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Seasonal variations of adsorption/desorption equilibrium concentrations of P at water-sediment interface in different trophic states of Taihu Lake, China
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作者 Xiangcan JIN Xia JIANG Dongmei LIU 《Chinese Journal Of Geochemistry》 EI CAS 2006年第B08期164-164,共1页
关键词 太湖 季节变化 吸附作用 水文化学 交互作用
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Concentration difference of auxin involved in stem development in soybean 被引量:4
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作者 JIANG Zhen-feng LIU Dan-dan +4 位作者 WANG Tian-qiong LIANG Xi-long CUI Yu-hai LIU Zhi-hua LI Wen-bin 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2020年第4期953-964,共12页
Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different... Auxin regulates cell division and elongation of the primordial cells through its concentration and then shaped the plant architecture. Cell division and elongation form the internode of soybean and result in different plant heights and lodging resistance. Yet the mechanisms behind are unclear in soybean. To elucidate the mechanism of the concentration difference of auxin related to stem development in soybean, samples of apical shoot, elongation zone, and mature zone from the developing stems of soybean seedlings, Charleston, were harvested and measured for auxin concentration distributions and metabolites to identify the common underlying mechanisms responsible for concentration difference of auxin. Distribution of indole-3-acetic acid(IAA), indole-3-butyric acid(IBA), and methylindole-3-acetic acid(Me-IAA) were determined and auxin concentration distributions were found to have a complex regulation mechanism. The concentrations of IAA and Me-IAA in apical shoot were significantly different between elongation zone and mature zone resulting in an IAA gradient. Tryptophan dependent pathway from tryptamine directly to IAA or through indole-3-acetonitrile to IAA and from indole-3-propionic acid(IPA) to IAA were three primary IAA synthesis pathways. Moreover, some plant metabolites from flavonoid and phenylpropanoid synthesis pathways showed similar or reverse gradient and should involve in auxin homeostasis and concentration difference. All the data give the first insight in the concentration difference and homeostasis of auxin in soybean seedlings and facilitate a deeper understanding of the molecular mechanism of stem development and growth. The gathered information also helps to elucidate how plant height is formed in soybean and what strategy should be adopted to regulate the lodging resistance in soybean. 展开更多
关键词 SOYBEAN concentration differENCE of AUXIN STEM DEVELOPMENT metabolites
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Individual Differences in Blood Alcohol Concentrations after Moderate Drinking Are Mainly Regulated by Gastric Emptying Rate Together with Ethanol Distribution Volume 被引量:1
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作者 Shunji Oshima Takeshi Haseba +4 位作者 Chiaki Masuda Ema Kakimi Manabu Sami Tomomasa Kanda Youkichi Ohno 《Food and Nutrition Sciences》 2012年第6期732-737,共6页
Blood alcohol concentration (BAC) differs greatly among individuals, even when people of the same sex and age drink alcohol under the same drinking conditions. In this study, we investigated the main factors involved ... Blood alcohol concentration (BAC) differs greatly among individuals, even when people of the same sex and age drink alcohol under the same drinking conditions. In this study, we investigated the main factors involved in the internal reg-ulation of individual differences in BAC, focusing on the alcohol dehydrogenase 1B (ADH1B) genotype, blood acetal-dehyde concentration (BAcH), amount of habitual alcohol consumption, pharmacokinetic parameters of BAC, distribution volume of ethanol (Vd), and gastric emptying rate (GER) under the same drinking conditions. Twenty healthy Japanese males aged between 40 and 59 years old and having the aldehyde dehydrogenase 2 (ALDH2) genotype of ALDH 2*1/*2 were recruited for this study. The subjects were given 0.32 g ethanol/kg body weight in the form of commercially available beer (5%, v/v). The results showed that BAC-max differed greatly among individuals with a more than two-fold variation. When the BAC-time curve was compared among ADH1B genotypes (ADH1B*1/*1, *1/*2, and *2/*2), there were no differences in BAC among the genotypes. Although BAcH, monthly alcohol consumption, elimination rate of blood ethanol (β value) and ethanol disappearance rate from the body (EDR) can affect BAC, all of them had no correlations with BAC-max. However, Vd (liter/kg), ΔPlasma glucose concentration (ΔPGC = PGC30 min ? PGC0 min) and the serum concentration of gastric inhibitory polypeptide (GIP) did correlate with BAC-max. Model 2 in multiple linear regression analysis showed the optimal model for Vd and GIP with positive correlations with BAC-max. As GIP and ΔPGC are both reflected by gastric emptying rate (GER), we concluded that the individual differences in BAC after moderate drinking are mainly regulated by GER together with Vd. These findings demonstrate that together with body water content, the gastrointestinal tract plays an important role in the regulation of individual differences in BAC, involving first pass metabolism of ethanol. 展开更多
关键词 Individual differences Blood ETHANOL concentration MODERATE DRINKING GASTRIC EMPTYING Rate Distribution Volume
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Exact Distribution of Difference of Two Sample Proportions and Its Inferences 被引量:1
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作者 Keshab R. Dahal Mohamed Amezziane 《Open Journal of Statistics》 2020年第3期363-374,共12页
Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Ve... Comparing two population proportions using confidence interval could be misleading in many cases, such </span><span style="font-family:Verdana;">as</span><span style="font-family:Verdana;"> the sample size </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> small and the test </span><span style="font-family:Verdana;">being</span><span style="font-family:Verdana;"> based on normal approximation. In this case, the only </span><span style="font-family:Verdana;">one</span><span style="font-family:Verdana;"> option that we have is to collect a large sample. Unfortunately, the large sample might not be possible. One example is a person suffering from a rare disease. The main purpose of this journal is to derive a closed formula for the exact distribution of the difference between two independent sample proportions, and use it to perform related inferences such as a confidence interval, regardless of the sample sizes and compare with the existing Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score. In this journal, we have derived a closed formula for the exact distribution of the difference between two independent sample proportions. This distribution doesn’t need any </span><span style="font-family:Verdana;">requirements,</span><span style="font-family:Verdana;"> and can be used to perform inferences such </span><span style="font-family:Verdana;">as:</span><span style="font-family:Verdana;"> a hypothesis test for two population proportions, regardless of the nature of the distribution and the sample sizes. We claim </span><span style="font-family:Verdana;">that</span><span style="font-family:Verdana;"> exact distribution has the </span><span style="font-family:Verdana;">least</span><span style="font-family:Verdana;"> confidence width among Wald, Agresti-Caffo </span><span style="font-family:Verdana;">and</span><span style="font-family:Verdana;"> Score, so it is suitable for inferences of the difference between the population proportion regardless of sample size. 展开更多
