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1.
At the physiological pH 7.4, the zeta potential of the normal red blood cell in 1.5% glycine buffer was found to be ?52 mv, whereas that of sickling erythrocytes is ?45 mv. Addition of spermidine to normal red blood cells reduced the zeta potential by approximately 20 mv. In sickling red blood cells, where the polyamine content is determined to be 5 to 6 times greater than in the normal erythrocyte, addition of spermidine reduced the zeta potential by only 5 mv, indicating that little more polyamine binding occurs. The polyamine content of whole blood taken from 24 patients having sickle cell anemia was found to be more than ten times that of whole blood from normal donors. Binding of polyamines to the normal red blood cell was analyzed from the surface charge potential variation as a function of polyamine concentration and the apparent binding constant determined to be 130 d1/g. The difference in the electrokinetic properties of normal and sickling red blood cells in this system may be attributed, in part, to a variation in the polyamine content of the two types of erythrocytes.  相似文献   

2.
Changes in response to heat in the dermal, subcutaneous, and muscle blood flow in the hands of 10 patients with hand infections were studied using 133Xe and recording of clearance data. A further 15 normal hands were studied in a similar manner. The application of topical heat to normal hands resulted in a decrease in the dermal blood flow (p less than 0.001), an increase in the subcutaneous blood flow (p less than 0.05), and perhaps an increase in the intramuscular flow (p less than 0.1). This suggests that surface heat promotes a shunting of the blood from the skin to deeper tissue layers. In infected hands, the blood flow was found to be significantly increased threefold in the intradermal circulation (p less than 0.01) and eightfold in the subcutaneous circulation (p less than 0.03) when compared to controls. In contrast to normal hands, in the infected hands, the blood flow decreased in all three compartments by 50 percent following application of heat. The blood flow of the normal hand in patients with infection did not respond to heat in the normal pattern. We conclude that the application of local heat to normal tissues results in shunting of blood flow from superficial tissues such as dermis to deeper ones such as subcutaneous fat and muscle. In infected tissues, the blood flow was found to be much higher than normal; however, the traditional belief in the improvement in blood flow by the application of heat was not confirmed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

3.
Levels of mercury distribution in placenta, amniotic sac and foetus and those in brain and liver of maternal acatasaemic mice were higher than those of normal, respectively. The levels of mercury distribution in the blood and lungs of maternal acatalasaemic mice exposed to metallic mercury vapor were also lower than those of normal. Mercury concentrations in placenta and foetus of acatalasaemic mice following exposure to metallic mercury vapor were higher than those of normal. Maternal acatalasaemic mice had decreased levels of mercury in the blood than those of normal mice. Thus, the placenta/blood or foetus/blood ratio of mercury concentration in acatalasaemic mice was significantly higher than that in normal mice. Similarly the brain/blood or liver/blood ratio of maternal acatalasaemic mice was higher than that of normal mice. These results suggest that metallic mercury in the blood readily passed through the blood-brain, blood-foetus barriers. In contrast to the results on exposures of mice to metallic mercury, the foetus/maternal blood ratio of mercuric concentration in the acatalasaemic mice following injection of mercuric chloride was similar to that in the normal mice. Moreover, the foetus/maternal blood ratio of mercury concentration in acatalasaemic or normal mice injected with mercuric chloride was lower than those in acatalasaemic or normal mice exposed to metallic mercury.  相似文献   

4.
Four subjects were studied during exercise at 50% of maximum oxygen uptake after a normal diet, after a low carbohydrate (CHO) diet following exercise-induced glycogen depletion, and after a high CHO diet. This regime has previously been shown to cause changes in the amount of glycogen stored in the exercising muscles. Metabolic and respiratory parameters were measured during the exercise. The respiratory exchange ratio, blood lactate, blood pyruvate, blood glucose and plasma triglycerides were lower than normal following the low CHO diet and higher than normal following the high CHO diet. Plasma free fatty acids and plasma glycerol were higher than normal after the low CHO diet and lower than normal after the high CHO diet. The contribution of CHO to metabolism was less than normal after the low CHO diet and greater than normal after the high CHO diet. The altered availability of FFA does not appear to be a result of the variations in the blood lactate content.  相似文献   

