Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB p...Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.展开更多
Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitabl...Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017.Based on the understanding of the first production test,the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment,numerical and experimental simulation,and onshore testing of the reservoirs.After that,it conducted the second offshore NGH production test in 1225 m deep Shenhu Area,South China Sea(also referred to as the second production test)from October 2019 to April 2020.During the second production test,a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met,including wellhead stability,directional drilling of a horizontal well,reservoir stimulation and sand control,and accurate depressurization.As a result,30 days of continuous gas production was achieved,with a cumulative gas production of 86.14×104 m3.Thus,the average daily gas production is 2.87×10^4 m^3,which is 5.57 times as much as that obtained in the first production test.Therefore,both the cumulative gas production and the daily gas production were highly improved compared to the first production test.As indicated by the monitoring results of the second production test,there was no anomaly in methane content in the seafloor,seawater,and atmosphere throughout the whole production test.This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs.The industrialization of hydrates consists of five stages in general,namely theoretical research and simulation experiments,exploratory production test,experimental production test,productive production test,and commercial production.The second production test serves as an important step from the exploratory production test to exper展开更多
The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effecti...The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.展开更多
A pot experiment was conducted in artificially Cd-contaminated （5 mg Cd kg 1） soils to investigate the feasibility of using lime （3 g kg-1） or phosphate （80 mg P kg-1） to mitigate uptake of Cd by vegetables. Fiv...A pot experiment was conducted in artificially Cd-contaminated （5 mg Cd kg 1） soils to investigate the feasibility of using lime （3 g kg-1） or phosphate （80 mg P kg-1） to mitigate uptake of Cd by vegetables. Five common vegetables in South China, including lettuce （Lactuca sativa L. var. ramosa Hort.）, Chinese cabbage [Brassica rapa L. subsp. Chinensis （L.） var. parachinensis （L. H. Bailey） Hanect], Chinese broccoli （Brassica oleracea L. vat. albiflora Kuntze）, white amaranth （Amaranthus tricolor L.） and purslane （Amaranthus viridis L.）, were grown in the soils and harvested after 60 d. The results showed that liming significantly reduced Cd uptake by most vegetables by 40%-50% （or a maximum of 70%）, mainly due to immobilization of soil Cd. Increased availability of Ca in the soil might also contribute to the Cd uptake reduction as a result of absorption competition between Ca and Cd. Liming caused biomass reduction in white amaranth and purslane, but did not influence growth of the other vegetables. Phosphate decreased Cd uptake by vegetables by 12% 23%. Compared with lime, phosphate decreased, to a smaller extent, the bioavailability of Cd in most cases. Phosphate markedly promoted growth of vegetables. Changes in soil chemistry by adding lime or phosphate did not markedly influence nutrient uptake of vegetables except that lime increased Ca content and phosphate increased P content in shoots of the vegetables. The results suggested that a proper application of lime could be effective in reducing Cd uptake of vegetables, and phosphate could promote growth of the vegetables as well as alleviate the toxicity of Cd.展开更多
