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Research progress on secondary formation,photosensitive reaction mechanism and human health effects of chromophoric brown carbon
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作者 Baihang Chen Jiangyao Chen +1 位作者 Guiying Li Taicheng An 《Journal of Environmental Sciences》 2025年第5期310-330,共21页
Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a phy... Brown carbon(BrC)has attracted widespread attention because of its strong absorption of solar radiation in the ultraviolet-visible wavelength range,which causes adverse impacts on human health.Originally,BrC was a physically defined class of substances.However,current research has gradually shifted towards the identification of its chemical groups,because its light-absorbing capability,chemical properties and health effects mainly depend on the chemical composition of its chromophores.Therefore,this review mainly focuses on the chemical understanding of BrC based on chromophores,and the secondary formation mechanism of chromophores,photosensitized reactions,and human health effects of BrC were detailly summarized.Firstly,BrC chromophores are divided into five categories:nitrogen-heterocycles,nitrogen-chain,aromatic species,oligomers and sulfur-containing organic compounds.Different chromophore precursor species exhibit variations,and their formation mechanisms are also distinct.Secondly,BrC can trigger the production of secondary organic aerosol(SOA)precursors or cause SOA growth because BrC is an important component of light-absorbing particles formed during incomplete combustion of biomass and fossil fuels,potentially exerting adverse effects on human health.Finally,developing sufficiently separated methods for BrC and refining algorithms and machine learning can lead to a more effective understanding of the chemical composition of chromophores,thus enabling better evaluation of the atmospheric effects and health impacts of BrC.In all,this review provides new insights into the categories of BrC chromophores and new advance in secondary formation mechanisms,photosensitized reactions,and human health effects on the basis of chemical structures. 展开更多
关键词 Brown carbon Constituent characteristics Secondary formation mechanism PHOTOSENSITIVE human health effects
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Cloning,Eukaryotic Expression of Human ISG20 and Preliminary Study on the Effect of Its Anti-HBV 被引量:3
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作者 郝友华 杨东亮 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2008年第1期11-13,共3页
Human ISG20 gene was cloned and the effect of its anti-HBV was primarily studied. The ISG20 gene was amplified from HeLa cells by RT-PCR and recombinant vector expressing ISG20 was constructed by genetic engineering. ... Human ISG20 gene was cloned and the effect of its anti-HBV was primarily studied. The ISG20 gene was amplified from HeLa cells by RT-PCR and recombinant vector expressing ISG20 was constructed by genetic engineering. The overexpression of ISG20 in HepG2 cells was detected by Western blot and the levels of secretion of HBs antigen and HBe antigen tested by ELISA. The results showed that: (1) Sequence of ISG20 cloned was consistent to that published in Genebank; (2) Recombinant vector expressing ISG20 could be expressed in HepG2 cells by transfection; (3) The overexpression of ISG20 protein could reduce the levels of the secretion of HBs antigen and HBe antigen in transfected HepG2 cells. It was suggested that the overexpression of recombinant ISG20 in culture cells could reduce the synthesis of HBV proteins. 展开更多
关键词 human ISG20 effect of anti-HBV
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Polyphenols in Fruits and Vegetables and Its Effect on Human Health 被引量:2
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作者 Giuseppina Pace Pereira Lima Fabio Vianello +2 位作者 Camila Renata Corrêa Renê Arnoux da Silva Campos Milena Galhardo Borguini 《Food and Nutrition Sciences》 2014年第11期1065-1082,共18页
