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A high resolution inversion method for fluid factor with dynamic dryrock V_(P)/V_(S) ratio squared
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作者 Lin Zhou Jian-Ping Liao +3 位作者 Xing-Ye Liu Pu Wang Ya-Nan Guo Jing-Ye Li 《Petroleum Science》 SCIE EI CSCD 2023年第5期2822-2834,共13页
As an important indicator parameter of fluid identification,fluid factor has always been a concern for scholars.However,when predicting Russell fluid factor or effective pore-fluid bulk modulus,it is necessary to intr... As an important indicator parameter of fluid identification,fluid factor has always been a concern for scholars.However,when predicting Russell fluid factor or effective pore-fluid bulk modulus,it is necessary to introduce a new rock skeleton parameter which is the dry-rock VP/VS ratio squared(DVRS).In the process of fluid factor calculation or inversion,the existing methods take this parameter as a static constant,which has been estimated in advance,and then apply it to the fluid factor calculation and inversion.The fluid identification analysis based on a portion of the Marmousi 2 model and numerical forward modeling test show that,taking the DVRS as a static constant will limit the identification ability of fluid factor and reduce the inversion accuracy.To solve the above problems,we proposed a new method to regard the DVRS as a dynamic variable varying with depth and lithology for the first time,then apply it to fluid factor calculation and inversion.Firstly,the exact Zoeppritz equations are rewritten into a new form containing the fluid factor and DVRS of upper and lower layers.Next,the new equations are applied to the four parameters simultaneous inversion based on the generalized nonlinear inversion(GNI)method.The testing results on a portion of the Marmousi 2 model and field data show that dynamic DVRS can significantly improve the fluid factor identification ability,effectively suppress illusion.Both synthetic and filed data tests also demonstrate that the GNI method based on Bayesian deterministic inversion(BDI)theory can successfully solve the above four parameter simultaneous inversion problem,and taking the dynamic DVRS as a target inversion parameter can effectively improve the inversion accuracy of fluid factor.All these results completely verified the feasibility and effectiveness of the proposed method. 展开更多
关键词 fluid factor Dry-rock V_(P)/V_(S)ratio squared(DVRS) Dynamic variable Multiple parameters simultaneous inversion Generalized nonlinear inversion(GNI)
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Application of fluid modulus inversion to complex lithology reservoirs in deep-water areas
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作者 Zhaoming Chen Huaxing Lyu +2 位作者 Zhongtao Zhang Yanhui Zhu Baojun Liu 《Energy Geoscience》 EI 2024年第1期153-161,共9页
It has been a challenge to distinguish between seismic anomalies caused by complex lithology and hydrocarbon reservoirs using conventional fluid identification techniques,leading to difficulties in accurately predicti... It has been a challenge to distinguish between seismic anomalies caused by complex lithology and hydrocarbon reservoirs using conventional fluid identification techniques,leading to difficulties in accurately predicting hydrocarbon-bearing properties and determining oil-water contacts in reservoirs.In this study,we built a petrophysical model tailored to