以质膜 Ca2 +通道阻断剂 L a Cl3和钙调素 (Ca M)拮抗剂氯丙嗪 (CPZ)对水稻幼苗预处理以阻碍 Ca2 +· Ca M信使传导后 ,研究了盐胁迫下 ,稻苗保护酶活性的变化。结果表明 :0 .15 mol/ L Na Cl胁迫下 ,L a Cl3和 CPZ预处理显著加剧...以质膜 Ca2 +通道阻断剂 L a Cl3和钙调素 (Ca M)拮抗剂氯丙嗪 (CPZ)对水稻幼苗预处理以阻碍 Ca2 +· Ca M信使传导后 ,研究了盐胁迫下 ,稻苗保护酶活性的变化。结果表明 :0 .15 mol/ L Na Cl胁迫下 ,L a Cl3和 CPZ预处理显著加剧稻苗过氧化氢酶 (CAT)活性和抗坏血酸过氧化物酶 (APX)活性下降 ;对谷胱甘肽还原酶 (GR)活性则无明显影响 ;而超氧化物岐化酶 (SOD)和过氧化物酶 (POD)活性前期无明显变化 ,仅在胁迫后期明显下降。盐胁迫下 ,L a Cl3和 CPZ预处理加剧 SOD、 CAT和 APX活性下降与加剧稻苗 MDA含量积累呈显著或极显著正相关。这暗示 Ca2 + · Ca展开更多
Dissolutionof La in KCl-NaCl and LaCl_3-KCl-NaCl melts has been investigated by means of a transparent cell,cyclic voltammetry and EHMO of quantum chemistry.It is shown that the La dissolved in KCl-NaCl melt exists in...Dissolutionof La in KCl-NaCl and LaCl_3-KCl-NaCl melts has been investigated by means of a transparent cell,cyclic voltammetry and EHMO of quantum chemistry.It is shown that the La dissolved in KCl-NaCl melt exists in a metallic state,the La dissolved in LaCl_3-KCl-NaCl melt can be ionized into La^(2+) as a result of reaction with La^(3+), furthermore,the La^(2+) reacts with La^(3+) forming atom cluster La_m^(n+) which is a stable state in the melt.展开更多
1.IntroductionDunn and Farrington[1]found that theNa ion in Naβ″-alumina single crystal canbe exchanged completely or partially withGd;,Nd;,Eu;,Yb;,Sm;,Tb;,Dy;,Bi;and Pr;ions,but no reports havebeen published about ...1.IntroductionDunn and Farrington[1]found that theNa ion in Naβ″-alumina single crystal canbe exchanged completely or partially withGd;,Nd;,Eu;,Yb;,Sm;,Tb;,Dy;,Bi;and Pr;ions,but no reports havebeen published about the ion exchange reac-tion between La3+ and Naβ″-alumina.If anion exchanged polycrystalline β″-alumina isavailable and its ionic conductivity is highenough to be applied as a solid electrolyte inthe galvanic cell,it can be used in various展开更多
Cucumber seedlings were sprayed with different concentrations of LaCl_3 for 3 d continuously. After 7 d of this treatment, the plants were treated with 1200 mg·L^(-1) 2,4-dichlorophennoxy(2,4-D) for 24 h. The lea...Cucumber seedlings were sprayed with different concentrations of LaCl_3 for 3 d continuously. After 7 d of this treatment, the plants were treated with 1200 mg·L^(-1) 2,4-dichlorophennoxy(2,4-D) for 24 h. The leaves were harvested and rinsed with 5 mmol·L^(-1) EDTA. The concentrations of photosynthetic pigments, soluble protein and metabolites related to oxidative stress and the activities of antioxidant enzymes in leaves were assayed. The results show that the treatment with appropriate concentration of LaCl_3 has resistant effect on oxidative stress induced by 2, 4-D. Proper concentration of LaCl_3 promotes the activity of antioxidant system in plants and alleviates the damage caused by 2, 4-D.展开更多
Two surfaces correponding to LaCl_3 and α-solid solution(MgCl_2.LiCl) respectively: and one secondary crystallization curve with a minimum M at 63.8 wt-％ LaCl_3,2.0 wt-％ MgCl_2,34.2 wt-％ LiCl and 492℃ were fonud ...Two surfaces correponding to LaCl_3 and α-solid solution(MgCl_2.LiCl) respectively: and one secondary crystallization curve with a minimum M at 63.8 wt-％ LaCl_3,2.0 wt-％ MgCl_2,34.2 wt-％ LiCl and 492℃ were fonud by means of DTA.In combination with liquidus determination.an approach was also made to the alteration in LnCl_3-MgCl_2-LiCl svstem,where Lu denotes La.Ce.Pr or Nd.展开更多
