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1.
The susceptibility of two common breeds of cattle in the Pyrenees, Brown Swiss and Pyrenean breed, to parasitism by gastrointestinal nematodes was studied. Twenty-two female calves (13 Brown Swiss and 9 Pyrenean), 3 months old with a mean weight of 112.8 +/- 18.33 and 103.3 +/- 17.11 kg respectively at the start of the study, were used. The calves began their first grazing season grazing with 200 cattle following the traditional grazing system for mountainous areas: Stabling during winter (December-April), grazing on harvesting meadows at an elevation of 900 m in the spring (May-June) and autumn (October-November), and grazing areas between 1200-2100 m during the summer (July-September). Faeces, blood samples and calves growth rate were taken at 2-week intervals throughout the grazing season. Faecal egg counts of gastrointestinal nematodes, level of serum pepsinogen, total serum protein and blood parameters were measured. The worm egg counts and Cooperia sp. counts were significantly smaller in the calves of Pyrenean breed than in Brown Swiss throughout the experiment. Numbers of eggs of the other genera of parasites found were smaller in the calves of Pyrenean breed than in calves of Brown Swiss breed, but no statistical differences were found. Blood was compared during two periods: the prepatent and patent periods. During the first period, no differences were found between the breeds for any parameter studied. However, during the patent period, Pyrenean animals had significantly greater numbers of erythrocytes, haemoglobin values and packed cell volume (PCV) values, and smaller numbers of eosinophils than animals of the Brown Swiss breed. No differences were found in the level of serum pepsinogen, total serum protein and live weight gains between the two breeds.  相似文献   

2.
The effect of hemolysis on several assays performed with the Hitachi 717 was quantified by relating the amount of error to the concentration of hemoglobin. Hemolysis interference was judged clinically significant when analyte concentration varied by > 10% from the initial value. Hemolysis interference was significant for alkaline phosphatase, aspartate aminotransferase, alpha-amylase, bilirubin, creatine kinase, gamma-glutamyltransferase, lactate dehydrogenase, lactate dehydrogenase-1, potassium, and theophylline assays. Error (expressed in absolute terms) was linearly dependent on hemoglobin concentration and independent of the initial analyte concentration in each case, except for bilirubin and theophylline, where multiple regression analysis was required to quantify the effect. Relative error was dependent on the initial analyte concentration in all cases. Correction formulas were calculated from linear regression of absolute error vs hemoglobin concentration. Clinical application of correction formulas and mechanisms of hemolysis interference for each assay are discussed.  相似文献   

3.
Hemodilution with plasma expanders is a widely applied practice during extracorporeal circulation and hemodialysis. Despite the immediate beneficial effects of hemodilution, such as reduction of blood viscosity and red blood cell (RBC) aggregation, elevation of blood flow in the microcirculation, etc., the dilution of plasma may cause some unfavorable effects on RBCs, amplifying the mechanical damage caused by circulatory assist devices. The authors investigated the effect of partial and total replacement of plasma on susceptibility of human and bovine RBCs to mechanical stress in vitro. Hemolysis was measured after the exposure of RBCs suspended in different media to similar mechanical stress. Experiments were performed at room temperature with control of osmolality and viscosity of the suspension media. The lowest hemolysis was obtained for RBCs suspended in serum, plasma, and albumin solutions. Hemolysis in PBS and Dextran suspensions was more than three times higher than that in plasma (p < 0.001). The protective effect depended upon protein concentration. Human RBCs were found to be significantly more sensitive to mechanical stress than bovine RBCs in all investigated suspension media (p < 0.005). Human RBCs from men suspended in plasma were found to be significantly (p < 0.05) more fragile than RBCs from women. The presence of even small amounts of plasma (such as 25%) in the suspension media significantly (p < 0.001) decreased hemolysis. However, a 30% replacement of plasma with PBS or Dextran solutions caused a statistically significant (p < 0.001) increase in mechanical hemolysis. This suggests that a decrease in the concentration of plasma proteins due to hemodilution may elevate blood damage during extracorporeal circulation and hemodialysis.  相似文献   