Advanced intrahepatic cholangiocarcinoma(ICC)has a dismal prognosis.Here,we report the efficacy and safety of combining toripalimab,lenvatinib,and gemcitabine plus oxaliplatin(GEMOX)as first-line therapy for advanced ...Advanced intrahepatic cholangiocarcinoma(ICC)has a dismal prognosis.Here,we report the efficacy and safety of combining toripalimab,lenvatinib,and gemcitabine plus oxaliplatin(GEMOX)as first-line therapy for advanced ICC.Thirty patients with pathologically confirmed advanced ICC received intravenous gemcitabine(1 g/m2)on Days 1 and 8 and oxaliplatin(85 mg/m2)Q3W for six cycles along with intravenous toripalimab(240 mg)Q3W and oral lenvatinib(8 mg)once daily for one year.The expression of programmed death-ligand 1(PD-L1)and genetic status was investigated in paraffin-embedded tissues using immunohistochemistry and whole-exome sequencing(WES)analysis.The primary endpoint was the objective response rate(ORR).Secondary outcomes included safety,overall survival(OS),progression-free survival(PFS),disease control rate(DCR)and duration of response(DoR).As of July 1,2022,the median follow-up time was 23.5 months,and the ORR was 80%.Twenty-three patients achieved partial response,and one achieved complete response.Patients(21/30)with DNA damage response(DDR)-related gene mutations showed a higher ORR,while patients(14/30)with tumor area positivity≥1(PD-L1 staining)showed a trend of high ORR,but without significant difference.The median OS,PFS,and DoR were 22.5,10.2,and 11.0 months,respectively.The DCR was 93.3%.Further,56.7%of patients experienced manageable grade≥3 adverse events(AEs),commonly neutropenia(40.0%)and leukocytopenia(23.3%).In conclusion,toripalimab plus lenvatinib and GEMOX are promising first-line regimens for the treatment of advanced ICC.A phase-III,multicenter,double-blinded,randomized study to validate our findings was approved by the National Medical Products Administration(NMPA,No.2021LP01825).展开更多
The presence of pharmaceuticals and personal care products(PPCPs)in the aquatic environment may pose potential threat to the ecosystem and human health,hence PPCPs have aroused much concern over the world.The contamin...The presence of pharmaceuticals and personal care products(PPCPs)in the aquatic environment may pose potential threat to the ecosystem and human health,hence PPCPs have aroused much concern over the world.The contamination of PPCPs in the groundwater,the main source of drinking water supply in many countries and regions,has been extensively studied in the last decade.This paper reviews the occurrence of frequently detected PPCPs,including antibiotics,anti-inflammatories,lipid-regulators,carbamazepine,caffeine,and N,N-diethyl-m-toluamide in groundwater,with special concern to the progress made over the past three years.Possible emission sources for PPCPs in groundwater,such as wastewater and contaminated surface water,landfills,septic systems,livestock breeding and sewer leakage,are summarized.Besides,adsorption,migration and degradation,the dominant mechanisms in the subsurface transport and fate of PPCPs,are discussed,and the insights into the future study of PPCPs in the groundwater are provided.展开更多
1.Introduction The China Seismo-Electromagnetic Satellite (CSES), which is also called ZhangHeng-1 (ZH-1), is the first Chinese space-borne platform dedicated to geophysical field measurement andearthquake monitoring ...1.Introduction The China Seismo-Electromagnetic Satellite (CSES), which is also called ZhangHeng-1 (ZH-1), is the first Chinese space-borne platform dedicated to geophysical field measurement andearthquake monitoring by detecting variations in the electromagnetic environment of space. The CSES was launched successfully at15:51 on February 2, 2018, at China’s Jiuquan Satellite Launching Center.展开更多