关键词 Statistical Inferences Exact Distribution difference of Sample proportions
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Determination of Threshold Voltage and Mobility ofMOSFET by Proportional Difference Operator
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作者 王金延 许铭真 谭长华 《Journal of Semiconductors》 CSCD 北大核心 2000年第12期1198-1202,共5页
Proportional Difference Operator (PDO) method is proposed for the first time to determine the key parameters of a MOSFET, including the threshold voltage and ca rrier mobility.This method is applied to the transfer ch... Proportional Difference Operator (PDO) method is proposed for the first time to determine the key parameters of a MOSFET, including the threshold voltage and ca rrier mobility.This method is applied to the transfer characteristic of a MOSFET first, and then the effect of gate voltage on carrier mobility is considered. The dependence of carrier mobility on the gate voltage is obtained. 展开更多
关键词 proportional difference operator transfer char acteristic MOSFET
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Concentration of Bio-Ethanol through Cellulose Ester Membranes during Temperature-Difference Controlled Evapomeation 被引量:1
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作者 Tadashi Uragami 《Materials Sciences and Applications》 2011年第10期1499-1506,共8页
To evaluate the high-performance of membrane materials in the concentration of an aqueous solution of dilute bioethanol under temperature-difference controlled evapomeation (TDEV), asymmetric porous cellulose nitrate ... To evaluate the high-performance of membrane materials in the concentration of an aqueous solution of dilute bioethanol under temperature-difference controlled evapomeation (TDEV), asymmetric porous cellulose nitrate (CN) and cellulose acetate (CA) membranes were prepared by a phase inversion method. In the concentration of dilute ethanol under TDEV, these membranes showed a high permeation rate and high ethanol/water selectivity. In membranes with almost the similar pore size, the ethanol/water selectivity was considerably higher for the CN membrane than the corresponding CA membrane. This result suggested that the affinity between the membrane material and the permeant is an important factor in the separation selectivity. 展开更多
关键词 BIO-ETHANOL concentration Membrane Cellulose ESTER Temperature-difference CONTROLLED Evapomeation
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The application of a proportional difference type iterative learning control in active vibration control
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作者 HAO Xiao-hong ZHANG Lei LI Heng-jie 《通讯和计算机(中英文版)》 2008年第2期37-41,共5页
关键词 振动控制系统 频率 工程学 性能
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Safety Evaluation of Vegetables Growing in Soils Contaminated by Different Levels of Cadmium(Cd) 被引量:2
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作者 MI Bao-bin WANG Duan-hua +5 位作者 ZHANG Zhu-qing DAI Xiong-ze LIU Feng LIANG Cheng-liang XIE Ling-ling ZHOU Huo-qiang 《Agricultural Science & Technology》 CAS 2019年第1期15-21,共7页
The tested soils containing different Cd levels were obtained by mixing the normal cultivated soils with the Cd-contaminated soils taken from the paddies near a mine. Five major categories of vegetables, i.e. cucumber... The tested soils containing different Cd levels were obtained by mixing the normal cultivated soils with the Cd-contaminated soils taken from the paddies near a mine. Five major categories of vegetables, i.e. cucumber, cowpea, Bok choy, radish and lettuce, widely planted in the spring and autumn in Hunan Province, were selected for pool-culture experiments. Results showed that the Cd accumulations varied greatly according to the category of vegetables. The Cd accumulations in cucumber and cowpea growing in soils with high Cd levels (1.5 mg/kg) were