一种可扩展的XPath查询最小化算法框架

XPath是XML的基本查询语言,XPath查询最小化对于提高XML数据库的查询性能具有重要意义.但是,由于XPath查询最小化是一个coNP完备问题,大部分已有的算法局限于处理简单的XPath片段.本文从一个新的角度入手,综合考虑完备性和高效性,提出了一个新的查询最小化框架,与已有算法"面向结点",即逐个删除冗余结点的解决思路不同,本文提出"面向树模式"的方式,即通过计算树模式的自同态映射,寻找目标结点集最小的自同态映射,进而求解最小等价查询树的方法.该方法具有较高的效率,而且在--Z..情况下是完备的,尤其是可以进一步扩展到更复杂的XPath片段.本文以此框架为基础,给出一个可以计算复杂查询模式的算法.     

Acute-phase response predicts erythropoietin resistance in hemodialysis and peritoneal dialysis patients

We defined erythropoietin (EPO) resistance by the ratio of the weekly EPO dose to hematocrit (Hct), yielding a continuously distributed variable (EPO/Hct). EPO resistance is usually attributed to iron or vitamin deficiency, hyperparathyroidism, aluminum toxicity, or inflammation. Activation of the acute-phase response, assessed by the level of the acute-phase C-reactive protein (CRP), correlates strongly with hypoalbuminemia and mortality in both hemodialysis (HD) and peritoneal dialysis (PD) patients. In this cross-sectional study of 92 HD and 36 PD patients, we examined the contribution of parathyroid hormone (PTH) levels, iron indices, aluminum levels, nutritional parameters (normalized protein catabolic rate [PCRn]), dialysis adequacy (Kt/V), and CRP to EPO/Hct. Albumin level serves as a measure of both nutrition and inflammation and was used as another independent variable. Serum albumin level (deltaR2 = 0.129; P < 0.001) and age (deltaR2 = 0.040; P = 0.040) were the best predictors of EPO/Hct in HD patients, and serum albumin (deltaR2 = 0.205; P = 0.002) and ferritin levels (deltaR2 = 0.132; P = 0.015) in PD patients. When albumin was excluded from the analysis, the best predictors of EPO/Hct were CRP (deltaR2 = 0.105; P = 0.003) and ferritin levels (deltaR2 = 0.051; P = 0.023) in HD patients and CRP level (deltaR2 = 0.141; P = 0.024) in PD patients. When both albumin and CRP were excluded from analysis in HD patients, low transferrin levels predicted high EPO/Hct (deltaR2 = 0.070; P = 0.011). EPO/Hct was independent of PTH and aluminum levels, PCRn, and Kt/V. High EPO/Hct occurred in the context of high ferritin and low transferrin levels, the pattern expected in the acute-phase response, not in iron deficiency. In well-dialyzed patients who were iron replete, the acute-phase response was the most important predictor of EPO resistance.     

EFFECTS OF IMPLEMENTATION OF 18 CLINICAL PATHWAYS ON COSTS AND QUALITY OF CARE AMONG PATIENTS UNDERGOING UROLOGICAL SURGERY

PURPOSE: We evaluated the effects on the costs and quality of care of implementation of 18 clinical pathways for urological operations. MATERIALS AND METHODS: From April 1997 to March 1998 patients undergoing 1 of 18 urological operations were treated according to clinical pathways. The outcomes in terms of length of hospital stay and admission charges of these patients were compared with those of patients treated between April 1996 and March 1997 before clinical pathways were implemented. We also selected 7 clinically relevant quality indicators to assess the quality of care before and after clinical pathway implementation. RESULTS: Of the 1,784 patients undergoing urological surgery from April 1997 to March 1998, 1,382 (77.5%) were treated according to 1 of the 18 clinical pathways. Before implementation 1,279 of 1,615 patients (79.2%) underwent these procedures. The length of hospital stay decreased from 5.5 to 4.9 days (p < 0.01) and the average hospital admission charges decreased by 12.9% (p < 0.01) after implementation. Five of the quality indicators, including the rate of surgical complications, were significantly improved after pathway implementation. The hospitalization rate was not affected (1.3 before versus 0.8% after implementation, p = 0.18). Variations from the clinical pathways occurred in 543 cases (39.3%) and affected the length of hospital stay only (11.6%) or the admission charge only (12.9%) more often than both (7.8%, p < 0.01) or neither (7.0%, p < 0.01). The most common variances in these patients were patient related (30.8%). CONCLUSIONS: Implementation of multiple clinical pathways in a urology department can improve urological practice by decreasing the length of hospital stay, admission charges and rate of surgical complications, and by improving the quality of care.     

