Currently, surface nuclear magnetic resonance （SNMR） method is the only geophysical method that detects groundwater directly. In this paper, we investigate the effect of elliptical polarization in the perpendicular ...Currently, surface nuclear magnetic resonance （SNMR） method is the only geophysical method that detects groundwater directly. In this paper, we investigate the effect of elliptical polarization in the perpendicular excitation magnetic field. The effect of elliptical polarization is clearly visible in our ellipticity calculation and it can cause strong distortion to the excitation field in the presence of high subsurface conductivities. By examining the co-rotating and counter-rotating components of the field, we show that elliptical polarization affects transmitting and receiving processes differently and that a clear phase lag exists between transmitter loop and receiver loop. Finally, we derive the response function of coincident loops and calculate proton tip angles, the kernel function and SNMR response curves of a 1D aquifer model. Based on the simulations, we conclude that the elliptical polarization and phase lag can significantly affect SNMR response and it is essential to include elliptical polarization in SNMR modeling and data interpretation.展开更多
Propolis is a natural resin used around the world to treatment of several diseases. We evaluated the effect of Brazilian propolis (P1) in guinea pig isolated trachea in vitro contracted with hista-mine, in paw oedema ...Propolis is a natural resin used around the world to treatment of several diseases. We evaluated the effect of Brazilian propolis (P1) in guinea pig isolated trachea in vitro contracted with hista-mine, in paw oedema induced by histamine in mice and anti-ulcerogenic effect of propolis formulation in mice. We used a P1 extract from South of Brazil to produce a formulation containing sodium bicarbonate and propolis dry extract (2%). In the guinea pig trachea Brazilian propolis extract (10 μg/mL) produced a non-significant inhibition in the cumulative response curve for histamine. However, the dose of 100 μg/mL shown had a significant inhibitory effect on the contraction induced by histamine (51% ± 5%). In the mouse paw oedema induced by intraplantar injection of histamine (50 μg/paw), the results showed that the treatment of the mice with P1 (10 or 100 mg/Kg (p.o) or 1 or 10 mg/Kg (i.p)), 0.5 h beforehand, significantly inhibited the paw oedema with maximal inhibition (MI) of 25% or 42% by p.o. route or 22% or 37% by i.p. route, respectively. Finally we have pre-treated mice with P1 formulation (20 mg/Kg or 40 mg/Kg, p.o, one time) or vehicle (powder) in animals submitted to diclofenac-induced ulcer, after 8 h P1 formulation inhibited of 43% or 83% of ulcers scores, respectively. Results showed that P1 formulation inhibited the ulcerogenic effect induced by diclofenac. Results suggested also, at least in part, the antiulcerogenic effect of formulation containing standardized extract of propolis can be due to the antagonistic action on the histaminergic system.展开更多
基金supported by the National Natural Science Foundation of China(No.40974040)the SinoProbe Projects(No. SinoProbe-01-03-02)
文摘Currently, surface nuclear magnetic resonance （SNMR） method is the only geophysical method that detects groundwater directly. In this paper, we investigate the effect of elliptical polarization in the perpendicular excitation magnetic field. The effect of elliptical polarization is clearly visible in our ellipticity calculation and it can cause strong distortion to the excitation field in the presence of high subsurface conductivities. By examining the co-rotating and counter-rotating components of the field, we show that elliptical polarization affects transmitting and receiving processes differently and that a clear phase lag exists between transmitter loop and receiver loop. Finally, we derive the response function of coincident loops and calculate proton tip angles, the kernel function and SNMR response curves of a 1D aquifer model. Based on the simulations, we conclude that the elliptical polarization and phase lag can significantly affect SNMR response and it is essential to include elliptical polarization in SNMR modeling and data interpretation.
文摘Propolis is a natural resin used around the world to treatment of several diseases. We evaluated the effect of Brazilian propolis (P1) in guinea pig isolated trachea in vitro contracted with hista-mine, in paw oedema induced by histamine in mice and anti-ulcerogenic effect of propolis formulation in mice. We used a P1 extract from South of Brazil to produce a formulation containing sodium bicarbonate and propolis dry extract (2%). In the guinea pig trachea Brazilian propolis extract (10 μg/mL) produced a non-significant inhibition in the cumulative response curve for histamine. However, the dose of 100 μg/mL shown had a significant inhibitory effect on the contraction induced by histamine (51% ± 5%). In the mouse paw oedema induced by intraplantar injection of histamine (50 μg/paw), the results showed that the treatment of the mice with P1 (10 or 100 mg/Kg (p.o) or 1 or 10 mg/Kg (i.p)), 0.5 h beforehand, significantly inhibited the paw oedema with maximal inhibition (MI) of 25% or 42% by p.o. route or 22% or 37% by i.p. route, respectively. Finally we have pre-treated mice with P1 formulation (20 mg/Kg or 40 mg/Kg, p.o, one time) or vehicle (powder) in animals submitted to diclofenac-induced ulcer, after 8 h P1 formulation inhibited of 43% or 83% of ulcers scores, respectively. Results showed that P1 formulation inhibited the ulcerogenic effect induced by diclofenac. Results suggested also, at least in part, the antiulcerogenic effect of formulation containing standardized extract of propolis can be due to the antagonistic action on the histaminergic system.
