Scientific Reports
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2020
·Vol. 10
·期 1
·1-12
·
IF 3.998
Wu Yifan,Li Lingtong,Chen Shaopeng,Qin Jun,Chen Xiaolang,Zhou Dengfeng,Wu Hong
Poly( D -lactic acid) (PDLA) with different polyethylene glycol (PEG) segment synthesized PDLA-PEG-PDLA triblock copolymer through the ring-opening reaction of D -LA and PEG will be used as a toughening modifier. The microstructure, crystal structures and crystallization behaviors of this triblock copolymer were investigated by Fourier transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, X-ray diffraction (XRD), differential scanning calorimetry (DSC) and polarized optical microscopy (POM). The triblock copolymer is synthesized from the appearance of CH 2 stretching vibration peak at 2910 cm −1 and C-O stretching vibration peak at 1200 cm −1 from PEG in FTIR spectra. Moreover, the chemical shift that is about 3.6 ppm in 1 H NMR and 68.8ppm in 13 C NMR proves this matter. The results of XRD and DSC reveal that PDLA and PEG are crystallized separately, and are not fully compatible, and microphase separation has occurred in this triblock copolymer. PEG can induce the triblock copolymer to accelerate the rate of crystallization, allowing it to crystallize more completely in the same amount of time. When the molecular weight of PEG is 6000 or the ratio of D -LA/PEG is 1/1, the crystallizability of PDLA-PEG-PDLA triblock copolymer is the best.
研究领域:
材料科学
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高分子化学
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PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2017
·Vol. 134
·期 17
·
IF 1.86
Yanmei Guo,Jun Shao,Haoqing Hou
Linear poly( d -lactide) (PDLA) with various molecular weights is synthesized and incorporated into commercial poly( l -lactide) (PLLA) with different optical purities. And then, the crystallization, mechanical and thermal properties of the PLLA and PLLA/PDLA cast films are investigated. In the PLLA and PDLA/PLLA specimens with lower optical purity, few homochiral crystallites (HC) form in all the specimens and only a small amount of PLA stereocomplex crystallites (SC) are observed in the blends. The elongation at break of all the specimens is extraordinary high, >300%. Dynamic mechanical analyses indicate that the destruction temperature increases at first, and then depresses as enlarging the molecular weight of PDLA in these blends. For the PLLA and PLLA/PDLA with higher optical purity, more content of HC develops in neat PLLA, and both SC and HC produce in the PLLA/PDLA specimens. However, the strains of neat specimens and binary blends are much lower than that of specimens with lower optical purity. The specimens with higher optical purity exhibit higher destruction temperatures and lower loss factors. The high content of crystals (SC and HC) would act as the physical cross-linking points and provide a key factor to impede the deformation of neat PLLA and binary blends during stretching, which should result in the fragile behavior of the PLLA and PLLA/PDLA blends with higher optical purity. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134 , 44730.
研究领域:
材料科学
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高分子化学
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DOI
高影响因子
npj Biofilms and Microbiomes
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2023
·Vol. 9
·期 1
·1-14
·
IF 9.2
Hu Jie,Wu Yifan,Kang Luyuan,Liu Yisi,Ye Hao,Wang Ran,Zhao Jinbiao,Zhang Guolong,Li Xilong,Wang Junjun,Han Dandan
Elimination of specific enteropathogenic microorganisms is critical to gut health. However, the complexity of the gut community makes it challenging to target specific bacterial organisms. Accumulating evidence suggests that various foods can change the abundance of intestinal bacteria by modulating prophage induction. By using pathogenic Escherichia coli ( E. coli ) ATCC 25922 as a model in this research, we explored the potential of dietary modulation of prophage induction and subsequent bacterial survival. Among a panel of sugars tested in vitro, D -xylose was shown to efficiently induce prophages in E. coli ATCC 25922, which depends, in part, upon the production of D -lactic acid. In an enteric mouse model, prophage induction was found to be further enhanced in response to propionic acid. Dietary D -xylose increased the proportion of Clostridia which converted D -lactic acid to propionic acid. Intestinal propionic acid levels were diminished, following either oral gavage with the dehydrogenase gene ( ldhA )-deficient E. coli ATCC 25922 or depletion of intestinal Clostridia by administration of streptomycin. D -Xylose metabolism and exposure to propionic acid triggered E. coli ATCC 25922 SOS response that promoted prophage induction. E. coli ATCC 25922 mutant of RecA, a key component of SOS system, exhibited decreased phage production. These findings suggest the potential of using dietary components that can induce prophages as antimicrobial alternatives for disease control and prevention by targeted elimination of harmful gut bacteria.
