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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
146.
Angiogenesis and Brain Oedema in Intracranial Meningiomas: Influence of Vascular Endothelial Growth Factor 总被引:12,自引:0,他引:12
M. Bitzer H. Opitz J. Popp M. Morgalla A. Gruber E. Heiss K. Voigt 《Acta neurochirurgica》1998,140(4):333-340
Summary The correlation between angiographic neovascularization, peritumoural brain oedema (PTBOe) and the expression of vascular
endothelial growth factor (VEGF) , was analysed in 30 patients with intracranial meningiomas.
Pre-operative angiograms were examined for the existence of either an exclusively dural tumour blush or an additionally pial
tumour supply from cerebral arteries. Furthermore the presence of macroscopic tumour-neovascularization and dysplastic changes
of tumour-draining cerebral veins was evaluated. VEGF expression was investigated on histological tissue samples, using immunohistochemical
techniques. VEGF immunohistochemistry and neuroradiological evaluations were performed in double blind fashion. Tumour volume
and the amount of oedema were calculated by computerized tomography (CT) or magnetic resonance imaging (MRI). The oedema-tumour
volume ratio was defined as oedema index (OeI).
Compared to VEGF-negative meningiomas, tumours with striking VEGF staining revealed a significant higher mean oedema index
(OeI=4,2 vs. OeI=1,5; p<0.018), and a higher oedema incidence (91,7% vs. 44,4%; p<0.046). Equally, meningiomas with additionally
tumour supply from cerebral arteries were associated with a significant higher mean OeI (OeI=4.1 vs. OeI=1.2; p<0.01) and
oedema incidence (94,7% vs. 20,0%; p<0,0023) than meningiomas with exclusively tumour supply from dural arteries. All meningiomas
with striking VEGF-expression were associated with vascular tumour supply from cerebral arteries, but VEGF-negative tumours
only in 50% (p<0.029). These data suggest a link between VEGF-expression, arterial tumour supply and peritumoural brain oedema.
The development of tumour supply from cerebral arteries may be important for formation of meningioma-related oedema. Therefore,
VEGF may represent a potent mediator in the evolution of this type of vascularization in meningiomas. 相似文献
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An account is given of possible approaches and means available today to cope with physical and medicamentous prophylaxis of thrombosis in gynecologico-obstetric practice. Literature is evaluated, and preference is given to methods which have been safely established by verifiable diagnostic techniques as being applicable to prophylaxis of thrombosis. Due consideration is given to individual inclinations to thrombosis and haemorrhage. Therefore, emphasis is laid on low doses of heparin or dextran. 相似文献
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