The production of blood cell stasis and endothelial damage in the blood vessels of chick embryos treated with ultrasound in a stationary wave field

Blood cell flow can be arrested in living tissue by exposing it to ultrasound in a stationary wave field. The cells form bands at half wavelength intervals in the blood vessels. The process is generally reversible, and during dissociation the hands assume a parabolic profile in vessels where flow is laminar. Under optimum conditions, in the chick embryo, the minimum intensity required for stasis is less than 0·5 Wcm^?2 at 3 MHz with continuous irradiation. The threshold intensity varies with the type, size and orientation of the vessel, and with the heart rate. Electron microscopy reveals damage to some of the endothelial cells lining the embryonic vessels in which stasis has occurred. Methods of avoiding stasis are suggested and the mechanisms of stasis are discussed.     

A new immobilisation method to arrange particles in a gel matrix by ultrasound standing waves

Ultrasonic forces may be used to manipulate particles in suspension. For example, a standing wave ultrasound (US) field applied to a suspension moves the particles toward areas of minimal acoustic pressure, where they are orderly retained creating a predictable heterogeneous distribution. This principle of ultrasonic retention of particles or cells has been applied in numerous biotechnological applications, such as mammalian cell filtering and red blood cell sedimentation. Here, a new US-based cell immobilisation technique is described that allows manipulation and positioning of cells/particles within various nontoxic gel matrices before polymerisation. Specifically, gel immobilisation was used to directly demonstrate that the viability of yeast cells arranged by an US standing wave is maintained up to 4 days after treatment. The versatility of this immobilisation method was validated using a wide range of acoustic devices. Finally, the potential biotechnological advantages of this US-controlled particle positioning method combined with gel immobilisation/encapsulation technology are discussed.     

腹内血管自发性破裂出血的临床诊治体会

目的：探讨腹内血管自发性破裂出血的诊断和治疗方法。方法：对11例腹内血管自发性破裂出血病人进行回顾性分析，并对其发生原因，诊断和治疗方法进行分析讨论。结果：高血压、动脉粥样硬化和肝硬化门静 脉高压症是本病的主原原因。腹痛和失血是主要临床表现。预后取决于出血的速度、出血量及是否得到及时的诊断和治疗。及时手术，尽可能寻找并结扎出血的血管是治疗的关键。结论：提高对本病的认识，对不明原因的腹腔出血应尽早手术探查。     

Doppler methods for quantitative measurement and localization of peripheral arterial occlusive disease by analysis of the blood flow velocity waveform

Errors concerned with the use of continuous wave Doppler ultrasound for the quantitative assessment of peripheral arterial occlusive disease by analysis of the blood flow velocity waveform are briefly examined. It is shown that, while some of the simpler signal processing techniques are inadequate, techniques such as real-time frequency analysis of the Doppler signal can yield information of quantitative value. A new multifilter system is described that yields the instantaneous maximum velocity waveform. From the results of preliminary patient studies using this system, it is concluded that clinically significant peripheral arterial disease can be quantified and regionally localized.     

The muscarinic receptor subtypes in human blood vessels

Acetylcholine (ACh) may induce the relaxation and the contraction of human blood vessels. These effects involve the activation of muscarinic receptors located on endothelial or smooth muscle cells. In humans and animals, five subtypes of muscarinic receptors (M1-M5) have been identified. In the particular case of human blood vessels, the M3 subtype seems to be prevalent on endothelial cells as well as on smooth muscle cells. However, the M1 subtype may be specific for the pulmonary vascular endothelium. In contrast, the M4 subtype has not been described in human vessels. These conclusions are, however, based on a limited number of studies and further work is needed in this area of research. Although muscarinic receptors may not be the only receptors involved in hypertension, the development of specific agonists for M1 receptors may be useful to counteract any elevation of blood pressure in the pulmonary circulation.     

急性动脉栓塞取栓后回心血经血液净化后回输的研究

目的 探讨将急性动脉栓塞取栓后的回心血经血液净化后回输的可能性。方法 将回心血收集、稀释10倍后用血滤器予以超滤、浓缩后经浅静脉回输。结果 超滤浓缩后血钾、血乳酸浓度呈显性降低，回输后无各种并发症发生。结论 急性动脉栓塞取栓后回心血经血液净化回输是一种安全、有效的预防代谢障碍综合征的方法。     

On the measurement of the mean velocity of blood flow over the cardiac cycle using Doppler ultrasound

