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31.
Hiroshi Ohuchi Masataka Hatanaka Keiko Abe Shogo Yatsu 《The Japanese Journal of Thoracic and Cardiovascular Surgery》2005,53(6):302-304
Off-pump surgery was performed in a patient with post-infarction angina complicated with aneurysmal coronary-pulmonary arterial fistula. Epicardial echocardiography localized the artery feeding the fistula in the myocardium, which had not been revealed by visual inspection, palpation, or transesophageal echocardiography. The patient underwent off-pump coronary artery bypass grafting concomitant with aneurysmectomy. The feeding arteries were dissected easily using a Harmonic Scalpel and ligated. The flow in the aneurysm disappeared immediately and aneurysmectomy was performed without bleeding. 相似文献
32.
脑干、三叉神经及大脑动脉环的可视化研究 总被引:2,自引:0,他引:2
目的 建立人体脑干、三叉神经及大脑动脉环的可视化数字模型。方法 采用首例中国数字化可视人体数据集,在SGI工作站上对脑干及其周围毗邻结构进行计算机三维重建并立体显示。结果 获得人体脑干、三叉神经及大脑动脉环等器官组织的三维重建结构,可对其进行任意径线和角度的适时三维测量。结论 首例中国数字化可视人体数据集能够提供完整而精确的解剖断面数据,脑干及其毗邻的三叉神经、大脑动脉环的可视化模型准确反映出该区域复杂的解剖学结构特点及其相邻器官间的空间毗邻关系,可为该区域的疾病的影像诊断和外科治疗提供形态学依据。 相似文献
33.
Roopa Thukaram William A Suarez Sreekanthan Sundararaghavan 《Catheterization and cardiovascular interventions》2005,66(1):18-20
A symptomatic 1,400 g premature triplet underwent successful transcatheter coil embolization of patent arterial duct using the umbilical artery. One 3 mm x 3 cm Flipper coil was used with no angiographic residual shunt. To the best of our knowledge, this is one of the smallest preterm infants to undergo this transcatheter procedure. 相似文献
34.
Normal cerebral perfusion measurements using arterial spin labeling: reproducibility, stability, and age and gender effects. 总被引:4,自引:0,他引:4
Laura M Parkes Waqar Rashid Declan T Chard Paul S Tofts 《Magnetic resonance in medicine》2004,51(4):736-743
Before meaningful conclusions can be drawn from clinical measures of cerebral blood perfusion, the precision of the measurement must be determined and set in the context of inter- and intrasubject sources of variability. This work establishes the reproducibility of perfusion measurements using the noninvasive MRI technique of continuous arterial spin labeling (CASL). Perfusion was measured in 34 healthy normal subjects. Intersubject variability was assessed, and age and gender contributions were estimated. Intersubject variation was found to be large, with up to 100% perfusion difference for subjects of the same age and gender. Repeated measurements in one subject showed that perfusion remains remarkably stable in the short term when compared with intersubject variation and the large capacity for perfusion change in the brain. A significant decrease in the ratio of gray-matter to white-matter perfusion was found with increasing age (0.79% per year (P < 0.0005)). This appears to be due mainly to a reduction in gray-matter perfusion, which was found to decrease by 0.45% per year (P = 0.04). Regional analysis suggested that the gray-matter age-related changes were predominantly localized in the frontal cortex. Whole-brain perfusion was 13% higher (P = 0.02) in females compared to males. 相似文献
35.
Luis Hernandez-Garcia Gregory R Lee Alberto L Vazquez Chun-Yu Yip Douglas C Noll 《Magnetic resonance in medicine》2005,54(4):955-964
A new approach to modeling the signal observed in arterial spin labeling (ASL) experiments during changing perfusion conditions is presented in this article. The new model uses numerical methods to extend first-order kinetic principles to include the changes in arrival time of the arterial tag that occur during neuronal activation. Estimation of the perfusion function from the ASL signal using this model is also demonstrated. The estimation algorithm uses a roughness penalty as well as prior information. The approach is demonstrated in numerical simulations and human experiments. The approach presented here is particularly suitable for fast ASL acquisition schemes, such as turbo continuous ASL (Turbo-CASL), which allows subtraction pairs to be acquired in less than 3 s but is sensitive to arrival time changes. This modeling approach can also be extended to other acquisition schemes. 相似文献
36.
