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91.
PURPOSE: This study aimed to investigate the safety and efficacy of trabeculectomy with intraoperative mitomycin C (MMC) in the management of eyes with neovascular glaucoma (NVG). METHODS: Fifteen eyes of 14 patients with NVG were included in the study. NVG was secondary to central retinal vein occlusion (3 eyes), hemiretinal vein occlusion (2 eyes), proliferative diabetic retinopathy (8 eyes), branch retinal vein occlusion (1 eye) and idiopathic (1 eye). Preoperative retinal ablation was performed in eyes with evidence of posterior segment ischaemia. Following this, all eyes underwent trabeculectomy with intraoperative MMC (0.4 mg/ml for 3 minutes). Clinical outcome assessment included visual acuity, intraocular pressure (IOP), bleb appearance, identification of complications and antiglaucoma medications required to control IOP. RESULTS: The mean IOP decreased from 38.6 +/- 12.9 mmHg (range, 15-64 mmHg) to 17.4 +/- 9.33 mmHg (range, 4-34 mmHg) (P = 0.001). Preoperative visual acuity ranged from light perception to 6/9 in the affected eye. Thirteen (86.6%) of 15 eyes improved vision or retained preoperative vision, one (6.7%) eye lost light perception and one (6.7%) eye developed tractional retinal detachment two years after trabeculectomy. Ten (66.7%) of 15 eyes were classified as surgical success with a mean follow-up of 28.6 +/- 26.3 months (range, 2-82 months). None of the patients developed choroidal haemorrhage, hypotony maculopathy, late onset bleb leak or endophthalmitis. CONCLUSION: Trabeculectomy with intraoperative MMC is a good treatment modality in the management of eyes with NVG.  相似文献   
92.
Both cooked red meat intake and chronic inflammation/infection are thought to play a role in the etiology of colon cancer. The heterocyclic amine 2-amino-3-methylimidazo[4,5-f ]quinoline (IQ) is formed during cooking of red meat and may be involved in initiation of colon cancer. Reactive nitrogen oxygen species (RNOS), components of the inflammatory response, contribute to the deleterious effects attributed to inflammation on normal tissues. This study assessed the possible chemical transformation of IQ by RNOS. RNOS were generated by various conditions to react with (14)C-IQ, and samples were evaluated by HPLC. Myeloperoxidase (MPO)-catalyzed reaction was dependent upon both H(2)O(2) and NO(2)(-). This reaction produced an azo-IQ dimer and IQ dimer along with two nitrated IQ products identified by ESI/MS. 2-Nitro-IQ was not detected. Product formation was inhibited by 2 mM cyanide. Reduction in nitrated products observed with 100 mM chloride was not altered with 0.5 mM taurine. Nitrated products were also produced by other conditions, ONOO(-) and NO(2)(-) + HOCl, which generate nitrogen dioxide radical. In contrast, conditions which generate N(2)O(3), such as diethylamine NONOate, produced only small amounts of nitrated products with the major product identified by MS and NMR as N-nitroso-IQ. MPO activation of IQ to bind DNA was dependent upon both H(2)O(2) and NO(2)(-). RNOS generated by ONOO(-) and DEA NONOate also activated IQ DNA binding. The nitrated IQ products were not activated by MPO to bind DNA. In contrast, N-nitroso-IQ was activated to bind DNA by MPO +/- NO(2)(-). HOCl activated N-nitroso-IQ, but not IQ. RAW cells produced N-nitroso-IQ and increased amounts of NO(2)(-)/NO(3)(-), when incubated with 0.1 mM IQ and stimulated with lipopolysaccharide and interferon gamma. Results demonstrate chemical transformation and activation of IQ by RNOS and activation of its N-nitroso product by biological oxidants, events which may contribute to initiation of colon cancer.  相似文献   
93.
94.
