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11.
对菱镁矿在固体燃料燃烧过程中的固硫特性进行了理论研究,所得结论对进一步将菱镁矿作为固体燃料燃烧过程中的固硫剂具有非常重要的意义。 相似文献
12.
BACKGROUND: To determine the best cutoff values of aspartate aminotransferase (AST) and alanine amino-transferase (ALT) in detecting viral hepatitis C infection among patients of continuous ambulatory peritoneal dialysis (CAPD). METHODS: 90 (44 male and 46 female) CAPD patients and 526 adult controls (266 male, 260 female) were enrolled. Serum AST and ALT were measured by an auto-analyser monthly. Serum HBsAg was examined using a RIA method and anti-HCV by an second-generation EIA method. The best cutoff values of AST and ALT for detecting viral hepatitis were obtained from the ROC (receiver-operating characteristic) curve. RESULTS: The prevalence of anti-HCV(+) was significantly higher in CAPD patients (16.7%) than in normal controls (4.9%), while that of HBsAg(+) was similar in both groups. CAPD patients had significantly lower levels of serum aminotransferases compared to normal controls. Mean AST were 23.8 IU/l in normal control and 18.8 IU/l in the CAPD patients (P < 0.001). Mean ALT were 21.9 IU/l in normal controls and 15.3 IU/l in the CAPD patients (P < 0.001). CAPD patients with HCV infection had higher serum AST and ALT levels than those without. However, HBV infection did not cause significant serum aminotransferase elevation in patients. The conventional cutoff values of AST (40 IU/l) and ALT (40 IU/l) for detecting viral hepatitis yielded only a sensitivity of 27.3 and 18.2% respectively; on the contrary, our revised cutoff values of AST (24 IU/l) and ALT (17 IU/l) had better sensitivities (AST, 72.7%; ALT, 63.6%). For serial aminotransferase values, the sensitivity of AST and ALT for detecting HCV were 36.4 and 27.3% by conventional criteria, and were both 81.8%, by our newly revised criteria. CONCLUSIONS: Serum aminotransferase cutoff values should be modified for screening viral hepatitis in a CAPD population. Our new cutoff criteria had important clinical implications in providing benefits of earlier detection and possible prevention from chronic hepatic deteriorations. 相似文献
13.
BM Chen LY Chan SM Wang MF Wu JW Chern SR Roffler 《Canadian Metallurgical Quarterly》1997,73(3):392-402
We examined the in vivo efficacy of targeting beta-glucuronidase (betaG) to activate a glucuronide prodrug (BHAMG) of p-hydroxyaniline mustard (pHAM) at hepatoma ascites in Sprague-Dawley rats. Injection i.p. of 500 microg RH1-betaG, a conjugate formed between recombinant betaG and monoclonal antibody RH1 with specificity for an antigen expressed on AS-30D rat hepatoma cells, into rats bearing AS-30D ascites resulted in the accumulation of 54 microg conjugate per 10(9) tumor cells after 2 hr. Ascites fluid and serum contained 0.53 and 0 microg/ml, respectively, RH1-betaG 2 hr after injection of the conjugate. Conjugate binding to AS-30D cells was heterogeneous and non-saturated, as determined by flow cytometry. BHAMG was less toxic than pHAM to SD rats based on measures of animal mortality, weight loss and hematological toxicity. Treatment of rats bearing established hepatoma ascites with 500 microg RH1-betaG followed 2 hr later with a single i.p. injection of 30 mg/kg BHAMG or 3 i.p. injections of 10 mg/kg BHAMG 2, 3 and 4 hr later resulted in the cure of 6/8 and 8/8 animals, respectively. Treatment with BHAMG or pHAM alone did not produce cures, whereas treatment with a control antibody-betaG conjugate and BHAMG produced significantly greater hematological toxicity compared to treatment with RH1-betaG and BHAMG. All cured rats were completely protected from rechallenge with 2 x 10(7) AS-30D cells, indicating that successful treatment of animals induced protective immunity. 相似文献
14.
Control of peak sidelobe level in adaptive arrays 总被引:1,自引:0,他引:1
Renbiao Wu Zheng Bao Yuanliang Ma 《Antennas and Propagation, IEEE Transactions on》1996,44(10):1341-1347
Adaptive beamforming techniques are now widely used to reject interference (jammer/clutter) signals in radar, communication, and sonar applications. In adaptive arrays using the sample matrix inversion (SMI) algorithm, inadequate estimation of the covariance matrix results in adaptive antenna patterns with high sidelobes and distorted mainbeams. In this paper, a method is proposed to precisely control the peak (rather than average) sidelobe level of adaptive array patterns. The proposed method is also generalized to adaptive array antennas with moderate bandwidth and large random amplitude and phase errors. Theoretical analysis and simulation results are provided to illustrate the performance of the method proposed 相似文献
15.
要提高曲线轮廓汉字的还原质量, 需要在字形还原时采用网格适配技术本文介绍了网格适配的基本原理, 并在分析汉字字形还原失真现象的基础上, 给出了我们自己设计并实现的适合于曲线轮廓汉字特点的二种网格适配方法, 即动态的补象素算法和曲线轮廓汉字的技术 相似文献
16.
Ju D.-C.R. Chuan-Lin Wu Carini P. 《Parallel and Distributed Systems, IEEE Transactions on》1994,5(10):1113-1120
We present a classification scheme for array language primitives that quantifies the variation in parallelism and data locality that results from the fusion of any two primitives. We also present an algorithm based on this scheme that efficiently determines when it is beneficial to fuse any two primitives. Experimental results show that five LINPACK routines report 50% performance improvement from the fusion of array operators 相似文献
17.
经济利润率是评价一个实际热力装置的主要指标之一。将有限时间热力学,非平衡量子统计理论和yong经济学相结合,导出了量子斯特林制冷机的最大利润率以及对应的性能界限,其结果与实际斯特林制冷机的优化设计和模型评估提供了一个最佳的预选方案。 相似文献
18.
目前,世界上最大的计算机网络Internet网,已成为通达150多个国家的国际互联网络。作为引导中国计算机用户进入Internet的中国公用计算机互联网CHINANET也正迅速发展。本文就Internet网的服务方式和入网方式进行了综述。 相似文献
19.
核电材料在模拟反应堆环境中应力腐蚀破裂测试技术与性能评价 总被引:1,自引:0,他引:1
杨武 《理化检验(物理分册)》1996,32(5):7-12
简要介绍了采用慢应变速率试验,U型弯曲和C形环试验等技术,分别对800合金,304和316及316Ti不锈钢A533B压力容器用多在模拟核反应堆环境中的应力腐蚀破裂敏感性性进行的试验研究的一些主要结果;并结合电化学测试和表面膜俄歇电子能谱分析结果进行了讨论。 相似文献
20.
CA/PAN中空纤维血浆分离膜的结构与性能 总被引:4,自引:2,他引:2
本研究以CA及PAN的共混溶液,通过干-湿法纺丝制取中空纤维,利用共混高聚物各组分在凝固剂中相分离速度的差异,形成具有稳定结构的中空纤维孔膜,该膜用于分离血液中的血浆成分具有良好效果。讨论了成型条件及添加剂等对膜结构、性能的影响,用SEM及图相分析仪、MAP压汞仪及DSC等分析手段,对膜的微孔结构、形态、孔尺寸及中空纤维膜的血浆通量和水通量等进行了系统的考查。 相似文献