Particulate matter with diameters of 2.5 μm or smaller(PM_(2.5)) and ozone(O_3) are major pollutants in the urban atmosphere. PM_(2.5) can affect O_3 by altering the photolysis rate and heterogeneous reactions. Howev...Particulate matter with diameters of 2.5 μm or smaller(PM_(2.5)) and ozone(O_3) are major pollutants in the urban atmosphere. PM_(2.5) can affect O_3 by altering the photolysis rate and heterogeneous reactions. However, these two processes and their relative importance remain uncertain. In this paper, with Nanjing in China as the target city, we investigate the characteristics and mechanism of interactions between particles and O_3 based on ground observations and numerical modeling.In 2008, the average concentrations of PM_(2.5) and O_3 at Caochangmen station are 64.6 ± 47.4 μg m^(-3) and 24.6 ± 22.8 ppb,respectively, while at Pukou station they are 94.1 ± 63.4 μg m^(-3) and 16.9 ± 14.9 ppb. The correlation coefficient between PM_(2.5) and O_3 is -0.46. In order to understand the reaction between PM_(2.5) and O_3, we construct a box model, in which an aerosol optical property model, ultraviolet radiation model, gas phase chemistry model, and heterogeneous chemistry model,are coupled. The model is employed to investigate the relative contribution of the aforementioned two processes, which vary under different particle concentrations, scattering capability and VOCs/NOxratios(VOCs: volatile organic compounds;NOx: nitric oxide and nitrogen dioxide). Generally, photolysis rate effect can cause a greater O_3 reduction when the particle concentrations are higher, while heterogeneous reactions dominate O_3 reduction with low-level particle concentrations.Moreover, in typical VOC-sensitive regions, O_3 can even be increased by heterogeneous reactions. In Nanjing, both processes lead to O_3 reduction, and photolysis rate effect is dominant. Our study underscores the importance of photolysis rate effect and heterogeneous reactions for O_3, and such interaction processes should be fully considered in future atmospheric chemistry modeling.展开更多
Cholellthiasis is a kind of common and multiple diseases. In recent years, traolttonal laparommy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and comp...Cholellthiasis is a kind of common and multiple diseases. In recent years, traolttonal laparommy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and complications of minimally invasive treatment of intrahepatic and extrahepatic bile duct stones by combining our practical experience were summarized as follows. （1） For intrahepatic bile duct stones, the operation may be selected by laparoscopie liver resection, laparoscopic common bile duct exploration （LCBDE）, or percutaneous transhepatic cholangioscopy. （2） For concomitant gallstones and common bile duct stones, the surgical approach can be selected as follows： laparoscopic cholecystectomy （LC） combined with endoscopic sphincterotomy （EST） or endoscopic papillary balloon dilatation, LC plus laparoscopic transcystic common bile duct exploration, LC plus LCBDE, and T-tube drainage or primary suture. （3） For concomitant intrahepatic and extrahepatic bile duct stones, laparoscopic liver resection, choledochoscopy through the hepatic duct orifice on the hepatectomy cross section, LCBDE, EST, and percutaneous transhepatic cholangioscopic lithotripsy could be used. According to the abovementioned principle, the minimally invasive treatment approach combined with the surgical technique and equipment condition will be significant in improving the therapeutic effect and avoiding the postoperative complications or hidden dangers of intrahepatic and extrahepatic bile duct stones.展开更多
目的研究维生素K联合骨化三醇、钙尔奇D对男性骨质疏松的治疗效果及对骨代谢的影响。方法采用美国Hologic公司生产的Discovery WA型双能X线骨密度仪检测患者腰椎L1~4骨密度(bone mineral density,BMD)与股骨颈骨密度。对男性骨质疏松患...目的研究维生素K联合骨化三醇、钙尔奇D对男性骨质疏松的治疗效果及对骨代谢的影响。方法采用美国Hologic公司生产的Discovery WA型双能X线骨密度仪检测患者腰椎L1~4骨密度(bone mineral density,BMD)与股骨颈骨密度。对男性骨质疏松患者采用固力康联合骨化三醇、碳酸钙D3进行治疗,连续治疗1年,治疗期间监测患者骨代谢变化。采用美国Thermo公司全自动酶标免疫分析仪检测患者血清骨代谢指标BGP、CTX-1、细胞因子IL-6、IL-10水平。结果治疗6个月后患者腰椎(L1-4) BMD、股骨颈BMD开始增加,治疗12个月后患者腰椎(L1-4) BMD、股骨颈BMD较治疗前增加明显。治疗后,血清骨形成指标BGP水平升高、细胞因子IL-10水平升高;血清骨吸收指标CTX-1水平、细胞因子IL-6水平降低。结论维生素K可提高患者腰椎与股骨颈骨密度,升高血清骨形成指标BGP、细胞因子IL-10水平,降低血清骨吸收指标CTX-1、细胞因子IL-6水平,维生素K治疗男性骨质疏松效果显著,是临床上治疗骨质疏松的重要策略之一。展开更多