Polyphenols represent a group of chemical substances common in plants, structurally characterized by the presence of one or more phenol units. Polyphenols are the most abundant antioxidants in human diets and the larg... Polyphenols represent a group of chemical substances common in plants, structurally characterized by the presence of one or more phenol units. Polyphenols are the most abundant antioxidants in human diets and the largest and best studied class of polyphenols is flavonoids, which include several thousand compounds. Numerous studies confirm that they exert a protective action on human health and are key components of a healthy and balanced diet. Epidemiological studies correlate flavonoid intake with a reduced incidence of chronic diseases, such as cardiovascular disease, diabetes and cancer. The involvement of reactive oxygen species (ROS) in the etiology of these degenerative conditions has suggested that phytochemicals showing antioxidant activity may contribute to the prevention of these pathologies. The present review deals with phenolic compounds in plants and reports on recent studies. Moreover, the present work includes information on the relationships between the consumption of these compounds, via feeding, and risk of disease occurrence, i.e. the effect on human health. Results obtained on herbs, essential oils, from plants grown in tropical, subtropical and temperate regions, were also reported. 展开更多
关键词 FRUITS VEGETABLES Consume effect on human Phenolic Content Thermal Processing ABSORPTION
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The Effect of Foods Containing Refined Konjac Meal on Human Lipid Metabolism 被引量:4
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作者 ZHANG MAO-YU, HUANG CHENG-YU, WANG XU, HONG JUN-RONG,AND PENG SHU-SHEN Department of Nutrition and Food Hygiene, West China University of Medical Sciences, Chengdu, Sichuan, China 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1990年第1期99-105,共7页
A total of 110 elderly people with hyperlipidemia were randomly assigned to one of two groups. The experimental group consumed an ordinary diet plus foods containing refined Konjac meal, and the control group consumed... A total of 110 elderly people with hyperlipidemia were randomly assigned to one of two groups. The experimental group consumed an ordinary diet plus foods containing refined Konjac meal, and the control group consumed only the ordinary diet. The experiment was carried out for 45 days. The results indicate that for the experimental group blood levels of triglyeendes (TG), total cholesterol (TC), and low-density lipoprotein cholesterol (LDL-C) were significantly lowered (P < 0.01) at the end of the trial, whereas high-density lipoprotein cholesterol (HDL-C) and apoprotein (Al) levels were significantly elevated (P<0.01). In contrast, for the control group, the changes in the above parameters were insignificant. The differences in TC. TG, LDL-C, and HDL-C levels between the two groups were statistically significant. The effects of refined Konjac meal on lipid levels in the blood were somewhat different between patients with hyperlipidemia and subjects with risk critical values only. For the former, TG and TC were decreased by 83.8±133.5 mg/dl, and 42.4±23.4 mg/dl. respectively: but for the latter, they are decreased only by -1.1±23.1 mg/dl and 8.3± 18.2 mg/dl, respectively; the difference mentioned above is Statistically significant (P<0.01). 1990 Academic Press. Inc. 展开更多
关键词 The effect of Foods Containing Refined Konjac Meal on human Lipid Metabolism
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Anti-tumor Effects of a Recombinant Fowlpox Virus Expressing Apoptin on Human Cervical Carcinoma in Vivo and in Vitro 被引量:3
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作者 ZHU Ji-hong LI Xiao +7 位作者 SUN Li-li ZHANG Mu-chun KAN Shi-fu LIU Lei HUANG Hai-yan YANG Guo-hua PIAO Bing-guo JIN Ning-yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第4期646-650,共5页
Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore t... Apoptin is a chicken anemia virus-derived,p53-independent,bcl-2-insensitive apoptotic protein with the ability to specifically induce apoptosis of various human tumor cells,but not of normal diploid cells.To explore the application of apoptin in tumor gene therapy,we used a recombinant fowlpox virus expressing apoptin protein (vFV-Apoptin) to investigate the anti-tumor effectes of vFV-Apoptin on human cervical carcinoma(HeLa) cells in vivo and in vitro through 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide(MTT) assay,acridine orage/ethidium bromide(AO/EB) and annexin V staining test,respectively.The results show that vFV-Apoptin inhibites the proliferation of HeLa cells in vitro through inducing the apoptosis of HeLa cells,and the inhibition effect of vFV-Apoptin has a dose-effect and time-effect relationship.The results of animal models show that vFV-Apoptin significantly inhibits tumor growth,extends the lifespan of animals and improves the mean survival.Experimental results indicate that vFV-Apoptin has a potential application in the tumor gene therapy. 展开更多
关键词 Apoptin gene Chicken anemia virus human cervical carcinoma Anti-tumor effect
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ANTI-HUMAN LUNG GIANT CELL CANCER (PG) EFFECT OF HUMAN LAK CELLS IN VITRO AND IN NUDE MICE
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作者 邓鸿业 丁桂凤 +3 位作者 邓玉兰 方伟岗 吴秉铨 孙靖 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第2期30-32,共3页
Human LAK cells were prepared by culturing normal human peripheral blood mononuclear cells (PBMC) with or without rIL-2 and assayed for T cell surface markers as well as anti-tumor activity against PC in vitro and in ... Human LAK cells were prepared by culturing normal human peripheral blood mononuclear cells (PBMC) with or without rIL-2 and assayed for T cell surface markers as well as anti-tumor activity against PC in vitro and in nude mice. Although the percentages of T3, T4, and T8 positive cells in rIL-2-activated cells did not differ significantly from those of control cells in vitro, the former showed stronger cytotoxicity than control cells to PG tumor cells in vitro. In vivo, LAK cells completely inhibited the growth of PG tumor in nude mice, whereas PBMC control cells were to be of no effect. The anti-tumor effect of human LAK cells in nude mice may offer a useful model to study the role of human LAK cells against human tumor in vivo. 展开更多
关键词 LAK effect OF human LAK CELLS IN VITRO AND IN NUDE MICE ANTI-human LUNG GIANT CELL CANCER PG
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Effects of Spinach Powder Fat-Soluble Extract on Proliferation of Human Gastric Adenocarcinoma Cells 被引量:2
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作者 HETAO HUANGCHENG-YU 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第4期247-252,共6页
Four kinds of assays were used to study the effect of a fat-soluble extract of spinach powder (SPFE) on the proliferation of human gastric adenocareinoma cell line (SGC-7901) in vitro.These studies included: (Ⅰ) cell... Four kinds of assays were used to study the effect of a fat-soluble extract of spinach powder (SPFE) on the proliferation of human gastric adenocareinoma cell line (SGC-7901) in vitro.These studies included: (Ⅰ) cell growth assay, (Ⅱ) colony forming assay, (Ⅲ) MTT colorimetric assay, and (Ⅳ) 3H-TdR incorporation assay. The concentrations of SPFE expressed as the level of β-carotene in the medium were 2×10-8, 2×10-7 and 2×10-6 mol/L β-carotene in assays (Ⅰ)~(Ⅲ), but 4×10- 8, 4×10-7 and 4×10-6 mol/L β-caretene in assay (Ⅳ) respectively. The results indicated that SPFE inhibited the prolifendion and colony forming ability of SGC-7901 cells. And in MTT assay, SPFE inhibited the viability of SGC7901 cells, but no inhibitory effect of SPFE was observed on the viability of lymphocytes in peripheral blood of healthy people. Finally, in the 3H-TdR incorporation test, both SPFE and β-carotene showed significant inhibitory effects on DNA synthesis in SGC-7901 cells, but SPFE was more effective than β-carotene. 展开更多
关键词 SGC Chen cell line effects of Spinach Powder Fat-Soluble Extract on Proliferation of human Gastric Adenocarcinoma Cells
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Relaxant Effects of Quercetin and Rutin on Human Isolated Bronchus 被引量:1
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作者 Hanifa Djelili Lekhmici Arrar +1 位作者 Emmanuel Naline Philippe Devillier 《Chinese Medicine》 2012年第2期94-100,共7页
