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61.
The results of conventional cerebrospinal fluid (CSF) investigations (CSF cell count, protein and glucose concentrations and Pandy's test for CSF globulin) obtained on admission and sequentially from weekly follow-up lumbar punctures for 4 weeks were evaluated in 99 children (median age 28 months) with stage II (50 children) and stage III (49 children) tuberculous meningitis. On admission, six children (6%) had a CSF cell count greater than 500 x 10(6)/l and nine (9%) a polymorphonuclear predominance. A CSF protein less than 0.8 g/l was found in 17 children (18%) of 97 in whom CSF protein was evaluated. Globulin was either absent or present as a trace only in 26 children (27%). CSF glucose was less than 2.2 mmol/l in 58 cases (60%) and less than 2.5 mmol/l in 67 (69%). In 63 children weekly CSF specimens obtained for the 1st 4 weeks of therapy showed an uninterrupted decline in cell count in 23 (37%), a fluctuating downward trend in 27 (43%) and a fluctuating upward trend in 13 (21%). Sequential CSF protein values in 57 children showed an uninterrupted rise in three (5%), a fluctuating upward course in 19 (33%), an uninterrupted downward trend in seven (12%), and a fluctuating downward course in 28 (49%). Of the 61 children in whom sequential CSF glucose concentrations were available, 11 (18%) experienced fluctuating concentrations, values falling to less than 2.2 mmol/l after being greater than 2.2 mmol/l on admission or after having risen to greater than 2.2 mmol/l.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The effect of keyhole data acquisition on quantitative analysis of dynamic MRI was examined. Experiments were performed retrospectively on raw data obtained from clinical dynamic contrast-enhanced breast imaging procedures. The effects of keyhole phase-encoding acquisition and type of reconstruction algorithm on the accuracy of derived quantitative parameters was assessed. Results indicate that the minimum keyhole size used should be restricted by the approximate minimum size of the expected lesions. Furthermore, reconstruction algorithms that offer improved image resolution do not circumvent this restriction.  相似文献   
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Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections.  相似文献   
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Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia.  相似文献   
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