4.
The heat and hemolysis around a shaft seal were investigated. Materials were original pumps (Nikkiso HMS-15:N-original, and 3M Delphin:D-original), vane-removed pumps (Nvane(-), Dvane(-)), and a small chamber with a shaft coiled by nichrome wire (mock pump). The original pumps were driven at 500 mmHg and 5 L/min, and vane-removed pumps were driven at the same rotation number. An electrical powers of 0, 0.5, 2, and 10 W was supplied to the mock pumps. In vitro hemolytic testing showed that hemolytic indices were 0.027 g/100 L in N-original, 0.013 in Nvane(-), 0.061 in D-original, and 0.012 in Dvane(-). Measurement of heat with a thermally insulated water chamber showed total heat within the pump of 8.62 and 10.85 W, and heat at the shaft seal of 0.87 and 0.62 W in the Nikkiso and Delphin pumps, respectively. Hemolysis and heat generation of mock pumps remained low. The results indicate that the heat generated around the shaft seal was minimal. Hemolysis at the shaft-seal was considerable but not major. Local heat did not affect hemolysis. It was concluded that the shaft-seal affected hemolysis, not by local heat but friction itself.  相似文献   

5.
Mean systemic pressure (MSP) and mean pulmonary pressure (MPF), which are mean driving pressures for venous return in the natural heart, were studied in 11 calves in which the natural heart had been replaced with a total artificial heart (TAH). They were measured simply by stopping the artificial heart pumping. Although blood translocation from the arterial to the venous side was not performed, the eventual right and left atrial pressures reached six to eight seconds after stopping the TAH would represent MSP and MPP with reasonable accuracy. The MSP varied from nine to 3k mmHg (20+/-6 mmHg), whereas the MPP varied from nine to 39 mmHg (22+/-7 mmHg). The MSP varied in close relation to the right atrial pressure prior to cessation of the TAH (r=0.9124). Increases in RAP and MSP were mainly attributed to an increase in circulating blood volume. In the performance of the TAH, MSP (or MPP), proper diastolic duration and vacuum application during diastole was of prime importance in determining the end-diastolic ventricular volume.  相似文献   

6.
Although the use of sheep in total artificial heart (TAH) implantation has many advantages, they are known to show a significant morbidity rate on cardiopulmonary bypass (CPB); this has been considered to be a major limiting factor in using them for TAH experiments. We conducted a series of ovine CPB experiments to evaluate the sheep's pathophysiological response to CPB. CPB-related hemolysis, bleeding, and lung dysfunction were analyzed in 5 sheep, which had undergone CPB, used at our hospital for TAH implantation. Four of the 5 sheep survived the experimental procedures, and 3 of them survived on a long-term basis. Unacceptable degrees of hemolysis related to CPB were not observed. Postoperative bleeding was not remarkable, and coagulation test results did not show significant abnormal findings. Acute lung injuries of a mild to moderate degree were found mainly at the microscopic level, but rarely had clinical significance. In conclusion, this experiment suggests that sheep can be used for the animal model for TAH implantation with acceptable risk on CPB circuits and techniques are used.  相似文献   

7.
Hemolysis due to donor-derived antibodies produced by "passenger" B lymphocytes, called passenger lymphocyte syndrome, has been described in ABO-unmatched solid organ and bone marrow transplant recipients. Delayed hemolytic transfusion reactions occur within a similar time frame and have similar clinical and serologic findings. To our knowledge, we report the first case of hemolysis due to the simultaneous occurrence of passenger lymphocyte syndrome (donor-derived anti-A) and a delayed hemolytic transfusion reaction (recipient-produced anti-E) in a liver transplant patient.  相似文献   

