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71.
脑血流和灌注储备能力评价在有症状颅内动脉狭窄诊治中的价值 总被引:1,自引:0,他引:1
在有症状颅内动脉狭窄患者的脑血流和灌注储备能力尚未明确之前,仅根据患者的临床症状和动脉狭窄程度进行手术干预具有相当的盲目性。脑血流和灌注是评价是否存在脑缺血的最直接证据。由于侧支循环和脑血管本身储备能力,颅内血管狭窄和(或)血流速度下降等并不一定表明该血管供血区脑灌注下降。文章阐述了脑血流和灌注储备能力评价在有症状颅内动脉狭窄患者诊治中的价值。 相似文献
72.
Jamieson M. Bourque Eric J. Velazquez Robert H. Tuttle Linda K. Shaw Christopher M. O’Connor Salvador Borges-Neto 《Journal of nuclear cardiology》2007,14(2):165-173
Background Left ventricular ejection fraction (LVEF) is a significant predictor of morbidity and death. The nuclear summed rest score
(SRS) measures myocardial perfusion defects and provides prognostic information, but its effects on long-term outcomes are
not fully established. Moreover, information regarding the potential interaction between these 2 covariates is limited. The
purpose of this study was to determine whether the mortality risk associated with LVEF is the same across all values of SRS
in a population undergoing evaluation for ischemic heart disease.
Methods and Results We examined 3,187 patients who underwent cardiac catheterization and perfusion single photon emission computed tomography
imaging with a maximum follow-up of 8.1 years and median follow-up of 3.1 years. Cox proportional hazards modeling showed
that increasing nuclear SRS and decreasing LVEF were independently associated with a higher long-term mortality rate, with
a clinically significant interaction between them (P=.032). Patients with a normal LVEF and a high SRS (greater perfusion abnormality) have a prognosis similar to those with
a reduced LVEF.
Conclusions Resting perfusion studies provide prognostic information for long-term survival and significantly impact the interpretition
of mortality risk associated with changes in LVEF. Patient prognostication, risk stratification, and future research using
these variables should take this interaction into account.
Supported by a grant from the Tom & Lynn Royster Foundation. Durham, NC, and a National Institutes of Health Research Fellowship
Grant (T5 GM08679-04), Bethesda, Md. 相似文献
73.
74.
William E. Gillies FRACS FRACO FRCS Anne MV Brooks MD PhD FRACS FRACO FRACP 《Clinical & experimental ophthalmology》1996,24(3):169-187
Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process. 相似文献
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process. 相似文献
75.
介绍一种用单片机构成的自动灌流控制系统。它以灌流压为控制指标,以LDB-M电子蠕动泵作为执行机构,构成闭环控制系统,能实现用户设定的各种液流压曲线。系统内采用了EEPROM存储器,可对用户设定的多达10条灌流曲线进行长期保存。 相似文献
76.
目的:探讨体外循环(cardiopulmonarybypass,CPB)术中采用低温洗涤红细胞肺保护液实施肺动脉灌注对肺的保护效果。方法:随机选取20例风湿性单纯二尖瓣病变合并中度肺动脉高压的患者,分为肺动脉灌注组和对照组(每组各10例)。灌注组在主动脉阻断后,经肺动脉根部间断灌注低温洗涤红细胞肺保护液,测定两组患者围术期的机械通气时间、肺血管阻力、白细胞比值(静脉血/动脉血)、肺循环血浆MDA含量。结果:体外循环术后灌注组机械通气时间显著低于对照组(P<0.05);各时点肺血管阻力、白细胞比值(静脉血/动脉血)、肺循环血浆MDA含量均显著低于对照组(P<0.01)。结论:低温洗涤红细胞肺保护液肺动脉灌注对体外循环术后肺损伤有明显的保护作用. 相似文献
77.
78.
The sodium intake of sodium deplete sheep was studied during local, push-pull perfusion of different solutions within the third cerebral ventricle. Sheep were made sodium deplete by continuous loss of parotid saliva, and were allowed access to 0.6 M NaHCO3 solution for 2 h daily. Local perfusion within the third cerebral ventricle was performed before and during the access to sodium solution. Four perfusion sites were used: anterior dorsal and ventral, and posterior dorsal and ventral. Perfusion of 200 mM Na-csf caused a decrease in sodium intake at each perfusion site. Perfusion of ouabain, 10−6M, caused a reduction in sodium intake only during perfusions within the anterior portion of the third ventricle. The results may indicate that specific neuronal elements sensitive to changes in intracellular sodium concentrations are located around the anterior portion of the third cerebral ventricle. These neurones, however, are not exclusive sites from where sodium intake of sodium deplete sheep can be influenced. 相似文献
79.
Toshifumi Murashita Keishu Yasuda Yoshiro Matsui Norihiko Shiiya Shigeyuki Sasaki Makoto Sakuma 《Surgery today》1997,27(4):368-372
A successful replacement of the aorta from the ascending aorta to the supraceliac abdominal aorta in one operation is herein reported. The patient was 66-year-old woman who had DeBakey type I chronic aortic dissection with a pre-disseminated intravascular coagulation (DIC) condition. The image diagnosis revealed a markedly enlarged false lumen with a narrow true lumen in the ascending aorta extending to the diaphragm level while below the diaphragm level, the aortic dilatation was mild. The operation was performed through both a thoracoabdominal incision and a median sternotomy to expose the whole thoracic aorta, and the aorta was replaced from the ascending aorta to the supraceliac abdominal aorta. Selective cerebral perfusion was used for cerebral protection and this was a useful adjunct since no time limitations were thus required during repair of the aortic arch. Although the patient developed several complications postoperatively, she eventually recovered and was discharged from the hospital without any neurological disorders. 相似文献
80.
在体肺隔离高温灌注的实验研究 总被引:1,自引:0,他引:1
8条犬于左肺动脉及左房分别插入灌注管及引流管后阻断,使左肺隔离。肝素化预充液中加入超量阿霉素进行常温及高温(41~43℃)的灌注转流。监测肺水含量、肺顺应性、血气、肺动脉压、肺实质温度、鼻咽温、血液学等指标,并行病理检查。结果表明:单侧肺隔离高温灌注在手术方法与转流技术上是可行的;它提供的热源简便,温度理想。高温灌注化疗对肺组织有一定影响,但其程度可逆;临床应用是可行的。 相似文献