Background,aim,and scope Soil saturated hydraulic conductivity(K_(s))is a key parameter in the hydrological cycle of soil;however,we have very limited understanding of K_(s) characteristics and the factors that inf lu...Background,aim,and scope Soil saturated hydraulic conductivity(K_(s))is a key parameter in the hydrological cycle of soil;however,we have very limited understanding of K_(s) characteristics and the factors that inf luence this key parameter in the Mu Us sandy land(MUSL).Quantifying the impact of changes in land use in the Mu Us sandy land on K_(s) will provide a key foundation for understanding the regional water cycle,but will also provide a scientific basis for the governance of the MUSL.Materials and methods In this study,we determined K_(s) and the basic physical and chemical properties of soil(i.e.,organic matter,bulk density,and soil particle composition)within the first 100 cm layer of four different land use patterns(farmland,tree,shrub,and grassland)in the MUSL.The vertical variation of K_(s) and the factors that influence this key parameter were analyzed and a transfer function for estimating K_(s) was established based on a multiple stepwise regression model.Results The K_(s) of farmland,tree,and shrub increased gradually with soil depth while that of grassland remained unchanged.The K_(s) of the four patterns of land use were moderately variable;mean K_(s)values were ranked as follows:grassland(1.38 mm·min^(-1))<tree(1.76 mm·min^(-1))<farmland(1.82 mm·min^(-1))<shrub(3.30 mm·min^(-1)).The correlation between K_(s) and organic matter,bulk density,and soil particle composition,varied across different land use patterns.A multiple stepwise regression model showed that silt,coarse sand,bulk density,and organic matter,were key predictive factors for the K_(s) of farmland,tree,shrub,and grassland,in the MUSL.Discussion The vertical distribution trend for K_(s) in farmland is known to be predominantly influenced by cultivation,fertilization,and other factors.The general aim is to improve the water-holding capacity of shallow soil on farmland(0-30 cm in depth)to conserve water and nutrients;research has shown that the K_(s) of farmland increases with soil depth.The root growth of tree and shrub in sandy land exerts mechanical force on the soil due to biophysical processes involving rhizospheres,thus leading to a significant change in K_(s).We found that shallow high-density fine roots increased the volume of soil pores and eliminated large pores,thus resulting in a reduction in shallow K_(s).Therefore,the K_(s) of tree and shrub increased with soil depth.Analysis also showed that the K_(s) of grassland did not change significantly and exhibited the lowest mean value when compared to other land use patterns.This finding was predominantly due to the shallow root system of grasslands and because this land use pattern is not subject to human activities such as cultivation and fertilization;consequently,there was no significant change in K_(s) with depth;grassland also had the lowest mean K_(s).We also established a transfer function for K_(s) for different land use patterns in the MUSL.However,the predictive factors for K_(s) in different land use patterns are known to be affected by soil cultivation methods,vegetation restoration modes,the distribution of soil moisture,and other factors,thus resulting in key differences.Therefore,when using the transfer function to predict K_(s) in other areas,it will be necessary to perform parameter calibration and further verification.Conclusions In the MUSL,the K_(s) of farmland,tree,and shrub gradually increased with soil depth;however,the K_(s) of grassland showed no significant variation in terms of vertical distribution.The mean K_(s) values of different land use patterns were ranked as follows:shrub>farmland>tree>grassland;all land use patterns showed moderate levels of variability.The K_(s) for different land use patterns exhibited differing degrees of correlation with soil physical and chemical properties;of these,clay,silt,sand,bulk density,and organic matter,were identified as important variables for predicting K_(s) in farmland,tree,shrub,and grassland,respectively.Recommendations and perspectives In this study,we used a stepwise multiple regression model to establish a transfer function prediction model for K_(s) for different land use patterns;this model possessed high estimation accuracy.The ability to predict K_(s) in the MUSL is very important in terms of the conservation of water and nutrients.展开更多
Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductan...Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation.展开更多