the deep-water area of the Baiyun Sag in the eastern South China Sea based on seismic data and explored the feasibility of the tri-parameter direct inversion method in the fluid identification of complex lithology reservoirs,offering a more precise alternative to conventional techniques.Our research found that the fluid modulus can successfully eliminate seismic amplitude anomalies caused by lithological variations.Furthermore,the seismic databased direct inversion for fluid modulus can remove the cumulative errors caused by indirect inversion and the influence of porosity.We discovered that traditional methods using seismic amplitude anomalies were ineffective in detecting fluids,determining gas-water contacts,or delineating high-quality reservoirs.However,the fluid factor Kf,derived from solid-liquid decoupling,proved to be sensitive to the identification of hydrocarbon-bearing properties,distinguishing between high-quality and poor-quality gas zones.Our findings confirm the value of the fluid modulus in fluid identification and demonstrate that the tri-parameter direct inversion method can significantly enhance hydrocarbon exploration in deep-water areas,reducing associated risks. 展开更多
关键词 fluid identification Seismic fluid factor Solid-liquid decoupling Deep-water area Complex lithology reservoir
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Seismic wave scattering inversion for fluid factor of heterogeneous media 被引量:12
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作者 YIN XingYao ZONG ZhaoYun WU GuoChen 《Science China Earth Sciences》 SCIE EI CAS 2014年第3期542-549,共8页
Elastic wave inverse scattering theory plays an important role in parameters estimation of heterogeneous media.Combining inverse scattering theory,perturbation theory and stationary phase approximation,we derive the P... Elastic wave inverse scattering theory plays an important role in parameters estimation of heterogeneous media.Combining inverse scattering theory,perturbation theory and stationary phase approximation,we derive the P-wave seismic scattering coefficient equation in terms of fluid factor,shear modulus and density of background homogeneous media and perturbation media.With this equation as forward solver,a pre-stack seismic Bayesian inversion method is proposed to estimate the fluid factor of heterogeneous media.In this method,Cauchy distribution is utilized to the ratios of fluid factors,shear moduli and densities of perturbation media and background homogeneous media,respectively.Gaussian distribution is utilized to the likelihood function.The introduction of constraints from initial smooth models enhances the stability of the estimation of model parameters.Model test and real data example demonstrate that the proposed method is able to estimate the fluid factor of heterogeneous media from pre-stack seismic data directly and reasonably. 展开更多
关键词 非均匀介质 地震波散射 地震反演 流体 因子 模型参数估计 散射理论 剪切模量
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Amniotic fluid: Source of trophic factors for the developingintestine 被引量:3
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作者 Soham Dasgupta Shreyas Arya +1 位作者 Sanjeev Choudhary Sunil K Jain 《World Journal of Gastrointestinal Pathophysiology》 CAS 2016年第1期38-47,共10页
