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Refractory lipoatrophy treated with autologous whole blood injection:A case report
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作者 Wonnam Kim Jun Su Park En Hyung Kim 《World Journal of Clinical Cases》 SCIE 2025年第2期33-38,共6页
BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resol... BACKGROUND Intramuscular corticosteroid injection may cause adverse effects such as dermal and/or subcutaneous atrophy,alopecia,hypopigmentation,and hyperpigmentation.Although cutaneous atrophy can spontaneously resolve,several treatment options have been suggested for this condition.CASE SUMMARY In this paper,we report a case of corticosteroid injection induced lipoatrophy treated with autologous whole blood(AWB)injection,as the condition had been unresponsive to fractional laser therapy.A 29-year-old female patient visited the dermatology clinic complaining of skin depression on her right buttock area,which had appeared six months earlier.There had been only subtle improvement at the margins after fractional CO2 laser treatment;therefore,after obtaining informed consent from the patient,AWB treatment was initiated.One month after the first AWB injection,the size and depth of the lesion had noticeably improved,and a slight improvement was also observed in discoloration.CONCLUSION Close observation is the initial treatment of choice for steroid induced skin atrophy;however,for patients in need of immediate cosmetic improvement,AWB injection may be a safe and cost-effective alternative. 展开更多
关键词 ATROPHY CORTICOSTEROID Subcutaneous fat Autologous whole blood injection Laser therapy Case report
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Flow injection chemiluminescence determination of meloxicam using potassium permanganate and formaldehyde system 被引量:1
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作者 贾宝秀 曹明亮 +3 位作者 刘彩红 李玉琴 李珂 齐永秀 《Journal of Chinese Pharmaceutical Sciences》 CAS 2008年第1期35-40,共6页
A simple, rapid and sensitive flow injection chemiluminescence (FI-CL) method has been developed for the determination of meloxicam. The method is based on the CL-emitting reaction between meloxicam and potassium pe... A simple, rapid and sensitive flow injection chemiluminescence (FI-CL) method has been developed for the determination of meloxicam. The method is based on the CL-emitting reaction between meloxicam and potassium permanganate in a hydrochloric acid medium, enhanced by formaldehyde (HCHO). Under optimum conditions, calibration curve over the range of 1.0-20.0μg/mL was obtained. The proposed method was successfully applied to the determination of meloxicam in capsules with no evi- dence of interference from common excipients. The detection limit of this method was 25.6 ng/mL. The relative standard deviation was 2.1% for 10.0 μg/mL meloxicam. The sample throughput was found to be 120 samples/h. 展开更多
关键词 MELOXICAM flow injection chemiluminescence FORMALDEHYDE Pharmaceutical analysis
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Determination of Gossypol in Trace Level by Flow Injection Analysis with Chemiluminescence Detection 被引量:3
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作者 Bing Chun XUE Er Bao LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期57-60,共4页
This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitiz... This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10^-17-2.78×10^-16 mol/L in acid solution and 8.00×10^-11-7.39×10^-8mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×10^-18 mol/L (S/N=3). The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results. 展开更多
关键词 Single-molecule detection CHEMILUMINESCENCE flow injection gossypol.
