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Correlation of Inferior Vena Cava Respiratory Variability Index with Central Venous Pressure and Hemodynamic Parameters in Ventilated Pigs with Septic Shock 被引量:3
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作者 LIU Xiao Lei TAO Yong Kang +5 位作者 YAN Sheng Tao QI Zhi Wei LU Hai Tao WANG Hai Feng GU Cheng Dong ZHANG Guo Qiang 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第6期500-503,共4页
Septic shock is a common critical condition, for which effective early fluid resuscitation is the therapeutic focus. According to the 2008 international guidelines for management of severe sepsis and septic shock, res... Septic shock is a common critical condition, for which effective early fluid resuscitation is the therapeutic focus. According to the 2008 international guidelines for management of severe sepsis and septic shock, resuscitation should achieve a central venous pressure (CVP) of 8-12 mmHg within the first 6 h. However, it is still uncertain about the sensitivity and specificity of CVP in reflecting the cardiac preload. Ultrasonography is a simple, rapid, non-invasive, and repeatable method for the measurement of sensitivity and specificity of CVP and has thus gradually attracted the increasing attention of physicians. It was reported that ultrasonography can show the inferior vena cava diameter, respiratory variability index, and blood volume in patients with sepsis or heart failure. 展开更多
关键词 CVP SVV Correlation of Inferior Vena Cava Respiratory Variability index with central Venous Pressure and Hemodynamic Parameters in Ventilated Pigs with Septic Shock
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Neotectonics of Tabas Area, Central Iran by Index of Active Tectonics (IAT) 被引量:1
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作者 Elahe Javadi Mosavi Mehran Arian +1 位作者 Manochehr Ghorshi Mohammad Nazemi 《Open Journal of Geology》 2015年第4期209-223,共15页
In this research, Tabas area, which is located in central Iran, was selected as the study area and three geomorphic indices were calculated for its structural fronts. Through averaging these three indices, we obtained... In this research, Tabas area, which is located in central Iran, was selected as the study area and three geomorphic indices were calculated for its structural fronts. Through averaging these three indices, we obtained index of active tectonics (IAT). The values of the index were divided into classes to define the degree of active tectonics. Therefore, relative tectonic activity was calculated and their values were classified and analyzed in two groups. Regions were identified as high and moderate levels. In analyzing data and combining them with tectonic setting, the results were often associated and justified with regional geology. Our results show that the highest value is located along Shoutori fault, which shows 2 class of relative tectonic activity (high level). Also, moderate values are located along Ereshk, Ezmeighan and Jamal faults (moderate level). According to these results, Shoutori fault is the most active fault in the study area and this situation is compatible with its position as a mountain front fault. 展开更多
关键词 ACTIVE TECTONICS index Tabas central Iran
