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Is the neutrophil to lymphocyte ratio associated with liver fibrosis in patients with chronic hepatitis B? 被引量:15
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作者 Murat Kekilli Alpaslan Tanoglu +3 位作者 Yusuf Serdar Sakin Mevlut Kurt Serkan Ocal Sait Bagci 《World Journal of Gastroenterology》 SCIE CAS 2015年第18期5575-5581,共7页
AIM: To determine the association between the neutrophil to lymphocyte(N/L) ratio and the degree of liver fibrosis in patients with chronic hepatitis B(CHB) infection. METHODS: Between December 2011 and February 2013,... AIM: To determine the association between the neutrophil to lymphocyte(N/L) ratio and the degree of liver fibrosis in patients with chronic hepatitis B(CHB) infection. METHODS: Between December 2011 and February 2013, 129 consecutive CHB patients who were admitted to the study hospitals for histological evaluation of chronic hepatitis B-related liver fibrosis were included in this retrospective study. The patients were divided into two groups based on the fibrosis score: individuals with a fibrosis score of F0 or F1 were included in the "no/minimal liver fibrosis" group, whereas patients with a fibrosis score of F2, F3, or F4 were included in the "advanced liver fibrosis" group. The Statistical Package for Social Sciences 18.0 for Windows was used to analyze the data. A P value of < 0.05 was accepted as statistically significant.RESULTS: Three experienced and blinded pathologists evaluated the fibrotic status and inflammatory activity of 129 liver biopsy samples from the CHB patients. Following histopathological examination, the "no/minimal fibrosis" group included 79 individuals, while the "advanced fibrosis" group included 50 individuals. Mean(N/L) ratio levels were notably lower in patients with advanced fibrosis when compared with patients with no/minimal fibrosis. The mean value of the aspartate aminotransferase-platelet ratio index was markedly higher in cases with advanced fibrosis compared to those with no/minimal fibrosis.CONCLUSION: Reduced levels of the peripheral blood N/L ratio were found to give high sensitivity, specificity and predictive values in CHB patients with significant fibrosis. The prominent finding of our research suggests that the N/L ratio can be used as a novel noninvasive marker of fibrosis in patients with CHB. 展开更多
关键词 Chronic HEPATITIS B Liver FIBROSIS NEUTROPHIL to LYMPHOCYTE ratio Fibrotic stage Inflammatory activity NON-INVASIVE marker
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A bibliometric analysis of academic publication on diabetic retinopathy disease trends during 1980-2014:a global and medical view 被引量:7
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作者 Cagatay Caglar Emre Demir +1 位作者 Ferit Kerim Kucukler Mustafa Durmus 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2016年第11期1663-1668,共6页
AIM: To investigate diabetic retinopathy(DR) literature using the Institute for Scientific Information(ISI) Web of Science(Wo S) database and to analyse the correlation results between socio-economic developmen... AIM: To investigate diabetic retinopathy(DR) literature using the Institute for Scientific Information(ISI) Web of Science(Wo S) database and to analyse the correlation results between socio-economic development datas and number of DR publications.METHODS: The statistical analysis of the documents published during 1980-2014 was analysed. The data of this study were based on the database of Wo S. "Diabetic retinopathy" was used as the keywords to search the Wo S database.RESULTS: The United States ranked first in the DR research with 1840 publications and 24.38% of the world production followed by England and Japan. Besides, the most productive country was Iceland. A high correlation was found between number of publications and 2014 gross domestic product( GDP) values of 81 countries(r =0.800, P 〈0.001). We found a significant correlation between number of publications and Human Development Index(HDI)(r =0.645, P =0.001). There is a moderate correlation between people with diabetes and number of DR publications for 81 countries(r =0.514, P 〈0.01). It could be analysed that estimated publication number with DR title will be 445 according to the regression curve constituted with cubic model in 2015(R2=1.000).CONCLUSION: More DR studies have been published in developed countries, DR and other complications of diabetes have gradually increased in developing countries over recent decades. It can be expected that the number of DR studies will gradually increase in developing countries. 展开更多
关键词 BIBLIOMETRICS correlation analysis developingcountries diabetic retinopathy socio-economic development
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Structural,morphological and magnetic properties of(Ni_(0.5)Co_(0.5))[Ga_(x)Gd_(x)Fe_(2-2x)]O_(4)nanoparticles prepared via sonochemical approach
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作者 Y.Slimani M.A.Almessiere +5 位作者 A.Demir Korkmaz A.Baykal M.A.Gondal H.Güngünes Sagar E.Shirsath A.Manikandan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2023年第4期561-571,共11页
