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In this article, myocardial perfusion in patients with a totally occluded left anterior descending artery reinjected by a normal right coronary artery is assessed using stress single photon emission computed tomography (SPECT). In all, 20 patients, with a totally occluded left anterior descending artery reinjected by normal right coronary artery, underwent myocardial single photon emission computed tomography imaging within 60 days of angiography. All patients had abnormal perfusion single photon emission computed tomography results and 70% had reversible defects. Perfusion defects at rest were present in 75% of patients, with perinecrotic residual ischemia in 45% of patients whereas for 30% of patients, no viable myocardium was detected in the collateral-dependent segments. In all, 25% of patients had no resting perfusion defects but all are presented with stress-induced ischemia. Collaterals are not protective against stress-induced ischemia, but they can preserve myocardial viability. This conclusion is highly supported by the presence of residual ischemia in the collateral-dependent segments. 相似文献
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Ilona Illes Sharron L. Pfueller Sonay Hussein Colin N. Chesterman John F. Martin 《British journal of haematology》1987,67(2):173-176
To determine whether platelet size and volume are related to one another or to platelet age, subpopulations of platelets from patients with idiopathic thrombocytopenic purpura (ITP) have been produced on the basis of density using Percoll gradients. The density distribution of platelets from patients with ITP and from patients with other forms of thrombocytopenia (thought to be nonimmune in nature) was the same as in normal controls. However, the platelets in each density subpopulation from ITP patients were increased in size. beta-thromboglobulin (beta TG) content of platelets from each patient group and the normals increased with density and tended to be higher in ITP than in normal controls. beta TG concentration per unit platelet volume and its level in plasma were similar in ITP patients and in normal controls. This suggests that the apparently normal density of ITP platelets was not a result of degranulation of large, dense platelets. Thus platelet size and density are independently determined and the increased size of platelets in immune thrombocytopenia may be the result of abnormalities in their production. 相似文献
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Large Bloody Ascites in Association with Pelvic Endometriosis: Case Report and Literature Review 总被引:1,自引:0,他引:1
Hussein M. El-Newihi M.D. Jean-Pierre Antaki M.D. Sugantha Rajan M. D. Telfer B. Reynolds M.D. 《The American journal of gastroenterology》1995,90(4):632-634
Endometriosis is only rarely the cause of massive bloody ascites. This entity simulates gynecological malignancy and is seldom recognized before surgical exploration of the abdomen. It is more commonly seen in black nulliparous females. Hormonal modulation has obviated the need for surgical resection, in some cases. We report a case of such an entity and review the medical literature. 相似文献
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Hajj Hussein IA Tohme R Barada K Mostafa MH Freund JN Jurjus RA Karam W Jurjus A 《World journal of gastroenterology : WJG》2008,14(25):4028-4039
AIM:To develop a novel model of colitis in rats, using a combination of iodoacetamide and enteropathogenic E. coli(EPEC), and to elucidate the pathophysiologic processes implicated in the development of ulcerative colitis (UC).
METHODS: Hale Sprague-Dawley rats (/7 = 158) were inoculated intrarectally on a weekly basis with 4 different combinations: (a) 1% methylcellulose (HC), (b) 100 μL of 6% iodoacetamide (IA) in 1% HC, (c) 200 p.L containing 4×10^8 colony factor units (CFU) of EPEC, and (d) combined treatment of (IA) followed by bacteria (13) after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase (HPO), and by TNF-α gene expression. RESULTS: Findings indicative of UC were seen in the combined treatment (IA + B) as well as the IA continued treatment groups: the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION: The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity. 相似文献
METHODS: Hale Sprague-Dawley rats (/7 = 158) were inoculated intrarectally on a weekly basis with 4 different combinations: (a) 1% methylcellulose (HC), (b) 100 μL of 6% iodoacetamide (IA) in 1% HC, (c) 200 p.L containing 4×10^8 colony factor units (CFU) of EPEC, and (d) combined treatment of (IA) followed by bacteria (13) after 2 d. Thirty days post treatment, each of the four groups was divided into two subgroups; the inoculation was stopped for one subgroup and the other subgroup continued with biweekly inoculation until the end of the experiment. Colitis was evaluated by the clinical course of the disease, the macroscopic and microscopic alterations, activity of myeloperoxidase (HPO), and by TNF-α gene expression. RESULTS: Findings indicative of UC were seen in the combined treatment (IA + B) as well as the IA continued treatment groups: the animals showed slow rate of increase in body weight, diarrhea, bloody stools, high colonic ulcer score, as well as histological alterations characteristic of UC, with an extensive inflammatory reaction. During the course of the experiment, the MPO activity was consistently elevated and the TNF-α gene expression was upregulated compared to the control animals.
CONCLUSION: The experimental ulcerative colitis model used in the present study resembles, to a great extent, the human disease. It is reproducible with characteristics indicative of chronicity. 相似文献