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Investigation of the Fiber Central Dip Refractive Index Profile Using Laser-Lens Fiber Interferometer
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作者 Hatem El-Ghandoor Hatem El-Hennawi Fouad EI-Diasty Mona A. Soliman 《材料科学与工程(中英文B版)》 2011年第2期148-156,共9页
关键词 光纤折射率 光纤干涉 透镜光纤 中央 激光 光学纤维 折射率分布 干扰模式
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Nitroglycerin reduces augmentation index and central blood pressure independent of effects on cardiac preload
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作者 Mike Saddon Karen McNeil Philip Chowienczyk 《Journal of Pharmaceutical Analysis》 SCIE CAS 2009年第2期114-119,共6页
Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compare... Objective To determine whether reduction in central pressure augmentation and central systolic blood pressure by nitroglycerine (NTG) results from effects on pre-load or is due to arterial dilation. Methods We compared effects of NTG with those of lower body negative pressure (LBNP). Hemodynamic measurements were made at rest,during LBNP (10,20 and 30 mmHg,each for 15 min) and after NTG (10,30 and 100 μg/min,each dose for 15 min) in ten healthy volunteers. Cardiac pre-load,stroke volume and cardiac output were assessed by echocardiography. Central pressure augmentation and central systolic pressure were obtained by radial tonometry using a transfer function. Results LBNP (20 mmHg) and NTG (30 μg/min) reduced pre-load (as measured by the peak velocity of the S wave in the superior vena cava) to a similar degree [by (26.8±3.8)% and (23.9±3.4)%,respectively]. Compared to LBNP,NTG reduced systemic vascular resistance [by (32.9±7.5)%,P<0.01],decreased peripheral and central pressure augmentation [by (20.8±3.4)% units and (12.9±2.9)% units,respectively,each P<0.01]. Conclusion These results suggest that a reduction in pre-load does not explain reduction in pressure augmentation and central systolic blood pressure by NTG and that these effects are mediated through arterial dilation. 展开更多
关键词 augmentation index central blood pressure NITROGLYCERINE cardiac preload lower body negative pressure
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Central retinal artery resistive index and optical coherence tomography in assessment of glaucoma progression 被引量:2
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作者 Ahmed F.Abdel Ghany Samer M.Botros Tamer M.El-Raggal 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2015年第2期305-309,共5页
AIM: To assess the relation between central retinal artery(CRA) resistive index(RI) and retinal nerve fiber thickness measured by optical coherence tomography(OCT) in assessment of disease progress in cases of open an... AIM: To assess the relation between central retinal artery(CRA) resistive index(RI) and retinal nerve fiber thickness measured by optical coherence tomography(OCT) in assessment of disease progress in cases of open angle glaucoma.METHODS: Twenty-three patients with diagnosed open angle glaucoma were included in this study. They were examined by colored duplex ultrasonography of CRA with estimation of RI of CRA and ophthalmic artery(OA)with estimation of CRA/OA RI ratio as well as OCT measurement of the average retinal nerve fiber layer(RNFL) thickness in order to assess the disease progress.RESULTS: There was strong inverse relation between the increased RI in CRA as well as the increased CRA/OA RI ratio and the decrease in average RNFL thickness in cases of open angle glaucoma.CONCLUSION: Assessment of CRA RI can indirectly assess the vascular changes associated with glaucoma and can assess the degree of retinal atrophy helping in evaluating prognosis thus guiding the choice of treatment. 展开更多