The impact of Ga^(3+)and Gd^(3+)co-substitution on different types of behavior of Ni-Co nanospinel ferrites(NSFs),(Ni_(0.5)Co_(0.5))[Ga_(x)Gd_(x)Fe_(2-2x)]O_(4)(0.000≤x≤0.025),was investigated.NSFs were fabricated t... The impact of Ga^(3+)and Gd^(3+)co-substitution on different types of behavior of Ni-Co nanospinel ferrites(NSFs),(Ni_(0.5)Co_(0.5))[Ga_(x)Gd_(x)Fe_(2-2x)]O_(4)(0.000≤x≤0.025),was investigated.NSFs were fabricated through ultrasound irradiation.The structure,composition,and spherical morphology of all products were verified by numerous characterization techniques such as X-ray diffraction(XRD),scanning and transmission electron microscopes(SEM and TEM),and selected area electron diffraction(SAED).Mossbauer spectra are composed of two ferromagnetic sextets and one paramagnetic doublet.These spectra were fitted to extract hyperfine parameters of the doped samples.Both sublattices'hyperfine magnetic field decreases with substitution.The isomer shift values show that the Mossbauer spectra are composed of magnetic Fe^(3+)sextets.The magnetization measurements at variable magnetic field(M-H)were investigated via a vibrating sample magnetometer(VSM)at temperatures(T)from 300 to 10 K.All NSFs disclose ferrimagnetic behavior at both 300 and 10 K at which they are soft and hard,respectively.We determined that the remanence magnetization(M_(r)),saturation magnetization(M_(s)),and magneton number(n_(B))decrease with increasing Ga^(3+)and Gd^(3+)ions contents.The reduction in these values is predominantly recognized to be the impact of cation redistribution and surface spins on tetrahedral(T_(d))and octahedral(O_(h))sites.As the Ga^(3+)and Gd^(3+)contents increase,the coercivity(H_(c))is also found to decrease. 展开更多
关键词 Spinel ferrites Rare earth substitution Sonochemical synthesis Mossbauer analysis Magnetic properties
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One-step electrochemical reduction of stibnite concentrate in molten borax 被引量:6
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作者 Levent Kartal Mehmet Baris Daryal +1 位作者 Güldem Kartal Sireli Servet Timur 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第10期1258-1265,共8页
In this study,antimony production from a stibnite concentrate(Sb2S3)was performed in one step using a molten salt electrolysis method and borax as an electrolyte.Electrochemical reduction of the stibnite concentrate w... In this study,antimony production from a stibnite concentrate(Sb2S3)was performed in one step using a molten salt electrolysis method and borax as an electrolyte.Electrochemical reduction of the stibnite concentrate was performed at 800℃under galvanostatic conditions and explained in detail by the reactions and intermediate compounds formed in the borax.The effects of current density(100 800 mA cm^-2)and electrolysis time(10 40 min)on cathodic current efficiency and antimony yields were systematically investigated.During the highest current efficiency,which was obtained at 600 mA cm^-2,direct metal production was possible with 62%cathodic current efficiency and approximately 6 kWh/kg energy consumption.At the end of the 40-min electrolysis duration at 600 mA cm^-2 current density,antimony reduction reached 30.7 g and 99%of the antimony fed to the cell was obtained as metal. 展开更多
关键词 MOLTEN salt ELECTROLYSIS electrochemical reduction ANTIMONY ANTIMONY extraction STIBNITE BORAX
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Low temperature thermoluminescence behaviour of Y_2O_3 nanoparticles 被引量:4
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作者 S.Delice M.Isik N.M.Gasanly 《Journal of Rare Earths》 SCIE EI CAS CSCD 2019年第1期19-23,M0002,共6页
Y_2O_3 nanoparticles were investigated using low temperature thermoluminescence (TL) experiments. TL glow curve recorded at constant heating rate of 0.4 K/s exhibits seven peaks around 19, 62, 91,115,162,196 and 215 K... Y_2O_3 nanoparticles were investigated using low temperature thermoluminescence (TL) experiments. TL glow curve recorded at constant heating rate of 0.4 K/s exhibits seven peaks around 19, 62, 91,115,162,196 and 215 K. Activation energies and characteristics of traps responsible for observed curves were revealed under the light of results of initial rise analyses and T_(max)-T_(stop) experimental methods. Analyses of TL curves obtained at different stopping temperatures resulted in presence of one quasi-continuously distributed trap with activation energies increasing from 18 to 24 meV and six single trapping centers at49, 117, 315, 409, 651 and 740 meV. Activation energies of all revealed centers were reported in the present paper. Structural characterization of Y_2O_3 nanoparticles was accomplished using X-ray diffraction and scanning electron microscopy measurements. 展开更多
关键词 Y2O3 LUMINESCENCE THERMOLUMINESCENCE DEFECTS RARE earths
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Peripapillary and macular vascular densities in healthy,ocular hypertensive,and different stages of glaucomatous eyes
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作者 Caner Ozturk Sirel Gur Gungor +2 位作者 Umit Eksioglu Almila Sarıgul Sezenoz Meric Colak 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2023年第12期2018-2026,共9页
