The effect of the amount of precipitant ammonia on the Cu0/Cu+ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of a...The effect of the amount of precipitant ammonia on the Cu0/Cu+ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu+ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG) shows that the selectivity of EG depends on the Cu0/Cu+ratio. Catalyst prepared with the addition of ammonia solution at n(NH3)/n(Cu2+) = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu+ratio upon reduction and thus has a higher selectivity for EG.展开更多
BACKGROUND No guideline recommends antiviral therapy for hepatitis B e antigen(HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus(HBV)DNA...BACKGROUND No guideline recommends antiviral therapy for hepatitis B e antigen(HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus(HBV)DNA viral load.AIM To evaluate the feasibility and safety of a Chinese herbal formula as a therapeutic option for chronic HBV infection.METHODS In total,395 patients(30–65 years old)with confirmed HBeAg-positive chronic hepatitis B infection and persistently normal alanine aminotransferase were randomized to receive either Chinese herbal formula or placebo for 96 wk.Endpoints to evaluate therapeutic efficacy included:(1)HBV DNA levels decreased to less than 4 log10 IU/mL at weeks 48 and 96;and(2)HBeAg clearance and seroconversion rates at weeks 48 and 96.RESULTS HBV DNA levels≤4 log10 IU/mL were 10.05%at week 48 and 18.59%at week 96 in the treatment group.The HBeAg clearance and conversion rates were 8.54%and 8.04%at week 48 and 16.08%and 14.57%at week 96,respectively.However,HBV DNA levels≤4 log10 IU/mL were 2.55%and 2.55%at weeks 48 and 96,respectively,and the HBeAg clearance rates were 3.06%and 5.61%at weeks 48 and 96,respectively,in the control group.The quantitative hepatitis B surface antigen and HBeAg levels at baseline and changes during the treatment period as well as the alanine aminotransferase elevation at weeks 12 and 24 were strong predictors of HBeAg clearance.CONCLUSION High rates of HBV DNA reduction,HBeAg clearance and seroconversion could be achieved with Chinese herbal formula treatments,and the treatments were relatively safe for HBeAg-positive chronic hepatitis B-infected patients with persistently normal alanine aminotransferase.The ability of the compound to modulate host immune function probably contributed to this effect.展开更多
A series of diphenyl-sulfide (Ph2S)-immobilized Pd/C catalysts (Pd-Ph2Scx)/C) were prepared using the wetness-impregnation and immobilization method. Pd-Ph2S(x)/C catalysts employed for the hydro- genation of o...A series of diphenyl-sulfide (Ph2S)-immobilized Pd/C catalysts (Pd-Ph2Scx)/C) were prepared using the wetness-impregnation and immobilization method. Pd-Ph2S(x)/C catalysts employed for the hydro- genation of o-chloronitrobenzene showed very high selectivity. The structure of Pd-Ph2Scx)/C with different molar ratio of ligand (x-values) was characterized by XPS and TG-DSC-MS. The results suggest a "saturated" surface ratio of Ph2S/Pd (about 0.3) was formed on the Pd-Ph2S(x)[C catalysts surface. The Ph2S immobilized on the Pd particle is quite stable, and the desorption of Ph2S or dissociative loss of phenyl group was only found at temperatures above 500 K. The possible catalytic mechanism of the Pd-Ph2S(x)/C catalyst was also discussed.展开更多
BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have bee...BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have been linked to PFIC type 4(PFIC4),which predominantly presents in childhood.However,there are only limited data from adults with TJP2-related PFIC4.We report a family with an autosomal recessive disorder with a novel variant in the TJP2 gene in adults with very variable expression of PFIC4.CASE SUMMARY The index patient presented at 19 years old with liver cirrhosis and variceal bleeding and was treated with endoscopic banding and beta-blockers.In 2018,he developed primary liver cancer that was treated with radiofrequency ablation followed by liver transplantation in 2019.Genetic testing revealed a novel homozygous TJP2 variant causing PFIC4(TJP2([NM_004817.3]:c.[3334C>T];[3334C>T])).The consanguineous family consists of the father and mother(both heterozygous)and their 12 children,of which five carry the variant in a homozygous state;however,these five siblings have highly variable expression of PFIC4.Two homozygous brothers had cirrhosis and portal hypertension at diagnosis at the ages of 19 and 36.Two other homozygous brothers,age 23 and 19,and the homozygous sister,age 21,have elevated liver enzymes but presently no cirrhosis,which may suggest an age-dependent penetrance.In addition,five sisters had severe and mild intrahepatic cholestasis of pregnancy and carry the TJP2 variant in a homozygous and heterozygous state,respectively.CONCLUSION This novel TJP2 variant is associated with PFIC4 causing severe liver disease with cirrhosis and primary liver cancer in adolescents/adults.展开更多
