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Si对SiC-Al系统浸润行为的影响 被引量:19
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作者 张永俐 米..,dl 《材料科学与工程》 CSCD 1994年第2期16-23,共8页
用液滴技术(The Sessile Drop Technique)、SEM、EDS等研究了Si对SiC-Al系统浸润行为的影响,结果表明,在较低温度下,Si在熔融Al合金中的含量不明显影响Al对SiC的浸润行为,然而... 用液滴技术(The Sessile Drop Technique)、SEM、EDS等研究了Si对SiC-Al系统浸润行为的影响,结果表明,在较低温度下,Si在熔融Al合金中的含量不明显影响Al对SiC的浸润行为,然而,在高温下SiC和Al的接触角θ值随时间而减小的速率随Si含量的增加而增大;SiC-Al系统从非浸润到浸润的转变温度随Si含量的增加而降低;Si的添加引起Al合金在SiC表面扩展和向SiC基体渗透,而且扩展和渗透的程度随Si含量增加而增大。说明在Al合金中添加Si可促进对SiC的浸润。本研究还证实了基体参加反应可增强金属Al对SiC陶瓷的浸润能力。 展开更多
关键词 浸润 金属复合材料 碳化硅
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输卵管妊娠:诊断与治疗现况 被引量:23
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作者 Fyls.,dl 《世界医学杂志》 1999年第2期68-74,共7页
关键词 输卵管妊娠 诊断 治疗
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FADD and TRADD expression and apoptosis in primary hepatocellular carcinoma 被引量:22
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作者 Sun BH Zhao XP +2 位作者 Wang BJ Yang dl Hao LJ 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第2期223-227,共5页
AIM To investigate the clinical features ofFADD and TRADD expressions in primaryhepatocellular carcinoma(HCC)and todetermine their relationship with hepaticapoptosis.METHODS FADD and TRADD expressions weredetected by ... AIM To investigate the clinical features ofFADD and TRADD expressions in primaryhepatocellular carcinoma(HCC)and todetermine their relationship with hepaticapoptosis.METHODS FADD and TRADD expressions weredetected by immunohistochemistry and hepaticapoptosis were determined by in situ end-labeling(ISEL).RESULTS Ten(25.6%)cases of HCC weredetected to express FADD protein.The positiverate in HCC is lower than that in non-cancerousadjacent liver tissues(62.5%)(P【0.05).Inthose of grade Ⅰ-Ⅱ,8(38.1%)cases wereFADD positive,while only 2/18(11.1%)casesof grade Ⅲ-Ⅳ had detectable FADD protein(P【0.05).No relationship was found betweenFADD expression and other clinical features,such as gender,age,tumor size,differentiationor metastasis.ISEL positive cells can be seen inall cases of HCC.The hepatic apoptosis wasassociated with FADD expression as moreapoptotic cells were detected in those caseswhich had moderately to strongly positiveFADD,as compared with negative or weakpositive FADD cases(P【0.05).No relationshipwas found between FADD expression and hepaticapoptosis in non-cancerous adjacent livertissues.Fifteen of 39(38.5%)cases of HCCwere found positive for TRADD protein,andsimilar positive rate(37.5%)in non-cancerousadjacent liver tissues(P】0.05).The expressionof TRADD is correlated with HCC differentiation, as only 22.2% of moderately to highlydifferentiated HCC showed positive TRADDprotein,while as high as 52.4% of poorlydifferentiated HCC had TRADD(P【0.05),Norelationship was found between TRADDexpression and gender,age,tumor size or gradeor metastasis,although 42.9% of HCC of gradeⅠ/Ⅱ showed positive TRADD which wasslightly higher than that of grade Ⅲ/Ⅳ(33.3%,P】0.05).Hepatic apoptosis was not related toTRADD expression in HCC or non-cancerousadjacent liver tissues.CONCLUSION Loss of FADD expression playsan important role in HCC carcinogenesis,andexpression of TRADD also contributes to HCCdevelopment.The cell apoptosis in HCC isassociated with FADD expression.However,theexpression of TR 展开更多
关键词 FADD TRADD APOPTOSIS CARCINOMA HEPATOCELLULAR liver NEOPLASMS
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牛蒡子中血小板活化因子(PAF)受体拮抗剂的分离和结构鉴定 被引量:12
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作者 韩桂秋 白光清 +3 位作者 王夕红 Liesch JM Zink dl Hwang SB 《中草药》 CAS CSCD 北大核心 1992年第11期563-566,共4页
关键词 牛蒡子 PAF 皂甙
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Epidermal growth factor prevents gut atrophy and maintains intestinal integrity in rats with acute pancreatitis 被引量:10
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作者 Chen dl Wang WZ Wang JY 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期762-765,共4页