5.
The effect of a static magnetic field on human erythrocytes at different hemoglobin states (normal, oxidized and reduced hemoglobin) was investigated. Three different blood samples, normal, iron deficiency anemic and beta thalassemia minor, were studied. Measurements of the magnetization curves of the erythrocytes for all blood samples in all states showed diamagnetic behavior; however, oxidation was found to enhance this behavior. These measurements have also shown that the normal and iron deficiency samples in the reduced states exhibit a less diamagnetic response in comparison with the normal state. This result indicates that the reduction process gave rise to a paramagnetic component of the magnetization. Analysis of the measured paramagnetic behavior, using a Brillouin function, gave an effective magnetic moment of 8 muB per reduced hemoglobin molecule for both normal and anemic samples. This result shows that both anemic and normal blood have similar magnetic behavior and the only difference is the number of hemoglobin molecules per erythrocyte. For the beta thalassemia minor blood sample, magnetic measurements showed that both the normal and reduced states have almost the same diamagnetic behavior. However, this diamagnetic response is less than that for the normal state of the iron deficiency anemic sample. This result may indicate a low oxygen intake for the blood in the normal state for the beta thalassemia minor blood. All magnetic measurements were made using a vibrating sample magnetometer using field steps of 0.001 T from 1 T to -1 T.  相似文献   

6.
Oral administration of carnitine in normal and diabetic subjects showed a marked decrease in the level of blood glucose during the oral glucose tolerance test (OGTT) except for the three hour samples in diabetic subjects, while a decrease in the level of subsequent blood pyruvate samples was observed during the OGTT in normal and diabetic subjects after the administration of carnitine. During the OGTT, the peak of blood glucose and blood pyruvate level was generally delayed in the diabetic subjects. Furthermore, the mean blood pyruvate levels were elevated above those of normal subjects during the late stages of the test. The mean levels of blood glucose and blood pyruvate of all samples after the administration of carnitine were significantly higher in diabetics than the corresponding values in noramls. Carnitine administration decreased the total blood amino acid nitrogen level only in diabetic subjects. Carnitine caused a highly significant increase in the activity of serum alanine aminotransferase in normal and diabetic subjects, while it had no effect on the activity of serum aspartate aminotransferase. In goats, the level of blood glucose during the intravenous glucose tolerance test (IVGTT) was not affected by carnitine (1,3 or 6 mg/kg body weight). Carnitine in all doses used had no effect on the total blood amino acid nitrogen during the IVGTT, or on the activity of serum alanine aminotransferase and serum aspartate aminotransferase in the fasting samples. Acetyl-D,L-beta-methylcholine had no effect on the level of blood glucose, total blood amino acid nitrogen, the activity of serum alanine aminotransferase or serum aspartate aminotransferase in normal and diabetic subjects. The level of blood pyruvate decreased both in normal and diabetic subjects, in the samples that represented the peak of the curve. Glycine betaine had no effect on blood glucose, pyruvate, total blood amino acid nitrogen and the activity of serum alanine aminotransferase or serum aspartate amino transferase in normal and diabetic subjects or in goats.  相似文献   

7.
目的建立清洁级SD大鼠血液生理生化正常值。方法应用动物芯片血球计数仪测试常规血细胞计数;采用全自动生化测定仪对清洁级SD大鼠的血液28项生化指标进行测定,并进行统计分析雌雄差异显著性检验。结果建立了清洁级SD大鼠血液生理和28项血液生化参考值,ALB、AST/ALT、AG雌雄之间差异显著;血液血球计数雌雄差异不显著。结论比较详细的建立了清洁级SD大鼠的血液生理生化指标参考值,为其应用提供基础数据。  相似文献   