研究领域:
微生物学
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胃肠病学
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营养学
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DOI
PubMed
高影响因子
Frontiers in Microbiology
·
2024
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IF 4
Yuhan Zheng,Feiyang Sun,Siyi Liu,Gang Wang,Huan Chen,Yongxin Guo,Xiufeng Wang,Maia Lia Escobar Bonora,Sitong Zhang,Yanli Li,Guang Chen
Background: The production of D-lactic acid (D-LA) from non-detoxified corn stover hydrolysate is hindered by substrate-mediated inhibition and low cell utilization times. In this study, we developed a novel temperature-sensitive hydrogel, F127-IEA, for efficient D-LA production using a cell-recycle batch fermentation process.Results: F127-IEA exhibited a porous structure with an average pore size of approximately 1 μm, facilitating the formation of stable Lactobacillus bulgaricus clusters within the gel matrix. It also maintains excellent mechanical properties. It also maintains excellent mechanical properties. F127-IEA immobilized Lactobacillus bulgaricus T15 (F127-IEA-T15) can be used in cell-recycle fermentation for over 150 days from glucose and 50 days from corn stover hydrolysate, achieving high production rates of D-LA from glucose (2.71 ± 0.85 g/L h) and corn stover hydrolysate (1.29 ± 0.39 g/L h). F127-IEA-T15 enhanced D-LA production by adsorbing and blocking toxic substances present in corn stover hydrolysate that are detrimental to cellular activity.Conclusions: The newly developed hydrogels in this study provide a robust platform for large-scale extraction of D-LA from non-detoxified corn stover.
研究领域:
微生物学
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生物工程
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发酵工程
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PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
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2022
·Vol. 41
·期 7
·1115-1122
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IF 3.815
Zhong Chan-Na,Liu Ya-Dong,Tang Juan,Chen Wei-Shuo,Li Shuang-Cheng,Shao Jun,Hou Hao-Qing
Blending of poly(levorotatory-lactic acid) (PLLA) and poly(dextrorotatory-lactic acid) (PDLA) produces the stereocomplex crystallites (PLA SC), which present higher melting temperature and mechanical properties than that of neat PLLA or PDLA. However, in the PLLA/PDLA blends with higher molecular weights, the phase separation occurs and the SC exhibits weak memory after melting, which lead to a small amount of SC together with a large amount of homochiral crystallites (HC) develop during crystallization from the melt. In this study, a small content of graphite oxide was blended with PLLA and PDLA to form ternary blends, and it was exciting to find that the formation of SC was enhanced gradually with the content of graphite oxide. The SC exclusively developed when 2 wt% graphite oxide was incorporated into the PLLA/PDLA, and the crystallinity with ∼50% was received even during fast cooling from the melt (−50 °C/min). The acceleration formation of SC was speculated due to the interaction between PLA molecular chains and the hydroxyl groups on the surface of graphite oxide and the obstruction of proliferation of graphite oxide.
