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41.
PURPOSE: To study the clinical spectrum and treatment outcome of retinoblastoma in Indian children. PATIENTS AND METHODS: This retrospective study analyzed 488 eyes of 355 retinoblastoma patients treated at a tertiary care ophthalmic hospital in southern India during a 14-year period. RESULTS: Retinoblastoma involved one eye in 177 (50%) and both eyes in 178 (50%) patients. Mean age at presentation was 23.98 +/- 23.37.  相似文献   
42.
Surgical repair of double aortic arch: 16-year experience   总被引:1,自引:0,他引:1  
Double aortic arch (DAA) is a complete form of vascular ring causing tracheoesophageal compression. We analyzed long-term results of a series of DAAs, over a period of 16 years. Between 1987 and 2003, 29 children underwent surgery for airway and/or esophageal compression secondary to a DAA. Dominant symptoms were stridor, dysphagia, choking episodes, and life-threatening apneic spells (n = 7). Diagnosis was established by barium studies, bronchoscopy, echocardiogram, angiogram, computed tomography (CT), and magnetic resonance imaging (MRI). Seven patients had concurrent cardiac anomalies. Two children had an associated tracheoesophageal fistula. Surgery was accomplished by left thoracotomy (n = 25), right thoracotomy (n = 2) or median sternotomy (n = 2). The operative mortality was zero. There was one late death due to respiratory failure. Four (13.8%) patients had a surgical complication (chylothorax, 3 cases; acute renal failure, 1 case). Follow-up (mean 7.1 years; range 6 months to 16 years) was complete in all patients, and showed complete improvement in 22 patients and partial improvement in 6 patients. Early surgical repair of DAA is associated with low mortality, and results in marked symptomatic relief in most patients. Patients with tracheomalacia or associated asthma, constitute a high-risk group and may manifest persistent symptoms and require adjunctive procedures.  相似文献   
43.
Nm23 expression in retinoblastoma   总被引:1,自引:0,他引:1  
PURPOSE: Nm23 is a metastasis-suppressor protein. Decreased nm23 protein contributes to aggressiveness in many tumors. Nm23 immunoreactivity was studied in retinoblastoma and correlated with differentiation and invasiveness. METHODS: Immunohistochemistry was performed on 73 formalin-fixed, paraffin-embedded specimens of retinoblastoma. Western blot was conducted to confirm the immunohistochemical study. Prognostic features such as differentiation, invasion of choroid, optic nerve, and orbit, and metastasis were analyzed. RESULTS: Intense nm23 immunoreactivity was seen in 61% of the retinoblastomas with no invasion and faint nm23 immunoreactivity was seen in 85% of the retinoblastomas with invasion (p < 0.001). Poorly differentiated retinoblastoma showed decreased nm23 immunoreactivity compared to well-differentiated retinoblastomas (p = 0.02). An inverse correlation was observed between invasion of choroid, optic nerve, orbit, and metastasis, and nm23 immunoreactivity. Western blot assays of fresh tumor extracts confirmed the immunohistochemical findings. CONCLUSIONS: Decreased nm23 immunoreactivity was seen in poorly differentiated retinoblastomas and in retinoblastomas with invasiveness. These findings may lay the groundwork for further studies to better understand the molecular mechanisms and provide a more accurate prediction of invasion and metastasis of retinoblastoma.  相似文献   
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45.
Choroidal neovascular membrane, a known complication of choroidal osteoma causing visual loss when located subfoveally, can be successfully treated with transpupillary thermo therapy.  相似文献   
46.
It is possible that tuberculosis is transmitted from patients to healthcare workers (HCWs). However, there are few data on this from developing countries. The object of this study was to document the incidence of tuberculosis among HCWs in the Christian Medical College (CMC), Vellore, India during a 10-year period (January 1992-December 2001). Data were collected from records maintained in the staff and students health services of CMC. A total of 125 cases were diagnosed during the period of study. The overall incidence of sputum positive cases was similar to that observed in the general population, during most years. However, it appears that focal outbreaks occur with transmission between HCWs. The chance of developing extra-pulmonary tuberculosis was higher in HCWs compared with the general population.  相似文献   
47.