BACKGROUND China has a high prevalence of hepatitis B virus(HBV),but most chronic hepatitis B(CHB)patients do not receive standardized antiviral therapy.There are few relevant reports addressing the outcomes of the la...BACKGROUND China has a high prevalence of hepatitis B virus(HBV),but most chronic hepatitis B(CHB)patients do not receive standardized antiviral therapy.There are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral therapy.AIM To observe the outcomes of long-term follow-up of patients with CHB without antiviral treatment.METHODS This study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to 1998.The median follow-up times were 10 and 7 years,respectively.A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control groups.The median follow-up times were 8 and 7 years,respectively.Kaplan-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma(HCC),and the Cox regression model was used to analyze the risk factors for HCC.RESULTS Among the patients in the non-antiviral group,16.9%had spontaneous decreases(HBeAg)seroconversion.In the antiviral group,87.2%of patients had undetectable HBV DNA,and 52%showed HBeAg seroconversion.Among CHB and hepatitis B cirrhosis patients,the cumulative incidence rates of HCC were 14.9%and 53.1%,respectively,in the non-antiviral group and were 10.7%and 31.9%,respectively,in the antiviral group.There was no difference between the two groups regarding the CHB patients(P=0.842),but there was a difference between the groups regarding the hepatitis B cirrhosis patients(P=0.026).The cumulative incidence rates of HCC were 1.6%and 22.3%(P=0.022)in the groups with and without spontaneous HBeAg seroconversion,respectively.The incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6%and 19.1%,respectively(P=0.051).There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistant CHB(P=0.119),but there was a significant diffe展开更多
Background Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary ...Background Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary vein potentials (PVPs). Pulmonary vein tachycardia (PVT) is the dissociated PV rhythm with a rapid rate. However, the characteristics and significance of PVT after pulmonary vein isolation in patients with AF remains unclear. Methods From June 2003 to June 2005, a total of 285 consecutive patients with drug refractory AF were included in this study, and they underwent segmental pulmonary vein ablation (SPVA) or circumferential pulmonary vein ablation (CPVA). PV isolation was the initial endpoint for both approaches with documenting disappearance or dissociation of PVPs. PVT was characterized as dissociated activities within PVs with a circle length (CL) of 〈300 ms, and was classified into organized PVT or disorganized PVT according to the variance of CL. Systematic follow-up was conducted after initial procedures. Continuous variables were analyzed by Student's t test and categorical variables were analyzed by chi-square test. Results Three hundred and fifteen PVs were ablated in 85 patients underwent SPVA approach, 400 circular lesions surrounding ipsilateral PVs (including 790 PVs) were produced in the rest of 200 patients received CPVA approach. Electrical isolation was achieved in all of these PVs. Of these, PVPs were abolished in 89.8% (992/1105) of the ablated PVs, dissociated PV rhythms were documented in the rest 10.2 % (113/1105) of the treated PVs. Among the 113 dissociated PV rhythms, 28 met the criteria of PVT with mean CL of (155±43) ms (2 PYTs in 2 patients received SPYA, 26 PYTs in 18 patients underwent CPVA). PVT was more frequently documented in patients underwent CPVA approach [9.0% (18/200) vs 2.3% (2/85), P=0.04]. During the 6-month follow-up, it was indicated that no significant difference existed in AF free rate between pa展开更多
Bone defects caused by trauma or tumor led to high medical costs and poor life quality for patients.The exosomes,micro vesicles of 30-150 nm in diameter,derived from macrophages manipulated bone regeneration.However,t...Bone defects caused by trauma or tumor led to high medical costs and poor life quality for patients.The exosomes,micro vesicles of 30-150 nm in diameter,derived from macrophages manipulated bone regeneration.However,the role of hydrogen sulfide(H2S)in the biogenesis and function of exosomes and its effects on bone regeneration remains elusive.In this study,we used H2S slow releasing donor GYY4137 to stimulate macrophages and found that H2S promoted the polarization of M2 macrophages to increase bone regeneration of MSCs in vitro and in vivo.Moreover,we developed the H2S pre-treated M2 macrophage exosomes and found these exosomes displayed significantly higher capacity to promote bone regeneration in calvarial bone defects by re-establishing the local immune microenvironment.Mechanically,H2S treatment altered the protein profile of exosomes derived from M2 macrophages.One of the significantly enriched exosomal proteins stimulated by H2S,moesin protein,facilitated the exosomes endocytosis into MSCs,leading to activated theβ-catenin signaling pathway to promote osteogenic differentiation of MSCs.In summary,H2S pretreated M2 exosomes promoted the bone regeneration of MSCs via facilitating exosomes uptake by MSCs and activateβ-catenin signaling pathway.This study not only provides new strategies for promoting bone regeneration,but also provides new insights for the effect and mechanism of exosomes internalization.展开更多
Activated carbon-supported mercuric chloride(HgCl2) is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalys...Activated carbon-supported mercuric chloride(HgCl2) is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides(CsxHgyCl(x+2y)) highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions.展开更多
