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Missed diagnosis of early gastric cancer or high-grade intraepithelial neoplasia 被引量:64
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作者 Wei Ren Jin Yu +3 位作者 Zhi-Mei Zhang Yuan-Kun Song Yi-Hui Li Lei Wang 《World Journal of Gastroenterology》 SCIE CAS 2013年第13期2092-2096,共5页
AIM: To investigate the causes of missed diagnosis of early gastric cancer (EGC) or high-grade intraepithelial neoplasia (HGIN) in Chongqing, China. METHODS: The present study summarizes 103 cases of EGC/HGIN detected... AIM: To investigate the causes of missed diagnosis of early gastric cancer (EGC) or high-grade intraepithelial neoplasia (HGIN) in Chongqing, China. METHODS: The present study summarizes 103 cases of EGC/HGIN detected by esophagogastroduodenos-copy (EGD) and pathological analysis from January 2010 to December 2011. Dimethyl silicone oil was administrated orally 15 min before the EGD procedures. The stomach was cleaned by repeated washing with saline when the gastroscope entered the stomach cavity. Suspected EGC lesions were subject to conventional biopsy sampling and pathological examinations. The correlation between lesion locations, endoscopic morphology of cancerous sites, training level of the examiners, pathological biopsies, and missed diagnosis was analyzed. RESULTS: Twenty-three cases were missed among the 103 cases (22.23%) of EGC/HGIN. The rate of missed EGC in the gastroesophageal junction (8/19, 42.1%) was significantly higher than at other sites (15/84, 17.86%) (χ2 = 5.253, P = 0.022). In contrast, the rate of missed EGC in the lower stomach body (2/14, 14.29%) was lower than at other sites (21/89,23.6%), but there were no significant differences (χ2 = 0.289, P = 0.591). The rate of missed EGC in the gastric antrum (5/33, 15.15%) was lower than at other sites (18/70, 25.71%), but there were no significant differences (χ2 = 1.443, P = 0.230). Endoscopists from less prestigious hospitals were more prone to not diagnosing EGC than those from more prestigious hospitals (χ2 = 4.261, P = 0.039). When the number of biopsies was < 4, the rate of missed diagnosis was higher (20/23, 89.96%) than for when there were > 4 biopsies (3/23, 13.04%) (P < 0.001). In addition, there was no significant difference in the rate of missed diagnosis in patients with 1-3 biopsy specimens (χ2 = 0.141, P = 0.932). CONCLUSION: Endoscopists should have a clear understanding of the anatomical characteristics of the esophagus/stomach, and endoscopic identification of early lesions increases with the number of biopsies. 展开更多
关键词 MISSED DIAGNOSIS Early GASTRIC cancer high-grade intraepithelial NEOPLASIA Endoscopic DIAGNOSIS BIOPSIES
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SHRIMP single zircon U-Pb dating of the Kongling high-grade metamorphic terrain: Evidence for >3.2 Ga old continental crust in the Yangtze craton 被引量:46
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作者 高山 凌文黎 +2 位作者 QIU Yumin Neal J.McNaughton David I.Groves 《Science China Earth Sciences》 SCIE EI CAS 2001年第4期326-335,共10页
Single zircons from two trondhjemitic gneisses and two clastic metasedimentary rocks without Eu anomaly of the Kongling high-grade metamorphic terrain are dated by the in situ SHRIMP U-Pb method. The results show that... Single zircons from two trondhjemitic gneisses and two clastic metasedimentary rocks without Eu anomaly of the Kongling high-grade metamorphic terrain are dated by the in situ SHRIMP U-Pb method. The results show that the trondhjemitic magma emplaced at 2947-2903 Ma. Concordant age of as old as 3.3 Ga is present in the detrital zircons from the clastic metasedimentary rocks. Together with the depleted mantle Nd model age (TDM =3.2-3.3 Ga) of the clastic metasedimentary rocks, this documents the presence of Paleoarchean continental crust in the Yangtze craton. 展开更多
关键词 Kongling high-grade metamorphic terrain zircon U-Pb age SHRIMP Archean Yangtze craton.
