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神经胶质细胞与神经突触的相互作用——从星形胶质细胞到小胶质细胞和少突胶质细胞谱系细胞 被引量:1
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作者 Yao Liu xi shen +6 位作者 Yuhan Zhang xiaoli Zheng Carlos Cepeda YaoWang Shumin Duan xiaoping Tong 杜一星(编译) 《神经损伤与功能重建》 2023年第9期F0003-F0003,共1页
哺乳动物的大脑是一个由神经元、神经胶质细胞和超过1×1014个突触组成的复杂的器官。神经元是一组异质的电活性细胞,形成大脑复杂电回路的框架。然而,神经胶质细胞约占哺乳动物中枢神经系统(CNS)所有神经细胞的一半,主要分为星形... 哺乳动物的大脑是一个由神经元、神经胶质细胞和超过1×1014个突触组成的复杂的器官。神经元是一组异质的电活性细胞,形成大脑复杂电回路的框架。然而,神经胶质细胞约占哺乳动物中枢神经系统(CNS)所有神经细胞的一半,主要分为星形胶质细胞、小胶质细胞、少突胶质细胞(OL)和少突胶质细胞前体细胞(OPC);神经胶质细胞主要为大脑中的神经元提供营养支持。近二十年来,“三联突触”的概念引起了广泛关注,该概念强调星形胶质细胞是突触的组成部分,并在接受神经元信号后以反馈方式调节神经元活动。自此,神经胶质细胞的突触调节得到了广泛的研究和实质性的修改。本综述总结了关于神经胶质细胞(特别是小胶质细胞和OL谱系细胞)如何影响和重塑大脑突触结构和功能的最新重要发现。我们的综述强调了神经元-神经胶质细胞串扰的细胞和分子方面,并提供了有关神经元和神经胶质细胞之间的异常突触通讯如何导致神经病理学的额外信息。 展开更多
关键词 星形胶质细胞 小胶质细胞 少突胶质细胞前体细胞 少突胶质细胞 突触传递
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Acute abdomen caused by spontaneous rupture of degenerative hysteromyoma during pregnancy:A case report
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作者 Ying Xu xi shen +1 位作者 xiao-Yu Pan Shan Gao 《World Journal of Clinical Cases》 SCIE 2023年第15期3631-3636,共6页
BACKGROUND Hysteromyoma is not a rare tumor among pregnant women.During pregnancy,the symptoms caused by hysteromyoma can be improved through conservative treatment in most cases.However,in order to ensure the safety ... BACKGROUND Hysteromyoma is not a rare tumor among pregnant women.During pregnancy,the symptoms caused by hysteromyoma can be improved through conservative treatment in most cases.However,in order to ensure the safety of mothers and children,surgeries are necessary in some special cases.CASE SUMMARY We report a case of pregnancy complicated with hysteromyoma red degeneration.The patient had peritonitis after sudden abdominal pain during the 20th week of pregnancy.Laparoscopic exploration suggested rupture and bleeding of hysteromyoma,which were improved after drainage and an anti-inflammatory treatment.A cesarean section was performed after full term.This case shows the complications of rupture after red degeneration of hysteromyoma during pregnancy.CONCLUSION We should be alert to rupture of hysteromyoma during pregnancy,and active laparoscopic exploration is essential to improve the prognosis of such patients. 展开更多
关键词 Leiomyoma degeneration Myoma rupture Acute abdomen PREGNANCY Hysteromyoma bleeding Case report
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Ahmed valve implantation for neovascular glaucoma after 23-gauge vitrectomy in eyes with proliferative diabetic retinopathy 被引量:6
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作者 Yu Cheng xiao-Hong Liu +1 位作者 xi shen Yi-sheng Zhong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2013年第3期316-320,共5页
·AIM: To report on the outcome of Ahmed glaucoma valve (AGV) implantation for the management of neovascular glaucoma (NVG) after 23 -gauge vitrectomy for proliferative diabetic retinopathy (PDR). ·METHODS: T... ·AIM: To report on the outcome of Ahmed glaucoma valve (AGV) implantation for the management of neovascular glaucoma (NVG) after 23 -gauge vitrectomy for proliferative diabetic retinopathy (PDR). ·METHODS: Twelve medically uncontrolled NVG with earlier 23 -gauge vitrectomy for PDR underwent AGV implantation. The control of intraocular pressure (IOP), preoperative and postoperative best -corrected visual acuity, the development of intraoperative and postoperative complications were evaluated during the follow-up. ·RESULTS: The mean follow-up was 15.4±4.3 months (9-23 months). Mean preoperative IOP was 49.4±5.1mmHg and mean postoperative IOP at the last visit was 17.5 ± 1.6mmHg. The control of IOP was achieved at the final follow -up visits in all patients, however, 8 of 12 patients still needed anti-glaucoma medication (mean number of medications, 0.8±0.7). The visual acuity improved in nine eyes, and the visual acuity unchanged in three eyes at the final follow -up visits. The complications that occurred were minor hyphema in three eyes, choroid detachment in two eyes, and the minor hyphema and choroid detachments were reabsorbed without any surgical intervention. ·CONCLUSION: AGV implantation is a safe and effective procedure that enables successful IOP control and vision preservation in the NVG patients with the history of earlier 23-gauge vitrectomy for PDR.· 展开更多
关键词 Ahmed glaucoma valve implantation neovascular glaucoma proliferative diabetic retinopathy 23-gauge vitrectomy
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Anisotropic,Wrinkled,and Crack-Bridging Structure for Ultrasensitive,Highly Selective Multidirectional Strain Sensors 被引量:4
