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51.
François Béïque Mohamed Ali Scott MacKenzie Mark Hynes 《Journal canadien d'anesthésie》2007,54(2):158-159
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53.
Mohamed Eid Fawzy Mohamed Shoukri Walid Hassan Vijayaraghavan Nambiar Miltiadis Stefadouros Charles C Canver 《Catheterization and cardiovascular interventions》2007,69(1):40-46
BACKGROUND: The effect of mitral valve morphology (MVM) on the long-term results of mitral balloon valvuloplasty (MBV) is not well established. The aim of the study was to evaluate the impact of MVM on long-term outcome of MBV. METHODS: Five hundred and eighteen consecutive patients (mean age, 31+/-11 years) who underwent successful MBV were followed up for 0.5-16.5 (mean, 6+/-4.5) years. Patients were divided into two groups according to their mitral echo score (MES) before MBV: group A (n=340; MES8). RESULTS: We report the immediate and long-term clinical and echocardiographic results of the above-mentioned 518 consecutive patients. The mitral valve area was significantly larger in group A than in group B, both immediately after MBV (2.0+/-0.3 vs. 1.82+/-0.3 cm2, respectively; P<0.0001) and also at the last follow-up (1.8+/-0.33 vs. 1.5+/-0.33 cm2, respectively; P<0.0001). Restenosis occurred in 38/340 (11%) in group A vs. 73/178 (41%) in group B (P<0.0001). Actuarial freedom from restenosis at 5, 10, 15 years were 92+/-2%, 85+/-3%, 65+/-6% for group A vs. 72+/-4%, 44+/-5%, 9+/-6% for group B (P<0.001). Event-free survival rates at 5, 10, 15 years for group A were 93+/-1%, 88+/-2%, 66+/-6% vs. 82+/-3%, 59+/-6%, 8+/-7% for group B (P<0.0001). Stepwise Cox multivariate regression analysis identified MES, preprocedure functional class, and postprocedure mitral valve area相似文献
54.
Hassan Chamsi-Pasha Alaa Abdulmoneim Waqar H Ahmed Khaled F Al-Shaibi Aref Ajam Hassan Bakhamees Abdullah K Ashmeg 《Journal of the American Society of Echocardiography》2004,17(1):70-72
A 24-year-old man presented with a 24-hour history of pain and numbness in his left arm. The patient's clinical presentation of peripheral embolism was corroborated by angiography. Echocardiographic study showed masses in both right and left atria. Pathologic specimen from the embolus confirmed the diagnosis of aspergillosis. 相似文献
55.
Andr Mas Hassan Jaaba Franois Schu Anna M. Belu Camille M. Kassis Richard W. Linton Joseph M. Desimone 《Macromolecular chemistry and physics.》1997,198(11):3737-3752
Homogeneous and stable layers were deposited through allylamine plasma polymerization (75 W, 100 Pa, 15 min) onto poly[(3-hydroxybutyric acid)-co-(3-hydroxyvaleric acid)] (91 : 9 wt.-%) (P(HB-co-9%HV)) film surfaces, XPS analysis using take-off angles of 20° and 70° and performed 10 days and 20 days after plasma treatment gives information on the composition (in atom%) of the modified surface: C, 62.74; N, 19.60; O, 17.65. The unexpected oxygen percentage is weaker if argon plasma pretreatment (25 W, 40 Pa, 5 min) is applied. Then, a succinct mechanism is proposed. The study of changes in element ratios and binding energy values shows that the majority of incorporated functional groups seem to be amide and imine groups. 相似文献
56.
Fumitaka Nakamura Jan Kvasnicka Micheline Levame Franoise Lange Hassan Bousbaa Herbert J. Geschwind 《Lasers in surgery and medicine》1993,13(4):412-420
This study was designed to examine the acute response of normal arterial wall to pulsed laser irradiation. Irradiation with an Excimer or a Holmium YAG laser was performed in 15 normal iliac sites of 8 male New Zealand white rabbits. The excimer laser was operated at 308 nm, 25 Hz, 50 mj/mm2/pulse, and 135 nsec/pulse and the Ho:YAG laser was operated at 2.1 μm, 3.5 Hz, 400 mj/ pulse, 250 μsec/pulse. The excimer and Ho:YAG laser were coupled into a multifiber wire-guided catheter of 1.4 and 1.5 mm diameter, respectively. The mean luminal diameter increased similarly from 2.01 ± 0.29 to 2.46 ± 0.27 mm (P < 0.0005) and from 2.09 ± 0.53 to 2.45 ± 0.30 mm (P < 0.005) after excimer and Ho:YAG laser irradiation, respectively. Perforation occurred in 3 of 15 Ho:YAG irradiated sites and 0 of 15 excimer laser irradiated sites. The sites irradiated with excimer or Ho:YAG laser had similar histologic features, consisting of shedding of the endothelium, disorganization of internal elastic lamina, localized necrosis of vascular smooth muscle cells, and fissures in the medial layer. However, the sites irradiated with excimer laser had lower grading scores than those irradiated with the Ho:YAG laser (P<0.05). Irradiation with excimer or Ho:YAG laser of normal arteries results in: (1) vasodilation of the irradiated artery; (2) localized mechanical vascular injury, and (3) Ho:YAG laser induces more severe damage to the arterial wall than excimer. © 1993 Wiley-Liss, Inc. 相似文献
57.
