期刊文献+
共找到1,928篇文章
< 1 2 97 >
每页显示 20 50 100
Prevalence of deep venous thrombosis in patients with acute exacerbation of chronic obstructive pulmonary disease 被引量:25
1
作者 DUAN Sheng-chen YANG yuan-hua +6 位作者 LI Xu-yan LIANG Xiao-ning GUO Rui-jun XIE Wan-mu KUANG Tu-guang DAI hua-ping WANG Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2010年第12期1510-1514,共5页
Background Acute exacerbation of chronic obstructive pulmonary disease (COPD) is always associated with a high incidence and mortality. Because of the presence of some concomitant risk factors such as immobilization... Background Acute exacerbation of chronic obstructive pulmonary disease (COPD) is always associated with a high incidence and mortality. Because of the presence of some concomitant risk factors such as immobilization, bronchial superinfection, patients who are admitted for acute exacerbations of COPD are generally considered to be at moderate risk for the development of venous thromboembolism. In this study, we investigated the prevalence and the clinical manifestations of deep venous thrombosis (DVT) in patients with acute exacerbation of COPD.Methods From March 2007 to March 2009, 520 consecutive patients were included in this study. On admission, color Doppler ultrasound of lower extremities in all cases was performed for diagnosing DVT. Patients with DVT were compared with those without DVT from such aspects as demographics, symptoms, physical signs and risk factors.Results Among the 520 patients, DVT was found in 46 cases (9.7%). In patients with DVT, the duration of hospitalization was longer (P=0.01), and the mechanical ventilation requirement increased (P 〈0.001). Other indicators for patients with more possibility of DVT were immobility exceeding 3 days (P 〈0.001); pneumonia as concomitance (P=0.01); respiratory failure type Ⅱ (P=0.013); current smoking (P=0.001). Lower extremity pain was more common in DVT cases in comparison to those without DVT (34.8% vs. 15.2%, P=0.01 ).Conclusions The acute exacerbation of COPD patients, who were immobilized for over 3 days, complicated by pneumonia and had respiratory failure type Ⅱ, had a higher risk of DVT. In addition, DVT detection awareness should be increased in cases that had a lower extremity pain. 展开更多
关键词 Chronic obstructive pulmonary disease deep venous thrombosis ULTRASONOGRAPHY
原文传递
Value of transthoracic echocardiography combined with cardiac troponin I in risk stratification in acute pulmonary thromboembolism 被引量:23
2
作者 ZHU Ling YANG yuan-hua +2 位作者 WU Ya-feng ZHAI Zhen-guo WANG Chen 《Chinese Medical Journal》 SCIE CAS CSCD 2007年第1期17-21,共5页
Background Acute pulmonary thromboembolism (APE) causes right ventricular dysfunction (RVD) and cardiac troponin I (cTnl) elevation. Patients with RVD and cTnl elevation have a worse prognosis. Thus, early detec... Background Acute pulmonary thromboembolism (APE) causes right ventricular dysfunction (RVD) and cardiac troponin I (cTnl) elevation. Patients with RVD and cTnl elevation have a worse prognosis. Thus, early detection of RVD and cTnl elevation is beneficial for risk stratification. In this study, we assessed 14-day adverse clinical events and combined RVD on transthoracic echocardiography (TTE) with cTnl in risk stratification among a broad spectrum of APE patients. Methods The prospective multi-centre trial included 90 patients with confirmed APE from 12 collaborating hospitals. Acute RVD on TTE was diagnosed in the presence of at least 2 of the following: right ventricular dilatation (without hypertrophy), loss of inspiratory collapse of inferior vena cava (IVC), right ventricular (RV) hypokinesis, tricuspid regurgitant jet velocity 〉2.8 m/s. The study patients were divided into two groups according to clinical and echocardiographic findings at presentation: Group Ⅰ: 50 patients with RVD; Group Ⅱ:40 patients without RVD. Results More than half of the patients (50/90, 55.6%) had RVD. Nearly one third (26/90, 28.9%) of patients had elevated cTnl at presentation and only 4.2% on the fourth day after initial therapy. A multiple Logistic regression model implied RVD, right and left ventricular end-diastolic diameter ratio (RVED/LVED), and cTnl independently predict an adverse 14-day clinical outcome (P〈0.01). Receiver operating characteristics (ROC) curves revealed that the cut-off values of RVED/LVED and cTnl yielding the highest discriminating power were 0.65 and 0.11 ng/ml, respectively. Furthermore, the incidence of an adverse 14-day clinical event in patients with RVD and elevated cTnl was greater (40.7%) than in patients with elevated cTnl or positive RVD alone (0% and 8.3%, respectively) (P〈0.001). Conclusions RVD, RVED/LVED, and cTnl are independent predictors of 14-day clinical outcomes. The patients with RVED/LVED greater than 0.65 展开更多
关键词 pulmonary thromboembolism right ventricular dysfunction cardiac troponin I risk stratification transthoracic echocardiography
