小波变换结合矢量量化在图像编码中的应用

本文应用小波变换的ＭＡＬＬＡＴ算法，结合矢量量化和ＭＡＸ量化提出了一种新的图像压缩编码方法。实验结果表明给出了较高的压缩比和很好的图像还原效果。     

一种用于海量图像多分辨率局部重建的压缩算法

本文通过对Shaprio嵌入式小波系数零树编码方法的误差进行分析,针对海量图像数据量庞大的特点,提出了一种便于海量图像局部重建的量化算法。在该算法的基础上,结合位平面编码和游程编码,得到了比较高的压缩比。实验证明这种方法简单有效,易于编程实现,在对相关项目所涉及的海量图像进行处理过程中取得了较为满意的效果,是一种行之有效的压缩方法。     

基于小波域分块和码率分配的高分辨率图像低复杂度压缩方法

本文提出了一种适于高分辨率图像的低复杂度图像压缩方法,高分辨率图像小波变换后在小波域进行分块,然后采用EBCOT方法并行压缩,对各分块图像根据纹理复杂度分配码率,解决了采用传统图像域分块方法造成的图像不同区域由于复杂性差异较大而引起的简单部分恢复质量很好,而复杂度高的部分恢复质量差甚至不可用的问题,同时避免了图像域分块引起的“方块效应”。实验结果表明,本文算法重建效果十分接近全局压缩效果,尤其适合各区域复杂度差异很大的遥感图像 算法复杂度低,易于硬件实现,适于遥感图像的星载实时压缩。     

基于位平面编码的超光谱图像压缩方法

针对超光谱图像的特点和硬件实现的实际需要,提出了一种基于小波变换的前向预测帧间去相关超光谱图像压缩算法。通过图像匹配和帧间去相关,消除超光谱图像帧间的冗余,对残差图像的压缩采用基于小波变换的快速位平面结合自适应算术编码的压缩算法,按照率失真准则控制输出码流,实现了对超光谱图像的高保真压缩。通过实验证明了该方案的有效性, 基于小波变换的快速位平面结合自适应算术编码的压缩算法速度优于SPIHT,而且易于硬件实现。     

一种基于小波变换消除图像噪声方法

提出了一种基于小波变换消除图像噪声方法。该方法包括水平、垂直和对角线多个方向一维（1D）与二维（2D）两个小波变换消噪处理过程,汲取了1D方向数组小波变换消噪能较好保持方向性边沿的优点,消除了2D图像小波变换阈值法消噪造成的边沿模糊。与常规方法相比,此方法在有效抑制噪声的同时,能较大程度保留图像边沿。经实际噪声图像测试,具有误差小、信噪比高的特点。     

基于小波变换极大模的多模医学图像融合

多模态医学图像融合由于其对医学临床诊断的意义已引起广泛的关注,基于图像边缘特性的融合方法逐渐成为研究的重点。本文提出了一种基于离散二进小波变换的多尺度边缘检测和图像融合的方法,实现了特征级图像融合。不同于以往的从极大模值点直接重建图像,本文的算法利用极大模值点建立有效的融合规则,然后从融合的小波系数重构信号。融合图像的交互信息和峰值信噪比等检测指标表明此方法优于传统融合算法。     

基于方向对比度和局部方差的双树复小波图像融合算法

本文提出了一种在双树复小波（Dual-Tree ComplexW avelet Transform,DT-CWT）变换域下的融合策略,将小波域的方向对比度推广到复小波变换域,并将其与局部方差结合形成新的融合规则,实验结果表明该融合规则可以更好的突出融合图像的对比度信息,更有效的保留纹理和细节等局部特性。     

分形纹理分析及其在雷达目标识别中的应用

作为一种自然景物的模型,分形几何越来越多地受到了人们的关注。分形纹理分析是分形在图像处理中的应用研究的一个主要内容。注意到仅用分形维数特征不足以描述和区分不同的图像纹理,本文采用不同尺度下的方向性分维的变化曲线作为纹理图像的特征,对不同纹理的图像进行识别。实验表明这一方法是有效的。最后,本文讨论了该方法在雷达目标情况识别技术中的应用。     

改进的自适应阈值小波图像抑噪算法

深入分析VisuShrink阈值和NormalShrink阈值的原理,本文提出了一种改进的自适应阈值图像抑噪算法。该算法根据噪声在不同的小波分解尺度下呈现出不同的特性,估计每层的噪声方差,从而确定适合各个尺度级的自适应最优阈值,并依此对图像进行抑噪。实验结果表明,与传统的均值滤波、中值滤波、VisuShrink阈值法、自适应多阈值法、NormalShrink法、自适应阈值小波去噪法相比较,改进算法所得图像的视觉效果和峰值信噪比均得到改善。     

