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排序方式: 共有335条查询结果,搜索用时 15 毫秒
1.
Recurrence of posterior uveal melanoma after 60Co episcleral plaque therapy   总被引:3,自引:0,他引:3  
The authors analyzed the clinical and follow-up data on 277 selected patients with primary choroidal or ciliochoroidal melanoma who were treated with 60Co plaque radiotherapy between 1976 and 1982. Local recurrence of the irradiated melanoma developed in 39 (14%) patients during the follow-up interval. The 5-year tumor recurrence rate (Kaplan-Meier) was estimated to be 12%. Multivariate prognostic factor analysis (Cox proportional hazards modeling) identified the largest linear tumor dimension and proximity of the posterior margin of the tumor to the optic nerve head as predictors of recurrence. The 5-year survival rate of patients whose tumors recurred (58%) was significantly (log-rank test P = 0.0023) worse than that of patients whose tumor remained clinically controlled (82%).  相似文献   
2.
A New Approach to an Old Problem   总被引:2,自引:0,他引:2  
A patient with progressive visual loss was found to have an optic nerve sheath meningioma. The patient was treated with stereotactic radiotherapy, a computer-guided stereotactic technique that minimizes the risk of radiation-induced optic neuropathy. Six months after treatment, the patient was doing well and showed no signs of radiation-induced optic neuropathy.  相似文献   
3.
AIMS: To evaluate the outcome of filtering procedures supplemented with mitomycin C in children with glaucoma. METHODS: All patients aged 17 or younger with glaucoma who underwent filtering surgery supplemented with mitomycin C at a tertiary care centre (n = 21) during a 5 year interval (1992 and 1996) were included. One eye for each patient was entered into the analysis. The postoperative intraocular pressure (IOP), use of antiglaucoma medications, clinical stability of glaucoma, complications, and visual acuity were retrospectively evaluated. Kaplan-Meier survival curves were used to estimate the probability of success. RESULTS: At the time of surgery mean age was 5.7 (SD 5.0) years. The most common diagnoses were trabeculodysgenesis (n = 6) and aphakic glaucoma (n = 8). Mean IOP before surgery was 35.7 (10.5) mm Hg. Average length of follow up was 18.6 (14.7) months. The probability of having IOP less than 21 mm Hg with no antiglaucoma medications and with clinically stable glaucoma 1 year after surgery was 76.9% in phakic eyes (n = 13) and 0% in aphakic eyes (n = 8). A phakic patient with Sturge-Weber's syndrome had choroidal effusion after surgery that resolved spontaneously. In the aphakic group one patient had retinal detachment and another developed an encapsulated bleb. Visual acuity deteriorated in one patient. CONCLUSION: A guarded filtration procedure with mitomycin C is relatively successful in phakic children with glaucoma, but unsuccessful in aphakic ones.  相似文献   
4.
Twenty-one patients with a circumscribed choroidal hemangioma in one eye were followed for various intervals ranging from three years to over nine years after diagnosis. Eighteen of the 21 were treated with xenon arc and/or argon laser photocoagulation to the hemangioma in an attempt to reduce or eliminate a secondary retinal detachment at some point during the follow-up period. Only four of the 21 had visual acuity of 6/12 or better in the involved eye at the time of the most recent follow-up, and 15 of the 21 had visual acuity of 6/60 or worse. Persistent nonrhegmatogenous retinal detachment involving the fovea and degenerative changes in the macular retina secondary to prior retinal detachment accounted for most of the visual impairment in these 21 eyes.  相似文献   
5.
In a 63-year-old white man with a history of long-term use of systemic corticosteroids for polyarteritis nodosa, progressive clouding of vision in the right eye developed over a 2-month period. Cytologic analysis of a fine-needle aspiration biopsy of a solitary fluffy retinovitreal mass demonstrated Cryptococcus neoformans. Subsequent cerebrospinal fluid cultures were also positive for C. neoformans. Systemic antifungal therapy was given using amphotericin-B and 5-fluorocytosine. Proliferative vitreoretinopathy developed in the right eye within 8 months. Three small yellow retinal lesions, which later resolved, developed in the fellow eye.  相似文献   
6.
The treatment of primary intraocular malignancy   总被引:1,自引:0,他引:1  
This paper will summarize much of the information derived in an association between The Department of Radiation Oncology of Hahnemann University Hospital and the Oncology Service of Wills Eye Hospital of Thomas Jefferson University, a collaborative effort for the treatment of primary intraocular malignancies that has spanned the last dozen years. In that time we have treated malignant intraocular melanoma by radioactive eyeplaque brachytherapy and have begun to develop a similar program for treatment of recurring retinoblastoma. These experiences will be described.  相似文献   
7.
