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11.
Apparent diffusion coefficients in prostate cancer: correlation with molecular markers Ki‐67, HIF‐1α and VEGF 下载免费PDF全文
Teng Ma Shaolin Yang Haiyan Jing Lin Cong Zhixin Cao Zhiling Liu Zhaoqin Huang 《NMR in biomedicine》2018,31(3)
Prostate cancer (PCa) is the second most common cancer in men. The Gleason score (GS) and biomarkers play important roles in the diagnosis and treatment of patients with PCa. The purpose of this study was to investigate the relationship between the apparent diffusion coefficient (ADC) and the molecular markers Ki‐67, hypoxia‐inducible factor‐1α (HIF‐1α) and vascular endothelial growth factor (VEGF) in PCa. Thirty‐nine patients with 39 lesions, who had been diagnosed with PCa, were enrolled in this study. All patients underwent diffusion‐weighted magnetic resonance imaging (DW‐MRI) (b = 800 s/mm2). The expression of Ki‐67, HIF‐1α and VEGF was assessed by immunohistochemistry. Statistical analysis was applied to analyze the association between ADC and prostate‐specific antigen (PSA), GS and the expression of Ki‐67, HIF‐1α and VEGF. The group differences in ADC among different grades of Ki‐67, HIF‐1α and VEGF were also analyzed. The mean ± standard deviation of ADC was (0.76 ± 0.27) × 10?3 mm2/s. ADC correlated negatively with PSA and GS (p < 0.05). The Ki‐67 staining index (SI), HIF‐1α expression and VEGF expression in PCa were correlated inversely with ADC, controlling for age (r = –0.332, p < 0.05; r = ?0.662, p < 0.0005; and r = ?0.714, p < 0.0005, respectively). ADC showed a significant difference among different grades of Ki‐67 (F = 9.164, p = 0.005), HIF‐1α (F = 40.333, p < 0.0005) and VEGF (F = 22.048, p < 0.0005). In conclusion, ADC was correlated with PSA, GS, and Ki‐67, HIF‐1α and VEGF expression in patients with PCa. ADC may be used to evaluate tumor proliferation, hypoxia and angiogenesis in PCa. 相似文献
12.
Lise Vejby Søgaard Franz Schilling Martin A. Janich Marion I. Menzel Jan Henrik Ardenkjær‐Larsen 《NMR in biomedicine》2014,27(5):561-569
The combination of hyperpolarized MRS with diffusion weighting (dw) allows for determination of the apparent diffusion coefficient (ADC), which is indicative of the intra‐ or extracellular localization of the metabolite. Here, a slice‐selective pulsed‐gradient spin echo sequence was implemented to acquire a series of dw spectra from rat muscle in vivo to determine the ADCs of multiple metabolites after a single injection of hyperpolarized [1‐13C]pyruvate. An optimal control optimized universal‐rotation pulse was used for refocusing to minimize signal loss caused by B1 imperfections. Non‐dw spectra were acquired interleaved with the dw spectra and these were used to correct for signal decay during the acquisition as a result of T1 decay, pulse imperfections, flow etc. The data showed that the ADC values for [1‐13C]lactate (0.4–0.7 µm2/ms) and [1‐13C]alanine (0.4–0.9 µm2/ms) were about a factor of two lower than the ADC of [1‐13C]pyruvate (1.1–1.5 µm2/ms). This indicates a more restricted diffusion space for the former two metabolites consistent with lactate and alanine being intracellular. The higher ADC for pyruvate (similar to the proton ADC) reflected that the injected substance was not confined inside the muscle cells but also present extracellular. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
13.