Relationship between skin fold thickness and insulin resistance in the essential hypertensive patients in Vietnam

Background Previous studies reported a close relationship between obesity and insulin resistance in the essential hypertensive patients. Objective In this study, we examined the relationship between the skin fold thickness and insulin resistance then developed a formula to estimate the insulin resistance index according to the skin fold thickness in the essential hypertensive patients. Subjects and Methods Medical records of 80 patients (37 males, 43 females) were reviewed and the data were tabulated. Anthropometric indexes (including height, weight, waist circumference, hip circumference, and skins fold thickness at 5 fatty difference points on the Erdheim diagram), fasting plasma glucose and insulin concentration were recorded. The mean age was 57.0 ?9.2 years. The insulin resistance index was calculated following the Homeostasis Model Assessment (HOMA) formula. Results Compared with the group with BMI < 23 kg/m2, the group with BMI≥23 kg/m2 had higher fasting insulin concentration (8.85±4.97 pmol/L vs 15.60±8.70 pmol/L, P<0.001 ) and higher insulin resistance index in ( 2.15±1,24 vs 3.76±2.22, P<0.001). No significant difference in fasting plasma insulin concentration, insulin resistance index between male and female was observed (P > 0.05). There was a positive correlation between skin fold thickness and the fasting insulin concentration and insulin resistance index. The skin fold thickness at point A8 had the best coefficient correlated with fasting plasma insulin(r=0.79, P < 0.001) and insulin resistance index (r= 0.79, P < 0.001). A formula to estimate the insulin resistance index by skin fold thickness at point A8 as: Insulin resistance index = 0.12×[skin fold thickness at A8 point (mm)] - 1. Conclusion: In the essential hypertensive patients, the formula to estimate insulin resistance index as 0.12×[skin fold thickness at A8 point (mm)]-1 may predict accurately the level of insulin resistance. (J Geriatr Cardiol 2005; 2(4):228-232 )     

黄芪治疗放疗化疗后白细胞减少症的应用分析

目的:概述近年来有关黄芪治疗白细胞减少症的临床应用及其剂量范围,分析其临床变证应用特点和证型量效关系。方法:分别从黄芪治疗放疗化疗后白细胞减少症的临床有效率、黄芪的临床用量和黄芪参与治疗的主要证型3方面进行分析。结果:黄芪治疗放疗化疗后白细胞减少症的临床有效率多达90%以上,常用剂量为30g,所涉及的功效主要有气血双补、健脾补肾、益气健脾、补肾填精、益气养阴、消癥益气固本。结论:黄芪在治疗放疗化疗后白细胞减少症时发挥了补气升阳、补气摄血、补气行滞、祛瘀散结、益气固表、补气益阴、利水消肿、温里散寒等作用。     

野茼蒿的挥发性成分研究

目的：研究野茼蒿的挥发性成分。方法：用固相微萃取（solid-phase microextrations,SPME）和气相色谱-质谱（gas chromatography-mass spectrometry,GC-MS）联用仪对野茼蒿的挥发性成分进行测定。结果：从中共鉴定出37种化学成分。含量最多的3种成分是月桂烯（61.609%）、牛儿烯D（6.481%）、α-葎草烯（6.293%）。结论：茼蒿主要挥发性成分为烯烃。     

小牛血去蛋白提取物对胃溃疡患者的疗效评价

目的：探讨小牛血去蛋白提取物(DCBE)对胃溃疡的治疗作用。方法：选择年龄20～70岁之间，经胃镜检查确诊为活动期胃溃疡的住院患60例。治疗组32例采用静脉滴注DCBE(800mg，qd)和法莫替丁(100mg,bid)治疗；对照组28例采用静脉滴注法莫替丁(100mg，bid)单独治疗。用药2、4wk行胃镜检查，观察自觉缓解症状、时间、愈合率和总有效率。结果：治疗组自觉症状缓解时间明显缩短；给药后2、4wk治疗组及对照组胃镜检查溃疡愈合率分别为78.1％，46.4％及84.4％，71.4％。结论：DCBE能显促进胃溃疡的愈合。     

乙肝疫苗初免失败婴儿再免疫方法研究

目的探索乙肝疫苗初次全程免疫失败婴儿的再免疫方法.方法对乙肝疫苗全程免疫后乙肝病毒表面抗体(抗-HBs)和乙肝病毒表面抗原(HBsAg)均阴性的144名婴儿,随机分成5组,1组为对照组,其余4组分别采用不同的再免疫方法,观察再免成功率.结果抗-HBs总阳转率为93.79%,抗-HBs几何平均滴度(GMT)为546.97mIU/ml,各组抗-HBs阳转率分别为87.88%、90.91%、100%、96.88%;各组GMT分别为475.34mIU/ml、658.65mIU/ml、625.18mIU/ml、455.90mIU/ml.结论乙肝疫苗初免失败婴儿,再免成功率达93.79%.