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1.
In 30 experiments in order to specify the blood supply and conducting system in the dog heart, coronal arteries were injected with a contrasting mass that was followed by roentgenography and preparation of the coronal arteries. The topography and blood supply of the atrioventricular conducting system with application of prevital blood supply, and the left coronal artery is the main source of blood supply for all the parts of the cardiac atrioventricular conducting system.  相似文献   

2.
市场上的电子血压计一般均采用示波法,采用间接测量原理,其准确性难以提高。柯氏音法是血压测量的金标准,有望提高自动血压测量准确性,但柯氏音的降噪和识别是难题。因此,提出了基于柯氏音识别法的自动血压测量系统,该系统解决了降噪和识别的难题,通过对实时柯氏音信号的测试表明该系统可以有效地识别出柯氏音,得出收缩压和舒张压,识别精度高。且该系统成本低廉,测试实验均造作于Android系统的手机上,易于实现社区血压的健康管理和远程监控。  相似文献   

3.
Genesis and pathogenesis of lymphatic vessels   总被引:1,自引:0,他引:1  
The lymphatic system is generally regarded as supplementary to the blood vascular system, in that it transports interstitial fluid, macromolecules, and immune cells back into the blood. However, in insects, the open hemolymphatic (or lymphohematic) system ensures the circulation of immune cells and interstitial fluid through the body. The Drosophila homolog of the mammalian vascular endothelial growth factor receptor (VEGFR) gene family is expressed in hemocytes, suggesting a close relationship to the endothelium that develops later in phylogeny. Lymph hearts are typical organs for the propulsion of lymph in lower vertebrates and are still transiently present in birds. The lymphatic endothelial marker VEGFR-3 is transiently expressed in embryonic blood vessels and is crucial for their development. We therefore regard the question of whether the blood vascular system or the lymphatic system is primary or secondary as open. Future molecular comparisons should be performed without any bias based on the current prevalence of the blood vascular system over the lymphatic system. Here, we give an overview of the structure, function, and development of the lymphatics, with special emphasis on the recently discovered lymphangiogenic growth factors.  相似文献   

4.
The subcutaneous sinus (SCS) of hagfish is a large and seemingly expansible compartment. Hagfish have a high blood volume and more than 30% of this volume is contained within the sinus system. The rate of return of SCS blood to the central circulation is slow in animals at rest. Blood enters the branchial sinus system at papillae on the branchial vessels, but the routes of entry into the SCS are not fully understood.Hagfish have the lowest blood pressures with the Vertebrata. The low power requirement of the hagfish heart must contribute to the animal's low rate of energy consumption. However, this may be an incidental benefit associated with the need to prevent blood pressures from rising and thus forcing more blood into the sinus system. Low blood pressures appear to be essential for the functioning of the gill pouches. Bolus injections of saline into central blood vessels affect pressures for some time. This suggests that cardiac output is sensitive to venous filling pressures and that there must be mechanisms for controlling the partitioning of blood between the central circulation and the sinus system. It may not be correct to consider the low blood pressures of hagfish as a “primitive” character.  相似文献   

5.
This paper describes the aortic blood pressure as a function of aortic blood flow and the parameters of the blood and circulatory system. The method of performance involves the analogue of a multi-branched electrical to hydraulic transmission line applying graphical convolution to the blood flow-transform impedance relationship resulting in a theoretical pressure curve for the infinite aorta. The difference between the single pressure pulse and the computed adjusted infinite aorta pressure curve is described as the reflected wave. This reflected wave is then shown to be of reasonable configuration in time and velocity. The blood pressure is thus finally described completely by the physical parameters of the blood and the circulatory system and the blood flow.  相似文献   

6.
Within a day of gastrulation, the embryonic heart begins to beat and creates blood flow in the developing cardiovascular system. The onset of blood flow completely changes the environment in which the cardiovascular system is forming. Flow provides physiological feedback such that the developing network adapts to cue provided by the flow. Targeted inactivation of genes that alter early blood fluid dynamics induce secondary defects in the heart and vasculature and therefore proper blood flow is known to be essential for vascular development. Though hemodynamics, or blood fluid dynamics, are known to activate signaling pathways in the mature cardiovascular system in pathologies ranging from artherosclerosis to angiogenesis, the role in development has not been as intensively studied. The question arises how blood vessels in the embryos, which initially lack cells types such as smooth muscle cells, differ in their response to mechanical signals from blood flow as compared to the more mature cardiovascular system. Many genes known to be regulated by hemodynamics in the adult are important for developmental angiogenesis. Therefore the onset of blood flow is of primary importance to vascular development. This review will focus on how blood flow initiates and the effects of the mechanical signals created by blood flow on cardiovascular development.  相似文献   

