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51.
PURPOSE: We assessed the usefulness of and indications for endoscopic treatment of vesicoureteral reflux in myelodysplasia patients. MATERIALS AND METHODS: A total of 26 patients treated with intermittent catheterization was divided into 11 (16 ureters) with and 15 without vesicoureteral reflux. In 9 patients (13 ureters) endoscopic correction was performed with 3% atelo-collagen and without anesthesia at the outpatient clinic. In each ureter we obtained the sum of scores for 4 risk factors for upper urinary tract deterioration: bladder compliance less than 10 ml./cm. water, grade 2 to 3 bladder deformity, detrusor-sphincter dyssynergia and urethral closure pressure 50 cm. water or greater. RESULTS: No reflux was demonstrated immediately after the initial collagen injection but cystography 3 to 6 months later showed recurrent reflux in 5 ureters (38%). Repeat injection cured the reflux, with results persisting for an average of 17 months. Mean risk factor score for patients without vesicoureteral reflux was significantly lower than that for patients with reflux. In patients treated with intermittent catheterization and anticholinergic agents the mean score for ureters with an increased or unchanged reflux grade was significantly greater than for those with a decreased grade. CONCLUSIONS: Endoscopic treatment of reflux appears to be safe and useful in patients with myelodysplasia. The treatment is preferable in those with high risk factor scores due to the possibility of increased reflux grade in such patients.  相似文献   
52.
A side-chain liquid-crystalline polymer (LCP) was synthesized by the addition of the mesogenic monomer to poly(methyl siloxane) in presence of a Pt-catalyst. When an aqueous solution of 10wt% ethanol was permeated through a LCP membrane by pervaporation at various temperatures, the permeation rate increased with increasing temperature and drastically changed at glass-nematic (Tg) and nematic-isotropic (TNI) transition temperatures of the LCP membrane. The LCP membrane exhibited the waterpermselectivity in the glassy and liquid-crystalline states. The ethanol concentration in the permeate increased with increasing permeation temperature and the LCP membrane changed from the waterpermselectivity to the ethanol-permselectivity around TNI. These results suggested that the permselectivity was influenced by the change of the LCP membrane structure, that is, its state transformation. It was found that a balance of the orientation of mesogenic groups and flexibility of siloxane chains is very important for the permeability and selectivity.  相似文献   
53.
54.
This paper proposes bootstrap robust estimation methods for the Weibull parameters; it applies bootstrap estimators of order statistics to the parametric estimation procedure. Estimates of the Weibull parameters are equivalent to the estimates using the extreme value distribution. Therefore, the bootstrap estimators of order statistics for the parameters of the extreme value distribution are examined. Accuracy and robustness for outliers are examined by Monte Carlo experiments which indicate adequate efficiency of the proposed reliability estimators for data with some outliers  相似文献   
55.
Temperature dependences of the soft phonon frequency and the damping constant in Tris-Sarcosine Calcium Chloride (TSCC) single crystal have been investigated between 5K and 100K by using a Fourier-transform far-infrared spectrometer. It has been observed that the soft phonon frequency decreases gradually and the damping constant increases as the transition temperature is approached from below The damping constant varies from 7cm-1 a 90K to less than 0.5cm-1 at 5K. It has been found that the damping constant is approximately proportional to temperature below about 60K.  相似文献   
56.
A computer program system was developed to predict carbohydrate-bindingsites on three-dimensional (3D) protein structures. The programssearch for binding sites by referring to the empirical rulesderived from the known 3D structures of carbohydrate–proteincomplexes. A total of 80 non-redundant carbohydrate–proteincomplex structures were selected from the Protein Data Bankfor the empirical rule construction. The performance of theprediction system was tested on 50 known complex structuresto determine whether the system could detect the known bindingsites. The known monosaccharide-binding sites were detectedamong the best three predictions in 59% of the cases, whichcovered 69% of the polysaccharide-binding sites in the targetproteins, when the performance was evaluated by the overlapbetween residue patches of predicted and known binding sites. Received April 24, 2003; revised June 2, 2003; accepted June 10, 2003.  相似文献   
57.
Criteria for evaluating flexibility of a generation mix are presented, and an efficient computational algorithm for determining a flexible generation mix considering uncertainties in the power system expansion planning is developed. The flexible generation mix problem is formulated as a multiobjective optimization problem and solved by the dynamic programming technique in which type of generation plant is selected as a stage and generation capacity is selected as a state. The proposed method can treat easily not only the uncertainties but also many constraints of generation planning such as integer solutions of generation capacities, reliability constraints, and so on. The effectiveness and feasibility of the proposed method are demonstrated on a typical power system model  相似文献   
58.
The chemiluminescence of the Cypridina luciferin analogue, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-a]pyrazin++ +-3-one (MCLA) was observed at 462 nm in the presence of horseradish peroxidase (HRP) and the total spectrum of light emitted was found to depend linearly on HRP concentration. Methods for the determination of HRP concentration using the chemiluminescence was investigated. HRP could be detected in the range from 100 pmol/L to 100 nmol/L under the optimum condition, H2O2 (10 mmol/L) and MCLA (10 mumol/L) at pH 5.8.  相似文献   
59.
Oxide semiconductors have been examined to develop NOx sensors for exhaust monitoring. Titania doped with trivalent elements, such as Al3+, Sc3+, Ga3+ or In3+, has a good sensitivity and selectivity to NO between 450 and 550 °C, and shows rapid response. A sensor probe for monitoring exhaust NOx has been fabricated. Many kinds of interference gases, such as C3H6, CO and SO2, have been found to have only a slight influence on the sensor response to NO. The influence of O2 and H2O is also negligible, except for the cases of 0% H2O and fuel-rich conditions. In accordance with these results, the sensor probe operates satisfactority in the exhaust gas of various combustion conditions without interference from the various kinds of gas species in the exhaust gases.  相似文献   
60.
Holographic projection is for laser displays and has the merits of being aberration free, producing high‐contrast images, having the ability of color reconstruction with one spatial light modulator, and so on. In this paper, we propose a zoomable holographic projection without using a zoom lens and verify the proposed method by using numerical simulation. Although such a system can be readily realized to use the features of holography, which is capable of recording a large image exceeding the hologram size, the required calculation is very time consuming. For acceleration, we used shifted Fresnel diffraction for setting different sampling rates on a hologram and projected image. The proposed method can project any zoom‐in and zoom‐out image between zeroth‐order and first‐order lights, and the processing time and required memory for the zoom are constant.  相似文献   
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