We investigate the statistical nature of holographic gas, which may represent the quasi-particle excitations of a strongly correlated gravitational system. We find that the holographic entropy can be obtained by modif...We investigate the statistical nature of holographic gas, which may represent the quasi-particle excitations of a strongly correlated gravitational system. We find that the holographic entropy can be obtained by modifying degeneracy. We calculate thermodynamical quantities and investigate stability of the holographic gas. When applying to cosmology, we find that the holographic gas behaves as holographic dark energy, and the parameter c in holographic dark energy can be calculated from our model. Our model of holographic gas generally predicts c 〈 1, implying that the fate of our universe is phantom-like.展开更多
Pectins had been extracted from shaddock raw material with 0.01 mol·L^-1 HCI and with three enzymic preparations including cellulase from aspergillus oryzaei.β -glucosidase from almonds and protopectinases-T, a ...Pectins had been extracted from shaddock raw material with 0.01 mol·L^-1 HCI and with three enzymic preparations including cellulase from aspergillus oryzaei.β -glucosidase from almonds and protopectinases-T, a protopectin-solubilizing enzyme, which did not degrade polygalacturonic acid, The effects of enzymic and acid soluhilization of pectin from shaddock materials were compared, The yield of pectin preparations, degree of acetylation, gelling strength, molecular weight and viscosity were determined. Enzymic methods of extraction gave much bigger yields of pectic substances. Compared with the pectin extracted with hydrochloric acid, all the samples derived from shaddock raw material with enzymic preparations had a significant lower D-galacturonic acid content.展开更多
This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C cata...This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.展开更多
The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail...The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail. The results show that u sing 2% (mass fraction) hydroxamic acid HGS98 and 5% D 2EHPA as synergist, germanium is extracted (1 stage) over 99% in 5 min at phase ratio ( V o∶ V a) of 1∶5 from indium raffinate with original acidity. Then, using 2 mol·L -1 NH 4F as strip liquor, the stripping recovery is over 98% in 15 min at phase ratio of 1∶1. This process has the following advantages:easy to operate, high recovery and selectivity, and lower investment cost. It provides a new way to recover rare metal-germanium from metallurgical spent residues.展开更多
Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ab...Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with bradyarrhythmia.Methods:A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015.Under the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was mapped.Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)system.Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm.Areas surrounding the sinus node,AV node,and the phrenic nerve were avoided.Results:Thirteen patients completed the studies.Ablation was successfully performed in 12 patients and failed in one.The highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications.The vagal reaction was observed before the improvement of the sinus and AV node function.No complications occurred during the procedures.Patients were followed up for a mean of 13.0±5.9 months.During the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope.The heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.023;106.0±5.0 vs.90.0±12.0 ms,t=9.80,P=0展开更多
Perturbation method of boundary geometry(PMOBG) used in Lapiacian problems is dealt with and the three--term perturbation expression of distributed capacitance of a coaxial line with perturbed walls is obtained. As an...Perturbation method of boundary geometry(PMOBG) used in Lapiacian problems is dealt with and the three--term perturbation expression of distributed capacitance of a coaxial line with perturbed walls is obtained. As an example,four-order expression of distributed capacitance of a elliptic coaxial line with small eccentricity is given.展开更多
基金Funding for the present study from the National Basic Research Program of China(973 Program,No.2011CB710800)the Opening Foundation(2014)of Zhejiang Zanyu Technology Co.,Ltd
文摘The effect of the amount of precipitant ammonia on the Cu0/Cu+ratio of Cu/Si O2 prepared by the deposition–precipitation method is investigated. Species at different preparation stages, resulted from the amount of ammonia used, are identified by the XRD and FTIR techniques. Chrysocolla together with either copper nitrate hydroxide or copper hydroxide coexist in the uncalcined catalysts. Upon calcination, the latter two species are converted to Cu O particles while chrysocolla remains. Following reduction, Cu O is transformed to metallic Cu and chrysocolla is converted to Cu2 O. The value of Cu0/Cu+ratio can be evaluated using the peak areas in their TPR profiles. Hydrogenation of dimethyl oxalate(DMO) to ethylene glycol(EG) shows that the selectivity of EG depends on the Cu0/Cu+ratio. Catalyst prepared with the addition of ammonia solution at n(NH3)/n(Cu2+) = 0.9 for precipitation–deposition gains a more suitable Cu0/Cu+ratio upon reduction and thus has a higher selectivity for EG.