In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flour...In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flourishing area, Chinese chemists have devoted great efforts to different aspects of synthetic chemistry. This review will summarize their representative work according to the following categories: C–H functionalization, synthesis of aromatic aza-heterocycles, asymmetric organic photochemical synthesis, transformations of small molecules and biomolecule-compatible reactions.展开更多
目的探讨美罗培南治疗新生儿耐碳青霉烯类肺炎克雷伯菌(CRKP)败血症的疗效及其影响因素,为临床合理使用抗生素提供参考依据。方法采用回顾性研究方法,收集2014年6月至2018年6月在上海交通大学附属儿童医院新生儿科住院的27例CRKP败血症...目的探讨美罗培南治疗新生儿耐碳青霉烯类肺炎克雷伯菌(CRKP)败血症的疗效及其影响因素,为临床合理使用抗生素提供参考依据。方法采用回顾性研究方法,收集2014年6月至2018年6月在上海交通大学附属儿童医院新生儿科住院的27例CRKP败血症患儿的临床资料,分析美罗培南在27例患儿中的治疗效果。根据治疗效果将患儿分为美罗培南单药治疗有效组和美罗培南单药治疗无效需联合治疗组,比较两组患儿围产因素、感染CRKP前接受碳青酶烯类抗生素暴露等临床特点的差异。结果美罗培南单药治疗新生儿CRKP败血症有效率为48.1%(13/27),采用联合治疗后总体有效率为74.1%(20/27)。美罗培南单药治疗无效需联合治疗组患儿存在外科手术后开放性伤口(7/14 vs 1/13)、感染性休克(7/14 vs 1/13)、无菌体腔液(脑脊液及腹水)培养阳性(6/14 vs 0/13)、感染时需有创机械通气(10/14 vs 1/13)的患儿比例高于单药治疗有效组(P均<0.05),纸片扩散法药物敏感性试验中美罗培南抑菌圈直径小于单药治疗有效组[(9.14±3.37) mm vs (12.85±5.27) mm,P<0.05]。结论美罗培南单药治疗新生儿CRKP败血症具有一定疗效。当CRKP败血症患儿存在外科手术后开放性伤口、感染性休克、无菌体腔液培养阳性、感染时需有创机械通气及药物敏感性试验中美罗培南抑菌圈直径偏小时需联合治疗,以提高治疗有效率。展开更多
This paper aims to estimate the soil organic carbon （SOC） storage in Northeast of China, identify its balance situation and changing trends under current cropping systems, and finally put forward some strategies to ...This paper aims to estimate the soil organic carbon （SOC） storage in Northeast of China, identify its balance situation and changing trends under current cropping systems, and finally put forward some strategies to keep the SOC in balance. A biogeochemical model （DNDC） for agro-ecosystem was employed to predict SOC dynamics in agricultural ecosystems at regional scale. Data on climate, soil properties, cropping systems, acreage, and management practices at county scale were collected from various sources and integrated into a GIS database to support the model runs at the regional scale. The model predicted results revealed that （1） Total SOC storage in agricultural lands in Heilongjiang, Jilin and Liaoning provinces in Northeast of China is about 1 243.48 × 10^6 t （0-30cm soil layer）, respectively occupying 58.4, 25.5 and 16.1%; （2） Under the current cultivation systems, SOC is in a situation of net loss with carbon losing at a high rate of 31.22 × 10^6 t a^-1 （respectively 59.3, 25.9 and 14.8% in Heilongjiang, Jilin and Liaoning provinces） and 2.05 t ha^-1 a^-1, the situation is more serious in Heilongjiang and Jilin provinces; and （3） Protective cultivations, such as manuring, returning more residue of crop to the field, adopting no-till, are very useful for the accumulation of SOC in these regions.展开更多
文摘Aim: To study the integration of hepatitis B virus (HBV) DNA into sperm chromosomes in hepatitis B patients and the features of its integration. Methods: Sperm chromosomes of 14 subjects (5 healthy controls and 9 HB patients, including 1 acute hepatitis B, 2 chronic active hepatitis B, 4 chronic persistent hepatitis B, 2 HBsAg chronic carriers with no clinical symptoms) were prepared using interspecific in vitro fertilization between zona-free hamster oocytes and human spermatozoa. Fluorescence in situ hybridization (FISH) to sperm chromosome spreads was carried out with biotin-labeled full length HBV DNA probe to detect the specific HBV DNA sequences in the sperm chromosomes. Results: Specific fluorescent signal spots for HBV DNA were seen in sperm chromosomes of one patient with chronic persistent hepatitis B. In 9(9/42) sperm chromosome complements containing fluorescent signal spots, one presented 5 obvious FISH spots and the others 2 to 4 signals. The fluorescence intensity showed significant difference among the signal spots. The distribution of signal sites among chromosomes seems to be random. Conclusion: HBV could integrate into human sperm chromosomes. Results suggest that the possibility of vertical transmission of HBV via the germ line to the next generation is present.