原文传递
Microstructural characteristics and aging response of Zn-containing Al-Mg-Si-Cu alloy 被引量:24
3
作者 yuan-hua Cai Cong Wang Ji-shan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2013年第7期659-664,共6页
Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy (OM), field emission scanning el... Al-Mg-Si-Cu alloys with and without Zn addition were fabricated by conventional ingot metallurgy method. The microstructures and properties were investigated using optical microscopy (OM), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), tensile test, hardness test, and electrical conductivity measurement. It is found that the as-cast A1-Mg-Si-Cu-Zn alloy is composed of coarse dendritic grains, long needle-like ~/5-A1FeSi white intermetallics, and Chinese script-like a-A1FeSi compounds. During high temperature homogenization treatment, only harmful needle-like ^-A1FeSi phase undergoes fragmentation and spheroidizing at its tips, and the destruc- tive needle-like 5-phase does not show any morphological and size changes. Phase transitions from ^-A1FeSi to ^-A1FeSi and from 6-A1FeSi to [3-A1FeSi are also not found. Zn addition improves the aging hardening response during the former aging stage and postpones the peak-aged hardness to a long aging time. In T4 condition, Zn addition does not obviously increase the yield strength and decrease the elongation, but it markedly improves paint-bake hardening response during paint-bake cycle. The addition of 0.5wt% Zn can lead to an increment of 99 MPa in yield strength compared with the value of 69 MPa for the alloy without Zn after paint-bake cycle. 展开更多
关键词 aluminum alloys ZINC HARDENING mechanical properties microstructure
下载PDF
Effect of early goal directed therapy on tissue perfusion in patients with septic shock 被引量:19
4
作者 yuan-hua Lu Ling Liu +3 位作者 Xiao-hua Qiu Qin Yu Yi Yang Hai-bo Qiu 《World Journal of Emergency Medicine》 CAS 2013年第2期117-122,共6页
BACKGROUND:This study aimed to observe the effect of early goal directed therapy(EGDT)on tissue perfusion,microcirculation and tissue oxygenation in patients with septic shock.METHODS:Patients with early septic shock(... BACKGROUND:This study aimed to observe the effect of early goal directed therapy(EGDT)on tissue perfusion,microcirculation and tissue oxygenation in patients with septic shock.METHODS:Patients with early septic shock(<24 hours) who had been admitted to the ICU of Zhongda Hospital Affiliated to Southeast University from September 2009 through May 2011 were enrolled(research time:12 months),and they didn't meet the criteria of EGDT.Patients who had one of the following were excluded:stroke,brain injury,other types of shock,severe heart failure,acute myocardial infarction,age below 18 years,pregnancy,end-stage disease,cardiac arrest,extensive burns,oral bleeding,difficulty in opening the mouth,and the onset of septic shock beyond 24 hours.Patients treated with the standard protocol of EGDT were included.Transcutaneous pressure of oxygen and carbon dioxide(PtcO_2,PtcCO_2) were monitored and hemodynamic measurements were obtained.Side-stream dark field(SDF) imaging device was applied to obtain sublingual microcirculation.Hemodynamics,tissue oxygen,and sublingual microcirculation were compared before and after EGDT.If the variable meets the normal distribution,Student's t test was applied.Otherwise,Wilcoxon's rank-sum test was used.Correlation between variables was analyzed with Pearson's product-moment correlation coefficient method.RESULTS:Twenty patients were involved,but one patient wasn't analyzed because he didn't meet the EGDT criteria.PtcO_2 and PtcCO_2 were monitored in 19 patients,of whom sublingual microcirculation was obtained.After EGDT,PtcO_2 increased from 62.7+24.0 mmHg to 78.0±30.9mmHg(P<0.05) and tissue oxygenation index(PtcO_2/FiO_2) was 110.7+60.4 mmHg before EGDT and 141.6±78.2 mmHg after EGDT(P<0.05).The difference between PtcCO_2 and PCO_2 decreased significantly after EGDT(P<0.05).The density of perfused small vessels(PPV) and microcirculatory flow index of small vessels(MFI) tended to increase,but there were no significant differences between them(P>0.05).PtcO_2,PtcO_2/FiO_2,and PtcCO_2 were 展开更多
关键词 Transcutaneous pressure of oxygen Transcutaneous pressure of carbon dioxide MICROCIRCULATION Septic shock EGDT Tissue perfusion Tissue oxygenation Sidestream dark field imaging
下载PDF
Microstructure evolution and phase transformation of traditional cast and spray-formed hypereutectic aluminium-silicon alloys induced by heat treatment 被引量:14
5
作者 Long-gang Hou yuan-hua Cai +1 位作者 hua Cui Ji-shan Zhang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2010年第3期297-306,共10页