基金Supported by the National Natural Science Foundation of China,No.81174263National Science and Technology Major Project during the 12th Five-year Plan Period,No.2012ZX1005006+1 种基金Sanming Project of Medicine in Shenzhen,Guangdong Province,China,No.SZSM201612074and Science and Technology Planning Project of Guangdong Province,China,No.2017A020213016.
文摘BACKGROUND No guideline recommends antiviral therapy for hepatitis B e antigen(HBeAg)-positive chronic hepatitis B patients with persistently normal alanine aminotransferase levels and a high hepatitis B virus(HBV)DNA viral load.AIM To evaluate the feasibility and safety of a Chinese herbal formula as a therapeutic option for chronic HBV infection.METHODS In total,395 patients(30–65 years old)with confirmed HBeAg-positive chronic hepatitis B infection and persistently normal alanine aminotransferase were randomized to receive either Chinese herbal formula or placebo for 96 wk.Endpoints to evaluate therapeutic efficacy included:(1)HBV DNA levels decreased to less than 4 log10 IU/mL at weeks 48 and 96;and(2)HBeAg clearance and seroconversion rates at weeks 48 and 96.RESULTS HBV DNA levels≤4 log10 IU/mL were 10.05%at week 48 and 18.59%at week 96 in the treatment group.The HBeAg clearance and conversion rates were 8.54%and 8.04%at week 48 and 16.08%and 14.57%at week 96,respectively.However,HBV DNA levels≤4 log10 IU/mL were 2.55%and 2.55%at weeks 48 and 96,respectively,and the HBeAg clearance rates were 3.06%and 5.61%at weeks 48 and 96,respectively,in the control group.The quantitative hepatitis B surface antigen and HBeAg levels at baseline and changes during the treatment period as well as the alanine aminotransferase elevation at weeks 12 and 24 were strong predictors of HBeAg clearance.CONCLUSION High rates of HBV DNA reduction,HBeAg clearance and seroconversion could be achieved with Chinese herbal formula treatments,and the treatments were relatively safe for HBeAg-positive chronic hepatitis B-infected patients with persistently normal alanine aminotransferase.The ability of the compound to modulate host immune function probably contributed to this effect.
基金supported by National Natural Science Foundation of China(No.NSFC-20976164)National Basic Research Program of China(973 Program)(No.2011 CB710800)
文摘A series of diphenyl-sulfide (Ph2S)-immobilized Pd/C catalysts (Pd-Ph2Scx)/C) were prepared using the wetness-impregnation and immobilization method. Pd-Ph2S(x)/C catalysts employed for the hydro- genation of o-chloronitrobenzene showed very high selectivity. The structure of Pd-Ph2Scx)/C with different molar ratio of ligand (x-values) was characterized by XPS and TG-DSC-MS. The results suggest a "saturated" surface ratio of Ph2S/Pd (about 0.3) was formed on the Pd-Ph2S(x)[C catalysts surface. The Ph2S immobilized on the Pd particle is quite stable, and the desorption of Ph2S or dissociative loss of phenyl group was only found at temperatures above 500 K. The possible catalytic mechanism of the Pd-Ph2S(x)/C catalyst was also discussed.