关键词 GLAUCOMA optical coherence tomography central retinal artery duplex ophthalmic artery resistive index
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中亚干旱区植被NDVI时空变化及其区域对比研究
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作者 张汝菡 宫雨生 谈明洪 《环境科学研究》 北大核心 2025年第1期90-100,共11页
植被在生态系统中扮演着重要的角色,归一化植被指数(Normalized Difference Vegetation Index,NDVI)是反映植被变化的重要指标。为阐明中亚干旱区(中亚五国和中国新疆地区)植被NDVI时空演变规律及其影响因素的差异,本研究基于谷歌地球引... 植被在生态系统中扮演着重要的角色,归一化植被指数(Normalized Difference Vegetation Index,NDVI)是反映植被变化的重要指标。为阐明中亚干旱区(中亚五国和中国新疆地区)植被NDVI时空演变规律及其影响因素的差异,本研究基于谷歌地球引擎(Google Earth Engine,GEE),利用2000−2020年植被生长季间MODIS NDVI产品计算逐年平均归一化植被指数(NDVI),采用Sen′s斜率、Mann-Kendall检验,分析中亚干旱区植被NDVI的时空变化;同时结合遥感数据、气象数据和土地利用等数据,构建多元线性回归模型,探索影响NDVI变化的驱动因素。结果表明:①2000−2020年中亚干旱区植被NDVI整体上呈现波动上升趋势,中国新疆地区植被NDVI整体增长速率为2.9×10^(−3)a^(−1),远高于中亚五国总体增长速率(0.6×10^(−3)a^(−1))。②从NDVI变化空间分布来看,中亚五国植被变化趋势空间分布较为分散,植被NDVI改善区域面积占比为25.9%,退化区域面积占比为8.78%;中国新疆地区植被变化呈现出明显的空间集聚效应,改善区域集中在绿洲和主要农业区,植被改善区域面积占比为37.72%,植被退化区域面积仅占0.46%。③植被NDVI受到气候、地形及人类活动要素的多重影响。气温升高抑制中亚干旱区植被生长,降水量增加利于植被生长,高程显著影响植被生长,人类合理利用土地及灌溉设施投入对于植被恢复具有积极作用。研究显示,中亚五国与中国新疆地区植被变化存在明显差异,中国新疆地区植被改善情况明显优于中亚五国。植被NDVI变化受到自然因素和人类活动共同影响,需要综合考虑区域异质性与多重影响因素的协同作用。 展开更多
关键词 中亚干旱区 归一化植被指数(NDVI) 区域差异 时空动态 谷歌地球引擎(GEE)
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Low-carbon economic development in Central Asia based on LMDI decomposition and comparative decoupling analyses 被引量:5
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作者 LI Jiaxiu CHEN Yaning +1 位作者 LI Zhi HUANG Xiaotao 《Journal of Arid Land》 SCIE CSCD 2019年第4期513-524,共12页
Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilizatio... Low-carbon economic development is a strategy that is emerging in response to global climate change. Being the third-largest energy base in the world, Central Asia should adopt rational and efficient energy utilization to achieve the sustainable economic development. In this study, the logarithmic mean Divisia index(LMDI) decomposition method was used to explore the influence factors of CO2 emissions in Central Asia(including Kazakhstan, Uzbekistan, Kyrgyzstan, Tajikistan and Turkmenistan) during the period 1992–2014. Moreover, decoupling elasticity and decoupling index based on the LMDI decomposition results were employed to explore the relationship between economic growth and CO2 emissions during the study period. Our results show that the total CO2 emissions decreased during the period 1992–1998, influenced by the collapse of the Soviet Union in 1991 and the subsequent financial crisis. After 1998, the total CO2 emissions started to increase slowly along with the economic growth after the market economic reform. Energy-related CO2 emissions increased in Central Asia, mainly driven by economic activity effect and population effect, while energy intensity effect and energy carbon structure effect were the primary factors inhibiting CO2 emissions. The contribution percentages of these four factors(economic activity effect, population