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951.
Wonseok Kang Seung Up Kim Sang Hoon Ahn 《World journal of gastroenterology : WJG》2014,20(10):2613-2623
In patients with chronic liver diseases,identification of significant liver fibrosis and cirrhosis is essential for determining treatment strategies,assessing therapeutic response,and stratifying long-term prognosis.Although liver biopsy remains the reference standard for evaluating the extent of liver fibrosis in patients with chronic liver diseases,several non-invasive methods have been developed as alternatives to liver biopsies.Some of these non-invasive methods have demonstrated clinical accuracy for diagnosing significant fibrosis or cirrhosis in many cross-sectional studies with the histological fibrosis stage as a reference standard.However,non-invasive methods cannot be fully validated through cross-sectional studies since liver biopsy is not a perfect surrogate endpoint marker.Accordingly,recent studies have focused on assessing the performance of non-invasive methods through longterm,longitudinal,follow-up studies with solid clinical endpoints related to advanced stages of liver fibrosis and cirrhosis.As a result,current view is that these alternative methods can independently predict future cirrhosis-related complications,such as hepatic decompensation,liver failure,hepatocellular carcinoma,or liver-related death.The clinical role of non-invasive models seems to be shifting from a simple tool for predicting the extent of fibrosis to a surveillance tool for predicting future liver-related events.In this article,we will summarize recent longitudinal studies of non-invasive methods for predicting forthcoming complications related to liver cirrhosis and discuss the clinical value of currently available non-invasive methods based on evidence from the literature. 相似文献
952.
Liver stiffness measurement(LSM)is a good,but still limited tool to noninvasively assess complications and prognosis in patients with advanced liver disease.This review aims to consider the role of LSM for the diagnosis of portal hypertension-related complications and for assessment of prognosis in cirrhotic patients,and to highlight the drawbacks as well as some alternatives for improving the performance.Hence,this field is far from being closed,and deserves more attention.There is still a place for more carefully designed studies to find new,innovative and reliable approaches. 相似文献
953.
目的 探索miR-199b-5p在骨肉瘤中的预测和诊断作用。方法 运用RT-PCR方法检测骨肉瘤患者组织中miR-199b-5p和DRAM的表达水平;利用生物信息学预测工具预测miR-199b-5p的靶基因;分析DRAM与miR-199b-5p的表达关系。结果 miR-199b-5p在组织中有表达,和癌旁正常组织相比,肿瘤组织中的miR-199b-5p表达水平显著升高(P < 0.05);miR-199b-5p与患者的性别、发病年龄、病变部位、肿瘤分型和分期无明显关系(P > 0.05)。研究还发现DRAM在各种组织中均有表达,而DRAM mRNA表达在两者中无明显差异,DRAM与miR-199b-5p呈负相关的表达关系。结论 本研究表明miR-199b-5p可以作为骨肉瘤一个诊断标志物,而DRAM可能是miR-199b-5p的调控靶基因。 相似文献
954.
M.J. Rutten J.H.L. Boldingh E. Schuit H. Trum W. van Driel B.W.J. Mol G.G. Kenter M.R. Buist 《Gynecologic oncology》2014
Objective
Predicting survival of patients with epithelial ovarian cancer (EOC) is based on prognosis of the population. Combining prognostic factors could facilitate survival prediction on the level of the individual patient. The aim of this study was to develop a prognostic model to predict five-year disease specific survival in patients with EOC, and to evaluate whether this would add to prediction based on prognosis of the population.Patients and methods
A retrospective cohort study was performed of all EOC patients treated with primary debulking and adjuvant chemotherapy or neo-adjuvant chemotherapy and interval debulking surgery in three gynaecological-oncologic centres between 1998 and 2010. Primary outcome was 5-year disease-specific survival. We developed a Cox proportional hazard model using the LASSO-method to select the best combination of characteristics from 12 potential predictors and to correct for overfitting. Performance of the model was expressed as calibration and discrimination (c-statistic). A nomogram was developed to increase the clinical applicability of the model.Results
Of 840 patients with EOC 462 (55%) died within 5 years due to the disease. A combination of FIGO stage, residual tumour after surgery, primary or interval surgery, histology, performance status, age, amount of ascites and a family history suggestive of breast/ovarian cancer best predicted 5-year survival. The final model showed accurate calibration and the c-statistic was 0.71 (95% CI 0.69–0.74).Conclusions
Five-year survival in all stage EOC patients can be predicted accurately using available characteristics. After external validation the model can be used for counselling of patients. 相似文献955.
Bin Wu Juanzi Shi Wanqiu Zhao Suzhen Lu Marta Silva Timothy J. Gelety 《Journal of assisted reproduction and genetics》2014,31(10):1323-1330
Purpose
Evaluating the failed IVF cycle often provides useful prognostic information. Before undergoing another attempt, patients experiencing an unsuccessful IVF cycle frequently request information about the probability of future success. Here, we introduced the concept of reproducibility and formulae to predict the next IVF cycle outcome.Methods
The experimental design was based on the retrospective review of IVF cycle data from 2006 to 2013 in two different IVF centers and statistical analysis. The reproducibility coefficients (r) of IVF traits including number of oocytes retrieved, oocyte maturity, fertilization, embryo quality and pregnancy were estimated using the interclass correlation coefficient between the repeated IVF cycle measurements for the same patient by variance component analysis. The formulae were designed to predict next IVF cycle outcome.Results
The number of oocytes retrieved from patients and their fertilization rate had the highest reproducibility coefficients (r = 0.81 ~ 0.84), which indicated a very close correlation between the first retrieval cycle and subsequent IVF cycles. Oocyte maturity and number of top quality embryos had middle level reproducibility (r = 0.38 ~ 0.76) and pregnancy rate had a relative lower reproducibility (r = 0.23 ~ 0.27). Based on these parameters, the next outcome for these IVF traits might be accurately predicted by the designed formulae.Conclusions
The introduction of the concept of reproducibility to our human IVF program allows us to predict future IVF cycle outcomes. The traits of oocyte numbers retrieved, oocyte maturity, fertilization, and top quality embryos had higher or middle reproducibility, which provides a basis for accurate prediction of future IVF outcomes. Based on this prediction, physicians may counsel their patients or change patient’s stimulation plans, and laboratory embryologists may improve their IVF techniques accordingly. 相似文献956.