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The recognizing of ca. 1.95 Ga tectono-thermal eventin Kong-ling nucleus and its significance for the evolution of Yangtze Block, South China 被引量:29
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作者 LING Wenli GAO Shan +2 位作者 ZHANG Benren ZHOU Lian XU Qidong 《Chinese Science Bulletin》 SCIE EI CAS 2001年第4期326-329,共4页
Some 1.95 Ga metamorphism of high-grade Ar-chean rocks in Kongling terrain, continental nucleus of Yangtze Block, South China, are recognized by Sm-Nd dating. This event is further confirmed by the ages of single zirc... Some 1.95 Ga metamorphism of high-grade Ar-chean rocks in Kongling terrain, continental nucleus of Yangtze Block, South China, are recognized by Sm-Nd dating. This event is further confirmed by the ages of single zircon SHRIMP U-Pb and K-Ar analyses of TTG and (or) paragneisses, and intrusions of potassic-granitic batholith in the region. The coincidence in period between the high-grade metamorphism in the Kongling area and the creation of major basement rocks of its neighborhoods of the Yangtze Block around the Kongling Archean nucleus makes it a favorable explanation for their tectonic connections that, in the whole Yangtze Block there was some tectono-thermal event of ca. 2.0-1.8 Ga, which resulted in the formation of unitive Yangtze basement. 展开更多
关键词 Kongling high-grade METAMORPHIC terrain tectono-thermal event PALEOPROTEROZOIC unitive basement.
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宫颈环形电切术与冷刀锥切术对高级别宫颈上皮内瘤变患者妊娠结局的影响 被引量:30
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作者 李颖颖 张毅 《中国临床研究》 CAS 2021年第5期624-626,共3页
目的探讨宫颈环形电切术(LEEP)和冷刀锥切术(CKC)两种治疗方式对有生育需求的高级别宫颈上皮内瘤变(CIN)患者妊娠结局的影响,为临床治疗提供参考。方法回顾性分析十堰市人民医院2015年1月至2018年12月,因高级别CIN接受LEEP术或CKC术后... 目的探讨宫颈环形电切术(LEEP)和冷刀锥切术(CKC)两种治疗方式对有生育需求的高级别宫颈上皮内瘤变(CIN)患者妊娠结局的影响,为临床治疗提供参考。方法回顾性分析十堰市人民医院2015年1月至2018年12月,因高级别CIN接受LEEP术或CKC术后有妊娠意愿患者81例的临床资料。根据手术方式分为LEEP组(41例)及CKC组(40例),统计两种方式治疗后患者妊娠率、流产率、早产率、胎膜早破发生率、低出生体重儿发生率、剖宫产率等指标。结果 LEEP组和CKC组妊娠率比较差异无统计学意义(90.2%vs 87.5%,P>0.05)。LEEP组流产率(16.2%vs 37.1%)、早产率(5.4%vs 25.7%)、低出生体重儿发生率(8.1%vs 28.6%)、剖宫产率(13.5%vs 42.9%)低于CKC组,差异有统计学意义(P<0.05,P<0.01)。结论行CKC术患者流产、早产、低出生体重儿发生率及剖宫产率高于行LEEP术患者。对于有生育要求的高级别CIN患者,可以考虑选择LEEP治疗。 展开更多
关键词 宫颈上皮内瘤变 高级别 妊娠结局 宫颈环形电切术 宫颈冷刀锥切术
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考虑强度匹配的高钢级管道环焊缝断裂评估方法 被引量:24
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作者 吴锴 张宏 +3 位作者 杨悦 刘啸奔 隋永莉 陈朋超 《油气储运》 CAS 北大核心 2021年第9期1008-1016,共9页
管道环焊缝的实际低强匹配是引发焊缝断裂失效的重要原因,在焊缝的适用性评估中,失效评估图方法无法准确考虑焊缝强度匹配的影响,准确纳入强度匹配成为拓宽失效评估图方法应用于高钢级管道环焊缝裂纹缺陷评估的关键。基于非线性有限元法... 管道环焊缝的实际低强匹配是引发焊缝断裂失效的重要原因,在焊缝的适用性评估中,失效评估图方法无法准确考虑焊缝强度匹配的影响,准确纳入强度匹配成为拓宽失效评估图方法应用于高钢级管道环焊缝裂纹缺陷评估的关键。基于非线性有限元法,建立了高钢级管道环焊缝裂纹驱动力的数值仿真模型,采用等效应力应变关系方法构建了环焊缝裂纹的通用失效评估曲线,采用裂纹驱动力的有限元计算结果,结合BS 7910-2019《金属结构中缺陷可接受性评估方法指南》推荐方法,构建了系列不同载荷水平下的有限元评估点,探明了BS 7910-2019对于环焊缝裂纹缺陷的评估精度,查明了影响评估结果精度的关键原因。在此基础上,考虑裂纹深度、裂纹长度、焊缝强度匹配系数,提出了优化的管道环焊缝极限载荷计算模型以及改进的失效评估图方法,准确将焊缝强度匹配纳入到失效评估图方法中,进一步提高了高钢级管道环焊缝裂纹缺陷的评估精度,可为在役高钢级管道环焊缝裂纹的适用性评估提供参考。(图11,参24) 展开更多
关键词 环焊缝 高钢级 强度匹配 失效评估图 断裂评估
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动脉瘤介入栓塞术治疗动脉瘤性蛛网膜下腔出血的效果 被引量:18
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作者 汪娇 兰军 +1 位作者 肖刚 丁辉 《实用癌症杂志》 2020年第11期1846-1848,1856,共4页