Microstructural evolution and phase transformation induced by different heat treatments of the hypereutectic aluminium-silicon alloy, Al-25Si-5Fe-3Cu (wt%, signed as 3C), fabricated by traditional cast (TC) and sp... Microstructural evolution and phase transformation induced by different heat treatments of the hypereutectic aluminium-silicon alloy, Al-25Si-5Fe-3Cu (wt%, signed as 3C), fabricated by traditional cast (TC) and spray forming (SF) processes, were investigated by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy and X-ray diffraction techniques. The results show that A17Cu2Fe phase can be formed and transformed in TC- and SF-3C alloys between 802-813 K and 800-815 K, respectively. The transformation from β-Al5FeSi to δ-Al4FeSi2 phase via peritectic reaction can occur at around 858-870 K and 876-890 K in TC- and SF-3C alloys, respectively. The starting precipitation temperature of δ-Al4FeSi2 phase as the dominant Fe-bearing phase in the TC-3C alloy is 997 K and the exothermic peak about the peritectic transformation of δ-Al4FeSi2→β-Al5FeSi is not detected in the present DSC experiments. Also, the mechanisms of the microstructural evolution and phase transformation are discussed. 展开更多
关键词 hypereutectic Al-Si alloy spray forming CAST microstructure phase transformation
下载PDF
Quantification and timing of porosity evolution in tight sand gas reservoirs:an example from the Middle Jurassic Shaximiao Formation,western Sichuan,China 被引量:14
6
作者 Zheng-Xiang Lü Su-Juan Ye +2 位作者 Xiang Yang Rong Li yuan-hua Qing 《Petroleum Science》 SCIE CAS CSCD 2015年第2期207-217,共11页
The diagenesis and porosity evolution of the Middle Jurassic Shaximiao sandstones were analyzed based on petrographic observations, X-ray diffractometry, scanning electron microscopy observations, carbon and oxygen st... The diagenesis and porosity evolution of the Middle Jurassic Shaximiao sandstones were analyzed based on petrographic observations, X-ray diffractometry, scanning electron microscopy observations, carbon and oxygen stable isotope geochemistry, fluid inclusion mi- crothermometry, and thermal and burial history modeling results. The point count data show that secondary pores (av. 5.5 %) are more abundant than primary pores (av. 3.7 %) and are thus the dominant pore type in the Shaximiao sandstones. Analysis of porosity evolution indicates that alteration of sandstones mainly occurred during two paragenetic stages. Mechanical compaction and cementa- tion by early chlorite, calcite, and quartz typically decrease the depositional porosity (40.9 %) by an average of 37.2 %, leaving porosity of 3.7 % after stage I (〈85 ℃, 175-145 Ma). The original intergranular porosity loss due to compaction is calculated to be 29.3 %, suggesting that mechanical compaction is the most significant diagenetic process in primary porosity destruction. Stage II can be further divided into two sub-stages (Stage IIa and Stage IIb). Stage IIa (85-120 ℃, 145-125 Ma) is characterized by late dissolution, which enhanced porosity by 8.8 %, and the porosity increased from 3.7 % to 12.5 %. During stage IIb (〉120 ℃, 125-0 Ma), the precipitation of late chlorite, calcite, quartz, and kaolinite destroyed 3.3 % porosity, leaving porosity of 9.2 % in the rock today. 展开更多
关键词 DIAGENESIS Porosity evolution -Tight gas sandstones JURASSIC Western Sichuan
下载PDF
N-acetylcysteine protects against cadmium-induced germ cell apoptosis by inhibiting endoplasmic reticulum stress in testes 被引量:10
7
作者 Yan-Li Ji hua Wang Cheng Zhang Ying Zhang Mei Zhao yuan-hua Chen De-Xiang Xu 《Asian Journal of Andrology》 SCIE CAS CSCD 2013年第2期290-296,I0010,共8页
Cadmium (Cd) is a reproductive toxicant that induces germ cell apoptosis in the testes. Previous studies have demonstrated that endoplasmic reticulum (ER) stress is involved in Cd-induced germ cell apoptosis. The ... Cadmium (Cd) is a reproductive toxicant that induces germ cell apoptosis in the testes. Previous studies have demonstrated that endoplasmic reticulum (ER) stress is involved in Cd-induced germ cell apoptosis. The aim of the present study was to investigate the effects of N-acetylcysteine (NAC), an antioxidant, on Cd-induced ER stress and germ cell apoptosis in the testes. Male CD-1 mice were intraperitoneally injected with CdCl2 (2.0 mg kg^-1). As expected, acute Cd exposure induced germ cell apoptosis in the testes, as determined by terminal dUTP nick-end labelling (TUNEL). However, the administration of NAC alleviated Cd-induced germ ceil apoptosis in the testes. Further analysis showed that NAC attenuated the Cd-induced upregulation of testicular glucose-regulated protein 78 (GRP78), an important ER molecular chaperone. Moreover, NAC inhibited the Cd-induced phosphorylation of testicular eukaryotic translation initiation factor 2a (elF2a), a downstream target of the double-stranded RNA-activated kinase-like ER kinase (PERK) pathway. In addition, NAC blocked the Cd-induced activation of testicular X binding protein (XBP)-1, indicating that NAC attenuates the Cd-induced ER stress and the unfolded protein response (UPR). Interestingly, NAC almost completely prevented the Cd-induced elevation of C/EBP homologous protein (CHOP) and phosphorylation of c-Jun N-terminal kinase (.INK), two components of the ER stress-mediated apoptotic pathway. In conclusion, NAC protects against Cd-induced germ cell apoptosis by inhibiting endoplasmic reticulum stress in the testes. 展开更多