Walsh JM McAuliffe FM 《European journal of obstetrics, gynecology, and reproductive biology》2012,162(2):125-130
Fetal macrosomia is associated with significant maternal and neonatal morbidity. In the long term, infants who are large for gestational age are more likely than other infants to be obese in childhood, adolescence and early adulthood, and are inherently at higher risk of cardiovascular and metabolic complications in adulthood. With over one billion adults in the world now overweight and more than 600 million clinically obese, preventing the vicious cycle effect of fetal macrosomia and childhood obesity is an increasingly pertinent issue. Fetal growth is determined by a complex interplay of various genetic and environmental influences. Consequently the prediction of pregnancies at risk of pathological overgrowth is difficult. Many risk factors for fetal macrosomia, such as maternal obesity and advanced maternal age, are also conversely associated with intrauterine growth restriction. Sonographic detection of fetal macrosomia is notoriously fraught with difficulties, with dozens of formulas for estimated fetal weight proposed but few with sufficient sensitivity to alter clinical practice. This calls into question policies of elective delivery based on projected estimated fetal weight cut-offs alone. More recently the identification of markers of fetal adiposity and maternal serum biomarkers are being investigated to improve the antenatal detection of the large for gestational age fetus. Prevention of fetal macrosomia is entirely dependent upon correct identification of those at risk. Maternal weight, gestational weight gain and glycaemic control are the risk factors for fetal macrosomia that are most amenable to intervention, and have potential maternal health benefits beyond pregnancy and childbirth. The ideal method of optimising maternal weight and glucose homeostasis is yet to be elucidated, though a number of promising advances are recently being reported. In this review we outline the contemporary evidence for the prediction and prevention of fetal macrosomia, which is indeed a contemporary dilemma. 相似文献
957.
Ada G.T.M. Egelmeer E. Rios Velazquez Jos M.A. de JongCary Oberije Yasmyne GeussensSandra Nuyts Bernd KremerDerek Rietveld C. René LeemansMonique C. de Jong Coen RaschFrank Hoebers Jarrod HomerNick Slevin Catharine WestPhilippe Lambin 《Radiotherapy and oncology》2011,100(1):108-115
Introduction
To advise laryngeal carcinoma patients on the most appropriate form of treatment, a tool to predict survival and local control is needed.Materials and methods
We performed a population-based cohort study on 994 laryngeal carcinoma patients, treated with RT from 1977 until 2008. Two nomograms were developed and validated. Performance of the models is expressed as the Area Under the Curve (AUC).Results
Unfavorable prognostic factors for overall survival were low hemoglobin level, male sex, high T-status, nodal involvement, older age, lower EQD2T (total radiation dose corrected for fraction dose and overall treatment time), and non-glottic tumor. All factors except tumor location were prognostic for local control. The AUCs were 0.73 for overall survival and 0.67 for local control. External validation of the survival model yielded AUCs of 0.68, 0.74, 0.76 and 0.71 for the Leuven (n = 109), the VU Amsterdam (n = 178), the Manchester (n = 403) and the NKI cohort (n = 205), respectively, while the validation procedure for the local control model resulted in AUCs of 0.70, 0.71, 0.72 and 0.62. The resulting nomograms were made available on the website www.predictcancer.org.Conclusions
For patients with a laryngeal carcinoma treated with RT alone, we have developed visual, easy-to-use nomograms for the prediction of overall survival and primary local control. These models have been successfully validated in four external centers. 相似文献958.
959.
近年来中医运气学说受到了普遍重视,许多学者试图以运气学说来预测疫病的流行,或以其指导对疫病的预防与治疗。文章在对相关研究文献分析的基础上,认为以运气推演的气候模式变化预测疫病的流行,是缺乏充分科学依据的,其结论也缺乏科学性。 相似文献
960.
Although measurement of the radiofrequency (RF) exposure can today be performed with personal exposure meters, this approach would be very expensive and time-consuming for large studies, and long term measurements would require considerable commitment of the study participants. Thus, there is a need for validated exposure assessment methods that do not require individual measurements for each study participant. Among the potential predictors, one of the most amenable to being recorded adequately is the day of the week. Drawing upon an existing population-based study, our goal was therefore to assess variability of individual RF exposure across days of the week. The random sample consisted of 34 people who were supplied with a personal exposure meter for seven consecutive days, and kept a time–location–activity diary. A total of 225,414 electric field strength measurements were recorded in 12 different RF bands. Summary statistics were calculated with the robust regression on order statistics method. We found evidence for statistically significant variability of individual RF exposure across days of the week, though the relative magnitude of the differences observed was small. Larger studies are needed to validate these results and determine whether day of the week is an important determinant for inclusion in individual RF exposure prediction models that remain urgently needed to conduct epidemiological studies on potential health effects. 相似文献