目的探究动脉瘤介入栓塞术对高分级动脉瘤性蛛网膜下腔出血的临床疗效。方法选取高分级动脉瘤性蛛网膜下腔出血患者100例作为研究对象,随机分为观察组50例,对照组50例。观察组采用动脉瘤介入栓塞术治疗,对照组采用颅内动脉瘤夹闭术治疗... 目的探究动脉瘤介入栓塞术对高分级动脉瘤性蛛网膜下腔出血的临床疗效。方法选取高分级动脉瘤性蛛网膜下腔出血患者100例作为研究对象,随机分为观察组50例,对照组50例。观察组采用动脉瘤介入栓塞术治疗,对照组采用颅内动脉瘤夹闭术治疗,比较2组的疗效。结果观察组预后良好率显著高于对照组,差异有统计学意(P<0.05)。观察组重度残疾、植物生存、颅内感染、脑血管痉挛发生率低于对照组,差异具有统计学意义(P<0.05)。观察组术后1 d、7 d各项免疫指标如免疫球蛋白M、免疫球蛋白G、免疫球蛋白A都高于对照组(P<0.05),差异有统计学意义。观察组住院时间短于对照组,且差异有统计学意义(P<0.05)。2组的完全闭塞率和复发率没有明显差异(P>0.05)。结论相较于颅内夹闭术,介入栓塞术治疗高分级动脉瘤性蛛网膜性下腔出血的疗效更佳,且减少了并发症的发生率。 展开更多
关键词 动脉瘤 介入栓塞术 颅内动脉瘤夹闭术 高分级 蛛网膜下腔出血
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Coordinated peak expression of MMP-26 and TIMP-4 in preinvasive human prostate tumor 被引量:18
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作者 Seakwoo Lee Kevin K Desai +6 位作者 Kenneth A Iczkowski Robert G Newcomer Kevin J WU Yun-Ge Zhao Winston W Tan Mark D Roycik Qing-Xiang Amy Sang 《Cell Research》 SCIE CAS CSCD 2006年第9期750-758,共9页
The identification of novel biomarkers for early prostate cancer diagnosis is highly important because early detection and treatment are critical for the medical management of patients. Disruption in the continuity of... The identification of novel biomarkers for early prostate cancer diagnosis is highly important because early detection and treatment are critical for the medical management of patients. Disruption in the continuity of both the basal cell layer and basement membrane is essential for the progression of high-grade prostatic intraepithelial neoplasia (HGPIN) to invasive adenocarcinoma in human prostate. The molecules involved in the conversion to an invasive phenotype are the subject of intense scrutiny. We have previously reported that matrix metalloproteinase-26 (MMP-26) promotes the invasion of human prostate cancer cells via the cleavage of basement membrane proteins and by activating the zymogen form of MMP-9. Furthermore, we have found that tissue inhibitor of metalloproteinases-4 (TIMP-4) is the most potent endogenous inhibitor of MMP-26. Here we demonstrate higher (p〈0.0001) MMP-26 and TIMP-4 expression in HGPIN and cancer, compared to non-neoplastic acini. Their expression levels are highest in HGPIN, but decline in invasive cancer (p〈0.001 for each) in the same tissues. Immunohistochemical staining of serial prostate cancer tissue sections suggests colocalization of MMP-26 and TIMP-4. The present study indicates that MMP-26 and TIMP-4 may play an integral role during the conversion of HGPIN to invasive cancer and may also serve as markers for early prostate cancer diagnosis. 展开更多
关键词 matrix metalloproteinase-26 tissue inhibitor of metalloproteinases-4 high-grade prostatic intraepithel ialneoplasia prostate cancer biomarkers early diagnosis IMMUNOHISTOCHEMISTRY CO-IMMUNOPRECIPITATION
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开颅夹闭术与血管内治疗急性期高分级前循环动脉瘤的短期疗效分析 被引量:17
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作者 许志剑 余丹枫 +1 位作者 徐虎 周格知 《中华神经外科杂志》 CSCD 北大核心 2019年第6期562-566,共5页
目的探讨开颅夹闭术与血管内治疗急性期高分级[世界神经外科联盟(WFNS)分级Ⅳ~Ⅴ级]前循环动脉瘤的短期临床疗效。方法回顾性纳入2014年1月至2018年1月金华市中心医院神经外科收治的162例急性期高分级前循环动脉瘤患者。根据手术方式分... 目的探讨开颅夹闭术与血管内治疗急性期高分级[世界神经外科联盟(WFNS)分级Ⅳ~Ⅴ级]前循环动脉瘤的短期临床疗效。方法回顾性纳入2014年1月至2018年1月金华市中心医院神经外科收治的162例急性期高分级前循环动脉瘤患者。根据手术方式分为开颅夹闭组(88例)和血管内治疗组(74例),比较两组患者的术后并发症和短期随访情况,并采用格拉斯哥预后分级(GOS)评价短期疗效。两组的数据结果采用卡方检验、秩和检验和t检验进行分析。结果两组术后再破裂出血、脑血管痉挛、脑梗死和颅内感染等并发症比较差异均无统计学意义(均P>0.05);而开颅夹闭组(3.4%,3/88)的脑积水发生率低于血管内治疗组(12.2%,9/74)(P<0.05)。随访3~12个月,开颅夹闭组患者的预后良好率(56.8%,50/88)高于血管内治疗组(40.5%,30/74)(P<0.05),尤其是WFNSⅣ级的患者[64.4%(47/73)对比45.2%(28/62),P<0.05];而对于WFNSⅤ级的患者,两种手术方式的预后比较差异无统计学意义(P>0.05)。结论对于急性期高分级的前循环动脉瘤,采用开颅夹闭术治疗并发症较低,而且短期疗效更好。 展开更多