AIM:To investigate vascular changes in different stages of glaucoma and to evaluate the role of optical coherence tomography angiography(OCTA)in the early diagnosis of glaucoma.METHODS:Glaucoma patients and healthy co... AIM:To investigate vascular changes in different stages of glaucoma and to evaluate the role of optical coherence tomography angiography(OCTA)in the early diagnosis of glaucoma.METHODS:Glaucoma patients and healthy controls(n=29 eyes)were investigated in this cross-sectional comparative study.Glaucoma patients were grouped as ocular hypertension(n=44 eyes),preperimetric glaucoma(PPG;n=32 eyes),early glaucoma(EG;n=35 eyes),moderate stage glaucoma(MG;n=36 eyes),and advanced glaucoma(AG;n=35 eyes).Peripapillary and macular vascular densities(VDs)of all participants were compared and correlations of VDs and retinal nerve fiber layer thickness(RNFLT),ganglion cell analysis(GCA),and visual field(VF)tests were evaluated.Area under the receiver operation characteristic curves(AUC)of the peripapillary and macular VD parameters were obtained.RESULTS:VD values decreased with the progression of glaucoma.Most peripapillary and macular VD parameters of PPG and EG groups were lower than healthy controls(P<0.001).There was no significant difference in RNFLT between the PPG and EG groups,but most peripapillary and macular VDs were found to be lower in EG group than in PPG group(P<0.05).In most disease group,VDs were significantly correlated with OCT parameters(P<0.001)and VF index(P<0.05).There were no significant correlations between VF and RNFLT indices in the AG group,but significant correlations were found between VF and VD values(P<0.05).AUC for discriminating between healthy and glaucomatous eyes were highest in whole image peripapillary VD(AUC:0.865,0.929,and 0.986,respectively in EG,MG,and AG groups).CONCLUSION:OCTA can be used in the early diagnosis of glaucoma and can be useful in follow-up of the advanced disease.In cases where limitations or suspicions in structural and functional tests are present,OCTA can be used as a supportive diagnostic test,both in EG and AG. 展开更多
关键词 glaucoma optical coherence tomography angiography vascular density early diagnosis
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Direct electrochemical reduction of copper sulfide in molten borax 被引量:4
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作者 Levent Kartal Servet Timur 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第8期992-998,共7页
In this study,for the first time,direct copper production from copper sulfide was carried out via direct electrochemical reduction method using inexpensive and stable molten borax electrolyte.The effects of current de... In this study,for the first time,direct copper production from copper sulfide was carried out via direct electrochemical reduction method using inexpensive and stable molten borax electrolyte.The effects of current density(100–800 mA/cm^2)and electrolysis time(15–90 min)on both the cathodic current efficiency and copper yield were systematically investigated in consideration of possible electrochemical/chemical reactions at 1200℃.The copper production yield reached 98.09%after 90 min of electrolysis at a current density of 600 mA/cm^2.Direct metal production was shown to be possible with 6 kWh/kg energy consumption at a 600 mA/cm2 current density,at which the highest current efficiency(41%)was obtained.The suggested method can also be applied to metal/alloy production from single-and mixed-metal sulfides coming from primary production and precipitated sulfides,which are produced in the mining and metallurgical industries during treatment of process solutions or wastewaters. 展开更多
关键词 MOLTEN salt ELECTROLYSIS ELECTRO-REDUCTION COPPER extraction COPPER SULFIDE BORAX
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Colorectal stenting for palliation and as a bridge to surgery:A 5-year follow-up study 被引量:3
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作者 Baris Bayraktar Ibrahim Ali Ozemir +6 位作者 Umut Kefeli Gokhan Demiral Julide Sagiro?lu Onur Bayraktar Gupse Adali Alp Ozcelik Osman Baran Tortum 《World Journal of Gastroenterology》 SCIE CAS 2015年第31期9373-9379,共7页
AIM: To evaluate the long-term effectiveness of colonic stents in colorectal tumors causing large bowel obstruction.METHODS: We retrospectively analyzed data from 49 patients with colorectal cancer who had undergone c... AIM: To evaluate the long-term effectiveness of colonic stents in colorectal tumors causing large bowel obstruction.METHODS: We retrospectively analyzed data from 49 patients with colorectal cancer who had undergone colorectal stent placement between January 2008 and January 2013. Patients' symptoms,characteristics and clinicopathological data were obtained by reviewing medical records. The obstruction was diagnosed clinically and radiologically. Histopathological diagnosis was achieved endoscopically. Technical success rate(TSR)was defined as the ratio of patients with correctly placed SEMS upon stent deployment across the entire stricture length to total number of patients. Clinical success rate(CSR) was defined as the ratio of patients with technical success and successful maintenance of stent function before elective surgery(regardless of number of SEMS deployed) to total number of patients. The surgical success rate(SSR) of colorectal stent as a bridge to surgery was defined as the ratio of patients with successful surgical procedures. Unsuccessful surgical outcomes were defined as being due to insufficient colonic decompression. The technical,clinical,surgical success rates and complications after stenting were assessed.RESULTS: The median age of patients was 64(36 to 89). 