This study addresses the utility of fine-needle aspiration (FNA) in assessing lymphadenopathy in patients with and without a previous history of malignancy. We reviewed the FNAs of superficial and deeply seated lymph nodes performed at our institution over a period of 18 yr (1983-2001). Where applicable, we also reviewed and report here the results of subsequent surgical excisional biopsies. We analyzed data from 439 patients, who ranged in age from 1 to 90 yr. The neck and retroperitoneum were the most frequently sampled sites (47% and 25%, respectively). Among the 439 FNAs, adequate material was obtained in 421 cases (96%); the remaining 18 were unsatisfactory (4.1%). Malignant diagnoses were rendered in 330 cases (75% of 439), four were suspicious for lymphoma (0.9%), and 87 were read as reactive lymph nodes or granulomas (20%). The most common malignant cytologic diagnoses from these lymph node FNAs were adenocarcinoma, squamous cell carcinoma, and lymphoma. We compared results between two major groups: patients with a history of malignancy and those without. FNA showed malignancy in 87% of patients with a history of cancer and 41% without such a history. Thirty-three or 10% of patients with a history of malignancy were given a benign diagnosis and follow-up surgical excisional biopsies were performed in nine of these cases. Four of the nine showed low-grade lymphoma. Of the 18 non-diagnostic FNAs, nine came from patients with a history of malignancy and in six of these nine who had a follow-up surgical excisional biopsy the lymph nodes were positive for malignancy. Of the other nine, who had no history of malignancy, only two had follow-up biopsies and both of these were negative. Patients with a history of malignancy are more than twice as likely to show malignancy on lymph node FNA compared to those without such a history (87% vs. 41%). Knowing whether a patient has a history of malignancy provides the appropriate level of suspicion for ordering ancillary investigations or even recommending excisional biopsy for further evaluation.  相似文献   
95.
Clearance of infectious organisms does not always require polarised Th1 or Th2 responses and it may be advantageous for both Th1 and Th2 responses to be elicited for effective protection against an invading pathogen. It was the aim of this study to investigate oxidised mannan as a possible Th1/Th2 adjuvant. Oxidised mannan was conjugated to two candidate antigens and delivered intranasally to mice. Immunisation with the oxidised conjugate resulted in significant antigen specific proliferative responses, IL-2, IFN-gamma and IL-4 production when compared to unconjugated controls.  相似文献   
96.
97.
The thymus is the major site of T cell maturation; extensive proliferation, differentiation, and apoptosis occur in this organ. During mammary tumorigenesis, there is a profound involution of the thymus associated with a severe depletion of the most abundant subset of thymocytes, CD4+8+ immature cells. Experiments to investigate the mechanism of loss of the CD4+8+ population indicated that there was no increase in the systemic levels of glucocorticoids, no loss of bone marrow precursors, and no decrease in precursor seeding of the thymus. Likewise, no enhanced emigration of thymocytes from the thymus to the periphery was observed in tumor-bearing mice. A slight increase in apoptosis was found in tumor bearers' thymi, but there was no apparent decrease in the proliferation of early thymic precursors CD48 cells. Importantly, severely altered levels of subpopulations of the CD48 precursors, consistent with an arrest in differentiation at an early stage of development, were detected. Moreover, thymic stromal cell function appeared to become impaired during tumorigenesis, possibly due to the action of tumor-derived factors. Thus, downregulation of cell-mediated immune functions occurring at late stages of the disease may be causally related to the thymic involution occurring during mammary tumorigenesis.  相似文献   
98.
Selenium levels in dilated cardiomyopathy   总被引:1,自引:0,他引:1  
Thirty-seven dilated cardiomyopathy cases have been studied and compared with 20 normal controls. Serum selenium levels in relation to coronary risk factors were studied. Serum samples were analysed for selenium, total cholesterol, high density lipoprotein(HDL) cholesterol, triglycerides and glucose levels. Smoking, alcohol intake, positive family history, psychosocial tension, obesity, hypercholesterolaemia, hypertriglyceridaemia and hyperglycaemia were found in the following percentages 27%, 8%, 5%, 73%, 41%, 38%, 81%, 46% respectively in dilated cardiomyopathy patients. Low selenium (< 4.5 micrograms/dl) and HDL cholesterol levels and high total cholesterol, triglycerides, low density lipoprotein cholesterol, very low density lipoprotein cholesterol and glucose levels were observed in dilated cardiomyopathy cases compared to controls. The present results support the concept that low selenium levels along with other risk factors play an important role in developing dilated cardiomyopathy.  相似文献   
99.
Thymomas are the most frequent primary tumors of the anterior mediastinum. These lesions are slow growing and can be locally invasive, but extrathoracic metastases are rare, occurring in less than 2% of cases. Fine-needle aspiration biopsy (FNAB) may be helpful in making the diagnosis of metastatic thymoma, with or without a clinical history of primary mediastinal thymoma. We report three cases of metastatic thymoma diagnosed by FNAB. Each case illustrates a distinctive cytologic pattern. While two of the patients had a history of histologically confirmed thymoma 11 and 13 years previously, a third patient presented with an enlarged supraclavicular lymph node and pulmonary nodules, and no prior diagnosis of thymoma. These cases demonstrate that based on distinctive cytologic patterns and features, a diagnosis of metastatic thymoma can be made with FNAB. Ancillary studies will often confirm the diagnosis. Diagn Cytopathol 1994;11:182–187. © 1994 Wiley-Liss, Inc.  相似文献   
100.
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