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81.
82.
Primary central nervous system (CNS) lymphoma is a non-Hodgkin's lymphoma restricted to the nervous system. The incidence of this lymphoma is rising in the immunocompetent population but may be decreasing in patients with the acquired immune deficiency syndrome (AIDS) due to the introduction of highly active antiretroviral therapy. A periventricular, diffusely enhancing lesion on magnetic resonance imaging (MRI) is suggestive of primary CNS lymphoma, but a stereotactic biopsy is needed to make a definitive diagnosis. Concurrent leptomeningeal and ocular involvement is common in this brain tumor. Because primary CNS lymphoma is exquisitely sensitive to steroids, these drugs should be withheld until tissue is obtained for diagnosis. Age and performance status are important prognostic factors, regardless of specific treatment. Methotrexate in high doses is the single most effective chemotherapeutic agent for primary CNS lymphoma. It substantially improves survival when combined with radiation therapy and is better than radiotherapy alone as a single agent. Multimodality treatment results in delayed cognitive neurotoxicity, particularly in older patients. New treatment protocols have focused on the use of chemotherapy alone. 相似文献
83.
Pedersen LM Terslev L SŁrensen PG Stokholm KH 《Medical oncology (Northwood, London, England)》2000,17(2):117-122
Transcapillary escape rate of albumin was determined in 22 patients with different malignancies. In addition, urinary albumin
excretion rate was measured in 24-h urine samples using a sensitive immunoassay. Increased urinary albumin excretion was defined
as ≥20 μg/min according to conventional standards. Renal glomerular filtration and tubular function was estimated by51Cr-EDTA plasma clearance and urinary beta 2-microglobulin, respectively. Median urinary albumin excretion rate was 15.0 μg/min
(range 6–510 μg/min) and the frequency of increased urinary albumin excretion was 41%. This agrees with other studies showing
increased albuminuria in several types of malignant diseases. Patients with advanced disease (tumour, node, metastasis (TNM)
stage II–IV) had a significantly higher urinary albumin excretion rate than patients with localized disease (TNM stage I).
Serum creatinine, glomerular filtration rate and urinary beta 2-microglobulin were all within normal limits. Median transcapillary
escape rate of albumin was 5.5%/h (range 2–8%/h) and this level is comparable with values in healthy subjects. There was no
significant difference in transcapillary escape rate between patients with elevated urinary albumin excretion and the normoalbuminuric
group. Median value of the absolut outflux of albumin was 10.6 g/h with similar levels in patients with increased urinary
albumin excretion and patients with normoalbuminuria. Our results indicate a high prevalence of minor glomerular dysfunction
with a slightly elevated urinary albumin excretion in patients with malignancies. The normal endothelial function, as estimated
by the transcapillary escape rate of albumin, suggests an overal unaffected capillary permeability and increased urinary albumin
loss appears to be an isolated renal phenomenon in cancer patients. 相似文献
84.
85.
Objective : To describe the obstetric and perinatal factors, in particular the method of delivery, associated with development of a subgaleal haematoma (SGH) and to determine the outcome of survivors with this type of birth trauma. Methodology : Perinatal and obstetric data were retrospectively reviewed for 37 infants admitted to the neonatal unit of the sole tertiary paediatric referral hospital in Western Australia with an SGH, over a 24 year period from 1970 to 1993. These data were compared to data for all Western Australian births. The long-term outcome was obtained through medical and private paediatric records for 26 of these infants. Results : All except one of the neonates had instrumental deliveries; 89% had a vacuum extractor applied to the head at some stage of delivery compared to 10% of the general population of births in Western Australia. There was also a significantly increased risk of failure of attempted vacuum extraction. Of the cases where a vacuum extraction was attempted, 45% also had forceps applied to the head. Coagulopathy was associated with the severity of the SGH. There was also a high frequency of occurrence (40%) of associated head trauma such as intracranial haemorrhage, skull fracture and cerebral oedema, as well as neonatal encephalopathy (73%). The occurrence of these associated features did not correlate significantly with the severity of SGH. Minor complications of SGH included jaundice and facial bruising. There was an excess mortality associated with SGH; however, the long-term outcome for neonatal survivors with this disorder was good. None of the cases studied subsequently developed cerebral palsy or intellectual disability, and minor neurological sequelae only were documented in four infants. Conclusions : SGH is an uncommon type of birth trauma, and is associated with delivery or attempted delivery by vacuum extraction. The most commonly associated clinical problems were hypovolaemia and coagulopathy. The long-term outcome for neonates with this condition is good. 相似文献
86.
Prevalence of deep venous thrombosis in the lower extremities of children in the intensive care unit
Gia A. DeAngelis Joan McIlhenny Douglas F. Willson Sarah Vittone Samuel J. Dwyer III James C. Gibson Bennett A. Alford 《Pediatric radiology》1996,26(11):821-824
Purpose. To determine the prevalence of lower extremity deep venous thrombosis (LE-DVT) in children who spent at least 72 h in the pediatric intensive care unit (ICU).
Materials and methods. Children up to the age of 17 years who spent at least 72 h in the ICU underwent lower extremity venous ultrasound at the end of their stay. Prevalence range for the sample size was calculated with a confidence interval of 95%.
Results. Among 76 children who spent 3–141 days in the ICU, the prevalence of acute (and silent) DVT was 4 % (confidence interval 0–9 %). All three affected children had femoral venous catheters in that leg during their ICU stay (17 unaffected children also had catheters).
Conclusion. Children in an ICU setting are at significantly lower risk for thrombosis than adults in the same setting. 相似文献
87.
Guanabenz, [(2,6-dichlorobenzylidene)amino]guanidine, acetate was shown to be the E-isomer. It decomposed to form the Z-isomer, 2,6-dichlorobenzaldehyde, aminoguanidine, and 2,6-dichlorobenzaldehyde semicarbazone. A stability-indicating assay for the intact drug in the presence of all of its decomposition products by the use of UV spectroscopy is presented. 相似文献
88.
89.
Brem SS Bierman PJ Black P Blumenthal DT Brem H Chamberlain MC Chiocca EA DeAngelis LM Fenstermaker RA Fine HA Friedman A Glass J Grossman SA Heimberger AB Junck L Levin V Loeffler JJ Maor MH Narayana A Newton HB Olivi A Portnow J Prados M Raizer JJ Rosenfeld SS Shrieve DC Sills AK Spence AM Vrionis FD;National Comprehensive Cancer Network 《Journal of the National Comprehensive Cancer Network : JNCCN》2005,3(5):644-690
90.