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51.
Slow‐flow and no‐reflow phenomenon are taken to sudden loss of coronary artery flow, typically after stenting or angioplasty in primary PCI. Otherwise conventional therapy, we report a technique, which autologous blood into intracoronary to supply oxygen and break process thrombosis results in successfully management no‐reflow in primary PCI in ACS. 相似文献
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Shahid Ahmed MD PhD FRCPC Sukanya Pati MD Duc Le MD MSc FRCPC Kamal Haider MD Nayyar Iqbal MD FRCP 《Journal of surgical oncology》2020,122(2):144-154
Over the past two decades, gene expression profiling of breast cancer has emerged as an important tool in early-stage breast cancer management. The approach provides important information on underlying biological mechanisms, breast cancer classification, future risk potential of developing recurrent metastatic disease, and provides beneficial clues for adjuvant chemotherapy in hormone receptor (HR) positive breast cancer. Of the commercially available genomic tests for breast cancer, the prognostic and predictive value of 21-gene recurrence score tests have been validated using both retrospective data and prospective clinical trials. In this paper, we reviewed the current evidence on 21-gene expression profiles for HR-positive HER2-negative early-stage breast cancer management. We show that current evidence supports endocrine therapy alone as an appropriate adjuvant systemic therapy for approximately 70% of women with HR-positive, HER2-negative, node-negative breast cancer. Evolving evidence also suggests that 21-gene recurrence scores have predictive values for node-positive breast cancer and that chemotherapy can be avoided in more than half of women with nodes 1 to 3 positive HR-positive breast cancer. Furthermore, retrospective data also supports the predictive role of 21-gene recurrence scores for adjuvant radiation therapy. A prospective trial in this area is ongoing. 相似文献
54.
Quantitative functional lung imaging with synchrotron radiation using inhaled xenon as contrast agent. 总被引:6,自引:0,他引:6
S Bayat G Le Duc L Porra G Berruyer C Nemoz S Monfraix S Fiedler W Thomlinson P Suortti C G Standertskj?ld-Nordenstam A R Sovij?rvi 《Physics in medicine and biology》2001,46(12):3287-3299
Small airways play a key role in the distribution of ventilation and in the matching of ventilation to perfusion. The purpose of this study was to introduce an imaging method that allows measurement of regional lung ventilation and evaluation of the function of airways with a small diameter. The experiments were performed at the Medical Beamline of the European Synchrotron Radiation Facility. Monochromatic synchrotron radiation beams were used to obtain quantitative respiration-gated images of lungs and airways in two anaesthetized and mechanically ventilated rabbits using inhaled stable xenon (Xe) gas as a contrast agent. Two simultaneous images were acquired at two different energies, above and below the K-edge of Xe. Logarithmic subtraction of the two images yields absolute Xe concentrations. This technique is known as K-edge subtraction (KES) radiography. Two-dimensional planar and CT images were obtained showing spatial distribution of Xe concentrations within the airspaces, as well as the dynamics of filling with Xe. Bronchi down to 1 mm in diameter were visible both in the subtraction radiographs and in tomographic images. Absolute concentrations of Xe gas were calculated within the tube carrying the inhaled gas mixture, small and large bronchi, and lung tissue. Local time constants of ventilation with Xe were obtained by following the evolution of gas concentration in sequential computed tomography images. The results of this first animal study indicate that KES imaging of lungs with Xe gas as a contrast agent has great potential in studies of the distribution of ventilation within the lungs and of airway function, including airways with a small diameter. 相似文献
55.