The gastrointestinal tract(GIT) is a complex system, which changes in response to requirements of the body. GIT represents a barrier to the external environment. To achieve this, epithelial cells must renew rapidly. T... The gastrointestinal tract(GIT) is a complex system, which changes in response to requirements of the body. GIT represents a barrier to the external environment. To achieve this, epithelial cells must renew rapidly. This renewal of epithelial cells starts in the fetal life under the influence of many GIT peptides by swallowing amniotic fluid(AF). Development and maturation of GIT is a very complex cascade that begins long before birth and continues during infancy and childhood by breastfeeding. Many factors like genetic preprogramming, local and systemic endocrine secretions and many trophic factors(TF) from swallowed AF contribute and modulate the development and growth of the GIT. GIT morphogenesis, differentiation and functional development depend on the activity of various TF in the AF. This manuscript will review the role of AF borne TF in the development of GIT. 展开更多
关键词 Amniotic fluid GASTROINTESTINAL factorS TRACT TROPHIC Development
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Heat transfer and friction factor of Therminol liquid phase heat transfer fluid in a ribbed tube 被引量:2
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作者 Weiguo Xu Guodong Liu +3 位作者 Qinghong Zhang Shuai Wang Huilin Lu Heping Tan 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第10期1343-1351,共9页
Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch an... Experiments and simulations on flow and heat transfer behavior of Therminol-55 liquid phase heat transfer fluid have been conducted in a ribbed tube with the outer diameter and inner diameter 25.0 and 20.0 mm,pitch and rib height of 4.5 and 1.0 mm.respectively.Experimental results show that the heat transfer and thermal performance of Therminol-55 liquid phase heat transfer fluid in the ribbed tube are considerably improved compared to those of the smooth tube.The Nusselt number increase with the increase of Reynolds number.The increase in heat transfer rate of the ribbed tube has a mean value of 2.24 times.Also,the pressure drop results reveal that the average friction factor of the ribbed tube is in a range of 2.4 and 2.8 times over the smooth tube.Numerical simulations of three-dimensional flow behavior of Therminol-55 liquid phase heat transfer fluid are carried out using three different turbulence models in the ribbed tube.The numerical results show that the heat transfer of ribbed tube is improved because vortices are generated behind ribs,which produce some disruptions to fluid flow and enhance heat transfer compared with smooth tube.The numerical results prove that the ribbed tube can improve heat transfer and fluid flow performances of Therminol liquid phase heat transfer fluid. 展开更多
关键词 液相流动 传热速率 热流体 导热油 螺纹管 摩擦因子 数值模拟 流动特性
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Changes of Nerve Growth Factor in Amniotic Fluid and Correlation with Ventriculomegaly 被引量:1
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作者 Xiao-yan Xia Xing-hua Huang +1 位作者 Yi-xin Xia Wei-hua Zhang 《Chinese Medical Sciences Journal》 CAS CSCD 2011年第2期109-112,共4页
Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied sub... Objective To detect the change of nerve growth factor (NGF) level in human amniotic fluid during gestation, and to explore the relationship between this change and fetal ventriculo-megaly (VM). Methods The studied subjects (collected from 2004 to 2007) were divided into four groups, including the second-trimester pregnancy group (n=113), third-trimester pregnancy group (n=110), fetal cerebral VM group (n=12), and healthy control group (n=12) which matched with the VM group in gestational weeks. The amniotic fluid specimens were obtained during amniocentesis or cesarean section. The NGF levels in amniotic fluid were detected with en-zyme-linked immunosorbent assay. Results A significantly negative correlation was found between gestational age and the NGF level in amniotic fluid (r= 0.6149, P<0.0001). The NGF level in patients with fetal VM was significantly lower than that in healthy controls (33.95±29.24 pg/mL vs. 64.73±16.21 pg/mL, P=0.024). Conclusion NGF levels in amniotic fluid may be a sensitive marker for fetal VM. 展开更多
关键词 神经生长因子 羊水 酶联免疫吸附 试验检测 NGF 对照组 妊娠期
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Elevated Vascular Endothelia Growth Factor-A in the Serum and Peritoneal Fluid of Patients with Endometriosis 被引量:6
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作者 汪宏波 李艳辉 +2 位作者 冯地路 王泽华 张媛 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2009年第5期637-641,共5页
There has been emergence of evidence suggesting that specific variants of the vascular endothelia growth factor (VEGF) family, based on their ability to regulate angiogenesis, would be pivotal in the pathogenesis of... There has been emergence of evidence suggesting that specific variants of the vascular endothelia growth factor (VEGF) family, based on their ability to regulate angiogenesis, would be pivotal in the pathogenesis of endometriosis. This study was aimed at determining whether high levels of VEGF-A could be found in the serum and peritoneal fluid (PF) of patients with endometriosis. VEGF-A levels were measured by enzyme-linked immunosorbent assay (ELISA) in serum and PF from 46 patients with surgically confirmed endometriosis, and 40 controls with no clinical evidence of the disease or detectable endometriotic lesions at the time of surgical examination. The results showed the mean VEGF-A levels were significantly higher in the serum and PF of patients with endometriosis than in the controls. The VEGF-A levels in the serum and PF of patients with severe endometriosis (stages Ⅲ-Ⅳ) were significantly higher than in those with minimal endometriosis (P〈0.001). It was concluded that endometriosis was associated with significant modulation in the levels of circulating VEGF-A. 展开更多
关键词 vascular endothelial growth factor-A ENDOMETRIOSIS peritoneal fluid REPRODUCTION
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Mechanism of Elevated Vascular Endothelial Growth Factor Levels in Peritoneal Fluids from Patients with Endometriosis
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作者 刘义 吕立群 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2004年第5期470-472,共3页
In order to investigate the mechanism of elevated vascular endothelial growth factor (VEGF) in peritoneal fluids from patients with endometriosis, macrophages were recovered from peritoneal fluids obtained at the time... In order to investigate the mechanism of elevated vascular endothelial growth factor (VEGF) in peritoneal fluids from patients with endometriosis, macrophages were recovered from peritoneal fluids obtained at the time of diagnostic laparoscopy from infertile women with endometriosis (EMT group, n=20) and without endometriosis (control group, n=20). Macrophages were cultured in vitro. The VEGF levels of peritoneal fluid and the supernatant of macrophages