关键词 antioxidant apoptosis cadmium endoplasmic reticulum stress N-acetylcysteine (NAC) TESTIS unfolded protein response
下载PDF
Effect of coal resources development and compensation for damage to cultivated land in mining areas 被引量:10
8
作者 LI Yong-feng LIU yuan-hua +1 位作者 DU Zhuan-ping CHEN Jie 《Mining Science and Technology》 EI CAS 2009年第5期620-625,共6页
The exploitation of coal resources inevitably affects, to different degrees, arable land resources and impacts the socio-economic development in mining areas. Therefore it is of great practical importance to probe the... The exploitation of coal resources inevitably affects, to different degrees, arable land resources and impacts the socio-economic development in mining areas. Therefore it is of great practical importance to probe the rules of the effect from coal resource exploration on arable land. Suitable and effective measures to compensate for damaged to and loss of arable land resources should be taken on the basis of carrying out green mining and reducing damage to limited arable land resources. We have used GIS in simulating the effect of coal resource exploration on arable land. In light of our simulation of the space-time spectrum, the effect is analyzed. Given the socio-economic development conditions of a mining area, specified rational amounts and opportunities for compensation to arable land in mining areas are explored. Finally, from a policy perspective, relevant proposals for rational arable land resource compensation are proposed to facilitate the coordinated development between coal resource exploitation and socio-economy development in mining areas. 展开更多
关键词 coal resource exploitation arable land in mining areas COMPENSATION
下载PDF
Effects of Ni doping contents on photocatalytic activity of B-BiVO_4 synthesized through sol-gel and impregnation two-step method 被引量:10
9
作者 Min WANG Guang-jun YANG +4 位作者 Mei-yan YOU yuan-hua XIE You-zhao WANG Jin HAN Tong ZHU 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2017年第9期2022-2030,共9页
To enhance the photocatalytic activity of B-BiVO4,Ni-doped B?BiVO4photocatalyst(Ni-B-BiVO4)was synthesized through sol-gel and impregnation method.The photocatalysts were characterized by XPS,XRD,SEM,EDS,BET and UV-Vi... To enhance the photocatalytic activity of B-BiVO4,Ni-doped B?BiVO4photocatalyst(Ni-B-BiVO4)was synthesized through sol-gel and impregnation method.The photocatalysts were characterized by XPS,XRD,SEM,EDS,BET and UV-Vis DRS techniques.The results showed that single or double doping did not change the crystalline structure and morphology,but the particle size decreased with Ni doping.The band gap energy absorption edge of Ni-B-BiVO4shifted to a longer wavelength compared with undoped,B or Ni single doped BiVO4.More V4+and surface hydroxyl oxygen were observed in BiVO4after Ni-B co-doping.When the optimal mass fraction of Ni is0.30%,the degradation rate of MO in50min is95%for0.3Ni-B-BiVO4sample which also can effectively degrade methyl blue(MB),acid orange(AOII)II and rhodamine B(RhB).The enhanced photocatalytic activity is attributed to the synergistic effects of B and Ni doping. 展开更多
关键词 CO-DOPING Ni doping BIVO4 PHOTOCATALYST sol.gel method impregnation method
下载PDF
Effects of simvastatin on cigarette smoke extract induced tissue-type plasminogen activator and plasminogen activator inhibitor-1 expression in human umbilical vein endothelial cells 被引量:10
10
作者 HU Xiao-yun MA Yu-hui +1 位作者 WANG Chen YANG yuan-hua 《Chinese Medical Journal》 SCIE CAS CSCD 2009年第19期2380-2385,共6页
Background Cigarette smoking has an influence on both arterial-type and venous-type thrombosis. However, little is known about the direct effect of cigarette smoke extract (CSE) on fibrinolytic activity of human umb... Background Cigarette smoking has an influence on both arterial-type and venous-type thrombosis. However, little is known about the direct effect of cigarette smoke extract (CSE) on fibrinolytic activity of human umbilical vein endothelial cells (HUVECs). Most recently, simvastatin has been marked in its effect on endothelial cells protection and anticoagulation. In this study, the effect of CSE on the expression of tissue-type plasminogen activator (t-PA) and plasminogen activator inhibitor-l(PAl-1) in HUVECs was addressed. The role of simvastatin in CSE-induced fibrinolytic activity changes was investigated as well. Methods The fourth to fifth generation of HUVECs were incubated respectively with 0, 5%, 10% and 20% CSE for 6 hours or exposed to 5% CSE for 0, 4, 6, 8, 12, 24 hours to determine the expression