44.9% of patients were male and 55.1% were female. Eighteen patients had the obstruction located in the rectum,15 patients in the rectosigmoid region,10 patients in the sigmoid region,and 6 patients had a tumor causing obstruction in the proximal colon. Each patient was categorized pathologically as stage 2(32.7%,16 patients) or stage 3(42.9%,21 patients) and 12 patients(24.4%) had metastatic disease. None of the patients received chemotherapy before stenting. Stenting was undertaken in 37 patients as a bridge to surgery,and in 12 patients stents were used for palliation. Median time to surgery after stenting was 30 ± 91.9 d. All surgery was completed in one single operation and thus no colostomy with stoma was needed. The median overall 展开更多
关键词 Large bowel obstruction Colonic decom-pression Colorectal tumors Metallic stent Palliative therapy
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Gastric neuroendocrine neoplasms: A review 被引量:2
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作者 Huseyin Koseoglu Tolga Duzenli Mesut Sezikli 《World Journal of Clinical Cases》 SCIE 2021年第27期7973-7985,共13页
Gastric neuroendocrine neoplasms(g-NENs)or neuroendocrine tumors are generally slow-growing tumors with increasing incidence.They arise from enterochromaffin like cells and are divided into four types according to cli... Gastric neuroendocrine neoplasms(g-NENs)or neuroendocrine tumors are generally slow-growing tumors with increasing incidence.They arise from enterochromaffin like cells and are divided into four types according to clinical characteristic features.Type 1 and 2 are gastrin dependent,whereas type 3 and 4 are sporadic.The reason for hypergastrinemia is atrophic gastritis in type 1,and gastrin releasing tumor(gastrinoma)in type 2 g-NEN.The diagnosis of g-NENs needs histopathological investigation taken by upper gastrointestinal endoscopy.g-NENs are positively stained with chomogranin A and synaptophysin.Grading is made with mitotic index and ki-67 proliferation index on histopathological analysis.It is crucial to discriminate between types of g-NENs,because the management,treatment and prognosis differ significantly between subtypes.Treatment options for g-NENs include endoscopic resection,surgical resection with or without antrectomy,medical treatment with somatostatin analogues,netazepide or chemotherapy regimens.Follow-up without excision is another option in appropriate cases.The prognosis of type 1 and 2 g-NENs are good,whereas the prognosis of type 3 and 4 g-NENs are close to the prognosis of gastric adenocancer. 展开更多
关键词 Gastric neuroendocrine tumors Gastric neuroendocrine neoplasm Gastric neuroendocrine carcinoma HYPERGASTRINEMIA CARCINOID Somatostatin receptor imaging
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Co-substitution of zirconium and neodymium on hyperfine interactions and AC susceptibility of SrFe12O19 nanohexaferrites 被引量:2
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作者 M.A.Almessere Y.Slimani +1 位作者 H.Güngünes A.Baykal 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第3期265-273,共9页
This study presents the influence of Zn and Nd co-substitution on structure,morphology,AC susceptibility and ZFC-FC magnetizations of Sr nanohexaferrites(NHFs),SrFe12-x(Zn,Nd)xO19(0.0≤x≤1.0),which was produced by so... This study presents the influence of Zn and Nd co-substitution on structure,morphology,AC susceptibility and ZFC-FC magnetizations of Sr nanohexaferrites(NHFs),SrFe12-x(Zn,Nd)xO19(0.0≤x≤1.0),which was produced by sol-gel approach.XRD powder patterns,scanning electron microscopy(SEM) and high-resolution transmission electron spectroscopy(HR-TEM) approve the synthesis of Sr M-type hexaferrite.Mossbauer spectra show that Zn^2+ions occupy 2 b and 4f1 sites while Nd3+ions locate at 2 a,4f2 and 12 k sites.The magnetic properties of the produced Sr-NHFs were investigated also by ZFC-FC magnetizations and AC susceptibility.According to the MFC-MZFC results(between 2 and 400 K),no blocking temperature was detected which indicates the ferromagnetic(FM) behavior of NHFs.At lower temperatures,a super-spin glass like behavior is discerned.The AC susceptibility indicates that the magnetic interactions are improved due to the inclusion of low content(x=0.1) of Nd^3+and Zn^2+ions into the Sr-NHFs.However,with further increasing the Nd^3+and Zn^2+contents(x=0.9),the magnetic interactions are weakened. 展开更多
关键词 Sr HEXAFERRITES Rare earths MOSSBAUER spectroscopy AC susceptibility ZFC-FC
