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101.
P. Knaapen S. de Haan O. S. Hoekstra R. Halbmeijer Y. E. Appelman J. G. J. Groothuis E. F. Comans M. R. Meijerink A. A. Lammertsma M. Lubberink M. J. W. Götte A. C. van Rossum 《Netherlands heart journal》2010,18(2):90-98
Hybrid imaging of positron emission tomography (PET) together with computed tomography (CT) is rapidly emerging. In cardiology, this new advanced hybrid imaging modality allows quantification of cardiac perfusion in combination with assessment of coronary anatomy within a single scanning session of less than 45 minutes. The near-simultaneous anatomical evaluation of coronary arteries using CT and corresponding functional status using PET provides a wealth of complementary information in patients who are being evaluated for (suspected) coronary artery disease, and could help guide clinical patient management in a novel manner. Clinical experience gained with this recently introduced advanced hybrid imaging tool, however, is still limited and its implementation into daily clinical practice remains largely unchartered territory. This review discusses principles of perfusion PET, its diagnostic accuracy, and potential clinical applications of cardiac PET-CT in patients with ischaemic heart disease. (Neth Heart J 2010;18:90–8.) 相似文献
102.
目的:观察凝血酶调节蛋白(Thrombomodulin,TM)基因转染兔髂动脉损伤模型后,对动脉血管内膜增生狭窄的防治作用。方法:用注射式加压转染的方式对兔动脉壁转染pcDNA3.1/hTM质粒,再制造动脉损伤-阻滞模型,于术后3天、7天、14天、28天用免疫组化的方法观察TM蛋白在各组血管腔内的表达,术后14天、28天用彩色多普勒观察活体吻合口内径和血流流速;再做病理切片Verhoeff染色,观察血管内膜增生的程度、部位,计算血管内膜面积、中膜面积和血管狭窄率。结果:术后3天、7天、14天、28天hTM质粒转染组中hTM表达一直保持在高水平,7天达到高峰,14天、28天虽有所下降但是表达强度仍然高于载体质粒转染组合空白对照组。在术后14天、28天彩色多普勒观察测量吻合口内径:hTM质粒转染组分别为1.93mm±0.34mm,1.89mm±0.28mm;载体质粒转染组为1.59mm±0.43mm,1.38mm±0.28mm;空白对照组1.46mm±0.25mm,1.44mm±0.32mm。在这两个时间点,hTM质粒转染组血管狭窄率为32±23%,37±14%;载体质粒转染组为58±21%,63±17%;空白对照组为58±19%,61±23%。结论:hTM基因在转染动脉壁后能减少动脉损伤-阻滞模型在后期的血管内膜增生,改善血管的狭窄状况。 相似文献
103.
《Reproductive biology》2020,20(2):202-209
The present detailed study aimed to establish for the first time the ovarian and uterine hemodynamic change in dairy cows after the end of the puerperal period to investigate a possible association between Doppler indices and volume of blood flow. Twenty cows weighing 500–600 kg (mean 400 ± 50 kg) and 4–5 years of age (mean 3.2 ± 0.5 years) categorized into two main groups (true anestrum, with corpus luteum, n = 10) and (normal cyclic, n = 10), The period of examination started from day 39 till day 70 after calving with day after day routinely examination by b-mode and Doppler performed on both ovaries with ovarian arteries (OA) and uterus with uterine arteries (MUA) in the ipsilateral (ipsi) and contralateral (contra) side to ovulation, in addition to a thickness in horns and body was measured. Estradiol and progesterone were also measured. Results showed that both Doppler indices in the OA and MUA ipsi and contra had a positive (P ≤ 0.001) correlation with contra Doppler indices, but revealed a negative (P ≤ 0.05) correlation with ipsi and contra Doppler velocities, blood flow rate and volume in anestrum cows. Both ovarian and uterine ipsi indices showed an increase (P ≤ 0.05) in the anestrum cows, and both PSV and EDV of both arteries ipsilateral showed (P ≤ 0.05) a decrease in the anestrum cows, the ipsi and contra ovarian and uterine colored % were lower in anestrum group than the normal group. Estradiol (P ≤ 0.05) decreased in anestrum cows than the normal, while progesterone increased in the anestrum group. Conclusion, although uterine and ovarian morphology were changed in anestrum cows, the vascular system of the ovary as well as uterus underwent much more marked vascular changes, the most significant being that of blood flow velocities and volume. 相似文献
104.