This paper analyzed the water-retention mechanism of feldspathic sandstone （fine-（〈 1 mm diam.） and gravel-sized （2-3 cm diam.） in Mu Us Sandy Land, Northwest China. The objective of this study is to study the e...This paper analyzed the water-retention mechanism of feldspathic sandstone （fine-（〈 1 mm diam.） and gravel-sized （2-3 cm diam.） in Mu Us Sandy Land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on water retention in sandy land. The results showed that as the proportion of fine feldspathic sandstone in the sandy land soil increased, the soil texture changed from sand to silt loam, the capillary po- rosity gradually increased from 26.3% to 44.9%, and the soil saturated hydraulic conductivity decreased from 7.10 ram/rain to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy land soil, playing the role of a ＇water absorbent＇ and ＇water retaining agent＇ in sandy land. Amendment with feldspathic sandstone can increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land soil and increase soil water retention.展开更多
The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples...The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples, and quartz-matrix samples with variable laminated shale, dispersed shale, and pyrite content and then perform petrophysics experiments to assess the effect of pyrite content on the conductivity of pyrite-bearing shaly sands. Second, based on the differences in conductivity and conduction pathways and geometries because of the variable composition of the pyrite-bearing laminated and dispersed shaly sands, we divide the shaly sands into their components, i.e., laminated shale, quartz grains, pyrite grains, hydrocarbon, dispersed shale, microscopic capillary water, and mobile water. A generalized resistivity model is proposed to describe the conductivity of pyrite- bearing laminated and dispersed shaly sands, based on the combined conductivity differential equation and generalized Archie equation. In the generalized resistivity model, the conductivity differential equation is used to describe the conductivity of dispersed inclusions in a host, whereas the generalized Archie equation is used to describe the conductivity of two conducting phases. Moreover, parallel conductance theory is used to describe the conductivity of dispersed shaly sands and laminated shale. Theoretical analysis suggests that the proposed model satisfies the physical constraints and the model and experimental results agree. The resistivity and resistivity index of shaly sands decrease with increasing conductivity and pyrite. Finally, the accuracy of the resistivity model is assessed based on experimental data from 46 synthetic core samples with different oil saturation. The model can describe the conductivity of clean pyrite-matrix samples, and quartz-matrix samples with different volumes of laminated shale, dispersed shale, and pyrite. An accurate saturation model of pyrite-bearing laminated and dispersed shaly sands is thus obtained and the log data interpretation in complex shaly sands can improve with the proposed model.展开更多
Wind erosion is a major cause of land desertification and sandstorm formation in arid and semi-arid areas.The objective of this study was to evaluate the potential of soybeans crude extract induced calcium carbonate p...Wind erosion is a major cause of land desertification and sandstorm formation in arid and semi-arid areas.The objective of this study was to evaluate the potential of soybeans crude extract induced calcium carbonate precipitation(SICP)on reducing wind erosion risk of sandy soil.Field tests were carried out in Ulan Buh Desert,Ningxia Hui Autonomous Region,China.Results showed that the SICP method could significantly enhance the surface strength and wind erosion resistance of the topsoil.The optimal cementation solution(urea-CaCl2)concentration and spraying volume,according to experiments conducted on sandy land,were 0.2 mol/L and 4 L/m^2,respectively.Under this condition,the CaCO3 content was approximately 0.45%,the surface strength of sandy soil could reach 306.2 kPa,and the depth of wind erosion was approximately zero,after 30 d completion of SICP treatment.Soil surface strength declined with the increase of time,and long-term sand fixation effects of SICP treatment varied depending on topography.Whereas wind erosion in the top area of the windward slope was remarkable,sandy soils on the bottom area of the windward slope still maintained a relatively high level of surface strength and a low degree of wind erosion 12 month after SICP treatment.Scanning electron microscopy(SEM)tests with energy dispersive X-ray(EDX)confirmed the precipitation of CaCO3 and its bridge effect.These findings suggested that the SICP method is a promising candidate to protect sandy soil from wind erosion in desert areas.展开更多
