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11.
Minbo Lan Nelson Beghein Nicolas Charlier Bernard Gallez 《Magnetic resonance in medicine》2004,51(6):1272-1278
New electron paramagnetic resonance (EPR) oximetry probes were identified in the class of carbon black materials. These compounds exhibit very high oxygen sensitivity and favorable EPR characteristics for biological applications. At low pO(2), the linewidth is particularly sensitive to changes in oxygen tension (sensitivity of 750 mG/mmHg). The application of the probes for oximetry was demonstrated in vivo: the pO(2) was measured in muscle in which the blood flow was temporarily restricted as well as in tumor-bearing mice during a carbogen breathing challenge. The responsiveness to pO(2) was stable in muscle for at least 3 months. No toxicity was observed using these materials in cellular experiments and in histological studies performed 2, 7, and 28 days after implantation. In view of their EPR characteristics (high sensitivity) as well as the well-characterized production procedure that make them available on a large scale, these probes can be considered as very promising tools for future developments in EPR oximetry. 相似文献
12.
高压氧对冠心病患者C-反应蛋白的影响 总被引:4,自引:4,他引:0
目的 了解高压氧(HBO)治疗对冠心病患者C 反应蛋白 (CRP)的影响。方法 冠心病患者共 60例,随机分为HBO治疗组(HBO组)30例和对照组 30例。HBO治疗压力 0. 2MPa,每日 1次,每周 6次,共治疗 4周。比较治疗前后两组CRP的测定结果。结果 HBO组治疗后CRP与治疗前差异有显著性意义(P<0. 001);治疗后两组CRP差异有显著性意义(P<0. 001);治疗前两组CRP差异无显著性意义(P>0. 05);对照组治疗前后CRP差异无显著性意义 (P>0. 05)。结论 HBO治疗可显著降低冠心病患者的CRP含量。 相似文献
13.
体外膜肺联合血液滤过治疗肺肾衰竭的实验研究 总被引:8,自引:0,他引:8
目的 观察体外膜氧合器(ECMO)联合高容量血液滤过(HVHF)对急性呼吸窘迫综合征(ARDS)、急性肾功能衰竭(ARF)的治疗作用。 方法 采用实验犬32只,随机分为A、B、C、D 4组。静脉注射油酸复制ARDS模型及双侧输尿管结扎复制急性肾功能衰竭模型。A组用ARDS呼吸机治疗;B组ARDS用ECMO治疗;C组ARDS+ARF用HVHF治疗;D组ARDS+ARF用ECMO联合HVHF治疗。监测血气、血流动力学以及血生化等指标。 结果 治疗后B组氧分压(PaO2)逐步上升,在治疗4 h后高于A组[(95.58±8.14) 比(82.79±12.37) mm Hg,P < 0.05]; C组PaO2治疗中较成模时无明显改善;D组PaO2呈逐渐上升趋势,在各时间点均高于C组(P < 0.05)。各组血流动力学指标在治疗中保持稳定。C、D组HVHF治疗后Scr、BUN明显降低[C组:Scr (320.89±65.42) 比(655.04±181.22) μmol/L,BUN (20.42±6.65) 比(41.53±10.59)mmol/L;D组:Scr (334.15±45.97)比(697.48±101.66) μmol/L,BUN (19.12±6.39) 比(39.10±11.60) mmol/L,P均< 0.01]。 结论 ECMO可以有效地改善ARDS低氧血症,联合HVHF可以提供肺肾功能联合支持。 相似文献
14.
Severe hemorrhagic radiation proctitis advancing to gradual cessation with hyperbaric oxygen 总被引:3,自引:0,他引:3
Dr. Jacky Charneau MD Gilles Bouachour MD Bruno Person MD Pascal Burtin MD Jean Ronceray MD Jean Boyer MD 《Digestive diseases and sciences》1991,36(3):373-375
Summary We report a case of a male patient suffering from a severe hemorrhagic radiation proctitis which gradually ceased with hyperbaric oxygen. We discuss the mechanisms of chronic radiation injury and the effect of the hyperbaric oxygen. This therapy is proposed as an alternative to surgical intervention for this abnormality. 相似文献
15.
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
16.
17.