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作者 Heng Zhang Dan Liu +6 位作者 Jeng-Hun Lee Haomin Chen Eunyoung Kim xi shen Qingbin Zheng Jinglei Yang Jang-Kyo Kim 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第8期121-135,共15页
Flexible multidirectional strain sensors are crucial to accurately determining the complex strain states involved in emerging sensing applications.Although considerable efforts have been made to construct anisotropic ... Flexible multidirectional strain sensors are crucial to accurately determining the complex strain states involved in emerging sensing applications.Although considerable efforts have been made to construct anisotropic structures for improved selective sensing capabilities,existing anisotropic sensors suffer from a trade-off between high sensitivity and high stretchability with acceptable linearity.Here,an ultrasensitive,highly selective multidirectional sensor is developed by rational design of functionally different anisotropic layers.The bilayer sensor consists of an aligned carbon nanotube(CNT)array assembled on top of a periodically wrinkled and cracked CNT-graphene oxide film.The transversely aligned CNT layer bridge the underlying longitudinal microcracks to effectively discourage their propagation even when highly stretched,leading to superior sensitivity with a gauge factor of 287.6 across a broad linear working range of up to 100%strain.The wrinkles generated through a pre-straining/releasing routine in the direction transverse to CNT alignment is responsible for exceptional selectivity of 6.3,to the benefit of accurate detection of loading directions by the multidirectional sensor.This work proposes a unique approach to leveraging the inherent merits of two cross-influential anisotropic structures to resolve the trade-off among sensitivity,selectivity,and stretchability,demonstrating promising applications in full-range,multi-axis human motion detection for wearable electronics and smart robotics. 展开更多
关键词 Anisotropic strain sensor WRINKLE Aligned carbon nanotube Stretchability Complex motion detection
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Decadal Variation of the Impact of La Nina on the Winter Arctic Stratosphere 被引量:3
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作者 Shuangyan YANG Tim LI +1 位作者 Jinggao HU xi shen 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第5期679-684,共6页
The impact of La Ni?a on the winter Arctic stratosphere has thus far been an ambiguous topic of research. Contradictory results have been reported depending on the La Ni?a events considered. This study shows that this... The impact of La Ni?a on the winter Arctic stratosphere has thus far been an ambiguous topic of research. Contradictory results have been reported depending on the La Ni?a events considered. This study shows that this is mainly due to the decadal variation of La Ni?a’s impact on the winter Arctic stratosphere since the late 1970 s. Specifically,during the period1951–78,the tropospheric La Ni?a teleconnection exhibits a typical negative Pacific–North America pattern,which strongly inhibits the propagation of the planetary waves from the extratropical troposphere to the stratosphere,and leads to a significantly strengthened stratospheric polar vortex. In contrast,during 1979–2015,the La Ni?a teleconnection shifts eastwards,with an anomalous high concentrated in the northeastern Pacific. The destructive interference of the La Ni?a teleconnection with climatological stationary waves seen in the earlier period reduces greatly,which prevents the drastic reduction of planetary wave activities in the extratropical stratosphere. Correspondingly,the stratospheric response shows a less disturbed stratospheric polar vortex in winter. 展开更多
关键词 La Ni?a stratospheric polar vortex decadal variation planetary waves
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Evaluation of retinal and choroidal changes in patients with Alzheimer’s type dementia using optical coherence tomography angiography 被引量:3
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作者 Ze-Bing Li Zhong-Jing Lin +3 位作者 Na Li Huan Yu Yan-Lin Wu xi shen 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2021年第6期860-868,共9页