Crohn's disease is a chronic inflammatory disorder of the gastrointestinal tract that is defi ned by relapsing and remitting episodes. Tumor necrosis factor alpha (TNF-α) appears to play a central role in the pat...Crohn's disease is a chronic inflammatory disorder of the gastrointestinal tract that is defi ned by relapsing and remitting episodes. Tumor necrosis factor alpha (TNF-α) appears to play a central role in the pathophysiology of the disease. Standard therapies for inflammatory bowel disease fail to induce remission in about 30% of patients. Biological therapies have been associated with an increased incidence of infections, especially infection by Mycobacterium tuberculosis (Mtb). Thalidomide is an oral immunomodulatory agent with anti-TNF-α properties. Recent studies have suggested that thalidomide is effective in refractory luminal and fistulizing Crohn's disease. Thalidomide costimulates T lymphocytes, with greater effect on CD8+ than on CD4+ T cells, which contributes to the protective immune response to Mtb infection. We present a case of Crohn's disease with gastric, ileal, colon and rectum involvement as well as steroid dependency, which progressed with loss of response to infliximabafter three years of therapy. The thorax computed tomography scan demonstrated a pulmonary nodule suspected to be Mtb infection. The patient was started on thalidomide therapy and exhibited an excellent response.展开更多
Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporat...Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporation in a sandy soil from Hebei Province, China. Biochar had strong absorption ability in the sandy soil. The ratio of water content in the biochar to that in the sandy soil was less than the corresponding ratio of porosity. Because of the different hydraulic properties between the sandy soil and the biochar, the saturated hydraulic conductivity of the sandy soil gradually decreased with the increasing biochar addition. The biochar with larger pore volume and average pore diameter had better water retention. More water was retained in the sandy soil when the biochar was added in a single layer, but not when the biochar was uniformly mixed with soil. Particle size of the added biochar had a significant influence on the hydraulic properties of the mixture of sand and biochar. Grinding the biochar into powder destroyed the pore structure, which simultaneously reduced the water absorption ability and hydraulic conductivity of the biochar. For this reason, adding biochar powder to the sandy soil would not decrease the water evaporation loss of the soil itself.展开更多
Background and objective： Rivaroxaban is a new oral anticoagulant for stroke prevention in patients with non-valvular atrial fibrillation （NVAF）, which has less drug-food interaction than warfarin. We conducted thi...Background and objective： Rivaroxaban is a new oral anticoagulant for stroke prevention in patients with non-valvular atrial fibrillation （NVAF）, which has less drug-food interaction than warfarin. We conducted this pro- spective randomized study to evaluate the metabolic benefits as well as the safety and efficacy with rivaroxaban versus warfarin in patients with NVAF following radiofrequency catheter ablation （RFCA）. Methods： From April to July 2014, 60 patients with NVAF undergoing RFCA were prospectively enrolled in our study. Following RFCA, all patients were randomly assigned to receive rivaroxaban （Group R, n=30） or warfarin （Group W, n=30）. Metabolic indices including serum total protein, albumin, globulin, and high-density lipoprotein （HDL） as well as bleeding, stroke, and systemic thromboembolism events were evaluated and compared during follow-up after 15, 30, 60, and 90 d of RFCA procedure. Results： Serum total protein, albumin, globulin, and HDL levels were all significantly elevated at each follow-up stage in Group R when compared to the baseline （P〈0.05 respectively）. In Group W, the metabolic indices decreased at first and then had an increasing trend. There were no deaths or thromboembolic complications in each group. The prevalence of total bleeding complications was similar between Group R and Group W （11/30, 36.7% vs. 10/30, 33.3%, P=0.70）. Conclusions： Patients with NVAF receiving rivaroxaban after RFCA procedures appear to benefit from a metabolic perspective compared with warfarin, providing practical clinical reference for the choice of the anticoagulant. Rivaroxaban seems to be as safe and effective in preventing thromboembolic events as warfarin for these patients.展开更多
Radix Adenophorae, a traditional Chinese medicine, has been reported to have a variety of biological functions. In the present study, a polysaccharide component, Radix Adenophorae Polysaccharide （RAPS）, was purified...Radix Adenophorae, a traditional Chinese medicine, has been reported to have a variety of biological functions. In the present study, a polysaccharide component, Radix Adenophorae Polysaccharide （RAPS）, was purified from Radix Adenophorae by decoloring with ADS-7 macroporous adsorption resin, DEAE-52 cellulose ion-exchange chromatography, and Sephacryl S-300HR gel chromatography, with the purity of 98.3% and a molecular weight of 1.8 × 104 Da. The cell viability assay and microscopic examination revealed that RAPS promoted the proliferation and activation of macrophages. At 400 μg·mL-1, RAPS stimulated RAW264.7 cell proliferation by 1.91-fold compared with the control. Meanwhile, RAPS significantly increased the secretion of pro-inflammatory cytokines （TNF-a and IL-6） in a dose-dependent manner in the supernatant of RAW264.7 cell culture as determined by ELISA. At 400 μg·mL-1, the production of TNF-a was 20.8-fold higher than that of the control. Simultaneously, the production of nitric oxide （NO） and the expression of inducible nitric oxide synthase （iNOS） were increased in RAW264.7 cells incubated with RAPS, as measured by Griess assay and Western blot analysis. The NO production of cells treated with RAPS （400 μg·mL-1） reached 15.8 μmol·L-L, which was 30.4-fold higher than that of the control （0.53 μmol·L-1）. These data suggested that RAPS may enhance the immune function and protect against exogenous pathogens by activating macrophages.展开更多
