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Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
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Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index.  相似文献   
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Partial nephrectomy is the mainstay of treatment for localized kidney cancer. A proportion of patients are upstaged post-operatively to locally advanced di  相似文献   
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Wistar strain adult male and female rats were given 25, 50 and 75% less food than an ad libitum-fed group of rats for 45 d and the effects of food restriction on hepatic drug metabolizing enzymes, microsomal electron transport components, NADPH-dependent lipid peroxidation and glutathione-S-transferase activities were studied. Compared to ad libitum-fed controls, the cytochrome P-450 levels were higher in food restricted male rats, while they were lower in food restricted females. The activities of NADPH cytochrome c reductase were lower in food restricted females than in ad libitum-fed controls. The activities of drug metabolizing enzymes, aminopyrine N-demethylase and acetanilide hydroxylase were higher in food restricted males, whereas in food restricted females these activities were lower than in respective groups fed ad libitum. Microsomal, NADPH-dependent lipid peroxidation was higher in 25 and 50% food restricted females while in 50 and 75% food restricted males it was lower than in ad libitum controls of the same sex. The cytosolic glutathione-S-transferase activities were lower in food restricted rats of both the sexes than in the same sexed controls. Another group of male and female rats were given 75% less food than the ad libitum-fed rats and refed for 3 d prior to killing. Here also, the effects of restriction were different between sexes. It is concluded that hepatic microsomal mixed-function oxidase system (MFOS) is altered due to feed restriction and food restriction followed by refeeding, in a sex-related manner.  相似文献   
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