基金Supported by Sanming Project of Medicine in Shenzhen of China,No.SZSM201612074
文摘BACKGROUND Progressive familial intrahepatic cholestasis(PFIC)encompasses a group of autosomal recessive disorders with high morbidity and mortality.Variants in the gene encoding tight junction protein-2(TJP2)have been linked to PFIC type 4(PFIC4),which predominantly presents in childhood.However,there are only limited data from adults with TJP2-related PFIC4.We report a family with an autosomal recessive disorder with a novel variant in the TJP2 gene in adults with very variable expression of PFIC4.CASE SUMMARY The index patient presented at 19 years old with liver cirrhosis and variceal bleeding and was treated with endoscopic banding and beta-blockers.In 2018,he developed primary liver cancer that was treated with radiofrequency ablation followed by liver transplantation in 2019.Genetic testing revealed a novel homozygous TJP2 variant causing PFIC4(TJP2([NM_004817.3]:c.[3334C>T];[3334C>T])).The consanguineous family consists of the father and mother(both heterozygous)and their 12 children,of which five carry the variant in a homozygous state;however,these five siblings have highly variable expression of PFIC4.Two homozygous brothers had cirrhosis and portal hypertension at diagnosis at the ages of 19 and 36.Two other homozygous brothers,age 23 and 19,and the homozygous sister,age 21,have elevated liver enzymes but presently no cirrhosis,which may suggest an age-dependent penetrance.In addition,five sisters had severe and mild intrahepatic cholestasis of pregnancy and carry the TJP2 variant in a homozygous and heterozygous state,respectively.CONCLUSION This novel TJP2 variant is associated with PFIC4 causing severe liver disease with cirrhosis and primary liver cancer in adolescents/adults.
基金National Natural Science Foundation of China,No.81174263Sanming Project of Medicine in Shenzhen,Guangdong Province,China,No.SZSM201612074Shenzhen Science and Technology Project,Guangdong Province,China,No.201202154.
文摘BACKGROUND China has a high prevalence of hepatitis B virus(HBV),but most chronic hepatitis B(CHB)patients do not receive standardized antiviral therapy.There are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral therapy.AIM To observe the outcomes of long-term follow-up of patients with CHB without antiviral treatment.METHODS This study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to 1998.The median follow-up times were 10 and 7 years,respectively.A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control groups.The median follow-up times were 8 and 7 years,respectively.Kaplan-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma(HCC),and the Cox regression model was used to analyze the risk factors for HCC.RESULTS Among the patients in the non-antiviral group,16.9%had spontaneous decreases(HBeAg)seroconversion.In the antiviral group,87.2%of patients had undetectable HBV DNA,and 52%showed HBeAg seroconversion.Among CHB and hepatitis B cirrhosis patients,the cumulative incidence rates of HCC were 14.9%and 53.1%,respectively,in the non-antiviral group and were 10.7%and 31.9%,respectively,in the antiviral group.There was no difference between the two groups regarding the CHB patients(P=0.842),but there was a difference between the groups regarding the hepatitis B cirrhosis patients(P=0.026).The cumulative incidence rates of HCC were 1.6%and 22.3%(P=0.022)in the groups with and without spontaneous HBeAg seroconversion,respectively.The incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6%and 19.1%,respectively(P=0.051).There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistant CHB(P=0.119),but there was a significant diffe
基金This study was supported by a grant from the "Tenth Five" Research Project of China (No. 2004BA714B04).