Feasibility of synchrotron radiation computed tomography on rats bearing glioma after iodine or gadolinium injection 总被引:2,自引:0,他引:2
Le Duc G Corde S Elleaume H Estève F Charvet AM Brochard T Fiedler S Collomb A Le Bas JF 《European radiology》2000,10(9):1487-1492
The purpose of this work was to demonstrate the feasibility of a new imaging technique called synchrotron radiation computed
tomography (SRCT). This technique leads to a direct assessment of the in vivo concentration of an iodine- or gadolinium-labeled
compound. Rats bearing C6 glioma were imaged by MRI prior to the SRCT experiment. The SRCT experiments were performed after
a 1.3 g I/kg (n = 5) or a 0.4 g Gd/kg (n = 5) injection. Finally, brains were sampled for histology. The SRCT images exhibited contrast enhancement at the tumor location.
Ten minutes after injection, iodine and gadolinium tissular concentrations were equal to 0.80 ( ± 0.40) mg/cm3 and 0.50 ( ± 0.10) mg/cm3, respectively in the peripheral area of the tumor (respective background value: 0.20 ± 0.02 to 0.10 ± 0.01). Correlation
to MRI and histology revealed that the contrast uptake occurred in the most vascularized area of the tumor. The present study
summarizes the feasibility of in vivo SRCT to obtain quantitative information about iodine and gadolinium-labeled compounds.
Beyond brain tumor pathology, the SRCT appears as a complementary approach to MRI and CT, for studying iodine- and gadolinium-labeled
compounds by the direct achievement of the tissular concentration value in the tissue.
Received: 8 September 1999; Revised: 3 May 2000; Accepted: 4 May 2000 相似文献
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Langerhans cell histiocytosis (LCH) refers to a group of diseases of unknown etiology, typically discovered in childhood, characterized by the accumulation of Langerhans cells (white blood cells with large cell nuclei that may contain cytoplasmic histiocytosis X bodies) involving one or more organ systems, including bones, lungs, pituitary gland, skin, lymph nodes, and liver. This disease is also known as histiocytosis X or eosinophilic granuloma. Pulmonary LCH is common (identified in 40% of LCH patients) and may be isolated to the lung or involve other organs. Although LCH is characterized by clonal cell proliferation, adult LCH is considered likely to represent the manifestation of an aberrant immune response to an unspecified antigenic stimulus rather than a manifestation of tumor proliferation. We report a very complicated clinical case of LCH, with multiple organ damage that received a variety of different diagnoses. An LCH diagnosis was confirmed based on postoperative spinal cord pathology results and immunohistochemistry examinations. This case report highlights the clinical, laboratory, and imaging signs observed in this case that should be noted to help doctors more quickly recognize, diagnose, and treat similar cases. 相似文献
58.
0.5% Bupivacaine was administered around the sciatic nerve of rabbits by means of a catheter, over a period of ten days. Twenty nerves showed no histological changes, but in three there were areas of demyelination and axonal degeneration, especially near the surface of the nerve. However, similar changes occurred in two out of six nerves to which normal saline was administered instead, and it is suggested that the damage may have been caused by mechanical trauma from movement of the catheter. 相似文献
59.
Karen J. Dickinson Barbara L. Bass Duc T. Nguyen Edward A. Graviss Kevin Y. Pei 《Journal of the American College of Surgeons》2021,232(1):8-15.e1
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60.
T. Breteau T. Damay E. Duc J.-Y. Hascoët 《International Journal on Interactive Design and Manufacturing》2011,5(4):271-275
Marine propellers are complex surfaces that are usually machined with a perfect roughness not to disturb the theoretical flow.
Because this requirement is penalizing from a manufacturing point of view, the global objective of the study is to propose
an approach in which the machining parameters are linked to functional properties of the blade in order to cancel the polishing
phase. Indeed, the flow around the blade, associated with the performance of the propeller, is characterized with stream lines.
The approach that is presented in the paper links the tool trajectories to flow specifications, specifically by following
those stream lines. To benefit from a rotational axis on a five-axis-machine-tool, the idea is to compose a continuous trajectory,
especially at the leading edge, to mill the surface. As the tool paths follow specific hydrodynamical lines, the geometrical
information such as peak heights vary along the blade. Finally, the strategy allows multiaxial milling of a blade surface
in the context of design for manufacturing. 相似文献