AIM:To evaluate the changes in fundus parameters in patients with Alzheimer’s type dementia(ATD)using optical coherence tomography angiography(OCTA),to record flash electroretinograms(ERG)using the RETeval system and... AIM:To evaluate the changes in fundus parameters in patients with Alzheimer’s type dementia(ATD)using optical coherence tomography angiography(OCTA),to record flash electroretinograms(ERG)using the RETeval system and to explore changes in retinal function.METHODS:Twenty-nine patients with ATD and 26 age-matched normal subjects were enrolled.All subjects underwent OCTA scans to analyse the superficial retinal vessel parameters in the macular area,including the vessel length density,the vessel perfusion density and the area of foveal avascular zone(FAZ),as well as the choroidal thickness.The differences between the patients with ATD and the normal control group were compared and explored the relevant factors affecting vessel parameters.We also recorded the flash ERGs using the RETeval system and intended to explore changes in retinal function by analysing the ERG image amplitude in patients with ATD.RESULTS:The vessel parameters[Pvessel length density=0.005 and Pvessel perfusion density=0.006]and average choroid thickness(P<0.001)in the macular area of the ATD group was less than the control group.The FAZ area was statistically significantly enlarged in the ATD group(P<0.001).These parameters were correlated with the Mini-Mental State Examination(MMSE)score and the Montreal Cognitive Assessment(MoCA).CONCLUSION:Patients with ATD exhibit decreases in the parameters associated with fundus.In addition,these indicators significantly correlate with the MMSE score and the MoCA score.OCTA may be an adjunct tool with strong potential to track changes in the diagnosis and monitoring the progression of the disease. 展开更多
关键词 optical coherence tomography angiography Alzheimer’s type dementia Mini-Mental State Examination Montreal Cognitive Assessment scale RETeval system flash electroretinogram
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Macrostructure and properties of thin walled copper tubes prepared by the downward continuous unidirectional solidification method 被引量:2
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作者 xi shen Hong Zhang +3 位作者 Zi-dong Wang Hua-fen Lou Yi-ming Jia Ping-xia Hu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第1期63-68,共6页
The macrostructure and properties of the thin walled copper tube prepared by the downward continuous unidirectional solidification (DCUS) method were studied. The result shows that the macrostructure is closely rela... The macrostructure and properties of the thin walled copper tube prepared by the downward continuous unidirectional solidification (DCUS) method were studied. The result shows that the macrostructure is closely related to the solid-liquid interface profile, which is influenced by the distance between the cooling water location and the solidification front. The mechanical properties of the thin walled copper tube prepared by the DCUS method are near those of the normal cast copper, and it has good relative density, electrical conductivity, and elongation, which are not greatly affected by casting speed. The thin walled copper tube prepared by the DCUS method also has good processing properties that can be taken to further drawing procedures directly without an intermediate process, and obtains good mechanical properties with the total processing rate of 89.8%. 展开更多
关键词 unidirectional solidification copper tube short process MACROSTRUCTURE mechanical properties
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Clinical efficacy of Ahmed glaucoma valve implantation combined with 23-gauge vitrectomy for medically uncontrolled neovascular glaucoma with proliferative diabetic retinopathy 被引量:2
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作者 Zhong-Jing Lin Zheng-Hua Chen +3 位作者 Shou-Yue Huang Jun Sun xi shen Yi-sheng Zhong 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2020年第5期832-836,共5页
AIM:To describe the clinical results of combined Ahmed valve implantation and 23-gauge vitrectomy for medically uncontrolled neovascular glaucoma(NVG)secondary to proliferative diabetic retinopathy(PDR).METHODS:The me... AIM:To describe the clinical results of combined Ahmed valve implantation and 23-gauge vitrectomy for medically uncontrolled neovascular glaucoma(NVG)secondary to proliferative diabetic retinopathy(PDR).METHODS:The medical records of medically uncontrolled NVG patients with PDR who underwent Ahmed valve implantation and 23-gauge vitrectomy between March 2016 and December 2018 were reviewed.Enrolled patients had at least 6-month follow-up.Panretinal photocoagulation(PRP),anti-vascular endothelial growth factor,surgery and medication history were documented.RESULTS:Eleven eyes of 11 patients were included in our study.The visual acuity improved in 8 eyes and remained unchanged in 3 eyes.The preoperative intraocular pressure(IOP)was significantly decreased at the last follow-up(48.8±4.3 to 17.0±1.5 mm Hg,P<0.001).All eyes needed three topical anti-glaucomatous medications before surgery,but the number was significantly reduced to 0.72±0.19 at the last visit(P<0.001).Four eyes had choroidal detachment and 3 eyes had minor hyphemia,all of which gradually resolved without treatments in one week.CONCLUSION:Ahmed glaucoma valve implantation combined with 23-gauge vitrectomy might be a safe and alternative treatment for NVG with PDR. 展开更多