8.
The temperature dependence of ATPase activities and stearic acid spin label motion in red blood cells of normal and MH-susceptible pigs have been examined. Arrhenius plots of red blood cell ghost Ca-ATPase and calmodulin-stimulable Ca-ATPase activities were identical for both normal and MH erythrocyte ghosts. Arrhenius plots of Mg-ATPase activity exhibited a break (defined as a change in slope) at 24 degrees C in both MH and normal erythrocyte ghosts. However, below 24 degrees C the apparent activation energy for this activity was less in MH than normal ghosts. To determine whether breaks in ATPase Arrhenius plots could be correlated with changes in the physical state of the red blood cell membrane, the spin label 16-doxyl-stearate was introduced into the bilayer of both erythrocyte ghosts and red blood cells. With both ghosts and intact cells, at each temperature examined, the mobility of the probe in the lipid bilayer, as measured by electron paramagnetic resonance, was greater in normal than in MH membranes. While there were no breaks in Arrhenius plots for probe motion in the erythrocyte ghosts, the apparent activation energy for probe motion was significantly greater in normal than in MH ghost membranes. While there was no break in the Arrhenius plot of probe motion in normal intact red blood cell membranes, there were breaks in the Arrhenius plot of probe motion at both 24 and 33 degrees C in intact MH red blood cell membranes. Based on the altered temperature dependence of Mg-ATPase activity and spin probe motion in membranes derived from MH red blood cells, we conclude that there may be a generalized membrane defect in MH pigs which is reflected in the red blood cell as an altered membrane composition or organization.  相似文献   

9.
Oxygen tension levels and red cell velocities for the flow of sickle-cell blood in the capillaries are determined by using the Krogh model for oxygen transport and lubrication theory for the cell motion. The coupling and interaction between these arises from the red cell compliance, which is assumed to vary with the oxygen concentration. Microsieving data is used to establish an upper bound for this relationship. Calculations are carried out for a range of capillary sizes, taking into account the rightward shift of the oxyhemoglobin dissociation curve and the reduced hematocrit of sickle-cell blood, and are compared to, as a base case, the flow of normal blood under normal pressure gradient. The results indicate that under normal pressure gradients the oxygen tensions and cell velocities for sickle blood are considerably higher than for normal blood, thus acting against the tendency for cells to sickle, or significantly change their rheological properties, in the capillaries. Under reduced pressure gradients, however, the concentrations and velocities drop dramatically, adding to the likelihood of such shape or flow property changes.  相似文献   

10.
Concentration of metallic mercury in the arterial blood was higher in acatalasemic mice after exposure to 3.45 mg/m3 for 10 minutes in comparison with normal mice, whereas concentration of mercuric ion was lower in acatalasemic mice than in normal mice. Thus, the ratio of metallic mercury to total mercury in the arterial blood of acatalasemic mice was 5.86 +/- 3.61%, which was statistically significantly higher than the value (1.36 +/- 0.65%) of corresponding normal mice. The mercury concentration and distribution in the brain and liver of acatalasemic mice were higher than those in normal mice. Data indicate that the concentration of metallic mercury in the arterial blood of acatalasemic mice was higher than that of normal mice and that metallic mercury soluble in lipids is likely transferred to the brain and liver from the blood. Conclusively, metallic mercury in the arterial blood is the biologically active form for transferring mercury from blood to organs.  相似文献   

11.
目的:为制定中国中年女性红细胞计数正常参考值的统一标准提供科学依据.方法:收集了中国331个单位用显微镜计数法测定的41003例中年女性红细胞计数正常参考值,运用相关分析和回归分析的方法,研究了其与八个地理因素的关系.结果:发现中年女性红细胞计数正常参考值与中国地理因素之间有很显著的相关关系(F=364.76,P=0.000).用逐步回归分析的方法推导出了一个回归方程:Y^=4.184+0.0002421X1-0.02921X4+0.0002582X7+0.08144X8±0.47.结论:如果知道了中国某地的地理因素,就可以用回归方程计算这个地区的红细胞计数正常参考值.依据红细胞计数正常参考值与地理因素的依赖关系,把中国分为八个区.  相似文献   

12.
The stable fly hemolymph was analyzed after a blood meal. The hemolymph volume increased to approximately three times the pre-feeding level 3–6 h after a blood meal and gradually returned to normal 18 h after the blood meal. The osmotic pressure decreased approximately 10% following a blood meal and gradually returned to normal with a pattern that was a mirror-image of that of the hemolymph volume. Concentrations of cations and anions are not directly affected by the ingested blood, indicating a possible selective excretory mechanism.  相似文献   

13.
In this paper, Doppler continuous-wave analysis of blood velocity in the internal mammary artery, anastomosed to the left coronary vascular bed in humans who have undergone myocardial revascularization, is proposed as a non-invasive technique to study coronary blood flow during physiological procedures which cause it to change. Blood velocity curves obtained in normal and anastomosed internal mammary arteries were compared during hyperventilation and the Valsalva manoeuvre. During hyperventilation, blood velocity increased in the normal mammary but not in the anastomosed artery. During the expiratory effort of the Valsalva manoeuvre, the mean blood velocity decreased in the normal mammary artery but it did not change significantly in the anastomosed artery. Variations in the mean velocity were largely prevented by simultaneous and well-balanced increases and decreases in the diastolic and systolic velocities, respectively.  相似文献   

