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通过式固相萃取柱/超高效液相色谱-串联质谱法同时测定水产养殖沉积物中磺胺类、喹诺酮类、四环素类22种抗生素兽药残留

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安徽化工 2024年第2期50卷 170-176页

作者：赵天珍宋海霞何国成梁莹宋长江中山市农产品质量安全检验所广东中山528400

目的:建立了同时测定水产养殖沉积物中22种抗生素的通过式固相萃取柱/超高效液相色谱-串联质谱法。方法:样品用8 mL EDTA-Mcllvaine-乙腈=4∶4超声提取,提取液过HLB通过式固相柱净化,UPLC-MS/MS检测,基质工作曲线和同位素内标法同时定... 详细信息

目的:建立了同时测定水产养殖沉积物中22种抗生素的通过式固相萃取柱/超高效液相色谱-串联质谱法。方法:样品用8 mL EDTA-Mcllvaine-乙腈=4∶4超声提取,提取液过HLB通过式固相柱净化,UPLC-MS/MS检测,基质工作曲线和同位素内标法同时定量。结果:在2.00~100μg/L范围内,22种抗生素的线性关系良好,相关系数均大于0.998。在10μg/kg、50μg/kg、100μg/kg这3个添加水平下,重复测定6次,回收率在60.3%~109.7%,相对标准偏差为1.2%~13.2%,符合GB/T 27404—2008对回收率和精密度的要求。结论:该方法高效快捷,准确可靠,适用于沉积物中抗生素类药物的快速测定。

关键词：超高效液相色谱-串联质谱法沉积物抗生素基质工作曲线同位素内标

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Inorganic nitrogen removal of toilet wastewater with an airlift external circulation membrane bioreactor

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Journal of Environmental Sciences 2007年第1期19卷 12-17页

作者： LI Gang WU Lin-lin DONG Chun-song WU Guang-xia FAN Yao-bo Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Removal of inorganic nitrogen （inorganic-N） from toilet wastewater, using a pilot-scale airlift external circulation membrane bioreactor （AEC-MBR） was studied. The results showed that the use of AEC-MBR with limited addition of alkaline reagents and volumetric loading rates of inorganic-N of 0.19-0.40 kg inorganic-N/（m^3·d） helped achieve the desired nitrification and denitrification. Furthermore, the effects of pH and dissolved oxygen （DO） on inorganic-N removal were examined. Under the condition of MLSS at 1.56-2.35 g/L, BODs/ammonia nitrogen （NH4＋-N） at 1.0, pH at 7.0-7.5, and DO at 1.0-2.0 mg/L, the removal efficiencies of NH4^＋-N and inorganic-N were 91.5% and 70.0%, respectively, in the AEC-MBR. The cost of addition of alkaline reagent was approximately 0.5-1.5 RMB yuan/m^3, and the energy consumption was approximately 0.72 kWh/m^3 at the flux of 8 L/（m^2-h）.

关键词： inorganic nitrogen removal treatment of wastewater from toilet airlift external circulation membrane bioreaetor (AECMBR) membrane bioreactor (MBR)

2018—2023年上海市15岁及以上居民膳食黄曲霉毒素暴露风险评估

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卫生研究 2024年第5期53卷 797-804页

作者：邱丹萍罗宝章蔡华杨京津秦璐昕宋夏徐碧瑶张楠刘弘上海市疾病预防控制中心上海200336

目的了解上海市售食品中黄曲霉毒素(aflatoxins,AFs)的污染现状及暴露水平。方法 2018—2023年在上海市采集8大类8114份样品,按照国家标准检测方法进行检测。结合“上海市居民膳食与健康状况监测”15岁及以上居民消费量数据,使用暴露... 详细信息

目的了解上海市售食品中黄曲霉毒素(aflatoxins,AFs)的污染现状及暴露水平。方法 2018—2023年在上海市采集8大类8114份样品,按照国家标准检测方法进行检测。结合“上海市居民膳食与健康状况监测”15岁及以上居民消费量数据,使用暴露限值法(margin of exposure,MOE)和人群肝癌发病风险法对AFs进行暴露风险评估。结果黄曲霉毒素B_(1)(aflatoxin B_(1),AFB_(1))、黄曲霉毒素B_(2)、黄曲霉毒素G_(1)、黄曲霉毒素G_(2)、黄曲霉毒素M_(1)的检出率分别为8.6%、2.0%、0.9%、0.2%和0.2%。点评估结果显示,上海市15岁及以上居民膳食中AFB_(1)总暴露量为0.783 ng/(kg·BW·d),其中谷类及其制品、坚果及其制品和植物油膳食暴露量占AFB_(1)的膳食暴露量贡献率分别为60.6%、25.0%和8.5%。黄曲霉毒素总量(total aflatoxins,AFT)的总暴露量为7.363 ng/(kg·BW·d),谷类及其制品、植物油、坚果及其制品膳食暴露量分别为占AFT的膳食暴露量贡献率分别为77.1%、8.4%和7.2%。概率评估结果显示,AFB_(1)和AFT的居民膳食平均暴露量分别为0.734和7.220 ng/(kg·BW·d),P95暴露量分别为1.170和11.500 ng/(kg·BW·d)。城郊结合区居民AFB_(1)暴露量高于中心城区和远郊地区(χ^(2)=16.357,P<0.001),中心城区居民的AFT暴露量低于城郊结合区和远郊地区(χ^(2)=40.996,P<0.001)。上海市15岁及以上居民AFB_(1)和AFT膳食平均暴露量的MOE值为511和54。上海市15岁及以上居民通过膳食摄入被AFB_(1)和AFT污染的食物引起肝癌的风险:0.024例/10万人、0.227例/10万人。结论上海市售食品中存在AFs污染,谷类及其制品、坚果及其制品、植物油是上海市15岁及以上居民膳食中AFs暴露的主要来源。

