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1.
1. The Bohr effects of trout blood (which exhibits the Root effect) and of human blood were compared. Precise oxygen equilibria were measured with an automatic recording system, on normal trout red blood cell suspensions at pH 7.6 - 8.6, at 10 and 20 degrees C, and on normal human red blood cell suspensions at pH 6.8 - 8.0, at 37 degrees C. 2. The data were fitted to the Adair's stepwise oxygenation model which describes experimental curves with four constants ki (i = 1-4). 3. Adair's scheme successfully fits the equilibrium data for trout and human blood, in the range of conditions examined. 4. The R-state Bohr effect (d log k4/ d pH), is very large in trout blood, indicating a large pH dependence of the R structure, as opposed to human blood. 5. The T-state Bohr effect (d log k1/ d pH), and the overall Bohr effect (d log Pm/ d pH), are equivalent in trout and human blood. 6. The overall Bohr effect is essentially accounted for by the first and fourth oxygenation steps in trout blood and shows a significant effect of temperature. 7. The data attribute a major role to Hb4 in trout blood isotherms and confirm the importance of the C-termini of Beta chains in Bohr and Root effects.  相似文献   

2.
The hemolytic effect of glyceryl guiacolate ether (GGF) with and without chloromazine (CPZ) was studied in vitro on rat, dog and human blood. The lowest concentration of GGE which could produce hemolysis of rat red cells was 0.15 M. The time fpr 50% hemolysis (TH50) of blood depended upon the concentration of drug and dilution of blood. A higher concentration of GGE hemolyzed blood much faster than the lower. There was a progressive increase in the TH50 when 0.15 M GGF was tested on blood samples containing increasing numbers of red cells. CPZ in all cases had its own hemolytic effect at higher concentrations. In this regard rat blood was 10 times more sensitive than dog, and human. A striking potentiating effect of CPZ was observed on the hemolytic effect of GGE. The magnitude of potentiation in all cases was directly related to the concentrations of CPZ. Dog blood was found relatively more sensitive to the hemolytic effect of the combination of CPZ and GGE as compared to the rat and human, which acted alike.  相似文献   

3.
Intraperitoneal administration of the PGP did not change basal mucosal blood flow, whereas the PG and GP significantly decreased it. Ethanol and Indomethacin caused a rapid and stable decrease in the blood flow. Administration of the PGP prior to ethanol abolished this effect. Injections of the PGP and PG following Indomethacin administration prevented reduction of the mucosal blood flow. Administration of the GP did not change the blood flow decrease induced with Indomethacin. The mucosal blood flow correction seems to be one of the possible mechanisms of the PGP and PG antiulcer effect. The effect seems to be realised through a change in the CNS activity.  相似文献   

4.
Data from 13 randomised trials on the effect of sodium restriction on blood pressure were analysed. The hypotensive effect of sodium restriction was found to be small and restricted largely to systolic blood pressure, which fell by an average of 3.6 mm Hg (range 0.5-10.0 mm Hg). The reduction increased with age and in those with higher blood pressure. Sodium restriction therefore seems to be of limited use in those who are most eligible for non-pharmacological treatment of high blood pressure--namely, young patients with mild hypertension.  相似文献   

5.
The Bohr effect was measured in normal whole blood and in blood with low DPG concentration as a function of oxygen saturation. pH was changed by varying CO2 concentration (CO2 Bohr effect) or by addition of isotonic NaOH or HC1 at constant PCO2 (fixed acid Bohr effect). At nornal DPG concentration CO2 Bohr effect was -0.52 at 50% blood oxygen saturation, increasing in magnitude at lower saturation and decreasing in magnitude at higher saturation. In DPG depleted blood with base excess (BE) similar to 0 meq/1, there was similar dependence of CO2 Bohr effect on oxygen saturation. At BE similar to -10 meq/1, influence of saturation was comparable, but the magnitude of the Bohr effect was markedly increased at all saturations. Fixed acid Bohr effect at normal DPG concentration was -0.45 at saturations of 50-90% but decreased at lower saturations. In DPG-depleted blood fixed acid Bohr effect averaged about -0.33 with minimal variation with saturation. Influence of DPG on oxygen affinity was greater at intermediate saturations and less at saturations below 20% and above 80%. Effect of CO2, independent of pH, was many fold greater at lower oxygen saturations than at higher saturations. These results support the suggestion that the alpha chain of hemoglobin is the site of the initial oxygenation reaction. Physiologically they indicate that the relative contribution of CO2 and fixed acid, as well as the level of oxygen saturation and DPG concentration, may be important in determining PO2 of capillary blood and resulting oxygen delivery.  相似文献   

6.
韦继政  黄远昌 《蛇志》1998,10(4):10-11
目的观察东菱精纯克栓酶对高粘血症患者血液流变学的影响,并探讨其影响机制。方法用东菱精纯克栓酶治疗28例高粘血症患者。结果东菱精纯克栓酶能明显地降低血粘度,表现为全血粘度、血浆比粘度、全血还原粘度及纤维蛋白原水平降低。结论东菱精纯克栓酶通过降低高粘血症患者血粘度而起治疗作用。  相似文献   

