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101.
Al-Khayer K Hagstrom S Pauer G Zegarra H Sears J Traboulsi EI 《American journal of ophthalmology》2004,137(2):375-377
PURPOSE: To present long-term follow-up on a North American patient with Leber congenital amaurosis (LCA) and novel compound heterozygous mutations in the RPE65 gene. DESIGN: Case report. METHODS: RPE65 mutation screening and search for sequence changes using Single Strand Conformation Polymorphism and direct DNA sequencing. Ophthalmic examination and electrophysiologic testing. RESULTS: A 35-year-old female carried two RPE65 mutations: a maternal 961A>T (K303X) nonsense mutation and a paternal 1346A>G (Y431C) missense mutation. She had severe visual deficits and an absence of rod and cone Electroretinogram responses. Visual acuity of 20/60 both eyes and normal color recognition during early childhood declined to 2/200 in the right eye and 1/200 in the left eye at the age of 35. CONCLUSIONS: The RPE65 mutations K303X and Y431C in compound heterozygous form cause progressive visual compromise that starts in childhood and advances to severe visual loss by the fourth decade of life. 相似文献
102.
Clinicopathologic study after submacular removal of choroidal neovascular membranes treated with verteporfin ocular photodynamic therapy 总被引:3,自引:0,他引:3
Moshfeghi DM Kaiser PK Grossniklaus HE Sternberg P Sears JE Johnson MW Ratliff N Branco A Blumenkranz MS Lewis H 《American journal of ophthalmology》2003,135(3):343-350
PURPOSE: To report the clinicopathologic findings after submacular removal of choroidal neovascular membranes (CNV) treated with verteporfin ocular photodynamic therapy. DESIGN: Interventional case series. METHODS: Retrospective review of eight eyes of eight patients who underwent submacular surgery for CNV after having previously received verteporfin ocular photodynamic therapy for presumed ocular histoplasmosis (one patient), age-related macular degeneration ([AMD] three patients) pathologic myopia (two patients), punctate inner choroiditis (one patient), and idiopathic CNV (one patient). All cases had undergone ocular photodynamic therapy with verteporfin using standard protocols. Six of eight patients suffered a submacular hemorrhage after ocular photodynamic therapy, and two of eight patients refused further ocular photodynamic therapy. All patients subsequently had submacular surgery with removal of the CNV. One membrane was routinely processed, sectioned, and stained with hematoxylin and eosin. Five membranes were stained with toluidine blue for light microscopic examination. Semithin (1.0 microm) sections were cut and stained with uranyl acetate-lead citrate for transmission electron microscopy. RESULTS: Choroidal neovascular membranes were removed at 3 days (presumed ocular histoplasmosis), 29 days (punctate inner choroiditis), 63 days (AMD, pathologic myopia), 66 days (AMD), 107 days (pathologic myopia), 116 days (AMD), and 152 days (idiopathic) after verteporfin ocular photodynamic therapy. Histopathologic and ultrastructural examination showed areas of vascular occlusion at 3 days that were not seen at later time points. All specimens had patent CNV. There were signs of vascular damage with extravasated erythrocytes and fibrin, pigment clumping in cells, and inflammatory cells in all but the 3-day specimen.CONCLUSIONS: This case series presents data only from patients who refused repeat treatment with ocular photodynamic therapy or who developed submacular hemorrhage after initial photodynamic therapy. Histopathologic evaluation of CNV 3 days after verteporfin ocular photodynamic therapy showed partial vascular occlusion that was not present in later specimens. These later specimens demonstrated evidence of vascular damage. Verteporfin ocular photodynamic therapy does not appear to lead to permanent and complete occlusion of the CNV. Thus, treatments that lead to permanent closure of CNV without damage to the retinal pigment epithelium and sensory retina are still needed. 相似文献
103.
Vallières E Gonzalez X Pedersen KM Sears GK Springmeyer SC 《The Annals of thoracic surgery》2003,76(6):2071-2074
PURPOSE: This study assessed the feasibility of using the VALR surgical system (Spiration Inc, Redmond, WA), limited by federal law to investigational use, for capturing and reducing a selected portion of affected lobes in patients undergoing lobectomy. DESCRIPTION: The tested system consists of a hand-held vacuum-regulated introducer loaded with a flexible, silicone sleeve. Targeted tissue is drawn into the introducer and the silicone sleeve is deployed and sutured in place. The end of the proximal sleeve includes a compression band for applying uniform radial pressure, suture ports, and silicone lugs lining the inner lumen for reinforcing sleeve position. EVALUATION: The system was effective in capturing 25% to 30% tissue of each lobe tested. Mean intraoperative test time was 8.5 minutes. The compression sleeve did not slip or dislodge after suturing, and no tissue damage or leaks were observed. CONCLUSIONS: It was feasible using vacuum to draw and isolate a portion of pulmonary tissue within a silicone sleeve. The system was intuitive to apply, easy to use, and produced effective reduction and sealing of tissue. 相似文献
104.