culture were determined by enzyme linked immunoassay (ELISA). Meanwhile, the eutopic (n=20) and ectopic endometrium (n=20) from endometriosis patients, and normal edometrium (n=20) from non-endometriosis patients were obtained for the analysis of VEGF expression by labeled Streptavidin Biotin (LSAB). It was found that VEGF levels in peritoneal fluid and macrophages culture supernatant were significantly higher in EMT group than in control group (P<0.01). In normal endometrium, VEGF showed a cyclic changes and similar in eutopic and ectopic endometrium from patients with endometriosis. There was no difference in the intensity of VEGF in endometrium between two groups within each menstrual phase. It is suggested that altered VEGF production by peritoneal macrophages and ectopic endometrium secretion may contribute to the elevated VEGF levels in the peritoneal fluid of patients with endometriosis. 展开更多
关键词 ENDOMETRIOSIS MACROPHAGE peritoneal fluid vascular endothelial growth factor
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Relationship between endogenous digitalis-like factor and fluid therapy in burn-blast combined injury
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作者 朱佩芳 徐有奇 +4 位作者 周继红 周元国 袁立功 刘大为 刘怀林 《Journal of Medical Colleges of PLA(China)》 CAS 1995年第3期182-185,共4页
Fifty dogs were inflicted with burn-blast combined injury and divided into 5 groups. All the experimental animals began to receive various amounts of fluid and sodium slat replacement 2 h after injury. Serum level of ... Fifty dogs were inflicted with burn-blast combined injury and divided into 5 groups. All the experimental animals began to receive various amounts of fluid and sodium slat replacement 2 h after injury. Serum level of endogenous digitalis-like factor (EDLF 展开更多
关键词 ENDOGENOUS digitalis-like factor burns blast INJURY fluid THERAPY
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Secretion of nerve growth factor,brain-derived neurotrophic factor,and glial cell-line derived neurotrophic factor in co-culture of four cell types in cerebrospinal fluid-containing medium 被引量:1
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作者 Sanjiang Feng Minghua Zhuang Rui Wu 《Neural Regeneration Research》 SCIE CAS CSCD 2012年第36期2907-2914,共8页
The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal... The present study co-cultured human embryonic olfactory ensheathJng cells, human Schwann cells, human amniotic epithelial cells and human vascular endothelial cells in complete culture medium- containing cerebrospinal fluid. Enzyme linked immunosorbent assay was used to detect nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor secretion in the supernatant of co-cultured cells. Results showed that the number of all cell types reached a peak at 7-10 days, and the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor peaked at 9 days. Levels of secreted nerve growth factor were four-fold higher than brain-derived neurotrophic factor, which was three-fold higher than glial cell line-derived neurotrophic factor. Increasing concentrations of cerebrospinal fluid (10%, 20% and 30%) in the growth medium caused a decrease of neurotrophic factor secretion Results indicated co-culture of human embryonic olfactory ensheathing cells, human Schwann cells human amniotic epithelial cells and human vascular endothelial cells improved the expression of nerve growth factor, brain-derived neurotrophic factor, and glial cell line-derived neurotrophic factor. The reduction of cerebrospinal fluid extravasation at the transplant site after spinal cord injury is beneficial for the survival and secretion of neurotrophic factors from transplanted cells. 展开更多