文摘Background,aim,and scope Soil saturated hydraulic conductivity(K_(s))is a key parameter in the hydrological cycle of soil;however,we have very limited understanding of K_(s) characteristics and the factors that inf luence this key parameter in the Mu Us sandy land(MUSL).Quantifying the impact of changes in land use in the Mu Us sandy land on K_(s) will provide a key foundation for understanding the regional water cycle,but will also provide a scientific basis for the governance of the MUSL.Materials and methods In this study,we determined K_(s) and the basic physical and chemical properties of soil(i.e.,organic matter,bulk density,and soil particle composition)within the first 100 cm layer of four different land use patterns(farmland,tree,shrub,and grassland)in the MUSL.The vertical variation of K_(s) and the factors that influence this key parameter were analyzed and a transfer function for estimating K_(s) was established based on a multiple stepwise regression model.Results The K_(s) of farmland,tree,and shrub increased gradually with soil depth while that of grassland remained unchanged.The K_(s) of the four patterns of land use were moderately variable;mean K_(s)values were ranked as follows:grassland(1.38 mm·min^(-1))<tree(1.76 mm·min^(-1))<farmland(1.82 mm·min^(-1))<shrub(3.30 mm·min^(-1)).The correlation between K_(s) and organic matter,bulk density,and soil particle composition,varied across different land use patterns.A multiple stepwise regression model showed that silt,coarse sand,bulk density,and organic matter,were key predictive factors for the K_(s) of farmland,tree,shrub,and grassland,in the MUSL.Discussion The vertical distribution trend for K_(s) in farmland is known to be predominantly influenced by cultivation,fertilization,and other factors.The general aim is to improve the water-holding capacity of shallow soil on farmland(0-30 cm in depth)to conserve water and nutrients;research has shown that the K_(s) of farmland increases with soil depth.The root growth of tree and shrub in sandy land exerts mechanical force on the soil due to biophysical processes involving rhizospheres,thus leading to a significant change in K_(s).We found that shallow high-density fine roots increased the volume of soil pores and eliminated large pores,thus resulting in a reduction in shallow K_(s).Therefore,the K_(s) of tree and shrub increased with soil depth.Analysis also showed that the K_(s) of grassland did not change significantly and exhibited the lowest mean value when compared to other land use patterns.This finding was predominantly due to the shallow root system of grasslands and because this land use pattern is not subject to human activities such as cultivation and fertilization;consequently,there was no significant change in K_(s) with depth;grassland also had the lowest mean K_(s).We also established a transfer function for K_(s) for different land use patterns in the MUSL.However,the predictive factors for K_(s) in different land use patterns are known to be affected by soil cultivation methods,vegetation restoration modes,the distribution of soil moisture,and other factors,thus resulting in key differences.Therefore,when using the transfer function to predict K_(s) in other areas,it will be necessary to perform parameter calibration and further verification.Conclusions In the MUSL,the K_(s) of farmland,tree,and shrub gradually increased with soil depth;however,the K_(s) of grassland showed no significant variation in terms of vertical distribution.The mean K_(s) values of different land use patterns were ranked as follows:shrub>farmland>tree>grassland;all land use patterns showed moderate levels of variability.The K_(s) for different land use patterns exhibited differing degrees of correlation with soil physical and chemical properties;of these,clay,silt,sand,bulk density,and organic matter,were identified as important variables for predicting K_(s) in farmland,tree,shrub,and grassland,respectively.Recommendations and perspectives In this study,we used a stepwise multiple regression model to establish a transfer function prediction model for K_(s) for different land use patterns;this model possessed high estimation accuracy.The ability to predict K_(s) in the MUSL is very important in terms of the conservation of water and nutrients.