A number of modern duplex scanners now have facilities for determining volumetric blood flow through intact vessels. The methods these machines use to arrive at an answer must presuppose a number of conditions which may not be met in practice. This paper examines the effect that nonuniform insonation of the target blood vessel (using continuous wave or wide-gate pulsed ultrasound) has on the mean velocity, as determined using mean, root mean square (RMS) and maximum frequency processors. It is shown that for a given beam/vessel geometry the error is dependent only on the shape of the mean component of the velocity profile which, depending on the arterial site, may be flat, parabolic or intermediate. Mean processors may overestimate the mean velocity of established flow by up to 33%, but this could be turned to advantage when it is impracticable to insonate a vessel uniformly. Maximum frequency processors are of value when either plugflow or fully established flow of low pulsatility is present in the target vessel. In the first case the mean flow is the same as the maximum flow, while in the second the mean flow is half the time averaged maximum flow, irrespective of the size and shape of the ultrasound beam. RMS processors are probably best avoided in volumetric flow measurement applications.     

Transcutaneous assessment of arterial elasticity

A mathematical model is outlined which describes the elastic modulus of an arterial segment in terms of the changes in phase of the harmonic components of the maximum blood velocity waveforms recorded at the extremities of the segment under study. An experimental method of obtaining the information transcutaneously using ultrasonic Doppler flow meters is described. Twelve subjects (8 male, 4 female) were taken and each subjected to whole body tilts feet down through 45°. Simultaneous measurements were made of the elastic constant and pulse wave velocity between the popliteal artery at the back of the knee and the posterior tibial at the side of the ankle in both the horizontal and tilted positions. A quantitative relationship was obtained between the elastic constant and the pulse wave velocity. A second group of ten males was taken and examined at weekly intervals over a period of one month. On each occasion they were tilted feet down through 45°; measurements were made of central arterial blood pressure and pulse wave velocity over the length of the lower limb. The elastic constant and mean blood pressure in the segment were calculated for both the horizontal and tilted position. The results obtained were compared with those reported elsewhere.     

Color coded ultrasonic differential velocity arterial scanner (Echoflow)

A scanning system is described which is capable of making a two dimensional display of the blood flowing in arteries. It has been especially designed for display of the carotid bifurcation but can be adapted for other blood vessels.Normally it uses continuously generated energy and detects the Doppler shifted signals from the blood flowing in the arteries at peak velocity as the arterial pulse propagates through the segment of vessel being scanned. The system is directional so that flow in only a single direction with reference to the beam is displayed at any one time. The Doppler shifted signals reflected by the blood flowing at peak velocity are detected by filters with varying frequency ranges. Signals from each filter activated are color-coded. The color display is made from the filter activated by the highest Doppler frequency shifted signals. Thus the arteries are displayed by colors corresponding to the highest peak velocities in their segments. Stenotic areas where peak velocities will be greater than in non-stenosed regions will thus be displayed by colors differing from that used to represent normal peak velocities.These regions of increased peak velocities correlate reliably in 95% of cases with arterial stenoses occluding more than 74% of the arterial diameter. Occluded vessels which do not appear at their appropriate position on the image are also reliably displayed in 95% of cases. The display of normal carotid bifurcations by normal colors in the Doppler scan is also reliable in 93% of cases but the display of slightly increased velocities may result from haemodynamic causes as often as from localized small stenoses.     

激光扫描共聚焦显微镜观察脑组织中血浆蛋白分布在损伤早期的改变

目的：观察脑组织中血浆蛋白分布在损伤早期的改变。方法：用免疫组织化学染色显示人脑组织中的白蛋白、IgG和IgM，用激光扫描共聚焦显微镜观察这些血浆蛋白的分布在损伤早期的改变。结果：政党脑组织中，白蛋白、IgG和IgM闰于血管内，未见血浆蛋白阳性神经细胞，在损伤早期，脑组织中出现大量白蛋白，IgG及IgMB阳性神经细胞和社会纤维，结论：脑组织中血浆蛋白分布在损伤早期发生了改变，提示血脑屏障和神经细胞均有不同程度的损伤。     