关键词：黄曲霉毒素膳食暴露风险评估食品

Analysis of choroidal morphology and comparison of imaging findings of subtypes of polypoidal choroidal vasculopathy:a new classification system

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International Journal of Ophthalmology(English edition) 2020年第5期13卷 731-736页

作者： Zi-Yang Liu Bing Li song xia You-Xin Chen Department of Ophthalmology Peking Union Medical College HospitalChinese Academy of Medical SciencesBeijing 100730China Department of Ophthalmology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Key Laboratory of Ocular Fundus Diseases Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100730China Department of Ophthalmology Guizhou Provincial People’s HospitalGuiyang 550002Guizhou ProvinceChina

AIM:To classify polypoidal choroidal vasculopathy(PCV)into 2 subtypes based on the subfoveal choroidal thickness(SFCT)and to further evaluate their multimodal image ***:A retrospective observational case series ***-four eyes of 64 patients with PCV were enrolled and classified into 2 groups based on SFCT(thick-choroid group/thin-choroid group).Then further analyze the spectrum domain optical coherence tomography(SD-OCT)and indocyanine green angiography(ICGA)differences of the two *** analysis included measurement of SFCT,maximum vascular diameter ratio(MVDR),choroidal vascularity index(CVI),central macular thickness(CMT),and the presence of pigment epithelial detachment(PED)on *** lesions(polyps)number,branching vascular network(BVN)area,greatest linear dimension(GLD),and the choroidal vascular hyperpermeability(CVH)were analyzed by ***:The distribution of SFCT was bimodal with two peaks at 195 and 285μm,and a trough at 225μ*** 225μm was taken as the cutoff point for the following classification of thick/thin choroid *** PCV eyes in the thick-choroid group presented with greater MVDR,CVI within 3 and 6 mm of the fovea,but lower CMT,less PED,small PED diameters on SD-OCT scans,and fewer polyps,smaller BVN and GLD,but more frequency of CVH on ***:The SFCT at 225μm can be used as a readily available indicator for the classification of PCV *** thick-choroid group presents much apparent enlargement of the choroidal layer and vasculature expansion,which indicates different pathogenesis of the two subtypes.

关键词： polypoidal choroidal vasculopathy spectral-domain optical coherence tomography indocyanine green angiography subfoveal choroidal thickness

Should few retrieved oocytes be as an indication for intracytoplasmic sperm injection?

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2012年第9期13卷 717-722页

作者： Qing-song XI Li-xia ZHU Juan HU Li WU Han-wang ZHANG Reproductive Medicine Center Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Objective:To reevaluate whether relatively few oocytes obtained in one cycle are an indication for intracytoplasmic sperm injection(ICSI).Methods:A total of 406 cycles with three or fewer retrieved oocytes performed in 396 non-male infertile couples were retrospectively *** were classified into three groups by different fertilization techniques:the in vitro fertilization(IVF) group,insemination with conventional IVF;the ICSI group,insemination with ICSI though semen parameters were normal;and the rescue ICSI group,re-insemination with ICSI after conventional IVF ***:The ICSI group resulted in higher normal fertilization compared with the conventional IVF ***,the cycle cancellation rate was decreased in the ICSI group,though it was not statistically *** clinical pregnancy rate and implantation rate were lower in the ICSI group compared with the conventional IVF *** ICSI was a method to avert total fertilization failure in conventional IVF,increasing fertilization and ensuring embryo availability for transfer,but the normal fertilization was the lowest due to delayed insemination and the chance of pregnancy was very ***:Obtaining only few oocytes in one cycle is not considered as an indication for ICSI when the sperm sample is apparently *** ICSI is either not recommended if conventional insemination *** patients should not be subjected to the unnecessary costs and potential risks of ICSI.

