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71.
72.
Pornpatr Likittanasombut MD Patrick Reynolds MD Dana Meads RVT Charles Tegeler MD 《Journal of neuroimaging》2006,16(1):34-38
BACKGROUND: Common carotid artery (CCA) volume flow rate (VFR) is clinically useful for study of cerebrovascular disease. Color Velocity Imaging Quantification (CVI-Q; Philips Ultrasound International, Irvine, CA), previously reported as accurate and reliable, tracks the flow lumen over the cardiac cycle, as well as mean spatial velocity, which is multiplied by vessel area to obtain VFR. VFR can also be obtained by Doppler sampling for mean velocity, and vessel area based on static B-mode lumen diameter. We compared CCA VFR by CVI-Q and Doppler method (DM), since knowledge of how they compare is crucial when both are used clinically. METHOD: We prospectively studied patients having clinical carotid duplex exams and healthy controls. All had CCA VFR measured by both methods in the same exam session. RESULTS: Thirty-four studies were reviewed. CCA VFR by CVI-Q in those without ICA stenosis was 337 +/- 96 mL/m, and by DM 359 +/- 130 mL/m; P = .33. There was no difference between methods for 50-75% or 75-95% ICA stenosis. In 7 patients with ICA occlusion, and 3 with 95-99% stenosis, VFR was higher by DM than by CVI-Q (Occlusion: 125 vs 58 mL/m, P = .007; 95-99%: 152 vs 63 mL/m, P = .038). There was no statistically significant difference between methods for measurement of the ratio of VFR between right and left CCA. CONCLUSION: In patients with 0-95% ICA stenosis, VFR by CVI-Q and DM showed no difference. For 95-100% ICA stenosis the methods differ; with higher VFR by DM. Side-to-side VFR ratios remain constant, irrespective of VFR method, and can still provide clinically useful information. 相似文献
73.
单一的稳定剂并不能解决甘蓝复合果蔬汁的稳定性问题,而多种稳定剂的稳定效果较好,为此挑选出较好的3种稳定剂,对其进行不同比例的复配,观察一段时间的相对粘度及浊度变化,发现两种稳定剂的复配就能达到稳定的效果,最佳添加量(质量分数)为果胶0.07%,黄原胶0 03%. 相似文献
74.
The autonomic nervous control of cardiac function during active orthostatic load has been studied by measuring the power spectrum of heart rate fluctuations in 16 insulin-dependent diabetic patients and 14 age-matched control subjects. The patients were subdivided into two groups: 8 with normal respiratory sinus dysrhythmia (RSA+) and 8 with reduced respiratory sinus dysrhythmia (RSA-). In RSA- patients the total power (0.01-0.50 Hz) was significantly reduced compared with control subjects (4.7 versus 15.5 min-2, 2p less than 0.05) and the pattern of heart rate fluctuations was characterized by a relative increase in the low-frequency component (0.01-0.05 Hz) as compared with RSA+ patients and control subjects (45% versus 24% and 27%, both 2p less than 0.01). There was also a significant reduction in the high-frequency component (0.15-0.50 Hz) as compared with RSA+ patients and control subjects (17% versus 36% and 33%, both 2p less than 0.05). During standing, a significant increase in total power was found only in control subjects (2p less than 0.01) and the difference between control subjects, and RSA+ and RSA- patients reached significance (32.2 versus 15.1 and 12.7 min-2, 2p less than 0.02 and 2p less than 0.01). The pattern of heart rate fluctuations in RSA- patients showed no significant change on standing. These results suggest that the reduced overall heart rate variability in diabetic patients with cardiac autonomic neuropathy is associated with a typical heart rate fluctuation pattern. 相似文献
75.
报道72例急性心肌梗塞患者的心率变异性(HRV)值与心肌梗塞范围的关系,并与120例正常人的HRV值进行对比,结果发现,心肌梗塞急性期HRV值明显降低,与正常组对比有显著统计学意义,但HRV值降低与心肌梗塞部位、范围无关,可能主要为心肌梗塞引起的应激反应所造成的体液及神经调节改变所致。 相似文献
76.