关键词 olfactory ensheathing cells Schwann cells amniotic epithelial cells vascular endothelial cells nerve growth factor brain-derived neurotrophic factor glial cell line-derived neurotrophic factor cerebrospinal fluid REGENERATION neural regeneration
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齿痛消炎灵颗粒联合甲硝唑对慢性根尖周炎患者根管治疗后炎症和疼痛的影响
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作者 李爽 《中国民康医学》 2024年第10期119-122,共4页
目的:探讨齿痛消炎灵颗粒联合甲硝唑对慢性根尖周炎患者根管治疗后炎症和疼痛的影响。方法:选取2021年10月至2023年10月在该院行根管治疗的95例慢性根尖周炎患者进行前瞻性研究,按照随机数字表法将其分为对照组(n=47)和观察组(n=48)。... 目的:探讨齿痛消炎灵颗粒联合甲硝唑对慢性根尖周炎患者根管治疗后炎症和疼痛的影响。方法:选取2021年10月至2023年10月在该院行根管治疗的95例慢性根尖周炎患者进行前瞻性研究,按照随机数字表法将其分为对照组(n=47)和观察组(n=48)。在根管治疗基础上,对照组口服甲硝唑片治疗,观察组在对照组基础上联合齿痛消炎灵颗粒治疗。比较两组临床疗效,治疗前后牙周指标[牙龈指数(GI)、菌斑指数(PLI)]、龈沟液炎性因子[肿瘤坏死因子-α(TNF-α)、白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)]水平、视觉模拟评分法(VAS)评分,以及不良反应发生率。结果:观察组治疗总有效率为91.67%(44/48),高于对照组的76.60%(36/47),差异有统计学意义(P<0.05);治疗7 d后,观察组GI、PLI、VAS评分及龈沟液TNF-α、IL-1β、IL-6水平均低于对照组,差异有统计学意义(P<0.05);两组不良反应发生率比较,差异无统计学意义(P>0.05)。结论:齿痛消炎灵颗粒联合甲硝唑用于慢性根尖周炎根管治疗患者可提高临床疗效,改善牙周指标,降低龈沟液炎性因子水平,减轻牙齿疼痛,效果优于单用甲硝唑治疗。 展开更多
关键词 慢性根尖周炎 根管治疗 齿痛消炎灵颗粒 甲硝唑 龈沟液 炎性因子 疼痛
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脑脊液IGF-1、β_(2)-MG、HBP与儿童化脓性脑膜炎发生发展的相关性
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作者 李凤艳 周柳 +1 位作者 袁文华 禚志红 《河南医学研究》 CAS 2024年第16期2951-2954,共4页
目的探究脑脊液中胰岛素样生长因子-1(IGF-1)、β_(2)微球蛋白(β_(2)-MG)、肝素结合蛋白(HBP)水平与儿童化脓性脑膜炎疾病发生发展的相关性。方法选取2021年2月至2023年2月郑州大学第一附属医院儿科收治的86例化脓性脑膜炎患儿为研究组... 目的探究脑脊液中胰岛素样生长因子-1(IGF-1)、β_(2)微球蛋白(β_(2)-MG)、肝素结合蛋白(HBP)水平与儿童化脓性脑膜炎疾病发生发展的相关性。方法选取2021年2月至2023年2月郑州大学第一附属医院儿科收治的86例化脓性脑膜炎患儿为研究组,另选取86例非中枢神经系统感染患儿为对照组,比较两组脑脊液IGF-1、β_(2)-MG、HBP水平,探究其与研究组患儿病情严重程度及预后的相关性。结果研究组脑脊液中IGF-1、β_(2)-MG、HBP水平均高于对照组(P<0.05),且对化脓性脑膜炎具有较高的诊断价值,其曲线下面积分别为0.925、0.930、0.850;重度组脑脊液IGF-1、β_(2)-MG、HBP水平高于轻度组(P<0.05);预后不良组脑脊液IGF-1、β_(2)-MG、HBP水平高于预后良好组(P<0.05),且对化脓性脑膜炎预后不良具有较高的预测价值,其曲线下面积分别为0.879、0.854、0.822。结论监测化脓性脑膜炎患儿脑脊液中IGF-1、β_(2)-MG、HBP的水平对于早期诊断、判断病情严重程度以及预测疾病预后具有重要价值。 展开更多
关键词 脑脊液 胰岛素样生长因子-1 β_(2)微球蛋白 肝素结合蛋白 儿童化脓性脑膜炎
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不同熔附金属对前牙烤瓷熔附金属全冠修复疗效
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作者 杨凤莲 李玉顺 《新疆医学》 2024年第1期57-60,共4页
目的对比研究镍铬合金与金沉积对前牙烤瓷熔附金属(porcelain-fused-to-metal crown,PFM)全冠修复患者的应用效果以及对龈沟液(gingival crevicular fluid,GCF)炎症因子的影响。方法选入2020年9月-2022年2月在本院接受前牙PFM全冠修复... 目的对比研究镍铬合金与金沉积对前牙烤瓷熔附金属(porcelain-fused-to-metal crown,PFM)全冠修复患者的应用效果以及对龈沟液(gingival crevicular fluid,GCF)炎症因子的影响。方法选入2020年9月-2022年2月在本院接受前牙PFM全冠修复的患者86例(86颗牙),根据修复材料不同分为镍铬合金组和金沉积组,每组43例(43颗牙)。比较两组的治疗效果、GCF炎症因子水平等指标。结果金沉积组修复体颜色、边缘密合度、边缘着色及继发龋均显著优于镍铬合金组(P<0.05),在修复体折裂瓷崩方面,两组无明显差异(P>0.05);修复6个月后,金沉积组GI、PD、GCF和GCF中TNF-α、IL-6、IL-1β和MMP-2水平水平均显著低于镍铬合金组(P<0.05);金沉积组满意度显著高于镍铬合金组(93.02%vs.74.42%,P<0.05)。结论镍铬合金与金沉积均是前牙PFM全冠修复的常用材料,而后者对患者局部牙周组织影响较小,在减轻GCF炎性因子水平、提高修复美观度及患者满意度方面优于前者。 展开更多
关键词 烤瓷熔附金属全冠 镍铬合金 金沉积 龈沟液炎症因子 疗效观察
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基于Q弹性阻抗流体因子反演研究
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作者 张如一 文欢 +3 位作者 马永强 田建华 黄超 赵茂强 《石油物探》 CSCD 北大核心 2024年第4期826-832,共7页