Brassinosteroid （BR） binding activates the receptor kinase BRI1 by inducing heterodimerization with its co- receptor kinase BAK1; however, the mechanisms that reversibly inactivate BRI1 remain unclear. Here we show ...Brassinosteroid （BR） binding activates the receptor kinase BRI1 by inducing heterodimerization with its co- receptor kinase BAK1; however, the mechanisms that reversibly inactivate BRI1 remain unclear. Here we show that cytoplasm-localized protein phosphatase 2A （PP2A） B＇ regulatory subunits interact with BRI1 to mediate its dephosphorylation and inactivation. Loss-of-function and overexpression experiments showed that a group of PP2A B＇ regulatory subunits, represented by B＇η, negatively regulate BR signaling by decreasing BRI1 phosphorylation. BR increases the expression levels of these B＇ subunits, and B/TI interacts preferentially with phosphorylated BRI1, suggesting that the dynamics of BR signaling are modu- lated by the PP2A-mediated feedback inactivation of BRI1. Compared with PP2A B＇α and B＇β, which promote BR responses by dephosphorylating the downstream transcription factor BZR1, the BRI1- inactivating B＇ subunits showed similar binding to BRI1 and BZR1 but distinct subcellular localization. Alteration of the nuclear/cytoplasmic localization of the B＇ subunits revealed that cytoplasmic PP2A de- phosphorylates BRI1 and inhibits the BR response, whereas nuclear PP2A dephosphorylates BZR1 and ac- tivates the BR response. Our findings not only identify the PP2A regulatory B subunits that mediate the binding and dephosphorylation of BRI1, but also demonstrate that the subcellular localization of PP2A specifies its substrate selection and distinct effects on BR signaling.展开更多
基金supported by the National Key Basic Research & Development Program of China (Grant Nos. 2016YFC0203303, 2016YFC0208504 and 2014CB441203)the National Natural Science Foundation of China (Grant Nos. 91544230, 41575145 and 41621005)the EU 7th Framework Marie Curie Actions IRSES project: REQUA (Grant No. PIRSESGA-2013-612671)
文摘Particulate matter with diameters of 2.5 μm or smaller(PM_(2.5)) and ozone(O_3) are major pollutants in the urban atmosphere. PM_(2.5) can affect O_3 by altering the photolysis rate and heterogeneous reactions. However, these two processes and their relative importance remain uncertain. In this paper, with Nanjing in China as the target city, we investigate the characteristics and mechanism of interactions between particles and O_3 based on ground observations and numerical modeling.In 2008, the average concentrations of PM_(2.5) and O_3 at Caochangmen station are 64.6 ± 47.4 μg m^(-3) and 24.6 ± 22.8 ppb,respectively, while at Pukou station they are 94.1 ± 63.4 μg m^(-3) and 16.9 ± 14.9 ppb. The correlation coefficient between PM_(2.5) and O_3 is -0.46. In order to understand the reaction between PM_(2.5) and O_3, we construct a box model, in which an aerosol optical property model, ultraviolet radiation model, gas phase chemistry model, and heterogeneous chemistry model,are coupled. The model is employed to investigate the relative contribution of the aforementioned two processes, which vary under different particle concentrations, scattering capability and VOCs/NOxratios(VOCs: volatile organic compounds;NOx: nitric oxide and nitrogen dioxide). Generally, photolysis rate effect can cause a greater O_3 reduction when the particle concentrations are higher, while heterogeneous reactions dominate O_3 reduction with low-level particle concentrations.Moreover, in typical VOC-sensitive regions, O_3 can even be increased by heterogeneous reactions. In Nanjing, both processes lead to O_3 reduction, and photolysis rate effect is dominant. Our study underscores the importance of photolysis rate effect and heterogeneous reactions for O_3, and such interaction processes should be fully considered in future atmospheric chemistry modeling.