基金This study is supported by the offshore NGH production test projects under the Marine Geological Survey Program initiated by the China Geological Survey(DD20190226,DD20190218)the Major Program of National Natural Science Foundation of China(41730528,51991365)。
文摘Clayey silt reservoirs bearing natural gas hydrates(NGH)are considered to be the hydrate-bearing reservoirs that boast the highest reserves but tend to be the most difficult to exploit.They are proved to be exploitable by the first NGH production test conducted in the South China Sea in 2017.Based on the understanding of the first production test,the China Geological Survey determined the optimal target NGH reservoirs for production test and conducted a detailed assessment,numerical and experimental simulation,and onshore testing of the reservoirs.After that,it conducted the second offshore NGH production test in 1225 m deep Shenhu Area,South China Sea(also referred to as the second production test)from October 2019 to April 2020.During the second production test,a series of technical challenges of drilling horizontal wells in shallow soft strata in deep sea were met,including wellhead stability,directional drilling of a horizontal well,reservoir stimulation and sand control,and accurate depressurization.As a result,30 days of continuous gas production was achieved,with a cumulative gas production of 86.14×104 m3.Thus,the average daily gas production is 2.87×10^4 m^3,which is 5.57 times as much as that obtained in the first production test.Therefore,both the cumulative gas production and the daily gas production were highly improved compared to the first production test.As indicated by the monitoring results of the second production test,there was no anomaly in methane content in the seafloor,seawater,and atmosphere throughout the whole production test.This successful production test further indicates that safe and effective NGH exploitation is feasible in clayey silt NGH reservoirs.The industrialization of hydrates consists of five stages in general,namely theoretical research and simulation experiments,exploratory production test,experimental production test,productive production test,and commercial production.The second production test serves as an important step from the exploratory production test to exper
文摘The Large Sky Area Multi-Object Fiber Spectroscopic Telescope (LAMOST, also called the Guo Shou Jing Telescope) is a special reflecting Schmidt telescope. LAMOST’s special design allows both a large aperture (effective aperture of 3.6 m–4.9 m) and a wide field of view (FOV) (5°). It has an innovative active reflecting Schmidt configuration which continuously changes the mirror’s surface that adjusts during the observation process and combines thin deformable mirror active optics with segmented active optics. Its primary mirror (6.67m×6.05 m) and active Schmidt mirror (5.74m×4.40 m) are both segmented, and composed of 37 and 24 hexagonal sub-mirrors respectively. By using a parallel controllable fiber positioning technique, the focal surface of 1.75 m in diameter can accommodate 4000 optical fibers. Also, LAMOST has 16 spectrographs with 32 CCD cameras. LAMOST will be the telescope with the highest rate of spectral acquisition. As a national large scientific project, the LAMOST project was formally proposed in 1996, and approved by the Chinese government in 1997. The construction started in 2001, was completed in 2008 and passed the official acceptance in June 2009. The LAMOST pilot survey was started in October 2011 and the spectroscopic survey will launch in September 2012. Up to now, LAMOST has released more than 480 000 spectra of objects. LAMOST will make an important contribution to the study of the large-scale structure of the Universe, structure and evolution of the Galaxy, and cross-identification of multiwaveband properties in celestial objects.
基金Supported by the National Natural Science Foundation of China (Nos. 30870442 and 30630015)the National Basic Research Program(973 Program) of China (No. 2009CB421101)+2 种基金the National High Technology Research and Development Program (863 Program) of China (No. 2007AA061001)the Guangdong Provincial Natural Science Foundation of China (No. 9151001002000001)the key lab(No. 2009DP173224) of Vegetation Restoration and Management of Degraded Ecosystems,Chinese Academy of Sciences for providing the experimental site
文摘A pot experiment was conducted in artificially Cd-contaminated （5 mg Cd kg 1） soils to investigate the feasibility of using lime （3 g kg-1） or phosphate （80 mg P kg-1） to mitigate uptake of Cd by vegetables. Five common vegetables in South China, including lettuce （Lactuca sativa L. var. ramosa Hort.）, Chinese cabbage [Brassica rapa L. subsp. Chinensis （L.） var. parachinensis （L. H. Bailey） Hanect], Chinese broccoli （Brassica oleracea L. vat. albiflora Kuntze）, white amaranth （Amaranthus tricolor L.） and purslane （Amaranthus viridis L.）, were grown in the soils and harvested after 60 d. The results showed that liming significantly reduced Cd uptake by most vegetables by 40%-50% （or a maximum of 70%）, mainly due to immobilization of soil Cd. Increased availability of Ca in the soil might also contribute to the Cd uptake reduction as a result of absorption competition between Ca and Cd. Liming caused biomass reduction in white amaranth and purslane, but did not influence growth of the other vegetables. Phosphate decreased Cd uptake by vegetables by 12% 23%. Compared with lime, phosphate decreased, to a smaller extent, the bioavailability of Cd in most cases. Phosphate markedly promoted growth of vegetables. Changes in soil chemistry by adding lime or phosphate did not markedly influence nutrient uptake of vegetables except that lime increased Ca content and phosphate increased P content in shoots of the vegetables. The results suggested that a proper application of lime could be effective in reducing Cd uptake of vegetables, and phosphate could promote growth of the vegetables as well as alleviate the toxicity of Cd.