Peripheral vascular reactions in anaphylaxis of the mouse

Pronounced vascular changes occurring in the ears and claws of mice during anaphylactic shock are described. Practically at once after a foreign serum (pig, horse, or rabbit) enters the blood stream of sensitized animals both the arterial and venous vessels undergo marked, local or generalized constriction in the organs mentioned. Usually spasm of the vessel walls occurs simultaneously in the arteries and veins, but it may appear first in the arteries, or occasionally in the veins. When venous spasm precedes arterial spasm, the true capillaries become distended with cells; if the reverse order holds, the ears appear bloodless. There is no active constriction or dilatation of capillaries; the capillary behavior follows passively the changes in the large vessels. Peripheral vascular spasm occurs while the carotid blood pressure is high, but a few minutes later, while this still holds true, the ear vessels begin to relax and the circulation is resumed. Shortly afterwards the blood pressure falls to levels far below normal, but the vessels remain open. If the circulation of one ear is obstructed while anaphylactic shock is produced, no vascular spasm occurs in it. Release of the obstruction during the animal's recovery results in belated constriction of the blood vessels of this ear although by now the vessels in the other ear are dilated and the general systolic blood pressure is very low. The vascular reactions in the ears appear to be uninfluenced by the blood pressure in the large vessels, and they are not a response to nervous stimuli. They are local in origin. The vascular changes are often not clearly perceptible in the gross but are plainly to be seen under a low power of the microscope. They occur in some sensitized mice exhibiting no manifest signs of shock, differing only in degree from the changes taking place when shock is severe or fatal.     

A theoretical framework for quantifying blood volume flow rate from dynamic angiographic data and application to vessel-encoded arterial spin labeling MRI

Angiographic methods can provide valuable information on vessel morphology and hemodynamics, but are often qualitative in nature, somewhat limiting their ability for comparison across arteries and subjects. In this work we present a method for quantifying absolute blood volume flow rates within large vessels using dynamic angiographic data. First, a kinetic model incorporating relative blood volume, bolus dispersion and signal attenuation is fitted to the data. A self-calibration method is also described for both 2D and 3D data sets to convert the relative blood volume parameter into absolute units. The parameter values are then used to simulate the signal arising from a very short bolus, in the absence of signal attenuation, which can be readily encompassed within a vessel mask of interest. The volume flow rate can then be determined by calculating the resultant blood volume within the vessel mask divided by the simulated bolus duration. This method is applied to non-contrast magnetic resonance imaging data from a flow phantom and also to the cerebral arteries of healthy volunteers acquired using a 2D vessel-encoded pseudocontinuous arterial spin labeling pulse sequence. This allows the quantitative flow contribution in downstream vessels to be determined from each major brain-feeding artery. Excellent agreement was found between the actual and estimated flow rates in the phantom, particularly below 4.5 ml/s, typical of the cerebral vasculature. Flow rates measured in healthy volunteers were generally consistent with values found in the literature. This method is likely to be of use in patients with a variety of cerebrovascular diseases, such as the assessment of collateral flow in patients with steno-occlusive disease or the evaluation of arteriovenous malformations.     

上皮性低分化卵巢癌的微血管超微结构特征与血管内皮生长因子的细胞器定位研究

目的探讨上皮性低分化卵巢癌的微血管超微结构特征及血管内皮生长因子(VEGF)在其微血管上皮细胞的显微分布与定位。方法收集新鲜卵巢癌手术标本5例,常规透射电镜制样后观察其癌细胞的超微结构,微血管分布结构及新生血管形成,胶体金标记免疫电镜技术时VEGF进行细胞器水平定位。结果透射电镜下可见癌细胞大小形态不一,细胞表面有微绒毛,癌细胞成群分布,癌细胞间有细胞连接形成,核畸形,癌组织内血管丰富并新生血管形成,血管壁有缺损;免疫电镜检测VEGF定位在内质网,溶酶体及线粒体内或其膜上。结论肿瘤的血管发生是肿瘤迅速增殖和转移的重要条件,上皮性低分化卵巢癌的微血管超微结构特征及VEGF的亚微分布与其生物学行为,临床预后间存在一致性。     

Software analysis of 20 mhz pulsed doppler quadrature data

A computer software procedure for processing quadrature data obtained from a 20 MHz pulsed Doppler system is described and the quality of results obtained is illustrated. The system is implemented on a standard laboratory minicomputer system. Software flexibility expands use of this high resolution device for measuring blood velocity to larger vessels than previously demonstrated. Techniques for dealing with high frequency aliasing, time delays, digital filtering and sampling intervals are included.     

Enzymes in lymph: a review

Lymph is the minute net volume of contending hydrostatic and osmotic capillary forces. It is built up extravasculary in tissues and reaches the intravasal space by definite lymph collecting vessels, which enter the venous system at the angulus venosus at the root of the neck. Sampling methods for lymph from individual tissues or from lymph collecting vessels of man and various animals are cited and the preparation of lymph for enzymatic analysis is described. The extracellular distribution and transport of enzymes is important for diagnostic enzymology, because enzymes released from cells in continuous physiological processes, or after injury to the tissue, reach the intravasal space mainly via the lymphatics. This is evident from the high lymph-plasma ratios of diagnostically important enzymes. The type of enzyme transport (lymphatic or by direct interstitial-venous entry) depends on the heterogeneity of the capillary barrier characteristic of the different organs. The permeability is extremely high in liver, i.e. enzymes in hepatic lymph originate mainly from blood, which they have reached through the large openings in the sinusoidal endothelial lining; in contrast the permeability is extremely low in skeletal muscle, where lymphatic transport therefore predominates. The phenomenon of increased enzyme activities in plasma after physical exertion is explained by alterations of lymph flow. A table gives a survey of enzyme activities, lymph-plasma quotients, and lymph flow from lymph vessels of various tissues as well as from the lymph collecting vessels of man and animals, with comments on the signficance for diagnostic enzymology.     