研究领域:
高分子科学
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材料工程
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纳米复合材料
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结晶动力学
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DOI
高影响因子
JOURNAL OF DAIRY SCIENCE
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2025
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IF 4.4
Shuang Guan,Yuanmeng Wang,Ranran Zhang,Xinyu Yao,Shujing Lu,Xuming Deng,Jing Lu
Alcohol, one of the most widely popular and consumed beverages worldwide, often leads to acute alcoholic liver injury (AALI) when excessively consumed within a short timeframe. It can further induce alcoholic hepatitis, posing a serious risk to human health and public health safety. Pyroptosis, a typical mode of programmed cell death, is closely associated with the body's inflammatory response and plays a central role in AALI. However, the role of yogurt in acute alcohol-induced pyroptosis and inflammation is unclear. In this study, we found that yogurt and its metabolite d -lactate effectively mitigate alcohol-induced liver damage in mice, reducing hepatocyte pyroptosis and attenuating the inflammatory response. For the specific mechanism, further studies have shown that yogurt may inhibit autophagy through its substance d -lactate, leading to the accumulation of P62 protein in cells. This accumulation subsequently triggers the activation of Nrf2 through nonclassical pathways. Nrf2 translocates to the nucleus to play its antioxidant role, thereby reducing intracellular reactive oxygen species levels, inhibiting the activation of the alcohol-induced NLRP3 inflammasome, and ultimately alleviating pyroptosis and inflammation. Overall, this study reveals the potential protective effect of yogurt and its metabolite d -lactate in alleviating AALI, offering new insights and scientific basis for yogurt as a dietary strategy to improve AALI.
研究领域:
肝病学
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营养学
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分子生物学
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免疫学
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药理学
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细胞生物学
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产品关联
DOI
PubMed
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2020
·
IF 3.573
Congshu Feng,Yun Chen,Jun Shao,Haoqing Hou
Blending of poly(l-lactide) (PLLA) and poly(d-lactide) (PDLA) would produce polylactide stereocomplex crystallites (PLA SC). In the PLLA/PDLA specimens prepared by solution mixing or melt blending, the isomeric polymers were mixed in the molecular level. When the distance of these isomers increased, the crystallization behaviors of PLLA/PDLA were not clear yet. In this study, PLLA/PDLA blends were prepared by different electrospinning methods, i.e., spinning by mixed solution (DL-A), side-by-side mode (DL-B), and double spinnerets (DL-C). Results revealed that the distances between isomeric molecules increased in the order of DL-A, DL-B, and DL-C, and this distance influences the phase transition and subsequently crystallization behaviors. In the DL-A, the homochiral crystallites (HC) developed at first, and then SC formed in the specimen with lower content of PDLA. The formation of SC was observed at first, and less or no content of HC was developed with higher content of PDLA. For the DL-B group, the formation of HC was observed at ∼100 °C, and the SC were produced around 140 °C irrespective of composition. More content of SC was produced during or after melting of HC. When referring to the DL-C group, the HC developed at the first stage, and the SC were produced during or after melting of PLA HC. In addition, the SC that developed in the three groups have different nucleation efficiencies for the subsequent formation of HC. The nucleation efficiency increased in the order of DL-A < DL-B < DL-C, and these results hinted that not only the content but also the distribution of SC affects the formation of HC.
研究领域:
材料科学
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高分子科学
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纳米技术
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DOI
高影响因子
JOURNAL OF FOOD COMPOSITION AND ANALYSIS
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2025
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IF 4.6
Yangzhou Xie,Sitao Wang,Yu Tian,Kexi Ye,Zhigang Xu,Han Zheng,Wei Jiang,Fengmei Zhang,Xiaoxi Si
Excessive D-lactic acid in fermented foods can result in unpleasant flavors and is difficult for the human body to metabolize. This study is the first to combine tandem column technology (C18 and Poroshell chiral-T) with a machine learning strategy. The method achieved a resolution of 2.86, with a concentration range of 50.00 μg·L −1 -50.00 mg·L −1 and a limit of detection of 16.67 μg·L −1 . We aimed to classify different lactic acid products and tobacco, and the research showed that L-lactic acid was predominant in all food analyses , while D-lactic acid was only found in lactic acid products In addition, the machine learning algorithms were optimized, and the random forest model effectively distinguished samples with similar lactic acid content. Based on this collaborative model of tandem column and machine learning, lactic acid chiral biomarkers gained the ability to classify food samples. The accuracy of model reached 80 %. This strategy contributes to the chiral analysis of lactic acid in complex food matrices. It also demonstrates the practical value of classification in food research.