INTRODUCTIONThere is abundant evidence that stressful insults suchas acute pancreatitis may significantly alter themetabolism of the gut mucosa and therefore itsbarrier integrity,resulting in an increase in mucosalper... INTRODUCTIONThere is abundant evidence that stressful insults suchas acute pancreatitis may significantly alter themetabolism of the gut mucosa and therefore itsbarrier integrity,resulting in an increase in mucosalpermeability and subsequent translocation of entericbacteria and their cndotoxins.The fact thatmost bacteria associated with acute pancreatic andperipancreatic infections are of enteric originimplies that the gut plays a major role in 展开更多
关键词 PANCREATITIS EPIDERMAL growth factor PARENTERAL nutrition total INTESTINAL MUCOSA DNA proteins
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Artificial intelligence in the diagnosis and management of colorectal cancer liver metastases 被引量:9
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作者 Gianluca Rompianesi Francesca Pegoraro +2 位作者 Carlo dl Ceresa Roberto Montalti Roberto Ivan Troisi 《World Journal of Gastroenterology》 SCIE CAS 2022年第1期108-122,共15页
Colorectal cancer(CRC)is the third most common malignancy worldwide,with approximately 50%of patients developing colorectal cancer liver metastasis(CRLM)during the follow-up period.Management of CRLM is best achieved ... Colorectal cancer(CRC)is the third most common malignancy worldwide,with approximately 50%of patients developing colorectal cancer liver metastasis(CRLM)during the follow-up period.Management of CRLM is best achieved via a multidisciplinary approach and the diagnostic and therapeutic decision-making process is complex.In order to optimize patients’survival and quality of life,there are several unsolved challenges which must be overcome.These primarily include a timely diagnosis and the identification of reliable prognostic factors.Furthermore,to allow optimal treatment options,a precision-medicine,personalized approach is required.The widespread digitalization of healthcare generates a vast amount of data and together with accessible high-performance computing,artificial intelligence(AI)technologies can be applied.By increasing diagnostic accuracy,reducing timings and costs,the application of AI could help mitigate the current shortcomings in CRLM management.In this review we explore the available evidence of the possible role of AI in all phases of the CRLM natural history.Radiomics analysis and convolutional neural networks(CNN)which combine computed tomography(CT)images with clinical data have been developed to predict CRLM development in CRC patients.AI models have also proven themselves to perform similarly or better than expert radiologists in detecting CRLM on CT and magnetic resonance scans or identifying them from the noninvasive analysis of patients’exhaled air.The application of AI and machine learning(ML)in diagnosing CRLM has also been extended to histopathological examination in order to rapidly and accurately identify CRLM tissue and its different histopathological growth patterns.ML and CNN have shown good accuracy in predicting response to chemotherapy,early local tumor progression after ablation treatment,and patient survival after surgical treatment or chemotherapy.Despite the initial enthusiasm and the accumulating evidence,AI technologies’role in healthcare and CRLM management is not ye 展开更多
关键词 Colorectal cancer Liver metastases Artificial intelligence Machine learning Deep learning Neural networks Radiomics
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再分析方法用于精神病学研究 被引量:9
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作者 Streiner dl 陈向一 《国外医学(精神病学分册)》 1992年第1期20-23,共4页
再分析方法是一种对许多研究进行归纳总结的较为客观的技术,可从各研究结果中得出总的结论。本文介绍了再分析的两种基本方法,并就具体实施中必须注意的有关问題进行了讨论。
关键词 再分析 精神病
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临床应用氯胺酮25年后的看法 被引量:9
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作者 Relch dl Silvay G 胡兴国 《国外医学(麻醉学与复苏分册)》 北大核心 1991年第4期203-206,共4页
一、药理学 (一)药物动力学:静注或肌注氯胺酮后的生物利用度高。口服或直肠给氯胺酮,因首过效应和吸收少,所以需用较大剂量。氯胺酮在肝脏生物转化成多种代谢产物。通过细胞色素P450,经N-脱甲基形成去甲氯胺酮(Norketamine)。
关键词 氯胺酮 药理学 临床
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Current progress in use of adipose derived stem cells in peripheral nerve regeneration 被引量:8