基金National Natural Science Foundation of China(81972232,81830102,82150004)Clinical Research Plan of SHDC(SHDC‑2020CR1003A,SHDC-2020CR1022B)+3 种基金National Key Research and Development Program of China(2019YFC1316000,2019YFC1315800,and 2019YFC1315802)the Key Disease Joint Research Program of Xuhui District(XHLHGG202103),the Clinical Medicine Research Pilot Project of Shanghai Medical School of Fudan University(2020,21DGF501035/00)the Shanghai Municipal Natural Science Foundation(20JC1419103,21ZR1412200)Beijing Mutual Care Public Welfare Foundation(GDXZ-08-05)Sanming Project of Medicine in Shenzhen(SZSM202003009),and Shanghai Municipal Key Clinical Specialty Construction Project(shslczdzk02401).
文摘Advanced intrahepatic cholangiocarcinoma(ICC)has a dismal prognosis.Here,we report the efficacy and safety of combining toripalimab,lenvatinib,and gemcitabine plus oxaliplatin(GEMOX)as first-line therapy for advanced ICC.Thirty patients with pathologically confirmed advanced ICC received intravenous gemcitabine(1 g/m2)on Days 1 and 8 and oxaliplatin(85 mg/m2)Q3W for six cycles along with intravenous toripalimab(240 mg)Q3W and oral lenvatinib(8 mg)once daily for one year.The expression of programmed death-ligand 1(PD-L1)and genetic status was investigated in paraffin-embedded tissues using immunohistochemistry and whole-exome sequencing(WES)analysis.The primary endpoint was the objective response rate(ORR).Secondary outcomes included safety,overall survival(OS),progression-free survival(PFS),disease control rate(DCR)and duration of response(DoR).As of July 1,2022,the median follow-up time was 23.5 months,and the ORR was 80%.Twenty-three patients achieved partial response,and one achieved complete response.Patients(21/30)with DNA damage response(DDR)-related gene mutations showed a higher ORR,while patients(14/30)with tumor area positivity≥1(PD-L1 staining)showed a trend of high ORR,but without significant difference.The median OS,PFS,and DoR were 22.5,10.2,and 11.0 months,respectively.The DCR was 93.3%.Further,56.7%of patients experienced manageable grade≥3 adverse events(AEs),commonly neutropenia(40.0%)and leukocytopenia(23.3%).In conclusion,toripalimab plus lenvatinib and GEMOX are promising first-line regimens for the treatment of advanced ICC.A phase-III,multicenter,double-blinded,randomized study to validate our findings was approved by the National Medical Products Administration(NMPA,No.2021LP01825).
基金supported by the National Natural Science Foundation(51208199,51408425)the Fundamental Research Funds for the Central Universities(22A201514057)+1 种基金Beijing Key Laboratory for Emerging Organic Contaminants Control,the Foundation of The State Key Laboratory of Pollution Control and Resource Reuse,China(PCRRG 11017)the Specialized Research Fund for the Doctoral Program of Higher Education of China(20130072120033).
文摘The presence of pharmaceuticals and personal care products(PPCPs)in the aquatic environment may pose potential threat to the ecosystem and human health,hence PPCPs have aroused much concern over the world.The contamination of PPCPs in the groundwater,the main source of drinking water supply in many countries and regions,has been extensively studied in the last decade.This paper reviews the occurrence of frequently detected PPCPs,including antibiotics,anti-inflammatories,lipid-regulators,carbamazepine,caffeine,and N,N-diethyl-m-toluamide in groundwater,with special concern to the progress made over the past three years.Possible emission sources for PPCPs in groundwater,such as wastewater and contaminated surface water,landfills,septic systems,livestock breeding and sewer leakage,are summarized.Besides,adsorption,migration and degradation,the dominant mechanisms in the subsurface transport and fate of PPCPs,are discussed,and the insights into the future study of PPCPs in the groundwater are provided.
