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尺骨变异在健康人群中的分布 被引量:2
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作者 刘杰 刘名 +1 位作者 何磊 孙广超 《中国矫形外科杂志》 CAS CSCD 北大核心 2008年第21期1637-1640,共4页
[目的]探讨尺骨变异与性别和年龄之间的关系。[方法]随机选取健康志愿者200名,均为右利手。入选标准为既往无急、慢性腕关节疾病及腕部和前臂骨折病史。其中男117名,女83名;年龄18~84岁,平均41.7±16.4岁。对入选者拍摄标准... [目的]探讨尺骨变异与性别和年龄之间的关系。[方法]随机选取健康志愿者200名,均为右利手。入选标准为既往无急、慢性腕关节疾病及腕部和前臂骨折病史。其中男117名,女83名;年龄18~84岁,平均41.7±16.4岁。对入选者拍摄标准腕关节正位X线片,测量取得309个尺骨变异数值,按照性别、年龄、左右侧腕分组后分别进行统计学分析。[结果]在全体健康者中,尺骨变异发生率为:正向变异48.9%,中性变异39.8%,负向变异11.3%。在男性健康者中,三种尺骨变异的发生率为:正向变异50.0%,中性变异39.2%,负向变异10.8%;女性健康者中,三种尺骨变异的发生率为:正向变异47.4%,中性变异40.6%,负向变异12.0%。结果显示随着年龄的增长,尺骨变异出现正向和负向变异的比率增高,而中性尺骨变异的比率降低。这种变化规律在男女性别之间无明显差异。左腕尺骨变异发生率为:正向变异49.7%,中性变异39.3%,负向变异11.0%。右腕的正向变异为48.2%,中性变异为40.6%,负向变异为11.5%。两侧尺骨变异的分布无明显区别。[结论](1)在健康人群中,主要为正向和中性尺骨变异,负向尺骨变异较少。(2)随着年龄的增长,尺骨变异发生动态变化。(3)在健康的男女性人群中,尺骨变异性的分布无明显差异。(4)在健康人群中,腕部日常的活动对尺骨变异的分布和变化无影响。 展开更多
关键词 尺骨变异 正向变异 中性变异 负向变异
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不仅仅是遗传多样性:植物保护遗传学进展 被引量:11
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作者 王峥峰 葛学军 《生物多样性》 CAS CSCD 北大核心 2009年第4期330-339,共10页
保护遗传学研究的是影响物种灭绝的遗传因素以及濒危物种的遗传管理,以降低物种的灭绝风险。本文从遗传多样性本身及其对生态系统的影响两个方面介绍了植物保护遗传学的最新进展。根据遗传标记的功能,保护遗传学研究可分为选择中性遗传... 保护遗传学研究的是影响物种灭绝的遗传因素以及濒危物种的遗传管理,以降低物种的灭绝风险。本文从遗传多样性本身及其对生态系统的影响两个方面介绍了植物保护遗传学的最新进展。根据遗传标记的功能,保护遗传学研究可分为选择中性遗传变异研究和适应性遗传变异两个方面。对于目前主要采用的选择中性遗传标记研究,本文着重介绍了以下方面的最新进展:(1)利用遗传标记进行个体、物种或遗传单元的鉴定,从而有效地设计保护策略,避免在迁地保护中混淆物种,提高保护效率;(2)应重视由于物种自身生殖、扩散等原因造成的隐性瓶颈效应。由于选择中性遗传标记并不能准确反映物种的适应性遗传基础,从适应性遗传变异角度研究濒危物种的进化潜力已成为保护遗传学的研究前沿。大部分相关研究还集中在利用基因组扫描检测受选择的位点,而对功能基因的适应性研究还比较少。景观遗传学旨在解释景观和生境影响下的种群间基因流和遗传多样性格局,这方面研究将会促进我们更多了解种群基因流的地理限制因子和不同景观基质下的种群遗传差异。遗传多样性作为物种的一种属性亦可在一定程度上反馈,并影响生态系统。这提示我们不仅仅是濒危物种,常见物种的遗传多样性及其保护亦很重要。最后,我们从4个方面对保护遗传学研究进行了展望,包括应加强将生态系统各环节联系起来研究遗传多样性,在技术手段上利用多态性更丰富的分子标记,同时强调了对常见物种保护遗传学研究的重要性,并初步分析了我国保护遗传学研究与国际水平的差距,建议加强种群遗传学和进化生物学基础理论的学习。 展开更多
关键词 选择中性遗传变异 适应性遗传变异 景观遗传学 生态系统
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Genetic variability of CYP2B6 polymorphisms in four southern Chinese populations 被引量:6
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作者 Bing-Ying Xu Li-Ping Guo +7 位作者 Shui-Shan Lee Qing-Ming Dong Yi Tan Hong Yao Li-Hua Li Che-Kit Lin Hsiang-Fu Kung Ming-Liang He 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第14期2100-2103,共4页
AIM: To investigate the genotype and allelic frequencies of Cytochrome P450 2B6 polymorphisms in four southern Chinese populations.METHODS: DNA was obtained from blood samples from Han Chinese from Hong Kong and thr... AIM: To investigate the genotype and allelic frequencies of Cytochrome P450 2B6 polymorphisms in four southern Chinese populations.METHODS: DNA was obtained from blood samples from Han Chinese from Hong Kong and three minority groups,the Wa, Bulang and Lahu from Yunnan in southern China. Genotyping was performed using real-time PCR and confirmed by direct sequencing.RESULTS: A total of 507 subjects from southern China were studied. Results showed there is a high prevalence of 516G 〉 T (34.5%) in ethnic Chinese compared to literature reports on other Asian populations and Caucasians. The frequency of the 516TT genotype is higher in the Hah majority (23.1%) than in three other ethnic minority groups (i.e., 7.4%, 9.1% and 15.8%) in southern China.CONCLUSION: This was the first study to document the spectrum of CYP2B6 allelic variants and genotypes in a southern Chinese population. The 516G 〉 T allele is associated with a defective metabolism of efavirenz (EFV), which therefore may predispose to drug toxicity.Treatment regimens for human immunodeficiency virus (HIV) and heroin addiction may need to be optimized in different populations because of the marked variability of the key metabolizing enzyme. 展开更多
关键词 Polymorphism ALLELE GENOTYPE ETHNICITY Discrimination PCR