PURPOSE: To study the histopathologic features of 232 enucleated eyes with retinoblastoma. MATERIALS AND METHODS: Two hundred thirty-two enucleated eyes with retinoblastoma in a tertiary-care institute from 1982 to 2001 were reviewed. Data were collected and analyzed about the type of growth and the presence or absence of vitreous or subretinal seeding, rosettes and fleurettes, necrosis, calcification, iris neovascularization, and invasion of the anterior chamber, iris, choroid, optic nerve, and sclera. Choroidal invasion was graded using a new system. Results were analyzed for statistical significance. RESULTS: The endophytic growth pattern was common in 118 (51%) of the eyes. Vitreous seeds were present in 109 (47%) of the tumors, 23 (10%) of the tumors had subretinal seeds, and 14 (6%) of the tumors had both. Poorly differentiated tumors were present in 134 (58%) of the eyes. Iris neovascularization was noted in 71 (31%) of the eyes and choroidal invasion was observed in 78 (34%) of the eyes. Of these 78 eyes, full-thickness (stage 4) choroidal invasion was present in 51 (65%). Optic nerve invasion was observed in 75 (32%) of the eyes, of which prelaminar involvement occurred in 40 (53%) and postlaminar involvement occurred in 22 (29%). CONCLUSION: A higher incidence of choroidal and optic nerve infiltration was noted among Asian Indian children than among children from the West. This could be due to delayed diagnosis or to a difference in the biological behavior of tumors occurring in the Asian Indian population.  相似文献   
48.
OBJECTIVE: The objective of the present study is to evaluate and compare the infrared spectral features of normal and malignant exfoliated cervical cells, cells from malignant tissue, and the SiSo cell line. METHODS: Infrared spectra of cervical adenocarcinoma (CA) tissue, normal and malignant exfoliated cervical cells, and a uterine cervical adenocarcinoma cell line (SiSo) were obtained. Spectral qualities in terms of band intensity ratio and band position, which reflect configurational changes in the functional groups of the above samples, were measured. RESULTS: Spectral bands of CA tissue, exfoliated cells from CA, and the cell line were similar but markedly different from that of exfoliated normal cervical cells. Significant changes in bands at 1025 cm(-1) (glycogen), 1080 cm(-1) (glycogen and nucleic acids), 1155 cm(-1) (C-OH groups of serine, threonine, and tyrosine of cell proteins, and C-O groups of carbohydrates), 1240 cm(-1) (PO(2) groups of nucleic acids), 1400 cm(-1) (methyl group of lipids and proteins), and 1450 cm(-1) (methylene group of lipids and proteins) were noted in the CA tissue, exfoliated CA cells, and adenocarcinoma cell line compared with exfoliated normal cells. Marked shifts in band positions from 1080 to 1086 cm(-1), 1153 to 1160 cm(-1), and 935 to 970 cm(-1) in CA tissue, exfoliated CA cells, and the adenocarcinoma cell line were noted. CONCLUSION: Spectral bands of the adenocarcinoma cell line matched very well with those of cervical CA tissue and exfoliated CA cells in terms of position. In contrast, spectral bands of the SiSo cell line differed greatly from those of normal exfoliated cells.  相似文献   
49.
PURPOSE: To report the clinical characteristics of, discuss the surgical options for, and analyze the factors affecting the anatomic and visual outcome of intraocular cysticercosis. DESIGN: Retrospective, noncomparative, interventional case series. PARTICIPANTS: Forty-five eyes of 44 Indian patients with posterior segment intraocular cysticercosis. METHODS: The charts of 45 eyes, in which intraocular cysticercosis was removed by vitreoretinal surgery (either transscleral or transvitreal), were reviewed. MAIN OUTCOME MEASURES: These included the postoperative retinal status and the best-corrected Snellen visual acuity. RESULTS: Intraocular cysticercosis was present in the vitreous cavity of 27 eyes (60%) and in the subretinal space of 18 eyes (40%). Anterior segment inflammation was seen in 13 eyes (28.8%) and vitreous inflammation in 38 eyes (84.4%). Retinal detachment was observed in 22 eyes (48.8%), with proliferative vitreoretinopathy in 13 eyes (59.09%). Subretinal cysts anterior to the equator (4 eyes) were removed transsclerally, whereas subretinal cysts posterior to the equator and intravitreal cysts (41 eyes) were removed transvitreally. The mean follow-up was 10.5 months. At the last follow-up, the retina was attached in 39 eyes (86.6%); visual acuity of >/=5/200 was achieved in 67.5%. CONCLUSIONS: Current vitreoretinal surgical techniques enable removal of intraocular cysticercosis in all cases, with reattachment of the retina in 86.6% and recovery of ambulatory vision in approximately 67% of cases.  相似文献   
50.
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