changes of t-PA and PAl-1 protein. Meanwhile, cells were also accordingly exposed either to 5% CSE alone or simvastatin pre-treated and 5% CSE for 24 hours to assess the role of simvastatin in CSE-induced t-PA and PAl-1 protein and mRNA expression in HUVECs. RT-PCR and ELISA techniques were used for detecting the t-PA or PAl-1 mRNA and protein. Results After 6-hour exposure to CSE, the expression levels of t-PA protein in 10% and 20% CSE-treated groups reduced significantly ((0.0365±0.0083) ng/ml, (0.0255±0.0087) ng/ml) when compared with that of control group ((0.0660±0.0120) ng/ml) (P 〈0.05). In contrast, the levels of PAl-1 protein in 5%, 10% and 20% CSE-treated groups increased remarkably ((13.3225±0.5680) ng/ml, (14.2675±1.5380) ng/ml, (14.4292±1.6230) ng/ml) when compared with that of control group ((8.5193_±0.7537)ng/ml) (P〈0.05). After stimulation with 5% CSE for 0, 4, 6, 8, 12, 24 hours, the levels of PAl-1 protein increased over time and reached the peak at 24 hours ((14.6400±1.0651) ng/ml), which was significantly higher than that of control group ((12.0656±0.6148) ng/ml) (P 〈0.05). Additionally, 展开更多
关键词 cigarette smoke extract SIMVASTATIN tissue-type plasminogen activator plasminogen activator inhibitor-1 human umbilical vascular endothelial cells
原文传递
Quasi-cyclic LDPC codes with high-rate and low error floor based on Euclidean geometries 被引量:9
11
作者 LIU yuan-hua ZHANG Mei-ling FAN Jiu-lun 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2012年第2期96-99,共4页
An improved Euclidean geometry approach to design quasi-cyclic (QC) Low-density parity-check (LDPC) codes with high-rate and low error floor is presented. The constructed QC-LDPC codes with high-rate have lower er... An improved Euclidean geometry approach to design quasi-cyclic (QC) Low-density parity-check (LDPC) codes with high-rate and low error floor is presented. The constructed QC-LDPC codes with high-rate have lower error floor than the original codes. The distribution of the minimum weight codeword is analyzed, and a sufficient existence condition of the minimum weight codeword is found. Simulations show that a lot of QC-LDPC codes with lower error floor can be designed by reducing the number of the minimum weight codewords satisfying this sufficient condition. 展开更多
关键词 low-density parity-check codes quasi-cyclic Euclidean geometry
原文传递
Electrical and thermal transport behaviours of high-entropy perovskite thermoelectric oxides 被引量:9
12
作者 Yunpeng Zheng Mingchu Zou +4 位作者 Wenyu Zhang Di Yi Jinle Lan Ce-Wen Nan yuan-hua Lin 《Journal of Advanced Ceramics》 SCIE CAS CSCD 2021年第2期377-384,共8页
Oxide-based ceramics could be promising thermoelectric materials because of their thermal and chemical stability at high temperature.However,their mediocre electrical conductivity or high thermal conductivity is still... Oxide-based ceramics could be promising thermoelectric materials because of their thermal and chemical stability at high temperature.However,their mediocre electrical conductivity or high thermal conductivity is still a challenge for the use in commercial devices.Here,we report significantly suppressed thermal conductivity in SrTiO_(3)-based thermoelectric ceramics via high-entropy strategy for the first time,and optimized electrical conductivity by defect engineering.In high-entropy(Ca_(0.2)Sr_(0.2)Ba_(0.2)Pb_(0.2)La_(0.2))TiO_(3)bulks,the minimum thermal conductivity can be 1.17 W/(m·K)at 923 K,which should be ascribed to the large lattice distortion and the huge mass fluctuation effect.The power factor can reach about 295μW/(m·K^(2))by inducing oxygen vacancies.Finally,the ZT value of 0.2 can be realized at 873 K in this bulk sample.This approach proposed a new concept of high entropy into thermoelectric oxides,which could be generalized for designing high-performance thermoelectric oxides with low thermal conductivity. 展开更多
关键词 high entropy thermoelectric oxides thermal conductivity electrical conductivity oxygen vacancy
原文传递
BiCuSeO as state-of-the-art thermoelectric materials for energy conversion:from thin films to bulks 被引量:8
13
作者 Rui Liu Xing Tan +5 位作者 Yao-Chun Liu Guang-Kun Ren Jin-Le Lan Zhi-Fang Zhou Ce-Wen Nan yuan-hua Lin 《Rare Metals》 SCIE EI CAS CSCD 2018年第4期259-273,共15页
BiCuSeO-based thermoelectric material has attracted great attention as state-of-the-art thermoelectric materials since it was first reported in 2010. In this review, we update the studies on the BiCuSeO thin films fir... BiCuSeO-based thermoelectric material has attracted great attention as state-of-the-art thermoelectric materials since it was first reported in 2010. In this review, we update the studies on the BiCuSeO thin films first. Then, we focus on the most recent progress of multiple approaches that enhance the thermoelectric performance including advanced synthesized technologies, notable mechanisms for higher power factor (optimizing carrier concentration, carrier mobility, Seebeck coefficient) and doping effects predicted by calculation. And finally, aiming at further enhancing the performance of these materials and ultimately commercial application, we give a brief discussion on the urgent issues to which should be paid close attention. 展开更多