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Pentamidine in Pneumocystis jirovecii prophylaxis in heart transplant recipients 被引量:1
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作者 Adem Ilkay Diken Ozlem Er?en Diken +4 位作者 Onur Hanedan Seyhan Y?lmaz Ata Niyazi Ecevit Emir Erol Adnan Yal??nkaya 《World Journal of Transplantation》 2016年第1期193-198,共6页
Despite advances in transplantation techniques and the quality of post-transplantation care, opportunistic infections remain an important cause of complications. Pneumocystis jirovecii(P. jirovecii) is an opportunisti... Despite advances in transplantation techniques and the quality of post-transplantation care, opportunistic infections remain an important cause of complications. Pneumocystis jirovecii(P. jirovecii) is an opportunistic organism, represents an important cause of infections in heart transplantation patients. Almost 2% to 10% of patients undergoing cardiac transplantation have Pneumocystis pneumonia. Prophylaxis is essential after surgery. Various prophylaxis regimes had been defined in past and have different advantages. Trimethoprim/sulfamethoxazole(TMP/SMX) has a key role in prophylaxis against P. jirovecii. Generally, although TMP/SMX is well tolerated, serious side effects have also been reported during its use. Pentamidine is an alternative prophylaxis agent when TMP/SMX cannot be tolerated by the patient. Structurally, pentamidine is an aromatic diamidine compound with antiprotozoal activity. Since it is not effectively absorbed from the gastrointestinal tract, it is frequently administered via the intravenous route. Pentamidine can alternatively be administered through inhalation at a monthly dose in heart transplant recipients. Although, the efficiency and safety of this drug is well studied in other types of solid organ transplantations, there are only few data about pentamidine usage in heart transplantation. We sought to evaluate evidence-based assessment of the use of pentamidine against P. jirovecii after heart transplantation. 展开更多
关键词 PENTAMIDINE PROPHYLAXIS TRIMETHOPRIM Heart transplantation PNEUMOCYSTIS PNEUMONIA PNEUMOCYSTIS jirovecii PNEUMOCYSTIS carinii
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Clinical and Demograhical Characteristics of Patients with Maxillofacial Trauma in the Emergency Department 被引量:1
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作者 Seval Komut Bedriye Mü +3 位作者 ge Sö nmez Ali Kemal Erenler Erdal Komut 《Open Journal of Emergency Medicine》 2019年第2期28-39,共12页
Objective: We aimed to investigate the clinical and demographical characteristics of patients admitted to the Emergency Department (ED) due to maxillofacial trauma (MFT). Methods: This sectional and retrospective stud... Objective: We aimed to investigate the clinical and demographical characteristics of patients admitted to the Emergency Department (ED) due to maxillofacial trauma (MFT). Methods: This sectional and retrospective study was conducted in Ankara Numune Education and Research Hospital ED between 1st March 2010 and 31st March 2017. Into the study, patients with MFT older than 15 years of age were included. Characteristics of patients were recorded. Patients’ characteristics were compared according to presence of fractures. Results: Mean age of the patients was 41.1 ± 18.0 years and a statistically significant relationship was determined between age and presence of fracture (p > 0.05). Of the patients, 74.5% was male and fracture presence was significantly more in males than females (p 0.05). Conclusion: The MFT is a pathology that either leads to its own, or can lead to life-threatening consequences as a result of additional organ injuries. The physician evaluating the patient should determine the MFT and additional pathologies and ensure that the interventions start as soon as possible. 展开更多
关键词 MAXILLOFACIAL TRAUMA EMERGENCY DEPARTMENT MAXILLOFACIAL FRACTURE
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Biologic Agents in Behcet’s Disease:Our Experience and Review of the Literature
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作者 Nesibe Karahan Yesil Hatice Sahin +6 位作者 Hatice Isik Zuhal Irnek Serpil Yazgan Adem Tok Yunus Emre Yandi Metin Isik Ismail Dogan 《Open Journal of Rheumatology and Autoimmune Diseases》 2015年第4期97-103,共7页
Behcet’s disease (BD) is a large vessel vasculitis with a wide range of clinical manifestations. Some of these manifestation may be life threatening and rapid suppression of the inflammation with effective immunosupp... Behcet’s disease (BD) is a large vessel vasculitis with a wide range of clinical manifestations. Some of these manifestation may be life threatening and rapid suppression of the inflammation with effective immunosuppressive agent is crucial. There are traditional drugs with different response rates and all have efficacy on different manifestations of the disease. The most frightening manifestations of the disease are ocular, neurologic, intestinal and vascular types of involvement. Besides benign and easily treated manifestations there are also refractory cases with complicated involvement. The novel biologic agents have been used for these resistant patients and favorable response rates have been reported. In this review, we have shared our experience with biologic agents in BD and also reviewed the literature for the efficacy and safety for these novel agents for refractory patients. 展开更多