关键词 Ahmed glaucoma valve VITRECTOMY neovascular glaucoma diabetic retinopathy
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Erythropoietin upregulates growth associated protein-43 expression and promotes retinal ganglion cell axonal regeneration in vivo after optic nerve crush
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作者 Haibo Tan xin Kang +4 位作者 Yisheng Zhong xi shen Yu Cheng Qin Jiao Lianfu Deng 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第4期295-301,共7页
In this study, we established a rat model of optic nerve crush to explore the effects of erythropoietin on retinal ganglion cell axonal regeneration. At 15 days after injury in erythropoietin treated rats, retinal gan... In this study, we established a rat model of optic nerve crush to explore the effects of erythropoietin on retinal ganglion cell axonal regeneration. At 15 days after injury in erythropoietin treated rats, retinal ganglion cell densities in regions corresponding to the 1/6, 3/6 and 5/6 ratios of the retinal radius were significantly increased. In addition, the number of growth associated protein-43 positive axons was significantly increased at different distances (50, 250 and 500 pm) from the crush site after erythropoietin treatment. Erythropoietin significantly increased growth associated protein-43 protein levels in the retina after crush injury, as determined by westem blot and immunofluorescence analysis. These results demonstrate that erythropoietin protects injured retinal ganglion cells and promotes axonal regeneration. 展开更多
关键词 ERYTHROPOIETIN retinal ganglion cells axonal regeneration optic nerve crush neural regeneration
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Superinsulating BNNS/PVA Composite Aerogels with High Solar Reflectance for Energy-Efficient Buildings
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作者 Jie Yang Kit‑Ying Chan +5 位作者 Harun Venkatesan Eunyoung Kim Miracle Hope Adegun Jeng‑Hun Lee xi shen Jang‐Kyo Kim 《Nano-Micro Letters》 SCIE EI CAS CSCD 2022年第3期292-307,共16页
With the mandate of worldwide carbon neutralization,pursuing comfortable living environment while consuming less energy is an enticing and unavoidable choice.Novel composite aerogels with super thermal insulation and ... With the mandate of worldwide carbon neutralization,pursuing comfortable living environment while consuming less energy is an enticing and unavoidable choice.Novel composite aerogels with super thermal insulation and high sunlight reflection are developed for energy-efficient buildings.A solvent-assisted freeze-casting strategy is used to produce boron nitride nanosheet/polyvinyl alcohol(BNNS/PVA)composite aerogels with a tailored alignment channel structure.The effects of acetone and BNNS fillers on microstructures and multifunctional properties of aerogels are investigated.The acetone in the PVA suspension enlarges the cell walls to suppress the shrinkage,giving rise to a lower density and a higher porosity,accompanied with much diminished heat conduction throughout the whole product.The addition of BNNS fillers creates whiskers in place of disconnected transverse ligaments between adjacent cell walls,further ameliorating the thermal insulation transverse to the cell wall direction.The resultant BNNS/PVA aerogel delivers an ultralow thermal conductivity of 23.5 mW m^(−1) K^(−1) in the transverse direction.The superinsulating aerogel presents both an infrared stealthy capability and a high solar reflectance of 93.8%over the whole sunlight wave-length,far outperforming commercial expanded polystyrene foams with reflective coatings.The anisotropic BNNS/PVA composite aerogel presents great potential for application in energy-saving buildings. 展开更多
关键词 Boron nitride nanosheets Solvent-assisted freeze-casting Thermally insulating aerogel Solar reflectance Energy-saving buildings
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Synthesis and Characterization of Novel Dimethylgallium Complexes
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作者 Wu BI Jin Qi ZHANG +2 位作者 Jing Zhi TIAN xi shen Hui xian ZOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第11期965-966,共2页
Two novel dimethylgallium complexes were synthesized and their structures were elucidated by elemental analysis, H-1 NMR, IR and MS spectra.