关键词 BiCuSeO State-of-the-art thermoelectricmaterials Thin films Bulks
原文传递
Pollen and Phytolith Analyses of Ancient Paddy Fields at Chuodun Site, the Yangtze River Delta 被引量:8
14
作者 LI Chun-Hai ZHANG Gang-Ya +6 位作者 YANG Lin-Zhang LIN Xian-Gui HU Zheng-Yi DONG yuan-hua CAO Zhi-Hong ZHENG Yun-Fei DING Jin-Long 《Pedosphere》 SCIE CAS CSCD 2007年第2期209-218,共10页
A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta.... A number of paddy fields pertaining to the Majiabang Cultures (5500-3800 years BC) were discovered during the archaeological excavations that were carried out since 1998 at the Chuodun site in the Yangtze River Delta. The pollen and phytolith analyses of two soil profiles from the northeastern part of this site were carried out to trace the agricultural practices of the Neolithic period. The phytolith results showed that rice domestication in the Yangtze River Delta could be traced back to as early as the Majiabang Culture. The pollen assemblage also revealed low levels of aquatic species, similar to that in modern paddy fields. This finding suggested that humans might have removed weeds for rice cultivation during the Neolithic period. Thus, pollen analysis in association with phytolith analysis was a promising method for identifying ancient paddy fields. 展开更多
关键词 ancient paddy fields Neolithic period pollen analysis phytolith analysis Yangtze River Delta
下载PDF
Neuroprotective effects of neural stem cells pretreated with neuregulin1β on PC12 cells exposed to oxygen-glucose deprivation/reoxygenation 被引量:3
15
作者 Qiu-Yue Zhai yuan-hua Ye +4 位作者 Yu-Qian Ren Zhen-hua Song Ke-Li Ge Bao-He Cheng Yun-Liang Guo 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第3期618-625,共8页
Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion injury.However,NSCs are difficult to obtain owing to ethical limitations.... Studies on ischemia/reperfusion(I/R)injury suggest that exogenous neural stem cells(NSCs)are ideal candidates for stem cell therapy reperfusion injury.However,NSCs are difficult to obtain owing to ethical limitations.In addition,the survival,differentiation,and proliferation rates of transplanted exogenous NSCs are low,which limit their clinical application.Our previous study showed that neuregulin1β(NRG1β)alleviated cerebral I/R injury in rats.In this study,we aimed to induce human umbilical cord mesenchymal stem cells into NSCs and investigate the improvement effect and mechanism of NSCs pretreated with 10 nM NRG1βon PC12 cells injured by oxygen-glucose deprivation/reoxygenation(OGD/R).Our results found that 5 and 10 nM NRG1βpromoted the generation and proliferation of NSCs.Co-culture of NSCs and PC12 cells under condition of OGD/R showed that pretreatment of NSCs with NRG1βimproved the level of reactive oxygen species,malondialdehyde,glutathione,superoxide dismutase,nicotinamide adenine dinucleotide phosphate,and nuclear factor erythroid 2-related factor 2(Nrf2)and mitochondrial damage in injured PC12 cells;these indexes are related to ferroptosis.Research has reported that p53 and solute carrier family 7 member 11(SLC7A11)play vital roles in ferroptosis caused by cerebral I/R injury.Our data show that the expression of p53 was increased and the level of glutathione peroxidase 4(GPX4)was decreased after RNA interference-mediated knockdown of SLC7A11 in PC12 cells,but this change was alleviated after co-culturing NSCs with damaged PC12 cells.These findings suggest that NSCs pretreated with NRG1βexhibited neuroprotective effects on PC12 cells subjected to OGD/R through influencing the level of ferroptosis regulated by p53/SLC7A11/GPX4 pathway. 展开更多
关键词 ferroptosis P53 SLC7A11 GPX4 human umbilical cord-mesenchymal stem cells neural stem cells neuregulin1β NEUROPROTECTION oxygen-glucose deprivation/reoxygenation PC12 cell
下载PDF
C5a/C5a R pathway is essential for up-regulating Sph K1 expression through p38-MAPK activation in acute liver failure 被引量:7
16
作者 Yan-Chang Lei Chun-Lei Lu +4 位作者 Ling Chen Ke Ge Ling-Ling Yang Wen Li yuan-hua Wu 《World Journal of Gastroenterology》 SCIE CAS 2016年第46期10148-10157,共10页
