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PURPOSE: Cryotherapy and indirect laser retinal photoablation are both effective in the treatment of retinopathy of prematurity (ROP). We describe the safety, efficiency, and effectiveness of combined cryotherapy and diode laser photocoagulation to treat threshold ROP. METHODS: Records of patients developing threshold ROP from January 1, 1996 through December 31, 1998, were retrospectively reviewed to identify those treated with combined cryotherapy and photocoagulation and followed up for at least 45 days postoperatively. Diode laser was used to ablate posterior avascular retina, and cryotherapy was used for anterior retina. Data reviewed included ocular and systemic complication rates, treatment duration, number of laser burns, most recent fundus examination, visual acuity, and refraction. RESULTS: In 13 patients, 23 eyes received combined treatment. No intraoperative complications occurred. Mean duration of anesthesia and treatment was 35 +/- 8 minutes/eye. A mean of 117 +/- 84 laser burns/eye were applied. In 20 of 23 eyes (87.0%), anatomic outcome was favorable at last examination. In 13 of 16 eyes (81.3%), functional (visual acuity) outcome was favorable (visual acuity better than 20/200) at 1 year. At 6 months or later, 14 of 16 eyes (87.5%) measured were myopic, of which 5 (31.3%) were highly myopic (> 6 diopters). CONCLUSIONS: The effectiveness of treating ROP with combined cryotherapy and diode laser photocoagulation compares with that of either modality alone. By decreasing the number of laser applications, combined therapy may be faster and technically easier for eyes with very posterior ROP. This may decrease the number of complications seen when either excessive cryotherapy or laser retinal photoablation is used. 相似文献
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In vivo microdialysis and conditioned place preference studies in rats are consistent with abuse potential of tramadol. 总被引:2,自引:0,他引:2
Jon E Sprague Michael Leifheit Jennifer Selken Michael M Milks David H Kinder David E Nichols 《Synapse (New York, N.Y.)》2002,43(2):118-121
The abuse potential of tramadol was investigated using both in vivo microdialysis measures of dopamine (DA) release within the nucleus accumbens (NAc) shell and the conditioned place preference (CPP) paradigm in rats. Tramadol (75 mg/kg, i.p.) induced a statistically significant increase (starting 80 min posttreatment) in DA release within the NAc shell, which was maintained for at least 120 min posttreatment. Tramadol (18.75, 37.5, and 75 mg/kg i.p.) produced a statistically significant CPP, with the effects of the two highest doses comparable to those induced by morphine (5 mg/kg, s.c.). The release of DA within the NAc shell may be responsible for the rewarding properties of tramadol and, together with the CPP results, provide evidence that tramadol may possess greater abuse potential than originally believed. 相似文献
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Courtenay Frazier Norbury 《J. Speech Lang. Hear. Res.》2004,47(5):1179-1193
The current investigation explored understanding of idioms in context in 93 children with communication disorders and 39 age-matched peers. The clinical group was subdivided by (a) the presence of autistic features and (b) the presence of language impairment. Idiom definitions were gathered in isolation and in context. Related skills such as semantics and theory of mind were also measured. All children benefited significantly from context. However, 2 groups with language impairments (1 with and 1 without autistic features) did not benefit from context as much as the controls or a group of children with autistic features without additional language difficulties. Regression analyses found that age, memory for story context, and language abilities were significant predictors of idioms in context performance. These findings are discussed in relation to theories of idiom acquisition and contextual processing in autism. 相似文献
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1. In agreement with previous work, we have found that the ipsilateral visual field is represented in an extensive rostral portion--from one-third to one-half--of the superior colliculus (SC) of the cat. This representation is binocular. The SC representation of the ipsilateral visual field can be mediated both directly, by crossed retinotectal connections originating from temporal hemiretina, and indirectly, by across-the-midline connections relaying visual information from one-half of the brain to contralateral SC. 2. In order to study the indirect, across-the-midline visual input to the SC, we have recorded responses of SC neurons to visual stimuli presented to either the ipsilateral or the contralateral eye of cats with a midsagittal splitting of the optic chiasm. Units driven by the ipsilateral eye, presumably through the direct retinotectal input and/or corticotectal connections from ipsilateral visual cortex, were found throughout the SC, except at its caudal pole, which normally receives fibers from the extreme periphery of the contralateral nasal hemiretina. Units driven by the contralateral eye, undoubtedly through an indirect across-the-midline connection, were found only in the anterior portion of the SC, in which is normally represented the ipsilateral visual field. Receptive fields in both ipsilateral and contralateral eye had properties typical of SC receptive fields in cats with intact optic pathways. 3. All units having a receptive field in the contralateral eye had also a receptive field in the ipsilateral eye; for each of these units, the receptive fields in both eyes invariably abutted the vertical meridian of the visual field. The receptive field in one eye had about the same elevation relative to the horizontal meridian and the same vertical extension as the receptive field in the other eye; the two receptive fields of each binocular unit matched each other at the vertical meridian and formed a combined receptive field straddling the vertical midline of the horopter... 相似文献
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Dorothy V M Bishop Caroline V Adams Courtenay Frazier Norbury 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2004,(1):94-96
This study considered whether cognitive profile could distinguish groups of children where genes or environment played a major role in influencing reading level. Same-sex twin pairs from an epidemiological study were categorized according to parental report at 4 years of age into those with low language skills and a typically developing group. A total of 132 same-sex twin pairs from the low language group and 66 from the control group were assessed at 6 years of age, to investigate heritability of reading ability adjusted for nonverbal IQ. For pairs where both twins had normal scores on a nonword repetition test, heritability was zero, with environmental influences explaining all the variance. For pairs where one or both twins had low nonword repetition, the heritability estimate was 0.79 and the variance due to shared environment was zero. Future studies of genetics of reading development should treat those with poor nonword repetition skills as a separate subgroup. 相似文献
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The Jansen type of metaphyseal dysplasia is a rare disorder with significant clinical and radiographic variability. Two cases of classical Jansen disease and one with some distinctive features suggestive of the Jansen variant are reported. 相似文献