有机化学是药学专业非常重要又较难学习的一门专业基础课,认识有机化合物的结构是学好这门课程的基础,单纯平面教学无法深入地将分子的实际空间结构加以充分展示。通过在有机化学实验课中开设球棍模型搭建及Chem Bio Office软件应用这...有机化学是药学专业非常重要又较难学习的一门专业基础课,认识有机化合物的结构是学好这门课程的基础,单纯平面教学无法深入地将分子的实际空间结构加以充分展示。通过在有机化学实验课中开设球棍模型搭建及Chem Bio Office软件应用这一内容,利用立体、形象的原子间的相对位置,可以促进学生迅速地理解、掌握化合物的立体结构,把握有机分子构成的基本方式,为后续的教学内容打下良好的基础。展开更多
Histone methylation is a context-dependent modification that regulates gene expression,and the trimethylation of histone H3 lysine 27(H3K27me3)usually induces gene silencing.Overcoming colorectal cancer(CRC)chemoresis...Histone methylation is a context-dependent modification that regulates gene expression,and the trimethylation of histone H3 lysine 27(H3K27me3)usually induces gene silencing.Overcoming colorectal cancer(CRC)chemoresistance is currently a huge challenge,but the relationship between H3K27me3 modification and chemoresistance remains largely unclear.Here,we found that H3K27me3 levels positively correlated with the metastasis-free survival of CRC patients and a low H3K27me3 level predicted a poor outcome upon chemotherapeutic drug treatment.Oxaliplatin stimulation significantly induced the expression of H3K27 lysine demethylase 6A/6B(KDM6A/6B),thus decreasing the level of H3K27me3 in CRC cells.Elevation of H3K27me3 level through KDM6A/6B depletion or GSK-J4(a KDM6A/6B inhibitor)treatment significantly enhanced oxaliplatin-induced apoptosis.Conversely,when inhibiting the expression of H3K27me3 by EPZ-6438,an inhibitor of the histone methyltransferase EZH2,the proportion of apoptotic cells remarkably decreased.In addition,the combination of GSK-J4 and oxaliplatin significantly inhibited tumor growth in an oxaliplatin-resistant patient-derived xenograft model.Importantly,we revealed that oxaliplatin treatment dramatically induced NOTCH2 expression,which was caused by downregulation of H3K27me3 level on the NOTCH2 transcription initiation site.Thus,the activated NOTCH signaling promoted the expression of stemness-related genes,which resulted in oxaliplatin resistance.Furthermore,oxaliplatin-induced NOTCH signaling could be interrupted by GSK-J4 treatment.Collectively,our findings suggest that elevating H3K27me3 level can improve drug sensitivity in CRC patients.展开更多
The North China Plain often su ers heavy haze pollution events in the cold season due to the rapid industrial development and urbanization in recent decades.In the winter of 2015,the megacity cluster of Beijing Tianji...The North China Plain often su ers heavy haze pollution events in the cold season due to the rapid industrial development and urbanization in recent decades.In the winter of 2015,the megacity cluster of Beijing Tianjin Hebei experienced a seven-day extreme haze pollution episode with peak PM2.5(particulate matter(PM)with an aerodynamic diameter≤2.5μm)concentration of 727μg m 3.Considering the in uence of meteorological conditions on pollu-tant evolution,the e ects of varying initial conditions and lateral boundary conditions(LBCs)of the WRF-Chem model on PM2.5 concentration variation were investigated through ensemble methods.A control run(CTRL)and three groups of ensemble experiments(INDE,BDDE,INBDDE)were carried out based on difierent initial conditions and LBCs derived from ERA5 reanalysis data and its 10 ensemble members.The CTRL run reproduced the meteorological conditions and the overall life cycle of the haze event reasonably well,but failed to capture the intense oscillation of the instantaneous PM2.5 concentration.However,the ensemble forecasting showed a considerable advantage to some extent.Compared with the CTRL run,the root-mean-square error(RMSE)of PM2.5 concentration decreased by 4.33%,6.91%,and 8.44%in INDE,BDDE and INBDDE,respectively,and the RMSE decreases of wind direction(5.19%,8.89%and 9.61%)were the dominant reason for the improvement of PM2.5 concentration in the three ensemble experiments.Based on this case,the ensemble scheme seems an e ective method to improve the prediction skill of wind direction and PM2.5 concentration by using the WRF-Chem model.展开更多