within the threshold limits of the national standards, meaning that these two categories are safe to grow in Cd-contaminated soils. For either the cucumber or the cowpea category, there were no significant differences in the Cd accumulations of different genotypes. Most of the tested Bok choy and radish cultivars could grow safely in soils whose Cd levels were below 1.0 mg/kg. In comparison, the Cd accumulations in some cultivars tended to increase sharply as the Cd level in the soil went beyond 1.0 mg/kg. Significant variations were also observed in the Cd accumulations of different genotypes with mounting Cd levels in the soil. Besides, there were no positive correlations between Cd accumulations in plants and Cd levels in soils, indicating large fluctuations and poor ecological stability of Bok choy and radish. Therefore, the planting of Bok choy and radish should be strictly evaluated and controlled in Cdcontaminated regions. The Cd contents of most celtuce cultivars growing in mildlycontaminated soils had already exceeded the threshold limit. Therefore, it is not safe for celtuce to grow in Cd-contaminated environments. 展开更多
关键词 CD VEGETABLE difference in Cd accumulation concentration threshold
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Modeling Tracer Flow Characteristics in Different Types of Pores: Visualization and Mathematical Modeling 被引量:1
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作者 Tongjing Liu Weixia Liu +6 位作者 Pengxiang Diwu Gaixing Hu TingXu Yuqi Li Zhenjiang You Runwei Qiao Jia Wang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2020年第6期1205-1222,共18页
Structure of porous media and fluid distribution in rocks can significantly affect the transport characteristics during the process of microscale tracer flow.To clarify the effect of micro heterogeneity on aqueous tra... Structure of porous media and fluid distribution in rocks can significantly affect the transport characteristics during the process of microscale tracer flow.To clarify the effect of micro heterogeneity on aqueous tracer transport,this paper demonstrates microscopic experiments at pore level and proposes an improved mathematical model for tracer transport.The visualization results show a faster tracer movement into movable water than it into bound water,and quicker occupancy in flowing pores than in storage pores caused by the difference of tracer velocity.Moreover,the proposed mathematical model includes the effects of bound water and flowing porosity by applying interstitial flow velocity expression.The new model also distinguishes flowing and storage pores,accounting for different tracer transport mechanisms(dispersion,diffusion and adsorption)in different types of pores.The resulting analytical solution better matches with tracer production data than the standard model.The residual sum of squares(RSS)from the new model is 0.0005,which is 100 times smaller than the RSS from the standard model.The sensitivity analysis indicates that the dispersion coefficient and flowing porosity shows a negative correlation with the tracer breakthrough time and the increasing slope,whereas the superficial velocity and bound water saturation show a positive correlation. 展开更多
关键词 Tracer flow characteristics different types of pores interstitial flow velocity visualization and mathematical modeling tracer concentration prediction model
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Temporal Sequence of Sweetness Perception in Fruit-Flavored Tea: A Descriptive Report on the Influence of Sucrose Concentrations on the Sensation
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作者 Suzuka Akemura Nomo Hasebe +3 位作者 Madoka Kasahara Honami Sakai Eri Sanada Yozo Miyaoka 《Food and Nutrition Sciences》 2019年第1期110-117,共8页
