检索结果-南通市图书馆

Surface characteristics of HA coated Ti-Hf binary alloys after nanotube formation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中国有色金属学会会刊：英文版 2009年第4期19卷 852-856页

作者： Yong-Hoon JEONG Won-gi KIM Geun-Hyeong park Han-Cheol CHOE Yeong-Mu KO Department of Dental Materials & Research Center of Nano-Interface Activation for Biomaterials College of DentistryChosun University Research Center for Oral Disease Regulation of the Aged College of DentistryChosun University

Ti-Hf binary alloys contained 10%,20%,30% and 40%(mass fraction)Hf were manufactured in the vacuum furnace *** then,specimens were homogenized for 24 h at 1 000 ℃ in argon *** formation of oxide nanotubes was conducted by anodic oxidation on the Ti-Hf alloy in 1 mol/L H3PO4 electrolytes containing small amounts of NaF at room *** hydroxyapatite(HA) coating made of tooth ash prepared by electron-beam physical vapor deposition(EB-PVD) *** corrosion behaviors of the specimens were examined through potentiodynamic test in 0.9% NaCl solution by *** microstructures of the alloys were examined by field emission scanning electron microscopy(FE-SEM) and x-ray diffractometer(XRD).It was observed that the lamellar structure translated to needle-like structure with Hf *** formed and HA coated Ti-xHf alloys had a good corrosion resistance.

关键词：二元合金 HA涂层纳米管表面特性管形 0.9%NaCl溶液物理气相沉积铪

A feasible route to produce 1.1 GPa ferritic-based low-Mn lightweight steels with ductility of 47%

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2022年第22期117卷 225-237页

作者： Kwang Kyu Ko Hyo Ju Bae Eun Hye park Hyeon-Uk Jeong Hyoung Seok park Jae Seok Jeong Jung gi Kim Hyokyung Sung Nokeun park Jae Bok Seol Department of Materials Engineering and Convergence Technology Center for K-metalGyeongsang National University(GNU)Jinju 52828South Korea School of Materials Science and Engineering Yeungnam UniversityGyeongbuk 38541South Korea Materials Research Team R&D Hyundai MobisYongin 16891South Korea Materials Technology Development Team Doosan Heavy Industries&ConstructionChangwon 51711South Korea

High- and medium-Mn (H/M-Mn) base lightweight steels are a class of ultrastrong structural materials with high ductility compared to their low-Mn counterparts with low strength and poor ***, producing these H/M-Mn materials requires the advanced or high-tech manufacturing techniques, which can unavoidably provoke labor and cost concerns. Herein, we have developed a facilestrategy that circumvents the strength–ductility trade-off in low-Mn ferritic lightweight steels, by employing low-temperature tempering-induced partitioning (LTP). This LTP treatment affords a typical Fe-2.8Mn-5.7Al-0.3C (wt.%) steel with a heterogeneous size-distribution of metastable austenite embeddedin a ferrite matrix for partitioning more carbon into smaller austenite grains than into the larger austenite ones. This size-dependent partitioning results in slip plane spacing modification and lattice strain,which act through dislocation engineering. We ascribe the simultaneous improvement in strength andtotal elongation to both the size-dependent dislocation movement in austenite grains and the controlleddeformation-induced martensitic transformation. The low-carbon-partitioned large austenite grains increase the strength and ductility as a consequence of the combined martensitic transformation andhigh dislocation density-induced hardening and by interface strengthening. Additionally, high-carbonpartitioned small austenite grains enhance the strength and ductility by planar dislocation glide (inthe low strain regime) and by cross-slipping and delayed martensitic transformation (in the high strainregime). The concept of size-dependent dislocation engineering may provide different pathways for developing a wide range of heterogeneous-structured low-Mn lightweight steels, suggesting that LTP maybe desirable for broad industrial applications at an economic cost.

关键词： Low-Mn lightweight steel Carbon partitioning Metastable austenite Dislocation movement

Synergetic effects of shock waves with polydeoxyribonucleotides on rotator cuff tendon tear in a rabbit model

在线全文

学校读者我要写书评

暂无评论

BIOCELL 2021年第3期45卷 527-536页

作者： DONG HAN KIM DONG RAK KWON gi-YOUNG park YONG SUK MOON Department of Rehabilitation Medicine Catholic University of Daegu School of MedicineDaegu42472South Korea Department of Anatomy Catholic University of Daegu School of MedicineDaegu42472South Korea

