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991.
All kinds of industries can produce a large amount of the heavy metal Mn emission, especially in the Mn steel plant production process. The assessment of Mn pollution in industrial areas is vital to human health and soil conservation. First, there are 120 samples of 0–5 cm and samples 9 of 0–40 cm of the surface soil collected from outside. Next, the soil column test is applied to study the migration and speciation regularity of Mn in 0–40 cm of soil layer, and then a forecasting model is established to verify and evaluate the Mn pollution in the study area. After the exogenous Mn enters the soil, Mn soon transforms into a more stable form in soil at 0–20 cm depth. But the residual amounts of Mn in deep soil increases with the increase of exogenous Mn. The main speciation of Mn in surface soil includes residual, oxide-bound, and organic-bound forms. Carbonate-bound form is sensitive to the increase of exogenous Mn. The exogenous Mn content has less influence on the content of oxide-bound and organic-bound forms in soils below 20 cm. The prediction model can be used to evaluate the degree of pollution of Mn in surface soil of the study area. 相似文献
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993.
994.
Jeffrey H. Stern Yangzi Tian James Funderburgh Graziella Pellegrini Kang Zhang Jeffrey L. Goldberg Robin R. Ali Michael Young Yubing Xie Sally Temple 《Cell Stem Cell》2018,22(6):834-849
995.
Liwen Zhang Bojiang Chen Xia Liu Jiangdian Song Mengjie Fang Chaoen Hu Di Dong Weimin Li Jie Tian 《Translational oncology》2018,11(1):94-101
OBJECTIVES: To predict epidermal growth factor receptor (EGFR) mutation status using quantitative radiomic biomarkers and representative clinical variables. METHODS: The study included 180 patients diagnosed as of non-small cell lung cancer (NSCLC) with their pre-therapy computed tomography (CT) scans. Using a radiomic method, 485 features that reflect the heterogeneity and phenotype of tumors were extracted. Afterwards, these radiomic features were used for predicting epidermal growth factor receptor (EGFR) mutation status by a least absolute shrinkage and selection operator (LASSO) based on multivariable logistic regression. As a result, we found that radiomic features have prognostic ability in EGFR mutation status prediction. In addition, we used radiomic nomogram and calibration curve to test the performance of the model. RESULTS: Multivariate analysis revealed that the radiomic features had the potential to build a prediction model for EGFR mutation. The area under the receiver operating characteristic curve (AUC) for the training cohort was 0.8618, and the AUC for the validation cohort was 0.8725, which were superior to prediction model that used clinical variables alone. CONCLUSION: Radiomic features are better predictors of EGFR mutation status than conventional semantic CT image features or clinical variables to help doctors to decide who need EGFR tyrosine kinase inhibitor (TKI) treatment. 相似文献
996.
Chen Shen Zhenyu Liu Zhaoqi Wang Jia Guo Hongkai Zhang Yingshu Wang Jianjun Qin Hailiang Li Mengjie Fang Zhenchao Tang Yin Li Jinrong Qu Jie Tian 《Translational oncology》2018,11(3):815-824
PURPOSE: To build and validate a radiomics-based nomogram for the prediction of pre-operation lymph node (LN) metastasis in esophageal cancer. PATIENTS AND METHODS: A total of 197 esophageal cancer patients were enrolled in this study, and their LN metastases have been pathologically confirmed. The data were collected from January 2016 to May 2016; patients in the first three months were set in the training cohort, and patients in April 2016 were set in the validation cohort. About 788 radiomics features were extracted from computed tomography (CT) images of the patients. The elastic-net approach was exploited for dimension reduction and selection of the feature space. The multivariable logistic regression analysis was adopted to build the radiomics signature and another predictive nomogram model. The predictive nomogram model was composed of three factors with the radiomics signature, where CT reported the LN number and position risk level. The performance and usefulness of the built model were assessed by the calibration and decision curve analysis. RESULTS: Thirteen radiomics features were selected to build the radiomics signature. The radiomics signature was significantly associated with the LN metastasis (P<0.001). The area under the curve (AUC) of the radiomics signature performance in the training cohort was 0.806 (95% CI: 0.732-0.881), and in the validation cohort it was 0.771 (95% CI: 0.632-0.910). The model showed good discrimination, with a Harrell’s Concordance Index of 0.768 (0.672 to 0.864, 95% CI) in the training cohort and 0.754 (0.603 to 0.895, 95% CI) in the validation cohort. Decision curve analysis showed our model will receive benefit when the threshold probability was larger than 0.15. CONCLUSION: The present study proposed a radiomics-based nomogram involving the radiomics signature, so the CT reported the status of the suspected LN and the dummy variable of the tumor position. It can be potentially applied in the individual preoperative prediction of the LN metastasis status in esophageal cancer patients. 相似文献
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998.