7.
In contrast to the inability to demonstrate endotoxin detoxifying activity in either control rat blood, blood cells, plasma, or serum, the induction of mild endotoxemia or trauma resulted in a prompt and marked detoxifying activity in blood plasma or serum, but not in the cellular elements. The functional significance of the blood anti-endotoxin system was demonstrated by a capability for passive transfer and by its loss during severe traumatic shock. A role for the RES in elaboration of the blood anti-endotoxin system is postulated.  相似文献   

8.
In this work, we present a new version of the dilution-filtration system for rapidly deglycerolizing a large volume of cryopreserved blood. In our earlier system, one of the major problems was the damage induced to the red blood cells (RBCs) due to high osmolality change at the dilution point. Therefore, we devised a new system to solve this problem. First, we theoretically simulated the osmolality variation in the new system and the variation of the maximum and minimum volumes of the RBCs at the dilution point to examine the effects of operating parameters/conditions. Next, we experimentally validated the effects of these operating parameters by deglycerolizing porcine blood. The results show that when the initial NaCl concentration in the hypertonic solution is 18%, the volume of the hypertonic solution is 200 mL, and the flow rate of the filtrate is 50 mL/min, the system can effectively remove glycerin from 200 mL of porcine blood in 30 min, with ∼87% RBC survival rate and ∼73% RBC recovery rate. Our results indicated that in the new system the concentration and the volume of the hypertonic solution used to dilute the blood are the important parameters that need to be adjusted to reduce osmotic damage to the RBCs. In addition, a fast filtrate flow rate is highly recommended. This work can significantly contribute to the development of a more efficient and effective system for deglycerolizing large volumes of cryopreserved blood in clinic.  相似文献   

9.
This review focuses on the signaling system involving the Angiopoietin1/Tie2 receptor, which appears to be involved in the secondary stages of blood vessel formation. Although this system is crucial for blood and lymphatic vessel formation, identifying its precise role in embryonic and adult vascular biology has been a major challenge. The evidence for the key role of the Angiopoietin/Tie system is discussed, and some of the other members of the system (Ang2, Tie1) are mentioned. A comparison is made with the VEGF signaling system, which seems to provide a complementary, and somewhat more tractable, signaling system. Some of the basic unanswered questions concerning Tie/Angiopoietin biology and the secondary stages of blood vessel formation are also highlighted.  相似文献   

10.
凝血系统的瀑布机制揭示了凝血因子间的酶促级联反应过程。在级联反应中,各个因子间明显地存在着序关系,而这种序关系的全体构成了系统的序结构。从系统论的观点看,系统的结构是系统性质与功能的基础,因此,通过模型化方法以及利用凝血因子序结构图建立的序结构分析方法,是分析凝血系统各因子相互作用的有用的工具。对蛋白C及TFPI进行序结构分析,进一步阐明了这两种抑制剂对外源途径凝血的作用特点。  相似文献   

11.
Associations of the 11 bovine blood group systems with mastitis were examined in Red Danish dairy cattle. The mastitis status was followed during three lactational periods. A significant effect of the M blood group system on mastitis incidence was observed in the first and second lactation periods and a lower frequency of mastitis is found among animals lacking the M' factor as compared to those having the M' blood group factor. The significance of these results are discussed in view of the close relation between the M blood group system and the bovine lymphocyte antigens (BoLA), and the expected effect of eliminating the M' gene from the breed is estimated. Among the remaining 10 blood group systems, the T' system was the only system showing an overall effect on mastitis, and only in first and third lactation. However, the T' system was inconsistent with regard to the effect of the T' gene on the various mastitis diagnoses.  相似文献   

12.
Retarded heparin-35S clearance from the blood stream during activation of the blood anticoagulation system was observed. Under these conditions the half-life of heparin-35S increased from 1.6 h in control animals to 2.35 h in the animals after intravenous injection of a threshold dose of thrombin causing activation of the anticoagulation system. Retarded heparin-35S clearance from the blood stream during activation of the blood anticoagulation system is accompanied by increase of its absorption in the liver and in the auricular atrii.  相似文献   

13.
Association of the M blood group system with bovine mastitis   总被引:2,自引:0,他引:2  
Associations of the 11 bovine blood group systems with mastitis were examined in Red Danish dairy cattle. The mastitis status was followed during three lactational periods. A significant effect of the M blood group system on mastitis incidence was observed in the first and second lactation periods and a lower frequency of mastitis is found among animals lacking the M' factor as compared to those having the M' blood group factor. The significance of these results are discussed in view of the close relation between the M blood group system and the bovine lymphocyte antigens (BoLA), and the expected effect of eliminating the M' gene from the breed is estimated. Among the remaining 10 blood group systems, the T' system was the only system showing an overall effect on mastitis, and only in first and third lactation. However, the T' system was inconsistent with regard to the effect of the T' gene on the various mastitis diagnoses.  相似文献   