58.
M. O. Hassan O. T. Al Shafie W. J. Johnston 《Clinical physiology and functional imaging》1993,13(5):519-523
Summary. Eleven normotensive diabetics with noninsulin-dependent diabetes mellitus (NIDDM) (mean age 52.5 SD 8.2 years) and 11 controls (mean age 47.4 SD 8.9 years) had their ambulatory blood pressure and heart rate recorded non-invasively by the Oxford Medilog System in standard hospital conditions. The results were averaged as hourly means of systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial blood pressure (MAP), and heart rate (HR) for the 24-h period and similarly for the ‘awake’ period (14.16 h) and the ‘asleep’ period (8–10 h). Hourly means for diabetics and controls showed no differences in blood pressure and heart rate over the 24 h. During sleep, control subjects showed a significant drop in SBP (P < 0.001), DBP (P < 0.001), MAP (P < 0.001) and HR (P < 0.001). However, this nocturnal dip in blood pressure could not be demonstrated in the diabetic group. Blood pressure variability was significantly increased in diabetics compared to controls during waking hours (P < 0.01). These results indicate that in noninsulin-dependent diabetics during sleep there is loss of the nocturnal dip of BP seen in normal subjects, and they have increased BP variability. These may be contributing factors to the development of hypertension and the accelerated target organ damage (TOD) seen in diabetes., 相似文献
59.
M. Q. Hassan S. A. Hussain M. A. Zaki N. Z. Alsharif S. J. Stohs 《Basic & clinical pharmacology & toxicology》1995,77(6):407-411
Abstract: The effects of uraemias and antioxidant therapy for 40 days with vitamin A, vitamin C and vitamin E on blood and erythrocyte sulfhydryl (glutathione, GSH) content and on erythrocyte glutathione-S transferase (GST), glutathione reductase (GSR) and glutathione peroxidase activities were studied in six uraemic patients maintained on haemodialysis. In addition, the effect of antioxidant therapy on erythrocyte lipid peroxidation was determined, and erythrocyte haemoglobin content was measured. Uraemic patients in dialysis exhibited significant decreases in blood and erythrocyte GSH content as well as significant decreases in the activities of GST, GSR and GSH-peroxidase relative to control subjects. Furthermore, the uraemic patients had elevated erythrocyte malondialdehyde levels. Blood and erythrocyte GSH content from uraemic patients was significantly elevated after 20 days of antioxidant treatment and remained elevated thereafter throughout the remaining 20 days of the study (130% and 173%, respectively). Antioxidant therapy also produced significant increases in GSR and GSH-peroxidase activities after 20 days of treatment which remained relatively constant thereafter. No significant change in GST activity was observed. Erythrocyte malondialdehyde levels, as an index of oxidative tissue damage, exhibited a significant decrease (70%) in the patients after 40 days of antioxidant therapy. A gradual increase in erythrocyte haemoglobin content was observed following treatment of the uraemic subjects (45% at day 40). The results suggest that antioxidant therapy may protect against oxidative stress associated with uraemia. 相似文献
60.
Simon Vinitski Carlos Gonzalez Feroze Mohamed Tad Iwanaga Robert L. Knobler Kamil Khalili John Mack 《Magnetic resonance in medicine》1997,37(3):457-469
Our aim was to develop an accurate multispectral tissue segmentation method based on 3D feature maps. We utilized proton density (PD), T2-weighted fast spin-echo (FSE), and T1-weighted spin-echo images as inputs for segmentation. Phantom constructs, cadaver brains, an animal brain tumor model and both normal human brains and those from patients with either multiple sclerosis (MS) or primary brain tumors were analyzed with this technique. Initially, misregistration, RF inhomogeneity and image noise problems were addressed. Next, a qualified observer identified samples representing the tissues of interest. Finally, k-nearest neighbor algorithm (k-NN) was utilized to create a stack of color-coded segmented images. The inclusion of T1 based images, as a third input, produced significant improvement in the delineation of tissues. In MS, our 3D technique was found to be far superior to that based on any combination of 2D feature maps (P < 0.001). We identified at least two distinctly different classes of lesions within the same MS plaque, representing different stages of the disease process. Further, we obtained the regional distribution of MS lesion burden and followed its changes over time. Neuropsychological aberrations were the clinical counterpart of the structural changes detected in segmentation. We could also delineate the margins of benign brain tumors. In malignant tumors, up to four abnormal tissues were identified: 1) a solid tumor core, 2) a cystic component, 3) edema in the white matter, and 4) areas of necrosis and hemorrhage. Subsequent neurosurgical exploration confirmed the distribution of tissues as predicted by this analysis. 相似文献