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81.
以苏州七子山垃圾填埋场为背景,采用理论分析的方法,探讨山谷型垃圾填埋场合理的渗滤液收集系统的形式和定量计算方法。  相似文献   
82.
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems.  相似文献   
83.
Summary: Despite numerous deficiencies in some antihypertensive drug treatment trials, and some questionable selections of studies for inclusion in several meta-analyses, undoubtedly such trials have shown treatment benefits from reducing hypertension. Complications that can be corrected or prevented include malignant hypertension, hypertensive heart failure, stroke and coronary artery morbidity. the all-cause mortality has been lowered in several trials. the benefits have been seen in subjects aged over 60 years, in women and men, and in patients with isolated systolic hypertension. the benefits have been achieved using a wide range of drugs, not only with beta-blockers or diuretics. Non-pharmacological means of lowering blood pressure have not been evaluated in relation to morbidity.  相似文献   
84.
This paper studies global bifurcation structure of the chaotic neural networks applied to solve the traveling salesman problem (TSP). The bifurcation analysis clarifies the dynamical basis of the chaotic neuro-dynamics which itinerates a variety of network states associated with possible solutions of TSP and efficiently ‘searches’ for the optimum or near-optimum solutions. By following the detailed merging process of chaotic attractors via crises, we find that the crisis-induced intermittent switches among the ruins of the previous localized chaotic attractors underly the ‘chaotic search’ for TSP solutions. On the basis of the present study, efficiency of the ‘chaotic search’ to optimization problems is discussed and a guideline is provided for tuning the bifurcation parameter value which gives rise to efficient ‘chaotic search’.  相似文献   
85.
Summary The sensitivity of the cochlea is dependent upon maintenance of a delicate homeostatic environment. One mechanism which participates in providing this environment is the autoregulation of cochlear blood flow. This autoregulation is ensured through the interaction of sympathetic, peptidergic and hemodynamic mechanisms. The current study demonstrates an adaptation that also participates in cochlear blood flow autoregulation. Specifically, an anterior inferior cerebellar arterial network is described and the relative contributions of each of its vessels to total cochlear blood flow is measured using laser Doppler flowmetry. The results show that each collateral vessel contributes to the blood supply of the cochlea and that reperfusion is accompanied by hyperemia. These findings suggest an adaptation that provides stable blood flow through redundancy and compensatory potential. Additionally, these observations have implications for experimental models of ischemia.  相似文献   
86.
真皮下血管网皮瓣修复感染创面的研究   总被引:2,自引:0,他引:2  
目的:探讨真皮下血管网皮瓣的抗菌能力和临床修复感染创面的应用。方法:以家猪为实验动物,在臀部两侧分别形成传统的岛状皮瓣和真皮下血管网岛状皮瓣,用细菌计数、吖啶橙荧光染色测定白细胞吞噬指数和白细胞内杀菌率等方法,进行对比。结果:真皮下血管网岛状皮瓣的抗菌力明显降低。 1989年起临床应用 5例,创面彻底清创后用吻合血管的真皮下血管网游离皮瓣修复,全部成活。结论:该皮瓣抗菌力虽低于传统皮瓣,但仍可用于修复感染创面。  相似文献   
87.
Elevated body mass index and mortality risk in the elderly   总被引:2,自引:0,他引:2  
The purpose of this report was to perform a systematic review and meta-analysis of the studies examining the impact of an elevated body mass index (BMI) on mortality risk in elderly (> or =65 years) men and women. A variance-based method of meta-analysis was used to summarize the relationships from available studies. The summary relative risk of all-cause mortality from the 26 analyses that included a risk estimate for a BMI within the overweight range was 1.00 (95% confidence intervals, 0.97-1.03). The summary relative risk of all-cause mortality for the 28 analyses that included a risk estimate for a BMI within the obese range was 1.10 (1.06-1.13). These calculations indicate that a BMI in the overweight range is not associated with a significantly increased risk of mortality in the elderly, while a BMI in the moderately obese range is only associated with a modest increase in mortality risk.  相似文献   
88.
应用计算机网络系统提高门急诊管理水平   总被引:3,自引:0,他引:3  
作者介绍的门急诊计算机管理网络系统,应用软件使用FOXPRO2.5FORDOS语言,在两台网络服务器之间应用镜像技术,门诊号的录入使用光笔和条形码技术,实行划价、收费一体化,采用星型拓扑网络结构,保证了网络的先进性、安全性、稳定性和可扩充性。网络系统实现挂号、划价收费、调剂、药品使用管理、工作量统计及经济核算的全程闭环管理格局,有效地堵塞了管理和经济上的漏洞,提高了工作效率和管理水平。该系统已正常运行了12个月,并通过省级科技成果鉴定。  相似文献   
89.
Summary The efficacy and safety of ivermectin in the treatment of filariasis due to Wuchereria bancrofti was assessed by a meta-analysis of the results from 15 published clinical trials. Seven hundred and forty-eight microfilaraemic patients were enrolled in 7 dose-finding and 8 comparative studies. Administered as a single dose, ivermectin induced nearly complete clearance of microfilariae from the blood from the first day to 30 days post-treatment, followed by gradual recurrence of microfilaraemia and increase in its intensity. Higher doses of ivermectin showed greater clearance effects and maintained lower microfilaraemia levels for a longer time. The adverse reactions caused by the drug were flu-like, transient, generally mild and well tolerated by patients. The frequency and intensity of adverse reactions were strongly associated with pretreatment microfilaria counts in the blood, but independent of dose. The findings of the meta-analysis suggest that ivermectin given at a single annual dose of 200 μg/kg body weight or higher, whether or not in combination with DEC, has great potential for therapeutic strategies to control bancroftian filariasis.  相似文献   
90.
A. Grant 《Hernia》2002,6(3):130-136
Abstract Background. The EU Hernia Trialists Collaboration was established to provide reliable evaluation of newer methods of groin hernia repair. It involved 70 investigators in 20 countries. Materials and methods. Twenty eligible trials (5016 participants) of open mesh vs. non-mesh groin hernia repair were identified. Meta-analysis was performed using raw individual patient data where possible. Results. Fewer hernia recurrences were reported after mesh repair. There were no clear differences between mesh and non-mesh groups in complications. Overall, those in the mesh groups had a shorter hospital stay, quicker return to usual activities and less frequent persisting pain, but individual trial results varied. Conclusions. The review provides strong evidence that open mesh repair is associated with a reduction in the risk of recurrence of between 50% and 75%. There is also some evidence of quicker recovery and of lower rates of persisting pain following open mesh repair. Electronic Publication  相似文献   
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