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101.
102.
目的 介绍医科达数字化医用电子直线加速器控制软件里子项目和项目成分值(IPV)的工作原理,并具体说明控制软件通过三类子项目及其项目分项实时监测、控制子系统的运行状态。方法 首先介绍医科达数字化医用电子直线加速器的控制系统组成,然后介绍控制软件里子项目和项目分项的定义和分类,以及各类子项目的基本原理,最后通过分析高功率移相器的运动控制具体说明控制软件的子项目在实时监测、控制子系统运行状态的应用。结果 通过分析原理和举例详细、具体说明了控制软件IPV的工作原理及其应用,使用户尤其是维修人员能掌握相应理论知识,在日常使用和维修时能通过软件快速准确地查找运行参数,并根据相关子系统的控制原理分析问题和解决故障。结论 用户尤其是维修人员掌握这些子项目及其项目分项的工作原理,就能在日常使用或维修、校准时,快速准确地通过控制软件查看、校准运行参数,解决设备故障,并避免错误操作引起事故。  相似文献   
103.
嗜肺军团菌是一种可以引起军团菌肺炎和庞蒂亚克热的兼性胞内病原菌,主要侵染阿米巴原虫和人类巨噬细胞。该菌在宿主胞内能依靠Dot/Icm IVB型分泌系统产生的效应蛋白成功逃避溶酶体的降解。本文主要对嗜肺军团菌的致病物质、胞内存活与增殖机制及其效应蛋白的生物学功能进行综述,详细介绍嗜肺军团菌的毒力因子与致病机制,为军团病防治的研究提供新思路,也为其他胞内病原菌所致感染性疾病的研究提供重要的借鉴意义。  相似文献   
104.
Mycosis fungoides (MF) and Sézary syndrome (SS) are the most common types of cutaneous lymphoma, accounting for approximately 60% of cutaneous T-cell lymphomas. Diagnosis requires correlation of clinical, histologic, and molecular features. A multitude of factors have been linked to the aetiopathogenesis, however, none have been definitively proven. Erythrodermic MF (E-MF) and SS share overlapping clinical features, such as erythroderma, but are differentiated on the degree of malignant blood involvement. While related, they are considered to be two distinct entities originating from different memory T cell subsets. Differential expression of PD-1 and KIR3DL2 may represent a tool for distinguishing MF and SS, as well as a means of monitoring treatment response. Treatment of E-MF/SS is guided by disease burden, patients’ ages and comorbidities, and effect on quality of life. Current treatment options include biologic, targeted, immunologic, and investigational therapies that can provide long term response with minimal side effects. Currently, allogeneic stem cell transplantation is the only potential curative treatment.  相似文献   
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Primary amoebic meningoencephalitis is rare but fatal disease encountered in immunocompetent individuals. Here, we present a case of a previously healthy 8-month-old female child, who presented with features of meningoencephalitis of 2 days’ duration. Rapidly moving trophozoites of amoeba were observed in cerebrospinal fluid, which were confirmed to be Naegleria fowleri on polymerase chain reaction. Broad-spectrum antimicrobial therapy with ceftriaxone, vancomycin, amphotericin B and acyclovir was initiated. However, the patient deteriorated and left the hospital against medical advice. The isolation of N. fowleri in this case demands for increased awareness for prompt diagnosis and management in view of its high mortality.  相似文献   
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109.
This paper investigates the quantized sliding mode control of Markov jump systems with time‐varying delay. A dynamical adjustment law is explored to quantize the system output. By constructing an observer‐based integral sliding surface, a sliding mode controller is designed to take over the dynamical motion of state estimation and ensure the reachability of sliding surface. A new scaling manner is developed to build the bound between the system output and quantized error. With the help of separation strategies for controller synthesis and general transition probabilities and a lower bound theorem for nonlinear integral terms, a new synthesis method to ensure the required stability and meet the required performance is proposed in the form of linear matrix inequalities. The validity of the proposed control method is illustrated by a numerical example.  相似文献   
110.

Purpose

To assess the frequency and potential predictors of prostatic central gland tissue detachment (CGD), an enucleation-like reaction that sporadically occurred in a randomized controlled trial assessing efficacy and safety of prostatic artery embolization (PAE).

Materials and Methods

Trial data were analyzed to identify patients with CGD after PAE. Clinical parameters, MR imaging findings, technical details of PAE, and periinterventional data were compared between patients with and without CGD to identify parameters for prediction, induction, or early detection of CGD after PAE.

Results

CGD occurred after PAE in 3 of 48 patients (6.3%); these cases had good functional outcomes, but CGD was associated with increased risk of ejaculatory dysfunction and occurrence of complications. Frequency of preoperative transurethral bladder catheterization (100% vs 13.3%; P = .005), central gland index (mean ± standard deviation, 0.86 ± 0.02 vs 0.69 ± 0.14; P < .001), amount of particles applied (1.93 mL ± 0.12 vs 0.96 mL ± 0.36; P < .001), maximum early postoperative pain score (7.33 ± 2.08 vs 1.89 ± 2.40; P = .009), and blood C-reactive protein (CRP) levels after 48 hours (69.0 vs 18.58 mg/dL; P = .045) and 1 week (113.50 vs 5.16 mg/dL; P = .004) were significantly higher in cases of CGD.

Conclusions

CGD is a rare reaction that might be triggered by prostatic zonal anatomy, embolization technique, and mechanical or inflammatory processes. It should be considered in patients with severe postoperative pain and high CRP levels who experience voiding dysfunction after PAE to avoid complications. Investigation of larger cohorts might further elucidate this tissue response.  相似文献   
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