《Patient education and counseling》2022,105(5):1082-1088
ObjectiveTo assess intervention feasibility and acceptability, and compare the effectiveness of the CHOICES Decision Aid (DA) versus the National Cancer Institute (NCI) Cancer Clinical Trials (CCT) website to improve knowledge about CCTs and preparedness to make an informed decision.MethodsOncology patients (n = 101) with a scheduled clinic visit were enrolled and randomized. Decision-making variables were collected at two timepoints. Post-intervention scores were examined via paired t-tests and multivariate regression analyses. Predictors of the magnitudes of the change in scores were examined in multivariable regression analyses.ResultsThe interventions were feasible to implement and acceptable to participants. Both interventions increased objective and subjective knowledge, improved clarity of opinions, and reduced decisional conflict (p-values < 0.01). Improvements in the belief that one could find out about CCTs were observed in the CHOICES DA arm (p < 0.001). Multivariable analyses controlling for educational attainment showed no significant differences in the magnitude of change in outcome variables between intervention arms, but did find that improvements in some variables in the NCI arm – but not CHOICES DA arm – were associated with previous educational attainment.ConclusionsInterventions were feasible to implement and acceptable. Improvements in knowledge and decision-making outcomes were observed in both arms, supporting the view that interventions to improve CCT decision making are effective and feasible. Our results suggest that the CHOICES DA may be more effective than an informational website in improving decision-making outcomes regardless of participants’ educational attainment.Practice implicationsCCT resources should support informed decision-making among all cancer survivors, regardless of educational attainment. 相似文献
14.
Background/Objectives
Due to its rarity, epidermoid cyst in intrapancreatic accessory spleen (ECIPAS) is still a diagnostic dilemma during clinical practice. The aim of this review was to summarize the epidemiologic features and management of ECIPAS.Methods
MEDLINE and EMBASE were searched for English articles reporting on ECIPAS up to April 30th, 2018 following the methodology suggested by the PRISMA guidelines. Categorical variables were reported as frequency and percentage. Continuous variables were reported as median (range).Results
A total of 56 patients from 47 full articles were included for the final data synthesis. More than half of the ECIPASs (59%) were found incidentally. The female/male ratio was 1.33. ECIPAS is typically a single mono-/multi-lobular cystic lesions in the pancreatic tail with thickened cystic wall or various amount of solid component which had identical density/signal to the spleen on imaging examinations. The cyst is filled with serous or non-serous fluid. Recognition of the surrounding ectopic splenic tissue is the key point to diagnose ECIPAS. However, no preoperative examination was able to make a definite diagnosis. Almost all the patients (96%) received surgical treatment, due to the suspicion of pancreatic malignant or potentially malignant cystic tumor, especially mucinous cystic neoplasm (MCN).Conclusions
Although seldom encountered, ECIPAS should be considered as a differential diagnosis for pancreatic cystic lesions, especially when solid component was detected. As a benign disease, unnecessary surgery should be avoided. Because it is difficult to make a definite diagnosis preoperatively by one single examination, multiple modalities may be required. 相似文献15.
模数转换器(Analog-to-Digital Converter,ADC)是片上集成系统的关键部件,通过对逐次逼近逻辑电路和三值逻辑原理的研究,提出了一种基于碳纳米场效应晶体管(Carbon Nanotube Field Effect Transistor,CNFET)的三值逐次逼近ADC设计方案。该方案首先控制三值电容阵列的底板电压,逐次逼近其模拟量值,产生由高位到低位的二值信号,然后由编码器将二值转换为三值信号,完成整个转换过程,最后实验证明了所设计的电路逻辑功能正确,并具有明显的高速、低功耗特性。 相似文献
16.