流体因子反演的难题在于地层介质的正问题从弹性过渡到非弹性介质后如何建立非弹性介质的反射系数表达式,从而更精确地描述传播介质。针对地震波在非弹性介质中的衰减问题,建立了基于Q弹性流体因子理论,结合衰减系数对弹性流体因子项进... 流体因子反演的难题在于地层介质的正问题从弹性过渡到非弹性介质后如何建立非弹性介质的反射系数表达式,从而更精确地描述传播介质。针对地震波在非弹性介质中的衰减问题,建立了基于Q弹性流体因子理论,结合衰减系数对弹性流体因子项进行扰动获得Q弹性流体因子,在相似介质和弱衰减假设条件下推导了Q弹性流体因子在介质分界面上的散射方程,该表达式与复数条件下的纵、横波速度项及密度项有较高的相关度;进一步通过Q弹性流体因子推导了与纵横波速度的关系,获得了近似条件下Q弹性流体因子纵波反射系数表达式,并分析了该表达式与完全弹性介质反射系数表达式的联系,该方法消除了反演剖面中存在的虚假亮点干扰,从而对衰减弹性介质假设下的储层流体响应进行了更准确的描述。在胜利油田某实际工区的应用结果表明:对流体和围岩进行了区分,获得了相比于常规流体因子反演结果更准确的储层流体响应特征,该流体检测方法在一定程度上降低了流体检测的多解性,消除了仅考虑振幅影响的识别假象。 展开更多
关键词 Q弹性阻抗 粘弹性介质 流体因子 储层反演 衰减系数 流体检测
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无托槽隐形矫治器与金属自锁矫治器对成人正畸患者牙周健康的影响
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作者 辛鑫 许云海 郭涛 《河北医药》 CAS 2024年第13期1974-1977,1981,共5页
目的 对比无托槽隐形矫治器和金属自锁托槽矫治器对成人正畸患者牙周健康的影响。方法 选取2019至2022年就诊的正畸患者200例,根据矫治方法可分为无托槽隐形矫治器组(隐形组)和金属自锁托槽矫治器组(托槽组),每组100例。比较2组患者正... 目的 对比无托槽隐形矫治器和金属自锁托槽矫治器对成人正畸患者牙周健康的影响。方法 选取2019至2022年就诊的正畸患者200例,根据矫治方法可分为无托槽隐形矫治器组(隐形组)和金属自锁托槽矫治器组(托槽组),每组100例。比较2组患者正畸前后不同时间点的菌斑指数(plaque index, PI)、牙龈指数(gingival index, GI)、龈沟出血指数(SBI)和探诊深度(PD),检测患者正畸前后龈沟液中天冬氨酸转氨酶(AST)、碱性磷酸酶(ALP)、白介素1β(IL-1β)、白介素6(IL-6)、肿瘤坏死因子-α(TNF-α)和细胞核因子κB受体活化子配体(RANKL)的表达。结果 2组患者矫正后的PI、GI和SBI均高于矫正前,但隐形组的各项指数明显更低(P<0.05)。2组患者矫正前后不同时间点PD比较,差异无统计学意义(P>0.05)。2组患者矫治后的AST、ALP、IL-1β、IL-6、TNF-α和RANKL表达均明显升高(P<0.05),且隐形组显著低于托槽组(P<0.05)。结论 虽然两种矫治器均对患者的牙周健康产生不良影响,但无托槽隐形矫治后患者的牙周健康指数明显更优,龈沟液中酶及炎性因子的表达明显更少,无托槽隐形器更利于维护患者的牙周健康。 展开更多
关键词 隐形矫治器 自锁托槽 龈沟液 炎性因子 牙周健康
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钻井液侵入纹层状页岩的模型
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作者 索彧 李芬芬 +4 位作者 何文渊 付晓飞 潘哲君 冯福平 赵万春 《工程科学学报》 EI CSCD 北大核心 2024年第3期547-555,共9页
井壁失稳一直是钻井工程中的世界性技术难题,纹层状页岩弱面发育以及黏土矿物含量较高,导致井眼坍塌的风险增加,极大地制约了页岩水平井的高效开发.为了研究钻井液在纹层状页岩中的侵入规律,开展了驱替实验和核磁扫描,确定了不同驱替时... 井壁失稳一直是钻井工程中的世界性技术难题,纹层状页岩弱面发育以及黏土矿物含量较高,导致井眼坍塌的风险增加,极大地制约了页岩水平井的高效开发.为了研究钻井液在纹层状页岩中的侵入规律,开展了驱替实验和核磁扫描,确定了不同驱替时间下钻井液侵入纹层状页岩的深度,基于实验结果建立了新的包含纹层侵入的纹层状页岩的流体侵入数学模型,在总吸水量一定的情况下,可以根据侵入时间求得钻井液在纹层的侵入深度以及侵入量,基于实验结果验证了模型的准确性,采用有限元-离散元法描述钻井液侵入过程并进行敏感性分析.研究结果表明:在钻井液使用量一定的条件下,钻井液沿纹层状页岩油的侵入深度与侵入时间呈正向对数关系,随着侵入时间、纹层张开度的增大,侵入深度逐渐变大,但后期增长缓慢最终趋于不变;随着纹层数量的增加,侵入深度逐渐减小. 展开更多
关键词 页岩 纹层状 钻井液 侵入模型 影响因素
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Fluid discrimination incorporating viscoelasticity and frequency-dependent amplitude variation with offsets inversion 被引量:2
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作者 Zhao-Yun Zong Yan-Wen Feng +2 位作者 Xing-Yao Yin Kun Li Guang-Zhi Zhang 《Petroleum Science》 SCIE CAS CSCD 2021年第4期1047-1058,共12页
Frequency-dependent amplitude versus offset(FAVO)inversion is a popular method to estimate the frequency-dependent elastic parameters by using amplitude and frequency information of pre-stack seismic data to guide flu... Frequency-dependent amplitude versus offset(FAVO)inversion is a popular method to estimate the frequency-dependent elastic parameters by using amplitude and frequency information of pre-stack seismic data to guide fluid identification.Current frequency-dependent AVO inversion methods are mainly based on elastic theory without the consideration of the viscoelasticity of oil/gas.A fluid discrimination approach is proposed in this study by incorporating the viscoelasticity and relevant FAVO inversion.Based on viscoelastic and rock physics theories,a frequency-dependent viscoelastic solid-liquid decoupling fluid factor is initially constructed,and its sensitivity in fluid discrimination is compared with other conventional fluid factors.Furthermore,a novel reflectivity equation is derived in terms of the viscoelastic solid-liquid decoupling fluid factor.Due to the introduction of viscoelastic