effect, energy intensity effect and energy carbon structure effect) to the total CO2 emissions were 11.80%, 39.08%, –44.82% and –4.32%, respectively, during the study period. Kazakhstan, Uzbekistan and Turkmenistan released great quantities of CO2 with the annual average emissions of 189.69×106, 45.55×106 and 115.38×106 t, respectively. In fact, their economic developments depended on high-carbon energies. The decoupling indices clarified the relationship between CO2 emissions and economic growth, highlighting the occurrence of a ’’weak decoupling’’ between these two variables in Central Asia. In conclusion, our results indicate that CO2 emissions are still not completely decoupled from economic growth in Central Asia. Based on these results, we suggest four key policy suggestions in this paper to help Central Asia to reduce CO2 emissions and build a resource-conserving and environment-friendly society. 展开更多
关键词 energy-related CO2 emissions low-carbon ECONOMY LMDI DECOMPOSITION DECOUPLING ELASTICITY DECOUPLING index central ASIA
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THE UNEVEN DEVELOPMENT AND SPATIAL DIFFUSION OF CHINESE CENTRAL CITIES
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作者 宁越敏 严重敏 《Chinese Geographical Science》 SCIE CSCD 1994年第2期119-128,共10页
THE UNEVEN DEVELOPMENT AND SPATIAL DIFFUSION OF CHINESE CENTRAL CITIES NingYueAnn(宁越敏);YanZhongmin(严重敏)(TheI... THE UNEVEN DEVELOPMENT AND SPATIAL DIFFUSION OF CHINESE CENTRAL CITIES NingYueAnn(宁越敏);YanZhongmin(严重敏)(TheInstituteofGeograp... 展开更多
关键词 central CITIES centralITY index uneven development SPATIAL DIFFUSION
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Pathologic features and clinical outcome of central neurocytoma:analysis of 15 cases 被引量:6
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作者 Yu Li Xiu-Feng Ye +2 位作者 Guo Qian Yu Yin Qian-Guan Pan 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2012年第4期284-290,共7页
Objective: To get better recognition of central neurocytoma and diminish misdiagnosis. Methods: A retrospective review identified 15 cases of central neurocytoma. All cases of central neurocytoma were analyzed for t... Objective: To get better recognition of central neurocytoma and diminish misdiagnosis. Methods: A retrospective review identified 15 cases of central neurocytoma. All cases of central neurocytoma were analyzed for their clinical symptoms, pathologic changes, immunohistochemical staining, prognosis and differential diagnosis. Clinical follow up was performed. Results: There were 8 males and 7 females aged 10-64 years (median 32.93 years). The most common presenting symptoms were those related to increased intracranial pressure (ICP), including headache (100%), papilledema (93 %) and vomiting (80%). All tumors were located in the ventricular system. The tumors were composed of uniform cells with round nuclei and a fine chromatin pattern, and in some areas, small cells with perinuclear halo could be seen. In particular, the anuclear areas may have a fine fibrillary matrix (neuropil). Nuclear atypia and vascular proliferation appeared in two cases, respectively. Focal necrosis could be seen in one case. Immunohistochemical findings included expression of synaptophysin (15/15), neuron specific enolase (12/15) and glial fibrillary acidic protein (GFAP) (3/15). MIB-1 proliferation index ranged from 0.8- 12.5%, and was more than 2% in 3 of 15 cases assessed. Follow-up information of 11 patients was available. Conclusions: Central neurocytoma has a favorable prognosis in general, but in some cases, the clinical course could be aggressive. Increase of GFAP positivity, proliferation index and vascular proliferation might suggest a more malignant process. 展开更多