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Determination of chlorogenic acid by flow injection irreversible biamperometry 被引量:3
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作者 Li Jun Li Qi Feng Chen +5 位作者 Lai Bo Yu Zhao Heng Zhong Jun Feng Hao Cheng Hong Xing Kong Jian Ling Wu 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第4期431-434,共4页
A flow injection irreversible biamperometric method for the determination of chlorogenic acid is described. The proposed method is based on the electrochemical oxidation of chlorogenic acid at pretreated platinum elec... A flow injection irreversible biamperometric method for the determination of chlorogenic acid is described. The proposed method is based on the electrochemical oxidation of chlorogenic acid at pretreated platinum electrode and the reduction of permanganate at another electrode to form an irreversible biamperometric detection system. Under the external potential difference (z^v) of 0 V, in the 0.05 mol/L sulfuric acid, chlorogenic acid can be determined over the range 0.8-120 mg/L with a sample measurement frequency of 80 samples/h. The detection limit is 0.18 mg/L. The proposed method exhibits the satisfactory reproducibility with a relative standard derivation (R.S.D.) of 2.21% for 19 successive determinations of 40 mg/L. 展开更多
关键词 flow injection Irreversible biamperometry Chlorogenic acid HONEYSUCKLE
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The Determination of Iodide Based on a Flow-injection Coupling Irreversible Biamperometry 被引量:3
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作者 Li Jun LI Hao CHENG +5 位作者 Wen Yi HUANG Hong Xing KONG Jian Ling WU Jian Ping LU Wei GAO Jun Feng SONG 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第12期1629-1632,共4页
A novel flow-injection irreversible biamperometric method is described for the direct determination of iodide. The method is based on electrochemical oxidation of iodide at the gold electrode and the reduction of perm... A novel flow-injection irreversible biamperometric method is described for the direct determination of iodide. The method is based on electrochemical oxidation of iodide at the gold electrode and the reduction of permanganate at the platinum electrode to form an irreversible biamperometric detection system. Under the applied potential difference of 0 V, in the 0.05 mol/L sulfuric acid, iodidecan be determined over the range 4.00×10^-7-1.00×10^-5 mol/L with a sampling frequency of 120 samples per hour. The detection limit for I- is 3.0×10^-7 mol/L and the RSD for 40 replicate determinations of 4.0×10^-5 mol/L potassium iodide is 1.68%. The new method was applied to the analysis of iodide in table salt with satisfactory results. 展开更多
关键词 IODIDE flow injection irreversible biamperometry gold electrode platinum electrode
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Protective effect of Danhong injection in patients with acute myocardial infarction at a high risk of no-reflow during primary percutaneous coronary intervention 被引量:18
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作者 Qi YOU Jing WANG +4 位作者 Wei DONG Feng TIAN Hong-Xu LIU Jing JING Yun-Dai CHEN 《Journal of Geriatric Cardiology》 SCIE CAS CSCD 2019年第5期406-413,共8页
Objective To observe the effect of Danhong injection(DI)in patients with acute ST-segment elevation myocardial infarction(STEMI)at a high risk of no-reflow(NR)during primary percutaneous coronary intervention(PCI).Met... Objective To observe the effect of Danhong injection(DI)in patients with acute ST-segment elevation myocardial infarction(STEMI)at a high risk of no-reflow(NR)during primary percutaneous coronary intervention(PCI).Methods Patients were placed in a DI group and control group.The DI group was given DI and the control group was given physiologic saline.The administration lasted 4 to 6 days in both groups after PCI.Cardiac magnetic resonance(CMR)was carried out during the perioperative period(7±2 days).The primary endpoint of the study was myocardial infarct size(IS)imaged on delayed-enhancement CMR.The secondary endpoint was major adverse cardiac events observed 6 months after PCI.Results In total,160 high-risk NR patients were enrolled,and 110 patients completed the CMR examination.According to postoperative CMR,the Myocardial Salvage Index and left ventricular ejection fraction were higher in the DI group(0.57±0.13 vs.0.48±0.17,P<0.01;49.3%±6.9%vs.46.2%±7.7%,P=0.03,respectively),whereas the IS was lower(19.7%±5.6%vs.22.2%±6.5%,P=0.04),compared with that in the control group.These differences were observed to be significant.After 6 months,the prevalence of major adverse cardiac events in the DI group decreased compared with that in the control group,but the differences were not observed to be significant(P>0.05).Conclusion The application of DI can reduce the myocardial infarct size in STEMI patients at a high risk of NR during primary PCI. 展开更多
关键词 Cardiac magnetic resonance DANHONG injection MYOCARDIAL INFARCTION NO-REflow risk
