Aim Isolation and structural elucidation of the constituents from the dried flower buds of Magnolia biondii Pamp. Methods Column chromatography and TLC were used to isolate chemical constituents. Spectroscopic methods...Aim Isolation and structural elucidation of the constituents from the dried flower buds of Magnolia biondii Pamp. Methods Column chromatography and TLC were used to isolate chemical constituents. Spectroscopic methods were employed for structural elucidation. Results One benzo furanoid neolignan （licarin B） and two bisepoxy lignans （magnolin, fargesin） were isolated and identified. Conclusion Licarin B is the first reported benzofuranoid lignan from the family Magnoliaceae.展开更多
[Objective] The aim was to explore the relationship of pollen types and blooming plants,pollen fertility and meteorological factors during the falling process of pollen in the atmosphere.[Method] The falling record of...[Objective] The aim was to explore the relationship of pollen types and blooming plants,pollen fertility and meteorological factors during the falling process of pollen in the atmosphere.[Method] The falling record of pollen in Lanzhou University in spring in 2009 was obtained by 10 m platform natural falling method.The pollen falling number,duration,relationship among falling types and surrounding plants,as well as weather were discussed.[Result] Main pollen types included Populus L.,Salix,Paulownia and Platanaceae.Its pollen falling number,duration was consistent with the flowering period of corresponding plants in the garden;the classification and richness of falling of pollen was influenced by wind.The larger the wind was,the richer the variety become.There was basically no pollen from outside.The authors failed to observe the distinct changes of palynological assemblage in sandy storm weather.[Conclusion] The study could lay basis for the study of the modern progress of natural plants pollen.展开更多
AIM: To determine seroprevalence of Helicobacter pylori (Hpylori)in the Dunedin Multidisciplinary Health and Development Study (DMHDS) at age 26 in order to investigate seroconversion and seroreversion from age 11 to ...AIM: To determine seroprevalence of Helicobacter pylori (Hpylori)in the Dunedin Multidisciplinary Health and Development Study (DMHDS) at age 26 in order to investigate seroconversion and seroreversion from age 11 to 26 and the association of seropositivity with risk factors for H pylori infection. METHODS: Participants in the DMHDS at age 26 and retrospectively at age 21 were tested for H pylori antibodies using two commercially available ELISA kits.Gender, socioeconomic status (SES), smoking,educational attainment and employment at age 26 were tested for association with H pylori seropositivity. RESULTS: At ages 21 and 26,seroprevalence of H pylori using one or other kit was 4.2% (n=795) and 6.3% (n=871) respectively, Seroreversion rate was lower than seroconversion rate (0.11% vs 0.53% per person-year) in contrast to the period from age 11 to 21 when seroreversion rate exceeded seroconversion rate (0.35% vs 0.11% per person-year). Serology in those tested at ages 11, 21, and 26 remained unchanged in 93.6% of the sample. Seroprevalence at age 26 was lower among those with a secondary school qualification (P=0.042) but was not associated with gender, SES, smoking or employment status. CONCLUSION: H pylori seroprevalence in a New Zealand birth cohort remains low between ages 11 and 26. H pylori infection remains stable from childhood to adulthood although seroreversion seems to be more common in the adolescent years than in young adults.展开更多
文摘Aim Isolation and structural elucidation of the constituents from the dried flower buds of Magnolia biondii Pamp. Methods Column chromatography and TLC were used to isolate chemical constituents. Spectroscopic methods were employed for structural elucidation. Results One benzo furanoid neolignan （licarin B） and two bisepoxy lignans （magnolin, fargesin） were isolated and identified. Conclusion Licarin B is the first reported benzofuranoid lignan from the family Magnoliaceae.
基金Supported by Foundation for Excellent Youth Scholars of CAREERI,CAS(51Y184991)~~
文摘[Objective] The aim was to explore the relationship of pollen types and blooming plants,pollen fertility and meteorological factors during the falling process of pollen in the atmosphere.[Method] The falling record of pollen in Lanzhou University in spring in 2009 was obtained by 10 m platform natural falling method.The pollen falling number,duration,relationship among falling types and surrounding plants,as well as weather were discussed.[Result] Main pollen types included Populus L.,Salix,Paulownia and Platanaceae.Its pollen falling number,duration was consistent with the flowering period of corresponding plants in the garden;the classification and richness of falling of pollen was influenced by wind.The larger the wind was,the richer the variety become.There was basically no pollen from outside.The authors failed to observe the distinct changes of palynological assemblage in sandy storm weather.[Conclusion] The study could lay basis for the study of the modern progress of natural plants pollen.
文摘AIM: To determine seroprevalence of Helicobacter pylori (Hpylori)in the Dunedin Multidisciplinary Health and Development Study (DMHDS) at age 26 in order to investigate seroconversion and seroreversion from age 11 to 26 and the association of seropositivity with risk factors for H pylori infection. METHODS: Participants in the DMHDS at age 26 and retrospectively at age 21 were tested for H pylori antibodies using two commercially available ELISA kits.Gender, socioeconomic status (SES), smoking,educational attainment and employment at age 26 were tested for association with H pylori seropositivity. RESULTS: At ages 21 and 26,seroprevalence of H pylori using one or other kit was 4.2% (n=795) and 6.3% (n=871) respectively, Seroreversion rate was lower than seroconversion rate (0.11% vs 0.53% per person-year) in contrast to the period from age 11 to 21 when seroreversion rate exceeded seroconversion rate (0.35% vs 0.11% per person-year). Serology in those tested at ages 11, 21, and 26 remained unchanged in 93.6% of the sample. Seroprevalence at age 26 was lower among those with a secondary school qualification (P=0.042) but was not associated with gender, SES, smoking or employment status. CONCLUSION: H pylori seroprevalence in a New Zealand birth cohort remains low between ages 11 and 26. H pylori infection remains stable from childhood to adulthood although seroreversion seems to be more common in the adolescent years than in young adults.