关键词 central neurocytoma HISTOPATHOLOGY IMMUNOHISTOCHEMISTRY PROLIFERATION MIB-1 labeling index
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Independent Relationship between Body Mass Index and LH Peak Value of GnRH Stimulation Test in ICPP Girls: A Cross-sectional Study 被引量:4
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作者 赵悦 侯凌 +3 位作者 高洪杰 詹迪 张偲 罗小平 《Journal of Huazhong University of Science and Technology(Medical Sciences)》 SCIE CAS 2017年第4期556-562,共7页
The effect of obesity on idiopathic central precocious puberty(ICPP) girls is still under discussion. The relationship between body mass index(BMI) and sexual hormone levels of gonadotropin-releasing hormone(GnRH... The effect of obesity on idiopathic central precocious puberty(ICPP) girls is still under discussion. The relationship between body mass index(BMI) and sexual hormone levels of gonadotropin-releasing hormone(GnRH) stimulation test in ICPP girls is controversial and the underlying mechanism is unclear. This study aims to further explore the independent effect of excess adiposity on peak luteinizing hormone(LH) level of stimulation test in ICPP girls and the role of other related factors. A retrospective cross-sectional study was performed on 618 girls diagnosed as having ICPP, including 355 cases of normal weight, 99 cases of overweight and 164 cases of obese. The results showed that obese group had more progressed Tanner stage and no significant difference(P=0.28) in LH peak was found as basal LH value was used as a covariate. The obese group had higher total testosterone(TT), adrenocorticotrophic hormone(ACTH), 17-α hydroxyprogesterone(17-αOHP) and androstendione(AN), with significantly increased fasting insulin(FIN) and homeostasis model of assessment for insulin resistance index(HOMA-IR). Stratified analysis showed inconsistency of the relationship between BMI-standard deviation score(BMI-SDS) and LH peak in different Tanner stages(P for interaction=0.017). Further smoothing plot showed linear and non-linear relationship between BMI-SDS and LH peak in three Tanner stages. Then linear regression model was used to analyze the relationship between BMI-SDS and LH peak in different Tanner stages, with and without different confounding factors being adjusted. In B2 stage, BMI-SDS was negatively associated with LH peak. In B3 stage, when BMI-SDS 〈1.5, as BMI-SDS increased, the level of LH peak decreased(model Ⅰ: β=–1.8, 95% CI=–4.7 to 1.1, P=0.214). When BMI-SDS ≥1.5, BMI-SDS was significantly positively associated with LH peak(model Ⅰ: β=4.5, 95% CI=1.7 to 7.4, P=0.002). In B4 stage, when BMI-SDS 〈1.5, BMI-SDS was negatively associated with LH peak(model Ⅰ: β=–11.6, 95% CI=–22.7 to –0.5, P=0.049). When BMI-SDS ≥1.5, BMI-SDS was positively associated with LH peak(model Ⅰ: β=–4.2, 95% CI=–3.3 to 11.7, P=0.28). It is concluded that there is an independent correlation between BMI-SDS and LH peak of stimulation test in ICPP girls, their relationships are different in different Tanner stages, and the effect of BMI-SDS can be affected by adrenal androgens, estradiol and glucose metabolism parameters. 展开更多