文摘Seasonal changes in the photosynthetic characteristics of Ammopiptantus mongolicus (Maxim. )Chen f. were studied. When the net photosynthetic rate decreased with the elevation of air temperature, thestomatal conductance and stomatal limitation value tended to decline simultaneously, while the interoellularCO2 concentration was increased. According to the two criteria discriminating the stomatal limitation of Photosynthesis suggeSted by Fmrquhar and Sharkey, the seasonal changes in these parameters indicated that the decrease in Pn may not be due to stomatal factor. These studies proved that the relative contents of the large subunit of Rubisco and the photochemical activities correlated with the seasonal changes in the net photosyntheticrate, whieh may show that these two factors contribute primarily to the seasonal changeS in CO2 assimilation.
基金Under the auspices of Key Direction Program of Chinese Academy of Science(No.KZCX2-YW-Q06-03)MajorState Basic Research Development Program of China(No.2009CB421103)+1 种基金National Natural Science Foundation of China(No.41001050)Major Science and Technology Program for Water Pollution Control and Treatment(No.2012ZX07201004)
文摘This paper analyzed the water-retention mechanism of feldspathic sandstone （fine-（〈 1 mm diam.） and gravel-sized （2-3 cm diam.） in Mu Us Sandy Land, Northwest China. The objective of this study is to study the effect of feldspathic sandstone amendment on water retention in sandy land. The results showed that as the proportion of fine feldspathic sandstone in the sandy land soil increased, the soil texture changed from sand to silt loam, the capillary po- rosity gradually increased from 26.3% to 44.9%, and the soil saturated hydraulic conductivity decreased from 7.10 ram/rain to 0.07 mm/min. Feldspathic sandstone gravel formed micro-reservoirs in the sandy land soil, playing the role of a ＇water absorbent＇ and ＇water retaining agent＇ in sandy land. Amendment with feldspathic sandstone can increase water retention in the arable layer of sandy land by 67%. This study provides a theoretical basis for the amelioration of sandy land on a large scale. It can be concluded that amendment with feldspathic sandstone can improve the physical properties of sandy land soil and increase soil water retention.
基金This work was supported by the National Natural Science Foundation of China （No. 41274110）, and the Northeast Petroleum University Innovation Foundation for Postgraduate （No. YJSCX2016-003NEPU）.