文摘Cholellthiasis is a kind of common and multiple diseases. In recent years, traolttonal laparommy has been challenged by a minimally invasive surgery. Through literature review, the therapeutic method, effect, and complications of minimally invasive treatment of intrahepatic and extrahepatic bile duct stones by combining our practical experience were summarized as follows. （1） For intrahepatic bile duct stones, the operation may be selected by laparoscopie liver resection, laparoscopic common bile duct exploration （LCBDE）, or percutaneous transhepatic cholangioscopy. （2） For concomitant gallstones and common bile duct stones, the surgical approach can be selected as follows： laparoscopic cholecystectomy （LC） combined with endoscopic sphincterotomy （EST） or endoscopic papillary balloon dilatation, LC plus laparoscopic transcystic common bile duct exploration, LC plus LCBDE, and T-tube drainage or primary suture. （3） For concomitant intrahepatic and extrahepatic bile duct stones, laparoscopic liver resection, choledochoscopy through the hepatic duct orifice on the hepatectomy cross section, LCBDE, EST, and percutaneous transhepatic cholangioscopic lithotripsy could be used. According to the abovementioned principle, the minimally invasive treatment approach combined with the surgical technique and equipment condition will be significant in improving the therapeutic effect and avoiding the postoperative complications or hidden dangers of intrahepatic and extrahepatic bile duct stones.
文摘Brassinosteroid （BR） binding activates the receptor kinase BRI1 by inducing heterodimerization with its co- receptor kinase BAK1; however, the mechanisms that reversibly inactivate BRI1 remain unclear. Here we show that cytoplasm-localized protein phosphatase 2A （PP2A） B＇ regulatory subunits interact with BRI1 to mediate its dephosphorylation and inactivation. Loss-of-function and overexpression experiments showed that a group of PP2A B＇ regulatory subunits, represented by B＇η, negatively regulate BR signaling by decreasing BRI1 phosphorylation. BR increases the expression levels of these B＇ subunits, and B/TI interacts preferentially with phosphorylated BRI1, suggesting that the dynamics of BR signaling are modu- lated by the PP2A-mediated feedback inactivation of BRI1. Compared with PP2A B＇α and B＇β, which promote BR responses by dephosphorylating the downstream transcription factor BZR1, the BRI1- inactivating B＇ subunits showed similar binding to BRI1 and BZR1 but distinct subcellular localization. Alteration of the nuclear/cytoplasmic localization of the B＇ subunits revealed that cytoplasmic PP2A de- phosphorylates BRI1 and inhibits the BR response, whereas nuclear PP2A dephosphorylates BZR1 and ac- tivates the BR response. Our findings not only identify the PP2A regulatory B subunits that mediate the binding and dephosphorylation of BRI1, but also demonstrate that the subcellular localization of PP2A specifies its substrate selection and distinct effects on BR signaling.