文摘1.Introduction The China Seismo-Electromagnetic Satellite (CSES), which is also called ZhangHeng-1 (ZH-1), is the first Chinese space-borne platform dedicated to geophysical field measurement andearthquake monitoring by detecting variations in the electromagnetic environment of space. The CSES was launched successfully at15:51 on February 2, 2018, at China’s Jiuquan Satellite Launching Center.
基金supported by the National Natural Science Foundation of China(21772052,21772053,21772129,21801176,21672099,21732003)Chinese Academy of Sciences(XDB20020200)
文摘In recent years, visible light-driven organic photochemical synthesis has attracted wide research interest from academic and industrial communities due to its features of green and sustainable chemistry. In this flourishing area, Chinese chemists have devoted great efforts to different aspects of synthetic chemistry. This review will summarize their representative work according to the following categories: C–H functionalization, synthesis of aromatic aza-heterocycles, asymmetric organic photochemical synthesis, transformations of small molecules and biomolecule-compatible reactions.
文摘目的探讨美罗培南治疗新生儿耐碳青霉烯类肺炎克雷伯菌(CRKP)败血症的疗效及其影响因素,为临床合理使用抗生素提供参考依据。方法采用回顾性研究方法,收集2014年6月至2018年6月在上海交通大学附属儿童医院新生儿科住院的27例CRKP败血症患儿的临床资料,分析美罗培南在27例患儿中的治疗效果。根据治疗效果将患儿分为美罗培南单药治疗有效组和美罗培南单药治疗无效需联合治疗组,比较两组患儿围产因素、感染CRKP前接受碳青酶烯类抗生素暴露等临床特点的差异。结果美罗培南单药治疗新生儿CRKP败血症有效率为48.1%(13/27),采用联合治疗后总体有效率为74.1%(20/27)。美罗培南单药治疗无效需联合治疗组患儿存在外科手术后开放性伤口(7/14 vs 1/13)、感染性休克(7/14 vs 1/13)、无菌体腔液(脑脊液及腹水)培养阳性(6/14 vs 0/13)、感染时需有创机械通气(10/14 vs 1/13)的患儿比例高于单药治疗有效组(P均<0.05),纸片扩散法药物敏感性试验中美罗培南抑菌圈直径小于单药治疗有效组[(9.14±3.37) mm vs (12.85±5.27) mm,P<0.05]。结论美罗培南单药治疗新生儿CRKP败血症具有一定疗效。当CRKP败血症患儿存在外科手术后开放性伤口、感染性休克、无菌体腔液培养阳性、感染时需有创机械通气及药物敏感性试验中美罗培南抑菌圈直径偏小时需联合治疗,以提高治疗有效率。
文摘This paper aims to estimate the soil organic carbon （SOC） storage in Northeast of China, identify its balance situation and changing trends under current cropping systems, and finally put forward some strategies to keep the SOC in balance. A biogeochemical model （DNDC） for agro-ecosystem was employed to predict SOC dynamics in agricultural ecosystems at regional scale. Data on climate, soil properties, cropping systems, acreage, and management practices at county scale were collected from various sources and integrated into a GIS database to support the model runs at the regional scale. The model predicted results revealed that （1） Total SOC storage in agricultural lands in Heilongjiang, Jilin and Liaoning provinces in Northeast of China is about 1 243.48 × 10^6 t （0-30cm soil layer）, respectively occupying 58.4, 25.5 and 16.1%; （2） Under the current cultivation systems, SOC is in a situation of net loss with carbon losing at a high rate of 31.22 × 10^6 t a^-1 （respectively 59.3, 25.9 and 14.8% in Heilongjiang, Jilin and Liaoning provinces） and 2.05 t ha^-1 a^-1, the situation is more serious in Heilongjiang and Jilin provinces; and （3） Protective cultivations, such as manuring, returning more residue of crop to the field, adopting no-till, are very useful for the accumulation of SOC in these regions.