一种基于区域和Contourlet变换的多聚焦图像融合新方法

本文提出了一种基于区域和contourlet变换相结合的图像融合新方法。该方法首先对源图像进行contourlet变换，得到高频和低频图像；接着根据各尺度上高频图像的大小来调整源图像尺寸进行分割，得到多尺度分割图像；然后采用区域高频系数绝对值之和作为区域活动度来指导系数融合；最后进行contourlet逆变换得到融合图像。采用均方根误差、信噪比、边缘融合质量指标和加权融合质量指标4种准则来评价融合算法的性能。实验结果表明，本文方法不仅在客观评价指标上优于小波变换法，而且从主观评价上来看，本文的方法得到的融合图像更加的清晰。     

Intermittent docetaxel therapy with estramustine for hormone-refractory prostate cancer in Japanese patients

Background  We evaluated the efficacy and toxicity of intermittent docetaxel (DCT) with estramustine (EM) for hormone-refractory prostate cancer (HRPC). Methods  Fifteen patients were enrolled. They received injected DCT (70 mg/m² body surface) on day 1 in association with oral EM 560 mg/day (days 1–5). Treatments were repeated every 3 weeks. Serum prostate-specific antigen (PSA) levels were categorized based on the first three courses. Patients exhibiting either a response or stable disease (SD) could have a holiday from treatment (intermittent schedule). The holiday continued until elevation of the PSA level from the nadir baseline level occurred three times. All patients were evaluated for toxicity and quality of life (QOL). Survival curves were established using Kaplan-Meier graphs. Results  The median number of courses of DCT/EM therapy was five (range, 3–12 courses). The response rate of the first cycle was 53%: 3 patients with complete response (CR), 5 patients with partial response (PR), 4 patients with SD, and 3 patients with disease progression. Eight patients were able to begin the second re-entry cycle. No patients showed a CR, 2 patients exhibited PR, 4 patients had SD, and the overall response rate was 25%. The survival rates were 93% at 1 year, and 26.1% at 2 years Grade 3–4 anemia was observed in 2 patients (13.3%), neutropenia in 11 (73.3%), and thrombocytopenia in 2 (13.3%). The QOL scale showed good QOL after 6 months, with improvement in the score for nausea and vomiting. Conclusion  Intermittent DCT/EM therapy was well tolerated, and has the potential to prolong survival, with a high QOL, in patients with HRPC.     

Nutrient Restriction and Radiation Therapy for Cancer Treatment: When Less Is More

Calorie restriction (CR), or a diet modification aiming to reduce the total intake of calories by 20%–40%, has been shown to increase longevity across multiple species. Recently, there has been growing interest in investigating the potential role of CR as a treatment intervention for age-related diseases, such as cancer, because an increasing body of literature has demonstrated a metabolic component to both carcinogenesis and tumor progression. In fact, many of the molecular pathways that are altered with CR are also known to be altered in cancer. Therefore, manipulation of these pathways using CR can render cancer cells, and most notably breast cancer cells, more susceptible to standard cytotoxic treatment with radiation and chemotherapy. In this review article we demonstrate the laboratory and clinical evidence that exists for CR and show compelling evidence through the molecular pathways CR induces about how it may be used as a treatment in tandem with radiation therapy to improve our rates of disease control.     

Four‐dimensional computed tomography (4DCT): A review of the current status and applications

The applications of conventional computed tomography (CT) have been widely researched and implemented in clinical practice. A recent technological innovation in the field of CT is the emergence of four‐dimensional computed tomography (4DCT), where a three‐dimensional computed tomography volume containing a moving structure is imaged over a period of time, creating a dynamic volume data set. 4DCT has previously been mainly utilised in the setting of radiation therapy planning, but with the development of wide field of view CT, 4DCT has opened major avenues in the diagnostic arena. The aim of this study is to provide a comprehensive narrative review of the literature regarding the current clinical applications of 4DCT. The applications reviewed include both routine diagnostic usage as well as an appraisal of the current research literature. A systematic review of the studies related to 4DCT was conducted. The Medline database was searched using the MeSH subject heading ‘Four‐Dimensional Computed Tomography’. After excluding non‐human and non‐English papers, 2598 articles were found. Further exclusion criteria were applied, including date range (since wide field of view CT was introduced in 2007), and exclusion of technical/engineering/physics papers. Further filtration of papers included identification of Review papers. This process yielded 67 papers. Of these, exclusion of papers not specifically discussing 4DCT (cone beam, 4D models) yielded 38 papers. As part of the review, the technique for 4DCT is described, with perspectives as to how it has evolved and its benefits in different clinical indications.     