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Flow injection spectrophotometric determination of vitamin E in pharmaceuticals,milk powder and blood serum using potassium ferricyanide-Fe(Ⅲ) detection system 被引量:3
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作者 Saima Jadoon Amir Waseem +1 位作者 Mohammad Yaqoob Abdul Nabi 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第6期712-715,共4页
A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection system.In the presence of vitamin E,Fe(Ⅲ)/ferricyanide redu... A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection system.In the presence of vitamin E,Fe(Ⅲ)/ferricyanide reduces.The in situ reduced ions are then reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to make soluble Prussian blue,which is monitored at absorption wavelength of 735 nm.Linear calibration graph was obtained in the concentration range of 0.1-40μg mL^(-1).The relative standard deviations (n=4) were in the range of 1.1-3.6%,with limits of detection(3 s blank) of 0.04μg mL^(-1).The proposed method allowed 12 injections h^(-1).The method is applied to determine vitamin E in pharmaceuticals,infant milk and blood serum samples using hexane extraction with the recoveries in the range of 93±3 to 97.5±4%.The method is validated using certified reference materials SRM 968c for blood serum samples. 展开更多
关键词 flow injection SPECTROPHOTOMETRY Vitamin E Prussian blue FE(III) FERRICYANIDE Pharmaceuticals Blood serum
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A Probabilistic Trust Model and Control Algorithm to Protect 6G Networks against Malicious Data Injection Attacks in Edge Computing Environments 被引量:1
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作者 Borja Bordel Sánchez Ramón Alcarria Tomás Robles 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第10期631-654,共24页
Future 6G communications are envisioned to enable a large catalogue of pioneering applications.These will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control l... Future 6G communications are envisioned to enable a large catalogue of pioneering applications.These will range from networked Cyber-Physical Systems to edge computing devices,establishing real-time feedback control loops critical for managing Industry 5.0 deployments,digital agriculture systems,and essential infrastructures.The provision of extensive machine-type communications through 6G will render many of these innovative systems autonomous and unsupervised.While full automation will enhance industrial efficiency significantly,it concurrently introduces new cyber risks and vulnerabilities.In particular,unattended systems are highly susceptible to trust issues:malicious nodes and false information can be easily introduced into control loops.Additionally,Denialof-Service attacks can be executed by inundating the network with valueless noise.Current anomaly detection schemes require the entire transformation of the control software to integrate new steps and can only mitigate anomalies that conform to predefined mathematical models.Solutions based on an exhaustive data collection to detect anomalies are precise but extremely slow.Standard models,with their limited understanding of mobile networks,can achieve precision rates no higher than 75%.Therefore,more general and transversal protection mechanisms are needed to detect malicious behaviors transparently.This paper introduces a probabilistic trust model and control algorithm designed to address this gap.The model determines the probability of any node to be trustworthy.Communication channels are pruned for those nodes whose probability is below a given threshold.The trust control algorithmcomprises three primary phases,which feed themodel with three different probabilities,which are weighted and combined.Initially,anomalous nodes are identified using Gaussian mixture models and clustering technologies.Next,traffic patterns are studied using digital Bessel functions and the functional scalar product.Finally,the information coherence and content are analyzed.The noise content and abnormal information sequences are detected using a Volterra filter and a bank of Finite Impulse Response filters.An experimental validation based on simulation tools and environments was carried out.Results show the proposed solution can successfully detect up to 92%of malicious data injection attacks. 展开更多
关键词 6G networks noise injection attacks Gaussian mixture model Bessel function traffic filter Volterra filter
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Study on Chemiluminescence Reactions of L ucigenin and Reductants by Flow Injection Analysis 被引量:1
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作者 Zhi Jia ZHU Jiu Ru LU (Experimental Center, Hebei Normal University. Shijiazhuang 050016 Department of Chemistry, Shaanxi Normal University, Xian 710062) 《Chinese Chemical Letters》 SCIE CAS CSCD 2000年第1期61-64,共4页
