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991.
Alpha-feto-protein (AFP) is the most popular tumor marker for hepatocellular carcinoma (HCC). It is used in diagnosis and follow up of cases by estimating its rise in the serum. The aim of this work is to study the value of estimating AFP in ascitic fluid of HCC patients with ascites. This work is a case control study on 32 patients, including 22 cases with ascites and HCC and 10 control group with ascites due to liver cirrhosis without HCC. The level of AFP was estimated in serum and in ascitic fluid by Radio-immuno assay RIA. The serum ascites albumin gradient (SAAG) was assessed by measuring albumin in all samples using bromocresole green dye binding. Guided aspiration liver biopsy and ascitic fluid cytology was done, stained with H & E. It was found that, AFP level in serum was elevated in 72.7% of HCC patients, and in ascitic fluid was elevated 63.6% HCC patients. Also, there was a highly significant, direct positive correlation between elevation of AFP in serum and in ascitic fluid (r = 0.778). No elevation of AFP in serum and in ascitic fluid was detected in control group. Ascitic fluid cytology showed malignant cells in one case only. SAAG was significantly lower in the HCC group 0.83 gm/dl than the control group 2.43 gm/dl (p-value < 0.001). Elevation of AFP in ascitic fluid is of high importance in evaluation of HCC, and is as significant as serum and runs parallel to it. Estimation of AFP in ascitic fluid is much more significant in evaluation of HCC cases than ascitic fluid cytology.  相似文献   
992.
This paper is concerned with Cylindrical Wire Electrical Discharge Turning processes being especially developed for difficult to machine materials. First, the effects of the machining parameters power, voltage, pulse off time, and spindle rotation rate on the machining performance, which comprises the material removal rate, the surface roughness, and the roundness, was studied. The machining parameters were evaluated by Taguchi's method. In particular, an L9(34) standard orthogonal array was employed as experimental design while determining the influence on the machining performance using the analysis of variance technique. In a second step, an optimisation of the machining parameters was sought using signal to noise ratio analysis. Therefore, the response surface methodology was determined in a regression analysis, which was used to model the influence of the parameters on the performance. Final experiments with a sophisticated home-made rotary spindle allowed the quantification of the effectiveness of the proposed method.  相似文献   
993.
Optimal major and minimal maintenance policies for deteriorating systems   总被引:7,自引:2,他引:5  
We present a maintenance model for a multi-state semi-Markovian deteriorating system. Our model allows one of three maintenance decisions (do-nothing, minimal maintenance or replacement) to be taken at each state of the system. We use control limit policy and the policy-iteration algorithm to find the optimal maintenance policies that minimizes the expected long-run cost rate of the system. Numerical examples are given to illustrate the proposed policies.  相似文献   
994.
This paper presents the results of a two-phase experimental program investigating the punching shear behavior of fiber reinforced polymer reinforced concrete (FRP RC) flat slabs with and without carbon fiber reinforced polymer (CFRP) shear reinforcement. In the first phase, problems of bond slip and crack localization were identified. Decreasing the flexural bar spacing in the second phase successfully eliminated those problems and resulted in punching shear failure of the slabs. However, CFRP shear reinforcement was found to be inefficient in enhancing significantly the slab capacity due to its brittleness. A model, which accurately predicts the punching shear capacity of FRP RC slabs without shear reinforcement, is proposed and verified. For slabs with FRP shear reinforcement, it is proposed that the concrete shear resistance is reduced, but a strain limit of 0.0045 is recommended as maximum strain for the reinforcement. Comparisons of the slab capacities with ACI 318-95, ACI 440-98, and BS 8110 punching shear code equations, modified to incorporate FRP reinforcement, show either overestimated or conservative results.  相似文献   
995.
Sludge treatment using reed beds is more attractive in the Gaza Strip than traditional sludge drying beds. Sludges having solids contents of 1–2% can be applied to reed beds at a loading of 40 cm/m2 every 2 weeks. The infiltration rate for a reed bed system is high, and the evapotranspiration rate is typically 170% of pan evaporation. The cost of sludge treatment using reed beds is 0.34 US$/m3 compared with 1.01 US$/m3 for treatment using conventional drying beds. This paper presents the results of using reed beds for sludge treatment in the Gaza Strip for 3 years.  相似文献   
996.
Type I diabetes is described by the destruction of the insulin‐producing beta‐cells in the pancreas. Hence, exogenous insulin administration is necessary for Type I diabetes patients. In this study, to estimate the states that are not directly available from the Bergman minimal model a high‐order sliding mode observer is proposed. Then fractional calculus is combined with sliding mode control (SMC) for blood glucose regulation to create more robustness performance and make more degree of freedom and flexibility for the proposed method. Then an adaptive fractional‐order SMC is proposed. The adaptive SMC protect controller against disturbance and uncertainties while the fractional calculus provides robust performance. Numerical simulation verifies that the proposed controllers have better performance in the presence of disturbance and uncertainties without chattering.Inspec keywords: variable structure systems, biochemistry, blood, robust control, medical control systems, observers, sugar, diseases, calculus, adaptive control, cellular biophysicsOther keywords: fractional‐order SMC, adaptive SMC, fractional calculus, robust performance, adaptive fractional‐order blood glucose regulator, insulin‐producing beta‐cells, exogenous insulin administration, diabetes patients, Bergman minimal model, mode control, blood glucose regulation, pancreas, type I diabetes, state estimation, high‐order sliding mode observer, sliding mode control, degree of freedom, numerical simulation  相似文献   
997.
Concurrency constructs are widely used when developing complex software such as real-time, networking and multithreaded client–server applications. Consequently, testing a program, which includes concurrency constructs is a very elaborate and complex process. In this work, we first identify the different classes of synchronization anomalies that may occur in concurrent Java programs. We then consider testing concurrent Java programs against synchronization anomalies using dynamic data flow analysis techniques. Moreover, we show how the data flow analysis technique can be extended to detect such anomalies.  相似文献   
998.
999.
1000.
A highly efficient stereoselective method for the synthesis of functionalized spirooxindole derivatives with four contiguous stereogenic centers, including two adjacent quaternary stereogenic centers, was realized through an organocatalytic tandem Michael–Michael reaction. By employing a quinidine‐derived thiourea organocatalyst, the reaction between (E)‐2‐cyano‐2‐(2‐oxo‐1‐tritylindolin‐3‐ylidene)acetates and (E)‐1‐alkyl‐6‐nitro‐hex‐2‐en‐1‐ones yields the desired spirooxindole products in good yields (up to 90%) and with excellent stereoselectivities (up to 95:5 dr and 98% ee).

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