关键词 颅内动脉瘤 高分级 显微外科手术 栓塞 治疗性
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Zircon U-Pb geochronology of Archean high-grade metamorphic rocks from Xi Ulanbulang area,central Inner Mongolia 被引量:16
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作者 DONG XiaoJie XU ZhongYuan +1 位作者 LIU ZhengHong SHA Qian 《Science China Earth Sciences》 SCIE EI CAS 2012年第2期204-212,共9页
The early Precambrian high-grade metamorphosed basement in the Xi Ulanbulang area, central Inner Mongolia of China, is composed mainly of intermediate granulites and charnockitic gneisses. Both types of the rocks are ... The early Precambrian high-grade metamorphosed basement in the Xi Ulanbulang area, central Inner Mongolia of China, is composed mainly of intermediate granulites and charnockitic gneisses. Both types of the rocks are closely associated spatially and temporally, with a gradual variation between them. In order to understand timing of the high-grade metamorphism, we carried out SHRIMP U-Pb dating of zircons of the rocks. Zircons from the granulites and charnockitic gneisses are similar in structure and age. Zircon cores show magmatic zoning and have ages of 2507-2545 Ma. The ages are interpreted as the forming time of protolith of the granulites and charnockitic gneisses, indicating that a strong magmatism existed at that time in the Yinshan Block. The zircon mantles and rims show homogeneous structures and record a strong granulite facies metamorphism event around 2500 Ma, with a time interval between the metamorphism and magamatism being less than 50 Ma. These suggest that the Western Block was similar to the Eastern Block in tectono-thermal timing at the end of the Neoarchean. 展开更多
关键词 Xi Ulanbulang high-grade metamorphic rocks ZIRCON SHRIMP U-Pb dating
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Latest developments in precancerous lesions of hepatocellular carcinoma 被引量:14
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作者 Zhao-Shan Niu Xiao-Jun Niu +1 位作者 Wen-Hong Wang Jing Zhao 《World Journal of Gastroenterology》 SCIE CAS 2016年第12期3305-3314,共10页
Hepatocarcinogenesis in human chronic liver diseases is a multi-step process in which hepatic precancerous lesions progress into early hepatocellular carcinoma(HCC) and progressed HCC, and the close surveillance and t... Hepatocarcinogenesis in human chronic liver diseases is a multi-step process in which hepatic precancerous lesions progress into early hepatocellular carcinoma(HCC) and progressed HCC, and the close surveillance and treatment of these lesions will help improve the survival rates of patients with HCC. The rapid development and extensive application of imaging technology have facilitated the discovery of nodular lesions of ambiguous significance, such as dysplastic nodules. Further investigations showed that these nodules may be hepatic precancerous lesions, and they often appear in patients with liver cirrhosis. Although the morphology of these nodules is not sufficient to support a diagnosis of malignant tumor, these nodules are closely correlated with the occurrence