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作者 Shomari dl Zack-Williams Peter E Butler Deepak M Kalaskar 《World Journal of Stem Cells》 SCIE CAS 2015年第1期51-64,共14页
Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modula... Unlike central nervous system neurons; those in the peripheral nervous system have the potential for full regeneration after injury. Following injury, recovery is controlled by schwann cells which replicate and modulate the subsequent immune response. The level of nerve recovery is strongly linked to the severity of the initial injury despite the significant advancements in imaging and surgical techniques. Multiple experimental model shave been used with varying successes to augment the natural regenerative processes which occur following nerve injury. Stem cell therapy in peripheral nerve injury may be an important future intervention to improve the best attainable clinical results. In particular adipose derived stem cells(ADSCs) are multipotent mesenchymal stem cells similar to bone marrow derived stem cells, which are thought to have neurotrophic properties and the ability to differentiate into multiple lineages. They are ubiquitous within adipose tissue; they can form many structures resembling the mature adult peripheral nervous system. Following early in vitro work; multiple small and large animal in vivo models have been used in conjunction with conduits, autografts and allografts to successfully bridge the peripheral nerve gap. Some of the ADSC related neuroprotective and regenerative properties have been elucidated however much work remains before a model can be used successfully in human peripheral nerve injury(PNI). This review aims to provide a detailed overview of progress made in the use of ADSC in PNI, with discussion on the role of a tissue engineered approach for PNI repair. 展开更多
关键词 PERIPHERAL NERVE INJURY ADIPOSE derivedstem CELLS Cell based THERAPIES Stem CELLS
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缺血性脑卒中患者血压与住院临床结局的相关性 被引量:7
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作者 Bangalore S Schwamm L +8 位作者 Smith EE Hellkamp AS Suter RE Xian Y Schulte PJ Fonarow GC Bhatt dl 练桂丽 叶鹏 《中华高血压杂志》 CAS CSCD 北大核心 2017年第11期1081-1083,共3页
高血压是脑卒中的主要危险因素。研究表明,在缺血性脑卒中患者中,由于压力依赖性的脑血液流向缺血区域,脑卒中后高血压有益。然而,其他研究显示,脑卒中后的高血压与短期再发性脑卒中、脑出血性转化和脑水肿发生率升高有关。关于血... 高血压是脑卒中的主要危险因素。研究表明,在缺血性脑卒中患者中,由于压力依赖性的脑血液流向缺血区域,脑卒中后高血压有益。然而,其他研究显示,脑卒中后的高血压与短期再发性脑卒中、脑出血性转化和脑水肿发生率升高有关。关于血压与脑卒中短期临床结局相关性的观察性研究结论相互矛盾。此外,关于血压的搏动组分(脉压)或稳定组分(平均动脉压)与临床结局相关性的数据有限。 展开更多
关键词 卒中后高血压 脑卒中患者 临床结局 相关性 缺血性 平均动脉压 住院 再发性脑卒中
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颈动脉内膜切除治疗暂时性脑缺血 被引量:7
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作者 周定标 Eric.,dl 《中华外科杂志》 CAS CSCD 北大核心 1989年第12期743-745,共3页
关键词 暂时性脑缺血 动脉内膜切除 TIA
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A Whitecap Coverage Model Based on the Surface Slope For Criterion of Wave Breaking 被引量:4
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作者 Xu, dl Yu, DY Lu, HM 《China Ocean Engineering》 SCIE EI 1998年第1期73-85,共13页
Using the limit surface slope as a criterion of wave breaking, a simple model for estimating the spatial fraction of breaking surface of sea at an instant, which is regarded as the whitecap coverge in this paper, is a... Using the limit surface slope as a criterion of wave breaking, a simple model for estimating the spatial fraction of breaking surface of sea at an instant, which is regarded as the whitecap coverge in this paper, is analytically derived from the probability density of surface slope based on Gaussian statistics. The resulting fraction is found depending on the fourth moment of wave spectum, m(4), as well as the critical threshold of surface slope. By expressing the fourth moment in terms of the Neumann spectrum, a formula linking the fraction and wind speed for fully developed sea states is obtianed. Another formula relating the fraction to both wind speed and fetch (or duration) is achieved by expressing m, in terms of the Krylov spectrum and applying the empirical relationships used in the SMB ocean wave predicting technique. A comparison between these results and the field data of whitecap coverage collected by Monahan and O'Muircheartuigh shows an encouraging agreement. 展开更多