AIM To investigate the role of the complement 5a(C5a)/C5 a receptor(C5a R) pathway in the pathogenesis of acute liver failure(ALF) in a mouse model.METHODS BALB/c mice were randomly assigned to different groups, and i... AIM To investigate the role of the complement 5a(C5a)/C5 a receptor(C5a R) pathway in the pathogenesis of acute liver failure(ALF) in a mouse model.METHODS BALB/c mice were randomly assigned to different groups, and intraperitoneal injections of lipopolysaccharide(LPS)/D-galactosamine(D-Gal N)(600 mg/kg and 10 μg/kg) were used to induce ALF. The KaplanMeier method was used for survival analysis. Serum alanine aminotransferase(ALT) levels, at different time points within a 1-wk period, were detected with a biochemistry analyzer. Pathological examination of liver tissue was performed 36 h after ALF induction. Serum complement 5(C5), C5 a, tumor necrosis factor-α(TNF-α), interleukin(IL)-1β, IL-6, high-mobility group protein B1(HMGB1) and sphingosine-1-phosphatelevels were detected by enzyme-linked immunosorbant assay. Hepatic morphological changes at 36 h after ALF induction were assessed by hematoxylin and eosin staining. Expression of C5 a R, sphingosine kinase 1(Sph K1), p38-MAPK and p-p38-MAPK in liver tissue, peripheral blood mononuclear cells(PBMCs) and peritoneal exudative macrophages(PEMs) of mice or RAW 264.7 cells was analyzed by western blotting. C5 a R m RNA levels were detected by quantitative real-time PCR.RESULTS Activation of C5 and up-regulation of C5 a R were observed in liver tissue and PBMCs of mice with ALF. Blockade of C5 a R with a C5 a R antagonist(C5a Ra C5 a Ra) significantly reduced the levels of serum ALT, inflammatory cytokines(TNF-α, IL-1β and IL-6) and HMGB1, as well as the liver tissue damage, but increased the survival rates(P < 0.01 for all). Blockade of C5 a R decreased Sph K1 expression in both liver tissue and PBMCs significantly at 0.5 h after ALF induction. C5 a Ra pretreatment significantly downregulated the phosphorylation of p38-MAPK in liver tissues of ALF mice and C5 a stimulated PEMs or RAW 264.7 cells. Moreover, inhibition of p38-MAPK activity with SB203580 reduced Sph K1 protein production significantly in PEMs after C5 a stimulation.CONCLUSION The C5a/C5 a R path 展开更多
关键词 Acute liver failure C5a/C5a R P38-MAPK Sphingosine kinase 1
下载PDF
Endovascular Catheter-guided Forceps Biopsy for the Diagnosis of Suspected Pulmonary Artery Sarcoma: A Preliminary Study of Eight Cases 被引量:7
17
作者 Wan-Mu Xie Zhen-Guo Zhai +3 位作者 Le-Feng Wang Jun Wan yuan-hua Yang Chen Wang 《Chinese Medical Journal》 SCIE CAS CSCD 2016年第18期2246-2249,共4页
Pulmonary artery sarcoma (PAS) is a rare malignant tumor that originates from the pulmonary artery (PA) with a poor prognosis,Early diagnosis and radical surgical resection offer the only chance for survival As mo... Pulmonary artery sarcoma (PAS) is a rare malignant tumor that originates from the pulmonary artery (PA) with a poor prognosis,Early diagnosis and radical surgical resection offer the only chance for survival As most PA sarcomas involve the PA trunk, making a preoperative histopathological diagnosis is quite difficult. So far, most PAS cases were reported with diagnosis made either at autopsy or intraoperatively with frozen sections. 展开更多
关键词 BIOPSY Histopathological Diagnosis Pulmonary Artery Sarcoma
原文传递
Investigating the Mechanism of Qu Du Qiang Fei 1 Hao Fang Formula against Coronavirus Disease 2019 Based on Network Pharmacology Method
18
作者 yuan-hua Wang He-Yang Zhou +4 位作者 Jin-Yun Ma Gui-Qing Ding hua Yu Yong-Sheng Jin Xiao-Dong Cheng 《World Journal of Traditional Chinese Medicine》 CAS CSCD 2024年第1期93-103,共11页
Objective:Qu Du Qiang Fei 1 Hao Fang(QDQF1)is a novel Chinese herbal medicine formula used to treat coronavirus disease 2019(COVID-19).However,the pharmacological mechanisms of action of QDQF1 remain unclear.The objec... Objective:Qu Du Qiang Fei 1 Hao Fang(QDQF1)is a novel Chinese herbal medicine formula used to treat coronavirus disease 2019(COVID-19).However,the pharmacological mechanisms of action of QDQF1 remain unclear.The objective of this study was to identify the effective ingredients and biological targets of QDQF1 for COVID-19 treatment.Materials and Methods:The effective ingredients and mechanisms of action of QDQF1 were analyzed by using network pharmacology methods,which included an analysis of the effective ingredients and corresponding targets,COVID-19-related target acquisition,compound-target network analyses,protein-protein interaction network analysis,Kyoto Encyclopedia of Genes and Genomes(KEGG)and Gene Ontology(GO)enrichment analyses,and molecular docking studies.Results:In total,288 effective QDQF1 ingredients were identified.We identified 51 core targets from the 148 targets through an overlap between putative QDQF1 targets and COVID-19-related targets.Six key components,including formononetin,kaempferol,luteolin,naringenin,quercetin,and wogonin were identified through component-target network analyses.GO functional enrichment analysis of the core targets revealed 1296 items,while KEGG pathway enrichment analysis identified 148 signaling pathways.Nine central targets(CCL2,CXCL8,IL1B,IL6,MAPK1,MAPK3,MAPK8,STAT3,and TNF)related to the COVID-19 pathway were identified in the KEGG pathway enrichment analysis.Furthermore,molecular docking analysis suggested that the docking scores of the six key components to the nine central targets were better than those to remdesivir.Conclusions:QDQF1 may regulate multiple immune-and inflammation-related targets to inhibit the progression of severe acute respiratory syndrome coronavirus 2,and thus,may be suitable for the treatment of COVID-19. 展开更多