关键词 Behcet’s Disease Novel Biologic Agents Refractory Patients
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Reciprocating sliding wear properties of sintered Al-B_(4)C composites 被引量:1
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作者 Mahmut Can Şenel Yusuf Kanca Mevlüt Gürbüz 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第6期1261-1269,共9页
The fabrication of boron carbide reinforced aluminum matrix composites(Al-B_(4)C)with various contents of B_(4)C(1wt%,6wt%,15wt%,and 30wt%)was performed by powder metallurgy,and the influence of the content of B_(4)C ... The fabrication of boron carbide reinforced aluminum matrix composites(Al-B_(4)C)with various contents of B_(4)C(1wt%,6wt%,15wt%,and 30wt%)was performed by powder metallurgy,and the influence of the content of B_(4)C on their mechanical and tribological behavior was examined.The Al-30B_(4)C composites recorded the highest density(~2.54 g/cm^(3)),lowest porosity(4%),maximum Vickers hardness(HV~75),lowest weight loss(0.4 mg),and lowest specific wear rate(0.00042 mm^(3)/(N·m))under a load of 7 N,with an enhancement of 167%in hardness,a decrease of 75.8%in weight loss,and a decrease of 76.7%in the specific wear rate compared with pure aluminum.In addition,the scanning electron microscope images of the worn surface revealed that the Al-B_(4)C composite has the narrowest wear groove of 0.85 mm at a load of 7 N,and the main wear mechanism was observed as an abrasive wear mechanism.According to the friction analysis,the coefficient of friction between surfaces increased with increasing boron carbide content and with decreasing applied load.In conclusion,B_(4)C is an effective reinforcement material in terms of tribological and mechanical performance of the Al-B_(4)C composites. 展开更多
关键词 ALUMINUM boron carbide COMPOSITE WEAR FRICTION
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Electrolytic production of Cu-Ni alloys in CaCl_2-Cu_2S-NiS molten salt 被引量:2
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作者 Levent KARTAL Servet TIMUR 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第10期2143-2150,共8页
An alternative metal/alloy production method,known as direct electrochemical reduction(DER),was introduced for the fabrication of CuNi alloys from mixed sulfides(Cu2S,NiS)under both galvanostatic and potentiostatic co... An alternative metal/alloy production method,known as direct electrochemical reduction(DER),was introduced for the fabrication of CuNi alloys from mixed sulfides(Cu2S,NiS)under both galvanostatic and potentiostatic conditions.The influences of the process parameters(e.g.,cell voltage and current)on the compositions of the reduced compounds were investigated to yield industrially desirable alloys,namely,CuNi10,CuNi20,and CuNi30.The electrochemical behaviors of Cu2S and NiS in CaCl2 melt were examined at a temperature of 1200°C via cyclic voltammetry(CV).Based on the CV results,the cathodic reduction of Cu2S occurred in one step and cathodic reductions of NiS occurred in two steps,i.e.,Cu2S?Cu for copper reduction and NiS?Ni3S2?Ni for nickel reduction.Galvanostatic studies revealed that it was possible to fabricate high-purity CuNi10 alloys containing a maximum sulfur content of 320×10-6 via electrolysis at 10 A for 15 min.Scanning electron microscopy along with energy-dispersive X-ray spectrometry and optical emission spectroscopy(OES)examinations showed that it was possible to fabricate CuNi alloys of preferred compositions and with low levels of impurities,i.e.,less than 60×10-6 sulfur,via DER at 2.5 V for 15 min. 展开更多
关键词 molten salt electrolysis ELECTRO-REDUCTION copper extraction copper sulfide nickel sulfide Cu-Ni alloys
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Tb^(3+)substituted strontium hexaferrites:Structural,magnetic and optical investigation and cation distribution 被引量:1
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作者 M.A.Almessiere Y.Slimani +5 位作者 H.Gungunes M.Sertkol M.Nawaz N.A.Algarou A.Baykal I.Ercan 《Journal of Rare Earths》 SCIE EI CAS CSCD 2020年第4期402-410,共9页
In this study,SrFe12-xTbxO19(0.00≤x≤0.1)hexaferrites(HFs)were prepared successfully by citrate solgel approach.X-ray powder diffraction analyses affirm the hexagonal structure of products.Impurity phase starts to ap... In this study,SrFe12-xTbxO19(0.00≤x≤0.1)hexaferrites(HFs)were prepared successfully by citrate solgel approach.X-ray powder diffraction analyses affirm the hexagonal structure of products.Impurity phase starts to appear for x≥0.04.The crystallites sizes were estimated to be in the range of 33-46 nm.All the products exhibit inhomogeneous distribution of grain size detected through SEM.The analyses of magnetization versus applied magnetic field,M(H),were performed.Magnetization measurements were done at room(300 K;RT)and low(10 K)temperatures.The different magnetic parameters including saturation magnetization Ms,remanence Mr,squareness ratio(SQR=Mr/Ms),coercivity Hc,and magnetic moment nB are deduced and discussed in detail.At both considered temperatures,M(H)results show ferrimagnetic nature for all compositions.It is shown that the Tb substitutions significantly affect M(H)data.A significant increase in the Ms,Mr,and nB is observed for x=0.02 sample.The SQR values are around 0.5 indicating the single domain nature with uniaxial anisotropy.The obtained magnetic results were investigated deeply with relation to structural and microstructural properties.Mossbauer spectroscopy results were also investigated.According to Mossbauer results,the Tb3+ions preferentially occupy 12 k and 4f2 sites. 展开更多