文摘Background Pulmonary vein (PV) isolation has been developed to treat patients with atrial fibrillation (AF), and the electrophysiological endpoint of PV isolation is the disappearance or dissociation of pulmonary vein potentials (PVPs). Pulmonary vein tachycardia (PVT) is the dissociated PV rhythm with a rapid rate. However, the characteristics and significance of PVT after pulmonary vein isolation in patients with AF remains unclear. Methods From June 2003 to June 2005, a total of 285 consecutive patients with drug refractory AF were included in this study, and they underwent segmental pulmonary vein ablation (SPVA) or circumferential pulmonary vein ablation (CPVA). PV isolation was the initial endpoint for both approaches with documenting disappearance or dissociation of PVPs. PVT was characterized as dissociated activities within PVs with a circle length (CL) of 〈300 ms, and was classified into organized PVT or disorganized PVT according to the variance of CL. Systematic follow-up was conducted after initial procedures. Continuous variables were analyzed by Student's t test and categorical variables were analyzed by chi-square test. Results Three hundred and fifteen PVs were ablated in 85 patients underwent SPVA approach, 400 circular lesions surrounding ipsilateral PVs (including 790 PVs) were produced in the rest of 200 patients received CPVA approach. Electrical isolation was achieved in all of these PVs. Of these, PVPs were abolished in 89.8% (992/1105) of the ablated PVs, dissociated PV rhythms were documented in the rest 10.2 % (113/1105) of the treated PVs. Among the 113 dissociated PV rhythms, 28 met the criteria of PVT with mean CL of (155±43) ms (2 PYTs in 2 patients received SPYA, 26 PYTs in 18 patients underwent CPVA). PVT was more frequently documented in patients underwent CPVA approach [9.0% (18/200) vs 2.3% (2/85), P=0.04]. During the 6-month follow-up, it was indicated that no significant difference existed in AF free rate between pa
基金supported by the National Science and Technology Major Project of the Ministry of Science and Technology of China No.2022YFA1105800the National Natural Science Foundation of China No.81970940(R.Y)Ten-thousand Talents Program QNBJ-2020(R.Y).
文摘Bone defects caused by trauma or tumor led to high medical costs and poor life quality for patients.The exosomes,micro vesicles of 30-150 nm in diameter,derived from macrophages manipulated bone regeneration.However,the role of hydrogen sulfide(H2S)in the biogenesis and function of exosomes and its effects on bone regeneration remains elusive.In this study,we used H2S slow releasing donor GYY4137 to stimulate macrophages and found that H2S promoted the polarization of M2 macrophages to increase bone regeneration of MSCs in vitro and in vivo.Moreover,we developed the H2S pre-treated M2 macrophage exosomes and found these exosomes displayed significantly higher capacity to promote bone regeneration in calvarial bone defects by re-establishing the local immune microenvironment.Mechanically,H2S treatment altered the protein profile of exosomes derived from M2 macrophages.One of the significantly enriched exosomal proteins stimulated by H2S,moesin protein,facilitated the exosomes endocytosis into MSCs,leading to activated theβ-catenin signaling pathway to promote osteogenic differentiation of MSCs.In summary,H2S pretreated M2 exosomes promoted the bone regeneration of MSCs via facilitating exosomes uptake by MSCs and activateβ-catenin signaling pathway.This study not only provides new strategies for promoting bone regeneration,but also provides new insights for the effect and mechanism of exosomes internalization.
文摘Activated carbon-supported mercuric chloride(HgCl2) is used as an industrial catalyst for acetylene hydrochlorination. However, the characteristic of easy sublimation of HgCl2 leads to the deactivation o the catalyst. Here, we showed that the thermal stability of the Hg/AC catalyst can be evidently improved when Cs Cl is added into the Hg/AC catalyst. Compared with the pure Hg/AC catalyst, the sublimation rate of HgCl2 from the Hg–Cs/AC catalyst decreased significantly and the Hg–Cs/AC catalyst showed bette catalytic activity and stability in the reaction. This promoting effect is related to the existence of cesium mercuric chlorides(CsxHgyCl(x+2y)) highlighted by XRD, HR-TEM and EDX analyses. Thus, reacting HgCl2 with alkali chlorides to form alkali-mercuric chlorides may be a key to design highly efficient and thermally stable mercuric chloride catalyst for hydrochlorination reactions.
基金supported by National Natural Science Foundation of China under Grant No. 10525050a "973" Project under Grant No. 2007CB815401
文摘We investigate the statistical nature of holographic gas, which may represent the quasi-particle excitations of a strongly correlated gravitational system. We find that the holographic entropy can be obtained by modifying degeneracy. We calculate thermodynamical quantities and investigate stability of the holographic gas. When applying to cosmology, we find that the holographic gas behaves as holographic dark energy, and the parameter c in holographic dark energy can be calculated from our model. Our model of holographic gas generally predicts c 〈 1, implying that the fate of our universe is phantom-like.