Poly-crystalline silicon thin film has big potential of reducing the cost of solar cells. In this paper the preparation of thin film is introduced, and then the morphology of poly-crystalline thin film, is discussed. ...Poly-crystalline silicon thin film has big potential of reducing the cost of solar cells. In this paper the preparation of thin film is introduced, and then the morphology of poly-crystalline thin film, is discussed. On the film we developed poly-crystalline silicon thin film solar cells with efficiency up to 6.05% without anti-reflection coating.展开更多
The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o g...The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o groups, 871 usinig PAP and 834 w om en using PM. Results: Thefeverratesw ere8.0and 4.4( P< 0.01 ) respec- tively in group PAP and group PM. Infection rates of the appendages w ere 2.3 and 1.2 respectively. The incidence of chem ical peritonitis, w ithin the lim its of pelvic cavity, w ere 1.1and 2.4respectively. Perforation of uterus, pelvic ab- scessand ectopicpregnancy w ere notfound during thisobservation. Slightabdom inal pain after the proceduresw ere 33.6and 30.8respectively. Slightvaginalbleed- ing after the procedure w as 23.2 and 18.0 respectively. Menstruation of the w om en w as not affected by the instillation. This five-year follow -up study neither show ed a positivePap testnor a potentialdeseasecaused by thesterilizing agents. This technique isa safe and efficientm ethod for fem ale sterilization.展开更多
文摘学习进阶的研究在近十几年来成为国际科学教育领域的研究热点,其促进了科学教育研究方法的丰富和完善。典型的学习进阶开发模式有伯克利系统、结构中心设计法和ChemQuery评价系统。其中Chem Query评价系统是最具学科特色的学习进阶开发模式。它以化学学科中核心概念,即化学家观念(Perspectives of Chemists)为框架,运用项目反应理论进行标准参照分析,描述和测量学生化学核心概念理解的发展进阶。Chem Query评价系统的修正过程,其本身就是化学学科理解的学习进阶开发过程。这一开发模式是科学教育中核心概念研究领域值得借鉴的模式和思路。
文摘有机化学是药学专业非常重要又较难学习的一门专业基础课,认识有机化合物的结构是学好这门课程的基础,单纯平面教学无法深入地将分子的实际空间结构加以充分展示。通过在有机化学实验课中开设球棍模型搭建及Chem Bio Office软件应用这一内容,利用立体、形象的原子间的相对位置,可以促进学生迅速地理解、掌握化合物的立体结构,把握有机分子构成的基本方式,为后续的教学内容打下良好的基础。
基金This work was supported by the National Program on Key Research(2018YFA0107500 and 2016YFC1302400)the National Natural Science Foundation of China(91742113 and 31570902)Natural Science Foundation of Shanghai(14ZR14-26300,18ZR1424400,18ZR1446400,and 18431902700).
文摘Histone methylation is a context-dependent modification that regulates gene expression,and the trimethylation of histone H3 lysine 27(H3K27me3)usually induces gene silencing.Overcoming colorectal cancer(CRC)chemoresistance is currently a huge challenge,but the relationship between H3K27me3 modification and chemoresistance remains largely unclear.Here,we found that H3K27me3 levels positively correlated with the metastasis-free survival of CRC patients and a low H3K27me3 level predicted a poor outcome upon chemotherapeutic drug treatment.Oxaliplatin stimulation significantly induced the expression of H3K27 lysine demethylase 6A/6B(KDM6A/6B),thus decreasing the level of H3K27me3 in CRC cells.Elevation of H3K27me3 level through KDM6A/6B depletion or GSK-J4(a KDM6A/6B inhibitor)treatment significantly enhanced oxaliplatin-induced apoptosis.Conversely,when inhibiting the expression of H3K27me3 by EPZ-6438,an inhibitor of the histone methyltransferase EZH2,the proportion of apoptotic cells remarkably decreased.In addition,the combination of GSK-J4 and oxaliplatin significantly inhibited tumor growth in an oxaliplatin-resistant patient-derived xenograft model.Importantly,we revealed that oxaliplatin treatment dramatically induced NOTCH2 expression,which was caused by downregulation of H3K27me3 level on the NOTCH2 transcription initiation site.Thus,the activated NOTCH signaling promoted the expression of stemness-related genes,which resulted in oxaliplatin resistance.Furthermore,oxaliplatin-induced NOTCH signaling could be interrupted by GSK-J4 treatment.Collectively,our findings suggest that elevating H3K27me3 level can improve drug sensitivity in CRC patients.
