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991.
Early diagnosis of glaucoma, which is the second leading cause of blindness in the world, can halt or slow the progression of the disease. We propose an automated method for analyzing the optic disc and measuring the cup-to-disc ratio (CDR) on stereo retinal fundus images to improve ophthalmologists' diagnostic efficiency and potentially reduce the variation on the CDR measurement. The method was developed using 80 retinal fundus image pairs, including 25 glaucomatous, and 55 nonglaucomatous eyes, obtained at our institution. A disc region was segmented using the active contour method with the brightness and edge information. The segmentation of a cup region was performed using a depth map of the optic disc, which was reconstructed on the basis of the stereo disparity. The CDRs were measured and compared with those determined using the manual segmentation results by an expert ophthalmologist. The method was applied to a new database which consisted of 98 stereo image pairs including 60 and 30 pairs with and without signs of glaucoma, respectively. Using the CDRs, an area under the receiver operating characteristic curve of 0.90 was obtained for classification of the glaucomatous and nonglaucomatous eyes. The result indicates potential usefulness of the automated determination of CDRs for the diagnosis of glaucoma.  相似文献   
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We report a case of T cell prolymphocytic leukemia (T-PLL) involving blast transformation. At the initial diagnosis, most peripheral blood cells demonstrated proliferation of indolent T cell small cell variants, i.e., small to medium prolymphocytes with inconspicuous nucleoli and a normal karyotype. These cells were positive for surface CD4, CD5, and CD7, and cytoplasmic CD3, but negative for surface CD3 and CD8 and cytoplasmic terminal deoxynucleotidyl transferase (TdT). The T cell receptor (TCR) Cβ1 gene was rearranged in the cells. Large prolymphocytes with prominent nucleoli, irregular nuclei, and cytoplasmic vacuoles that exhibited chromosome 8 trisomy were observed about 1.5 years later. The CD4+CD8− single positive effector memory T cells transformed into surface CD4+CD8+ double positive precursor T cells. The clonal TCR gene rearrangement patterns of these cells were identical throughout the clinical course, suggesting clonal blast transformation. The CD4+CD8+ cells demonstrated increased chromosome 8 trisomy combined with complex chromosome abnormalities with t(14;14)(q11.2;q32) containing a 14q32 chromosome after transformation. T cell leukemia 1a (TCL1a) (14q32.1) may be implicated in this case. The TCL1a oncoprotein is expressed in approximately 70% of T-PLL cases. The disease gradually developed resistance to chemotherapy, and the patient died of the disease. It is known that indolent T-PLL can become aggressive. Therefore, similar transformations may occur in other aggressive T-PLL cases, particularly those involving trisomy 8 and TCL1a.  相似文献   
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Intraoperative assessment of flow in the renal artery and vein after reconstruction is a crucial matter in kidney transplantation. Conventional Doppler ultrasound detects blood flow only in a limited area. The authors report a newly developed device that noninvasively visualizes the condition of perfusion of an entire allograft at one time from any angle and also clearly detects the state of anastomosis of the renal vessels. This near-infrared camera system provides the opportunity for the intraoperative assessment of the vasculature of renal allografts.  相似文献   
998.
A 73-year-old woman suffering from an abdominal aortic aneurysm (AAA), unstable angina, and low cardiac function (32% of ejection fraction) was scheduled for abdominal aortic replacement and coronary artery bypass grafting. However, before the scheduled operation the patient fell into cardiopulmonary arrest with ventricular fibrillation due to rupture of the AAA. Immediate cardiopulmonary resuscitation (CPR) using epinephrine and electrical defibrillation restored the spontaneous circulation. Following CPR, a continuous high-dose dopamine infusion (15 μg/kg/min) was initiated and emergent abdominal aortic replacement was performed. On arrival at the operating room, the patient showed serious hypotension, atrial fibrillation with multifocal ventricular premature contractions, and metabolic acidosis. Transesophageal echocardiography (TEE) suggested that the circulatory collapse might have resulted from diastolic dysfunction and deteriorated compliance of the left ventricular (LV) wall, possibly due to myocardial stunning induced by myocardial ischemia, and tachycardia induced by hypovolemia, both of which are influenced by high doses of catecholamine. We accordingly transfused adequate amounts of blood products and gradually decreased the infusion rate of dopamine to 4 μg/kg/min, while carefully monitoring blood pressure, central venous pressure, and TEE. By the end of surgery hemodynamic parameters had recovered to near normal levels. In post-resuscitated and hypovolemic patients, caution should be taken when administering high levels of exogenous catecholamines, which can induce myocardial stunning and circulatory collapse.  相似文献   
999.
A 21-year-old man with lymphadenopathy and Coombs-positive hemolytic anemia had been treated with steroid maintenance therapy. He developed nephrotic syndrome with size increase of lymphadenopathy. Lymph node examination disclosed angioimmunoblastic T-cell lymphoma (AITL). Light microscopy of a renal biopsy specimen showed typical features of membranous nephropathy (MN), such as bubbling appearance and spike formation. Immunofluorescence studies revealed no significant deposition of immunoglobulins. Electron microscopy showed sparse degenerative materials on the epithelial side of the glomerular basement membranes, with intervening spikes. These unique histological findings suggested secondary MN. High-dose steroid therapy followed by six courses of cyclophosphamide, doxorubicin, vincristine, and prednisolone (CHOP) therapy improved his symptoms. One-year follow-up revealed the patient in good health without any signs of relapse. Glomerular manifestations have rarely been reported in association with AITL. To our knowledge, this is the first reported case of nephrotic syndrome due to MN associated with AITL.  相似文献   
1000.
Primary hepatic leiomyosarcoma are rare tumors with less than 30 cases reported in the English literature.Non specific presentations and often diagnosis delayed until they reach a large size,is the norm with therapy leading to an often dismal prognosis.A 67-year-old man presented complaining of abdominal pain and a palpable abdominal mass since Jan 2010.Abdominal ultrasonography and abdominal computed tomography revealed a large tumor in the left lobe of the liver.Surgical exploration was undertaken and an extended left hepatectomy with extension onto the dorsal part of segment 8 preserving the MHV with partial resection of segment 6 was undertaken.The weight of the resected specimen was 1300 g of the left lobectomy specimen and 8 g of the segment 6 partial resection specimen.The pathology report confirmed the diagnosis of leiomyosarcoma.On immunohistochemistry,the tumor cells were positive for smooth muscle actin stain.The patient is on regular follow up and is currently 9 mo post resection with no evidence of recurrence.We report the case of a resected primary hepatic leiomyosarcoma and emphasize the need for a global database for these rare tumors to promote a better and broader understanding of this less understood subject.  相似文献   
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