7.
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   

8.
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   

9.
目的探讨营养,年龄及性别等因子对Ⅱ型糖尿病动物模型-KK/Upj-A^y/J小鼠血糖的影响。方法尾部取血,用血糖仪测定实验组和对照组动物的血糖并进行实验分析。结果实验组血糖值明显高于对照组;实验组发病动物的比例也明显高于对照组动物;对照组8月龄小鼠血糖值低于糖尿病的发病标准;实验组年龄对动物的血糖影响较小;实验组和对照组性别基本不影响动物的血糖。结论(1)在同样携带A^y黄色肥胖糖尿病基因的遗传作用的条件下,饲料中的营养成分是影响小鼠血糖的主要因素,(2)动物的年龄是影响血糖的另一主要因素。(3)性别对动物血糖的影响不大。  相似文献   

10.
An effect of the treatment with guanfacine on the activity of the adreno-sympathetic system, beta-thromboglobulin, beta-endorphin, and blood lipids was studied in 30 patients with the primary arterial blood hypertension. It was found that guanfacine significantly decreases plasma noradrenaline, adrenaline, and dopamine. Moreover, it decreases the excretion of noradrenaline, adrenaline and 4-hydroxy-3-methoxy-phenylglycol. These effects correlate with the drop in both systolic and diastolic blood pressure. A decrease in plasma renin activity was also observed. It correlated with the blood pressure drops. Guanfacine increased beta-endorphin levels while beta-thromboglobulin, total cholesterol and triglycerides levels remained unaffected. The authors suggest that the hypotensive effect of guanfacine is related to the decrease in adreno-sympathetic system activity and plasma renin activity and no effect on the erythrocyte activity and lipids metabolism.  相似文献   

11.
The effects of D- and L-isoprenaline on systemic vascular adrenoceptors of the cod was studied using blood pressure recording from conscious cod in vivo and isolated coeliac artery strip preparations in vitro. Experiments with isolated artery preparations demonstrated that the D-, but not the L-isomer of isoprenaline acts as an alpha-adrenoceptor antagonist. A dose-dependent reduction of ventral and dorsal aortic blood pressures together with a dose-dependent increase in the heart rate could be produced by injection of L-isoprenaline. D-Isoprenaline, on the other hand, had no effect on the blood pressures or heart rate except in the highest dose injected. The results show an alpha-adrenoceptor blocking capacity of D-isoprenaline in the cod. The effect of L-isoprenaline on the blood pressure supports the idea that the hypotensive effect of DL-isoprenaline seen in previous studies of the cod may be attributed to an effect of the L-isomer on beta-adrenoceptors mediating vasodilation of the cod systemic vasculature.  相似文献   

12.
Das B  Johnson PC  Popel AS 《Biorheology》2000,37(3):239-258
The study of the effect of leukocyte adhesion on blood flow in small vessels is of primary interest to understand the resistance changes in venular microcirculation. Available computational fluid dynamic studies provide information on the effect of leukocyte adhesion when blood is considered as a homogeneous Newtonian fluid. In the present work we aim to understand the effect of leukocyte adhesion on the non-Newtonian Casson fluid flow of blood in small venules; the Casson model represents the effect of red blood cell aggregation. In our model the blood vessel is considered as a circular cylinder and the leukocyte is considered as a truncated spherical protrusion in the inner side of the blood vessel. The cases of single leukocyte adhesion and leukocyte pairs in positions aligned along the same side, and opposite sides of the vessel wall are considered. The Casson fluid parameters are chosen for cat blood and human blood and comparisons are made for the effects of leukocyte adhesion in both species. Numerical simulations demonstrated that for a Casson fluid with hematocrit of 0.4 and flow rate Q = 0.072 nl/s, a single leukocyte increases flow resistance by 5% in a 32 microns diameter and 100 microns long vessel. For a smaller vessel of 18 microns, the flow resistance increases by 15%.  相似文献   

13.
血虚证动物模型的标准化研究初探   总被引:1,自引:0,他引:1  
杨岚  祝彼得  彭成 《四川动物》2006,25(1):160-164
目的:建立标准化的血虚证动物模型。方法:采用慢性失血法、溶血法和骨髓抑制法制造三种血虚证模型,观察一般情况和与血发生有关的实验室指标,并用四物汤反证造摸效果。结果:三种动物模型均符合血虚证表现,同时出现外周血、骨髓有核细胞数目和细胞周期的改变,四物汤对3种动物模型均有一定疗效。结论:建立了3种符合标准化的血虚证模型。  相似文献   