8.
9.
We recently proposed a new concept, the total destruction time of erythrocytes, to indicate sublethal damage to erythrocytes by blood pumps. In this article, results of additional experiments concerning this new concept are reported. Five paired in vitro hemolysis tests with bovine blood were conducted using a cone-type centrifugal pump (Group A) and an impeller-type pump (Group B). A total pressure head of 100 mm Hg was applied. The factors evaluated were the normalized index of hemolysis and the total destruction time, or the pumping duration, required to raise the level of the plasma-free hemoglobin to 50% of the total hemoglobin. The morphologic change of the erythrocytes also was analyzed. The percentage of crenated cells was calculated from blood smear specimens 1 min after starting the pumps and 2 h before the total destruction time of Group A in each experiment. Although there was no statistical difference in the normalized index of hemolysis between the two groups, the total destruction time of Group A erythrocytes was significantly shorter than that of Group B (18.9 +/- 4.5 h and 33.7 +/- 9.9 h in Group A and Group B, respectively; p < 0.02). The rate of crenated erythrocytes was higher in Group A than in Group B at a point 2 h before the total destruction time of Group A. The total destruction time values seem to define a good method for establishing sublethal traumatic damage to erythrocytes in blood pumps.  相似文献   

10.
Rats were flown aboard the Soviet biosatellite Cosmos 936 for 18.5 d during August, 1977. Five rats were subjected to near-weightless space flight, as with Cosmos 782, and five rats were subjected to a 1-G force via an on-board centrifuge. These rats and three control groups were injected with 2-14C glycine 19 d preflight. The flight rats were recovered from orbit after 18.5 d of space flight. Erythrocyte hemolysis and lifespan were evaluated in the five groups of rats by quantitation of radioactive carbon monoxide exhaled in the breath which arises from the breakdown of the previously labeled hemoglobin. The results support our previous findings wherein hemolysis was found to increase as a result of weightless space flight. A comparison to the centrifuged animals indicates that artificial gravity attenuates the effect of weightlessness on hemolysis and appears to normalize the hemolytic rate in the early postflight period.  相似文献   

11.
A cooperative effort between Baylor College of Medicine and NASA/Johnson Space Center is under way to develop an implantable left ventricular assist device for either pulmonary or systemic circulatory support for more than 3 months' duration. Using methodical evaluation and testing, an implantable axial pump has been systematically improved. These improvements include the addition of an inducer as a pumping element in front of the impeller and the construction of an efficient brushless direct current motor. To date, less than 10 W of power is required to generate 5 L/min flow against 100 mm Hg. An index of hemolysis of 0.021 g/100 L has been achieved. Two-day in vivo feasibility studies in calves are under way to evaluate the antithrombogenic nature of the pump. Further improvements in system efficiency, hemolytic performance, and the antithrombogenic nature of the pump are expected with the use of empirical studies, computer flow modeling, and in vivo testing in calves.  相似文献   

12.
INTRODUCTION: Hemolysis and red cell fragmentation accompanying vitamin B12 deficiency may misdirect the diagnosis. Signs of malabsorption and abnormalities related to folic acid metabolism characterized by discrepancies between folic acid normal serum levels and erythrocytic folic acid levels may also exist. EXEGESIS: We report the occurrence of hemolysis and red cell fragmentation mimicking microangiopathic hemolytic anemia, malabsorption and folic acid deficiency in the course of vitamin B12 deficiency. Appropriate replacement therapy corrected all abnormalities. CONCLUSION: An association between hemolysis, malabsorption and folic acid deficiency should lead physicians to search for signs of vitamin B12 deficiency.  相似文献   

13.
The presence in serum of adenylate kinase isoenzyme originating from erythrocyte can be useful as a marker for detecting hemolysis. We have presented preliminary evidence for identifying hemolytic anemia patients earlier by determining erythrocyte AK isoenzyme activity in serum (or plasma) rather than using measurement of plasma hemoglobin concentration. This test being quite specific for hemolysis should find use as a quick method for estimating the extent of in vivo hemolysis in hemolytic patients earlier than heretofore possible.  相似文献   

