The marginal areas of the Tibetan Plateau have great vertical altitude gradient and abundant vegetation, they are therefore the ideal places for investigating the relationships among carbon isotope composition(δ^(13)...The marginal areas of the Tibetan Plateau have great vertical altitude gradient and abundant vegetation, they are therefore the ideal places for investigating the relationships among carbon isotope composition(δ^(13)C) of modern soils, vegetation and environmental factors, which would be very useful for the reconstructions of both paleovegetation and paleoclimate. In this paper, modern soil samples collected in different vegetation vertical zones along 4km elevation gradient in the eastern margin of the Tibetan Plateau were analyzed for their carbon isotope composition. The results show that the modern soils in different vegetation vertical zones show apparent difference of δ^(13)C values, which get heavier in the sequence of mixed evergreen and deciduous broad-leaved forest(-27.28‰ on average), evergreen broad-leaved forest(-27.25‰), subalpine shrub-meadow(-25.81‰), subalpine coniferous forest(-25.81‰), alpine bush-meadow(-25.16‰), and drought-enduring shrub(-24.07‰). 1800 m and 3500 m are two critical points for the δ^(13)C values with respect to altitude. Specifically, the δ^(13)C values decrease with increasing altitude below both points while increasing with increasing altitude above both points. Further analyses indicate that the declining δ^(13)C values are mainly controlled by the decreasing proportion of C4 plants with elevation and the increasing δ^(13)C values are attributed to the plant physic-morphological adaptation to the alpine environment. In the absence of drought stress, temperature is the main controlling factor for the carbon isotopic variations with altitude gradient.展开更多
BACKGROUND The incidence of hepatocellular carcinoma(HCC)is high in China,and approximately 15%-20%of HCC cases occur in the absence of cirrhosis.Compared with patients with cirrhotic HCC,those with non-cirrhotic HCC ...BACKGROUND The incidence of hepatocellular carcinoma(HCC)is high in China,and approximately 15%-20%of HCC cases occur in the absence of cirrhosis.Compared with patients with cirrhotic HCC,those with non-cirrhotic HCC have longer postoperative tumor-free survival.However,the overall survival time is not significantly increased,and the risk of postoperative recurrence remains.Strategies to improve the postoperative survival rate in these patients are currently required.CASE SUMMARY A 47-year-old man with a family history of HCC was found to have hepatitis B virus(HBV)infection 25 years ago.In 2000,he was administered lamivudine for 2 years,and entecavir(ETV 0.5 mg)was administered in 2006.In October 2016,magnetic resonance imaging revealed a tumor in the liver(5.3 cm×5 cm×5 cm);no intraoperative hepatic and portal vein and bile duct tumor thrombi were found;and postoperative pathological examination confirmed a grade II HCC with no nodular cirrhosis(G1S3).ETV was continued,and no significant changes were observed on imaging.After receiving pegylated interferon alfa-2b(PEG IFNα-2b)(180μg)+ETV in February 2019,the HBsAg titer decreased significantly within 12 wk.After receiving hepatitis B vaccine(60μg)in 12 wk,HBsAg serological conversion was realized at 48 wk.During the treatment,no obvious adverse reactions were observed,except for early alanine aminotransferase flares.The reexamination results of liver pathology were G2S1,and reversal of liver fibrosis was achieved.CONCLUSION The therapeutic regimen of ETV+PEG IFNα-2b+hepatitis B vaccine for patients with HBV-associated non-cirrhotic HCC following hepatectomy can achieve an HBV clinical cure and prolong the recurrence-free survival.展开更多
基金supported by the National Natural Science Foundation of China (grant nos. 41888101, 41907377 and 41772383)the Special Fund for Basic Scientific Research of China University of Geosciences (grant no. 53200859557)。
文摘The marginal areas of the Tibetan Plateau have great vertical altitude gradient and abundant vegetation, they are therefore the ideal places for investigating the relationships among carbon isotope composition(δ^(13)C) of modern soils, vegetation and environmental factors, which would be very useful for the reconstructions of both paleovegetation and paleoclimate. In this paper, modern soil samples collected in different vegetation vertical zones along 4km elevation gradient in the eastern margin of the Tibetan Plateau were analyzed for their carbon isotope composition. The results show that the modern soils in different vegetation vertical zones show apparent difference of δ^(13)C values, which get heavier in the sequence of mixed evergreen and deciduous broad-leaved forest(-27.28‰ on average), evergreen broad-leaved forest(-27.25‰), subalpine shrub-meadow(-25.81‰), subalpine coniferous forest(-25.81‰), alpine bush-meadow(-25.16‰), and drought-enduring shrub(-24.07‰). 1800 m and 3500 m are two critical points for the δ^(13)C values with respect to altitude. Specifically, the δ^(13)C values decrease with increasing altitude below both points while increasing with increasing altitude above both points. Further analyses indicate that the declining δ^(13)C values are mainly controlled by the decreasing proportion of C4 plants with elevation and the increasing δ^(13)C values are attributed to the plant physic-morphological adaptation to the alpine environment. In the absence of drought stress, temperature is the main controlling factor for the carbon isotopic variations with altitude gradient.
基金Natural Science Foundation of Fujian Province,No.2019J01593High-Level Talent Innovation Project of Quanzhou,No.2018C067R+2 种基金Science and Technology Innovation Joint Project of Fujian Province,No.2019Y9048Youth Research Project of Fujian Provincial Health Commission,No.2018-1-94 and No.2018-1-95Science and Technology Project of Quanzhou,No.2018Z074 and No.2018Z069.
文摘BACKGROUND The incidence of hepatocellular carcinoma(HCC)is high in China,and approximately 15%-20%of HCC cases occur in the absence of cirrhosis.Compared with patients with cirrhotic HCC,those with non-cirrhotic HCC have longer postoperative tumor-free survival.However,the overall survival time is not significantly increased,and the risk of postoperative recurrence remains.Strategies to improve the postoperative survival rate in these patients are currently required.CASE SUMMARY A 47-year-old man with a family history of HCC was found to have hepatitis B virus(HBV)infection 25 years ago.In 2000,he was administered lamivudine for 2 years,and entecavir(ETV 0.5 mg)was administered in 2006.In October 2016,magnetic resonance imaging revealed a tumor in the liver(5.3 cm×5 cm×5 cm);no intraoperative hepatic and portal vein and bile duct tumor thrombi were found;and postoperative pathological examination confirmed a grade II HCC with no nodular cirrhosis(G1S3).ETV was continued,and no significant changes were observed on imaging.After receiving pegylated interferon alfa-2b(PEG IFNα-2b)(180μg)+ETV in February 2019,the HBsAg titer decreased significantly within 12 wk.After receiving hepatitis B vaccine(60μg)in 12 wk,HBsAg serological conversion was realized at 48 wk.During the treatment,no obvious adverse reactions were observed,except for early alanine aminotransferase flares.The reexamination results of liver pathology were G2S1,and reversal of liver fibrosis was achieved.CONCLUSION The therapeutic regimen of ETV+PEG IFNα-2b+hepatitis B vaccine for patients with HBV-associated non-cirrhotic HCC following hepatectomy can achieve an HBV clinical cure and prolong the recurrence-free survival.