Clinical workflow optimization to improve 4DCT reconstruction for Toshiba Aquilion CT scanners

Respiratory motion remains a source of major uncertainties in radiotherapy. Respiratory correlated computed tomography (referred to as 4DCT) serves as one way of reducing breathing artifacts in 3D-CTs and allows the investigation of tumor motion over time. The quality of the 4DCT images depends on the data acquisition scheme, which in turn is dependent on the vendor. Specifically, the only way Toshiba Aquilion LB CT scanners can reconstruct 4DCTs is a cycle-based reconstruction using triggers provided by an external surrogate signal. The accuracy is strongly dependent on the method of trigger generation. Two consecutive triggers are used to define a breathing cycle which is divided into respiratory phases of equal duration. The goal of this study is to identify if there are advantages in the usage of local-amplitude based sorting (LAS) of the respiration motion states, in order to reduce image artifacts and improve 4DCT quality. Furthermore, this study addresses the generation and optimization of a clinical workflow using as surrogate motion monitoring system the Sentinel? (C-RAD AB, Sweden) optical surface scanner in combination with a Toshiba Aquilion LB CT scanner. For that purpose, a phantom study using 10 different breathing waveforms and a retrospective patient study using the 4DCT reconstructions of 10 different patients has been conducted. The error in tumor volume has been reduced from 2.9 ± 3.7% to 2.7 ± 2.6% using optimal cycle-based triggers (manipulated CBS) and to 2.7 ± 2.2% using LAS in the phantom study. Moreover, it was possible to decrease the tumor volume variability from 5.0 ± 3.6% using the original cycle-based triggers (original CBS) to 3.5 ± 2.5% using the optimal triggers and to 3.7 ± 2.7% using LAS in the patient data analysis. We therefore propose the usage of the manipulated CBS, also with regard to an accurate and safe clinical workflow.     

A case of advanced breast cancer effectively treated with tamoxifen]

A 69-year-old female with advanced breast cancer was daily administered 20 mg of tamoxifen. After 4 months, her left breast tumor decreased in size. Left breast tumor and metastatic lymph nodes disappeared completely (CR) 7 months later. CR has been continued for 6 months up to the present, and the patient has been enjoying favorable quality of life.     

Characteristics and clinical application of a treatment simulator with Ct-option

Background and purpose: The integration of a scanner for computed tomography (CT) and a treatment simulator (Sim-CT, Elekta Oncology Systems, Crawley, UK) has been studied in a clinical situation. Image quality, hounsfield units (HU) and linearity have been evaluated as well as the implications for treatment planning. The additional dose to the patient has also been highlighted.

Material and methods: Image data is acquired using an array of solid state X-ray detectors attached externally to the simulator's image intensifier. Three different fields of view (FOV: 25.0 cm, 35.0 cm and 50.0 cm) with 0.2 cm, 0.5 cm and 1.0 cm slice thickness can be selected and the system allows for an aperture diameter of 92.0 cm at standard isocentric height. The CT performance has been characterized with several criteria: spatial resolution, contrast sensitivity, geometric accuracy, reliability of hounsfield units and the radiation output level. The spatial resolution gauge of the nuclear associates quality phantom (NAQP) as well as modulation transfer functions (MTF) have been applied to evaluate the spatial resolution. Contrast sensitivity and HU measurements have been performed by means of the NAQP and a HU conversion phantom that allows inserts with different electron densities. The computed tomography dose index (CTDI) of the CT-option has been monitored with a pencil shaped ionization chamber. Treatment planning and dose calculations for heterogeneity correction based on the Sim-CT images generated from an anthropomorphic phantom as well as from ten patients have been compared with similar treatment plans based on identical, yet diagnostic CT (DCT) images.

Results: The last row of holes that are resolved in the spatial resolution gauge of the NAQP are either 0.150 cm or 0.175 cm depending on the FOV and the applied reconstruction filter. These are consistent with the MTF curves showing cut-off frequencies ranging from 5.3 lp/cm to 7.1 lp/cm. Linear regression analysis of HU versus electron densities revealed a correlation coefficient of 0.99. Contrast, pixel size and geometric accuracy are within specifications. Computed tomography dose index values of 0.204 Gy/As and 0.069 Gy/As have been observed with dose measurements in the center of a 16 cm diameter and 32 cm diameter phantom, respectively for large FOV. Small FOV yields CTDI values of 0.925 Gy/As and 0.358 Gy/As which is a factor ten higher than the results obtained from a DCT under similar acquisition conditions. The phantom studies showed excellent agreement between dose distributions generated with the Sim-CT and DCT HU. The deviations between the calculated settings of monitor units as well as the maximum dose in three dimensions were less than 1% for the treatment plans based on either of these HU both for pelvic as well as thoracic simulations. The patient studies confirmed these results.