14.
Because of severe hemolysis, especially on producing pulsatile flow by changing the rotating speed of the impellers, the traditional centrifugal pump was rarely used for long-term support of the failing heart. We therefore developed a motor driven pulsatile implantable impeller pump. The pulsatility was achieved by changing the rotating speed via introducing a square waveform voltage into the motor coil. The impeller vane was designed to have both radial and axial curves according to the stream surface and stream lines to reduce the thrombosis and hemolysis. Nine calves weighing 80 to 100 kg were used. With the calves under endotracheal general anesthesia, left posterolateral thoracotomy was performed to connect the inflow tube with the left atrial appendage and to anastomose the outflow tube with the descending aorta. The calves usually awoke and stood up within hours after discontinuation of anesthetics. Within 7 days, continuous monitoring of electrocardiogram, systemic and pulmonary arterial pressures, and central venous pressure were performed to adjust the pump flow to 40% to 50% of the cardiac output. During the survival of 4 to 54 days (mean 16.3 +/- 19.3 days with two calves surviving longer than 1 month), no significant deterioration of liver or renal function was noted. Because of bleeding, hemoglobin reduced from 11.4 +/- 1.8 to 9.0 +/- 1.3 g/dl, and the hematocrit decreased from 34.5 +/- 4.7 to 26.7 +/- 4.6%. No significant changes of free hemoglobin were noted. In our results, the device revealed competent pulsatile function without severe blood damage or organ dysfunction.  相似文献   

15.
BACKGROUND: Although red cell (RBC) antibodies of the Dombrock blood group system have been reported to cause acute and delayed hemolytic transfusion reactions, the difficulty in identifying these antibodies in patients with multiple RBC alloantibodies has not previously been discussed. The cases of four sickle cell disease patients who developed Dombrock system antibodies after transfusion, three of which were discovered in association with hemolytic transfusion reactions, are reported. CASE REPORTS: Patient 1 was a 36-year-old woman with multiple RBC alloantibodies. Because of the lack of an increment in hematocrit after transfusion, an investigation was performed; it revealed anti-Do(b) in the serum. Patient 2 was a 30-year-old woman with known anti-C, -E, -K, -S, -Fya, and -Bga. She had received a transfusion 10 days previously. Before further transfusion was begun, antibody identification revealed weak nonspecific reactions, which were thought to be HLA antibodies. She developed acute hemolysis during RBC exchange for acute chest syndrome; anti-Doa was identified in both the serum and eluate. She received 2 units of Do(a-) RBCs without complication. Patient 3 was a 35-year-old woman with known anti-C, -E, -K, -Fya, and -N and a warm autoantibody. Two weeks after transfusion, she had a delayed hemolytic transfusion reaction coincident with the identification of anti-Doa. Patient 4 was a 33-year-old woman with known anti-C, -V, -K, -Fya, -Fy3, Jkb, -S, -N, and -Ytb, who developed anti-Doa 8 weeks after transfusion. CONCLUSION: An association of Dombrock blood group system antibodies with hemolytic reactions is demonstrated in alloimmunized sickle cell disease patients. In all four cases, identification of Dombrock system antibodies was delayed because high-titer low-avidity antibodies, HLA antibodies, or autoantibodies were thought to explain the serologic findings. The presence of Dombrock system antibodies should be considered when unexplained serologic reactivity occurs during antibody identification in this population.  相似文献   

16.
The literature indicates that sire breed of calf influences beef calf performance. However, there is little information concerning sire breed of calf effects on reproduction in beef cows. In this experiment, Angus (A), Brahman (B), or Tuli (T) bulls were bred to 136 Brahman (B) cows to examine sire breed of calf influence on peripartum hormone profiles and the length of postpartum anestrus. Cows were bled from 7 d prepartum to 28 d postpartum to determine peripartum hormone concentrations. Cows carrying AB calves had greater (P < 0.05) prepartum estradiol-17 beta concentrations than did cows carrying BB and TB calves. Prepartum and postpartum progesterone concentrations did not differ between cows with AB, BB, and TB calves. Cows with TB calves had lower (P < 0.01) 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) concentrations than did cows with AB and BB calves during the early postpartum period. Adjusting for birth weight removed the sire breed of calf effect on postpartum PGFM concentrations, but not prepartum estradiol-17 beta. Postpartum anestrus was shorter (P < 0.05) for cows nursing BB calves (84 +/- 6 d) than for cows nursing AB (101 +/- 6 d) or TB calves (110 +/- 7 d). Adjustment for estradiol or PGFM concentrations did not reduce sire breed of calf effects on the length of postpartum anestrus. Further work is heeded to determine how calf genotype may modulate the postpartum reproductive function of the dam.  相似文献   