Increasing epidemiological evidence supports the view, that quercetin has protective roles in a multitude of disease states in human who have a high intake of polyphenols. To investigate the ability of quercetin and i... Increasing epidemiological evidence supports the view, that quercetin has protective roles in a multitude of disease states in human who have a high intake of polyphenols. To investigate the ability of quercetin and its rutinoside, rutin, to modulate the relaxation of human airways smooth muscle and to determine the mechanism (s) of such relaxation, isolated human bronchus rings were suspended in individual organ baths, precontracted with acetylcholine or with histamine and the relaxing effects of quercetin and rutin were determined by measurement of isometric tension. Quercetin induced concentration-dependent relaxant responses on acetylcholine or histamine precontracted human bronchial rings and with almost equal effectiveness. In terms of potency (pD2) and efficacy (Emax), quercetin is more potent than rutin on relaxant responses of human bronchus. K+ and Ca2+ concentration-dependent contraction curves were inhibited after incubation with increasing concentrations of quercetin. Quercetin potentiated in a concentration-dependent manner the relaxant effects of isoprenaline or sodium nitroprusside. Rutin had no effect on K+-induced contraction and on relaxant activity of isoprenaline or sodium nitroprusside. Our results suggest that the bronchodilator effects of quercetin are modulated by an increase in cyclic nucleotide levels as well as an alteration in availability of Ca2+ to the contractile machinery. 展开更多
关键词 Calcium Channels Cyclic NUCLEOTIDE human BRONCHUS QUERCETIN Relaxant effectS RUTIN
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REGULATORY EFFECTS OF HUMAN RECOMBINANT IL-6 ON NATURAL KILLER CELL ACTIVITY OF HUMAN FETAL SPLEENS
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作者 路力生 崔正言 田志刚 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第1期38-41,共4页
In the present study it was proved first that human recombinant interleukin-6(HrIL-6) significantly augmented natural killer(NK) cell activity derived from human fetal spleens against K562 target cells in a 4 hours 51... In the present study it was proved first that human recombinant interleukin-6(HrIL-6) significantly augmented natural killer(NK) cell activity derived from human fetal spleens against K562 target cells in a 4 hours 51Cr release assay. The enhancement of NK activity with 24 hours preincubation in HrlL-6 was dose-dependent, and significantly higher than that of fresh NK cells and controls cultured with RPMI-1640 medium alone (P<0.001). We also found that IL-6 was able to augment NK activity from different fetal spleens at 20 to 40 weeks of gestation (up to 2.24 to 2.78 times), and no difference of NK activity of fetal splenocytes treated by HrIL-6 was observed between different fetal age (32.3% to 45.4%, P>0.05). Furthermore, IL-6-augmented NK activity of fetal splenocytes was very similar to adult levels (P>0.05). These finding strongly indicated that IL-6 plays an important role in the development of NK cell function during the gestational period, suggesting that IL-6 may be of importance in the regulation of host defense mechanisms against malignancies and viral diseases. 展开更多
关键词 IL REGULATORY effectS OF human RECOMBINANT IL-6 ON NATURAL KILLER CELL ACTIVITY OF human FETAL SPLEENS
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Lethal effect of mononuclear cells derived from human umbilical cord blood differentiating into dendritic cells after in vitro induction of cytokines on neuroblastoma cells 被引量:1
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作者 Zhenghai Qu Jianxin Zuo +1 位作者 Lirong Sun Xindong Qu 《Neural Regeneration Research》 SCIE CAS CSCD 2006年第3期217-220,共4页