关键词 obesity luteinizing hormone body mass index-standard deviation score idiopathic central precocious puberty
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中亚地区2001-2020年250 m及2020年30 m分辨率植被生长季NDVI数据集
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作者 高超 任小丽 +4 位作者 曾纳 刘畅 张心昱 张黎 何洪林 《中国科学数据(中英文网络版)》 CSCD 2024年第3期1-11,共11页
中亚地区是北半球最大的干旱和半干旱区,其生态环境十分脆弱,对全球气候变化的响应较为敏感。由于该区域的特殊地理位置,维护该区域生态系统的稳定对全球经济社会发展至关重要。植被具有重要的生态环境指示作用,其时空分布格局和变化趋... 中亚地区是北半球最大的干旱和半干旱区,其生态环境十分脆弱,对全球气候变化的响应较为敏感。由于该区域的特殊地理位置,维护该区域生态系统的稳定对全球经济社会发展至关重要。植被具有重要的生态环境指示作用,其时空分布格局和变化趋势是评估区域生态状况的重要指标。归一化植被指数(Normalized Difference Vegetation Index,NDVI)作为研究植被最常用的遥感指数之一,能够表征植被的时空变化特征。本数据集利用MODIS13Q1产品生成了中亚地区2001–2020年长时间序列空间分辨率为250 m的生长季均值NDVI数据,并使用基于规则的分段回归Cubist算法,结合Landsat数据,融合得到了能够更好表征地物细节的30 m空间分辨率的2020年生长季均值NDVI数据。同时,本数据集从数据源的质控,模型训练优化,以及模型独立验证三个方面对数据产品进行质量控制,以确保数据的精度和可靠性。本数据集的生成为中亚地区植被动态变化和空间格局的分析提供了有力的数据支持。 展开更多
关键词 归一化植被指数 中亚 多源遥感数据融合 遥感产品
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基于DEA-Malmquist指数的我国中部地区物流效率分析
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作者 陈祥兵 程龙 《物流科技》 2024年第19期17-20,共4页
以2012—2021年我国中部地区(山西、河南、安徽、湖北、江西、湖南)六省的物流行业相关面板数据为对象构建评价指标体系,运用DEA-Malmquist指数模型,分别对其进行静态分析以及动态分析,进而得出相关结论,并由此给出提高物流效率的可行... 以2012—2021年我国中部地区(山西、河南、安徽、湖北、江西、湖南)六省的物流行业相关面板数据为对象构建评价指标体系,运用DEA-Malmquist指数模型,分别对其进行静态分析以及动态分析,进而得出相关结论,并由此给出提高物流效率的可行性建议。结果表明:2012—2021年间中部地区的物流效率一直未达到有效,且技术是中部各省物流效率的主要问题,同时生产率也略微退步,针对这些问题,中部地区需要加强区域协同作用以及推动物流技术的进步,也需要探索创新人才培养制度,吸引高技术人才。 展开更多
关键词 DEA模型 MALMQUIST指数 中部地区 物流效率
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基于德尔菲法构建集采中选药品管理敏感指标
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作者 孙忠华 高平 +3 位作者 李娜 徐驰 李相成 贾秀玲 《中国药事》 CAS 2024年第6期627-633,共7页
目的:构建集采中选药品管理敏感指标。方法:通过循证初步建立集采中选药品管理敏感指标,再通过德尔菲专家函询法对30名药学人员进行2轮函询,并统计整理函询结果。结果:构建的集采中选药品管理敏感指标包括一级指标3项,二级指标11项和三... 目的:构建集采中选药品管理敏感指标。方法:通过循证初步建立集采中选药品管理敏感指标,再通过德尔菲专家函询法对30名药学人员进行2轮函询,并统计整理函询结果。结果:构建的集采中选药品管理敏感指标包括一级指标3项,二级指标11项和三级指标22项。两轮专家函询有效回收率分别为91%和100%。第二轮权威系数为0.82,总体协调系数0.434,检验具有统计学意义(P<0.01)。结论:本研究构建的集采中选药品管理敏感指标满足专家积极程度、权威程度和一致性标准等各项标准。 展开更多
关键词 药品集中带量采购 敏感指标 德尔菲专家函询法 药品管理 药事管理
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Correlation between obstructive sleep apnea and central retinal vein occlusion 被引量:1
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作者 Yan-Hui Wang Peng Zhang +4 位作者 Lian Chen Zhao Jiang Lu-Xi Li Ke He Xiao-Qing Li 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第10期1634-1636,共3页
To investigate the possible correlation between obstructive sleep apnea(OSA) and central retinal vein occlusion(CRVO). Thirty consecutive patients with a recent(<3 mo)CRVO and an age-and sex-matched group of 30 con... To investigate the possible correlation between obstructive sleep apnea(OSA) and central retinal vein occlusion(CRVO). Thirty consecutive patients with a recent(<3 mo)CRVO and an age-and sex-matched group of 30 control subjects were recruited. All subjects underwent full-night polysomnography to measure apnea-hypopnea index(AHI)and oxygen desaturation index(ODI). The average AHI and ODI were significantly higher in CRVO patients(AHI:13.86±8.63, ODI: 9.21±4.47) than in control subjects(AHI:8.51±6.36, ODI: 5.87±3.18;P=0.008 and 0.001 respectively).Additionally, the AHI was positively correlated with body mass index(BMI;r=0.476, P=0.017) and ODI(r=0.921,P<0.01) in both CRVO and control subjects. According to AHI scores, twenty-two(73.33%) CRVO patients had OSA and 12(40.00%) control subjects had OSA, a difference that was statistically significant(P=0.019). OSA may be a risk factor for or a trigger of CRVO development. 展开更多