Rishabh Kumar Prachi Kala Geeta S. Narayanan Bhaskar Vishwanathan Sowmya Narayanan Sanjeet Mandal Arpitha Rao Gangadharappa Gowda 《Brachytherapy》2021,20(1):112-117
PURPOSEImage-guided adaptive brachytherapy (IGABT) recently has shown excellent clinical outcomes with superior local control and less toxicity. For IGABT, T2W (T2-weighted) MRI is the gold standard. However, studies have shown that target delineation with the same results in uncertainties, poor interobserver variabilities, and low conformity indices for high-risk clinical target volume contours. In this study, we investigate the role of diffusion-weighted imaging–derived apparent diffusion coefficient (ADC) maps to aid in IGABT. We also evaluated ADC from the baseline to brachytherapy.Methods and MaterialsThirty selected patients were enrolled for this study, and two MRIs were taken at diagnosis and before brachytherapy. Patients were divided into two groups, Group 1 being patients with parametrial involvement before external beam radiotherapy and no parametrial involvement before brachytherapy. Group 2 included patients with parametrial involvement before external beam radiotherapy and persistent parametrial involvement before brachytherapy. ADC was measured at the center, edge, and 1 cm from the edge.ResultsThe measured ADC increased from diagnosis to brachytherapy, and this increase was more for the patients in Group 1 than in Group 2. The mean TDadc (diagnosis ADC, center), TEadc (tumor edge ADC diagnosis), and T1cmDadc (1 cm from edge at diagnosis) were 0.884, 1.45, and 1.9 × 10?3 mm2/s, respectively. The TBadc (ADC at brachytherapy, center), TEBadc (tumor edge ADC at brachytherapy), and TE1cmBadc (1 cm from edge brachytherapy) were 1.2, 1.8, and 2.3 × 10?3 mm2/s, respectively, p-value <0.00001. No abnormal ADC was present outside the high-risk clinical target volume contours.ConclusionMRI-based IGABT using T2W imaging essentially covers all functionally abnormal zones at brachytherapy. Diffusion-weighted imaging, along with ADC maps, should only be used as a supplement for target delineation. 相似文献
17.
Marieke de Vries Angela Fagerlin Holly O. Witteman Laura D. Scherer 《Patient education and counseling》2013
Objective
To review the strengths and weaknesses of deliberative and intuitive processes in the context of patient decision support and to discuss implications for decision aid (DA) design.Methods
Conceptual review of the strengths and weaknesses of intuitive and analytical decision making and applying these findings to the practice of DA design.Results
DAs combine several important goals: providing information, helping to clarify treatment related values, supporting preference construction processes, and facilitating more active engagement in decision making. Many DAs encourage patients to approach a decision analytically, without solid theoretical or empirical grounding for this approach. Existing research in other domains suggests that both intuition and deliberation may support decision making. We discuss implications for patient decision support and challenge researchers to determine when combining these processes leads to better outcomes.Conclusions
Intuitive and analytical decision processes may have complementary effects in achieving the desired outcomes of patient decision support.Practice implications
DA developers should be aware that tools solely targeted at supporting deliberation may limit DA effectiveness and harm preference construction processes. Patients may be better served by combined strategies that draw on the strengths and minimize the weaknesses of both deliberative and intuitive processes. 相似文献18.
Shannon L. Arntfield Kristen Slesar Jennifer Dickson Rita Charon 《Patient education and counseling》2013
Objective
This study sought to explore the perceived influence of narrative medicine training on clinical skill development of fourth-year medical students, focusing on competencies mandated by ACGME and the RCPSC in areas of communication, collaboration, and professionalism.Methods
Using grounded-theory, three methods of data collection were used to query twelve medical students participating in a one-month narrative medicine elective regarding the process of training and the influence on clinical skills. Iterative thematic analysis and data triangulation occurred.Results
Response rate was 91% (survey), 50% (focus group) and 25% (follow-up). Five major findings emerged. Students perceive that they: develop and improve specific communication skills; enhance their capacity to collaborate, empathize, and be patient-centered; develop personally and professionally through reflection. They report that the pedagogical approach used in narrative training is critical to its dividends but misunderstood and perceived as counter-culture.Conclusion/Practice implications
Participating medical students reported that they perceived narrative medicine to be an important, effective, but counter-culture means of enhancing communication, collaboration, and professional development. The authors contend that these skills are integral to medical practice, consistent with core competencies mandated by the ACGME/RCPSC, and difficult to teach. Future research must explore sequelae of training on actual clinical performance. 相似文献19.
20.