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1.
AIMS: The degradation of the extracellular matrix is intrinsic to the invasion and progression of cancer. Matrix metalloproteinase (MMP)-2 and -9 and their natural inhibitors are involved in this process. The study aims to investigate if plasma MMP-2, -9 and tissue inhibitor of metalloproteinase-1 (TIMP-1) can be useful markers in the diagnosis and prognosis of colorectal cancer (CRC) metastatic liver disease. METHODS: Fifty-seven patients undergoing liver metastasis operation were followed prospectively. ProMMP-2, -9 and TIMP-1 plasma levels were determined by zymography and ELISA, before and after the resection of liver metastases. Data were compared with those of healthy controls (n=51) and primary CRC patients (n=94). The diagnostic and prognostic potential was investigated with ROC-curves and Kaplan-Meier survival analysis. RESULTS: Plasma proMMP-2 levels were lower (P<0.001), and TIMP-1 levels higher (P<0.001) in CRC metastatic liver disease than in healthy controls. If compared to those in primary CRC patients, no differences were found. In ROC-curves, the area under the curve was 0.48 and 0.61 for proMMP-2 and -9, respectively. Plasma proMMP-2, -9 and TIMP-1 levels were unsuitable to predict survival. In both diagnostic and prognostic examinations, CEA proved to be a better marker. In the postoperative follow-up, protracted low levels of proMMP-2 seemed related to disease recurrence. CONCLUSION: The preoperative plasma proMMP-2, -9 and TIMP-1 levels have no potential value as diagnostic or prognostic markers in CRC liver metastatic disease.  相似文献   
2.
个体化下肢小腿假肢接受腔设计的生物力学评价技术研究   总被引:3,自引:0,他引:3  
作为传递体重、固定假肢的部件 ,接受腔对于小腿假肢使用的舒适性和方便程度有决定性的作用。本研究建立了基于有限元应力分析的小腿假肢生物力学评价技术平台 ,实现了小腿残端 /接受腔 3D几何建模与信息交互、三维有限元自动建模及应力分析。 3D模型与信息交互的实现基于得到广泛支持的OpenGL技术 ,有限元模型的构建采用了专门针对小腿残端 /接受腔结构特点的自动建模方法 ,通过构建档案数据库系统作为整个系统的操作平台。该技术平台可与现有的CAD/CAM系统相结合 ,为接受腔的个体化设计提供生物力学定量化依据。其临床应用将改善传统的设计流程 ,提高设计效率。同时 ,它也是未来构建接受腔设计专家 /智能系统的基础。  相似文献   
3.
Aim of this research was to test the hypothesis that marginal gap measurements by a digital microscopic image processing computer are reproducible. Light microscopic images of the margins of Artglass partial crowns on stone dies were obtained with a 3CCD color video camera, digitized and processed. Ten measuring points were painted on a 0.5 mm section of the finish line of the preparation. The opposite corresponding measuring points on the margin of the partial crown were painted as well. The distance (marginal gap) between two corresponding points was painted and calculated by the computer. Reproducibility (precision) is reflected in the ability to reproduce the same measurement results in repeated measurements (n = 5). The reproducibility error was expressed as the coefficient of variation (CV) in percent (%). The localization of the corresponding measurement points and the calculation of the marginal gap were performed without errors. For a marginal gap between 15-50 microns the average measurement error was 3% or 0.45-1.5 microns. It was concluded that the measurement of the gap between two points by the digital image processing computer was reproducible. The measurement error was neglectable given that a clinically acceptable marginal gap is 100 microns.  相似文献   
4.
碱离子水饮用后血小板聚集率的的变化(附30例报告)   总被引:1,自引:0,他引:1  
目的:报告30例饮用豪斯牌碱离子水前、后血小板聚集率的变化。方法:饮用碱离子水前、后(2~3月,>3~6月)作比浊法血小板聚集试验,以1分钟、5分钟及5分钟内最大聚集率(Max%)为指标,同时检测部分血粘度指标及凝血因子,并用自动生化仪检测血糖、血脂、主要电解质及部分肝、肾功能。结果:饮碱离子水后,血小板聚集率明显下降,而以疾病组(Max>80%)下降尤为明显,P均<0.001。饮碱离子水后血小板聚集率的下降,部分可能与损伤的血管内皮得到修复有关。主要电解质及部分肝、肾功能无明显异常改变。结论:由于心、脑血管血栓性疾病患者血小板聚集率多明显升高,饮碱离子水后血小板聚集率明显下降,且长期饮用对主要电解质及部分肝、肾功能无明显异常改变,作者认为碱离子水使用方例、安全、有效、价廉,因而对心、脑血管血栓性疾病防治方面可能是一种积极的辅助方法,值得临床进一步探索。  相似文献   
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7.