关键词 M-type hexaferrites Structure Mossbauer spectroscopy Optical properties MAGNETIZATION Rare earths
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Evaluation of Predictors of Suicidal Re-Attempt in Pediatric Patients in the Emergency Department
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作者 Ali Kemal Erenler Turker Yardan +1 位作者 Fuat Kulaksiz Cem Kocak 《Open Journal of Pediatrics》 2017年第4期309-319,共11页
Background: Suicidal attempt in children is a serious public health problem. A proper identification of features of suicide-related behavior may help physicians to develop an accurate approach. The aim of this study w... Background: Suicidal attempt in children is a serious public health problem. A proper identification of features of suicide-related behavior may help physicians to develop an accurate approach. The aim of this study was to clarify the characteristics of children with poisoning due to suicidal attempt and to determine the risk factors of suicidal re-attempt in the Emergency Department (ED) via a simple questionnaire. Methods: We collected medical data of patients under 18 years who were admitted to our ED with intoxication due to suicidal attempt, retrospectively. General characteristics of patients were evaluated. Patients were divided into 2 groups as 1) High risk: patients with repetitive suicide attempt;2) Low risk: patients with first time suicidal attempt. Results: A total of 57 patients were included in this study. The mean age was 15.91 ± 0.97. Majority of the patients were female (73.7%). Analgesics were the most frequent abused drugs with a ratio of 51.1%. It is determined that the most important variables affecting the risk of suicidal re-attempt are “idea about the suicide” and “purpose”. It was determined that patients with an idea of repetitive suicide (I will try again) and whose purpose was to die (I wish I have died) were in the most risky group with a history of previous suicidal attempt. Conclusion: This study suggests that answers of the pediatric patients to some question have a potential to predict the high risk patients. The risk of suicidal re-attempt may be predicted by the answers given to these questions: 1) What is your idea about suicide? 2) What was your purpose? 展开更多
关键词 SUICIDE Pediatric Patients Emergency Department
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Impact of different sampling rates on precise point positioning performance using online processing service 被引量:1
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作者 Serdar Erol Reha Metin Alkan +1 位作者 İ.Murat Ozulu Veli Ilçi 《Geo-Spatial Information Science》 SCIE CSCD 2021年第2期302-312,I0008,共12页
In this study,the effect of different sampling rates(i.e.observation recording interval)on the Precise Point Positioning(PPP)solutions in terms of accuracy was investigated.For this purpose,a field test was carried ou... In this study,the effect of different sampling rates(i.e.observation recording interval)on the Precise Point Positioning(PPP)solutions in terms of accuracy was investigated.For this purpose,a field test was carried out inÇorum province,Turkey,on 11 September 2019.Within this context,a Geodetic Point(GP)was established and precisely coordinated.A static GNSS measurement was occupied on the GP for about 4-hour time at 0.10 second(s)/10 Hz measurement intervals with the Trimble R10 geodetic grade GNSS receiver.The original observation file was converted to RINEX format and then decimated into the different data sampling rates as 0.2 s,0.5 s,1 s,5 s,10 s,30 s,60 s,and 120 s.All these RINEX observation files were submitted to the Canadian Spatial Reference System-Precise Point Positioning(CSRS-PPP)online processing service the day after the data collection date by choosing both static and kinematic processing options.In this way,PPP-derived static coordinates,and the kinematic coordinates of each measurement epoch were calculated.The PPP-derived coordinates obtained from each decimated sampling intervals were compared to known coordinates of the GP for northing,easting,2D position,and height components.According to the static and kinematic processing results,high data sampling rates did not change the PPP solutions in terms of accuracy when compared to the results obtained using lower sampling rates.The results of this study imply that it was not necessary to collect GNSS data with high-rate intervals for many surveying projects requiring cm-level accuracy. 展开更多