目的探讨肾动脉狭窄介入治疗前后血清脑利钠肽BNP水平的变化及意义。方法采用回顾性调查方法,对肾动脉狭窄介入治疗前后血清脑利钠肽水平的变化进行分析。结果肾动脉狭窄介入治疗再通后,血清BNP水平出现下降(P〈0.01)。结论血清BNP水平的变化对肾动脉狭窄介入治疗后疗效的评价具有一定的临床指导意义。 相似文献
37.
在53只乌拉坦麻醉家兔身上,观察到延髓孤束核(NTS)区注射γ-氨基丁酸(GABA)使血压显著下降,安定(DZ)有相似的降压效应,荷包牡丹碱(BIC)和印防己毒素(PIC)则使血压升高;促甲状腺素释放激素(TRH)和甲硫脑啡肽(MTP)对血压无明显影响;延髓的另一些区域应用GABA等药物后血压变化不明显;提示GABA能神经递质系统参与心血管活动的抑制性中枢调节,NTS区是其作用部位之一。 相似文献
38.
39.
Seiji Yano Shoichiro Sumi Yoshinori Nio Tatsuro Ooishi Yasunari Kawabata Yoshimitsu Minari Katsuhiro Tamura 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(3):340-345
A case of insulinoma is reported in a patient in whom selective arterial calcium injection (SACI) tests were performed both
to confirm tumor localization before surgery and to confirm complete tumor removal during surgery. An 18-year-old woman with
hypoglycemic episodes was diagnosed with an insulinoma in the pancreatic body demonstrated by celiac arteriography. In a preoperative
SACI test, calcium was injected into the splenic artery (SpA), gastroduodenal artery (GDA), and superior mesenteric artery
(SMA). Serum immunoreactive insulin (IRI) and proinsulin levels were measured in hepatic venous samples. IRI was markedly
increased after the injection of calcium into the GDA and SMA, while there was no response in IRI levels when calcium was
injected into the SpA. Therefore, no occult insulinoma was revealed in the distal area fed by the SpA, although the presence
of insulinoma was uncertain in the proximal pancreas. In the intraoperative SACI test, calcium was injected into the celiac
artery. Insulin (determined by enzyme immunoassay) and proinsulin levels were measured in portal venous samples before and
after resection of the tumor. After resection, these levels decreased in response to the calcium stimuli, confirming complete
removal of the insulinoma. The SACI test was helpful to localize the insulinoma and was useful to confirm the complete removal
of the tumor. 相似文献
40.
Dr Andrzej Sapinski MD 《Journal of clinical monitoring and computing》1994,10(6):373-376
Objective. The objective of this study was to compare blood pressure (BP) measured by the sphygmooscillographic method with that measured by the direct and auscultatory methods.Methods. In 15 adult patients undergoing cardiac surgery, blood pressure was measured by the sphygmooscillographic and direct methods simultaneously on the same upper extremity. In another group of 86 children and 11 adults, blood pressure was measured by the sphygmooscillographic and auscultatory methods simultaneously, with one cuff. For the sphygmooscillographic measurement, we used sphygmomanometer-S, which measures blood pressure on the basis of the amplitude height (oscillometric) and the morphology (sphygmographic) of pulse waves recorded by a transducer placed in the cuff.Results. The systolic and diastolic blood pressure measured by the sphygmooscillographic method were both 2 mm Hg higher than those from the direct method; the mean blood pressure was 0.6 mm Hg higher. These differences were not significant. Compared with the auscultatory method, sphygmooscillographic systolic values were higher by 7 mm Hg, while diastolic values were lower by 9 mm Hg. These differences were significant.Conclusions. Blood pressure measurements obtained by the sphygmooscillographic method correlate well with the direct method for measuring blood pressure in children and adults; but, they do not correlate well with the auscultatory method. 相似文献