关键词 central retinal VEIN occlusion OBSTRUCTIVE sleep APNEA POLYSOMNOGRAPHY apnea-hypopnea index oxygen desaturation index
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Assessment of Drought Vulnerability and Occurrence Zones in North Central Nigeria
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作者 Oye Ideki Vincent E. Weli 《Atmospheric and Climate Sciences》 2019年第3期298-309,共12页
Assessment of drought vulnerability and occurrence zones in North Central Nigeria was carried out in this study using standardized Precipitation Index (SPI). The Standardized Precipitation Index (SPI) 12 months’ time... Assessment of drought vulnerability and occurrence zones in North Central Nigeria was carried out in this study using standardized Precipitation Index (SPI). The Standardized Precipitation Index (SPI) 12 months’ time scale was computed from long-term rainfall data between 1960 and 2015 obtained from the Nigerian Meteorological Agency (NIMET) Abuja. The SPI results were further subjected to Mann-Kendal and Sen’s slope analysis for trend detection. To assess the vulnerability of drought and occurrence zones, the SPI and other geo-spatial techniques were employed to generate drought vulnerability maps for three epochs: 2000-2005, 2005-2010 and 2010-2015 respectively. The SPI values were interpolated using Inverse Weighted (IDW) techniques in ArcGIS10.5 to generate the vulnerability maps for the selected model years. The outcome of drought trend and vulnerability maps reveals increasing drought trend dominated by near normal and moderate conditions in Abuja, Ilorin and Lokoja while moderate and severe droughts were observed in Minna and Jos. The study therefore recommends holistic drought monitoring and management strategies in order to mitigate its adverse impact on water resources and rainfall-dependent agriculture. 展开更多
关键词 DROUGHT VULNERABILITY Rainfall Standardized Precipitation index (SPI) OCCURRENCE ZONES NORTH central NIGERIA
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细胞凋亡、坏死和焦亡信号网络关键节点的识别 被引量:2
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作者 祁宏 王洋 石艳香 《河南师范大学学报(自然科学版)》 CAS 北大核心 2024年第1期51-59,共9页
细胞死亡作为一项基本的生命过程,在生物体的发育、自稳态和病理方面有重要作用.寻找细胞死亡信号通路中的关键节点一直是领域的研究焦点,而信号网络的构建及分析可为其提供重要的理论参考.主要关注凋亡、坏死和焦亡这3种研究最多的细... 细胞死亡作为一项基本的生命过程,在生物体的发育、自稳态和病理方面有重要作用.寻找细胞死亡信号通路中的关键节点一直是领域的研究焦点,而信号网络的构建及分析可为其提供重要的理论参考.主要关注凋亡、坏死和焦亡这3种研究最多的细胞死亡方式.首先从已发表文献和生物信息数据库中获取初步数据,对数据进行文本处理,利用处理后的数据构建凋亡、坏死和焦亡的信号网络.然后分别计算各网络的度中心性、介数中心性、接近中心性和特征向量中心性指标,并利用k-壳分解和社团发现方法对节点进行不同的划分.最终综合上述方法所得结果,鉴定出各网络中的关键节点. 展开更多
关键词 细胞死亡 信号网络 中心性指标 k-壳分解 社团发现
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基于智能索引算法的集控设备事故辅助预警方法研究
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作者 李鹏 林显 曾旭川 《电子设计工程》 2024年第5期131-135,共5页