关键词 novel dimethylgallium complexes SYNTHESIS CHARACTERIZATION
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Magnetic Anisotropy Induced by Orbital Occupation States in La_(0.67)Sr_(0.33)MnO_(3) Films
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作者 王怀翔 宋京华 +6 位作者 王伟鹏 陈沅沙 沈希 姚湲 李俊杰 孙继荣 禹日成 《Chinese Physics Letters》 SCIE CAS CSCD 2021年第8期115-120,共6页
Interface engineering is an effective and feasible method to regulate the magnetic anisotropy of films by altering interfacial states between films.Using the technique of pulsed laser deposition,we prepared La_(0.67)S... Interface engineering is an effective and feasible method to regulate the magnetic anisotropy of films by altering interfacial states between films.Using the technique of pulsed laser deposition,we prepared La_(0.67)Sr_(0.33)MnO_(3)(LSMO)and La_(0.67)Sr_(0.33)MnO_(3)/SrCoO_(2.5)(LSMO/SCO)films on(110)-oriented La_(0.3)Sr_(0.7)Al_(0.65)Ta_(0.35)O_(3) substrates.By covering the SCO film above the LSMO film,we transformed the easy magnetization axis of LSMO from the[001]axis to the[110]axis in the film plane.Based on statistical analyses,we find that the corresponding Mn-Mn ionic distances are different in the two types of LSMO films,causing different distortions of Mn-O octahedron in LSMO.In addition,it also induces diverse electronic occupation states in Mn^(3+)ions.The e_(g) electron of Mn^(3+)occupies 3z^(2)-r^(2) and x^(2)-y^(2) orbitals in the LSMO and LSMO/SCO,respectively.We conclude that the electronic spin reorientation leads to the transformation of the easy magnetization axis in the LSMO films. 展开更多
关键词 film MAGNETIZATION OCCUPATION
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Analysis of Dynamic Changes in Habitat Quality Based on InVEST Models:A Case Study of Pu er City,Yunnan Province
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作者 Qinfang ZHOU Yang YE +1 位作者 Pin MA xi shen 《Meteorological and Environmental Research》 CAS 2021年第1期79-86,共8页
Based on the data of land use status in 2009-2018 in the annual change survey results of Pu er City,Yunnan Province,China,the habitat quality in the city were studied by using InVEST models.The results show that the a... Based on the data of land use status in 2009-2018 in the annual change survey results of Pu er City,Yunnan Province,China,the habitat quality in the city were studied by using InVEST models.The results show that the area of cultivated land,construction land,and unused land in Pu er City continuously increased from 2009 to 2018.The growth rate of cultivated land and construction land in the next three years was significantly higher than that in the previous three years,while the area of gardens,grassland and woodland continuously decreased.From 2009 to 2018,the habitat quality in Pu er City showed a downward trend,that is,there was a clear increase in the proportion of moderate and poor habitat quality and a decrease in the proportion of superior and good habitat quality.Changes in habitat quality calculated by InVEST models can be used as a grasp of regional ecological environment in the investigation before the audit of natural resource assets and breakthroughs in finding clues of problems,thereby improving the scientificity and efficiency of audit work of natural resource assets. 展开更多
关键词 Habitat quality InVEST model Audit of natural resources assets GIS
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Effects of Xinfeng capsule on pulmonary function based on treg-mediated notch pathway in a rat model of adjuvant arthritis 被引量:17
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作者 Lei Wan Jian Liu +10 位作者 Chuanbing Huang Yuan Wang xi shen Wandong Zhang Guizheng Wang Haixia Fan Yao Ge Ruilian Chen Yunxiang Cao Ruikai Zong Li Lei 《Journal of Traditional Chinese Medicine》 SCIE CAS CSCD 2012年第3期430-436,共7页