This work aimed to investigate the synergetic therapeutic effects of polydeoxyribonucleotides(PDRN)combined with extracorporeal shock waves therapy(ESWT)and the effects of the therapy according to ESWT sequences on a chronic traumatic full-thickness rotator cuff tear(RCT)in rabbit *** this purpose,thirty-two rabbits were randomly allocated into 4 *** excision was made to create a 5-mm sized full-thickness RCT right proximal to the insertion site on the *** 6 weeks,4 different procedures(normal saline,Group 1;PDRN injection,Group 2;PDRN injection before ESWT,Group 3;PDRN injection after ESWT,Group 4)were *** injection and radial type ESWT were each performed 4 times per *** morphology,Immunohistochemistry,and motion analysis were performed at 4 weeks after *** parameters including tear size,Masson’s trichrome(MT)staining,anti-collagen 1 monoclonal antibody immunostaining(COL-1),proliferating cell nuclear antigen(PCNA),vascular endothelial growth factor(VEGF),anti-platelet endothelial cell adhesion molecule-1 polyclonal antibody(PECAM-1),and motion analysis,were significantly greater in Group 2,Group 3,and Group 4 than in Group *** Group 4,all parameters were significantly greater than in Group 2,and parameters including MT staining,COL-1,PCNA,PECAM-1,and fast walking time were significantly greater than Group *** were no significant differences between Group 2 and Group *** study demonstrated that PDRN injection alone and combined with ESWT were more effective than control treatment and applying ESWT before PDRN injection was also shown to yield better outcomes in parameters including angiogenesis,cell proliferation,and fast walking time in a rabbit model with chronic traumatic full-thickness ***,the application of ESWT before PDRN injection could be recommended for optimal outcomes of the conservative treatments when the patients with full-thickness RCT are not suitable in surgical treatment

关键词： Shoulder Rotator cuff Polydeoxyribonucleotides Extracorporeal shock waves

Risk factors of electrocoagulation syndrome after esophageal endoscopic submucosal dissection

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2018年第10期24卷 1144-1151页

作者： dae Won Ma Young Hoon Youn Da Hyun Jung Jae Jun park Jie-Hyun Kim Hyojin park Department of Internal Medicine Gangnam Severance Hospital Yonsei University College of Medicine

AIM To investigate post endoscopic submucosal dissection electrocoagulation syndrome(PEECS) of the *** We analyzed 55 consecutive cases with esophageal endoscopic submucosal dissection for superficial esophageal squamous neoplasms at a tertiary referral hospital in South Korea. Esophageal PEECS was defined as "mild" meeting one of the following criteria without any obvious perforation: fever(≥ 37.8 ℃), leukocytosis(> 10800 cells/μl), or regional chest pain more than 5/10 points as rated on a numeric pain intensity scale. The grade of PEECS was determined as "severe" when meet two or more of above *** We included 51 cases without obvious complications in the analysis. The incidence of mild and severe esophageal PEECS was 47.1% and 17.6%, respectively. Risk factor analysis revealed that resected area, procedure time, and muscle layer exposure were significantly associated with PEECS. In multivariate analysis, a resected area larger than 6.0 cm^2(OR = 4.995, 95%CI: 1.110-22.489, P = 0.036) and muscle layer exposure(OR = 5.661, 95%CI: 1.422-22.534, P = 0.014) were independent predictors of esophageal PEECS. All patients with PEECS had favorable outcomes with conservative management approaches, such as intravenous hydration or *** Clinicians should consider the possibility of esophageal PEECS when the resected area exceeds 6.0 cm^2 or when the muscle layer exposure is noted.

关键词： Electrocoagulation Endoscopic submucosal dissection Esophageal neoplasm Syndrome

Anaphylactic shock induced by polyethylene glycol after bowel preparation for the colorectal cancer surgery:A case report

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

世界临床病例杂志 2023年第23期11卷 5589-5594页

作者： Go Woon park Nahyeon park Jung Cheol Kuk Eung Jin Shin dae Ro Lim Department of General Surgery Soonchunhyang Bucheon HospitalBucheon 14584South Korea

BACKGROUND Polyethylene glycol(PEG)is widely used as an additive because of its hydrophilic and chemically inert ***,there are been increasing reports of PEG allergies,including anaphylaxis,although they are still *** case report aims to raise awareness,that the commonly used bowel cleansing agent containing PEG can cause serious allergic *** SUMMARY Prior to surgery for sigmoid colon cancer,a 63-year-old man was prescribed a bowel cleansing agent containing *** 30 min of ingestion,he developed symptoms of anaphylactic shock and did not respond to initial intramuscular epinephrine *** diagnosis of anaphylaxis to PEG,he was stabilized with fluid hydration and continuous norepinephrine *** While allergic reactions to PEG are rare,they can be ***,it is crucial for clinicians to be aware of this possibility and to diagnose and resuscitate patients immediately.