The chemiluminescence reactions between lucigenin and reductants such as Mo(LII),V( II), U(III), W(III), Cr(II), Ti(III) and Fe( II), which were produced on-line by passing Mo(VI),V(V),U(VI), W(VI), Cr(VI,III),Ti(IV) ... The chemiluminescence reactions between lucigenin and reductants such as Mo(LII),V( II), U(III), W(III), Cr(II), Ti(III) and Fe( II), which were produced on-line by passing Mo(VI),V(V),U(VI), W(VI), Cr(VI,III),Ti(IV) and Fe(III) through a micro Jones column, are studied in detail. Results show that the reactions can be used directly for the determination of these substances. The mechanism of the reactions is also investigated. 展开更多
关键词 reductant LUCIGENIN CHEMILUMINESCENCE flow injection analysis
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Reversed flow injection spectrophotometric determination of low residuals of chlorine dioxide in water using chlorophenol red 被引量:1
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作者 WangGZ ChenH 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2002年第3期423-427,共5页
A novel, simple, rapid, sensitive and highly selective flow injection procedure for the spectrophotometric determination of chlorine dioxide in the presence of other chlorine species, viz,free chlorine, chlorite, chlo... A novel, simple, rapid, sensitive and highly selective flow injection procedure for the spectrophotometric determination of chlorine dioxide in the presence of other chlorine species, viz,free chlorine, chlorite, chlorate and hypochlorite, is developed. The method is based on the discoloration reaction between chlorine dioxide and chlorophenol red and can overcome the shortcomings existed in direct spectrophotometric determination for chlorine dioxide owing to the serious interference of free and combined chlorine. The procedure gave a linear calibration graph over the range 0—0.71 mg/L of chlorine dioxide. With a detection limit of 0.024 mg/L and a sample throughput of 60 samples/h. 展开更多
关键词 chlorine dioxide chlorophenol red reversed flow injection SPECTROPHOTOMETRY
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Flow-injection Determination of Cysteine,N-Acetyl Cysteine and Glutathione in Pharmaceuticals via Potassium Ferricyanide-Fe(Ⅲ) Spectrophotometric System 被引量:1
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作者 WASEEM Amir YAQOOB Mohammad NABI Abdul 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第6期893-898,共6页
A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted wi... A simple flow injection spectrophotometric method is reported for the determination of cysteine,N-acetyl cysteine and glutathione based on the reduction of Fe(Ⅲ)/ferricyanide,the in situ reduced ions are reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to form soluble Prussian blue,which is monitored at 735 nm.The calibration graphs are linear in the concentration ranges of(1―100)×10-6 mol/L for cysteine and N-acetyl cysteine,and(1―50)×10-6 mol/L for glutathione.The relative standard deviations of 1.8%,2.5% and 1.9% were found for eleven replicate analyses of 5×10-6 mol/L cysteine,N-acetyl cysteine and glutathione.The limits of detection(3σ blank) at 5×10-7 mol/L for cysteine,and 3×10-7 mol/L for N-acetyl cysteine and glutathione were obtained.The proposed method allowed 60 injections/h.The effects of common substances present in pharmaceuticals and human physiological fluids were examined.The method was applied to determining cysteine in pharmaceutical formulations with the recoveries in a range of 97% to 106% and the results obtained are agreed well with labeled values. 展开更多
关键词 flow injection SPECTROPHOTOMETRY CYSTEINE Prussian blue Fe(Ⅲ) FERRICYANIDE PHARMACEUTICAL
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Flow Injection Chemiluminescence Analysis of Low Level Concentration of Hydrazine 被引量:1
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作者 Zheng Hua SONG Lin WANG +1 位作者 Ji Hong Lü Tie Zhu ZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第9期799-802,共4页
Combined with flow-injection (FI) technology, a simple chemiluminescence (CL) method was developed for hydrazine determination in this paper. It was found that hydrazine could greatly decrease the strong CL signal pro... Combined with flow-injection (FI) technology, a simple chemiluminescence (CL) method was developed for hydrazine determination in this paper. It was found that hydrazine could greatly decrease the strong CL signal produced by the reaction between luminol and hexacyanoferrate (III) in alkaline medium. The decreased CL intensity was linear with hydrazine concentration in the range of 5.0×10-9 g·mL-1 to 4.0×10-5 g·mL-1, and the limit of detection was 2.0×10-9 g·mL-1 (3σ) with a relative standard deviation of 2.4~4.1% (n=5). 展开更多
关键词 HYDRAZINE flow injection CHEMILUMINESCENCE
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Reagent-free determination of amikacin content in amikacin sulfate injections by FTIR derivative spectroscopy in a continuous flow system 被引量:1
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作者 José F.Ovalles Máximo Gallignani +2 位作者 María R.Brunetto Rebeca A.Rondón Carlos Ayala 《Journal of Pharmaceutical Analysis》 SCIE CAS 2014年第2期125-131,共7页