of HCC, as indicated by long-term follow-up studies. In recent years, the rapid development and wide application of pathology, molecular genetics and imaging technology have elucidated the characteristics of precancerous lesions. Based on our extensive review of the relevant literature, this article focuses on evidence indicating that high-grade dysplastic nodules are more likely to transform into HCC than low-grade dysplastic nodules based on clinical, pathological, molecular genetic and radiological assessments. In addition, evidence supporting the precancerous nature of large cell change in hepatitis B virus-related HCC is discussed. 展开更多
关键词 Hepatocellular carcinoma Precancerous lesions high-grade dysplastic nodule Large cell change Small cell change
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浙江省民宿空间分布格局与影响因素研究 被引量:15
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作者 郝倩倩 沈世伟 《资源开发与市场》 CAS 2020年第10期1165-1171,共7页
选取浙江省高等级民宿和未被定级的民宿POI数据为研究样本,运用ArcGIS10.0空间分析和数理统计等方法分析了该省民宿的时空分布规律和集聚特征,揭示了相关因素对民宿分布的影响。结果表明:①浙江省未被定级民宿呈现高度的空间集聚性,与... 选取浙江省高等级民宿和未被定级的民宿POI数据为研究样本,运用ArcGIS10.0空间分析和数理统计等方法分析了该省民宿的时空分布规律和集聚特征,揭示了相关因素对民宿分布的影响。结果表明:①浙江省未被定级民宿呈现高度的空间集聚性,与高等级民宿的空间分布特征及空间扩张趋势呈现明显差异。②未被定级民宿均衡分布于多类地形地带,而高等级民宿在不同海拔地区的分布情况不一,多分布于山地和丘陵地带。③不同等级民宿与区域发展水平、公路网密度、区域内3A级以上景区数量呈现不同程度的空间相关性。 展开更多
关键词 民宿 高等级 未被定级 空间格局 影响因素
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Triage for management of cervical high-grade squamous intraepithelial lesion patients with positive margin by conization: a retrospective analysis 被引量:13
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作者 Yuya Dou Xiaodan Zhang +3 位作者 Yang Li Fenfen Wang Xing Xie Xinyu Wang 《Frontiers of Medicine》 SCIE CAS CSCD 2017年第2期223-228,共6页
The objective of this study is to guide a triage for the management of cervical high-grade squamous intraepithelial lesion (HSIL) patients with positive margin by conization. Clinico-pathological data of HSIL patien... The objective of this study is to guide a triage for the management of cervical high-grade squamous intraepithelial lesion (HSIL) patients with positive margin by conization. Clinico-pathological data of HSIL patients with positive margin by conization were retrospectively collected from January 2009 to December 2014. All patients underwent secondary conization or hysterectomy within 6 months. The rate of residual lesion was calculated, and the factors associated with residual lesion were analyzed by univariate and multivariate analyses. Among a total of 119 patients, 56 (47.06%) patients presented residual HSIL in their subsequent surgical specimens, including 4 cases of invasive cervical carcinoma (3 stage IA1 and 1 stage IA2 patients). Univariate analysis showed that patient age 〉 35 years (P = 0.005), menopausal period 〉 5 years (P = 0.0035), and multiple- quadrant involvement (P=0.001) were significantly correlated with residual disease; however, multivariate analysis revealed that multiple-quadrant involvement (P=0.001; OR, 3.701; 95%CI, 1.496-9.154) was an independent risk factor for residua! disease. Nearly half of HSIL patients with positive margin by conization were disease-free in subsequent surgical specimens, and those with multiple positive margins may consider re- conization or re-assessment. 展开更多