Williams PD Ducey KA Sears AM Williams AR Tobin-Rumelhart SE Bunde P 《International journal of nursing studies》2001,38(3):359-367
Oncology patients receiving chemotherapy (n=109) and radiation therapy RT (n=161) reported symptom concerns and severity on the 25-item therapy-related symptom checklist (TRSC). Secondary analysis of the self-reports of the two treatment groups was done using the Mann-Whitney U Test. Thirteen symptoms differed significantly between the two groups. RT patients reported significantly greater severity of five symptoms (p<0.05) during therapy. Chemotherapy patients reported significantly greater severity of eight different symptoms. The other 14 items showed a heterogeneous pattern of self-reported patient symptom concerns. The TRSC appears to be a clinically useful self-report checklist that captures the more important symptom concerns of both RT and chemotherapy patients. Earlier efforts to develop this checklist are reviewed briefly. 相似文献
105.
Sears MR 《Pediatric pulmonology》2001,31(4):327; author reply 328
106.
Occupational stressors, coping strategies, and burnout and depression were examined in extension agents. Results indicated that a significant proportion of extension agents (range = 9.8%-51%) reported burnout symptoms above established cut-off scores for the burnout subscales, but fewer than 3% of the sample reported significant symptoms on all 3 dimensions of burnout. Depressive symptoms based on established cut-off scores were noted in approximately 26% of the sample. Stepwise multiple regression indicated that extension agents who used an emotion-oriented coping strategy were more likely to (a) display high levels of depression, emotional exhaustion, and depersonalization and (b) exhibit low levels of personal accomplishment. Furthermore, task-oriented coping strategies were found to be negatively associated with the 3 dimensions of burnout. Implications for interventional programming to reduce the symptoms of burnout are discussed. 相似文献
107.
Diversity of odourant binding proteins revealed by an expressed sequence tag project on male Manduca sexta moth antennae 总被引:11,自引:0,他引:11
Robertson HM Martos R Sears CR Todres EZ Walden KK Nardi JB 《Insect molecular biology》1999,8(4):501-518
A small expressed sequence tag (EST) project generating 506 ESTs from 375 cDNAs was undertaken on the antennae of male Manduca sexta moths in an effort to discover olfactory receptor proteins. We encountered several clones that encode apparent transmembrane proteins; however, none is a clear candidate for an olfactory receptor. Instead we found a greater diversity of odourant binding proteins (OBPs) than previously known in moth antennae, raising the number known for M. sexta from three to seven. Together with evidence of seventeen members of the family from the Drosophila melanogaster genome project, our results suggest that insects may have many tens of OBPs expressed in subsets of the chemosensory sensilla on their antennae. These results support a model for insect olfaction in which OBPs selectively transport and present odourants to transmembrane olfactory receptors. We also found five members of a family of shorter proteins, named sensory appendage proteins (SAPs), that might also be involved in odourant transport. This small EST project also revealed several candidate odourant degrading enzymes including three P450 cytochromes, a glutathione S-transferase and a uridine diphosphate (UDP) glucosyltransferase. Several first insect homologues of proteins known from vertebrates, the nematode Caenorhabditis elegans, yeast and bacteria were encountered, and most have now also been detected by the large D. melanogaster EST project. Only thriteen entirely novel proteins were encountered, some of which are likely to be cuticle proteins. 相似文献
108.
Singular value decomposition with self-modeling applied to determine bacteriorhodopsin intermediate spectra: analysis of simulated data
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Zimányi L Kulcsár A Lanyi JK Sears DF Saltiel J 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(8):4408-4413
An a priori model-independent method for the determination of accurate spectra of photocycle intermediates is developed. The method, singular value decomposition with self-modeling (SVD-SM), is tested on simulated difference spectra designed to mimic the photocycle of the Asp-96 --> Asn mutant of bacteriorhodopsin. Stoichiometric constraints, valid until the onset of the recovery of bleached bacteriorhodopsin at the end of the photocycle, guide the self-modeling procedure. The difference spectra of the intermediates are determined in eigenvector space by confining the search for their coordinates to a stoichiometric plane. In the absence of random noise, SVD-SM recovers the intermediate spectra and their time evolution nearly exactly. The recovery of input spectra and kinetics is excellent although somewhat less exact when realistic random noise is included in the input spectra. The difference between recovered and input kinetics is now visually discernible, but the same reaction scheme with nearly identical rate constants to those assumed in the simulation fits the output kinetics well. SVD-SM relegates the selection of a photocycle model to the late stage of the analysis. It thus avoids derivation of erroneous model-specific spectra that result from global model-fitting approaches that assume a model at the outset. 相似文献
109.
Intermediate spectra and photocycle kinetics of the Asp96 --> asn mutant bacteriorhodopsin determined by singular value decomposition with self-modeling
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Zimányi L Kulcsár A Lanyi JK Sears DF Saltiel J 《Proceedings of the National Academy of Sciences of the United States of America》1999,96(8):4414-4419
Singular value decomposition with self-modeling is applied to resolve the intermediate spectra and kinetics of the Asp96 --> Asn mutant bacteriorhodopsin. The search for the difference spectra of the intermediates is performed in eigenvector space on the stoichiometric plane. The analysis of data at pH values ranging from 4 to 8 and temperatures between 5 and 25 degrees C reveals significant, early partial recovery of the initial state after photoexcitation. The derived spectra are not biased by assumed photocycles. The intermediate spectra derived in the initial step differ from spectra determined in prior analyses, which results in intermediate concentrations with improved stoichiometric properties. Increasingly more accurate photocycles follow with increasing assumed complexity, of which parallel models are favored, consistent with recent, independent experimental evidence. 相似文献
110.
A technique to harvest, intrapleurally route, and anastomose the left internal mammary artery is described. 相似文献