关键词 Coronavirus disease 2019 molecular docking molecular mechanism network pharmacology Qu Du Qiang Fei 1 Hao Fang formula
原文传递
Increasing nitrogen absorption and assimilation ability under mixed NO_(3)^(–)and NH_(4)^(+) supply is a driver to promote growth of maize seedlings 被引量:2
19
作者 WANG Peng WANG Cheng-dong +5 位作者 WANG Xiao-lin WU yuan-hua ZHANG Yan SUN Yan-guo SHI Yi MI Guo-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2023年第6期1896-1908,共13页
Compared with sole nitrate (NO_(3)^(-)) or sole ammonium (NH_(4)^(+)) supply,mixed nitrogen (N) supply may promote growth of maize seedlings.Previous study suggested that mixed N supply not only increased photosynthes... Compared with sole nitrate (NO_(3)^(-)) or sole ammonium (NH_(4)^(+)) supply,mixed nitrogen (N) supply may promote growth of maize seedlings.Previous study suggested that mixed N supply not only increased photosynthesis rate,but also enhanced leaf growth by increasing auxin synthesis to build a large sink for C and N utilization.However,whether this process depends on N absorption is unknown.Here,maize seedlings were grown hydroponically with three N forms (NO_(3)^(-)only,75/25 NO_(3)^(-)/NH_(4)^(+) and NH_(4)^(+) only).The study results suggested that maize growth rate and N content of shoots under mixed N supply was little different to that under sole NO_(3)^(-)supply at 0–3 d,but was higher than under sole NO_(3)^(-)supply at 6–9 d.^(15)N influx rate under mixed N supply was greater than under sole NO_(3)^(-) or NH_(4)^(+) supply at 6–9 d,although NO_(3)^(-) and NH_(4)^(+) influx under mixed N supply were reduced compared to sole NO_(3)^(-) and NH_(4)^(+) supply,respectively.qRT-PCR determination suggested that the increased N absorption under mixed N supply may be related to the higher expression of NO_(3)^(-) transporters in roots,such as ZmNRT1.1A,ZmNRT1.1B,ZmNRT1.1C,ZmNRT1.2 and ZmNRT1.3,or NH_(4)^(+) absorption transporters,such as Zm AMT1.1A,especially the latter.Furthermore,plants had higher nitrate reductase (NR)glutamine synthase (GS) activity and amino acid content under mixed N supply than when under sole NO_(3)^(-) supply.The experiments with inhibitors of NR reductase and GS synthase further confirmed that N assimilation ability under mixed N supply was necessary to promote maize growth,especially for the reduction of NO_(3)^(-) by NR reductase.This research suggested that the increased processes of NO_(3)^(-)and NH_(4)^(+) assimilation by improving N-absorption ability of roots under mixed N supply may be the main driving force to increase maize growth. 展开更多
关键词 MAIZE NO_(3)^(-)/NH_(4)^(+)ratio N absorption N assimilation plant growth
下载PDF
Loss of heterozygosity for chromosomes 16q in Wilms tumors predicts outcomes:A meta-analysis
20
作者 yuan-hua Song Wen-Ling Li +2 位作者 Zhen Yang Yan Gao Zhi-Ping Feng 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第5期2159-2167,共9页
BACKGROUND The research findings suggest that the prognosis of children with Wilms tumor(WT)is affected by various factors.Some scholars have indicated that loss of heterozygosity(LOH)on chromosome 16q is associated w... BACKGROUND The research findings suggest that the prognosis of children with Wilms tumor(WT)is affected by various factors.Some scholars have indicated that loss of heterozygosity(LOH)on chromosome 16q is associated with a poor prognosis in patients with WT.AIM To further elucidate this relationship,we conducted a meta-analysis.METHODS This meta-analysis was registered in INPLASY(INPLASY2023100060).We systematically searched databases including Embase,PubMed,Web of Science,Cochrane,and Google Scholar up to May 31,2020,for randomized trials reporting any intrapartum fetal surveillance approach.The meta-analysis was performed within a frequentist framework,and the quality and network inconsistency of trials were assessed.Odds ratios and 95%CIs were calculated to report the relationship between event-free survival and 16q LOH in patients with WT.RESULTS Eleven cohort studies were included in this meta-analysis to estimate the relationship between event-free survival and 16q LOH in patients with WT(I^(2)=25%,P<0.001).As expected,16q LOH can serve as an effective predictor of eventfree survival in patients with WT(risk ratio=1.95,95%CI:1.52–2.49,P<0.001).CONCLUSION In pediatric patients with WT,there exists a partial correlation between 16q LOH and an unfavorable treatment prognosis.Clinical detection of 16q chromosome LOH warrants increased attention to the patient’s prognosis. 展开更多
关键词 Loss of heterozygosity Wilms tumor Survival time Chromosomes 16q
下载PDF
上一页 1 2 97 下一页 到第
使用帮助 返回顶部