14.
Redistribution of blood flow away from resting skeletal muscles does not occur during anemic hypoxia even when whole body oxygen uptake is not maintained. In the present study, the effects of sympathetic nerve stimulation on both skeletal muscle and hindlimb blood flow were studied prior to and during anemia in anesthetized, paralyzed, and ventilated dogs. In one series (skeletal muscle group, n = 8) paw blood flow was excluded by placing a tourniquet around the ankle; in a second series (hindlimb group, n = 8) no tourniquet was placed at the ankle. The distal end of the transected left sciatic nerve was stimulated to produce a maximal vasoconstrictor response for 4-min intervals at normal hematocrit (Hct.) and at 30 min of anemia (Hct. = 14%). Arterial blood pressure and hindlimb or muscle blood flow were measured; resistance and vascular hindrance were calculated. Nerve stimulation decreased blood flow (p less than 0.05) in the hindlimb and muscle groups at normal Hct. Blood flow rose (p less than 0.05) during anemia and was decreased (p less than 0.05) in both groups during nerve stimulation. However, the blood flow values in both groups during nerve stimulation in anemic animals were greater (p less than 0.05) than those at normal Hct. Hindlimb and muscle vascular resistance fell significantly during anemia and nerve stimulation produced a greater increase in vascular resistance at normal Hct. Vascular hindrance in muscle, but not hindlimb, was less during nerve stimulation in anemia than at normal Hct.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
Anaemia can be induced in Rainbow trout by removing 12 % of the blood volume by cardiac puncture. Recovery from such an anaemia has been monitored in both normal and splenectomized fish. After the bleeding there is a decrease in red cell numbers, haematocrit and blood haemoglobin concentration. Although recovery in normal trout was not complete within 27 days, which was the period of the observations, it was seen as a replenishing of red cell numbers, haematocrit and blood haemoglobin concentration. Mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC), both depressed by the bleeding, did not appear to recover during the experimental period.
Splenectomy reduced erythropoietic intensity. After bleeding all the parameters studied were more depressed than those found in normal trout, and recovery was not noted. Blood haemoglobin and red cell numbers did not have the same post-bleeding pattern as normal individuals; MCH and MCHC values remained markedly depressed.
Splenic involvement was further demonstrated by bleeding trout for a second time from both normal and splenectomized groups. In contrast to the response of normal animals, there was a further deterioration of red cell numbers and blood haemoglobin concentration in splenectomized individuals.  相似文献   

16.
E Walitza  I Anadere  H Chmiel  S Witte 《Biorheology》1988,25(1-2):209-217
The dependence on hematocrit of whole blood viscoelasticity must be considered in order to compare pathological blood samples to normal ones. If one wants to calculate the measured values to a standard hematocrit value, the hematocrit dependence for the pathological sample must be available. As the latter however is unknown, the same dependence is assumed for both normal and pathological blood samples. To prove the validity of this assumption, hematocrit dependence of random blood samples from different diseases (cerebral and coronary vascular and myocardial disorders) were investigated. A statistical analysis showed the assumption as invalid. Therefore, it will be recommended to evaluate pathological blood samples at the measured hematocrit.  相似文献   