关键词 cervical high-grade squamous intraepithelial lesion CONIZATION positive surgical margin HYSTERECTOMY
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Human papillomavirus(HPV) E6/E7 mRNA detection in cervical exfoliated cells:a potential triage for HPV-positive women 被引量:14
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作者 Ye-li YAO Qi-fang TIAN +3 位作者 Bei CHENG Yi-fan CHENG Jing YE Wei-guo LU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2017年第3期256-262,共7页
Cytology triage has been generally recommended for human papillomavirus (HPV)-positive women, but is highly dependent on well-trained cytologists. The present study was designed to explore whether HPV E6/E7 mRNA det... Cytology triage has been generally recommended for human papillomavirus (HPV)-positive women, but is highly dependent on well-trained cytologists. The present study was designed to explore whether HPV E6/E7 mRNA detection in cervical exfoliated cells can be a potential triage for HPV-positive women from a clinic-based population. Both the primary HPV testing and Papanicolaou (Pap) test were performed on all eligible HPV-positive women. HPV E6/E7 mRNA was detected by QuantiVirus HPV E6/E7 mRNA assay in cervical exfoliated cells. All HPV-positive women underwent colposcopy and further biopsy if indicated. The data were assessed by Pearson's Chi-squared test and the receiver operating characteristic curve. A total of 404 eligible HPV-positive women were enrolled. Positive rate of E6/E7 mRNA in high-grade squamous intraepithelial lesion (HSIL) cases was higher than that in low-grade squamous intraepithelial lesion (LSIL) or normal cases. There was no statistical difference found between mRNA and cytological testing with sensitivity (89.52% vs. 86.67%, P=0.671), specificity (48.96% vs. 48.96%, P=1.000), positive predictive value (39.00% vs. 38.24%, P=1.000), and negative predictive value (92.76% vs. 90.97%, P=-0.678) for detecting ≥HSIL. HPV E6/E7 mRNA detection in cervical exfoliated cells shows the same performance as Pap triage for HSIL identification for HPV-positive women. Detection of HPV E6/E7 mRNA may be used as a new triage option for HPV-positive women. 展开更多
关键词 Human papillomavirus (HPV) HPV E6/E7 mRNA high-grade squamous intraepithelial lesion (HSIL)
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从低品级菱镁矿中提取高纯氧化镁的研究 被引量:10
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作者 章柯宁 张一敏 +1 位作者 王昌安 周文波 《武汉科技大学学报》 CAS 2006年第6期558-560,共3页
采用低品级菱镁矿粉矿进行碳化浸出工艺试验,对菱镁矿的矿石性质及轻烧性能、氧化镁的消化过程和碳化浸出工艺参数进行了研究,获得wMgO大于99%的高纯氧化镁产品。
关键词 氧化镁 碳化法 消化 高纯 菱镁矿
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华北板块北缘首例大型高品位隐伏斑岩型金矿床——内蒙古毕力赫金矿 被引量:12
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作者 葛良胜 卿敏 +5 位作者 张文钊 袁士松 段希刚 马满福 庞继尧 唐明国 《中国地质》 CAS CSCD 北大核心 2009年第5期1110-1122,共13页
内蒙古毕力赫金矿床(II号带)是全国危机矿山接替资源勘查获得重大突破的矿床之一,由武警黄金地质研究所勘查发现(2006—2008年)。矿区位于华北板块北缘叠接俯冲带南部华北板块一侧的陆相火山岩盆地中。该矿床有如下主要特点:(1)矿体呈... 内蒙古毕力赫金矿床(II号带)是全国危机矿山接替资源勘查获得重大突破的矿床之一,由武警黄金地质研究所勘查发现(2006—2008年)。矿区位于华北板块北缘叠接俯冲带南部华北板块一侧的陆相火山岩盆地中。该矿床有如下主要特点:(1)矿体呈隐伏状态(距地表1~40m)产出于隐伏的燕山期花岗闪长斑岩体接触带内,并以内接触带为主;(2)矿体规模大(目前控制长500m,最宽处300m,最窄处约40m,最大厚度128.17m,最小厚度10.53m,平均厚度52.85m),品位高(平均4.5×10-6,最高52.76×10-6),单个矿体资源量达20t以上;(3)矿石为蚀变的花岗闪长斑岩和火山岩型,前者具有典型的单向固结结构(UST)。金属矿物以黄铁矿、黄铜矿、辉钼矿等为主,但含量低(小于1%),金主要赋存于蚀变形成的团块状或细脉状石英中;(4)围岩蚀变以钾化、硅化、绢云母化、高岭土化、青磐岩化等为主,具有富金斑岩型铜矿床的分带特征;(5)成矿温度明显分为两个区间,早期石英流体包裹体均一温度大于550℃,为含矿热液沸腾结果;中晚期温度变化在108~375℃,平均值为194℃。初步研究表明,该矿床应为独立的大型高品位斑岩型金矿床,在华北板块北缘地区为首次发现,具有典型性和代表性,对于区域相似地质环境内类似矿床的寻找和勘查具有重大示范意义。 展开更多