The effect and the action mechanism of lanthanum on GF_(43) plantlet in vitro were studied. The results of experiments show that root growth rate and dry weight of GF_(43) by LaCl_3 treatments increase. The activities...The effect and the action mechanism of lanthanum on GF_(43) plantlet in vitro were studied. The results of experiments show that root growth rate and dry weight of GF_(43) by LaCl_3 treatments increase. The activities of antioxidant enzymes in root system such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) apparently enhance. Moreover ·O^-_2 and malond ialdehyde (MDA) contents and cell membrane permeability of GF_(43) are decreased by LaCl_3. The relatively stable membrane structure of cell could also be maintained and the root ageing of GF_(43) plantlet in vitro delays.展开更多
本文利用盆栽实验研究了 L a Cl3对烟草幼苗的生物效应。在烟苗长到 3～ 4片叶时 ,用不同浓度的 L a-Cl3溶液喷施 ,实验结果表明 :2 5～ 75 m g/ L L a Cl3的溶液均能促进烟苗的生长 ,增加株高、单株干重和根干重 ,提高根 /冠比 ,增加...本文利用盆栽实验研究了 L a Cl3对烟草幼苗的生物效应。在烟苗长到 3～ 4片叶时 ,用不同浓度的 L a-Cl3溶液喷施 ,实验结果表明 :2 5～ 75 m g/ L L a Cl3的溶液均能促进烟苗的生长 ,增加株高、单株干重和根干重 ,提高根 /冠比 ,增加叶片的叶绿素含量和提高叶片的净光合速率。处理的烟苗抗寒性也有所增强。烟苗在 0～ 2℃的低温下 ,原生质结构破坏的程度减轻 ,外渗物质的量减少 ,处理的比对照的电导率减少 0 .0 1～ 0 .18× 10 - 4 s/ m。喷 L a Cl3溶液的烟苗叶片总含水量有所下降 ,但束缚水含量提高 。展开更多
Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,thre...Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,three new angucyclines,nocardiopsistins A-C,were isolated from Nocardiopsis sp.strain HB-J378.Notably,the supplementation of the rare earth salt Lanthanum chloride(LaCl3)during fermentation of HB-J378 significantly increased the yield of these angucyclines.The structures of nocardiopsistins A-C were identified by 1D and 2D NMR and HR-MS data.Nocardiopsistins A-C have activity against MRSA(methicillin-resistant Staphylococcus aureus)with MICs of 3.12–12.5μg/mL;the potency of nocardiopsistin B is similar to that of the positive control,chloramphenicol.Bioinformatic analysis of the draft genome of HB-J378 identified a set of three core genes in a biosynthetic gene cluster that encode a typical aromatic or type II polyketide synthase(PKS)system,including ketoacyl:ACP synthaseα-subunit(KSα),β-subunit(KSβ)and acyl carrier protein(ACP).The production of nocardiopsistins A-C was abolished when the three genes were knocked out,indicating their indispensable role in the production of nocardiopsistins.展开更多
文摘以质膜 Ca2 +通道阻断剂 L a Cl3和钙调素 (Ca M)拮抗剂氯丙嗪 (CPZ)对水稻幼苗预处理以阻碍 Ca2 +· Ca M信使传导后 ,研究了盐胁迫下 ,稻苗保护酶活性的变化。结果表明 :0 .15 mol/ L Na Cl胁迫下 ,L a Cl3和 CPZ预处理显著加剧稻苗过氧化氢酶 (CAT)活性和抗坏血酸过氧化物酶 (APX)活性下降 ;对谷胱甘肽还原酶 (GR)活性则无明显影响 ;而超氧化物岐化酶 (SOD)和过氧化物酶 (POD)活性前期无明显变化 ,仅在胁迫后期明显下降。盐胁迫下 ,L a Cl3和 CPZ预处理加剧 SOD、 CAT和 APX活性下降与加剧稻苗 MDA含量积累呈显著或极显著正相关。这暗示 Ca2 + · Ca
文摘Dissolutionof La in KCl-NaCl and LaCl_3-KCl-NaCl melts has been investigated by means of a transparent cell,cyclic voltammetry and EHMO of quantum chemistry.It is shown that the La dissolved in KCl-NaCl melt exists in a metallic state,the La dissolved in LaCl_3-KCl-NaCl melt can be ionized into La^(2+) as a result of reaction with La^(3+), furthermore,the La^(2+) reacts with La^(3+) forming atom cluster La_m^(n+) which is a stable state in the melt.