14.
Under physiologic conditions, low concentrations of blood may be present in the uterine fluid of the estrous cow at the moment of insemination. To decrease the insemination dose and to obtain good insemination results with less fertile semen, more invasive insemination methods such as utero tubal junction (UTJ) insemination can be used. More invasive insemination methods increase the risk of damaging the hyperemic endometrium, with blood in the uterine fluid as result. In this study, the effect of 0, 0.15 and 1.5% whole blood and serum on bovine sperm quality and in vitro fertilizing capacity was evaluated. Sperm quality as assessed by total motility, progressive motility, membrane integrity and acrosomal status was not affected by the presence of blood or serum (P > 0.05). However, the in vitro fertilizing capacity decreased with increasing concentrations of blood and serum (P < 0.01). The rate of polyspermy increased with increasing concentrations of serum (P < 0.01), but not with increasing concentrations of blood (P = 0.30). In conclusion, no immediate effect of blood and serum was visible on several sperm quality parameters, except for an increased prevalence of head to head agglutination (HHA). However, blood and serum did have a negative effect on in vitro fertilizing capacity.  相似文献   

15.
The effect of methylprednisolone treatment on skin-flap viability and capillary blood flow was studied in a series of four experiments. Intramuscular methylprednisolone injections (30 mg/kg per day), given in single or divided doses preoperatively or postoperatively, had no effect in augmenting skin viability in arterialized cutaneous, myocutaneous, or random skin flaps compared with the control. Capillary blood flow was studied in arterial buttock flaps and latissimus dorsi myocutaneous flaps raised on animals treated preoperatively with methylprednisolone or saline (control), and no significant difference in capillary blood flow was noted between the treatment and control flaps. It was concluded that methylprednisolone has no significant therapeutic effect either in increasing flap viability or in increasing capillary blood flow in skin flaps in pigs.  相似文献   

16.
Tsi D  Tan A 《Bioinformation》2008,2(6):249-252
Several studies have demonstrated a link between blood viscosity and various forms of liver dysfunction. Therefore, we investigated the effect of liver protective herbal materials, Sesamin combined with extract of Schisandra chinensis berry (Schisandra) for its potential to improve blood fluidity in humans. Ten human subjects were recruited to study the effect of sesamin combined with schisandra extract (SCH) for two weeks on blood viscosity. Blood fluidity was measured as the transit time for 100mul of heparinized whole blood to pass through a micro-channel array setup at baseline, 1 week and 2 weeks. For safety assessment, blood biochemistry, hematology and urine analysis were taken at baseline, 1 week and 2 weeks after SCH administration. No safety concern and adverse effects were observed during the 2-week continuous intake period. Intake of SCH reduced blood passage time by 9.0% and 9.7% at 1 and 2 weeks, respectively. In conclusion, this pilot clinical study indicates that the combined administration of sesamin with schisandra extract could improve blood fluidity after 1 week of oral intake and this effect was sustained up to 2 weeks.  相似文献   

17.
Background:  In medicine, there is limited knowledge on the toxicity of nanoparticles. In medicine, there has been limited knowledge on the effect of nanoparticles on the white blood cell.
Objective:  To evaluate the effect of gold nanoparticle on the microscopic morphology of white blood cell.
Setting:  Chulalongkorn Univesity, Bangkok, Thailand.
Method:  This study was performed as an experimental study. Mixture of gold nanoparticle solution and blood sample was prepared and analysed.
Result:  This work revealed that after mixing the blood sample with gold nanoparticle solution, accumulation of gold nanoparticle in the white blood cell was observed.
Conclusion:  The effect of gold nanoparticle on the white blood cell can be detected and this knowledge can be used in cytotoxic drug treatment.  相似文献   

18.
The effect of gamma-amino butyric acid (GABA)-enriched soybean on blood pressure was investigated in male spontaneously hypertensive rats. Ten-week-old rats were given diets containing graded levels of GABA-enriched soybean powder for 8 weeks. The systolic blood pressure in rats fed 0.15% GABA diet was significantly lower at 1st week and maintained lower values for 4 weeks as compared with 0% GABA controls. No effect on blood pressure was found in those of 0.03 and 0.3% GABA. The results suggest that there exist appropriate dietary GABA level to get the blood pressure lowering effect.  相似文献   

19.
随着人们对于肠道菌群种类以及作用认识的逐渐深入,我们发现作为人体庞大而又复杂的微生态系统,肠道菌群的结构及和菌群分布有紧密联系的肠屏障功能的改变与人体的健康息息相关。中药作为传统医学的一种治疗方法,其对人体的治疗作用是十分显著的,而活血化瘀法是使用具有消散作用及攻逐体内淤血作用的药物来治疗人类各种疾病的一种方法,这种方法对于肠道菌群以及肠屏障功能也产生了深远的影响。本文围绕肠道菌群结构改变及肠黏膜屏障功能的变化,对近十年关于肠道菌群与活血化瘀方药的相关文献进行综述,探究活血化瘀法(中药及中药复方)对于肠道菌群的影响,为临床治疗提供新思路。  相似文献   

20.
弱激光的生物学效应及对红细胞变形性的改善作用   总被引:10,自引:0,他引:10  
简要叙述激光生物效应和弱激光生物刺激作用。概括阐述激光照射血液所产生的生物学效应,叙述了弱激光对红细胞变形性的改善作用并探讨其可能的作用机理。  相似文献   

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