Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spec...Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spectrophotometric method. The results show that the complexing properties of the ligands in comparison with those of DTPA are affected by converting two carboxyl groups to amide groups. The relaxation studies have shown that the relaxivity of the chelates is similar to that of Gd DTPA, indicating that in solution all the chelates have one water molecule directly coordinated to the metal ion. Only one water molecule in inner coordination sphere suggests the coordination of the carboxamide oxygen to gadolinium ion, which agrees with the FT IR results.展开更多
The immunostimulatory property of a synthetic polyphosphoramidate based on stearyl tyrosine (PPST) is described. The immunostimulatory activity of this negatively charged polymer was investigated in vitro through ...The immunostimulatory property of a synthetic polyphosphoramidate based on stearyl tyrosine (PPST) is described. The immunostimulatory activity of this negatively charged polymer was investigated in vitro through examining the effect on the mitogen induced lymphocytes proliferation by a tetrazolium based colormetric assay and also through studying the primary plaque forming cells (IgM PFC) responses of Balb/c mice after the intraperitoneal (i.p.) injection of the polymer with sheep red blood cells (SRBC). PPST exhibits specific and high immunostimulatory activity in vitro by the stimulation on lipopolysaccharide(LPS) induced murine B cells proliferation, which is probably due to the interaction between the polymer with LPS responding B lymphocytes. This polymer also makes a significant increase of single antibody producing cells. The result shows that the stimulation rate to IgM PFC responses of Balb/c mice achieved 77.9% ( p <0.01) when 160 mg/kg of PPST was injected 4 h before with SRBC.展开更多
THE CURRENT SITUATIONBefore the founding of the People’s Republic of China in 1949. China’s higher medical education was very backward. In the 20 years before 1949. graduates from institutions of higher medical educ...THE CURRENT SITUATIONBefore the founding of the People’s Republic of China in 1949. China’s higher medical education was very backward. In the 20 years before 1949. graduates from institutions of higher medical education totalled less than 10 000. In 1949. there were only 44 medical and pharmaceutical schools with 18 800 undergraduates. The higher medical education has taken a tortuous course of development after the founding of the People’s Republic of China. The first phase (1949-1965) was a period of prelimi-nary formation of medical education system of new China. During this period, the experience of the former Soviet Union was followed in determining the objectives of higher medical education, the length of the curriculum, specialties, the structure of the curriculum, the contents of teaching, etc. and a preliminary system was instituted. The second phase (1966-1976) was a time of chaos during which the normal educational program was disrupted. The third phase started in 1977. The wrong line was re展开更多
DTPA was covalently conjugated to the copolymer of L lysine and L tyrosine, then transchelated with Gd EDTA,the resultant polymer chelates were further reacted with 6 O bromoacetyl D galacto...DTPA was covalently conjugated to the copolymer of L lysine and L tyrosine, then transchelated with Gd EDTA,the resultant polymer chelates were further reacted with 6 O bromoacetyl D galactose or methyl lactobionyloxyacetate to give PLT(Gd DTPA) with galactose moiety as liver targeting group.These macromolecular MRI contrast agents were characterized by means of FT IR, ICP AES, elementary analyses and UV Vis spectrophotometry. Their in vitro relaxivity and liver targeting property in mice were also investigated.展开更多
A block copolymer composed of hydrophilic and crystallinic polyethylene oxide and hydrophobic and non-crystallinic polymethyl methacrylate (PMMA) was prepared by sequential initiation of alkoxy-anion and charge transf...A block copolymer composed of hydrophilic and crystallinic polyethylene oxide and hydrophobic and non-crystallinic polymethyl methacrylate (PMMA) was prepared by sequential initiation of alkoxy-anion and charge transfer complex using p-aminophenol as parent compound. The structure of copolymer was characterized by GPC, IR, 1H NMR and DSC in detail. The propagation of PMMA chain is dependent on the molecular weight and concentration of the first block PEO and also the polarity of solvents. The reasons are discussed.展开更多
文摘Five DTPA bis(amide)s have been synthesized and characterized by means of 1 H NMR , FT IR and elemental analyses. The stability constants of their Gd 3+ complexes have been measured using a simple spectrophotometric method. The results show that the complexing properties of the ligands in comparison with those of DTPA are affected by converting two carboxyl groups to amide groups. The relaxation studies have shown that the relaxivity of the chelates is similar to that of Gd DTPA, indicating that in solution all the chelates have one water molecule directly coordinated to the metal ion. Only one water molecule in inner coordination sphere suggests the coordination of the carboxamide oxygen to gadolinium ion, which agrees with the FT IR results.
文摘The immunostimulatory property of a synthetic polyphosphoramidate based on stearyl tyrosine (PPST) is described. The immunostimulatory activity of this negatively charged polymer was investigated in vitro through examining the effect on the mitogen induced lymphocytes proliferation by a tetrazolium based colormetric assay and also through studying the primary plaque forming cells (IgM PFC) responses of Balb/c mice after the intraperitoneal (i.p.) injection of the polymer with sheep red blood cells (SRBC). PPST exhibits specific and high immunostimulatory activity in vitro by the stimulation on lipopolysaccharide(LPS) induced murine B cells proliferation, which is probably due to the interaction between the polymer with LPS responding B lymphocytes. This polymer also makes a significant increase of single antibody producing cells. The result shows that the stimulation rate to IgM PFC responses of Balb/c mice achieved 77.9% ( p <0.01) when 160 mg/kg of PPST was injected 4 h before with SRBC.
文摘THE CURRENT SITUATIONBefore the founding of the People’s Republic of China in 1949. China’s higher medical education was very backward. In the 20 years before 1949. graduates from institutions of higher medical education totalled less than 10 000. In 1949. there were only 44 medical and pharmaceutical schools with 18 800 undergraduates. The higher medical education has taken a tortuous course of development after the founding of the People’s Republic of China. The first phase (1949-1965) was a period of prelimi-nary formation of medical education system of new China. During this period, the experience of the former Soviet Union was followed in determining the objectives of higher medical education, the length of the curriculum, specialties, the structure of the curriculum, the contents of teaching, etc. and a preliminary system was instituted. The second phase (1966-1976) was a time of chaos during which the normal educational program was disrupted. The third phase started in 1977. The wrong line was re
文摘DTPA was covalently conjugated to the copolymer of L lysine and L tyrosine, then transchelated with Gd EDTA,the resultant polymer chelates were further reacted with 6 O bromoacetyl D galactose or methyl lactobionyloxyacetate to give PLT(Gd DTPA) with galactose moiety as liver targeting group.These macromolecular MRI contrast agents were characterized by means of FT IR, ICP AES, elementary analyses and UV Vis spectrophotometry. Their in vitro relaxivity and liver targeting property in mice were also investigated.
基金Project supported by the National Natural Science Foundation of China Doctoral Training Foundation of the State Education Commission of China
文摘A block copolymer composed of hydrophilic and crystallinic polyethylene oxide and hydrophobic and non-crystallinic polymethyl methacrylate (PMMA) was prepared by sequential initiation of alkoxy-anion and charge transfer complex using p-aminophenol as parent compound. The structure of copolymer was characterized by GPC, IR, 1H NMR and DSC in detail. The propagation of PMMA chain is dependent on the molecular weight and concentration of the first block PEO and also the polarity of solvents. The reasons are discussed.