14.
Following the discovery of ABO blood group over 100 years ago, a variety of studies sought to determine whether different disease states are influenced by ABO inheritance. As oligosaccharide antigens, ABO blood group antigens are widely expressed on the membrane of red blood cells and tissue cells, as well as in the saliva and body fluid. It is by far the most important blood group system in human immunohematology and transfusion medicine. While, other than determining blood group phenotype, accumulating evidence indicates that ABO blood group is implicated in the development of a number of human diseases. This review mainly focuses on the association between ABO blood group and cardiovascular system risk, corona virus disease 2019 (COVID-19), affective disorders, allergic diseases, as well as cancers.  相似文献   

15.
目的:建立同时实现乙型肝炎病毒(hepatitisBvirus,HBV)、丙型肝炎病毒(hepatitisCvirus,HCV)、艾滋病病毒(humanImmunodeficiencyVirus,HIV)检测的多重核酸筛查系统。方法:以HBV、HCV、HIV的保守序列为模板设计特异性引物和探针,通过核酸自动提取系统结合一步法RT-PCR技术平台,优化相关反应体系和条件,建立多重多色实时荧光PCR检测血源性传播病毒的核酸筛查系统。将该系统用于101387例血浆样本的筛查。结果:本研究建立的核酸筛查系统特异性好,HBV灵敏度可以达到20IU/ml,HCV灵敏度可以达到100IU/ml,HIV灵敏度可以达到50IU/mL。结论:本研究建立的核酸筛查系统具有高度自动化、高灵敏度、低成本等特点,适合我国血站系统推广使用。  相似文献   

16.
An expression for oxidative potential (phi) of conservated blood is suggested proceeding from the assumption of the steady character of the system methemoglobin -- hemoglobin, oxihemoglobin included. This system is suggested to be responsible for the formation of phi in the blood. The equation qualitatively describes the experimental relation of phi on time at the contact of blood with air. Relationship between the changes of oxidative potential in the blood during its storage with the state of conservated blood hemoglobin is discussed. The experimental data show that measuring of the oxidative potential may be the basis for creating a control method for the state of conservated blood during its storage.  相似文献   

17.
本文提供了男、女两性共404人ABO、MN血型各表现型的35个体质特征测量数据,对血型和测量体征的关系进行了初步讨论。统计分析表明,不同血型群体的某些单个体征平均值之间有显著差异。对所调查的35个体征作整体分析,可见男性MN系统和女性ABO、MN系统各血型群体平均值之间差异显著。在MN血型系统,MN型群体的测量体征平均值低于M型和N型与MN基因型的杂合状态有密切关系。本文还分析了4个民族的血型资料,表明MN血型在ABO血型系统是随机分布的。  相似文献   

18.
Reversal of renovascular hypertension: role of the renal medulla   总被引:1,自引:0,他引:1  
The fall in blood pressure, which occurs when renovascular hypertension is corrected surgically, offers a means of elucidating the factors responsible for blood pressure control. When Goldblatt two-kidney, one-clip hypertension in the rat is reversed by unclipping the renal artery, or by removal of the ischaemic kidney, restoration of normal blood pressure is due to a fall in peripheral resistance. This is associated with sodium retention and cannot be modified by inhibition of the renin-angiotensin system. The fall is, however, partially inhibited by chemical removal of the renal medulla by means of 2-bromo-ethylamine hydrobromide. When normal rats are chemically medullectomized, moderate hypertension is produced, which cannot be attributed to the renin-angiotensin system or sodium retention. It is concluded that a renomedullary vasodepressor system is ablated by chemical medullectomy: further, this system plays a role in the surgical correction of Goldblatt hypertension.  相似文献   

19.
We attempted a new approach based on a modern dynamical system theory to reconstruct the arterial blood pressure signals in relation to heart rate fluctuations of developing chick embryos. The dynamical systems approach in general is to model a phenomenon that is presented by a single time series record and approximate the dynamical property (e.g. heart rate fluctuations) of a system based only on information contained in a single-variable (arterial blood pressure) of the system. The time-series data of the arterial blood pressure was reconstructed in 3-dimensional space to draw characteristic orbits. Since the reconstructed orbits of the blood pressure should retain information contained in the pressure signals, we attempted to derive instantaneous heart rate (IHR) from the reconstructed orbits. The derived IHR presenting HR fluctuations coincided well with the IHR obtained conventionally from the peak-to-peak time intervals of the maximum blood pressure. Movements of the reconstructed orbits of the arterial blood pressure in 3-dimensional space reflected HR fluctuations (i.e. transient decelerations and accelerations).  相似文献   

20.
本文首先建立了相应于Lamula与Griffin的凝血动力系统瀑布模式的非线性数学模型.并使用分叉方法较深入地分析了该系统的定态平衡解与动态解的稳定性与全局吸引子.通过动力学分析,我们从理论上证明了存在外源性路径启动的触发阈值及瀑布机制达到终态的细节:趋于一个全局吸引子.  相似文献   

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