基金supported by the National Basic Research(973)Program of China [grant number2015CB954102]the National Natural Science Foundation of China [grant number 41475043]the National Key R&D Program of China [grant number 2018YFC1507403]
文摘The North China Plain often su ers heavy haze pollution events in the cold season due to the rapid industrial development and urbanization in recent decades.In the winter of 2015,the megacity cluster of Beijing Tianjin Hebei experienced a seven-day extreme haze pollution episode with peak PM2.5(particulate matter(PM)with an aerodynamic diameter≤2.5μm)concentration of 727μg m 3.Considering the in uence of meteorological conditions on pollu-tant evolution,the e ects of varying initial conditions and lateral boundary conditions(LBCs)of the WRF-Chem model on PM2.5 concentration variation were investigated through ensemble methods.A control run(CTRL)and three groups of ensemble experiments(INDE,BDDE,INBDDE)were carried out based on difierent initial conditions and LBCs derived from ERA5 reanalysis data and its 10 ensemble members.The CTRL run reproduced the meteorological conditions and the overall life cycle of the haze event reasonably well,but failed to capture the intense oscillation of the instantaneous PM2.5 concentration.However,the ensemble forecasting showed a considerable advantage to some extent.Compared with the CTRL run,the root-mean-square error(RMSE)of PM2.5 concentration decreased by 4.33%,6.91%,and 8.44%in INDE,BDDE and INBDDE,respectively,and the RMSE decreases of wind direction(5.19%,8.89%and 9.61%)were the dominant reason for the improvement of PM2.5 concentration in the three ensemble experiments.Based on this case,the ensemble scheme seems an e ective method to improve the prediction skill of wind direction and PM2.5 concentration by using the WRF-Chem model.
基金This work was supported by the Chinese Academy of Sciences within the Hundred Talent Project(No.99-019-422288)National High Technical Research and Development Programme of China(No.2001AA513060).
文摘Poly-crystalline silicon thin film has big potential of reducing the cost of solar cells. In this paper the preparation of thin film is introduced, and then the morphology of poly-crystalline thin film, is discussed. On the film we developed poly-crystalline silicon thin film solar cells with efficiency up to 6.05% without anti-reflection coating.
文摘The present objective is to observe the side effects and complications of fem ale tubalsterilization by phenol-atabrinepaste (PAP) and phenolm ucilage (PM). 1 705 eligible w om en w ere divided random ly into tw o groups, 871 usinig PAP and 834 w om en using PM. Results: Thefeverratesw ere8.0and 4.4( P< 0.01 ) respec- tively in group PAP and group PM. Infection rates of the appendages w ere 2.3 and 1.2 respectively. The incidence of chem ical peritonitis, w ithin the lim its of pelvic cavity, w ere 1.1and 2.4respectively. Perforation of uterus, pelvic ab- scessand ectopicpregnancy w ere notfound during thisobservation. Slightabdom inal pain after the proceduresw ere 33.6and 30.8respectively. Slightvaginalbleed- ing after the procedure w as 23.2 and 18.0 respectively. Menstruation of the w om en w as not affected by the instillation. This five-year follow -up study neither show ed a positivePap testnor a potentialdeseasecaused by thesterilizing agents. This technique isa safe and efficientm ethod for fem ale sterilization.