BACKGROUND: Dendritic cell is the most major antigen presenting cell of organism. It is proved in recent studies that human umbilical cord blood mononuclear cells induced and cultured in vitro by recombinant human gr... BACKGROUND: Dendritic cell is the most major antigen presenting cell of organism. It is proved in recent studies that human umbilical cord blood mononuclear cells induced and cultured in vitro by recombinant human granulocyte-macrophage colony stimulating factor (rhG-MCSF) and recombinant human interleukin-4 (rhlL-4) can generate a great many dendritic cells and promote the lethal effect of T cells on human neuroblastoma, but it is unclear that whether the lethal effect is associated with the most proper concentration of dendritic cells. OBJEETIVE: To investigate the lethal effect of human umbilical cord blood mononuclear cells induced in vitro by cytokines differentiating into dendritic cells on human neuroblastoma, and its best concentration range. DESIGN : Open experiment SEI-FING: Department of Pediatrics, the Medical School Hospital of Qingdao University MATERIALS : The study was carried out in the Shandong Provincial Key Laboratory (Laboratory for the Department of Pediatrics of the Medical School Hospital of Qingdao University) during September 2005 to May 2006. Human umbilical cord blood samples were taken from the healthy newborn infants of full-term normal delivery during October to November 2005 in the Medical School Hospital of Qingdao University, and were voluntarily donated by the puerperas. Main instruments: type 3111 CO2 incubator (Forma Scientific, USA), type 550 ELISA Reader (Bio-Rad, USA). Main reagents: neuroblastoma cell line SK-N-SH (Shanghai Institute of Life Science, Chinese Academy of Sciences), RPMI-1640 culture fluid and fetal bovine serum (Hyclone), rhlL-4 (Promega, USA), rhG-MCSF (Harbin Pharmaceutic Group Bioengineering Co.Ltd), rat anti-human CDla monoclonal antibody and FITC-labeled rabbit anti-rat IgG (Xiehe Stem cell Gene Engineering Co.Ltd). METHODS: ① Human umbilical cord blood mononuclear cells obtained with attachment methods differentiated into human umbilical cord blood dendritic cells, presenting typical morphology of dendritic cells after in vitro induction by rhG-MCSF and rhlL-4. ② Different concentrations of dendritic cells[ dendritic cells: neuroblastoma cells=20:1,50:1,100:1 (2×10^8 L^-1,5×10^8 L^-1,1×10^9 L^-1)], 1×10^9 L^-1 T cells and 1×10^7 L^-1 neuroblastoma cells were added in the experimental group. 1 ×10^9 L^-1 T cells and 1 ×10^7 L^-1 neuroblastoma cells were added in the control group. ③ Main surface marker CDla molecules of dendritic cells were detected with indirect immunofluorescence, and the percent rate of dendritic cells was counted with ultraviolet light and expressed as the expression rate of CD1a^+ cells. ④Single effector cells and target cells were respectively set in the experimental group and control group to obtain the lethal effect. The lethal effect of dendritic cells on neuroblastoma cells was indirectly evaluated by detecting cellular survival with MTT assay. The lethal effect(%)= (1-A experimentat well-A effector cell /A target cell well)×100%.⑤The expenmental data were presented as Mean ±SD, and paired t test was used. MAIN OUTCOME MEASURES: ① Morphological characters of dendritic cells in the process of induction and differentiation. ②CD1a^+ cellular expression rate. ③Lethal effect of dendntic cells on neuroblastoma cells. RESULTS: ①Morphological characters of dendritic cells in the process of induction and differentiation: On the 15^th day after human umbilical cord blood mononuclear cells were induced by rhG-MCSF and rhlL-4, typical morphology of dendritic cells could be seen under an inverted microscope. ②Expression rate of CD1a^+ cells was (43.12±5.83)%. ③Lethal effect of dendritic cells on neuroblastoma cells: Lethal effect of dendritic cells stimulated T cells in each experimental group ( dendritic cells: neuroblastoma cells=100:1,50:1, 20:1 respectively) on neuroblastoma cells was significantly higher than that in control group[(31.00 ±4.41 )%, (30.92±5.27)%,(33.57±5.35)%,(26.23±5.20)%, t=3.51,2.98,4.24, P〈 0.01 ); But the lethal effect of dendntic cells on neuroblastoma was significantly lower when their ratio was 100:1 and 50:1 in comparison with 20:1 (t=2.01,2.36, P 〈 0.05), and no significant difference in lethal effect existed between the ratio at 100:1 and 50:1 (t=0.06,P 〉 0.05). CONCLUSION: Dendritic cells differentiated from human umbilical cord blood mononuclear cells after in vitro induction of cytokines can promote the lethal effect of T cells on neuroblastoma cells. The lethal effect is associated with the concentration of dendritic cells within some range. 展开更多