文摘The conductance of pyrite-bearing laminated and dispersed shaly sands is not well understood and resistivity models for pyrite-bearing shaly sands are nonexistent. Thus, we first synthesize clean pyrite-matrix samples, and quartz-matrix samples with variable laminated shale, dispersed shale, and pyrite content and then perform petrophysics experiments to assess the effect of pyrite content on the conductivity of pyrite-bearing shaly sands. Second, based on the differences in conductivity and conduction pathways and geometries because of the variable composition of the pyrite-bearing laminated and dispersed shaly sands, we divide the shaly sands into their components, i.e., laminated shale, quartz grains, pyrite grains, hydrocarbon, dispersed shale, microscopic capillary water, and mobile water. A generalized resistivity model is proposed to describe the conductivity of pyrite- bearing laminated and dispersed shaly sands, based on the combined conductivity differential equation and generalized Archie equation. In the generalized resistivity model, the conductivity differential equation is used to describe the conductivity of dispersed inclusions in a host, whereas the generalized Archie equation is used to describe the conductivity of two conducting phases. Moreover, parallel conductance theory is used to describe the conductivity of dispersed shaly sands and laminated shale. Theoretical analysis suggests that the proposed model satisfies the physical constraints and the model and experimental results agree. The resistivity and resistivity index of shaly sands decrease with increasing conductivity and pyrite. Finally, the accuracy of the resistivity model is assessed based on experimental data from 46 synthetic core samples with different oil saturation. The model can describe the conductivity of clean pyrite-matrix samples, and quartz-matrix samples with different volumes of laminated shale, dispersed shale, and pyrite. An accurate saturation model of pyrite-bearing laminated and dispersed shaly sands is thus obtained and the log data interpretation in complex shaly sands can improve with the proposed model.
基金Supported by The Guangdong Provincial Science and Technology Programs,China,No.2009A030301013the Scientific Funds of Guangzhou Medical College,China,No.2010A29+1 种基金National Natural Science Foundation of China,No.30700398 and 81172831Natural Science Foundation of Guangdong Province,No.10151008901000200
文摘AIM： To observe the synergistic effects of hyperthermia in oxaliplatin-induced cytotoxicity in human colon adenocarcinoma Lovo cells.
基金Projects(51978244,51979088,51608169)supported by the National Natural Science Foundation of China。
文摘Wind erosion is a major cause of land desertification and sandstorm formation in arid and semi-arid areas.The objective of this study was to evaluate the potential of soybeans crude extract induced calcium carbonate precipitation(SICP)on reducing wind erosion risk of sandy soil.Field tests were carried out in Ulan Buh Desert,Ningxia Hui Autonomous Region,China.Results showed that the SICP method could significantly enhance the surface strength and wind erosion resistance of the topsoil.The optimal cementation solution(urea-CaCl2)concentration and spraying volume,according to experiments conducted on sandy land,were 0.2 mol/L and 4 L/m^2,respectively.Under this condition,the CaCO3 content was approximately 0.45%,the surface strength of sandy soil could reach 306.2 kPa,and the depth of wind erosion was approximately zero,after 30 d completion of SICP treatment.Soil surface strength declined with the increase of time,and long-term sand fixation effects of SICP treatment varied depending on topography.Whereas wind erosion in the top area of the windward slope was remarkable,sandy soils on the bottom area of the windward slope still maintained a relatively high level of surface strength and a low degree of wind erosion 12 month after SICP treatment.Scanning electron microscopy(SEM)tests with energy dispersive X-ray(EDX)confirmed the precipitation of CaCO3 and its bridge effect.These findings suggested that the SICP method is a promising candidate to protect sandy soil from wind erosion in desert areas.
文摘Crohn's disease is a chronic inflammatory disorder of the gastrointestinal tract that is defi ned by relapsing and remitting episodes. Tumor necrosis factor alpha (TNF-α) appears to play a central role in the pathophysiology of the disease. Standard therapies for inflammatory bowel disease fail to induce remission in about 30% of patients. Biological therapies have been associated with an increased incidence of infections, especially infection by Mycobacterium tuberculosis (Mtb). Thalidomide is an oral immunomodulatory agent with anti-TNF-α properties. Recent studies have suggested that thalidomide is effective in refractory luminal and fistulizing Crohn's disease. Thalidomide costimulates T lymphocytes, with greater effect on CD8+ than on CD4+ T cells, which contributes to the protective immune response to Mtb infection. We present a case of Crohn's disease with gastric, ileal, colon and rectum involvement as well as steroid dependency, which progressed with loss of response to infliximabafter three years of therapy. The thorax computed tomography scan demonstrated a pulmonary nodule suspected to be Mtb infection. The patient was started on thalidomide therapy and exhibited an excellent response.
