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81.
PURPOSE: To describe a case of severe dry eye syndrome in a child. METHODS: Observational case report. The authors describe a 10-year-old male with severe dry eyes who was profoundly disabled by pain and photophobia despite aggressive conventional therapy. Lacrimal gland histology was consistent with the primary Sj?gren syndrome, and serologic and immunohistologic evidence supported the hypothesis of Epstein-Barr virus causality. RESULTS: Treatment with systemic acyclovir and cyclosporin A resulted in dramatic and rapid reversal of the profound sicca syndrome and enabled the patient to resume his normal activities. CONCLUSION: Epstein-Barr virus dacryoadenitis should be considered in the differential diagnosis of keratoconjunctivitis sicca in children. Epstein-Barr virus can cause keratoconjunctivitis sicca, which can be treated successfully with acyclovir therapy in addition to suppression of the inflammatory response.  相似文献   
82.
PURPOSE: To describe a case of chronic cicatrizing conjunctivitis in a patient with ocular cicatricial pemphigoid and Wegener granulomatosis. METHODS: Observational case report. A retrospective study. RESULTS: An 80-year-old man presented with chronic cicatrizing conjunctivitis, peripheral corneal thinning, and Wegener granulomatosis, which were diagnosed by his referring physician based on clinical (recurrent epistaxis, sinus congestion) and histopathologic features of nasal mucosa (granulomatous inflammation, vasculitis). A conjunctival biopsy performed by us disclosed features of active Wegener granulomatosis and ocular cicatricial pemphigoid, which indicate lack of control of both diseases with methotrexate treatment. The patient died of pulmonary complications from Wegener granulomatosis 1 week after our evaluation. CONCLUSION: Ocular cicatricial pemphigoid and Wegener granulomatosis are both potentially fatal autoimmune diseases. Ocular involvement in Wegener granulomatosis indicates poor control of the underlying systemic condition and is a marker for active vasculitis, which indicates the need for treatment with cyclophosphamide.  相似文献   
83.
84.
Treatment of mouse L929 cells with immune T (type II) interferon resulted in the induction of two double-stranded (ds) RNA-dependent enzymes which have been described previously in viral (type I) interferon-treated cells: pppA(2′p5′A)n synthetase and protein kinase(s). The induction of these enzymes by T interferon was blocked by anti-T but not by antiviral interferon serum. The kinetics of the development of the antiviral state along with a comparison of the levels of pppA(2′p5′A)n synthetase and protein kinase in T and viral interferon-treated cells were investigated. In addition, [35S]methionine-labeled extracts from control, T, and viral inteferon-treated cells were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and two-dimensional gel electrophoresis. Extracts from cells treated with either type of interferon were found to contain several identical proteins, of estimated molecular weights 60,000, 88,000, and 120,000, which were absent or found at much lower levels in preparations from control cells. The newly synthesized proteins can be partially purified by chromatography on columns of poly(I)·poly(C)-Sepharose, thus providing a convenient method for their further characterization. These results show that treatment of cells with T interferon results in the induction of intracellular events identical to those observed in viral interferon-treated cells.  相似文献   
85.
BACKGROUND: Patients with end-stage renal disease (ESRD) require dialysis to maintain survival. The optimal timing of dialysis initiation in terms of cost-effectiveness has not been established. METHODS: We developed a simulation model of individuals progressing towards ESRD and requiring dialysis. It can be used to analyze dialysis strategies and scenarios. It was embedded in an optimization frame worked to derive improved strategies. RESULTS: Actual (historical) and simulated survival curves and hospitalization rates were virtually indistinguishable. The model overestimated transplantation costs (10%) but it was related to confounding by Medicare coverage. To assess the model's robustness, we examined several dialysis strategies while input parameters were perturbed. Under all 38 scenarios, relative rankings remained unchanged. An improved policy for a hypothetical patient was derived using an optimization algorithm. CONCLUSION: The model produces reliable results and is robust. It enables the cost-effectiveness analysis of dialysis strategies.  相似文献   
86.
We demonstrate the presence of high affinity receptors specific for interferon-gamma (IFN-gamma) in human lymphoblastoid Namalva cells. The presence of these receptors, whose binding affinity and cross-linking characteristics were not distinguishable from those of the corresponding receptors in sensitive cells, was not consistent with the lack of responsiveness of Namalva cells to IFN-gamma as regards growth inhibition, induction of 2'-5' oligoadenylate synthetase activity and inhibition of virus multiplication. Nevertheless, IFN-gamma enhanced the expression of two genes, HLA class II and c-myc. Although the mechanism of these IFN-gamma-mediated modifications is not understood, these results provide evidence that the IFN-gamma receptors present in Namalva cells are functional.  相似文献   
87.