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高影响因子
Nutrients
·
2024
·Vol. 16
·期 9
·1395
·
IF 4.8
Xinru Du,Yongheng Yan,Yufeng Dai,Ruijie Xu
Numerous studies have investigated the immunomodulatory effects of yogurt, but the underlying mechanism remained elusive. This study aimed to elucidate the alleviating properties of yogurt on immunosuppression and proposed the underlying mechanism was related to the metabolite D-lactate. In the healthy mice, we validated the safety of daily yogurt consumption (600 μL) or D-lactate (300 mg/kg). In immunosuppressed mice induced by cyclophosphamide (CTX), we evaluated the immune regulation of yogurt and D-lactate. The result showed that yogurt restored body weight, boosted immune organ index, repaired splenic tissue, recovered the severity of delayed-type hypersensitivity reactions and increased serum cytokines (IgA, IgG, IL-6, IFN-γ). Additionally, yogurt enhanced intestinal immune function by restoring the intestinal barrier and upregulating the abundance of Bifidobacterium and Lactobacillus. Further studies showed that D-lactate alleviated immunosuppression in mice mainly by promoting cellular immunity. D-lactate recovered body weight and organ development, elevated serum cytokines (IgA, IgG, IL-6, IFN-γ), enhanced splenic lymphocyte proliferation and increased the mRNA level of T-bet in splenic lymphocyte to bolster Th1 differentiation. Finally, CTX is a chemotherapeutic drug, thus, the application of yogurt and D-lactate in the tumor-bearing mouse model was initially explored. The results showed that both yogurt (600 μL) and D-lactate (300 mg/kg) reduced cyclophosphamide-induced immunosuppression without promoting tumor growth. Overall, this study evaluated the safety, immune efficacy and applicability of yogurt and D-lactate in regulating immunosuppression. It emphasized the potential of yogurt as a functional food for immune regulation, with D-lactate playing a crucial role in its immunomodulatory effects.
研究领域:
免疫学
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营养学
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药理学
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微生物学
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产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF POLYMER SCIENCE
·
2019
·Vol. 38
·期 3
·298-310
·
IF 2.804
Feng Cong-Shu,Chen Yun,Shao Jun,Li Gao,Hou Hao-Qing
In this study, the poly(D-lactide)-block-poly(butylene succinate)-block-poly(D-lactide) (PDLA- b -PBS- b -PDLA) triblock copolymers with a fixed length of PBS and various lengths of PDLA are synthesized, and the crystallization behaviors of the PDLA and PBS blocks are investigated. Although both the crystallization behaviors of PBS and PDLA blocks depend on composition, they exhibit different variations. For the PDLA block, its crystallization behaviors are mainly influenced by temperature and block length. The crystallization signals of PDLA block appear in the B-D 2–2 specimen, and these signals get enhanced with PDLA block length. The crystallization rates tend to decrease with increasing PDLA block lendth during crystallizing at 90 and 100 °C. Crystallizing at higher temperature, the crystallization rates increase at first and then decrease with block length. The crystallization rates decrease as elevating the crystallization temperature. The melting temperatures of PDLA blocks increase with block lengths and crystallization temperatures. For the PBS block, its crystallization behaviors are mainly controlled by the nucleation and confinement from PDLA block. The crystallization and melting enthalpies as well as the crystallization and melting temperatures of PBS block reduce as a longer PDLA block has been copolymerized, while the crystallization rates of the PBS block exhibit unique component dependence, and the highest rate is observed in the B-D 2–2 specimen. The Avrami exponent of PBS crystallites is reduced as a longer PDLA block is incorporated or the sample is crystallized at higher temperature. This investigation provides a convenient route to tune the crystallization behavior of PBS and PLA.