关键词 金矿床 大型 高品位 斑岩型 华北板块北缘 毕力赫 内蒙古
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Geological settings and metallogenesis of high-grade iron deposits in China 被引量:13
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作者 Zhaochong ZHANG Houmin LI +6 位作者 Jianwei LI Xie-Yan SONG Hao HU Lixing LI Fengmei CHAI Tong HOU Deru XU 《Science China Earth Sciences》 SCIE EI CSCD 2021年第5期691-715,共25页
The predominant types of high-grade iron deposits in China include skarn,sedimentary metamorphic(banded ironformation,BIF-type),continental/submarine volcanic-hosted and magmatic Fe-Ti-Voxide deposits.Based on a compr... The predominant types of high-grade iron deposits in China include skarn,sedimentary metamorphic(banded ironformation,BIF-type),continental/submarine volcanic-hosted and magmatic Fe-Ti-Voxide deposits.Based on a comprehensive review of current studies on these deposits,this paper suggests that the oxygen concentration in atmosphere played an important role for the formation of BIFs,whereas the tectonic setting and deep magmatic differentiation processes are more important for the other types.Notably,both high temperature and high pressure experiments and melt inclusion studies indicate that during the differentiation,high temperature magmas could develop iron-rich magma via liquid immiscibility but not pure oxide melt("iron ore magma").Fe-P melt could be generated directly by liquid immiscibility under hydrous and oxidized condition.The formation of high-grade iron deposits is mostly associated with the processes related to multiple stages of superimposition,e.g.,desiliconization and iron enrichment,removal of impurity,and remobilization and re-precipitation of iron.According to the temporal evolution,the high-grade iron deposit could be divided into multi-episode superimposition type(temporally discontinuous mineralization)and multi-stage superimposition type(temporally continuous mineralization).The former is represented by the sedimentary metamorphic iron deposit,and the latter includes those related to magmatic-hydrothermal fluids(e.g.,skarn,volcanic-hosted and magmatic types). 展开更多
关键词 high-grade iron deposit METALLOGENESIS Iron ore magma Liquid immiscibility Fe-rich fluid
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BAYQIK~——高浓度二氧化硫烟气制酸创新工艺 被引量:13
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作者 T. WEBER M. KUERTEN +2 位作者 B. ERKES K. STEMMER 段立文(译) 《硫酸工业》 CAS 2010年第1期1-7,共7页
介绍拜耳技术服务公司开发的准等温接触高浓度二氧化硫烟气制酸创新工艺BAYQIK。详述该工艺的理论基础、反应器结构、模型建立、中间试验以及在铅冶炼烟气制酸装置中的应用。BAYQIK艺的特点在于采用列管式固定床反应器,传统钒催化剂装... 介绍拜耳技术服务公司开发的准等温接触高浓度二氧化硫烟气制酸创新工艺BAYQIK。详述该工艺的理论基础、反应器结构、模型建立、中间试验以及在铅冶炼烟气制酸装置中的应用。BAYQIK艺的特点在于采用列管式固定床反应器,传统钒催化剂装在管内,冷却介质在壳程流动。氧化过程放出的热量被连续移走,从而使催化剂始终处于可承受的最高温度以下,即使反应器进气φ(SO2)超过50%。BAYQIK工艺可提供各种经济和工艺优点,包括可降低投资与操作成本,对于新建装置和扩能改造项目同样适用。 展开更多
关键词 冶炼烟气 高浓度 二氧化硫 硫酸生产 准等温工艺
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Dysfunction of PLA2G6 and CYP2C44-associated network signals imminent carcinogenesis from chronic inflammation to hepatocellular carcinoma 被引量:13