文摘1.IntroductionDunn and Farrington[1]found that theNa ion in Naβ″-alumina single crystal canbe exchanged completely or partially withGd;,Nd;,Eu;,Yb;,Sm;,Tb;,Dy;,Bi;and Pr;ions,but no reports havebeen published about the ion exchange reac-tion between La3+ and Naβ″-alumina.If anion exchanged polycrystalline β″-alumina isavailable and its ionic conductivity is highenough to be applied as a solid electrolyte inthe galvanic cell,it can be used in various
文摘Cucumber seedlings were sprayed with different concentrations of LaCl_3 for 3 d continuously. After 7 d of this treatment, the plants were treated with 1200 mg·L^(-1) 2,4-dichlorophennoxy(2,4-D) for 24 h. The leaves were harvested and rinsed with 5 mmol·L^(-1) EDTA. The concentrations of photosynthetic pigments, soluble protein and metabolites related to oxidative stress and the activities of antioxidant enzymes in leaves were assayed. The results show that the treatment with appropriate concentration of LaCl_3 has resistant effect on oxidative stress induced by 2, 4-D. Proper concentration of LaCl_3 promotes the activity of antioxidant system in plants and alleviates the damage caused by 2, 4-D.
文摘Two surfaces correponding to LaCl_3 and α-solid solution(MgCl_2.LiCl) respectively: and one secondary crystallization curve with a minimum M at 63.8 wt-％ LaCl_3,2.0 wt-％ MgCl_2,34.2 wt-％ LiCl and 492℃ were fonud by means of DTA.In combination with liquidus determination.an approach was also made to the alteration in LnCl_3-MgCl_2-LiCl svstem,where Lu denotes La.Ce.Pr or Nd.
文摘The effect and the action mechanism of lanthanum on GF_(43) plantlet in vitro were studied. The results of experiments show that root growth rate and dry weight of GF_(43) by LaCl_3 treatments increase. The activities of antioxidant enzymes in root system such as superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD) apparently enhance. Moreover ·O^-_2 and malond ialdehyde (MDA) contents and cell membrane permeability of GF_(43) are decreased by LaCl_3. The relatively stable membrane structure of cell could also be maintained and the root ageing of GF_(43) plantlet in vitro delays.
文摘本文利用盆栽实验研究了 L a Cl3对烟草幼苗的生物效应。在烟苗长到 3～ 4片叶时 ,用不同浓度的 L a-Cl3溶液喷施 ,实验结果表明 :2 5～ 75 m g/ L L a Cl3的溶液均能促进烟苗的生长 ,增加株高、单株干重和根干重 ,提高根 /冠比 ,增加叶片的叶绿素含量和提高叶片的净光合速率。处理的烟苗抗寒性也有所增强。烟苗在 0～ 2℃的低温下 ,原生质结构破坏的程度减轻 ,外渗物质的量减少 ,处理的比对照的电导率减少 0 .0 1～ 0 .18× 10 - 4 s/ m。喷 L a Cl3溶液的烟苗叶片总含水量有所下降 ,但束缚水含量提高 。
基金This work was supported in part by the NIH grant CA209189.
文摘Marine natural products have become an increasingly important source of new drug leads during recent years.In an attempt to identify novel anti-microbial natural products by bioprospecting deep-sea Actinobacteria,three new angucyclines,nocardiopsistins A-C,were isolated from Nocardiopsis sp.strain HB-J378.Notably,the supplementation of the rare earth salt Lanthanum chloride(LaCl3)during fermentation of HB-J378 significantly increased the yield of these angucyclines.The structures of nocardiopsistins A-C were identified by 1D and 2D NMR and HR-MS data.Nocardiopsistins A-C have activity against MRSA(methicillin-resistant Staphylococcus aureus)with MICs of 3.12–12.5μg/mL;the potency of nocardiopsistin B is similar to that of the positive control,chloramphenicol.Bioinformatic analysis of the draft genome of HB-J378 identified a set of three core genes in a biosynthetic gene cluster that encode a typical aromatic or type II polyketide synthase(PKS)system,including ketoacyl:ACP synthaseα-subunit(KSα),β-subunit(KSβ)and acyl carrier protein(ACP).The production of nocardiopsistins A-C was abolished when the three genes were knocked out,indicating their indispensable role in the production of nocardiopsistins.