The goals of this study were to examine, using the temporal dominance of sensations (TDS) method, the effects of 1) the sucrose concentration on the temporal sequence of sweetness perception in four fruit-flavored (le... The goals of this study were to examine, using the temporal dominance of sensations (TDS) method, the effects of 1) the sucrose concentration on the temporal sequence of sweetness perception in four fruit-flavored (lemon, peach, strawberry, and vanilla) teas with 0.05, 0.15, and 0.25 M sucrose;and 2) participants’ sex on this temporal sequence. Twenty-four healthy young adults were assigned to female (n = 12) and male (n = 12) groups. Both groups evaluated five sensory attributes in 12 samples (four fruit-flavored teas, each with three sucrose concentrations). As in our preceding study [1], two sensations, sweetness and fruitiness, were dominant after ingesting the 12 teas in both groups, but the temporal sequence of sweetness perception differed between the two groups. On average, the male group reported the first appearance of sweetness earlier in the samples with 0.05 M sucrose compared with the female group, with the samples containing 0.15 and 0.25 M sucrose. The average durations of the sweetness sensation were different between the male and female groups as well as among the sucrose concentrations and the four flavors tested. 展开更多
关键词 TEA SWEETNESS Flavor SUCROSE concentration TEMPORAL Dominance of SENSATIONS Sex differences
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The Combined Impact of Magnetic Field and Chloride Ion Concentration on Corrosion Behavior of Al-Mg Alloys
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作者 ZHANG Xin HUANG Lianpeng +4 位作者 TAO Jiahao WANG Zehua ZHOU Zehua CAI Xin WEN Tao 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2022年第6期1192-1203,共12页
The impact of magnetic field on the corrosion behavior of Al-Mg-xR_(E)/Fe alloys in NaCl solutions with concentrations of 1.5wt%,3.5wt%,and 5.5wt%were studied by microstructure observation,immersion test,and electroch... The impact of magnetic field on the corrosion behavior of Al-Mg-xR_(E)/Fe alloys in NaCl solutions with concentrations of 1.5wt%,3.5wt%,and 5.5wt%were studied by microstructure observation,immersion test,and electrochemical test.The combined impacts of magnetic field and chloride ion concentration on the corrosion behavior of Al-Mg alloys with various electrode potential phases were discussed.The results indicate that Al-3.0Mg-xR_(E)/Fe alloys corrode faster and have a higher pitting corrosion potential in the NaCl solution with a higher concentration.In addition,a magnetic field can lower the pitting sensitivity and corrosion rate of Al-3.0Mg and Al-3.0Mg-0.2R_(E)/Fe alloys in NaCl solution with different concentrations.However,at a higher concentration of NaCl solution,the magnetic field has a weaker inhibiting effect on corrosion rate and pitting sensitivity.In NaCl solutions with concentrations of 1.5wt%and 3.5wt%,the corrosion rate and pitting sensitivity of Al-3.0Mg-1.0R_(E)/Fe alloys can be reduced by a magnetic field.However,in NaCl solution with the concentration of 5.5wt%,the corrosion rate of the alloys is increased by a magnetic field. 展开更多
关键词 magnetic field corrosion behavior chloride ion concentration different electrode potential phases
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SENSITIVITY OF THE CONCENTRATION CHANGE OF DYE DISPENSING USING COMPUTER SYSTEMS
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作者 D.P.Oulton 陈平彪 《Journal of China Textile University(English Edition)》 EI CAS 1993年第4期81-88,共8页