基金The Key Program of Science and Technology Office of Hunan Province (00KNY1010)
文摘Pectins had been extracted from shaddock raw material with 0.01 mol·L^-1 HCI and with three enzymic preparations including cellulase from aspergillus oryzaei.β -glucosidase from almonds and protopectinases-T, a protopectin-solubilizing enzyme, which did not degrade polygalacturonic acid, The effects of enzymic and acid soluhilization of pectin from shaddock materials were compared, The yield of pectin preparations, degree of acetylation, gelling strength, molecular weight and viscosity were determined. Enzymic methods of extraction gave much bigger yields of pectic substances. Compared with the pectin extracted with hydrochloric acid, all the samples derived from shaddock raw material with enzymic preparations had a significant lower D-galacturonic acid content.
基金supported by the National Natural Science Foundation of China(Nos.20976164,21176221 and 21136001)National Basic Research Program of China(973 Program)(Nos. 2011CB710803,2013CB733500)Zhejiang Provincial Natural Science Foundation of China(No.LY12B03005)
文摘This study shows that minor amount of water plays a very important role in solvent-free hydrogenation of halogenated nitrobenzenes. For dried sponge Pd, the reaction cannot occur in the absence of water. For Pd/C catalyst, minor amount of water reduces the induction time, increases the reaction rate and reaction TOFs. Water might enhance the diffusion, adsorption and dissociation of H2 on Pd catalysts.
文摘The extraction separation of germanium from indium raffinate in hydrometallurgical zinc process was discussed. The conditions and mechanism of the extraction with hydroxamic acid HGS98 have been investigated in detail. The results show that u sing 2% (mass fraction) hydroxamic acid HGS98 and 5% D 2EHPA as synergist, germanium is extracted (1 stage) over 99% in 5 min at phase ratio ( V o∶ V a) of 1∶5 from indium raffinate with original acidity. Then, using 2 mol·L -1 NH 4F as strip liquor, the stripping recovery is over 98% in 15 min at phase ratio of 1∶1. This process has the following advantages:easy to operate, high recovery and selectivity, and lower investment cost. It provides a new way to recover rare metal-germanium from metallurgical spent residues.
文摘Background:The symptomatic bradyarrhythmia is Class I indication for pacing therapy which is not a radical cure.The present study aimed to assess the feasibility and to present the initial results of the restricted ablation of the parasympathetic innervation surrounding sinus and atrioventricular(AV)nodes for treating patients with bradyarrhythmia.Methods:A total of 13 patients with cardiogenic syncope were included from May 2008 to June 2015.Under the guidance of fluoroscopy and/or three-dimensional geometry by 64-slice spiral computed tomography,atrial activation sequence in sinus rhythm was mapped.Chamber geometry was reconstructed manually or automatically using the Niobe II magnetic navigation system integrated with the CARTO-remote magnetic technology(RMT)system.Cardioneuroablation was targeted at the high-amplitude fractionated electrograms surrounding the regions of His bundle and the site with the earliest activation in sinus rhythm.Areas surrounding the sinus node,AV node,and the phrenic nerve were avoided.Results:Thirteen patients completed the studies.Ablation was successfully performed in 12 patients and failed in one.The highfrequency potential was recorded in atrial electrograms surrounding the sinus or AV nodes in all the patients and disappeared in 15 s after radiofrequency applications.The vagal reaction was observed before the improvement of the sinus and AV node function.No complications occurred during the procedures.Patients were followed up for a mean of 13.0±5.9 months.During the follow up ten patients remained free of symptoms,and two patients had a permanent cardiac pacemaker implanted due to spontaneous recurrence of syncope.The heart rate of post-ablation was higher than pre-ablation(69.0±11.0 vs.49.0±10.0 beats/min,t=4.56,P=0.008).The sinus node recovery time,Wenckebach block point,and atrium-His bundle interval were significantly shorter after ablation(1386.0±165.0 vs.921.0±64.0 ms,t=7.45,P=0.002;590.0±96.0 vs.464.0±39.0 ms,t=2.38,P=0.023;106.0±5.0 vs.90.0±12.0 ms,t=9.80,P=0
基金the Open Foundation of State Key Laboratory of Advanced Technology for Materials Synthersis Processing
文摘Perturbation method of boundary geometry(PMOBG) used in Lapiacian problems is dealt with and the three--term perturbation expression of distributed capacitance of a coaxial line with perturbed walls is obtained. As an example,four-order expression of distributed capacitance of a elliptic coaxial line with small eccentricity is given.