关键词： Polyethylene glycol Anaphylaxis Sigmoid colon cancer Bowel preparation Case report

Comparative study of tensile and high-cycle fatigue properties of extruded AZ91 and AZ91-0.3Ca-0.2Y alloys

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2021年第34期93卷 41-52页

作者： Ye Jin Kim Young Min Kim Seong-Gu Hong dae Woong Kim Chong Soo Lee Sung Hyuk park School of Materials Science and Engineering Kyungpook National UniversityDaegu 41566Republic of Korea Implementation Research Division Korea Institute of Materials ScienceChangwon 51508Republic of Korea Division of Industrial Metrology Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Energy Infra Material Measure Team Korea Research Institute of Standards and ScienceDaejeon 34113Republic of Korea Graduate Institute of Ferrous Technology Pohang University of Science and Technology.Pohang 37673Republic of Korea

Mg-Al-Zn-Ca-Y alloys with excellent ignition and corrosion resistances—termed SEN alloys(where the letters"S,""E,"and"N"stand for stainless,environmentally friendly,and non-flammable,respectively)—have been developed *** this study,the microstructure,tensile properties,and high-cycle fatigue properties of an extruded Mg-9.0Al-0.8Zn-0.1Mn-0.3Ca-0.2Y(SEN9)alloy are investigated and compared with those of a commercial Mg-9.0Al-0.8Zn-0.1Mn(AZ91)alloy extruded under the same *** the extruded SEN9 alloy and the extruded AZ91 alloy have a fully recrystallized structure comprising equiaxed grains,but the former has a smaller average grain size owing to the promoted dynamic recrystallization during *** extruded AZ91 alloy contains coarse Mg_(17)Al_(12) discontinuous precipitate(DP)bands parallel to the extrusion direction,which are formed during its cool down after *** contrast,the extruded SEN9 alloy contains relatively fine undissolved Al_(2)Ca,Al_(8)Mn_(4)Y,and Al_(2)Y second-phase particles,which are formed during the solidification stage of the casting *** tensile strength of the extruded SEN9 alloy,which has finer grains and more abundant particles,is slightly higher than that of the extruded AZ91 ***,the difference in their strengths is relatively small because the stronger solid-solution hardening and precipitation hardening effects in the extruded AZ91alloy offset the stronger grain-boundary hardening and dispersion hardening effects in the extruded SEN9alloy to some *** tensile elongation of the extruded AZ91 alloy is significantly lower than that of the extruded SEN9 alloy because the large cracks formed in the DP bands in the former cause its premature *** the extruded SEN9 alloy has higher tensile properties than the extruded AZ91alloy,the high-cycle fatigue life and fatigue strength of the former are shorter and lower,respectively,than those of the *** DP bands in the extruded

关键词： Mg-Al-Zn-Ca-Y alloy Extrusion Tensile properties High-cycle fatigue Crack source

Transanal excision of a malignant fibrous histiocytoma of anal canal:A case report and literature review

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2008年第9期14卷 1459-1462页

作者： Beom Gyu Kim In Taik Chang Jun Seok park Yoo Shin Choi gi Hyeon Kim Eon Sub park Chang Hwan Choi Department of Surgery College of MedicineChung-Ang University Seoul 156-755Korea Department of Radiology College of MedicineChung-Ang University Seoul 156-755Korea Department of Pathology College of MedicineChung-Ang University Seoul 156-755 Korea Department of Internal Medicine College of Medicine Chung-Ang UniversitySeoul 156-755Korea

Malignant fibrous histiocytoma, which is composed of spindle-shaped cells arranged in a pleomorphic and storiform pattern, is rarely found in the colorectum. Although complete surgical excision remains the main stem of therapy, an optimal treatment strategy according to the stage has not been elucidated. We report a case of a 63-year-old woman with an ulcerative lesion in the anorectal junction and a final diagnosis of malignant fibrous histiocytoma. We introduced an access for transanal local excision and adjuvant radiotherapy because the patient refused abdominoperineal resection. No local recurrences or distant metastases were observed 15 mo after the operation. To our knowledge, this is the first case reported in the English literature of a malignant fibrous histiocytoma treated with the transana local excision and adjuvant radiotherapy. This report showed that this approach is selectively reserved for early-stage malignant fibrous histiocytoma and for those patients who refuse radical surgery because of the risk in a permanent colostomy.

