PGD. Those with a current desire to have children were significantly more likely to have a positive attitude: 48% would consider the use of PGD. No other sociodemographic, medical or psychosocial variables were associated significantly with a positive attitude. The most frequently reported advantage of PGD is the avoidance of a possible pregnancy termination. Uncertainty about late effects was the most frequently reported disadvantage. These results indicate that approximately half of those contemplating a future pregnancy would consider the use of PGD. The actual uptake, however, is expected to be lower. There is no indication that psychosocial factors affect interest in PGD. 相似文献
16.
Jonathan Luyten Noëmi M. C. De Roo Jeroen Christiaens Leonie Van Overberghe Liesbeth Temmerman Guy A. M. De Pauw 《The Angle orthodontist》2023,93(1):95
ObjectivesTo compare the dentoalveolar outcomes of slow maxillary expansion (SME) and rapid maxillary expansion (RME) used for maxillary expansion before secondary alveolar bone grafting in patients with cleft lip and/or palate (CL/P). Secondarily, the advantages and disadvantages of SME vs RME were reviewed.Materials and MethodsA systematic search was conducted up to November 2021, including Medline (via PubMed), Embase (via Ovid), Web of Science, Cochrane Central, and Google Scholar. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed. Risk-of-bias assessment was performed using the Risk of Bias (RoB 2.0) and Risk Of Bias In Non-randomized Studies of Interventions (ROBINS I) tool. Overall quality was assessed using the Grading of Recommendations Assessment, Development, and Evaluation tool.ResultsOf 4007 records, five studies met the inclusion criteria. The randomized control trial (RCT) had a low risk of bias, the non-RCTs presented with a moderate risk of bias. Arch width and perimeter increased significantly with both SME and RME treatments. No difference in the increase in palatal depth was found. The meta-analysis showed a greater anterior-to-posterior expansion ratio for the Quad Helix (QH) appliance. The results for dental tipping were not conclusive.ConclusionsSME and RME promote equal posterior expansion in cleft patients. The anterior differential expansion is greater with SME (QH appliance). No clear evidence exists concerning the amount of dental adverse effects of SME and RME in cleft patients. 相似文献
17.
Åsa Tivesten Liesbeth Vandenput Daniel Carlzon Maria Nilsson Magnus K. Karlsson Östen Ljunggren Elizabeth Barrett-Connor Dan Mellström Claes Ohlsson 《Journal of the American College of Cardiology》2014
Background
The adrenal sex hormone dehydroepiandrosterone (DHEA), which is present in serum mainly as the sulfate DHEA-S, is the most abundant steroid hormone in human blood. Its levels decline dramatically with age. Despite the great amount of literature on vascular and metabolic actions of DHEA/-S, evidence for an association between DHEA/-S levels and cardiovascular events is contradictory.Objectives
This study tested the hypothesis that serum DHEA and DHEA-S are predictors of major coronary heart disease (CHD) and/or cerebrovascular disease (CBD) events in a large cohort of elderly men.Methods
We used gas and liquid chromatography-mass spectrometry to analyze baseline levels of DHEA and DHEA-S in the prospective population-based Osteoporotic Fractures in Men study in Sweden (2,416 men, ages 69 to 81 years). Complete cardiovascular clinical outcomes were available from national Swedish registers.Results
During the 5-year follow-up, 302 participants experienced a CHD event, and 225 had a CBD event. Both DHEA and DHEA-S levels were inversely associated with the age-adjusted risk of a CHD event; the hazard ratios and 95% confidence intervals per SD increase were 0.82 (0.73 to 0.93) and 0.86 (0.77 to 0.97), respectively. In contrast, DHEA/-S showed no statistically significant association with the risk of CBD events. The association between DHEA and CHD risk remained significant after adjustment for traditional cardiovascular risk factors, serum total testosterone and estradiol, C-reactive protein, and renal function, and remained unchanged after exclusion of the first 2.6 years of follow-up to reduce reverse causality.Conclusions
Low serum levels of DHEA and its sulfate predict an increased risk of CHD, but not CBD, events in elderly men. 相似文献18.
Rooms L Reyniers E van Luijk R Scheers S Wauters J Ceulemans B Van Den Ende J Van Bever Y Kooy RF 《Human mutation》2004,23(1):17-21
Subtelomeric rearrangements are responsible for 5% to 10% of cases of unexplained mental retardation. Despite their clinical relevance, methods to screen for these cytogenetically invisible abnormalities on a routine base are scarce. We screened patients with idiopathic mental retardation for subtelomeric aberrations using multiplex ligation-dependent probe amplification (MLPA). This recently developed technique is based on PCR amplification of ligated probes hybridized to chromosome ends. Currently, 41 telomeres can be screened in just two multiplex reactions. Four subtelomeric rearrangements (5.3%) were detected in a group of 75 patients with mild to severe mental retardation in combination with dysmorphic features and/or a familial history of mental retardation: two terminal 1p deletions, a terminal 1q deletion, and a terminal 3p deletion. Deletions could be verified by FISH and marker analysis. In one case the MLPA indicated a terminal 21q deletion due to a 3-bp deletion at the site of the probe, giving a false-positive rate of 1.3%. This study demonstrates that MLPA is a fast and reliable screening method, potentially suitable for use in routine diagnostics. 相似文献
19.
In vitro and in vivo studies of a VEGF121/rGelonin chimeric fusion toxin targeting the neovasculature of solid tumors 总被引:3,自引:0,他引:3 下载免费PDF全文
Veenendaal LM Jin H Ran S Cheung L Navone N Marks JW Waltenberger J Thorpe P Rosenblum MG 《Proceedings of the National Academy of Sciences of the United States of America》2002,99(12):7866-7871
Vascular endothelial growth factor (VEGF) plays a key role in the growth and metastasis of solid tumors. We generated a fusion protein containing VEGF(121) linked by a flexible G(4)S tether to the toxin gelonin (rGel) and expressed this as a soluble protein in bacteria. Purified VEGF(121)/rGel migrated as an 84-kDa homodimer under nonreducing conditions. VEGF(121)/rGel bound to purified, immobilized Flk-1, and the binding was competed by VEGF(121). Both VEGF(121)/rGel and VEGF(121) stimulated cellular kinase insert domain receptor (KDR) phosphorylation. The VEGF(121)/rGel fusion construct was highly cytotoxic to endothelial cells overexpressing the KDR/Flk-1 receptor. The IC(50) of the construct on dividing endothelial cells expressing 10(5) or more KDR/Flk-1 receptors per cell was 0.5-1 nM, as compared with 300 nM for rGel itself. Dividing endothelial cells overexpressing KDR were approximately 60-fold more sensitive to VEGF(121)/rGel than were nondividing cells. Endothelial cells overexpressing FLT-1 were not sensitive to the fusion protein. Human melanoma (A-375) or human prostate (PC-3) xenografts treated with the fusion construct demonstrated a reduction in tumor volume to 16% of untreated controls. The fusion construct localized selectively to PC-3 tumor vessels and caused thrombotic damage to tumor vessels with extravasation of red blood cells into the tumor bed. These studies demonstrate the successful use of VEGF(121)/rGel fusion construct for the targeted destruction of tumor vasculature in vivo. 相似文献