OBJECTIVE:To observe the impact of xinfeng xapsule(XFC) on pulmonary function in a rat model of adjuvant arthritis(AA) and to investigate the mechanism of action.METHODS:Forty rats were randomly divided into four grou... OBJECTIVE:To observe the impact of xinfeng xapsule(XFC) on pulmonary function in a rat model of adjuvant arthritis(AA) and to investigate the mechanism of action.METHODS:Forty rats were randomly divided into four groups of ten:normal control(NC);model control(MC);tripterygium glycosides tablet(TPT);and xinfeng capsule(XFC).Except for the NC group,AA was induced in all rats by intracutaneous injection of 0.1 mL Freund's complete adjuvant in the right paw on the 19th day.NC and MC groups were given(0.9%) physiological saline.The TPT and XFC groups were given TPT(10 mg/kg) and XFC(1.2 g/kg),respectively.Thirty days after administration,changes in paw edema(E),the arthritis index(AI),pulmonary function,levels of regulatory T-cells(Treg),ultrastructure of lung tissue,and expression of Notch receptors and ligands in lung tissue were observed.RESULTS:In the MC group,E and the AI were increased and pulmonary function significantly decreased;the structure of alveolar type-II cells was damaged;ratios of Treg in peripheral blood were reduced;and expression of Notch receptors such as Notch3 and Notch4 and ligands such as Delta1 in lung tissue were significantly increased whereas expression of Notch1,Jagged1 and Jagged2 were significantly decreased.After intervention with XFC,E and the AI were decreased;pulmonary function was enhanced;the structure of alveolar type-II cells was improved;and expression of Treg,Notch1,Jagged1,Jagged2 was elevated,whereas that of Notch3,Notch4 and Delta1 was reduced.CONCLUSION:XFC can not only inhibit E and the AI and improve joint symptoms,it can also improve pulmonary function and reduce inflammation in lung tissue.These actions could be carried out through increases in the expression of Treg,Notch receptors(Notch1) and ligands(Jagged1,Jagged2),and reductions in the expression of Notch3,Notch4 and Delta1.These phenomena would reduce the deposition of immune complexes and the inflammatory response in lung tissue,thereby improving joint symptoms and pulmonary function. 展开更多
关键词 佐剂性关节炎 调节性T细胞 NOTCH 大鼠模型 肺功能 信号通路 胶囊 新风
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Graphene and MXene-based porous structures for multifunctional electromagnetic interference shielding 被引量:5
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作者 xi shen Jang-Kyo Kim 《Nano Research》 SCIE EI CSCD 2023年第1期1387-1413,共27页
Electrically conductive porous structures are ideal candidates for lightweight and absorption-dominant electromagnetic interference(EMI)shielding.In this review,we summarize the recent progress in developing porous co... Electrically conductive porous structures are ideal candidates for lightweight and absorption-dominant electromagnetic interference(EMI)shielding.In this review,we summarize the recent progress in developing porous composites and structures from emerging two-dimensional(2D)graphene and MXene nanosheets for EMI shielding applications.Important properties contributing to various energy loss mechanisms are probed with a critical discussion on their correlations with EMI shielding performance.Technological approaches to constructing bulk porous structures,such as 2D porous films,three-dimensional(3D)aerogels and foams,and hydrogels,are compared to highlight important material and processing parameters required to achieve optimal microstructures.A comprehensive comparison of EMI shielding performance is also carried out to elucidate the effects of different assembly techniques and microstructures.Distinctive multifunctional applications in adaptive EMI shielding,mechanical force attenuation,thermal management,and wearable devices are introduced,underlining the importance of unique compositions and microstructures of porous composites.The process–structure–property relationships established in this review would offer valuable guidance and insights into the design of lightweight EMI shielding materials. 展开更多
关键词 porous composite GRAPHENE MXene electrical conductivity electromagnetic interference(EMI)shielding
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高稳定性铋基钙钛矿纳米晶的可控合成:结构和光物理性质
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作者 耿慧芳 黄转转 +16 位作者 耿华修 刘思宇 Maria A Naumova Raffaele Salvia 陈司淇 韦钧励 张丽芙 邹贤劭 林伟华 蔡欣怡 袁明鉴 胡振芃 沈希 于日成 郑凯波 Sophie E.Canton 付学文 《Science China Materials》 SCIE EI CAS CSCD 2023年第5期2079-2089,共11页