M. Masuda T. Emoto A. Suzuki M. Akutagawa T. Kitawaki K. Kitaoka H. Tanaka S. Obara K. Yoshizaki S. Konaka Y. Kinouchi 《Biomedical signal processing and control》2013,8(6):509-519
Arteriosclerosis is considered to be a major cause of cardiovascular diseases, which account for approximately 30% of the causes of death in the world. We have recently demonstrated a strong correlation between arteriosclerosis (arterial elasticity) and two characteristics: maximum systolic velocity (S1) and systolic second peak velocity (S2) of the common carotid artery flow velocity waveform (CCFVW). The CCFVW can be measured by using a small portable measuring device. However, there is currently no theoretical evidence supporting the causes of the relation between CCFVW and arterial elasticity, or the origin of the CCFVW characteristics. In this study, the arterial blood flow was simulated using a one-dimensional systemic arterial segments model of human artery in order to conduct a qualitative evaluation of the relationship between arterial elasticity and the characteristics of CCFVW. The simulation was carried out based on the discretized segments with the physical properties of a viscoelastic tube (the cross-sectional area at the proximal and terminal ends, the length, and the compliance per unit area of the tube (CS)). The findings obtained through this study revealed that the simulated CCFVW had shape similar characteristics to that of the measured CCFVW. Moreover, when the compliance CS of the model was decreased, the first peak of the simulated-CCFVW decreased and the second peak increased. Further, by separating the anterograde pulse wave and the reflected pulse wave, which form the CCFVW, we found that the decrease in the first peak of the simulated CCFVW was due to the arrival of a reflected pulse wave from the head after the common carotid artery toward the arrival of a anterograde pulse wave ejected directly from the heart and that the increase in the second peak resulted from the arrival of the peak of the reflected pulse wave from the thoracic aorta. These results establish that the CCFVW characteristics contribute to the assessment of arterial elasticity. 相似文献
105.
目的:观察PerClot^TM多聚糖止血颗粒在兔股动脉局部止血效果。方法:分离并剪断兔股动脉,应用多聚糖止血颗粒止血,通过测定出血量与止血时间同阴性对照组对比了解活动患肢对止血稳定性的影响。结果:受试2组平均出血量如下:PerClot^TM组:(1.46±0.06)g;阴性对照组(2.48>±0.10)g。统计分析后可知PerClot^TM组较阴性对照组出血量减少(P〈0.叭。平均止血时间如下:PerClot^TM组:(100±30.1)s;阴性对照组(200±36.33)g。统计分析后可知PerClot^TM组较阴性对照组止血时间减少(P〈0.01).活动患肢对止血稳定性无影响。结论:多聚糖颗粒止血效果可靠,有临床应用前景,值得进行临床实验。 相似文献
106.
Anne Holt Müller Gro Klitgaard Povlsen Claus Heiner Bang-Berthelsen Lars Schack Kruse Janne Nielsen Karin Warfvinge Lars Edvinsson 《BMC genomics》2015,16(1)
Background
microRNAs (miRNAs) are important regulators of translation and have been implicated in the pathogenesis of a number of cardiovascular diseases, including stroke, and suggested as possible prognostic biomarkers. Our aim was to identify miRNAs that are differentially regulated in cerebral arteries after subarachnoid hemorrhage (SAH), using a rat injection model of SAH and a qPCR-based screen of 728 rat miRNAs. Additionally, serum was analyzed for a possible spill-over to the circulation of regulated miRNAs from the vessel walls.Results
We identified 482 different miRNAs expressed in cerebral arteries post-SAH. Two miRNAs, miR-30a and miR-143, were significantly upregulated in cerebral arteries after SAH when compared to sham-operated animals. However, none of these exhibited significantly altered serum levels after SAH versus post-sham surgery. The most robust upregulation was seen for miR-143, which has several predicted targets and is a strong regulator of vascular morphology. We hypothesize that miR-30a and miR-143 may play a role in the vascular wall changes seen after SAH.Conclusions
We report that miR-30a and miR-143 in the cerebral arteries show significant changes over time after SAH, but do not differ from sham-operated rats at 24 h post-SAH. Although this finding suggests interesting novel possible mechanisms involved in post-SAH cerebrovascular changes, the lack of regulation of these miRNAs in serum excludes their use as blood-borne biomarkers for cerebrovascular changes following SAH.Electronic supplementary material
The online version of this article (doi:10.1186/s12864-015-1341-7) contains supplementary material, which is available to authorized users. 相似文献107.