The quantitative estimation of amikacin (AMK) in AMK sulfate injection samples is reported using FTIR-derivative spectrometric method in a continuous flow system. Fourier transform of mid-IR spectra were recorded wi... The quantitative estimation of amikacin (AMK) in AMK sulfate injection samples is reported using FTIR-derivative spectrometric method in a continuous flow system. Fourier transform of mid-IR spectra were recorded without any sample pretreatment. A good linear calibration (r40.999, %RSDo 2.0) in the range of 7.7-77.0 mg/mL was found. The results showed a good correlation with the manufacturer's and overall they all fell within acceptable limits of most pharmacopoeial monographs on AMK sulfate. 展开更多
关键词 AMIKACIN FlrIR derivative spectro-metry Continuous flow system Pharmaceuticalpreparation injection SULFATE
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Flow-injection Spectrophotometric Determination of Uric Acid in Urine via Prussian Blue Reaction 被引量:1
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作者 WASEEM Amir YAQOOB Mohammad +2 位作者 NABI Abdul MURTAZA Ghulam HUSSAIN Izhar 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第6期929-933,共5页
A simple and sensitive flow injection(FI) spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe(III)/ferricyanide in the presence of uric acid. The in situ reduced ... A simple and sensitive flow injection(FI) spectrophotometric method was reported for the determination of uric acid based on the reduction of Fe(III)/ferricyanide in the presence of uric acid. The in situ reduced ions reacted with unreduced portion of ferricyanide/Fe(III) to form soluble Prussian blue, which was monitored at an absorption wavelength of 735 nm. The optimized conditions allow a linear calibration graph in a concentration range of 1―100 μmol/L. The relative standard deviation was in a range of 0.5%―2.5%, with a detection limit(3σ blank) of 0.3 μmol/L and a sampling frequency of 60 injection/h was obtained. The effect of common substances present in human physiological fluids on the determination of uric acid was examined. The method was applied to determining uric acid in human urine samples with the recoveries in a range of 96%―105%. The results agree well with those by spectrophotometric reference method at a confidence level of 95%. Spectrophotometric procedures for uric acid determination in clinical samples were reviewed briefly. 展开更多
关键词 flow injection analysis SPECTROPHOTOMETRY Uric acid Prussian blue URINE
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Determination of Ciprofloxacin by Flow Injection Analysis Based on Chemiluminescence System 被引量:1
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作者 张卓勇 李夏 +3 位作者 王小丽 陈世稆 宋保华 赵慧春 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第3期285-288,共4页
A novel flow injection chemiluminescence (CL) method for the determination of ciprofloxacin (CPLX) was reported. The proposed method is based on luminescence produced by KMnO4-Na2S2O4-Tb^3+-CPLX chemiluminescence... A novel flow injection chemiluminescence (CL) method for the determination of ciprofloxacin (CPLX) was reported. The proposed method is based on luminescence produced by KMnO4-Na2S2O4-Tb^3+-CPLX chemiluminescence (CL) system. The effects of some critical experimental conditions were discussed and the optimization of working conditions was investigated. The linear dynamic range is 3.00 × 10^-8 - 9.00 × 10^-7 mol ·L-1 and the detection limit for CPLX is 4.40 × 10^-9 mol·L^-1. This method was applied to the determination of CPLX in tablet, urine, and serum samples and the recoveries of real sample analyses were in the range from 110 ± 4 to 104 ± 4. 展开更多
关键词 CIPROFLOXACIN CHEMILUMINESCENCE TERBIUM flow injection KMNO4 Na2S2O4 rare earths
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A Clinical Study of Safflower Yellow Injection in Treating Coronary Heart Disease Angina Pectoris with Xin-Blood Stagnation Syndrome 被引量:12
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作者 张琼 彭建华 张向农 《Chinese Journal of Integrated Traditional and Western Medicine》 2005年第3期222-225,共4页
Objective: To evaluate the clinical effect and safety of Safflower Yellow injection (SYI) in treating coronary heart disease angina pectoris (OHD-AP) with Xin-blood stagnation syndrome (XBSS). Methods: Adopted... Objective: To evaluate the clinical effect and safety of Safflower Yellow injection (SYI) in treating coronary heart disease angina pectoris (OHD-AP) with Xin-blood stagnation syndrome (XBSS). Methods: Adopted was the multi-centered, randomized, positive parallel controlled method, 448 patients with CHD-AP-XBSS were enrolled and divided into two groups, 336 in the tested group treated with SYI and 112 in the control group treated with Salvia injection by intravenous dripping once a day for 14 days, so as to observe the conditions of angina, electrocardiogram, and therapeutic effect on traditinal Chinese medicine (TCM) symptoms as well as the safety of the treatment. Results: The significantly effective rate and total effective rate in the tested group were 60.06% (194/323) and 91.02 % (294/323) respectively; those in improvement of TOM symptoms were 40. 18% (129/321) and 75.23% (243/323) respectively, which were better than those in the control group (P〈0.01). Conclusion: SYI Injection is effective and safe in treating OHD-AP-XBSS. 展开更多