关键词： Malignant fibrous histiocytoma Anorectal junction Transanal local excision

Early treadmill exercise increases macrophage migration inhibitory factor expression after cerebral ischemia/reperfusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2019年第7期14卷 1230-1236页

作者： Min Cheol Chang Chae Ri park Seung Hwa Rhie Woo Hyun Shim dae Yul Kim Department of Rehabilitation Medicine College of MedicineYeungnam University Asan Institute for Life Sciences Asan Medical CenterUniversity of Ulsan College of Medicine Department of Rehabilitation Medicine Asan Medical CenterUniversity of Ulsan College of Medicine Department of Radiology Asan Medical CenterUniversity of Ulsan College of Medicine

The neuroprotective function of macrophage migration inhibitory factor(MIF) in ischemic stroke was rarely *** study aimed to investigate the effects of early treadmill exercise on recovery from ischemic stroke and to determine whether these effects are associated with the expression levels of MIF and brain-derived neurotrophic factor(BDNF) in the ischemic area.A total of 40 male Sprague-Dawley rats were randomly assigned to the ischemia and exercise group [middle cerebral artery occlusion(MCAO)-Ex,n = 10),ischemia and sedentary group(MCAO-St,n = 10),sham-surgery and exercise group(Sham-Ex,n= 10),or sham-surgery and sedentary group(Sham-St,n = 10).The MCAO-Ex and MCAO-St groups were subjected to MCAO for 60 minutes,whereas the Sham-Ex and Sham-St groups were subjected to an identical operation without *** in the MCAO-Ex and Sham-Ex groups then ran on a treadmill for 30 minutes once a day for 5 consecutive *** reperfusion,the hanging time tested by the wire hang test was longer and the relative fractional anisotropy determined by MRI was higher in the peri-infarct region of the MCAO-Ex group compared with the MCAO-St *** expression levels of MIF and BDNF in the peri-infarct region were upregulated in the MCAO-Ex *** MIF and BDNF levels were positively correlated with relative fractional anisotropy changes in the peri-infarct *** was no significant difference in the levels of MIF and BDNF in the peri-infarct region between the Sham-Ex and Sham-St *** study demonstrated that early exercise(initiated 48 hours after the MCAO) could improve motor and neuronal recovery after ischemic ***,the increased levels of MIF and BDNF in the peri-infarct region(penumbra) may be one of the mechanisms of enhanced neurological function *** experiments were approved by the Institutional Animal Care and Use Committee in Asan Medical Center in South Korea(2016-12-126).

关键词： ischemic stroke early exercise macrophage migration inhibitory factor brain-derived neurotrophic factor motor recovery neural regeneration

Expression of prothymosin α predicts early recurrence and poor prognosis of hepatocellular carcinoma

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic Diseases International 2015年第2期14卷 171-177页

作者： Sang Yun Ha dae Hyun Song Soo Hyun Hwang Soo Youn Cho Cheol-Keun park Department of Pathology Samsung Medical CenterSungkyunkwan University School of Medicine

BACKGROUND：Prothymosinα（PTMA）is a nuclear oncoprotein-transcription factor essential for cell cycle progression and *** was overexpressed in several human malignancies including hepatocellular carcinoma（HCC）.However,the prognostic significance of PTMA protein expression in HCC remains *** the present study,we evaluated PTMA protein expression by immunohistochemistry in order to elucidate the prognostic roles of PTMA in HCC ***： By immunohistochemistry, we investigated the expression of PTMA protein in tumor tissue from 226 HCC patients who underwent curative hepatectomy. Univariate and multivariate analyses were performed to evaluate its predic- tive value for tumor recurrence and survival of patients. The median follow-up period was 120 months. RESULTS： PTMA expression was observed in 162 （71.7%） of the 226 HCC patients and was significantly associated with higher Edmondson grade, microvascular invasion, intrahe- patic metastasis, higher American Joint Committee on Cancer （AJCC） T-stage, and lower albumin level. PTMA expression was an independent predictor of early recurrence （P=0.001）. PTMA expression showed an unfavorable influence on recurrence- free survival （RFS）（P〈0.001）. Subgroup analysis showed that among patients with tumor size _〈5.0 cm （140 patients）, patients at AJCC T-stage I （95 patients） and patients with a-fetoprotein ≤20 ng/mL （83 patients）, the differences in RFS between PTMA- positive and PTMA-negative groups were also statistically sig- nificant （P=0.017, P=0.002 and P=0.002, respectively）. In addi- tion, PTMA expression was an independent predictor of shorter RFS （P=0.011）. PTMA expression showed an unfavorable influ- ence on overall survival （P=0.014）, but was not an independent predictor of shorter overall survival （P=0.161）. CONCLUSIONS： PTMA protein expression might be a novel predictor of early recurrence and RFS in HCC patients, even those at early stage or with a-fetoprotein-negative after curative hep

关键词： prothymosin a hepatocellular carcinoma recurrence