Hewei Zhang Mingqi Xia Wei Wang Decai Ju Long Cao Bai Wu Xin Wang Ying Wu Ni Song Jiaxin Hu Changxiao Tian Shucheng Zhang Hua Wu 《中国病毒学》2018,33(2):153-161
A novel PRRSV strain was isolated in China that was genetically similar to the NADC30 strain which is reported to have spread throughout China. The objective of the present study was to evaluate the cross-protective efficacy of the live vaccine TJM-F92 in young pigs against challenge with a NADC30-like strain, HN201605. Twenty-five PRRSV- and antibody-free pigs were randomly divided into the following five groups: Vac/ChA, Unvac/ChA, Vac/ChB, Unvac/ChB and the mock. The pigs in groups Vac/ChA and Vac/ChB were inoculated intramuscularly with 1 mL TJM-F92 (105.0 TCID50/mL). At 28 days post vaccination (0 days post challenge), groups Vac/ChA and Unvac/ChA were inoculated intranasally with 104.5 TCID50/mL PRRSV strain TJ F3 (2 mL/pig), while groups Vac/ChB and Unvac/ChB were inoculated, using the same route, with the same dose of the NADC30-like strain HN201605 F3. Protective effects of the PRRSV strain were observed in all pigs in the Vac/ChA and Vac/ChB groups. Neither high fever nor signs of clinical disease were observed through the experiment in these groups, whereas pigs in Unvac/ChA group exhibited serious clinical symptoms, pathological lesions, and weight loss. In Unvac/ChB group, pigs developed milder clinical symptoms, which demonstrated that the NADC30-like strain HN201605 had moderate pathogenicity. The results suggest that the MLV vaccine strain TJM-F92 is an effective and safe vaccine candidate for use in China. 相似文献
999.
正Cotton is not only an important cash crop for its fiber,but also an excellent model system for studying polyploidization,cell elongation and cell wall biosynthesis(Yang et al.,2014;Fang et al.,2017;Wang et al.,2016;Zou et al.,2016).A focus for scientists is to dissect the genetic basis underlying important agronomic traits(Gong et al.,2018;Huang et al.,2016).The advent of high-throughput sequencing technologies has boosted unveiling the cotton genome(Wang et al.,2012;Li et al.,2014;Li et al.,2015).High-throughput 相似文献
1000.
Two experiments were conducted to evaluate the digestible (DE) and metabolisable energy (ME), apparent (AID) and standardised ileal digestibility (SID) of amino acids (AA) in yeast extract (YE) and spray-dried porcine plasma (SDPP). In Experiment 1, 18 barrows (25.1 ± 1.2 kg body weight [BW]) were randomly allotted to three treatments with six replicates per treatment. The DE and ME of YE was 20.64 and 19.31 MJ/kg, respectively, which were not significantly different with the DE and ME of SDPP (18.74 and 18.05 MJ/kg, respectively). In Experiment 2, six barrows (20.6 ± 2.6 kg BW) fitted with ileal T-cannulas were fed three diets in a repeated 3-period Latin square design. For Met and Glu, the AID tended to be, while the SID was significantly higher (p < 0.05), in YE than in SDPP. The AID of Cys tended to be lower in YE (p = 0.07), while the SID of Phe tended to be higher in YE than in SDPP (p = 0.06). Accordingly, YE could be a potential substitute for SDPP as a superior protein ingredient in diets for pigs in terms of the available energy and AA digestibility. 相似文献