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PURPOSE: Flavonoids with two to five hydroxy groups, with or without sugar, and/or methoxy groups were studied on their effects to affect ocular blood flow. METHODS: Colored microsphere technique was used to determine the ocular blood flow in rabbit eyes. RESULTS: Flavonoids with three free hydroxy (OH) groups seemed to produce the optimal effects in increasing ocular blood flow (naringenin and hesperitin, Pfalts and Bauer, Waterbury, CT). Whether the OH groups are below three (naringenin, hesperitin, Pfalts and Bauer, Waterbury, CT) or above four (Quercetin, Pfalts and Bauer, Waterbury, CT), they produced no effects on the ocular blood flow. When OH groups are four (rutin, Aldrich, Milwaukee, WI), it produced mixed effects on ocular blood flow. The attachment of rutinose and/or methoxy group in the structure did not affect the ocular blood flow one way or the other. CONCLUSION: The ocular blood flow is increased significantly by the number of OH group in the molecule, with three the best to increase the ocular blood flow.  相似文献   
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PURPOSE: The Rodenstock scanning laser ophthalmoscope (SLO) is useful for mapping retinal function and for developing and evaluating visual rehabilitation methods. It is essential to know the visual angle subtended by stimuli in the SLO laser-beam raster and to accurately measure angular distances between objects in the final SLO image. To accomplish this, the angular extent of the SLO laser-beam raster must be calibrated. METHODS: We developed a simple method and apparatus for calibrating the raster and used it for repeated calibrations during a 3-month period. RESULTS: The laser-beam raster is quite stable in shape and size, but it is trapezoidally distorted in the vertical direction. Consequently, SLO images are distorted. CONCLUSIONS: Trapezoidal distortion of the SLO laser-beam raster can cause stimulus size to change as much as 10% from the top to the bottom of the raster. Measurements of fixed horizontal retinal landmark distances in SLO images can also vary as much as 10%. We developed a straightforward mathematical method for correcting distortion in SLO image measurements.  相似文献   
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OBJECTIVE: The authors described the influence of specific medical conditions on clinical remission and response of major depression (MDD) in a clinical trial evaluating a care-management intervention among older primary-care patients. METHODS: Adults age 60 years and older were randomly selected and screened for depression. Participants were randomly assigned to Usual Care or to an Intervention with a depression care-manager offering algorithm-based care for MDD. In all, 324 adults meeting criteria for MDD were included in these analyses. Remission and response was defined by a score on the Hamilton Rating Scale for Depression <10 and by a decrease from baseline of > or =50%, respectively. Medical comorbidity was ascertained through self-report. Cognitive impairment was defined by a score <24 on the Mini-Mental State Exam (MMSE). RESULTS: In Usual Care, rates of remission were faster in persons who reported atrial fibrillation (AF) than in persons who did not report AF and slower in persons who reported chronic pulmonary disease than in persons who did not report chronic pulmonary disease; rates of response were less stable in persons with MMSE <24 than in those with MMSE > or =24. In the Intervention condition, none of the specific chronic medical conditions were significantly associated with outcomes for MDD. CONCLUSIONS: Because disease-specific findings were observed in persons who received Usual Care but not in persons who received more intensive treatment in the Intervention condition, our results suggest that the association of medical comorbidity and treatment outcomes for MDD may be determined by the intensity of treatment for depression.  相似文献   
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