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991.
Orbital tuberculoma masquerading as an orbital malignancy   总被引:1,自引:0,他引:1  
Background: Orbital tuberculosis is exceedingly rare in areas where tuberculosis is non-endemic. A case of childhood orbital tuberculosis is reported, which the authors believe to be the first reported case of orbital tuberculosis in the Australasian region. Methods/Results: The patient, a 6-year-old boy, presented with proptosis and was initially mistaken to have an orbital malignancy. Treatment with antituberculous drugs resulted in resolution of the condition. Conclusion: This case served as a timely reminder of the need to keep awareness of the extrapulmonary manifestations of tuberculosis alive even in developed countries. A high index of suspicion for this eminently treatable disease in the appropriate clinical situation is particularly important when migrant communities from high-prevalence areas are involved.  相似文献   
992.
Leucocyte beta 1,3 galactosyltransferase activity in IgA nephropathy   总被引:8,自引:0,他引:8  
BACKGROUND: Reduced galactosylation of the O-linked glycans of the IgA1 hinge region in IgAN has recently been described. To investigate the underlying defect resulting in this abnormality, we have measured the activity of beta 1,3 galactosyltransferase, the enzyme responsible for galactosylation of O-linked sugars. METHODS: A galactose-acceptor substrate was prepared from degalactosylated hinge region fragments of normal IgA1, and incubated with the T cell, B cell, and monocyte lysates from patients with IgAN and controls for acceptor regalactosylation. The extent of acceptor galactosylation was then measured with biotinylated Vicia villosa lectin (VV), which is specific for ungalactosylated moieties. Lectin binding of serum IgA from the same subjects was also measured. RESULTS: T cell and monocyte beta 1,3 galactosyltransferase activities did not differ between IgAN and control, but B cell lysates in IgAN showed significantly lower beta 1,3 galactosyltransferase activity than control (6.2 +/- 0.71 vs. 9.5 +/- 1.03 AU/microgram, P = 0.018). Furthermore, B cell beta 1,3 galactosyltransferase activity showed a negative correlation (r = - 0.87, P = 0.002) with VV lectin binding of serum IgA in IgAN, but not controls. CONCLUSIONS: These data indicate that altered IgA1 O- galactosylation in IgAN results from a B cell-restricted reduction of beta 1,3 galactosyltransferase activity. This enzyme defect may be a fundamental pathogenic abnormality in IgAN.   相似文献   
993.
The diagnostic usefulness, limitations, and adverse reactions associated with computed tomographic myelography using metrizamide were assessed for broad outpatient application. The initial approach was to examine inpatients (n = 38) with low-dose metrizamide (100 mgI/ml). This low dose was believed less likely to be associated with side effects. They were then treated as if they were outpatients, with the liberties this entailed. The consequences of needle puncture were minimized by using a 25-gauge disposable needle. Thirty-four (89%) patients remained free of side effects after the procedure. Subsequently, this technique was extended to 42 outpatients, 38 (90.5%) of whom remained asymptomatic. For comparison, 170 mgI/ml was used in another 25 outpatients, who evidenced more symptoms. The potential medical, economic, and therapeutic benefits of obviating hospitalization by safer outpatient CT myelography seem clear.  相似文献   
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The objective of this study was to determine if assisted hatching improved the rates of implantation, clinical pregnancy and ongoing pregnancy for in-vitro fertilization (IVF) patients aged > or =36 years. On the day of oocyte aspiration, consenting patients were randomized according to whether all embryos underwent the hatching procedure (hatched; n = 41) or all embryos remained unhatched (controls; n = 48). Patients in both groups were treated with methylprednisolone and doxycycline starting on the day of oocyte retrieval and continuing for 4 days. The hatching procedure was performed approximately 55 h after insemination on all potential embryos for transfer and employed the release of acidified acid Tyrode's medium against the zona pellucida to create an opening approximately 20 microm in diameter. No significant differences were noted in the mean age, number of oocytes aspirated and number of embryos transferred between the hatched and control groups. In addition, no significant differences were observed in the rates of implantation (11.1 versus 11.3%), clinical pregnancy (39.0 versus 41.7%) and ongoing pregnancy (29.3 versus 35.4%) between the hatched and control groups respectively. These results suggest that assisted hatching may have no significant impact on IVF success rates in the patient population studied.   相似文献   
998.
Single-lung transplantation: imaging features   总被引:1,自引:0,他引:1  
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