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81.
Background and Objective. The Thrombus Aspiration during Percutaneous coronary intervention in Acute myocardial infarction Study (TAPAS) has shown that thrombus aspiration improves myocardial perfusion and clinical outcome compared with conventional primary percutaneous coronary intervention (PCI) in patients with ST-segment-elevation myocardial infarction. Impaired myocardial perfusion due to spontaneous or angioplasty-induced embolisation of atherothrombotic material also occurs in patients with non-ST-elevation myocardial infarction (NSTEMI). The aim of this study is to determine whether thrombus aspiration before stent implantation will result in improved myocardial perfusion in patients with NSTEMI compared with conventional PCI. Study design. The study is a single-centre, prospective, randomised trial with blinded evaluation of endpoints. The planned inclusion is 540 patients with acute NSTEMI who are candidates for urgent PCI. Patients are randomised to treatment with manual thrombus aspiration or to conventional PCI. The primary endpoint is the incidence of myocardial blush grade 3 after PCI. Secondary endpoints are coronary angiographic, histopathological, enzymatic, electrocardiographic and clinical outcomes including major adverse events at 30 days and one year. Implications. If thrombus aspiration leads to significant improvement of myocardial perfusion in patients with acute NSTEMI it may become part of the standard interventional approach. (Neth Heart J 2009;17:409–13.)  相似文献   
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超声成像无创、无放射性、低成本、实时成像的优点,使其成为目前世界上应用最广的成像手段之一。特别是超声造影剂引入之后,超声成像的图像分辨率和灵敏度得到了大大提高,使超声成像在临床上得到了进一步应用。近年来,随着分子生物学和超声成像技术的不断发展,人们提出了"超声分子成像"的概念。它是一项结合了分子靶向造影剂和超声影像技术的能在分子水平下观察病理变化的新兴技术,目前这一技术还处于研究初期阶段。但大量临床前的研究成果已表明超声分子成像在诊断血管生成、炎症和血栓三种疾病具有很大应用前景。本文主要综述了目前常用超声造影剂的种类以及超声分子成像技术的研究现状,并对该技术进行了讨论和展望。  相似文献   
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Introduction

Thrombus ages, defined as four relative age phases, are related to different compositions of the intraluminal thrombus (ILT) in the abdominal aortic aneurysm (AAA) (Tong et al., 2011b). Experimental studies indicate a correlation between the relative thrombus age and the strength of the thrombus-covered wall.

Methods

On 32 AAA samples we performed peeling tests with the aim to dissect the material (i) through the ILT thickness, (ii) within the individual ILT layers and (iii) within the aneurysm wall underneath the thrombus by using two extension rates (1 mm/min, 1 mm/s). Histological investigations and mass fraction analysis were performed to characterize the dissected morphology, to determine the relative thrombus age, and to quantify dry weight percentages of elastin and collagen in the AAA wall.

Results

A remarkably lower dissection energy was needed to dissect within the individual ILT layers and through the thicknesses of old thrombi. With increasing ILT age the dissection energy of the underlying intima–media composite continuously decreased and the anisotropic dissection properties for that composite vanished. The quantified dissection properties were rate dependent for both tissue types (ILT and wall). Histology showed that single fibrin fibers or smaller protein clots within the ILT generate smooth dissected surfaces during the peeling. There was a notable decrease in mass fraction of elastin within the thrombus-covered intima–media composite with ILT age, whereas no significant change was found for that of collagen.

Conclusions

These findings suggest that intraluminal thrombus aging leads to a higher propensity of dissection for the ILT and the intima–media composite of the aneurysmal wall.  相似文献   
86.
Fine needle aspiration cytodiagnosis of secretory carcinoma of the breast   总被引:2,自引:0,他引:2  
Secretory carcinoma (SC) of the breast is a rare variant of breast malignancy and its cytological features in fine needle aspirates have only recently been described. In this communication, our experience with four cases of SC of the breast is presented in which the diagnosis was established on fine needle aspiration cytology (FNAC). In all cases, the samples were cellular and featured diffuse, prominent, intracytoplasmic vacuoles and secretion in malignant cells and occasional signet-ring like forms. The cytodiagnosis of SC in all the cases correlated with subsequent examination of cell blocks of the aspirate and tissue. Cytochemical stains showed diffuse positivity for mucin by alcian blue stain in the vacuolated cells which was periodic acid-Schiff positive and resistant to diastase digestion. Oil-red O staining was negative. Immunopositivity to carcinoembryonic antigen, cytokeratin (CAM 5.2), B72.3 and epithelial membrane antigen was found in malignant cells. The cytodiagnostic criteria for SC of the breast, characteristic cytological features which are useful in a correct FNAC diagnosis and differentiation from other pertinent breast carcinomas, are discussed.  相似文献   
87.
Scrape cell-block technique for fine needle aspiration cytology smears   总被引:1,自引:0,他引:1  
An inconclusive diagnosis on fine needle aspiration cytology (FNAC) may be due to poor spreading and presence of thick tissue fragments despite aspiration of adequate material. Repeat aspiration may not be possible especially when aspirates of deep seated organs have been obtained by image guided techniques. We have resorted to a 'scrape cell-block' (SCB) technique in such cases. In this technique the cellular material on the slides which had already been fixed and stained, was carefully removed by scraping following destaining and then processed as a cell block. SCB interpretation was then compared with the smear diagnosis and histological diagnosis, wherever available. A total of 27 cases were studied. In 12 cases SCB slides added information to the FNAC smears. In 14 cases SCB did not offer any additional information. SCB was inconclusive in one case. Final histological correlation was available in eight cases and the SCB diagnosis was confirmed in six cases, whereas in two cases SCB failed to identify the tumour. Immunocytochemistry (ICC) was done in one case. SCB is a useful technique to make the best use of the available material when reaspiration is difficult.  相似文献   
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This study is a review of the quality of FNA cytology results for breast lesions approximately 18 months before and 10 months after a change from a rapid diagnosis FNA service with consultant pathologist aspirators to a conventional FNA service with clinician aspirators of varied experience. The setting was symptomatic breast clinic in a large hospital in rural New Zealand acting as a tertiary referral centre for a population of 550,000. The results were collected retrospectively and prospectively. The quality of results for pathologist aspirators (total 810) and clinician aspirators (total 403) was compared using the definitions of the NHS Breast Screening Program Guidelines for Cytology Procedures and Reporting in Breast Cancer Screening. There were statistically significant differences in specificity (biopsy cases only) with 73% for pathologists and 49% for clinicians, specificity (full) with 74% and 56%, inadequate rate with 23% and 37%, and complete sensitivity with 76% and 67%. The use of pathologist aspirators allowed the specimens to be reported in a few minutes. Specimens taken by clinicians took at least 30 min to report. The financial aspects of the two approaches are discussed. When compared with clinician aspirators, pathologist aspirators obtained better quality results and these were reported more quickly.  相似文献   
89.
Collagenous spherulosis is a rare incidental finding seen in association with benign breast lesions. Cytological findings in three cases of collagenous spherulosis diagnosed on fine needle aspiration are presented. The presence of hyaline pink globules surrounded by benign myoepithelial cells in Giemsa stained smears was a diagnostic feature. Associated lesions were atypical papillary hyperplasia (2) and fibroadenoma (1). Adenoid cystic carcinoma was the close differential diagnosis on cytology. Awareness of this entity is important to avoid a false positive diagnosis of malignancy.  相似文献   
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