为了保障电力集控中心设备正常运转,针对信息检索效率较差、电压偏差控制效果较差的问题,研究基于智能索引算法的集控设备事故辅助预警方法。利用R-树索引算法检索集控设备运行数据集内设备事故数据;计算集控设备事故数据状态向量间的... 为了保障电力集控中心设备正常运转,针对信息检索效率较差、电压偏差控制效果较差的问题,研究基于智能索引算法的集控设备事故辅助预警方法。利用R-树索引算法检索集控设备运行数据集内设备事故数据;计算集控设备事故数据状态向量间的相似度,将该相似度组成相似度向量后,利用滑动窗口算法计算集控设备事故辅助预警阈值,当集控设备事故数据状态向量相似度低于该阈值时,则向用户发出设备事故辅助报警。实验结果表明,该方法采集集控设备电压偏差仅为0.05 V左右,可有效采集集控设备运行数据;检索设备事故信息较为迅速和准确。 展开更多
关键词 智能索引算法 集控设备事故 辅助预警方法 关联规则
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不同蛋白质、能量水平饲粮对舍饲育肥牦牛生长性能、养分表观消化率及血清生化指标的影响 被引量:1
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作者 何振富 谢建鹏 +2 位作者 陈平 王斐 狄亚鹏 《动物营养学报》 CAS CSCD 北大核心 2024年第3期1698-1712,共15页
本试验旨在研究不同蛋白质、能量水平饲粮对舍饲育肥牦牛生长性能、养分表观消化率和血清生化指标的影响。选取年龄相近、体况良好、体重[(180.00±11.67)kg]相近的公牦牛90头,随机分为9组,每组10头。采用2因素3水平随机区组进行设... 本试验旨在研究不同蛋白质、能量水平饲粮对舍饲育肥牦牛生长性能、养分表观消化率和血清生化指标的影响。选取年龄相近、体况良好、体重[(180.00±11.67)kg]相近的公牦牛90头,随机分为9组,每组10头。采用2因素3水平随机区组进行设计,即低(12.5%)、中(15.5%)、高(18.5%)3个蛋白质水平和低(6.5 MJ/kg)、中(7.5 MJ/kg)、高(8.5 MJ/kg)3个综合净能水平,按3×3(蛋白质水平×综合净能水平)设计9种不同蛋白质和能量水平的全混合日粮(TMR),每个试验组饲喂1种,预试期20 d,正试期90 d。结果表明:1)饲粮蛋白质水平对所测各生长性能指标影响均不显著(P>0.05);饲粮综合净能水平对总增重(TWG)和平均日增重(ADG)影响显著(P<0.05),对料重比(F/G)影响极显著(P<0.01);饲粮蛋白质水平和综合净能水平两者交互对TWG、ADG和F/G影响极显著(P<0.01)。2)饲粮蛋白质水平对粗蛋白质(CP)和粗灰分(Ash)表观消化率影响极显著(P<0.01),对酸性洗涤纤维(ADF)、中性洗涤纤维(NDF)和粗纤维(CF)表观消化率影响显著(P<0.05);饲粮综合净能水平对Ash表观消化率影响显著(P<0.05);饲粮蛋白质水平和综合净能水平两者交互对干物质(DM)和Ash表观消化率影响显著(P<0.05)。3)饲粮蛋白质水平对血清尿素氮(UN)含量影响极显著(P<0.01),对磷(P)含量影响显著(P<0.05);饲粮综合净能水平对血清总蛋白(TP)、白蛋白(ALB)、UN、甘油三酯(TG)和总胆固醇(TC)含量影响极显著(P<0.01),对总胆汁酸(TBA)含量影响显著(P<0.05);饲粮蛋白质水平和综合净能水平两者交互对血清碱性磷酸酶(ALP)活性和UN含量影响极显著(P<0.01),对肌酐(CRE)和P含量影响显著(P<0.05)。由此得出,在本试验条件下,饲粮综合净能水平对牦牛生长性能的影响大于蛋白质水平的影响;饲粮蛋白质水平对牦牛养分表观消化率的影响大于综合净能水平对其的影响;饲粮中综合净能水平为8.5 MJ/kg、蛋白质水平为15.5%时,舍饲育肥牦牛生长性能最佳。 展开更多
关键词 牦牛 舍饲 集中育肥 生长性能 养分表观消化率 血清生化指标
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基于长时间序列的中东大西洋渔获物平均营养级及资源状况变化分析
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作者 张忠 韩冠荣 +2 位作者 李楠 方舟 陈新军 《海洋渔业》 CSCD 北大核心 2024年第2期151-165,共15页
为了解中东大西洋渔业产区渔获物的资源状况,根据世界粮农组织(FAO)提供的该海域1950—2019年的渔获量数据,结合渔获种类的平均营养级(mean trophic level,MTL)信息,运用统计学方法分析70年间渔获物平均营养级和营养级平衡指数(fishing ... 为了解中东大西洋渔业产区渔获物的资源状况,根据世界粮农组织(FAO)提供的该海域1950—2019年的渔获量数据,结合渔获种类的平均营养级(mean trophic level,MTL)信息,运用统计学方法分析70年间渔获物平均营养级和营养级平衡指数(fishing in balance,FiB)的变动规律,以掌握该海域渔业资源的可持续利用情况。结果显示,MTL大致可分为4个阶段,1950—1956年,MTL指数在3.20左右,无明显变化;1957—1963年,MTL指数迅速上升至3.44;1964—1996年,MTL在波动中趋于下降,历史最高值(3.54)出现在1985年;1997—2019年,MTL稳定在较高水平,其中2018年为该阶段最低点3.35。FiB指数整体呈上升趋势,1950—1956年,FiB指数呈小幅波动增加;1957—1974年,FiB指数显著上升;1975—1996年,FiB指数呈平稳波动状态;1997—2019年,FiB指数整体呈小幅增长趋势。结果表明,中东大西洋海洋生态系统相对稳定,但潜在的渔业资源量越来越少,开发潜力有限。 展开更多
关键词 中东大西洋 渔业资源 平均营养级 FiB指数
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连铸机末端重压下对高建Z向钢铸坯质量的影响
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作者 栾文林 刘志远 +4 位作者 贾永杏 王重君 么敬文 郭文斌 宋月星 《河北冶金》 2024年第7期66-71,共6页
针对铸坯内部中心偏析、板材探伤合格率(80%以下)低的问题,河钢集团唐山中厚板材有限公司在280 mm×1800 mm断面板坯连铸机10#、11#扇形段位置实施了重压下技术,总压下量达到24 mm,在生产高建Z向钢时,铸坯致密度提高,中心偏析明显改... 针对铸坯内部中心偏析、板材探伤合格率(80%以下)低的问题,河钢集团唐山中厚板材有限公司在280 mm×1800 mm断面板坯连铸机10#、11#扇形段位置实施了重压下技术,总压下量达到24 mm,在生产高建Z向钢时,铸坯致密度提高,中心偏析明显改善,铸坯晶粒尺寸随着压下量的提高显著细化。利用低倍、金相组织分析,以及铸坯碳偏析指数、致密度和真密度等实验,分析了重压下对连铸坯内部质量的影响。结果表明:随着压下量的增加,铸坯中心偏析与疏松逐步改善,低倍C级品率由原来的85%提高至98%;连铸坯断面组织也发生晶粒的细化,有明显的细化晶粒效果;当铸坯中心偏析为C级1.0时,中心碳偏析指数均可有效控制在1.10以内;铸坯的真密度整体提升,重压下工艺下铸坯中心位置真密度提升0.17%;C级≤0.5级比例≥98%;铸坯中心偏析C级率(≤0.5级比例)综合比例达92.9%。重压下技术应用后,高建Z向钢铸坯晶粒尺寸随着压下量的提高显著细化,中心偏析得到明显改善。 展开更多
关键词 板坯连铸机 重压下工艺 低倍照片 金相组织 碳偏析指数 致密度 真密度
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