In a randomized controlled clinical trial 74 patients who required immediate dentures were randomly treated with immediate overdentures on 2 lower canines or immediate complete dentures. Mandibular bone reduction was measured using oblique lateral cephalometric radiographs made at base-line and the results compared with those of one year and two years after denture treatment. Analysis of the data showed that the average bone reduction in the lower canine regions in the first year was 0.75 in the immediate overdenture group and 1.90 mm in the immediate complete denture group. In the posterior parts of the mandible the bone reduction was respectively 0.77 and 1.77 mm. The differences were statistically significant in all measured regions. The differences in the first two years were significant in all regions except the molar region. Retention of roots of canines beneath a mandibular denture in immediate denture patients, even when they were in poor condition, reduced the collapse of the alveolar processes in all region of the mandible.  相似文献   
8.
After cancer treatment in the head and neck area, mastication and speech are often affected. Some of the problems encountered can be solved by adequate dental rehabilitation. However, dental rehabilitation is often compromised for various reasons. The change in anatomy due to surgery often results in lack of denture-bearing mucosa. The effects of radiotherapy on the salivary glands and the mucosa result in dry oral tissue and diminished retention of removable dentures. Osseointegrated oral implants can help to solve these problems. Although implant treatment for patients with cancer of the head and neck is covered by the Dutch national health insurance, and there is therefore no financial obstacle, implants have not, so far, been widely used with these patients. In order to establish the possible reasons for this, an analysis was performed. Retrospective data on 95 consecutive patients were collected from records. The indication for the use of oral osseointegrated implants was reviewed. Analysis of the data showed that 45% did not need specific prosthetic rehabilitation. An indication for the use of osseointegrated implants was found in 25% of the patients. For various reasons, only 3% actually received implants. In striving to completely rehabilitate a cancer patient, the possible use of osseointegrated oral implants should be evaluated before the initial oncological treatment begins. The insertion of implants during the initial surgical procedure should be considered more often, with a view to reducing the number of surgical procedures.  相似文献   
9.
Objective : Acute abdominal pain is a common problem in childhood, and appendicitis is frequently diagnosed by general practitioners and doctors working in emergency departments. The objective of the present report was to determine the frequency of appendicitis in a group of children with acute abdominal pain presenting to the emergency department of a general hospital, as well as attempting to analyse the manner in which these patients were managed.
Methodology : The initial assessment in hospital (by resident hospital staff) of the study group of patients was analysed and their subsequent clinical progress documented.
Results : The present report shows that the vast majority of children with acute abdominal pain do not have appendicitis and that appendicitis is significantly over-diagnosed by junior hospital doctors.
Conclusions : Appendicitis is a clinical diagnosis, best made by an experienced member of the paediatric surgical team. Frequent review, with a minimum of investigations, provides the best means of making a rational decision regarding surgery.  相似文献   
10.
PURPOSE: To determine the biological modulatory dose of SU5416, we employed a novel trial design, where "dose de-escalation" was based on demonstrable biological changes observed at the maximum tolerated dose. If such an effect was shown, dose de-escalation to a predefined dose level would occur to determine if the lower dose exhibited the same amount of pharmacodynamic effect as the higher dose. EXPERIMENTAL DESIGN: Ten patients with advanced solid tumors were enrolled at each dose level. One of the following pharmacodynamic effects was considered significant: (a) a 35% decrease in microvessel density in sequential tumor biopsies and (b) a 35% decrease in blood flow within tumor as assessed by dynamic contrast-enhanced magnetic resonance imaging. In addition, soluble E-selectin, soluble intercellular adhesion molecule, soluble vascular cell adhesion molecule, and plasma vascular endothelial growth factor were measured sequentially. RESULTS: Nineteen patients were enrolled. Sequential tumor biopsies in all evaluable patients showed an increase in microvessel density. Only one patient met the intended pharmacodynamic end point of >35% reduction in blood flow. There was a significant increase in both soluble E-selectin and soluble intercellular adhesion molecule levels pretreatment versus levels at the time of removal of patients from study (P = 0.04 and P = 0.0007, respectively). Levels of serum fibrinogen rose with therapy. There was a trend toward increase in plasma vascular endothelial growth factor levels. CONCLUSION: SU5416 does not result in decreased blood flow in tumors or a decrease in microvessel density. This corresponds to the lack of clinical activity seen with this agent. Our clinical trial design termed dose de-escalation is a novel approach to determine the in vivo biological effects of targeted therapies in cancer patients.  相似文献   
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