关键词 CELL Lethal effect of mononuclear cells derived from human umbilical cord blood differentiating into dendritic cells after in vitro induction of cytokines on neuroblastoma cells
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The Effects of Reverse Transcriptase Inhibitor on Radiosensitization of Human Malignant Glioma Cells
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作者 Jing DAI Fu-Xiang ZHOU Cong-Hua XIE Zhi-Guo LUO Yun-Feng ZHOU~Δ(Department of Radio-Chematherapy of Zhongnan Hospital and Cancer Research Center, Wuhan University, Wuhan 430071, China) 《生物医学工程学杂志》 EI CAS CSCD 北大核心 2005年第S1期121-122,共2页
关键词 The effects of Reverse Transcriptase Inhibitor on Radiosensitization of human Malignant Glioma Cells DSB AZT
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EFFECTS OF PSEUDOFYPE RETROVIRUS CONTAINING HUMAN N-RAS ANTISENSE GENE ON THE GROWTH OF HUMAN LIVER CANCER LTNM4 TRANSPLANTED IN NUDE MICE
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作者 许秀兰 贾立斌 +5 位作者 郑亚海 干晨 顾健人 张素胤 陈陵际 殳裕华 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1991年第2期25-29,共5页
An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarci... An amphotropic pseudotype retrovirus containing human N-ras antisense gene was constructed and packaged with helper cells. It has been previously demonstrated that the virus did inhibit the growth of human hepatocarcinoma cell line PLC PRF/5 in vitro accompanied with the blockage of p21 expression. Based on these results, further study was carried on to examine the effect of these viruses on the growth of human hepatoma transplanted LTNM4 in nude mice. It has been shown that the retrovirus containing human antisense N-ras gene could inhibit the hepatoma in nude mice at a rate of 78% (P<0.05) as compared with saline control. No inhibition was observed in group treated with retrovirus which contained no N-ras sequence. These results in vivo lend further support that human N-ras antisense gene mediated by retrovirus could block the expression of the relevant oncogene and lead to the inhibition of cancer growth. It also provided the basis for further approaches of gene therapy for human cancer. 展开更多
关键词 RNA effectS OF PSEUDOFYPE RETROVIRUS CONTAINING human N-RAS ANTISENSE GENE ON THE GROWTH OF human LIVER CANCER LTNM4 TRANSPLANTED IN NUDE MICE gene
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企业智能化转型提升了劳动力投资效率吗? 被引量:3
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作者 刘慧凤 杨来峰 《山东大学学报(哲学社会科学版)》 北大核心 2025年第2期133-145,共13页
智能化转型升级作为企业技术进步的手段,理论上面临着“稳增长”和“稳就业”冲突的挑战。基于手工整理实施智能化转型企业名单,研究企业智能化转型对劳动力投资效率的影响及其作用机制,旨在检验在保就业任务下,企业智能化转型能否兼顾... 智能化转型升级作为企业技术进步的手段,理论上面临着“稳增长”和“稳就业”冲突的挑战。基于手工整理实施智能化转型企业名单,研究企业智能化转型对劳动力投资效率的影响及其作用机制,旨在检验在保就业任务下,企业智能化转型能否兼顾劳动力投资效率的提升,研究发现,信息效应和人力资本效应是智能化转型提升企业劳动力投资效率的潜在路径。并且,智能化转型在抑制企业劳动力投资过度的同时,也有助于缓解企业的劳动力投资不足,但智能化转型没有显著改善国有企业劳动力投资过度问题。研究表明,推动企业智能化转型,利用智能制造为企业赋能,可以同时实现“稳增长”和“稳就业”的高质量发展目标。 展开更多
关键词 智能化转型 劳动力投资效率 信息效应 人力资本效应 稳就业
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Apoptotic Effect of Cryptotanshinone on Human Melanoma A375 Cells
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作者 Jinqian LI Jiaru WANG +9 位作者 Lingqi MENG Yi ZHANG Hao WANG Wanting XU Yang LIU Yu ZHANG Shinong WANG Yuqing ZHAI Yinghua LUO Chenghao JIN 《Medicinal Plant》 CAS 2018年第6期39-42,共4页
[Objectives] The aim was to investigate the effect of cryptotanshinone on apoptosis of human melanoma A375 cells and its related mechanism of mitochondrial pathway.[Methods]The cytotoxic effect of cryptotanshinone on ... [Objectives] The aim was to investigate the effect of cryptotanshinone on apoptosis of human melanoma A375 cells and its related mechanism of mitochondrial pathway.[Methods]The cytotoxic effect of cryptotanshinone on apoptosis of human melanoma A375 cells was detected by MTT colorimetry.The apoptosis of melanoma A375 cells was detected with Annexin V-FITC/PI and observed by fluorescence inverted microscope.The expression of apoptosis-related proteins was detected by Western blotting.[Results]The viability of the A375 cells decreased with the increase of drug concentration.The fluorescence intensity of the cells increased with the treatment time.The expression of pro-apoptotic protein caspase-3 gradually increased,while the expression of apoptosis-inhibiting proteins p-AKT and Bcl-2 gradually reduced.[Conclusions]Cryptotanshinone induces apoptosis of human melanoma A375 cells via AKT signaling pathway,thus exerting a good cytotoxic effect on A375 cells. 展开更多