This paper employs computer colour generation,and match prediction systems and aims tofind the most critical change of dye concentration corresponding to changes of Hue,or Chroma,orLightness of 1 unit just visible col... This paper employs computer colour generation,and match prediction systems and aims tofind the most critical change of dye concentration corresponding to changes of Hue,or Chroma,orLightness of 1 unit just visible colour difference,thus investigating the required accuracy level fordyeing dispensing.This leads to the selection of one critical colour-difference dimension of threefrom CMC (1:c) measurement.The results reveal that the concentration change in dye dispensing ismost critical for change of Hue in a computer controlled system.The formula describing the rela-tionship Of △E and △H in CMC (2:1) measurement is selected for further investigation. 展开更多
关键词 DYE concentration CHANGE DYE DISPENSING DYE formulation computer colourmatching colour-difference FORMULAE
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Decomposing scheelite and scheelite-wolframite mixed concentrate by caustic soda digestion
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作者 孙培梅 李洪桂 +4 位作者 李运姣 赵中伟 霍广生 孙召明 刘茂盛 《Journal of Central South University of Technology》 2003年第4期297-300,共4页
Scheelite and scheelite-wolframite mixed concentrates with different grades were decomposed by caustic soda digestion, and the effects of caustic soda(NaOH) dosage, the ratio of water to ore and the stirring rate on... Scheelite and scheelite-wolframite mixed concentrates with different grades were decomposed by caustic soda digestion, and the effects of caustic soda(NaOH) dosage, the ratio of water to ore and the stirring rate on tungsten recovery were studied. The results show that under the conditions that the ratio of water to ore is (0.8,) stirring rate is 500 r·min-1 and the heating time is 2.0 h at (160 ℃,) the recovery of tungsten reaches 98% for scheelite (w(WO3) is (65.04%)) and wolframite containing high proportion of calcium (w(WO3) is 65.58%, w(Ca) is (7.53%),) when caustic soda dosage is 2.2 and 2.0 times of theoretical value, respectively; the recovery of tungsten can be more than 98%,98% and 96% respectively for low-grade scheelite-wolframite mixed concentrate with (55.78%,) 45.32% and 25.21% WO3, when caustic soda dosage is 2.6,3.2 and 5.5 times of theoretical value, respectively. 展开更多
关键词 SCHEELITE concentrATE WOLFRAMITE with high proportion of calcium low-grade scheelite-wolframitemixed concentrATE CAUSTIC SODA DIGESTION
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Comparison of high-energy multi-pass Ti:sapphire amplifiers with a different Ti-dopant concentration
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作者 Zebiao Gan Xiaoyan Liang +4 位作者 Lianghong Yu Jiaqi Hong Ming Xu Ying Hang Ruxin Li 《Chinese Optics Letters》 SCIE EI CAS CSCD 2017年第9期66-70,共5页
We experimentally compare the output abilities of lightly and heavily doped Ti:Sapphire(Ti:S) amplifiers with diameters as large as 150 mm. Although a lightly doped Ti:S is more favorable to overcome parasitic la... We experimentally compare the output abilities of lightly and heavily doped Ti:Sapphire(Ti:S) amplifiers with diameters as large as 150 mm. Although a lightly doped Ti:S is more favorable to overcome parasitic lasing(PL)and transverse amplified spontaneous emission(TASE), the self-phase-modulation(SPM) effect becomes more pronounced when a longer crystal is used. Recompression of the amplified, stretched pulses can be seriously affected by the SPM effect. We then propose a temporal multi-pulse pump scheme to suppress PL and TASE in a thin, heavily doped Ti:S crystal. This novel temporal multi-pulse pump technique can find potential applications in 10 PW chirped-pulse amplification laser systems. 展开更多
关键词 TI Comparison of high-energy multi-pass Ti:sapphire amplifiers with a different Ti-dopant concentration SPM
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牛栏江—滇池补水工程水源区不同时间尺度径流变化特征 被引量:1
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作者 李宝芬 崔松云 +2 位作者 王东升 杨绍琼 卢书梅 《水电能源科学》 北大核心 2024年第1期5-9,共5页