Conventional highly compactible fillers such as microcrystalline cellulose (MCC) can be mixed with drug-loaded membrane-coated beads and compressed to form a tablet. However, due to particle size differences, there is substantial risk of segregation leading to weight variation and content uniformity problems. Furthermore, whenever modified release beads are included in a tablet matrix, care must be taken to assure the integrity of the coated beads. This paper describes the development of placebo beads containing MCC whose properties make them uniquely suitable for tableting modified release beads. These placebo beads have high compactibility and the ability to rapidly disintegrate. They deform readily and may provide a high degree of protection to drug-loaded membrane-coated beads during compression ('cushioning effect'). They can be produced in size ranges that provide minimal segregation propensity. Beads containing different MCC/lactose ratios and different types and levels of superdisintegrants were produced by extrusion-spheronization followed by freeze drying. The presence of high levels of MCC and different superdisintegrants, especially croscarmellose sodium, increased the granulation liquid requirement, thus producing freeze-dried beads with higher porosities and compactibility. Athy-Heckel analysis studies revealed that beads rich in MCC exhibited lower mean yield pressures than those containing high levels of lactose. The freeze-dried beads exhibited both plastic deformation and brittle fracture characteristics.  相似文献   
8.
Purpose To describe the topographical distribution of typical congenital hypertrophy of retinal pigment epithelium (CHRPE) lesions in the ocular fundi. Methods Retrospective review of the clinical records of 52 patients with typical unifocal CHRPE. Results The 52 CHRPE lesions ranged from 2.5 mm to 11.5 mm in maximal basal diameter (mean=6.6 mm, SD=2.6 mm). The central point of the lesion was in the peripheral fundus in 44 eyes and in the intermediate fundus in eight eyes. The footprint of the lesion involved the peripheral fundus only in 25 eyes, both the intermediate and peripheral fundus in 22 eyes, and the intermediate fundus only in five eyes. The central point of the lesion was located in the temporal quadrant in 24 eyes, the inferior quadrant in 12 eyes, the nasal quadrant in nine eyes, and the superior quadrant in seven eyes. No lesion in this series involved the posterior fundus. Conclusions The most common fundus location for typical unifocal CHRPE in this series was the peripheral fundus temporally. Although posterior fundus location of CHRPE has been reported occasionally, our study suggests that such a location is very uncommon.  相似文献   
9.
Uveal melanomas are rare in black patients. Of a total of 2586 patients with the diagnosis of posterior uveal melanoma who were managed in the Oncology Service at Wills Eye Hospital from 1974 to 1987, 10 patients (0.39%) were black. Data on patient age (mean: 53.9 years), sex (male-to-female ratio: 7:3), and relative frequency of disease between black (0.39% of total cases) and white patients were similar to that of previous reports. The distinguishing characteristics (incidence, risk factors, complications, and prognostic indicators) of uveal melanoma in black versus white patients also were reviewed.  相似文献   
10.
Chromatographic separation of highly polar basic drugs with ideal ionspray mass spectrometry volatile mobile phases is a difficult challenge. A new quantification procedure was developed using hydrophilic interaction chromatography-mass spectrometry with turbo-ionspray ionization in the positive mode. After addition of deuterated internal standards and simple clean-up liquid extraction, the dried extracts were reconstituted in 500 microL pure acetonitrile and 5 microL was directly injected onto a Waters Atlantis HILIC 150- x 2.1-mm, 3-microm column. Chromatographic separations of cocaine, seven metabolites, and anhydroecgonine were obtained by linear gradient-elution with decreasing high concentrations of acetonitrile (80-56% in 18 min). This high proportion of organic solvent makes it easier to be coupled with MS. The eluent was buffered with 2 mM ammonium acetate at pH 4.5. Except for m-hydroxy-benzoylecgonine, the within-day and between-day precisions at 20, 100, and 500 ng/mL were below 7 and 19.1%, respectively. Accuracy was also below +/- 13.5% at all tested concentrations. The limit of quantification was 5 ng/mL (%Diff < 16.1, %RSD < 4.3) and the limit of detection below 0.5 ng/mL. This method was successfully applied to a fatal overdose. In Switzerland, cocaine abuse has dramatically increased in the last few years. A 45-year-old man, a known HIV-positive drug user, was found dead at home. According to relatives, cocaine was self-injected about 10 times during the evening before death. A low amount of cocaine (0.45 mg) was detected in the bloody fluid taken from a syringe discovered near the corpse. Besides injection marks, no significant lesions were detected during the forensic autopsy. Toxicological investigations showed high cocaine concentrations in all body fluids and tissues. The peripheral blood concentrations of cocaine, benzoylecgonine, and methylecgonine were 5.0, 10.4, and 4.1 mg/L, respectively. The brain concentrations of cocaine, benzoylecgonine, and methylecgonine were 21.2, 3.8, and 3.3 mg/kg, respectively. The highest concentrations of norcocaine (about 1 mg/L) were measured in bile and urine. Very high levels of cocaine were determined in hair (160 ng/mg), indicating chronic cocaine use. A low concentration of anhydroecgonine methylester was also found in urine (0.65 mg/L) suggesting recent cocaine inhalation. Therapeutic blood concentrations of fluoxetine (0.15 mg/L) and buprenorphine (0.1 microg/L) were also discovered. A relatively high concentration of Delta(9)-THC was measured both in peripheral blood (8.2 microg/L) and brain cortex (13.5 microg/kg), suggesting that the victim was under the influence of cannabis at the time of death. In addition, fluoxetine might have enhanced the toxic effects of cocaine because of its weak pro-arrhythmogenic properties. Likewise, combination of cannabinoids and cocaine might have increase detrimental cardiovascular effects. Altogether, these results indicate a lethal cocaine overdose with a minor contribution of fluoxetine and cannabinoids.  相似文献   
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