17.
The objective of the present paper was to examine the development of the total protein concentration in blood serum and the gamma-GT activity in 49 calves in relation to the health status during the first 14 days of life. For this purpose, blood samples were taken immediately after birth of the animals, after 6, 12, 18 and 24 hours and from then onwards once a day with the calves being subject to a thorough clinical examination each time. All calves received pooled colostrum. At the end of the experiment, the calves were subdivided into three groups on the basis of their health status, i.e. control calves, calves with a slight or moderately severe disease and calves suffering from a severe disease. In all three groups the total protein concentration increased significantly after the colostrum intake and decreased slowly from the 2nd day of life onwards. The gamma-GT activity as well increased significantly after the colostrum intake and decreased rapidly after 12th hour of life and progressively in the further course of the experiment. Both parameters varied considerably from one calf to the next and no statistically significant differences in these parameters between the three groups could be found. It can thus be deduced that the total protein concentration in blood serum and the gamma-GT activity do not allow any predictions about the development of the health status during the first 14 days of life to be made.  相似文献   

18.
A severe hemolytic crisis was observed in a 34-yr-old female of English-Irish extraction following a viral illness treated with acetaminophen. Heinz bodies and heat instability were present only during a transient hemolytic event. A challenge dose of acetaminophen caused no detectable hematologic abnormality. Structural studies of the hemoglobin during hemolysis and again after complete recovery localized the abnormality to tryptic peptide beta Tp-5, and automated sequencing of I 125-labeled beta chains indicated a replacement of phenylalanine (C7) beta 41 by tyrosine. Substitution of the next residue, phenylalanine (CD1) beta 42 by serine (Hb Hammersmith), has resulted in chronic severe Heinz body hemolytic anemia. The lack of chronic anemia in the present disorder may reflect the different relationships of beta41 and beta 42 and/or the similarities in volume and hydrophobicity of tyrosine and phenylalanine. It is suggested that substitution of tyrosine for phenylalanine in Hb Mequon may disturb the critical environment around the heme group and render it susceptible to oxidative denaturation in the presence of infections and/or drugs.  相似文献   

19.
Hemolysis and resistance of erythrocytes were studies in-vitro in experiments on human ACD fresh blood and on heparinized fresh blood after oxygen dispersion, resp. mixed oxygen and carbon dioxide dispersion, and subsequent treatment in the hemoresistometer. Blood alkalinity increases under oxygen dispersion, acidity increases under dispersion with mixed gases. The length of the period of dispersion is more important for hemolysis than the change of pH. The hematocrit value influences the behavior of blood resistance. High values imply enhanced hemolysis. There is no significant difference of actual hemolysis values between oxygen and oxygen/carbon dioxide dispersion. A different behavior appears in the calculation of difference value of hemolysis after treatment in resistometer and the respective actual hemolysis.  相似文献   

20.
A group of 1,052 C578L/6J mice -- 296 males and 756 females - was kept under well defined, clean, conventional conditions from the age of 6 weeks until natural death. At regular time intervals several hematological values were examined from 50 to 60 randomly selected animals of each sex and statistically evaluated. The hematological investigations did not reveal any important sex-related differences. A significant gradual decrease of the RBC counts and hemoglobin content was observed during the life-span. Lymphocyte and total WBC counts were subject to considerable variation. They decreased in the first two-thirds of life and increased in the last third. Neutrophils remained rather stable and exhibited an increasing trend in the higher age. The relative level of lymphocytes decreased signficantly in favour of neutrophils during natural aging.  相似文献   

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