Ongkana N Zhao XZ Tohno S Azuma C Moriwake Y Minami T Tohno Y 《Biological trace element research》2007,119(2):120-127
To elucidate compositional changes of the pineal body with aging, the authors investigated age-related changes of elements
in the pineal body. After the ordinary dissection by medical students was finished, the pineal bodies and seven arteries were
resected from the subjects ranging in age from 58 to 94 years. The element contents were determined by inductively coupled
plasma atomic emission spectrometry. It was found that a high accumulation of Ca and P occurred in the pineal bodies with
aging. Regarding the relationships among the elements, it was found that there were significant direct correlations among
the contents of Ca, P, and Mg. With regard to the relationships between the pineal body and the arteries, no significant correlations
were found in the Ca content between the pineal body and the arteries, such as the thoracic and abdominal aortas and the coronary,
common carotid, pulmonary, splenic, and common iliac arteries. 相似文献
108.
兔血管对He—Ne激光的反射、透射、吸收系数和散射相函数的研究 总被引:1,自引:0,他引:1
本文运用光生物学、基础医学以及物理学的基本理论 ,探讨了兔血管组织的激光传播特性 ,定量测定了兔血管组织的激光传输参量。采用标准积分球测量了兔血管组织样品在 632 .8nmHe Ne激光照射下的透射率 (T)和反射率 (R) ,推算吸收率 (A)。并把分光仪改装为光散射测量装置 ,测量了 632 .8nmHe Ne激光照射下 ,- 90°~ 90°散射角范围内的散射相函数S(θ) ,计算平均散射余弦 μ。结果表明 :兔动脉对He Ne激光的漫反射率比静脉的大 (P <0 .0 1 ) ,而透射率却明显比静脉小 (P <0 .0 1 ) ,而动脉的吸收系数明显地比静脉要小 ,He Ne激光对静脉的穿透深度明显比动脉的要大。兔动脉和静脉对He Ne激光有较强的反向散射 (μa<0 .5 ,μν<0 .5) ,且静脉的反向散射明显较动脉的要强 ,其相应的散射相函数S(θ)有着明显的差别。兔动脉和静脉对He Ne激光的反射、透射、吸收系数及散射相函数等光学性质的明显不同提示在应用He Ne激光进行血管疾病的治疗时应加以考虑。 相似文献
109.
Zerina Johanson 《Lethaia: An International Journal of Palaeontology and Stratigraphy》2002,35(2):169-186
Phylogenetic analyses frequently resolve the extinct group Placodermi at the base of the clade of jawed fishes (traditionally known as the Gnathostomata), with the jawless fish group Osteostraci as sister taxon to this clade. Both gnathostomes and osteostracans possess pectoral fins supported by a radial(s) articulating on a cartilaginous scapulocoracoid. Blood vessels and nerves pass by or through the scapulocoracoid to supply the musculature of the pectoral fin, and in the Osteostraci also pass through the postbranchial lamina backing the gill chamber before reaching the scapulocoracoid. This course also characterizes the placoderm group Antiarchi. Other placoderms retain the condition typical of other jawed fishes in which the scapulocoracoid, as well as the subclavian veins and arteries, are entirely posterior to the back wall of the gill chamber, lying within the internal region of the trunkshield. These observations suggest that these placoderm groups are more closely related to other jawed fishes than are the Antiarchi, challenging the monophyly of the Placodermi. 相似文献
110.
Yoshiyuki Tohno Setsuko Tohno Yumi Moriwake Cho Azuma Yoshiaki Ohnishi Takeshi Minami 《Biological trace element research》2001,82(1-3):21-28
To elucidate compositional changes of the arteries with aging, the authors investigated the relationships among average contents
of calcium, phosphorus, sulfur, and magnesium in the arteries by inductively coupled plasma-atomic emission spectrometry.
The arteries used were the thoracic and abdominal aortas, coronary, common carotid, anterior, middle and posterior cerebral,
vertebral, basilar, internal thoracic, axillary, radial, truncus celiacus, common, internal and external iliac, femoral, popliteal,
and umbilical arteries. It was found that high correlations were found between the average contents of calcium and phosphorus,
between the average contents of calcium and magnesium, and between the average contents of phosphorus and magnesium in the
arteries, but not between the average contents of sulfur and the other elements. These correlations revealed that as the content
of calcium and phosphorus increased in the arteries, the magnesium content increased simultaneously in the arteries, but the
sulfur content did not. It is likely that magnesium forms compounds with phosphorus in the arteries. 相似文献