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J. Mäurer A. Kendzia H. Gerlach D. Pappert J. Hierholzer K. J. Falke R. Felix 《Intensive care medicine》1998,24(11):1152-1156
Objective: To determine whether the quality of infiltrations in chest radiographs can accurately predict the histological extent of
fibrotic change in patients with acute respiratory distress syndrome (ARDS). Design: Retrospective clinical investigation. Setting: Intensive care unit (ICU) of a university teaching hospital. Patients and methods: Of 47 patients treated with extracorporeal membrane oxygenation (ECMO) for severe ARDS over a 5-year period, 23 patients
underwent open lung biopsy at thoracotomy for treatment, mostly of pneumothorax. Chest films obtained by portable chest roentgenography
preceding the operation were reviewed retrospectively and compared to the histomorphological results of the lung specimen.
Results: Chest radiographs displayed mixed alveolar-reticular opacification in 60.2 %, alveolar patterns in 22.9 % and reticular
opacities in 10.5 %. In 0.4 % there were no infiltrates, 6 % could not be evaluated because of insufficient quality. There
was no relevant difference between the right and left lungs. Subdividing patients into two groups according to the histological
results of either absent or mild (1) or severe (2) lung fibrosis, we found an alveolar haziness in 12.3 % in group 1 compared
with 28.2 % in group 2, while reticular characteristics were identified in 13 % and 11 %, respectively. Conclusions: The most common opacity in chest radiographs of patients with severe ARDS treated with ECMO is mixed alveolar-reticular
opacification. Severe lung fibrosis is not positively correlated with a reticular radiographic pattern. ECMO does not lead
to specific radiological changes in conventional radiograms, contrary to clinical findings that treatment with ECMO might
induce pleural or pulmonic haemorrhage, especially in the earlier days when systemic heparinization had to be used instead
of the heparin-coated tube-surfacing.
Received: 24 November 1997 Accepted: 20 July 1998 相似文献
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To evaluate the effect of interleukin-8 (IL8) on glomerular basement membrane (GBM) sulfated compounds and albuminuria, we
infused IL8 in 1% bovine serum albumin (BSA) for 5 days into the left renal artery of Holtzman male rats at the rate of 10
μl/h using an osmotic pump. Control rats received 1% BSA. A significant increase in urinary albumin/creatinine ratio was seen
on the last day of IL8 infusion (0.38±0.11, mean ± SEM) when compared with albumin/creatinine ratio prior to infusion (0.19±0.04,
P = 0.04). No significant differences in urinary albumin excretion prior to and after infusion of 1% BSA were observed. On
the last day of infusion, rats were injected with 35sulfate (1.0 mCi/200 g body weight) intraperitoneally and killed after 8 h. Glomeruli were isolated and GBM obtained. After
5 days of IL8 administration, there was a significant increase in 35sulfate uptake by GBM of the infused kidney (76±10 cpm/dry glomerular weight, mean ± SEM) compared with the uptake seen in
the contralateral kidney (53±9, P = 0.05). The in vivo infusion of IL8 increased the 35sulfate uptake by GBM and augmented the urinary albumin/creatinine ratio, suggesting that IL8 may induce albuminuria by altering
the metabolism of the GBM sulfated compounds. This hypothesis needs to be confirmed by studies on glomerular charge selectivity
and GBM anionic sites during the course of the infusion. Moreover, the persistence of the effect needs to be evaluated by
prolonging the infusion for more than 5 days.
Received June 3, 1996; received in revised form and accepted October 18, 1996 相似文献
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The voltage-gated currents of the astrocytes associated with the retinal capillaries of the rabbit retina were studied using whole-cell patch clamp recording. The resting potential of these cells was −70 ± 4.8 mV (mean ± SEM; n = 54), and the input resistance and cell capacitance were 558 ± 3.6 MΩ and 19.5 ± 1.8 pF respectively. Depolarization to potentials positive to −50 mV evoked rapidly activating inward and outward currents. The inward current was transient, eliminated by substitution of choline for Na+ in the bathing solution, and reduced by 50% in the presence of 1 μM tetrodotoxin. The time-to-peak of the Na+ current was more than twice that for the Na+ current found in retinal neurons. The glial Na+ current was half-inactivated at −55 mV. A transient component of the outward K+ current was blocked by external 4-aminopyridine while a more sustained component was blocked by external tetraethylammonium. At potentials between −150 and −50 mV the membrane behaved Ohmically. Voltage-gated currents in retinal astrocytes recorded in situ appear qualitatively similar to those described for some glial cells in vitro. 相似文献
78.
Summary. Platelet membranes provide procoagulant surfaces for the assembly and expression of the factor X-activating complex and promote the proteolytic activation and assembly of the prothrombinase complex resulting in normal hemostasis. Recent studies from our laboratory and others indicate that platelets possess specific, high-affinity, saturable, receptors for factors XI, XIa, IX, IXa, X, VIII, VIIIa, V, Va and Xa, prothrombin, and thrombin. Studies described in this review support the hypothesis that the factor X-activating complex on the platelet surface consists of three receptors (for the enzyme, factor IXa; the substrate, factor X; and the cofactor, factor VIIIa), the colocalization of which results in a 24 million-fold acceleration of the rate of factor X activation. Whether the procoagulant surface of platelets is defined exclusively by procoagulant phospholipids, or whether specific protein receptors exist for the coagulant factors and proteases, is currently unresolved. The interaction between coagulation proteins and platelets is critical to the maintenance of normal hemostasis and is pathogenetically important in human disease. 相似文献
79.
红细胞膜通道力学效应的探讨 总被引:1,自引:0,他引:1
萧天庆 《中国生物医学工程学报》1992,11(3):150-156
在考察红细胞双凹碟形体形成的基础上,讨论了红细胞的输氧功能与红细胞变形的关系,揭示了红细胞膜通道的力学效应:当红细胞呈双凹碟形时,PiPo的地方,红细胞膜通道有释放出氧的现象,其氧的总流率为 J=Lo_2(Pio_2-Poo_2) Lp(Pi-Po) 式中Lo_2为O_2分压差引起的膜通道对氧的流导,PiO_2、Poo_2为膜内外的氧分压;Lp为由于压差引起的膜通道对氧的流导。 相似文献
80.