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1.
Dr. Robert L. Geggel David R. Fulton Harvey L. Chernoff Richard Cleveland Thomas J. Hougen 《Pediatric cardiology》1987,8(4):279-283
Summary An infant girl is described who had cor triatriatum and partial anomalous pulmonary venous connection of the left pulmonary
veins to the coronary sinus, the first report of this combination of lesions. The infant also had a Dandy-Walker malformation
and multiple facial and intrathoracic hemangiomas. The cardiac diagnosis was made by two-dimensional echocardiography. Cardiac
catheterization and angiography confirmed the findings and also demonstrated a persistent left superior vena cava draining
to the coronary sinus. The infant underwent successful surgical repair. Partial anomalous pulmonary venous connection and
left superior vena cava not infrequently are associated with cor triatriatum. Although two-dimensional echocardiography is
sensitive for the detection of cor triatriatum, preoperative cardiac catheterization is necessary to identify unequivocally
systemic and pulmonary venous connections. 相似文献
2.
A B Fulton J Dodge J L Schremser A Armstrong F Lanier W W Dawson T P Williams 《Current eye research》1990,9(12):1211-1216
The content of rhodopsin in the eyes of 15 donors (30 eyes) was determined. Both retinal and pigment epithelial fractions were collected from each globe, extracted using 1% CTAB, and the rhodopsin difference spectrum of each fraction was obtained separately. The total amount of rhodopsin, obtained by summing the amounts recovered from the retinal and PE fractions, ranged from 2.00 to 11.94 (median: 6.40) nmoles/eye. Previously reported mean values of about 3.5 to 4.0 nmoles per retina have been obtained using a variety of methods. The present higher values, perhaps largely dependent on procedural details described herein, appear plausible given the known concentrations of rhodopsin in rod outer segments, rod outer segment volumes, and number of rods in the human retina. 相似文献
3.
L. A. Fulton 《Canadian Medical Association journal》1997,157(5):570-572
4.
5.
Suppurative corneal ulceration in Bangladesh 总被引:8,自引:0,他引:8
AAS Dunlop MB BS ED Wright MRCPath † SA Howlader‡ I Nazrul‡ R Husain‡ K McClellan FRACO § FA Billson FRACO § 《Clinical & experimental ophthalmology》1994,22(2):105-110
Suppurative keratitis is an important preventable cause of blindness, particularly in the developing world. This study analyses 142 cases of suppurative keratitis referred to Chittagong Eye Infirmary, Bangladesh. Some 53.5% of cases were bacterial and 35.9% were fungal. The five most common pathogens were: Pseudomonas sp. 24%, Streptococcus pneumoniae 17%, Aspergillus sp. 13%, Fusarium sp. 7% and Curvularia sp. 6%. Gram stain and culture results were consistent in 62.6% of cases. Previous antibiotic treatment was a significant factor for failure of culture isolation and less so for Gram stain failure. On Gram stain, 55.9% of pseudomonal cases were missed, but only 2% of fungal cases were missed. Over all, Gram stain had a sensitivity of 62% and positive predictive value of 84% for bacterial cases, and 98% and 94% for fungal cases, respectively. Fungal ulcers were typically filamentous, but an antecedent history of trauma was not common. The most frequent injury was due to rice grains, but the inoculum appeared to be introduced during eye washing with contaminated water. Pseudomonal ulcers occurred most frequently in the monsoon season, and Fusarium cases were seen only in the hot, dry season. 相似文献
6.
7.
Percutaneous transluminal angioplasty has been shown to be both feasible and efficacious for the treatment of aortic coarctation. Recent reports, however, have indicated that the development of aortic aneurysms at or near the coarctation segment may complicate attempts to treat this lesion by catheter-based intervention. Accordingly, we examined the light microscopic features of coarctation segments excised at surgery (n = 31) or obtained at autopsy (n = 2) in 33 patients with coarctation of the aorta. Cystic medial necrosis, defined as depletion and disarray of elastic tissue, was observed in each of the 33 specimens. In the majority of coarctation specimens (22 of 33 or 67%) the extent of cystic medial necrosis, graded semiquantitatively on a scale of 0 (normal aorta) to 3+, was severe (3+). The finding that cystic medial necrosis represents a consistent histologic feature of coarctation of the aorta provides a pathologic basis for the formation of aneurysms observed after balloon angioplasty of coarctation sites. 相似文献
8.
9.
Nonheme iron in sickle erythrocyte membranes: association with phospholipids and potential role in lipid peroxidation 总被引:5,自引:0,他引:5
Previous studies documented the abnormal association of heme and heme proteins with the sickle RBC membrane. We have now examined RBC ghosts and inside-out membranes (IOM) for the presence of nonheme iron as detected by its formation of a colored complex with ferrozine. Sickle ghosts have 33.8 +/- 18.2 nmol nonheme iron/mg membrane protein, and sickle IOM have 4.3 +/- 3.0 nmol/mg. In contrast, normal RBC ghosts and IOM have no detectable nonheme iron. The combination of heme and nonheme iron in sickle IOM averages nine times the amount of membrane- associated iron in normal IOM. Kinetics of the ferrozine reaction show that some of this nonheme iron on IOM reacts slowly and is probably in the form of ferritin, but most (72% +/- 18%) reacts rapidly and is in the form of some other biologic chelate. The latter iron compartment is removed by deferoxamine and by treatment of IOM with phospholipase D, which suggests that it represents an abnormal association of iron with polar head groups of aminophospholipids. The biologic feasibility of such a chelate was demonstrated by using an admixture of iron with model liposomes. Even in the presence of tenfold excess adenosine diphosphate, iron partitions readily into phosphatidylserine liposomes; there is no detectable association with phosphatidylcholine liposomes. To examine the bioavailability of membrane iron, we admixed membranes and t-butylhydroperoxide and found that sickle membranes show a tenfold greater peroxidation response than do normal membranes. This is not due simply to a deficiency of vitamin E, and this is profoundly inhibited by deferoxamine. Thus, while thiol oxidation in sickle membranes previously was shown to correlate with heme iron, the present data suggest that lipid peroxidation is related to nonheme iron. In control studies, we did not find this pathologic association of nonferritin, nonheme iron with IOM prepared from sickle trait, high-reticulocyte, postsplenectomy, or iron-overloaded individuals. These data provide additional support for the concept that iron decompartmentalization is a characteristic of sickle RBCs. 相似文献
10.
Anne B. Fulton Ronald M. Hansen 《Documenta ophthalmologica. Advances in ophthalmology》1988,68(3-4):293-304
Scotopic b-wave stimulus/response (S/R) functions are abnormal in several human retinal degenerative disorders. However, the mechanisms by which diseases affect the S/R parameters are not yet fully known. Three experiments were done to simulate functional pathologies known to occur in retinal degenerations: 1) attenuated sensitivity of retinal units, 2) loss of rhodopsin, 3) loss of sensitivity with little or no loss of rhodopsin. None of the experimental perturbations of normal function replicated the pattern of S/R abnormalities caused by retinal degenerations. Thus, in the retinal degenerative disorders intrinsic abnormalities of cellular processing must affect the organization of distal retinal function indexed by the b-wave. 相似文献