关键词： Fertilization rate Intracytoplasmic sperm injection (ICSI) Indication Oocyte number Patient age

Managing Procurement and Production Outsourcing under Dynamic Prices

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Acta Mathematicae Applicatae Sinica 2013年第1期29卷 135-142页

作者： xiao-gang CAO Chao YANG Hui WEN Huo-song xia Ji-zi LI School of Management Huazhong University of Science and Technology School of Management Wuhan Textile University School of Science Hubei University of Technology

This paper proposes a procurement and production outsourcing model subject to a dynamic prices environment. Using the optimal control theory we obtain the necessary conditions of the optimal procurement and production policy. From the study of optimal control conditions, we derive qualitative properties of the optimal procurement and production decisions for a few exemplifying cases. Through these results we are able to provide some managerial implications for managers to make real decisions.

关键词： production planning dynamic prices optimal control production outsourcing

Gene expression profile analyses of mice livers injured by Leigongteng

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World Journal of Gastroenterology 2007年第26期13卷 3619-3624页

作者： Yong Chen, xiao-Ming Zhang Feng-Mei Han Peng Du Qi-song xia Hubei Provincial Key Laboratory of Traditional Chinese Medicine & Biotechnology School of Life Science Hubei University Wuhan 430062 Hubei Province China

AIM： To analyze the gene expression profiles of mice livers injured by Leigongteng and explore the relationship between the differentially expressed genes and liver damage. METHODS： The experimental mice were randomly divided into a control group and a liver-injured group in which the mice were administrated 33 μγ, of triptolide/ kg per day for 30 d. Liver mRNAs were extracted from animals in both groups and were reverse-transcribed to cDNA with dUTP labeled by different fluorescence （Cy3, Cy5） as hybridization probes. The mixed probes were hybridized with oligonucleotide microarray chips. The fluorescent signal results were acquired by scanner and analyzed with software. RESULTS： Among the 35852 target genes, 29 genes were found to be significantly differentially expressed, with 20 genes up-regulated and 9 genes down-regulated. The reliability of the differentially expressed genes was validated by RT-PCR experiments of 5 randomly selected differentially expressed genes. CONCLUSION： Based on the biological functions of the differentially expressed genes, it is obvious that the occurrence and development of liver damage induced by Leigongteng in mice are highly associated with immune response, metabolism, apoptosis and the cell skeleton of liver cells. This might be important for elucidating the regulatory network of gene expression associated with liver damage and it may also be important for discovering the pathogenic mechanisms of liver damage induced by Leigongteng.

关键词： Tripterygium Wilfordii Hook.f. Gene expre-ssion profile Oligonucleotide microarray Mice

Intergenic spacer 1(IGS1) polymorphism map: A marker for the initial classification of cultivated Lentinula edodes strains in China

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Journal of Integrative Agriculture 2018年第11期17卷 2458-2466页

作者： song xiao-xia ZHAO Yan song Chun-yan LI Chuan-hua CHEN Ming-jie HUANG Jian-chun TAN Qi Institute of Edible Fungi Shanghai Academy of Agricultural Sciences

China is currently the world＇s leading producer of Lentinula edodes and owns many cultivated strains of this species. This study was performed in order to investigate intergenic spacer I （IGS1） polymorphism and classification among 49 popular cultivated strains. The great majority of the 49 strains possessed two different IGS1 sequences, with distinct lengths and homologies. Based on the length and homology of the IGS1 sequences of the 49 strains, the strains were classified into two groups： A and B. Group A was subdivided into six subgroups. Forty-seven strains were homozygous or heterozygous among these six subgroups in group A, Cr01 was heterozygous between A and B, and Guangxiang 9 was homozygous in group B. An IGS1 polymorphism map of each cultivated L. edodes strain is reported for the first time and could be used as a marker for the initial classification and management of cultivated L. edodes strains in China.

关键词： Lentinula edodes strain intergenic spacer polymorphism genotype

An Elliptic Centerness for Object Instance Segmentation in Aerial Images

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Journal of Remote Sensing 2022年第1期2022卷 182-195页

作者： Yixin Luo Jiaming Han Zhou Liu Mi Wang Gui-song xia LIESMARS Wuhan UniversityWuhanChina School of Computer Science Wuhan UniversityWuhanChina

Instance segmentation in aerial images is an important and challenging *** of the existing methods have adapted instance segmentation algorithms developed for natural images to aerial ***,these methods easily suffer from performance degradation in aerial images,due to the scale variations,large aspect ratios,and arbitrary orientations of instances caused by the bird’s-eye view of aerial *** address this issue,we propose an elliptic centerness(EC)for instance segmentation in aerial images,which can assign the proper centerness values to the intricate aerial instances and thus mitigate the performance ***,we introduce ellipses to fit the various contours of aerial instances and measure these fitted ellipses by two-dimensional anisotropic Gaussian *** with EC,we develop a one-stage aerial instance segmentation *** experiments on a commonly used dataset,the instance segmentation in aerial images dataset(iSAID),demonstrate that our proposed method can achieve a remarkable performance of instance segmentation while introducing negligible computational cost.

关键词： instance negligible fitted