Conclusions: The CT-option can be considered as an added value to the simulation process and the images acquired on the Sim-CT system are adequate for dose calculation with tissue heterogeneity correction. The good image quality, however, is compromised by the relative high dose values to the patient. The considerable load to the conventional X-ray tube currently limits the Sim-CT to seven image acquisitions per patient and therefore the system is limited in its capability to perform full three-dimensional reconstruction.     

复方苦参注射液治疗癌症疼痛患者90例疗效观察

目的探讨复方苦参注射液对晚期癌症疼痛的临床疗效。方法选取新入院的90例晚期癌症并疼痛患者,使用复方苦参注射液20ml加入250ml0．9氯化钠溶液或5％葡萄糖静脉滴注,40～60滴／min,每日1次,连用28d。观察轻、中、重度癌痛患者止痛效果、患者生活质量改善情况、不同中医证型患者疼痛改善情况及不良反应。结果不同癌痛分级患者疗效：轻度疼痛完全缓解（CR）率28．57％（10／35）,部分缓解（PR）率54．29％（19／35）,轻度缓解（MR）率5．71％（2／35）,总有效率88．57％（31／35）;中度疼痛CR率10．00％（3／30）,PR率23．33％（7／30）,MR率36．67％（11／30j,总有效率70．00％（21／30）;重度疼痛PR率4．00％（1／25）,MR率12．00％（2／25）,总有效率16．00％（4／25）。90例癌痛患者生存质量改善：治疗前（21．04±4．92）分,治疗后（33．52±5．98）分,二者差异有统计学意义（t=14．07,P=0．00）。中医分型：90例癌痛患者中,痰瘀互结型最多,为26例（28．99％）,脾肾阳虚最少,为10例（11．11％）;不同中医证型的癌痛缓解程度：痰瘀互结型总有效率最高,为88．46％（23／26）,脾肾阳虚型总有效率最低,为20．00％（2／10）。全组病例只有1例出现皮疹,未发现消化道、骨髓、心、肝、肾等组织器官的不良反应。结论复方苦参注射液对轻、中度癌痛具有较好的止痛作用,并可改善患者生存质量,对痰瘀互结型疗效显著,为安全有效的中药制剂。     

Late Relapse in Hodgkin's Disease: Report of Five Cases and a Review of the Literature

During the past 15 years the treatment of Hodgkin's disease (HD) with chemo/radiotherapy has been shown to appreciably improve the long-term prognosis of patients, even those with more advanced disease. In the past it was accepted that the probability of primary relapse 5 years after achieving complete remission (CR) was small and a 5-year disease-free period was sufficient to be considered as a cure. During the past 15 years, however, more data has been published relating to late relapses in these patients after an initial “cure” has been achieved. This report briefly examines our own experience with five patients initially “cured” who relapsed 5 to 11 years after achieving CR and also reviews recent literature on the subject. The phenomenon of late relapse has thus become a more important issue in the management of patients with HD.     

平消胶囊与抗癌药物联用治疗晚期肺癌40例报告

本文采用抗癌中成药平消胶囊与抗癌药物司漠司汀（Me－CCNU），5-氟脲嘧啶多相脂质体（139－3）联用，治疗晚期肺癌40树．疗效CR＋PR30％（12／40），优于对照组20％（4／20）．与国内外文献报道相比疗效相似．本文结果表明，平消胶囊改善临床症状，延长生存期。副反应轻（包括骨髓抑制），经两组对照，（P＜0．05或＜0．01）．对肺癌疗效更佳，服药后，食欲增加，精神好转，疼痛减轻，能提高患者的生活质量．     

Serum M-spike and transplant outcome in patients with multiple myeloma

High dose therapy with autologous stem cell transplantation (HDT-ASCT) has prolonged survival in patients with multiple myeloma. Patients who achieve a complete response (CR) benefit the most from this form of therapy. Thus, achieving a CR is an important goal of therapy and it will be beneficial if the probability of achieving CR can be determined for any patient before transplant. Here we report that pretransplant monoclonal protein level (M-spike) was found to be an important predictor. Thus, we used knowledge of the rate of M-protein production by myeloma cells together with the clearance of the protein to estimate the pretransplant disease burden. We show that the pretransplant disease burden, based on the M-spike, is the only predictor for achieving CR. A simple function that describes this probability is presented. We also provide an estimate of the rate of tumor regrowth in patients who obtain a CR and in patients who only get a partial response with HDT-ASCT. The significant expansion of myeloma cells after HDT-ASCT is clearly evident. Clinical trials must be designed that take into account these kinetic aspects of the disease.