文摘Biochar, as a kind of soil amendment, has important effects on soil water retention. In this research, 4 different kinds of biochars were used to investigate their influences on hydraulic properties and water evaporation in a sandy soil from Hebei Province, China. Biochar had strong absorption ability in the sandy soil. The ratio of water content in the biochar to that in the sandy soil was less than the corresponding ratio of porosity. Because of the different hydraulic properties between the sandy soil and the biochar, the saturated hydraulic conductivity of the sandy soil gradually decreased with the increasing biochar addition. The biochar with larger pore volume and average pore diameter had better water retention. More water was retained in the sandy soil when the biochar was added in a single layer, but not when the biochar was uniformly mixed with soil. Particle size of the added biochar had a significant influence on the hydraulic properties of the mixture of sand and biochar. Grinding the biochar into powder destroyed the pore structure, which simultaneously reduced the water absorption ability and hydraulic conductivity of the biochar. For this reason, adding biochar powder to the sandy soil would not decrease the water evaporation loss of the soil itself.
文摘Background and objective： Rivaroxaban is a new oral anticoagulant for stroke prevention in patients with non-valvular atrial fibrillation （NVAF）, which has less drug-food interaction than warfarin. We conducted this pro- spective randomized study to evaluate the metabolic benefits as well as the safety and efficacy with rivaroxaban versus warfarin in patients with NVAF following radiofrequency catheter ablation （RFCA）. Methods： From April to July 2014, 60 patients with NVAF undergoing RFCA were prospectively enrolled in our study. Following RFCA, all patients were randomly assigned to receive rivaroxaban （Group R, n=30） or warfarin （Group W, n=30）. Metabolic indices including serum total protein, albumin, globulin, and high-density lipoprotein （HDL） as well as bleeding, stroke, and systemic thromboembolism events were evaluated and compared during follow-up after 15, 30, 60, and 90 d of RFCA procedure. Results： Serum total protein, albumin, globulin, and HDL levels were all significantly elevated at each follow-up stage in Group R when compared to the baseline （P〈0.05 respectively）. In Group W, the metabolic indices decreased at first and then had an increasing trend. There were no deaths or thromboembolic complications in each group. The prevalence of total bleeding complications was similar between Group R and Group W （11/30, 36.7% vs. 10/30, 33.3%, P=0.70）. Conclusions： Patients with NVAF receiving rivaroxaban after RFCA procedures appear to benefit from a metabolic perspective compared with warfarin, providing practical clinical reference for the choice of the anticoagulant. Rivaroxaban seems to be as safe and effective in preventing thromboembolic events as warfarin for these patients.
基金supported by the National Science and Technology Major Project Foundation of China(No.2012ZX09102301-003)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Radix Adenophorae, a traditional Chinese medicine, has been reported to have a variety of biological functions. In the present study, a polysaccharide component, Radix Adenophorae Polysaccharide （RAPS）, was purified from Radix Adenophorae by decoloring with ADS-7 macroporous adsorption resin, DEAE-52 cellulose ion-exchange chromatography, and Sephacryl S-300HR gel chromatography, with the purity of 98.3% and a molecular weight of 1.8 × 104 Da. The cell viability assay and microscopic examination revealed that RAPS promoted the proliferation and activation of macrophages. At 400 μg·mL-1, RAPS stimulated RAW264.7 cell proliferation by 1.91-fold compared with the control. Meanwhile, RAPS significantly increased the secretion of pro-inflammatory cytokines （TNF-a and IL-6） in a dose-dependent manner in the supernatant of RAW264.7 cell culture as determined by ELISA. At 400 μg·mL-1, the production of TNF-a was 20.8-fold higher than that of the control. Simultaneously, the production of nitric oxide （NO） and the expression of inducible nitric oxide synthase （iNOS） were increased in RAW264.7 cells incubated with RAPS, as measured by Griess assay and Western blot analysis. The NO production of cells treated with RAPS （400 μg·mL-1） reached 15.8 μmol·L-L, which was 30.4-fold higher than that of the control （0.53 μmol·L-1）. These data suggested that RAPS may enhance the immune function and protect against exogenous pathogens by activating macrophages.