An international collaborative health screening project was undertaken to stimulate interest in child health education, to study feasibility of health screening in young children from diverse cultures, and to compare the distribution of chronic disease risk factors among 15 countries. Data for the 13-year-old participants showed that risk factors defined by cholesterol greater than 180 mg/dl, systolic blood pressure greater than 130 mm Hg, and daily or occasional smoking were present, to varying degrees, in children from each country. We found no relationship between obesity and cholesterol or blood pressure for these children. The acceptability of the screening, the children's enjoyment in participation, and the prevalence of risk factors at this young age lead to the conclusion that school-based health education programs should be initiated during childhood.  相似文献   
88.
The consumption of seafood within two to three days of testing can increase total urine arsenic concentrations. Few clinicians are familiar with this fact and often misinterpret elevated results. A retrospective chart review of all cases with arsenic testing seen between 1991 and 2004 at an occupational and environmental medicine referral clinic was performed. Urine arsenic results were classified as follows: total arsenic levels; speciated results (inorganic, ionic arsenic); and whether the patient abstained from seafood prior to the collection. Laboratory detection limits for total and for ionic arsenic were < or = 2 microg/L. Fifty-four patients with urine arsenic testing were identified. The total urine arsenic concentration exceeded 40 microg/L for 28 patients. On paired, speciated testing (n = 21), mean total arsenic was 122 +/- 227 microg/L, and ionic arsenic was not detected in any of these same samples (p = 0.023). On paired testing, before and after seafood abstention (n = 12), total urine arsenic without abstention was 291 +/- 267 microg/L, and it was only 9 +/- 12 microg/L after seafood abstention (p = 0.004). The total urine arsenic elevations observed in our series were due to benign organic arsenic compounds commonly found in seafood. Laboratories should reflexively perform speciation on most samples with elevated total arsenic concentrations prior to reporting the results. Reflexive speciation could reduce unnecessary referrals, further testing, and patient anxiety.  相似文献   
89.
Yu EN  Jurkunas U  Rubin PA  Baltatzis S  Foster CS 《Cornea》2006,25(5):621-622
PURPOSE: To report histopathologic findings and treatment of obliterative microangiopathy in a patient with chronic conjunctivitis due to relapsing polychondritis (RP). METHODS: This interventional case report describes a 50-year-old woman with relapsing polychondritis was referred to the Ocular Immunology and Uveitis Service for bilateral tearing due to refractory chronic conjunctivitis. Ocular examination revealed the presence of bilateral follicular conjunctivitis. Conjunctival biopsy of the inferior palpebral conjunctiva was performed, and the histopathologic findings guided the therapeutic intervention. RESULTS: The pathology of the conjunctival biopsy included granulomatous obliterative microangiopathy with numerous eosinophils, plasma cells, lymphocytes, and epithelioid cells in the substantia propia. The chronic conjunctivitis resolved with systemic methotrexate therapy. CONCLUSIONS: Microangiopathy may cause chronic conjunctivitis in patients with RP and may be a harbinger of evolving nonocular problems as a consequence of incomplete control of this autoimmune disorder. Immunomodulatory therapy should be considered in such cases to prevent possible cardiovascular, renal, respiratory, and neurologic complications of vasculitis. Although methotrexate has been used in treatment of RP-related necrotizing scleritis with poor results, it can be sufficient for the conjunctivitis with microangiopathy associated with RP.  相似文献   
90.
Purpose: Urgency and urge incontinence are frequently observed after prostatectomy. Although symptoms ameliorate within a relatively short time, they usually cause significant stress and anxiety to the patient as far as their duration is concerned. Aim of our study was to determine the efficacy of tolterodine in preventing urgency and urge incontinence after catheter removal in patients that underwent prostatectomy for benign prostate hyperplasia. Patients and methods: Twenty-seven patients with moderate/severe lower urinary tract symptoms due to benign prostatic enlargement, scheduled for prostatectomy, were randomised into two groups, Group A (14 pts) received tolterodine 2 mg b.i.d starting the day of surgery, while group B patients received no such treatment. Tolterodine treatment was discontinued 15 days after catheter removal. All patients completed the International Prostatic Symptom Score (IPSS) and the International Continence Society (ICS-BPH) forms the day before surgery, and three times more, one, fifteen and thirty days after catheter removal. Results: Pre-operative total 1PSS and frequency of urgency/urge incontinence as determined by questions 3 and 4 of the ICS-BPH questionnaire were equally distributed between groups. Tolterodine was well tolerated and no adverse effects were reported. Post-operative IPSS and QoL scores did not differ between groups. However, the frequency of urge incontinence both the first day and fifteen days after catheter removal was significantly lower in the tolterodine group (16.6% vs. 69.2%, p=0.004 and 8.3% vs. 38.4%, p=0.039, respectively). Conclusion: Tolterodine was well tolerated in all patients and had a beneficial effect regarding the postoperative urge incontinence. Trials of a larger scale could determine which patients would benefit more, especially according to the presence of storage lower urinary tract symptoms prior to surgery.  相似文献   
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