关键词 Precise Point Positioning(PPP) online GNSS postprocessing service high-rate GNSS sampling rate monitoring structure behavior
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Internet and social media usage of orthopaedic patients:A questionnaire-based survey 被引量:1
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作者 Tahir Mutlu Duymus Hilmi Karadeniz +4 位作者 Mehmet Akif Cacan Baran Komür Abdullah Demirtas Sinan Zehir Ibrahim Azboy 《World Journal of Orthopedics》 2017年第2期178-186,共9页
AIM To evaluate social media usage of orthopaedic patients to search for solutions to their health problems. METHODS The study data were collected using face-to-face questionnaire with randomly selected 1890 patients ... AIM To evaluate social media usage of orthopaedic patients to search for solutions to their health problems. METHODS The study data were collected using face-to-face questionnaire with randomly selected 1890 patients aged over 18 years who had been admitted to the orthopaedic clinics in different cities and provinces across Turkey. The questionnaire consists of a total of 16 questions pertaining to internet and social media usage and demographics of patients, patients' choice of institution for treatment, patient complaints on admission, online hospital and physician ratings, communication between the patient and the physician and its effects.RESULTS It was found that 34.2%(n = 647) of the participants consulted with an orthopaedist using the internet and 48.7%(n = 315) of them preferred websites that allow users to ask questions to a physician. Of all questionaskers, 48.5%(n = 314) reported having found the answers helpful. Based on the educational level of the participants, there was a highly significant difference between the rates of asking questions to an orthopaedist using the internet(P = 0.001). The rate of questionasking was significantly lower in patients with an elementary education than that in those with secondary, high school and undergraduate education(P = 0.001) The rate of reporting that the answers given was helpful was significantly higher in participants with an undergraduate degree compared to those who were illiterate, those with primary, elementary or high school education(P = 0.001). It was also found that the usage of the internet for health problems was higher among managers-qualified participants than unemployed-housewives, officers, workers-intermediate staff(P < 0.05).CONCLUSION We concluded that patients have been increasingly using the internet and social media to select a specific physician or to seek solution to their health problems in an effective way. Even though the internet and social media offer beneficial effects for physicians or patients, there is still much obscurity reg 展开更多
关键词 PATIENT INTERNET Orthopedist Social media Communication
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Effects of Melatonin on Ischemia-Reperfusion Injury in Rat Ovary:Histopathologic and Immunohistochemical Study
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作者 Deniz Balsak Cihan Togrul +9 位作者 Cenap Ekinci Kerem Doga Seckin Mehmet Fatih Karsli Aysun Ekinci Ali Emre Tahaoglu Hanefi Bademkiran Zuat Acar Senem Yaman Tunc Engin Deveci Günsen Kirman 《Open Journal of Obstetrics and Gynecology》 2015年第11期639-645,共7页
Aim: To investigate the effect of melatonin on ischemia–reperfusion (I/R) injury in rat ovary. Material and Method: A total of 24 Wistar rats were divided into four groups. The rats were first numbered randomly and t... Aim: To investigate the effect of melatonin on ischemia–reperfusion (I/R) injury in rat ovary. Material and Method: A total of 24 Wistar rats were divided into four groups. The rats were first numbered randomly and then randomly divided into four equal groups: sham, torsion, detorsion and melatonin groups. In group I (n = 6) sham, as well as in group II ovary torsion was not performed and no drug was administered. In group III, 1 hour of ischemia and 2 hours of reperfusion were performed and no drug was given. In group IV, melatonin was dissolved in 1% ethanol just before use. Melatonin was injected 1 hour before torsion to the torsion plus melatonin group. Right ovaries were surgically removed in all groups. Result: Malondialdehyde (MDA) levels were measured. We suggested that administration of melatonin would be in treating ovaries from torsion/detorsion induced damage in humans. The histopathological changes such as vascular congestion, edema, hemorrhage, and follicular degeneration were found to be decreased in the melatonin + ischemia-reperfusion group. Ischemia-reperfusion group: PECAM-I expression is positive in vessel of the stromal area. The follicles and interfolicular area infiltrated with CD68 positive cells were increased in a time of ischemia-reperfusion exposure dependent manner. Conclusions: Melatonin after ischemia-reperfusion CD31 and CD68 expressions is weak, due to the reduction of the inflammatory effects and hemorrhage is thought that melatonin is effective. 展开更多
关键词 ISCHEMIA-REPERFUSION OVARY RAT CD31 CD68
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