关键词 CRYPTOTANSHINONE human MELANOMA A375 cells CYTOTOXIC effect Apoptosis AKT signaling pathway
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Cloning and expression of human arresten gene and effect of its recombinant protein on endothelial cell proliferation
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作者 宋自芳 《外科研究与新技术》 2005年第3期171-172,共2页
To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites ... To clone human arresten gene and investigate biological activity of the recombinant protein.Methods Human arresten gene was obtained from the plasmid pGEMArr and subcloned into the BamHⅠ and Pst Ⅰ restriction sites of prokaryotic expression vector pRSET containing T7 promoter.The recombinant plasmid pRSETAN was subsequently transformed into the strain E.coli BL21(DE3),and the target gene was expressed under induction of IPTG.The expressed protein was extracted,purified by Ni 2+ chelation affinity chromatography and refoled.The effect of the recombinant protein on proliferation of human umbilical vein endothelial cells (HUVECs) was also analyzed with the MTT assay.Results Endonuclease digesting and DNA sequencing confirmed that the arresten gene was correctly inserted into the expression vector.The recombinant protein was hightly expressed in the form of inclusion body in the host bacteria after induction.SDS-PAGE analysis revealed that the recombinant protein with a molecular weight of 26×103 amounted to 27% of the total bacterial proteins.The purity of the expected protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could reach over 96% through affinity chromatography.After renaturation,the recombinant protein could significantly suppress proliferation of human umbilical vein endothelia cells(HUVECs) induced by vascular endothelial growth factor(VEGF).Conclusion Human arresten gene was successfully cloned into the expression vector pRSET and expressed at high level in Escherichia coli.Purified and refolded arresten protein could effectively inhibit proliferation of vascular endothelia cells.2 refs. 展开更多
关键词 Cloning and expression of human arresten gene and effect of its recombinant protein on endothelial cell proliferation
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从皮格马利翁效应到自我的镜视:人机交互中的情感投射与误认 被引量:2
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作者 徐强 《南京师大学报(社会科学版)》 北大核心 2025年第2期15-25,共11页
数字技术的发展催生了人机交互关系的形成,情感关系是人机交互关系的重要维度。数字复生和AI聊天伴侣从不同侧面满足了人们的情感需求,但又容易在自我的欲望投射下形成过度期待的皮格马利翁效应,带来自我镜视化的情感误认,从而落入情感... 数字技术的发展催生了人机交互关系的形成,情感关系是人机交互关系的重要维度。数字复生和AI聊天伴侣从不同侧面满足了人们的情感需求,但又容易在自我的欲望投射下形成过度期待的皮格马利翁效应,带来自我镜视化的情感误认,从而落入情感陷阱,造成情感依赖。人机交互关系是一种“它异关系”,而非“他者关系”,个体需要认清两者之间的边界,正视自己的情感,通过社会性建构,回归真实自我,才能建立起良性互动的人机交互关系。 展开更多
关键词 人机交互 皮格马利翁效应 自我镜视
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The Effect of Ethanol on the Transport of a Neutral Amino Acid in the Perfused Whole Human Placenta
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作者 Tai J. Kim Philip A. Rice 《Journal of Biomedical Science and Engineering》 2019年第2期121-150,共30页
The effect of ethanol on the transport of amino acids across the human placenta was studied in the dual perfusion apparatus using a non-metabolizable α-amino isobutyric acid (AIB). Results were obtained for thirty in... The effect of ethanol on the transport of amino acids across the human placenta was studied in the dual perfusion apparatus using a non-metabolizable α-amino isobutyric acid (AIB). Results were obtained for thirty intact whole human placentas in the absence (control group) and presence (ethanol group) of ethanol (500 - 1000 mg/dL). Experimental determinations of AIB transport at AIB concentrations of 5 - 100 mg/l, measured radioactively using (1&#8722;14 C-) AIB, were compared with a dual-active transport model. The diffusion coefficients of AIB were found to be (3.7 × 10&#8722;9 cm2/s) in the absence of ethanol