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11.
Tumor-associated retinal pigment epithelial proliferation simulating retinal pigment epithelial tear
A lesion with both the clinical and fluorescein angiographic appearance of the classical retinal pigment epithelial (RPE) tear was discovered over the dome of an actively growing metastatic choroidal tumor in a patient with a previous history of breast carcinoma. However, our patient exhibited no evidence of pigment epithelial detachment or age-related macular degeneration, the underlying cause of the RPE tear. Although we cannot be sure that a true RPE tear did not exist over our patient's tumor, more likely, we are observing a tumor induced zone of RPE dehiscence accompanied by RPE proliferation at its border, giving a very similar fundus appearance. Possible pathogenic mechanisms for the finding in our patient, and a comparison to those mechanisms responsible for the classical RPE tear, are discussed. 相似文献
12.
Objective. To determine the stability of an admixture combining ziconotide with bupivacaine hydrochloride during simulated intrathecal infusion under laboratory conditions at 37°. Materials and Methods. An admixture containing ziconotide (25 µg/mL) and bupivacaine hydrochloride (5 mg/mL) was stored in SynchroMed® II pumps at 37° and in control vials at either 37° or 5°. Using high‐performance liquid chromatography, drug concentrations were determined from samples obtained at varying intervals during the 30‐day study. Results. After 30 days, pump ziconotide and bupivacaine hydrochloride concentrations measured an average of 86.9% and 99.4% of their initial concentrations, respectively. Control vials displayed similar degradation rates for both drugs. Statistical evaluation of the ziconotide 95% confidence interval indicated that the ziconotide concentration would meet or exceed 90% and 80% of initial concentration for 22 days and 45 days, respectively. Conclusions. An admixture containing 25 µg/mL ziconotide and 5 mg/mL bupivacaine hydrochloride was 90% stable for 22 days and 80% stable for 45 days (extrapolated) in SynchroMed® II infusion pumps. 相似文献
13.
Cytochrome P450IIE1 genetic polymorphisms, racial variation, and lung cancer risk. 总被引:10,自引:0,他引:10
S Kato P G Shields N E Caporaso R N Hoover B F Trump H Sugimura A Weston C C Harris 《Cancer research》1992,52(23):6712-6715
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Navajo birth outcomes in the Shiprock uranium mining area. 总被引:2,自引:0,他引:2
The role of environmental radiation in the etiology of birth defects, stillbirths, and other adverse outcomes of pregnancy was evaluated for 13,329 Navajos born at the Public Health Service/Indian Health Service Hospital in the Shiprock, NM, uranium mining area (1964-1981). More than 320 kinds of defective congenital conditions were abstracted from hospital records. Using a nested case-control design, families of 266 pairs of index and control births were interviewed. The only statistically significant association between uranium operations and unfavorable birth outcome was identified with the mother living near tailings or mine dumps. Among the fathers who worked in the mines, those of the index cases had histories of more years of work exposure but not necessarily greater gonadal dosage of radiation. Also, birth defects increased significantly when either parent worked in the Shiprock electronics assembly plant. Overall, the associations between adverse pregnancy outcome and exposure to radiation were weak and must be interpreted with caution with respect to implying a biogenetic basis. 相似文献
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In a comparative trial, 21 patients (mean age 43 (range 19-66) years) with dilated upper urinary tracts underwent diuresis renography with both 123I-hippuran and the experimental agent. 99Tcm-thiodiglycolic acid (TDG). Deconvolution analysis of the derived renograms was also performed and the transit times were calculated. Excellent agreement was found between results with the two radiopharmaceuticals. There was complete agreement in interpretation of the response to diuresis with both agents and 84% agreement in the transit time estimations. Good images were produced with both agents and 99Tcm-TDG is considered to be a useful alternative to 123I-hippuran. 相似文献
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R Glousman C Shields R Kerlan F Jobe S Lombardo L Yocum J Tibone R Gambardella 《The American journal of sports medicine》1988,16(4):321-326
Reconstruction for symptomatic anterior cruciate deficient knees has yielded varying success rates. Prosthetic cruciate replacement has recently become a potentially attractive alternative. The results of the Gore-Tex polytetrafluoroethylene ligament, which is intended as a permanent replacement, are reported. Eighty-two patients were followed prospectively, mean age was 28 years (range, 16 to 51 years) and mean followup was 18 months (range, 12 to 30 months). Subjective scores improved in all categories, including pain, swelling, giving way, locking, and stair climbing. All patients without complications had no episodes of actual giving way, considered themselves improved, and returned to activities of daily living at 3 weeks and athletics at 8 months. Range of motion lacking at 3 months was 2 degrees of extension and 10 degrees of flexion, and at 12 months was 0 degrees of extension and 4 degrees of flexion. All mean objective data, including the anterior drawer, Lachman, and pivot shift, demonstrated improvement at final followup. Cybex testing revealed improvement in relative quadriceps strength from 88% to 99%. The KT-1000 Arthrometer showed improvement in the injured-normal knee difference score throughout the follow-up period. Of importance is that while final objective data was improved over initial data, an early nonprogressive shift toward loosening was indicated by worsening of the drawer, Lachman, pivot shift, and KT-1000 scores. This shift may be attributed to resorption of interposed soft tissue, creep, or loosening of the graft. Subjective scores remained stable after improving. Complications included four ruptures, four chronic sterile effusions with partial attenuation, one infection, and one symptomatic loose body.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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