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71.
近年来,超声定量检查技术在临床的应用为心血管疾病患者的心功能评估提供了量化的依据,本文介绍了超声诊断仪的使用部分最新定量检查技术。 相似文献
72.
Summary The sensitivity of the cochlea is dependent upon maintenance of a delicate homeostatic environment. One mechanism which participates in providing this environment is the autoregulation of cochlear blood flow. This autoregulation is ensured through the interaction of sympathetic, peptidergic and hemodynamic mechanisms. The current study demonstrates an adaptation that also participates in cochlear blood flow autoregulation. Specifically, an anterior inferior cerebellar arterial network is described and the relative contributions of each of its vessels to total cochlear blood flow is measured using laser Doppler flowmetry. The results show that each collateral vessel contributes to the blood supply of the cochlea and that reperfusion is accompanied by hyperemia. These findings suggest an adaptation that provides stable blood flow through redundancy and compensatory potential. Additionally, these observations have implications for experimental models of ischemia. 相似文献
73.
观察室性早搏43例,多普勒频谱表现为峰值流速减慢,早搏使前一组A峰消失,后一组峰值流速增快。19例早发型,主动脉瓣口、肺动脉瓣口无频谱出现,早搏每搏量因发生时间不同,每搏量减少不同,晚发型平均减少37.6%,早发型平均减少79.6%。讨论了产生机理及对心排量的影响。 相似文献
74.
Two-step endoscopic resection of gastric leiomyomas 总被引:2,自引:0,他引:2
Pasquale Spinelli Federico G. Cerrai Antonino R. Cambareri Emanuele Meroni Paolo Pizzetti 《Surgical endoscopy》1993,7(2):90-92
Summary Our two-step technique for endoscopic treatment of gastric leiomyomas is illustrated. From January 1979 to June 1991, nine symptomatic patients with sessile leiomyomas of the stomach were treated at the Endoscopy Division of Istituto Nazionale Tumori, Milan.The diagnosis was achieved by means of endoscopic observation of the lesion and, when possible, by ultrasound endoscopy.This new technique consists of first removing superficial portion of the tumor by electrosurgical snare. Second, a cleavage plane is found within the proper muscle layer; the tumor is enucleated as much as possible by tightening the snare around it and creating a pseudo-stalk. No major complication occurred nor were any recurrences observed at 21.8 months in the 7/9 patients treated by endoscopy alone. Endoscopic therapy was performed on an outpatient basis and only large lesions required short hospitalization. 相似文献
75.
经颅多普勒频谱参数与急性颅脑损伤患者颅内压的关系 总被引:2,自引:2,他引:0
目的探讨急性颅脑损伤患者的经颅多普勒频谱参数与颅内压的关系。方法应用TCD检测20例急性中、重型颅脑损伤患者双侧大脑中动脉,同时行颅内压监测。结果经颅多普勒频谱参数cf、PI、af、RI、ae均和ICP正相关,Vd、ac和ICP负相关,其中cf与ICP的相关系数最大。建立TCD相关参数与ICP的多元线性回归方程:ICP=0.312MAP-1.531Vd+21.437PI-15.059ac+38.722cf(P<0.001,R2=0.920估计值的标准差=4.0972mmHg)。结论经颅多谱勒频谱参数可以反应颅脑损伤患者的颅内压的改变。综合研究经颅多谱勒频谱参数、血压与颅内压的关系是应用经颅多普勒无创监测颅内压的方向。 相似文献
76.
目的 通过对24例阴道肿瘤患者的B超声像图分析,总结B超诊断阴道肿瘤的方法。方法 收集24例1995~2002年,我院门诊及住院患者的病史资料及声像图,结合病理结果分析声像图特征,并与病理加以对照。结果 24例患者声像图表现为囊性、实质性、囊实性肿瘤。结论 通过对声像图的分析,探讨了B超诊断阴道肿瘤的可行性、声像图特征及该方法的局限性。 相似文献
77.
Phonophoresis is defined as the migration of drug molecules, contained in a contact agent, through the skin under the influence of ultrasound. Several drugs have been introduced into the body by this technique. The design of a phonophoretic drug delivery system is in developmental stages in various research laboratories. Parameters affecting the delivery of drugs by this technique and devices available for drug delivery purposes are discussed in this review. 相似文献
78.
A significant increase of cutaneous laser Doppler flowmetry was found before blood flow decreases with increasing pressure during a 5 mmHg min−1 increase of pressure strain on the finger. Pre-treatment with a local anaesthetic or chronically applied capsaicin, resulted in the disappearance of the vasodilatory response. These results suggest an original vasodilatory axon reflex response to non-noxious pressure strain which is initiated by capsaicin-sensitive nerve terminals in the human skin. 相似文献
79.
