mechanisms to integration( Volume 2). Berlin: Springer 7.吴祖泽、贺福初、裴雪涛主编.2000.造血调控.上海:上海医科大学出版社 8.李勇、杨贵贞主编.1999人类红细胞血型学实用理论与实验技术.北京:中国科学技术 出版社 9. Humeau L, Bardin F, Maroc C, et al. 1996. Phenotypic, molecular, and functional characterization of human peripheral blood, CD34+/Thy 1+ cells. Blood, 87(3) 949-55 10. Zanjiani ED, Almeida-Porada G, Livingston AG, et al. 1998. Human bone marrow CD34- cells engraft in vivo and undergo multilineage expression that includes giving rise to CD34+ cells Exp Hematol, 26(4) 353-60 11. Thompson JA, Gilliland DG, Prchal JT, et al. 2000. Effect of recombinant human erythropoietin combined with granulocyte/macrophage colony stimulating factor in the treatment of patients with myelodysplastic symdrome. Blood, 95(4): 1175-9 12. Ding L, Lu S, Batchu R, et al. 1999. Bone marrow stromal cells as a vehicle for gene transfer Gene ther,6(9):1611-6 13. Rosenson RS, MoCormick A, Uretz EF. 1996. Distribution of blood viscosity values and biochemical correlates in healthy adults. Clin Chem, 42(8 Pt 1): 1189-95 14. Yuang S, Law P, Young D, et al. 1998. Candidate hematopoietic stem cells from fetal tissues umbilical cord blood vS. adult bone marrow and mobilized peripheral blood. Exp Hematol,26(12)1162-71 5. Berardi AC, Wang A, Levine JD, et al. 1995. Functional isolation and characterization of human hematopoietic stem cells. Science, 267 (5194): 104-8 6. Kaushansky K. 2003.Thrombopoietin accumulating evidence for an important biological effect on the hematopoietic stem cell. AnnN Y Acad Sci, 996: 39-43 ummary Blood is composed of blood cells and plasma. The blood cells comprise red blood cells (erythrocytes), white blood cells (leukocytes), and the platelets(thrombocytes). Blood cells perform a variety of functions, including delivery of oxygen by red blood cell, formation of blood clots by platelet, host defense against infectious organisms by monocyte or granulocyte, and immune regulation by lymphocyte. The hematocrit is defined as the percentage of blood volume that is occupied by blood cells. The plasma, the liquid portion of the blood, consists of a large number of organic and inorganic substances dissolved in water, which can be expressed by the osmotic pressure(crystalloid substance for crystalloid osmotic pressure and plasma protein for colloid osmotic pressure). The functions of blood are transport, buffer function, regulation of body temperature, physiological hemostasis and protection against foreign substances and organisms Hematopoietic stem cells develop into committed progenitor cells called colony forming units, which generate colonies of specific blood cell type The mature red blood cell is a non-nucleated. round biconcave discs having a mean diameter of about 7. 8 micrometers. with a average concentration of 4-6x10/L for human beings. The physiological characteristics of erythrocytes include membrane permeability, plastical deformability, suspension stability, and osmotic fragility. The functions of erythrocytes are the carriage of oxygen and carbon dioxide and the buffering of pH. Production of normal erythrocytes requires protein, iron, folic acid, and vitamin B12 The blood of a healthy person contains 4.0-10x10/L leukocytes. The leukocytes are not amechanisms to integration(Volume 2).Berlin:Springer. 7. 吴祖泽、贺福初、裴雪涛主编. 2000. 造血调控. 上海：上海医科大学出版社. 8. 李勇、杨贵贞主编. 1999. 人类红细胞血型学实用理论与实验技术. 北京：中国科学技术 出版社. 9. Humeau L, Bardin F, Maroc C, et al. 1996. Phenotypic,molecular,and functional characterization of human peripheral blood, CD34+/Thy1+ cells. Blood, 87(3):949-55. 10. Zanjiani ED, Almeida-Porada G, Livingston AG, et al. 1998. Human bone marrow CD34- cells engraft in vivo and undergo multilineage expression that includes giving rise to CD34+ cells. Exp Hematol,26(4):353-60. 11. Thompson JA, Gilliland DG, Prchal JT, et al. 2000. Effect of recombinant human erythropoietin combined with granulocyte/macrophage colony stimulating factor in the treatment of patients with myelodysplastic symdrome. Blood,95(4): 1175-9. 12. Ding L, Lu S, Batchu R, et al. 1999. Bone marrow stromal cells as a vehicle for gene transfer. Gene Ther, 6(9):1611-6. 13. Rosenson RS, MoCormick A, Uretz EF. 1996. Distribution of blood viscosity values and biochemical correlates in healthy adults. Clin Chem,42(8 Pt 1):1189-95. 14. Yuang S, Law P, Young D, et al. 1998. Candidate hematopoietic stem cells from fetal tissues, umbilical cord blood vs. adult bone marrow and mobilized peripheral blood. Exp Hematol,26(12):1162-71. 15. Berardi AC, Wang A, Levine JD, et al. 1995. Functional isolation and characterization of human hematopoietic stem cells. Science,267(5194):104-8. 16. Kaushansky K. 2003.Thrombopoietin:accumulating evidence for an important biological effect on the hematopoietic stem cell. Ann N Y Acad Sci,996:39-43. Summary Blood is composed of blood cells and plasma. The blood cells comprise red blood cells (erythrocytes) , white blood cells (leukocytes), and the platelets (thrombocytes). Blood cells perform a variety of functions, including delivery of oxygen by red blood cell, formation of blood clots by platelet, host defense against infectious organisms by monocyte or granulocyte, and immune regulation by lymphocyte. The hematocrit is defined as the percentage of blood volume that is occupied by blood cells. The plasma, the liquid portion of the blood, consists of a large number of organic and inorganic substances dissolved in water, which can be expressed by the osmotic pressure (crystalloid substance for crystalloid osmotic pressure and plasma protein for colloid osmotic pressure). The functions of blood are transport, buffer function, regulation of body temperature, physiological hoemostasis and protection against foreign substances and organisms. Hematopoietic stem cells develop into committed progenitor cells called colony forming units, which generate colonies of specific blood cell type. The mature red blood cell is a non-nucleated, round biconcave discs having a mean diameter of about 7.8 micrometers, with a average concentration of 4-6×1012/L for human beings. The physiological characteristics of erythrocytes include membrane permeability, plastical deformability, suspension stability, and osmotic fragility. The functions of erythrocytes are the carriage of oxygen and carbon dioxide and the buffering of pH. Production of normal erythrocytes requires protein, iron, folic acid, and vitamin B12. The blood of a healthy person contains 4.0~l0×109 /L leukocytes. The leukocytes are not a 11