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作者 Meiyi Li Chen Li +14 位作者 Wei-Xin Liu Conghui Liu Jingru Cui Qingrun Li Hong Ni Yingcheng Yang Chaochao Wu Chunlei Chen Xing Zhen Tao Zeng Mujun zhao Lei Chen Jiarui Wu Rong Zeng Luonan Chen 《Journal of Molecular Cell Biology》 SCIE CAS CSCD 2017年第6期489-503,共15页
Little is known about how chronic inflammation contributes to the progression of hepatoceUular carcinoma (HCC), especially the initiation of cancer. To uncover the critical transition from chronic inflammation to HC... Little is known about how chronic inflammation contributes to the progression of hepatoceUular carcinoma (HCC), especially the initiation of cancer. To uncover the critical transition from chronic inflammation to HCC and the molecular mechanisms at a network level, we analyzed the time-series proteomic data of woodchuck hepatitis virus/c.myc mice and age-matched wt-C57BL/6 mice using our dynamical network biomarker (DNB) model. DNB analysis indicated that the 5th month after birth of transgenic mice was the critical period of cancer initiation, just before the critical transition, which is consistent with clinical symptoms. Meanwhile, the DNB-associated network showed a drastic inversion of protein expression and coexpression levels before and after the critical transition. Two members of DNB, PLA2G6 and CYP2C44, along with their associated differentially expressed proteins, were found to induce dysfunction of arachidonic acid metabolism, further activate inflammatory responses through inflammatory mediator regulation of transient receptor potential channels, and finally lead to impairments of liver detoxification and malignant transition to cancer. As a c-Myc target, PLA2G6 positively correlated with c-Myc in expression, showing a trend from decreasing to increasing during carcinogenesis, with the minimal point at the critical transition or tipping point. Such trend of homologous PLA2G6 and c-Myc was also observed during human hepatocarcinogenesis, with the minimal point at high-grade dysplastic nodules (a stage just before the carcinogenesis). Our study implies that PLA2G6 might function as an oncogene like famous c-Myc during hepatocar- cinogenesis, while downregulation of PLA2G6 and c-Myc could be a warning signal indicating imminent carcinogenesis. 展开更多
关键词 dynamical network biomarker inflammation-induced HCC critical transition early diagnosis high-grade dysplasticnodules tipping point
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以供给侧结构性改革推进“高精尖”产业结构的构建——以北京市为例 被引量:12
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作者 田新民 胡颖 《经济与管理研究》 CSSCI 北大核心 2016年第8期32-42,共11页
本文构建北京"高精尖"产业结构指标体系并进行度量,采用2002—2013年31个省级区域数据建立具有时间固定效应的空间杜宾模型,分析供给侧结构性改革对"高精尖"产业结构的影响。回归结果显示:(1)政府基础建设支出对产... 本文构建北京"高精尖"产业结构指标体系并进行度量,采用2002—2013年31个省级区域数据建立具有时间固定效应的空间杜宾模型,分析供给侧结构性改革对"高精尖"产业结构的影响。回归结果显示:(1)政府基础建设支出对产业结构升级的作用逐步减小,而科技支出的作用不断增加;(2)政府税收对产业结构升级的作用由正转负,国有化程度和政府税收成为产业结构升级的阻碍;(3)单纯的金融业数量增加对产业结构升级的作用已经不再显著;(4)国有化程度和金融环境具有负向的空间溢出效应,而政府基础建设支出的溢出效应不显著。根据上述结果,本文提出以结构性减税、国企改革、金融体制改革等供给侧改革方法推进"高精尖"产业结构的构建。 展开更多
关键词 供给侧改革 空间杜宾模型 “高精尖”产业结构
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中国盐改后产业升级探讨 被引量:11
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作者 朱国梁 霍俊霏 丁捷 《盐科学与化工》 CAS 2019年第4期1-6,共6页
中国盐业改革后,环境的变化对行业现状、市场现状和各类生产经营企业都产生了重大的影响。文章主要讨论了盐改后原盐市场和食盐市场的供求关系变化以及食盐安全、产业升级、盐品高端化的发展趋势及展望。
关键词 盐业改革 食盐安全 发展趋势 产业升级 高端化
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