关键词 Safflower yellow injection coronary heart disease angina pectoris Xin-Blood stagnation syndrome
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A Novel Flow Injection Optical Fiber Biosensor for Hypoxanthine Based on Luminol Electrochemiluminescence 被引量:1
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作者 LI Ying xiu ZHU Lian de ZHU Guo yi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第2期240-244,共5页
关键词 ELECTROCHEMILUMINESCENCE flow injection Optical fiber biosensor Sol-gel Ceramic-carbon composite electrode HYPOXANTHINE Fish freshness
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Determination of Trace Non Rare Earth Elements in High Purity Rare Earth Oxides by ICP-AES with Microcolumn Preconcentration in a Flow Injection System 被引量:1
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作者 吉红念 廖振环 +1 位作者 江祖成 谢金娥 《Journal of Rare Earths》 SCIE EI CAS CSCD 1995年第2期119-124,共6页
A new method for the determination of trace non-rare earth elements in high purity rare earth oxides by ICP-AES with preconcentration on an active carbon-silica gel microcolumn in a flow injection system is described ... A new method for the determination of trace non-rare earth elements in high purity rare earth oxides by ICP-AES with preconcentration on an active carbon-silica gel microcolumn in a flow injection system is described in this paper. Experimental parameters such as pH, flow rate,reagent concentration,length of reaction coil,eluent acidity,etc. were optimized. In the buffer solution of NH3. H2O/NH4Cl at pH 4. 6,Al,Cr,Cu,Fe, Pb, V and Zn can be preconcentrated and then eluted with 4. 5 mol/L nitric acid utilizing stop-flow technique. The enrichment factors were in range of 8. 1 ̄12. 6 with detection limits of μg/m level ,and the RSD with metals at μg/g level were 2. 3 ̄5. 0% (n= 7). The method proposed can reduce the matrix interference effectively , and has been applied to the determination of non-rare earth metals atμg/g level in high purity Eu2O3 with satisfactory results. 展开更多
关键词 flow injection ICP-AES Active carbon-silica gel Sodium diethyldithiocarbamate Stop-flow technique Microcolumn preconcentration High purity Eu_2O_3
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TWO-PHASE FLOW FOR A HORIZONTAL WELL PENETRATING A NATURALLY FRACTURED RESERVOIR WITH EDGE WATER INJECTION 被引量:1
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作者 郭大立 刘慈群 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1995年第5期937-942,共6页
This paper examines the two-phase flow for a horizontal well penetrating a naturally fractured reservoir with edge water injection by means of a fixed streamlinemodel,The mathematical model of the verical two-dimensio... This paper examines the two-phase flow for a horizontal well penetrating a naturally fractured reservoir with edge water injection by means of a fixed streamlinemodel,The mathematical model of the verical two-dimensional flow or oil-water for a horizontal well in a medium with double-porosity is established ,and whose accuratesolutions are obtained by using the characteristic method .The saturation distributionsin the fractured system and the matrix system as well as the formula of the time of water free production are presented .All these results provide a theoretical basis and a computing method for oil displacement by edge water from naturally fracturedreservirs. 展开更多
关键词 horizontal well two-phase flow medium with double-porosityedge water injection characteristic method
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On-line Preconcentration and Determination of Trace Metals in Water Samples by Flow Injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column 被引量:1
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作者 GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong College of Chemistry, Jilin University, Changchun 130012, P. R. China 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2012年第1期26-30,共5页
An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection(FI) micro-column preconcentration coupled with flame atomic absorption spectrometry(FAAS) determinatio... An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection(FI) micro-column preconcentration coupled with flame atomic absorption spectrometry(FAAS) determination of trace heavy metals(Cu, Pb, Co, Ni and Cd). Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations(RSDs) were less than 2.76%(n=7). Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples. 展开更多
关键词 arene carboxylic acid PRECONCENTRATION flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)
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