17.
The development of a cell-culture system for the cloning and clonal differentiation of different types of blood cell has made it possible to identify: (i), the proteins that regulate growth and differentiation of different cell lineages in normal and leukaemic blood cells; (ii), the molecular basis of normal and abnormal control of cell development in blood-forming tissue; and (iii), how to suppress malignancy in leukaemic cells. By using myeloid blood cells as a model system, it has been shown that normal blood cells require different proteins to induce cell viability and multiplication (growth-inducers) and differentiation (differentiation-inducers), that there is a hierarchy of growth-inducers which act at various stages of cell development, and that a growth-inducer can switch on production of a differentiation-inducer. Gene cloning has established a multigene family for these proteins. Identification of these proteins and their interaction has shown how growth and differentiation are regulated in normal development and demonstrated the mechanisms that uncouple growth and differentiation so as to produce malignant cells. Normal cells require an external source of growth-inducing protein for cell viability and multiplication. Cells can become leukaemic by genetically changing this normal requirement for growth without blocking response to normal differentiation-inducers. The mature cells induced by adding these normal protein-inducers are then no longer malignant. Other genetic changes which inhibit differentiation by the normal blood-cell regulatory proteins can occur in the evolution of leukaemia. But even these leukaemic cells may still be induced to differentiate by other compounds that can induce differentiation by alternative pathways. The differentiation of leukaemic to mature cells, which stops the cells from multiplying, results in the suppression of malignancy by bypassing genetic changes that produce the malignant phenotype. The activity of blood-cell growth- and differentiation-inducing proteins has been shown in culture and in the body. They can, therefore, be clinically useful to correct defects in the development of normal and leukaemic blood cells.  相似文献   

18.
Utrophin is the autosomal homologue of dystrophin. In normal skeletal muscle it is localised only to neuromuscular and myotendinous junctions, nerves and vascular tissue. In Xp21 muscular dystrophies, utrophin is also detected on the sarcolemma of skeletal and cardiac muscle, while dystrophin is absent or reduced. In normal cardiac muscle, some reports have demonstrated utrophin at intercalated discs and T-tubules. We have re-examined the distribution of utrophin in normal human cardiac muscle using a panel of eight monoclonal antibodies against different epitopes in N- and C-terminal domains. In contrast to previous studies, utrophin was not detected at the intercalated discs or T-tubules, although labelling of blood vessels was strong. We conclude that the primary location of utrophin in normal heart is in the vascular system. In addition, our results show that the utrophin on cardiac blood vessels is full length, similar to that of skeletal muscle blood vessels.  相似文献   

19.
We compared the luminol-dependent chemiluminescence (CL) response of peripheral blood from severely burned patients with that from normal controls to evaluate the primary defense level against bacterial infection in the patients. The CL was measured upon addition to diluted whole blood of a soluble stimulus, phorbol myristate acetate (PMA) or particulate stimuli such as bacteria or zymosan without special opsonization. In the early post-burn days, the initial rate of whole blood CL induced with the particulate stimulus was much lower than that in the normal controls, whereas the rate was higher when PMA was used as a stimulus. The number of granulocytes in the patients' blood had increased and isolated polymorphonuclear leukocytes (PMNs) from the patients exhibited higher CL responses to the particulate or soluble stimulus as compared with those of normal controls. The results suggest that the PMNs in burn patients were activated and normally mobilized in the early post-burn period but the opsonizing capacity in the blood decreased. In fact, the serum levels of complement, immunoglobulins and fibronectin were found to be lower in the blood from the patients than those from normal controls and a supplement of freshly frozen plasma of human immunoglobulin preparations restored the initial rate of the whole blood CL upon phagocytosis. The prognosis is still poor when severe infection occurs in the patients with decreased CL response of whole blood. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) enhanced the CL response of PMNs from burn patients. The administration of rhG-CSF may be useful for decreasing the morbidity of severe infection following burn injury in the near future.  相似文献   

20.
A cellular automaton model for tumour growth in inhomogeneous environment   总被引:1,自引:0,他引:1  
Most of the existing mathematical models for tumour growth and tumour-induced angiogenesis neglect blood flow. This is an important factor on which both nutrient and metabolite supply depend. In this paper we aim to address this shortcoming by developing a mathematical model which shows how blood flow and red blood cell heterogeneity influence the growth of systems of normal and cancerous cells. The model is developed in two stages. First we determine the distribution of oxygen in a native vascular network, incorporating into our model features of blood flow and vascular dynamics such as structural adaptation, complex rheology and red blood cell circulation. Once we have calculated the oxygen distribution, we then study the dynamics of a colony of normal and cancerous cells, placed in such a heterogeneous environment. During this second stage, we assume that the vascular network does not evolve and is independent of the dynamics of the surrounding tissue. The cells are considered as elements of a cellular automaton, whose evolution rules are inspired by the different behaviour of normal and cancer cells. Our aim is to show that blood flow and red blood cell heterogeneity play major roles in the development of such colonies, even when the red blood cells are flowing through the vasculature of normal, healthy tissue.  相似文献   

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