紫外线照射充氧自血回输疗法治疗多形性红斑临床及甲皱微循环观察 总被引:2,自引:0,他引:2
采用紫外线充氧自血回输治疗多形性红斑的治疗组总有效率为100%,对照组为40%;甲皱微循环改善率治疗组为100%,对照组为75%,组间差异均有非常显著性(P<0.01).观察证明,紫外线照射充氧自血回输疗法是治疗多形性红斑的一种好方法. 相似文献
18.
高压氧对精索静脉曲张家兔附睾组织学影响的实验研究 总被引:1,自引:0,他引:1
目的研究高压氧(HBO)对精索静脉曲张(VC)家兔附睾组织学的影响,探讨精索静脉曲张导致男性不育的发病机制。方法采用HBO干预精索静脉曲张家兔模型,对睾丸、附睾的重量,附睾不同节段精子活力,附睾的组织形态以及精液参数进行研究。结果与未行HBO干预的VC模型比较,HBO 干预后的VC模型精液质量明显改善,睾丸、附睾重量明显增加(P值均<0.01),左侧附睾尾部Ⅱ级以上精子明显增加(Ⅱ级57.43%±6.48%,Ⅲ级2.91%±1.51%)(P<0.01,<0.05)。附睾上皮结构改善,腔内精子密度增加。结论 VC可导致附睾病理损害、精子成熟和获能障碍。慢性缺血、缺氧及其微循环障碍是导致附睾病理损害、精子成熟和获能障碍的主要机制。HBO可有效抑制VC致附睾的病理损害进程。 相似文献
19.
肝移植术后肝动脉血栓形成的治疗方法探讨 总被引:1,自引:0,他引:1
目的探讨肝移植术后肝动脉血栓形成的治疗方法。方法回顾性分析我院自2001年11月至2005年1月收治肝移植术后肝动脉血栓形成患者14例,分别采用动脉溶栓、血管支架植入、高压氧治疗及再次肝移植治疗。结果动脉溶栓11例,成功率45.5%(5/11),2例随访12个月肝功能正常,另3例均于随访期死亡,其中2例因吻合口狭窄曾行血管支架植入术。高压氧治疗3例,随访7个月,临床效果较好。急诊再次肝移植2例,术后均死于多器官功能衰竭。结论肝移植术后肝动脉血栓形成,动脉溶栓及血管支架植入治疗存在局限性,高压氧治疗效果良好,可与其他保守治疗联合使用,应避免急诊再次肝移植。 相似文献
20.
An Intrapleural Lung Prosthesis: Rationale, Design, and Testing 总被引:1,自引:0,他引:1
FRANCO L. FAZZALARI ROBERT H. BARTLETT MARK R. BONNELL J. PATRICK MONTOYA 《Artificial organs》1994,18(11):801-805
Abstract: Extracorporeal life support (ECLS or ECMO) is standard treatment for severe respiratory failure but poses many contraindications to future lung transplantation. The solution to this dilemma is the implantable gas exchange device (IGED) or artificial lung. Preliminary efforts to create such an artificial lung have been made since 1970 and include designs involving single devices, intravascular devices (i. e., IVOX), and combination heart–lung devices, Stringent requirements govern the design of such a device, the most important of which are high gas exchange efficiency, low resistance to blood flow, and size. This paper describes such a device. It incorporates large diameter inflow and outflow ports in close proximity and a low resistance wound hollow fiber core encapsulated in a compliant outer shell which conserves the work of the right ventricle. In a large animal model (adult sheep) this device was connected in line with the main pulmonary artery in series with the native lungs. This configuration has the advantages of using the lungs as an embolic filter, perfusing the lungs with fully oxygenated blood, and maintaining the integrity of the anatomy necessary for transplant. Laboratory experiments have run >8 h. Preliminary data show that the animals have remained hemodynamically stable while the devices have supported the animals completely by supplying 100% O2 saturation with PO2 values ranging from 250–350 mm Hg. Additionally, this model makes possible the study of respiratory failure without introducing other variables such as extracorporeal circuits or pumps. The other metabolic, endocrine, and reticuloendothelial functions of normal and injured lungs can now be studied more precisely by excluding these variables. Further studies are needed to evaluate this device in chronic (long–term implantation) experiments before clinical application. 相似文献