铋基钙钛矿因毒性低成为铅基钙钛矿的潜在替代品.目前,对铋基钙钛矿纳米晶的化学组成、晶体结构以及光物理过程的研究还缺乏系统性.特别地,紫外-可见吸收光谱和激发态载流子动力学,在已发表的论文中存在相当大的争议.在本文中,我们通过... 铋基钙钛矿因毒性低成为铅基钙钛矿的潜在替代品.目前,对铋基钙钛矿纳米晶的化学组成、晶体结构以及光物理过程的研究还缺乏系统性.特别地,紫外-可见吸收光谱和激发态载流子动力学,在已发表的论文中存在相当大的争议.在本文中,我们通过热注入法成功地合成了纯相的Cs_(3)BiBr_(6)和Cs_(3)Bi_(2)Br_(9)纳米晶,并通过调节热注入的温度来精确控制二者的化学组成和结构.在此基础上,系统研究了不同形貌和不同尺寸的Cs_(3)Bi_(2)Br_(9)纳米晶的紫外-可见吸收光谱,澄清了在这方面存在的争议.采用飞秒瞬态吸收光谱系统研究了Cs_(3)Bi_(2)Br_(9)纳米晶的激发态载流子动力学,结果表明载流子在被激发后的3 ps内会发生一个自捕获过程.与配体辅助再沉积法相比,用热注入法制备的Cs_(3)Bi_(2)Br_(9)纳米晶具有更好的光稳定性.基于Cs_(3)Bi_(2)Br_(9)纳米晶的光电探测器具有灵敏的光响应,显示出其在光电探测方面的应用潜力. 展开更多
关键词 lead-free perovskites bismuth perovskites NANOCRYSTALS hot injection PHOTOSTABILITY
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Numerical investigations on performance improvement mechanism of a high-power vertical centrifugal pump with special emphasis on hydraulic component matching
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作者 Gang Yang xi shen +3 位作者 De-sheng Zhang Wen-hua Luo Jia Meng Xu-tao Zhao 《Journal of Hydrodynamics》 SCIE EI CSCD 2023年第4期649-667,共19页
The purpose of this paper is to investigate the performance improvement mechanism of a high power vertical centrifugal pump by using numerical calculations.Therefore,a comparative study of energy losses and internal f... The purpose of this paper is to investigate the performance improvement mechanism of a high power vertical centrifugal pump by using numerical calculations.Therefore,a comparative study of energy losses and internal flow characteristics in the original and optimized models was carried out with special attention to the hydraulic component matching.The optimized model(model B)was obtained by optimizing the vaned diffuser and volute based on the original model(model A),mainly the diffuser inlet diameter,diffuser inlet vane angle,volute channel inlet width and volute throat area were changed.Firstly,the comparative results on performance and energy losses of two models showed that the efficiency and head of model B was significantly increased under design and part-load conditions.It is mainly due to the dramatic reduction of energy loss PL in the diffuser and volute.Then,the comparisons of PL and flow patterns in the vaned diffuser showed that the matching optimization between the model B impeller outlet flow angle and diffuser inlet vane angle resulted in a better flow pattern in both the circumferential and axial directions of the diffuser,which leads to the PL3 reduction.The meridian velocity Vm of model B was significantly increased at diffuser inlet regions and resulted in improvements of flow patterns at diffuser middle and outlet regions as well as pressure expansion capacity.Finally,the comparisons of PL and flow characteristics in the volute showed that the turbulence loss reduction in the model B volute was due to the flow pattern improvement at diffuser outlet regions which provided better flow conditions at volute inlet regions.The matching optimization between the diffuser and volute significantly reduced the turbulence loss in volute sections 1–4 and enhanced the pressure expansion capacity in sections 8–10. 展开更多
关键词 High-power vertical centrifugal pump performance improvement mechanism hydraulic component matching flow pattern energy balance equation
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Identification of atypical T4SS effector proteins mediating bacterial defense
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作者 xi shen Zixiang Yang +9 位作者 Zihan Li Dan xiong Jinxing Liao Weimei He Danyu shen xiaolong Shao Ben Niu Yongxing He Yong-Gui Gao Guoliang Qian 《mLife》 CSCD 2023年第3期295-307,共13页