应用超声微泡直接测量微小血管血流速度

目的应用超声微泡直接、非侵入性测量微小血管的血流速度。方法体外实验：用硅胶管建立一种模拟血流的体外模型,应用谐波超声追踪超声微泡在管内的流动,并录像。用“DFY型超声图像定量分析诊断仪”分析每帧中微泡的位置,以微泡的移动距离除以时间,得到微泡的移动速度。体内实验：建立9只大鼠直肠癌移植瘤模型,用与体外实验相同的方法测量大鼠直肠癌移植瘤内微小血管的血流速度。肿瘤切片HE染色,显微镜下测量肿瘤血管内径。结果体外实验：在体外模型中的血流标准速度分别为37．14mm／s,21．01mm／s和4．35mm／s,应用本法测得的血流速度为（37．03±2．45）1mm／s、（24．40±2．10）mm／s和（4．86±0．45）mm／s,两者间无统计学差异。体内实验：在肿瘤模型中所测得的小血管内血流速度为5．38～20．82mm／s;HE染色发现9个肿瘤外周的最大血管内径平均为（142．76±24．03）μm,肿瘤内部的最大血管内径平均为（40．82±11．17）μm。这些小血管在常规多普勒超声下不能被探及。结论本实验测试了一种直接测量小血管的血流速度的新技术。结果表明,应用超声微泡可以准确测量小血管内的血流速度。经过对自动化跟踪技术的优化,这种新技术极有可能成为临床上非侵入性直接测量小血管血流速度的有效工具。     

Blood flow velocity changes in migraine attacks-a transcranial Doppler study

A pulsed Doppler device was used to measure blood flow velocities in the common carotid artery, the extracranial part of the internal carotid artery, the external carotid artery, the middle cerebral artery, and the anterior cerebral artery in 31 migraineurs without aura (n = 27) and with aura (n = 4), both during and outside an attack. The aims were to compare blood flow velocity during and between migraine attacks and to study asymmetries of the blood flow velocity. Compared with blood flow velocity values obtained in the attack-free interval, blood flow velocity was lower during attacks without aura in both common carotid arteries, but not in the other extra- and intracranial vessels which were examined. However, during attacks of migraine with aura, blood flow velocity tended to be lower in all examined vessels. There were no asymmetries of the blood flow velocity. We suggest that during migraine attacks without aura there is a dissociation in blood flow regulation in the common carotid and middle cerebral arteries.     

TCD 新指标对血管性头痛病的诊断价值

目的：用TCD新指标对血管性头痛患者进行脑血管负荷的检测和对比研究,阐明TCD在脑血管性头痛监测中的价值。方法：采用TCD与计算机连用的方法,对以上两组146例的1606条脑血管进行新指标的对照检查。结果：106例血管性头痛患者均有不同程度的血流动力学异常,且随年龄增加病变程度更为明显。结论：脑血管收缩平均速度、反弹高度、紧张度、压力指数、缓慢指数、血管负荷是临床诊断血管性头痛病的新指标。     

超声多普勒血流检测诊断胎儿脐带绕颈：附75例分析

本文应用超声血流分析仪对414例妊娠30—42w的孕妇进行了脐动脉血流检测,诊断脐带绕颈75例,经分娩证实72例,敏感性96%,特异性94.2%。本文还就胎儿颈部脐血流检测诊断脐带绕颈的部位进行了分析,提出胎儿颈部背、腹两侧皆有典型脐动脉血流波时敏感性、特异性最高,只有颈部腹侧有典型脐动脉血流波时敏感性,特异性最低。其次提出多普勒诊断胎儿脐带绕颈随孕周的增加准确性增加,多普勒诊断脐带绕颈的同时所检测脐动脉s/d比值可预测胎儿预后,特别是s/d比值连续升高时对推测脐带绕颈的松紧有所帮助,为临床选择恰当的分娩方式提供了更多指标,对降低围产儿死亡率有重要意义。