David J. Murray Robert B. Forbes Judith B. Dillman Larry T. Mahoney David L. Dull 《Journal canadien d'anesthésie》1989,36(3):295-300
In this study, two-dimensional and pulsed Doppler echocardiography were used to measure cardiovascular changes before and
after IV atropine in 31 infants and small children during halothane (n = 15) or isoflurane (n = 16) anaesthesia. Prior to
induction of anaesthesia heart rate (HR), mean blood pressure (MBP), and two0dimensional echocardiographic dimensions of the
left ventricle and pulmonary artery bloodflow velocity were measured by pulsed Doppler echocardiography. Cardiovascular measurements
were repeated while anaesthesia was maintained at 1.5 MAC halothane (n = 15) or isoflurane (n = 16). Atropine 0.02 mg·kg−1 IV was then administered and two minutes later, a third set of cardiovascular data was obtained. Heart rate decreased during
halothane anaesthesia but did not change significantly during isoflurane anaesthesia. Mean blood pressure, cardiac output
(CO) and stroke volume (SV) decreased similarly during 1.5 MAC halothane or isoflurane anaesthesia. Ejection fraction (EF)
decreased and left ventricular end-diastolic volume (LVEDV) increased significantly in bothgroups, but decreases in EF (32
± 5 percentvs18 ± 5 per cent) and increases in LVEDV (18 ± 7 per cent vs7 ± 5 per cent) were significantly greater during
halothane than during isoflurane anaesthesia. Following atropine, HR increased more in the patients maintained with halothane
(31 ± 6 per cent), than during isoflurane anaesthesia (18 ± 5 per cent). Atropine increased CO in both groups of patients,
but SV and EF remained unchanged. When compared with awake values, HR increased similarly and significantly (18 ± 4 per cent)
following atropine in both groups, and CO returned to control levels. Halothane decreased EF and increased LVEDV more than
isoflurane at 1.5 MAC end— expired anaesthetic levels. Atropine did not diminish the myocardial depression produced by halothane
or isoflurane. The increase in CO following atropine during halothane and isoflurane anaesthesia in infants and small children
is the result of increases in HR alone.
Nous avons utilisé un appareil à échocardiographie bi-dimensionnelle couplé à un Doppler pulsé chez des bébés et de jeunes
enfants pour évaluer l’impact hémodynamique de l’halothane (n = 15) et de l’isoflurane (n = 16) et la modification possible
de ces effets par l’atropine. Nous avons mesure la frequence cardiaque (FC), la pression artérielle moyenne (PAM), la dimension
de la cavité ventriculaire gauche (par écho bi-dimensionnelle) et la vélocité du flot sanguin pulmonaire (par Doppler) et
ce, en trois occasions soit avant l’induction, après l’instauration de 1.5 MAC d’halothane ou d’isoflurane et finalement,
deux minutes après l’injection IV de 0.02 mg·kg−1 d’atropine. On ne nota une baisse de la frequence cardiaque qu’avec l’halothane tandis que la PAM, le débit cardiaque (DC)
et le volume d’éjection (VE) diminuaient autant avec l’un ou l’autre anesthésique. La diminution de la fraction d’éjection
(FE) et l’augmentation du volume télédiastolique du ventricule gauche (VTDVG) significatives pour les deux groupes, étaienl
plus marqué avec l’halothane qu’avec l’isoflurane: FE 32 ± 5 pour cent vs18 ±5 pour cent; VTDVG 18 ± 7 pour cent vs 7 ± 5
pour cent. Avec l’atropine, la FC monta plus dans le groupe halothane (31 ± 6 pour cent) que dans le groupe isoflurane (18
± 5 pour cent), le DC augmentant dans les deux groupes, alors que le VE et la FE demeuraient inchangés. Comparée aux mesures
pré-induction, l’atropine amenait une hausse significative de la FC, semblable dans les deux groupes (18 ± 4 pour cent) et
restaurait le DC. Donc, chez les bebes et les jeunes enfants, a 1.5 MAC, l’halothane diminue la FE et augmente le VTDVG plus
que ne le fait l’isoflurane. L’atropine ne modifie pas la depression myocardique et elle ne restaure le DC que par une hausse
de la FC.
Supported by PHS Grant No. 8507300 from the College of Medicine, University of Iowa Hospital, Iowa City, IA. 相似文献
Supported by PHS Grant No. 8507300 from the College of Medicine, University of Iowa Hospital, Iowa City, IA. 相似文献
80.
Guerriero S Ajossa S Lai MP Risalvato A Paoletti AM Melis GB 《Human reproduction update》1999,5(5):515-529
This review describes the usefulness of colour Doppler energy (CDE) (or power Doppler) imaging to measure vascularization in the female reproductive tract. CDE imaging is characterized by an increased sensitivity to flow, and thus may be useful in low-flow states and when optimal Doppler angles cannot be obtained. In addition, longer segments of vessels and more individual vessels can be visualized with CDE imaging. The role of CDE imaging in the evaluation of stromal vasculature in normal and in polycystic ovaries is described, and the relationship between follicular vascularity and outcome following in-vitro fertilization are discussed, together with the findings obtained from the evaluation of thecal arteriole of corpus luteum in early pregnancy. The fundamental role of CDE imaging in differentiation among ovarian masses is also reviewed. We summarize the role of CDE imaging in pregnancy, and describe two new applications of three-dimensional power Doppler sonography and the use of ultrasound contrast media. In conclusion, CDE imaging can replace conventional colour Doppler when the information on the direction of flow is not useful. Moreover, the technique appears superior to others for describing microvascular architecture and determining the presence or absence of flow. 相似文献