研究领域:
高分子化学
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材料科学
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DOI
高影响因子
CARBOHYDRATE POLYMERS
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2025
·
IF 12.5
Huiqing Wang,Xiaoyue Zhou,Ke Wu,Longxiang Tang,Xiaorui Duan,Wei Li
The inefficiency and instability of free enzymes in the chiral separation of high-purity D-pantolactone, a crucial intermediate in vitamin B5 synthesis, pose significant challenges, with nanostructured materials offering promising solutions. In this study, D-Lactonohydrolase (D-lacs) was immobilized in crab-derived chitin nanofibrous microspheres (ChNFM), achieving high enzyme loading and excellent reusability. By combining physical absorption and chemical cross-linking, stable immobilization of D-lacs was realized. The enzyme loading capacity of D-Lacs on ChNFM was gradually increased as the particle size of ChNFM decreased. Batch hydrolysis using D-Lacs@ChNFM was conducted for 50 consecutive times, maintaining an average degree of hydrolysis of 30.0%, with stable enzyme activity throughout. Compared to the commercial immobilized D-lacs carrier, D-Lacs@ChNFM exhibited superior hydrolytic efficiency, higher batch stability, and excellent biodegradability. This work highlights the potential of ChNFM as an efficient and eco-friendly carrier for enzyme immobilization, offering a promising platform for scalable DL-pantolactone separation and greener vitamin B5 production.
研究领域:
生物催化
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纳米材料
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绿色化学
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酶工程
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制药工程
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手性合成
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可持续材料
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF PHARMACEUTICAL AND BIOMEDICAL ANALYSIS
·
2023
·
IF 3.4
Yang Chang,Yafei Xia,Xiaojun Liu,Putian Yu,Furong Fan,Yangyang Shi,Shixin Yan,Shu Yan
Background Cholestasis is a commonly occurring disorder induced by impaired bile flow, for which there is no effective treatment so far. Qingre Lidan decoction (QRLD) is a clinically used herbal compound for the long-term treatment of bile circulation disorders arising from inflammation and obstruction in the gallbladder and bile ducts. The objective of this study was to investigate the protective effect of QRLD on cholestatic liver injury and its possible mechanism. Methods α-Naphthyl isothiocyanate (ANIT) was used to induce cholestatic liver injury in rats. Liver histopathology and serum biochemical markers were used to assess QRLD's protective impact. The possible biomarkers and mechanism of the therapeutic benefits of QRLD were investigated using a UHPLC-based Q-Exactive Orbitrap MS / MS untargeted serum metabolomics technique together with 16 S rRNA microbiota profiling. Afterwards, using RT-qPCR as well as Western Blot techniques, the expression of pertinent indicators was determined. Results The intervention effect of QRLD was stronger at medium and high dosages than at low doses, and it dramatically decreased the levels of serum biochemical markers in cholestatic rats reflecting alterations in liver function and relieving ANIT-induced abnormalities in the liver's histopathology. Serum metabolomics showed that QRLD could affect the metabolic profile of cholestatic rats, mainly related to glycerophospholipid metabolism, taurine and hypotaurine metabolism, alanine, aspartate and glutamate metabolism, and histidine metabolic pathway. Additionally, analysis of 16 S rRNA gene sequencing indicated that QRLD could moderate ANIT-induced microbiota disorders, particularly Romboutsia, Bifidobacterium, Fusicatenibacter, Prevotella_9, Prevotellaceae_NK3B31_group and Prevotella_1. Other experimental results showed that QRLD significantly upregulated the mRNA and protein expression of PPARα, CYP7A1 and NTCP in the liver, inhibited the expression of p-IκBα, p-p65 and TNFα while increasing the anti-inflammatory factor IL-10, and downregulated the expression of MDA (a peroxidation product) and D -lactic acid (an intestinal barrier indicator) while increasing the expression of SOD and GSH. Conclusions QRLD can effectively regulate endogenous metabolites and microbiota disorders in cholestatic rats that are correlated with the attenuation of inflammation and oxidative stress.
研究领域:
药理学
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肝病学
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代谢组学
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微生物学
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分子生物学
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产品关联
DOI
PubMed
高影响因子