631 research outputs found
Prediction of large esophageal varices in cirrhotic patients using classification and regression tree analysis
OBJECTIVES: Recent guidelines recommend that all cirrhotic patients should undergo endoscopic screening for esophageal varices. That identifying cirrhotic patients with esophageal varices by noninvasive predictors would allow for the restriction of the performance of endoscopy to patients with a high risk of having varices. This study aimed to develop a decision model based on classification and regression tree analysis for the prediction of large esophageal varices in cirrhotic patients. METHODS: 309 cirrhotic patients (training sample, 187 patients; test sample 122 patients) were included. Within the training sample, the classification and regression tree analysis was used to identify predictors and prediction model of large esophageal varices. The prediction model was then further evaluated in the test sample and different Child-Pugh classes. RESULTS: The prevalence of large esophageal varices in cirrhotic patients was 50.8%. A tree model that was consisted of spleen width, portal vein diameter and prothrombin time was developed by classification and regression tree analysis achieved a diagnostic accuracy of 84% for prediction of large esophageal varices. When reconstructed into two groups, the rate of varices was 83.2% for high-risk group and 15.2% for low-risk group. Accuracy of the tree model was maintained in the test sample and different Child-Pugh classes. CONCLUSIONS: A decision tree model that consists of spleen width, portal vein diameter and prothrombin time may be useful for prediction of large esophageal varices in cirrhotic patient
Distribution of Spectral Lags in Gamma Ray Bursts
Using the data acquired in the Time To Spill (TTS) mode for long gamma-ray
bursts (GRBs) collected by the Burst and Transient Source Experiment on board
the Compton Gamma Ray Observatory (BATSE/CGRO), we have carefully measured
spectral lags in time between the low (25-55 keV) and high (110-320 keV) energy
bands of individual pulses contained in 64 multi-peak GRBs. We find that the
temporal lead by higher-energy gamma-ray photons (i.e., positive lags) is the
norm in this selected sample set of long GRBs. While relatively few in number,
some pulses of several long GRBs do show negative lags. This distribution of
spectral lags in long GRBs is in contrast to that in short GRBs. This apparent
difference poses challenges and constraints on the physical mechanism(s) of
producing long and short GRBs. The relation between the pulse peak count rates
and the spectral lags is also examined. Observationally, there seems to be no
clear evidence for systematic spectral lag-luminosity connection for pulses
within a given long GRB.Comment: 20 pages, 4 figure
Expanded CURB-65: A new score system predicts severity of community-acquired pneumonia with superior efficiency
Aim of this study was to develop a new simpler and more effective severity score for communityacquired pneumonia (CAP) patients. A total of 1640 consecutive hospitalized CAP patients in Second
Affiliated Hospital of Zhejiang University were included. The effectiveness of different pneumonia
severity scores to predict mortality was compared, and the performance of the new score was validated
on an external cohort of 1164 patients with pneumonia admitted to a teaching hospital in Italy.
Using ageâ„â65 years, LDH>230u/L, albumin<3.5g/dL, platelet count<100Ă109/L, confusion,
urea>7mmol/L, respiratory rateâ„30/min, low blood pressure, we assembled a new severity score
named as expanded-CURB-65. The 30-day mortality and length of stay were increased along with
increased risk score. The AUCs in the prediction of 30-day mortality in the main cohort were 0.826
(95%CI, 0.807â0.844), 0.801 (95%CI, 0.781â0.820), 0.756 (95%CI, 0.735â0.777), 0.793 (95%CI,
0.773â0.813) and 0.759 (95%CI, 0.737â0.779) for the expanded-CURB-65, PSI, CURB-65, SMART-COP
and A-DROP, respectively. The performance of this bedside score was confirmed in CAP patients of
the validation cohort although calibration was not successful in patients with health care-associated
pneumonia (HCAP). The expanded CURB-65 is objective, simpler and more accurate scoring system for
evaluation of CAP severity, and the predictive efficiency was better than other score systems
Effect of Scrophularia ningpoensis extract on diabetes in rats
Purpose: To investigate the effect of Scrophularia ningpoensis extract (SNE) on streptozotocin-induced diabetic rats.Methods: SNE was obtained by steeping the dried Scrophularia ningpoensis in water at 60 oC three times, each for 1 h, before first drying in an oven at 100 oC and then freeze-drying the last extract thus obtained. Diabetic rats were prepared by a single intraperitoneal injection of a freshly prepared solution of streptozotocin (50 mg/kg). The rats were randomly divided into 6 groups of ten rats each: negative control group, control group, reference group (glibenclamide1 mg/kgbody weight) as well as SNE groups, (50, 100 and 200 mg/kg). Blood glucose and plasma insulin levels were evaluated in order to determine antihyperglycemic effect. Oxidative stress was evaluated in liver and kidney by antioxidant markers, viz, lipid peroxidation (LPO), superoxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GPx) and catalase (CAT); blood serum levels of creatinine and urea were determined in both diabetic control and treated rats.Results: Compared with diabetic rats, oral administration of SNE at a concentration of 200 mg/kg daily for 30 days showed a significant decrease in fasting blood glucose to 120.21 ± 3.37 mg/dL (p < 0.05) and increased insulin level to 13.31 ± 0.67 uU/mL (p < 0.05). Furthermore, it significantly reduced biochemical parameters (serum creatinine, 0.86 ± 0.24 mg/dL, p < 0.05) and serum urea (41.86 ± 1.59 mg/dL, p < 0.05).Conclusion: The results suggest that SNE may effectively normalize impaired antioxidant status in streptozotocin-induced diabetes in a dose-dependent manner. SNE has a protective effect against lipid peroxidation by scavenging free radicals and is thus capable of reducing the risk of diabetic complications.Keywords: Scrophularia ningpoensis, Diabetic, Antihyperglycemic, Antioxidant Oxidative stress, Fasting blood glucos
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