关键词 whitecap coverage criterion of wave breaking wind speed wind fetch wind duration fully developed sea state fetch-limited sea state
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Joint Distribution of Wave Heights and Wavelengths and Distribution of Wave Steepness 被引量:5
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作者 Zheng, GZ Liu, XH Xu, dl 《China Ocean Engineering》 SCIE EI 1999年第2期145-154,共10页
A joint probability density is derived for wavelengths and wave heights. It is asymmetric and depends only on the spectral bandwidth epsilon defined by Cartwright and Longuet-Higgins (1956). After that a theoretical p... A joint probability density is derived for wavelengths and wave heights. It is asymmetric and depends only on the spectral bandwidth epsilon defined by Cartwright and Longuet-Higgins (1956). After that a theoretical probability density for wave steepness is obtained. It tends to Rayleigh distribution as epsilon --> 0. A comparison between theoretical steepness distribution and laboratory experiment result shows good agreement. 展开更多
关键词 wave height WAVELENGTH wave steepness probability density
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缺血再灌流损伤──危重病基础及临床研究新领域(上) 被引量:4
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作者 蒋健 Fang Xiao Carden dl 《急诊医学》 CSCD 1997年第5期310-313,共4页
关键词 危重病 缺血再灌注损伤
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玻璃装饰用无铅色料 被引量:5
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作者 Stan.,dl 王芙蓉 《国外建材译丛》 1994年第1期41-43,46,共4页
关键词 玻璃 装饰 无铅色料 釉彩
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Increased catabolism and decreased unsaturation of ganglioside in patients with inflammatory bowel disease 被引量:4
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作者 John J Miklavcic Glen K Shoemaker +8 位作者 Vera C Mazurak M Tom Clandinin Tasha dl Hart Kareena L Schnabl Gordon M Lees Bodil MK Larsen Oliver F Bathe Alan BR Thomson M Tom Clandinin 《World Journal of Gastroenterology》 SCIE CAS 2015年第35期10080-10090,共11页
AIM: To investigate whether accelerated catabolism of ganglioside and decreased ganglioside content contribute to the etiology of pro-inflammatory intestinal disease. METHODS: Intestinal mucosa from terminal ileum or ... AIM: To investigate whether accelerated catabolism of ganglioside and decreased ganglioside content contribute to the etiology of pro-inflammatory intestinal disease. METHODS: Intestinal mucosa from terminal ileum or colon was obtained from patients with ulcerative colitis or inflammatory Crohn's disease(n = 11) undergoing bowel resection and compared to control samples of normal intestine from patients with benign colon polyps(n = 6) and colorectal cancer(n = 12) in this observational case-control study. Gangliosides and phospholipids of intestinal mucosa were characterized by class and ceramide or fatty acid composition using liquid chromatography triple-quad mass spectrometry. Content and composition of ganglioside classes GM1, GM3, GD3, GD1 a, GT1 and GT3 were compared among subject groups. Content and composition of phospholipid classes phosphatidylcholine(PC) and phosphatidylethanolamine were compared among subject groups. Unsaturation index of individual ganglioside and phospholipid classes was computed and compared among subject groups. Ganglioside catabolism enzymes beta-hexosaminidase A(HEXA) and sialidase-3(NEU3) were measured in intestinal mucosa using western blot and compared among subject groups. RESULTS: Relative GM3 ganglioside content was 2-fold higher(P < 0.05) in intestine from patients with inflammatory bowel disease(IBD) compared to control intestine. The quantity of GM3 and ratio of GM3/GD3 was also higher in IBD intestine than control tissue(P < 0.05). Control intestine exhibited 3-fold higher(P < 0.01) relative GD1 a ganglioside content than IBD intestine. GD3 and GD1 a species of ganglioside containing three unsaturated bonds were present in control intestine, but were not detected in IBD intestine. The relative content of PC containing more than two unsaturated bonds was 30% lower in IBD intestine than control intestine(P < 0.05). The relative content of HEXA in IBD intestine was increased 1.7-fold(P < 0.05) and NEU3 was increased 8.3-fold(P < 0.01) compared to normal intestine. Intesti 展开更多