To remain competitive,proteobacteria use various contact-dependent weapon systems to defend against microbial com-petitors.The bacterial-killing type IV secretion system(T4SS)is one such powerful weapon.It commonly co... To remain competitive,proteobacteria use various contact-dependent weapon systems to defend against microbial com-petitors.The bacterial-killing type IV secretion system(T4SS)is one such powerful weapon.It commonly controls the killing/competition between species by secreting the lethal T4SS effector(T4E)proteins carrying conserved XVIPCD domains into competing cells.In this study,we sought knowledge to understand whether the bacterial-killing T4SS-producing bacteria encode T4E-like proteins and further explore their biological functions.To achieve this,we designed a T4E-guided approach to discover T4E-like proteins that are designated as atypical T4Es.Initially,this approach required scientists to perform simple BlastP search to identify T4E homologs that lack the XVIPCD domain in the genomes of T4SS-producing bacteria.These homologous genes were then screened in Escherichia coli to identify antibacterial candidates(atypical T4Es)and their neighboring detoxification proteins,followed by testing their gene cotranscription and validating their physical interactions.Using this approach,we did discover two atypical T4E proteins from the plant-beneficial Lysobacter enzymogenes and the phytopathogen Xanthomonas citri.We also provided substantial evidence to show that the atypical T4E protein Le1637-mediated bacterial defense in interspecies interactions between L.enzymogenes and its competitors.Therefore,the newly designed T4E-guided approach holds promise for detecting functional atypical T4E proteins in bacterial cells. 展开更多
关键词 atypical effectors DEFENSE immunity protein T4SS TOXIC
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Tree‑Inspired Structurally Graded Aerogel with Synergistic Water,Salt,and Thermal Transport for High‑Salinity Solar‑Powered Evaporation
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作者 xiaomeng Zhao Heng Zhang +3 位作者 Kit‑Ying Chan xinyue Huang Yunfei Yang xi shen 《Nano-Micro Letters》 SCIE EI CAS 2024年第11期19-37,共19页
Solar-powered interfacial evaporation is an energy-efficient solution for water scarcity.It requires solar absorbers to facilitate upward water transport and limit the heat to the surface for efficient evaporation.Fur... Solar-powered interfacial evaporation is an energy-efficient solution for water scarcity.It requires solar absorbers to facilitate upward water transport and limit the heat to the surface for efficient evaporation.Furthermore,downward salt ion transport is also desired to prevent salt accumulation.However,achieving simultaneously fast water uptake,downward salt transport,and heat localization is challenging due to highly coupled water,mass,and thermal transport.Here,we develop a structurally graded aerogel inspired by tree transport systems to collectively optimize water,salt,and thermal transport.The arched aerogel features root-like,fan-shaped microchannels for rapid water uptake and downward salt diffusion,and horizontally aligned pores near the surface for heat localization through maximizing solar absorption and minimizing conductive heat loss.These structural characteristics gave rise to consistent evaporation rates of 2.09 kg m^(-2) h^(-1) under one-sun illumination in a 3.5 wt%NaCl solution for 7 days without degradation.Even in a high-salinity solution of 20 wt%NaCl,the evaporation rates maintained stable at 1.94 kg m^(-2) h^(-1) for 8 h without salt crystal formation.This work offers a novel microstructural design to address the complex interplay of water,salt,and thermal transport. 展开更多
关键词 Composite aerogel Graded structure Solar-powered evaporation Thermal insulation Salt rejection
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Dynamic observation of oxygen vacancies in hafnia layer by in situ transmission electron microscopy 被引量:2
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作者 Chao Li Yuan Yao +6 位作者 xi shen Yanguo Wang Junjie Li Changzhi Gu Richeng Yu Qi Liu Ming Liu 《Nano Research》 SCIE EI CAS CSCD 2015年第11期3571-3579,共9页
套住费用的进程,作为捕获费用的层与 HfO <sub>2</sub> 拍摄,被在积极外部偏爱下面在 situ 电子精力损失光谱学并且在 situ 精力过滤器图象使用调查了。结果证明氧空缺在整个在编程过程期间套住层的 HfO <sub>2<... 套住费用的进程,作为捕获费用的层与 HfO <sub>2</sub> 拍摄,被在积极外部偏爱下面在 situ 电子精力损失光谱学并且在 situ 精力过滤器图象使用调查了。结果证明氧空缺在整个在编程过程期间套住层的 HfO <sub>2</sub> 是非一致地分布式的。氧空缺的分发不与套住的电子的报导地点的一样,暗示套住的过程是更复杂的。这些导致偏爱的氧缺点可以影响象设备一生那样的设备表演特征。这现象应该在套住过程的模型被考虑。 展开更多
关键词 透射电子显微镜 HFO2薄膜 氧空位 原位 电子能量损失谱 设备寿命 非均匀分布 编程过程
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