Aichi Ogasawara Takahiro Hirano Hiroaki Hisa Susumu Satoh 《Clinical and experimental pharmacology & physiology》1995,22(4):311-313
1. Intrarenal arterial infusion of hypertonic saline (HS) transiently increased and then gradually reduced renal blood flow (RBF) in anaesthetized dogs. Glomerular filtration rate (GFR) but not filtration fraction decreased at the end of the infusion. 2. In the presence of a potassium channel opener cromakalim (0.3 μg/kg per min), HS infusion failed to reduce RBF; the initial increase in RBF was maintained throughout the infusion. Since cromakalim also prevented the decrease in GFR, HS infusion lowered filtration fraction. 3. The results suggest that cromakalim inhibits both pre-and postglomerular vasoconstriction induced by HS infusion. 相似文献
77.
60 intracranial tumors have been studied immunohistochemically to determine the proliferation rate by staining for the monoclonal antibody KI-67, which recognizes a nuclear antigen expressed by cells in proliferation. In gliomas a clear correlation of stained nuclei to the histologically determined degree of malignancy was found: slow growing astrocytomas and oligodendrogliomas had an average proliferation rate of 1%, more malignant forms of 7–10%. Glioblastomas were found to have a growth fraction of 15%. Metastases had an even higher rate of 20% proliferating cells. In meningiomas the proliferation rate was mainly about 1%, but in three cases it was between 5% and 7%. Whether this is indicative for a higher risk of tumor recurrence, remains to be correlated to the clinical course. Hemangiopericytomas had a proliferation rate of 9% and 16%, respectively, the latter recurring within four months. It may be concluded from the results of this study, that investigation of intracranial tumors with KI 67 may be of prognostic value and can possibly contribute to an individualized tumor therapy. 相似文献
78.
近些年来对A群多糖脑膜炎菌苗最适免疫剂量进行了一系列现场流行病学及血清学效果的对比研究。首先肯定了我国生产的菌苗与法国Merieux研究所生产的苗苗在人体接种后观察一年内具有同等杀菌抗体反应。以后在严格对比下观察了国内生产的多糖菌苗接种30μg及50μg一年内的血清杀菌抗体反应。结果完全相同;而全身反应则30μg为50μg剂量的五分之一。在我国80年代流脑流行地区内确证了30μg免后人群保护率为99%与国外50μg的保护率(97.2%)相似。国内连续三年在流行地区内对比观察了30μg、与50μg的流行病学预防效果,其人群保护率相似.与国外(Reingold).的报告亦相似。最后结论是本菌苗的最适免疫剂量为30μg.不但其预防效果与50μg相同,而且菌苗反应轻微,经济效益高,有利于在发展中国家推广使用。 相似文献
79.
江苏省婴儿死亡报告工作中,出现漏报率为17.87%,婴儿死亡漏报率为25.61%,农村出生漏报率和婴儿死亡漏报率均高于城市。婴儿死亡漏报中年龄越小,漏报越多;男女性别之间无显著性差异。城乡婴儿死亡漏报的主要死因是肺炎、意外死亡、新生儿窒息和先天畸形。本文还分析了造成漏报的主要原因,并提出了防止漏报的对策和干预措施。 相似文献
80.
不同培养基对肠球菌检出率的影响 总被引:3,自引:1,他引:2
用pH9.6葡萄糖肉汤、6.5%NaCl琼脂平板、3%—5%羊血琼脂平板三种不同培养基,从同一份样品中分离肠球菌,检出率有显著差别。pH9.6葡萄糖肉汤对检样选择性增菌后,再用6.5%NaCl琼脂平板分离肠球菌,其检出率明显高于现正普遍用于肠球菌初代分离的3%~5%血琼脂平板(P<0.05),也高于单纯使用6.5%NaCl琼脂平板(P<0.05);后两者间无显著差别(P>O.05)。属中种的构成在不同培养基上检出情况也不同。 关键词:培养基 肠球菌 检出率 肠球菌广泛存在于自然界,是水、空气、尘 相似文献