关键词 GANGLIOSIDE PHOSPHOLIPID FATTY acid Lipid Inflamma
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Improvedendoscopicretrogradecholangiopancreatographybrushincreases diagnosticyieldofmalignantbiliarystrictures 被引量:4
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作者 Shieh FK Luong-Player A +5 位作者 Khara HS Liu H Lin F Shellenberger MJ Johal AS Diehl dl 《World Journal of Gastrointestinal Endoscopy》 2014年第7期312-317,共6页
AIM: To determine if a new brush design could im-prove the diagnostic yield of biliary stricture brushings. METHODS: Retrospective chart review was performed of all endoscopic retrograde cholangiopancreatography proce... AIM: To determine if a new brush design could im-prove the diagnostic yield of biliary stricture brushings. METHODS: Retrospective chart review was performed of all endoscopic retrograde cholangiopancreatography procedures with malignant biliary stricture brushing between January 2008 and October 2012. A standard wire-guided cytology brush was used prior to proto-col implementation in July 2011, after which, a new 9 French wire-guided cytology brush(Infinity sampling device, US Endoscopy, Mentor, OH) was used for all cases. All specimens were reviewed by blinded pa-thologists who determined whether the sample waspositive or negative for malignancy. Cellular yield was quantified by describing the number of cell clusters seen. RESULTS: Thirty-two new brush cases were compared to 46 historical controls. Twenty-five of 32 (78%) cases in the new brush group showed abnormal cellular find-ings consistent with malignancy as compared to 17 of 46(37%) in the historical control group(P = 0.0003). There was also a significant increase in the average number of cell clusters of all sizes(21.1 vs 9.9 clusters, P = 0.0007) in the new brush group compared to his-torical controls. CONCLUSION: The use of a new brush design for brush cytology of biliary strictures shows increased di-agnostic accuracy, likely due to improved cellular yield, as evidenced by an increase in number of cellular clus-ters obtained. 展开更多
关键词 Malignant biliary stricture Endoscopic ret-rograde cholangiopancreatography Brush cytology Diagnostic yield CYTOPATHOLOGY
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经皮神经电刺激治疗女性纤维肌痛疗效取决于最初30分钟 被引量:4
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作者 梅相阳(译) 冯智英(校) +2 位作者 Vance CGT Zimmerman MB Dailey dl 《中国疼痛医学杂志》 CAS CSCD 北大核心 2021年第11期806-809,共4页
前期研究表明,经皮神经电刺激(transcutaneous electrical nerve stimulation, TENS)治疗1个月可缓解纤维肌痛(fibromyalgia, FM)女性运动诱发的疼痛和疲劳。该研究再次使用前期TENS治疗FM的研究数据,进行应答者分析,以明确TENS治疗缓... 前期研究表明,经皮神经电刺激(transcutaneous electrical nerve stimulation, TENS)治疗1个月可缓解纤维肌痛(fibromyalgia, FM)女性运动诱发的疼痛和疲劳。该研究再次使用前期TENS治疗FM的研究数据,进行应答者分析,以明确TENS治疗缓解疼痛和疲劳的预测因素,并使用受试者工作特征曲线验证预测模型,确定治疗所需数量(number needed to treat, NNT)和危害所需数量(number needed to harm, NNH)。FM女性病人被随机分配到TENS治疗组、TENS假治疗组和未使用TENS组。随机分组后,受试者接受治疗/假治疗1个月,接着TENS假治疗组和未使用TENS组再接受TENS治疗1个月。预测模型使用TENS治疗组(n=103)数据构建,并用TENS假治疗组和未使用TENS组(n=155)在后继TENS治疗1个月后的数据进行验证。使用逻辑回归模型筛选受试者特征、疼痛和疲劳对TENS治疗的初始反应、睡眠和心理等,以确定其与疼痛或疲劳变化之间的关系。疼痛包括TENS治疗后疼痛初始反应和病人疼痛广泛指数(AUC为0.80;95%置信区间:0.73-0.87)。疲劳改善的预测因素包括对TENS治疗的初始反应、婚姻状况和睡眠障碍(AUC为0.67;95%置信区间:0.58-0.75)。疼痛和疲劳的NNT为3.3-5.3,NNH为20-100。若最初30分钟TENS治疗有效则该FM女性病人长期使用TENS有效,而且该模型得到了后继的临床验证。NNT和NNH的结果表明TENS对管理FM女性病人的疼痛和疲劳安全有效。 展开更多
关键词 疼痛 纤维肌痛 经皮神经电刺激 运动痛 疲劳
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环境雌激素能够引起乳腺癌吗? 被引量:2
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作者 Davis,dl 刘义思 《科学(中文版)》 1996年第2期42-48,共7页
关键词 乳腺癌 异雌激素 激素
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土坝失事洪水演算模型—BREACH模型 被引量:3
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作者 Fread,dl 刘晓伟 《水文科技情报》 1991年第4期48-50,共3页
关键词 土坝 洪水 计算 BREACH模型
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