theory,the proposed reflectivity is related to frequency,which is more widely applicable than the traditional elastic reflectivity equation directly derived from the elastic reflectivity equation on frequency.Finally,a pragmatic frequency-dependent inversion method is introduced to verify the feasibility of the equation for frequency-dependent viscoelastic solid-liquid decoupling fluid factor prediction.Synthetic and field data examples demonstrate the feasibility and stability of the proposed approach in fluid discrimination. 展开更多
关键词 Frequency-dependent VISCOELASTICITY Solid-liquid decoupling fluid factor FAVO inversion fluid discrimination
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IPS e.max press热压铸造陶瓷全冠及二氧化锆全瓷冠对前牙修复患者牙龈健康美观度的影响
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作者 刘小瑜 陈西文 +2 位作者 庄梦瑶 张美玲 刘佳佳 《河北医学》 CAS 2024年第7期1140-1145,共6页
目的:比较IPS e.max press热压铸造陶瓷全冠及二氧化锆全瓷冠对前牙修复患者牙龈健康、美观度的影响,为前牙美学修复的材料选择提供临床参考。方法:以2021年5月至2022年5月于我院接受前牙修复的104例患者为研究对象,以随机数字表法分为... 目的:比较IPS e.max press热压铸造陶瓷全冠及二氧化锆全瓷冠对前牙修复患者牙龈健康、美观度的影响,为前牙美学修复的材料选择提供临床参考。方法:以2021年5月至2022年5月于我院接受前牙修复的104例患者为研究对象,以随机数字表法分为两组,分别52例。观察组、对照组分别以IPS e.max press铸瓷全冠、二氧化锆全瓷冠修复,比较两组患者的临床修复效果及修复后的牙龈指数、菌斑指数、龈沟出血指数、龈沟液炎性因子水平。结果:观察组边缘密合度、继发龋情况均优于对照组(P<0.05);修复后,观察组牙龈指数、菌斑指数等显著小于对照组,龈沟液IL-6、IL-8及TNF-α水平显著低于对照组(P<0.05);修复12个月后,观察组PES评分高于对照组(P<0.05)。结论:相比于二氧化锆全瓷冠,IPS e.max press铸瓷全冠具有良好的前牙美学修复效果,可降低龈沟液炎性因子水平,改善牙龈健康,并能提高前牙美观度。 展开更多
关键词 IPS e.max press铸瓷全冠 二氧化锆全瓷冠 牙龈指数 龈沟液 炎性因子
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脑积水腰大池⁃腹腔分流术预后影响因素分析
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作者 赵浩 曲鑫 +3 位作者 王宁 尚峰 徐跃峤 齐猛 《中国现代神经疾病杂志》 CAS 北大核心 2024年第6期450-454,共5页
目的筛查脑积水患者腰大池⁃腹腔分流术后短期神经功能预后的影响因素。方法纳入2014年10月至2020年1月在首都医科大学宣武医院行腰大池⁃腹腔分流术的136例脑积水患者,出院时采用改良Rankin量表(mRS)评价脑积水术后短期神经功能预后,单... 目的筛查脑积水患者腰大池⁃腹腔分流术后短期神经功能预后的影响因素。方法纳入2014年10月至2020年1月在首都医科大学宣武医院行腰大池⁃腹腔分流术的136例脑积水患者,出院时采用改良Rankin量表(mRS)评价脑积水术后短期神经功能预后,单因素和多因素Logistic回归分析筛查术后短期神经功能预后不良的影响因素。结果共136例患者根据出院时mRS评分分为预后良好(mRS评分≤3分)组(65例)和预后不良(mRS评分>3分)组(71例),Logistic回归分析,入院时Glasgow昏迷量表(GCS)评分9~12分(OR=7.800,95%CI:7.205~8.443;P=0.000)和3~8分(OR=6.299,95%CI:5.744~6.907;P=0.006),病因为颅脑创伤(OR=27.681,95%CI:24.270~31.572;P=0.000)、脑出血(OR=13.017,95%CI:11.473~14.769;P=0.005)、蛛网膜下腔出血(OR=17.682,95%CI:15.683~19.935;P=0.001)和其他原因(OR=5.851,95%CI:5.166~6.628;P=0.050)是脑积水患者腰大池⁃腹腔分流术后短期神经功能预后不良的危险因素。结论脑积水患者腰大池⁃腹腔分流术后神经功能预后受多种因素影响,不同入院时GCS评分、不同病因患者预后不同,应根据具体情况制定个性化治疗方案。 展开更多
关键词 脑积水 脑脊髓液分流术 预后 危险因素 LOGISTIC模型
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储层流体可动性在油田开发中的应用及展望 被引量:1
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作者 谭锋奇 马春苗 +1 位作者 黎宪坤 静禹钱 《西南石油大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期1-20,共20页
储层微观孔喉内流体可动性研究对于储层的精确评价和油藏的高效开发具有重要意义,是油气藏提高采收率的必要条件。依据研究对象的差异性,将孔喉流体可动性的研究方法分为矿物成分、孔隙结构及流体动用3个维度。核磁共振技术能够快速准... 储层微观孔喉内流体可动性研究对于储层的精确评价和油藏的高效开发具有重要意义,是油气藏提高采收率的必要条件。依据研究对象的差异性,将孔喉流体可动性的研究方法分为矿物成分、孔隙结构及流体动用3个维度。核磁共振技术能够快速准确地确定可动流体饱和度、可动流体孔隙度和束缚水饱和度等常用的可动流体参数,进而有效地对各类油气储层进行流体评价和产能预测。目前,国内外各大油田均采用核磁共振与其他实验手段相结合的方法来确定储层内流体的动用规律,并在致密砂砾岩、碳酸盐岩、煤层和油页岩等不同类型储层中取得了良好的应用效果。另外,为了达到对不同类型油气资源的有效勘探和高效开发,必须明确储层内流体可动性的控制因素。在已有研究成果的基础上,流体可动性控制因素可以分为宏观和微观两方面,其中,宏观因素主要包括沉积环境、成岩作用和岩相类型;微观因素主要包括孔喉结构、储层物性、矿物成分及水膜厚度等。目前,虽然流体可动性研究方法的种类已较为丰富,并且在不同类型油气资源的评价中取得了良好的应用效果,但是,在其应用的广度和精度上还需要进一步深入研究与探索,在后续的发展中可综合应用孔隙网络模型、油藏数值模拟、多参数评价指标以及联立地球化学参数等新思路和新方法,深入揭示微观孔喉流体可动性的渗流机理,不断提高可动流体综合评价的精度,为油藏开发方案的合理制定提供地质依据,推动石油行业的高效发展。 展开更多
关键词 流体可动性 研究方法 影响因素 致密储层 核磁共振技术
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