and (2.3 × 10&#8722;9 cm2/s) in the presence of ethanol with no statistical difference (P = 0.25). The ratio of the fetal to maternal perfusate concentrations in the absence of ethanol (1.44) was statistically significant (P = 0.016) from the ratio in the presence of ethanol (1.20), which may indicate that active transport in the human placenta is inhibited by the presence of ethanol. The placental uptake from the maternal circulation was 2.6 (control) and 2.5 (ethanol) times greater than the uptake from the total circulation. The relative contribution of the diffusive transport to the net placental uptake of AIB from both the maternal and fetal circulations was less than that of active transport regardless of the presence of ethanol: control (38%) and ethanol (35%). It appears that the placental tissue plays the role of a mediator to maintain a fetal concentration higher than the maternal one by either enhancing the transfer from the maternal to the placental tissue or impairing the transfer in the opposite direction. 展开更多
关键词 effect ETHANOL TRANSPORT AMINO Acid human PLACENTA
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A Retrospective and Prospective Look at Human Rights Education in Chinese Universities and Colleges——A Simultaneous Discussion of the Basic Effects of Human Rights Education on the Human Rights Development Environment
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作者 LIU SHIPING 《The Journal of Human Rights》 2013年第6期5-8,共4页
1. The Role of Human Rights Education in Promoting Human Rights Development 1. Human rights education shapes the soft environment for human rights development
关键词 A Retrospective and Prospective Look at human Rights Education in Chinese Universities and Colleges A Simultaneous Discussion of the Basic effects of human Rights Education on the human Rights Development Environment
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Effect of Ambient Humidity on the Transmission of UV/Visible Light through Model Human Epidermis
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作者 Carlton Farley III Aschalew Kassu +1 位作者 Sandra Sadate Anup Sharma 《Open Journal of Applied Sciences》 2016年第3期153-157,共5页
Transmission of light through model human epidermal samples is investigated at four different wavelengths and at varying ambient humidity. Light from light emitting diodes (LEDs) is used for transmission measurements ... Transmission of light through model human epidermal samples is investigated at four different wavelengths and at varying ambient humidity. Light from light emitting diodes (LEDs) is used for transmission measurements through the samples at a UVA wavelength of 365 nm, and visible wavelengths of 460 nm, 500 nm, and 595 nm. Ambient air-humidity is varied between 20% and 100%. Results show that for high ambient humidity, near 100%, transmission of light through the epidermis is higher than at low ambient humidity, 60% or lower. These results are explained with a simple model of epidermis as a turbid medium and the effect of adsorbed water in reducing light-scattering by refractive-index-matching. Biological implications of increased light-transmission through epidermis at high ambient humidity are discussed. 展开更多
关键词 Model human Epidermis Model Skin effect of Humidity Transmission of Light Optical Properties of Epidermis
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2000—2019年黄淮海流域植被覆盖度变化归因研究 被引量:3
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作者 郑荣伟 张子元 +2 位作者 高学睿 王庆明 黄志强 《水土保持研究》 北大核心 2025年第3期214-221,共8页
[目的]科学评估黄淮海流域植被覆盖度变化中气候演变和人类活动的影响及定量贡献,为优化水土保持工作提供科学建议。[方法]基于黄淮海流域及其周围226个站点的气象数据以及SPOT-NDVI数据,利用像元二分法、线性斜率、Mann-Kendall趋势检... [目的]科学评估黄淮海流域植被覆盖度变化中气候演变和人类活动的影响及定量贡献,为优化水土保持工作提供科学建议。[方法]基于黄淮海流域及其周围226个站点的气象数据以及SPOT-NDVI数据,利用像元二分法、线性斜率、Mann-Kendall趋势检验和Person相关等方法,探讨植被覆盖度演变对蒸散发、降水、气温等气候因子响应的时间滞后效应,在残差分析法中增加时滞效应影响,评估了植被覆盖度变化原因。[结果](1)2000—2019年黄淮海流域年均植被覆盖度增长显著,线性斜率为0.038/10 a。(2)黄淮海流域植被覆盖度对降水响应滞后以0月和1月为主,分别占比52%和48%;对气温响应主要为无滞后性和滞后1月,分别占比61%和38%;对潜在蒸散发响应主要滞后1月和2月,分别占比49%和34%。[结论]影响黄淮海流域植被变化的主要因素为人类活动,气候变化的平均贡献率为33%,人类活动的平均贡献率为67%;其中约47%的区域人类活动影响贡献率超过80%,主要位于黄河流域西北部和东南部、海河流域南部和淮河流域。 展开更多
关键词 植被覆盖度 时滞效应 气候变化 人类活动 黄淮海流域
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