为做好补水工程水资源调度、配置、流域水安全治理和区域防汛抗旱工作,充分发挥工程效益,基于牛栏江—滇池补水工程水源区代表站长系列水文资料,采用集中度、不均匀系数、Hurst系数、M-K趋势检验、滑动T检验等多种方法分析了牛栏江—滇... 为做好补水工程水资源调度、配置、流域水安全治理和区域防汛抗旱工作,充分发挥工程效益,基于牛栏江—滇池补水工程水源区代表站长系列水文资料,采用集中度、不均匀系数、Hurst系数、M-K趋势检验、滑动T检验等多种方法分析了牛栏江—滇池补水工程水源区不同时间尺度径流变化特征。结果表明,水源区不同时间尺度径流年际变化大、丰-平-枯周期明显;年内分配向均匀性和坦化趋势演变;最小1、7 d径流显著上升,其他7个径流趋势变化不显著,均发生突变;年、丰水期、极端最大等5个径流指标突变后径流量减少明显,枯水期和极端最小等4个径流指标突变后为增长趋势;年径流突变后8~10月来水量减少明显;预计补水工程水源区未来一段时间不易发生极端枯水事件,但总来水量可能会进一步衰减。 展开更多
关键词 径流变化 不均匀系数 集中度 Hurst系数 突变分析 不同时间尺度
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Finite Difference Method for Solving Material Balance Equation in Lithium-Ion Cell
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作者 Yusof Norzihani Hashim Ali Siti Aishah Arof Abdul Kariem 《材料科学与工程(中英文版)》 2010年第11期94-99,共6页
关键词 平衡方程 锂离子 差分方法 电池材料 有限元 求解 相分离器 电池放电
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利用数字化仪实现放射性气体^(85)Kr核素活度浓度的绝对测量
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作者 拓飞 路天翔 +3 位作者 张明 周倩倩 郭贵银 王硕 《计量学报》 CSCD 北大核心 2024年第10期1570-1575,共6页
基于中国计量科学研究院建立的长度补偿法充气正比计数器绝对测量系统,利用CAEN公司开发的DT5730型数字化仪替代多套传统模拟电子学插件,并通过数字化仪对β信号进行采集、重建和数据离线分析,开展^(85)Kr放射性惰性气体活度浓度的绝对... 基于中国计量科学研究院建立的长度补偿法充气正比计数器绝对测量系统,利用CAEN公司开发的DT5730型数字化仪替代多套传统模拟电子学插件,并通过数字化仪对β信号进行采集、重建和数据离线分析,开展^(85)Kr放射性惰性气体活度浓度的绝对测量。实验研究了各种条件的影响,通过对正比计数器端效应、正比计数器壁效应、本底、噪声、死时间漏计数和阈值以下计数进行修正,最终得到^(85)Kr活度浓度绝对测量结果。在相同阈值、主放大倍数100倍、气压50.5 kPa,工作电压1675 V和1700 V的条件下,数字化仪测量和电子学插件测量^(85)Kr放射性活度浓度的相对偏差分别为0.83%和0.74%。测量结果在不确定度范围内一致,证明数字化仪可有效替代传统电子学插件实现放射性惰性气体^(85)Kr活度浓度的绝对测量。 展开更多
关键词 电离辐射计量 数字化仪 ^(85)Kr 正比计数器 放射性活度浓度 绝对测量
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甘肃产不同品种松针的抗氧化活性研究
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作者 刘东彦 石晓峰 +2 位作者 王信 马趣环 沈薇 《林产工业》 北大核心 2024年第1期39-44,共6页
以甘肃产白皮松、雪松、油松、落叶松、樟子松和华山松6个树种的松针为研究对象,采用DPPH法、ABTS法和铜离子还原能力测定其不同浓度乙醇提取物的体外抗氧化活性,并采用熵值法综合评价遴选出抗氧化活性强的松针资源,为松针的进一步开发... 以甘肃产白皮松、雪松、油松、落叶松、樟子松和华山松6个树种的松针为研究对象,采用DPPH法、ABTS法和铜离子还原能力测定其不同浓度乙醇提取物的体外抗氧化活性,并采用熵值法综合评价遴选出抗氧化活性强的松针资源,为松针的进一步开发利用提供参考。研究表明:采用不同浓度乙醇提取时,40%乙醇提取物的抗氧化活性最好;不同品种松针中,雪松松针的抗氧化活性最好,其中天水产雪松松针40%乙醇提取物的评分最高达99.52%,表明其可以作为进一步研究松针抗衰老研究的资源。 展开更多
关键词 松针 不同浓度乙醇提取物 抗氧化活性 熵值法 综合评价
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不同浓度罗哌卡因用于超声引导下TAP阻滞在妇科手术中的镇痛效果及安全性
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作者 邹蓉 杨程 +1 位作者 朱娟 张杰 《中国计划生育学杂志》 2024年第3期548-552,共5页
目的:探讨不同浓度罗哌卡因用于超声引导下腹横肌平面(TAP)阻滞在妇科手术中的临床效果。方法:将2021年4月-2023年4月于本院行全身麻醉下腹腔镜子宫全切术患者105例,依据双盲法分为3组,分别给予0.25%、0.30%、0.375%罗哌卡因。对比各组... 目的:探讨不同浓度罗哌卡因用于超声引导下腹横肌平面(TAP)阻滞在妇科手术中的临床效果。方法:将2021年4月-2023年4月于本院行全身麻醉下腹腔镜子宫全切术患者105例,依据双盲法分为3组,分别给予0.25%、0.30%、0.375%罗哌卡因。对比各组手术相关指标,不同时间点患者疼痛和舒适度评分变化,麻醉前后患者炎症因子水平,术后24h不良反应。结果:3组麻醉时间、术中出血量、手术时间均无差异(P>0.05);与术后1h对比,术后24h各组视觉模拟评分(VAS)均下降,Bruggrmann舒适度评分(BCS)均提升,但0.375%组VAS评分(1.56±0.51分)低于0.25%组(2.69±1.02分)、0.30%组(2.35±0.68分),BCS评分(3.24±0.54分)高于0.25%组(2.23±0.39分)、0.30%组(2.59±0.41分)(P<0.05);麻醉后各组C反应蛋白(CRP)、肿瘤坏死因子α(TNF-α)水平均提升,但0.375%组CRP(21.36±4.26 mg/L)、TNF-α(70.13±7.16 pg/ml)水平低于0.25%组(28.98±5.62 mg/L、96.54±8.97 pg/ml)、0.30%组(24.69±4.87 mg/L、84.33±7.62 pg/ml),不良反应发生率0.375%组(8.6%)低于0.25%组(40.0%)、0.30%组(31.4%)(均P<0.05)。结论:0.375%浓度罗哌卡因在超声引导下妇科TAP阻滞术中应用,改善患者疼痛效果显著,提升患者术后舒适度,有助于降低术后不良反应发生风险,提高用药安全性。 展开更多
关键词 妇科手术 超声引导 腹横肌平面阻滞术 罗哌卡因 不同浓度 麻醉效果 镇痛
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科研人员职业生涯成长轨迹的性别差异研究——以图情档学科国家社科基金一般项目获批者为例
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作者 谭春辉 李明磊 +2 位作者 王仪雯 毕慧婷 王学东 《现代情报》 CSSCI 北大核心 2024年第7期125-134,共10页
[目的/意义]性别差异问题在科研人员队伍中普遍存在,对科研人员职业生涯成长轨迹中的性别差异进行研究对于制定人才培养和成长政策具有重要意义。[方法/过程]本研究以2018—2022年图书馆、情报与文献学学科国家社科基金一般项目的负责... [目的/意义]性别差异问题在科研人员队伍中普遍存在,对科研人员职业生涯成长轨迹中的性别差异进行研究对于制定人才培养和成长政策具有重要意义。[方法/过程]本研究以2018—2022年图书馆、情报与文献学学科国家社科基金一般项目的负责人为研究对象,对379名科研人员的履历信息进行编码处理,采用生存分析法研究了科研人员职业生涯成长轨迹中的性别差异及影响因素。[结果/结论]研究发现,图情档学科科研人员获得国家社科一般项目支持的群体中高级职称的占比男性较高于女性,其他无显著差异。Kaplan-Meier分析表明,科研人员职业生涯成长过程中存在着显著的性别差异,男性科研人员的成长速度在总体上要快于女性。Cox分析结果表明,年龄在各个阶段对男性和女性的生存风险均有降低作用,会延缓科研人员的成长;机构流动经历会增加男性科研人员在副高阶段的生存风险,会加快其职称晋升速度;国外留学访学经历会增加女性科研人员在正高阶段的生存风险从而加快在该阶段的成长。研究结果为改善科研人员的性别差异提供一定的启示。 展开更多
关键词 科研人员 成长轨迹 性别差异 履历分析 生存分析 Cox比例风险回归
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