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Effect of blood glucose variability on the outcome in patients with severe acute stroke 被引量:6
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作者 朱继文 李雯 +2 位作者 袁方 康涛 江文 《中风与神经疾病杂志》 CAS 2018年第12期1060-1063,共4页
Objective To explore the correlation of blood glucose variability with the outcome in patients with severe acute stroke.Methods This retrospective clinical study was performed on patients with severe acute stroke.Base... Objective To explore the correlation of blood glucose variability with the outcome in patients with severe acute stroke.Methods This retrospective clinical study was performed on patients with severe acute stroke.Based on the three months mRS score after discharge,they were divided into good outcome groups and poor outcome groups.The blood glucose on admission,mean blood glucose,blood glucose standard deviation,coefficient variation of blood glucose and other clinical data were compared between both groups.Multivariate logistic regression analysis was used to determine the independent predictors of poor outcome in patients with severe acute stroke.Results A total of 420 patients with severe acute stroke were included,207(49.3%)with good outcome groups,213(50.7%)with poor outcome groups.Multivariate logistic regression analysis showed that age,NIHSS score,GCS score,APACHEⅡscore,blood glucose standard deviation,coefficient of variation of blood glucose were independent predictors of poor outcome in patients with severe acute stroke on 3 months after discharge.Conclusion Blood glucose variability are the independent predictors of poor outcome of the three months after discharge in patients with severe acute stroke,the great range of glycemic excursion indicates poor outcome. 展开更多
关键词 STROKE SEVERE BLOOD GLUCOSE VARIABILITY Prognosis
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Spatial Variability of Nutrient Properties in Black Soil of Northeast China 被引量:124
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作者 ZHANG Xing-Yi SUI Yue-Yu +2 位作者 ZHANG Xu-Dong MENG Kai S. J. HERBERT 《Pedosphere》 SCIE CAS CSCD 2007年第1期19-29,共11页
A total of 1400 soil samples from the plow layer (0-20 cm) at an approximate interval of 5 km were collected in the autumn of 2002 over the entire black soil arable crops region to determine the spatial variability ... A total of 1400 soil samples from the plow layer (0-20 cm) at an approximate interval of 5 km were collected in the autumn of 2002 over the entire black soil arable crops region to determine the spatial variability of seven variables, such as total organic matter content (OMC), total N, total P, total K, alkali-dissolvable N (AN), available P (AP) and available K (AK), with classical statistics and geostatistical analysis across the entire black soil area in Northeast China. In nonsampled areas ordinary kriging was utilized for interpolation of estimated nutrient determinations. Classical statistics revealed highly significant (P ≤ 0.01) correlations with all seven of the soil properties, except for OMC with AP and total K with AK. In addition, using coefficients of variation, all soil properties, except for total K, were moderately variable. A geostatistical analysis indicated that structural factors, such as parent material, terrain, and water table, were the main causes of the spatial correlations. Strong spatial correlations were noted with OMC, total N, total P, AN, and AP, while they were moderate for total K and AK. The effective spatial autocorrelation of OMC, total N, total P, and AN ranged from 1 037 to 1353 km, whereas the ranges of total K, AP, and AK were only from 6 to 138 km. The fit of the experimental scmi-variograms to the theoretical models indicated that except for AN, kriging could successfully interpolate other six variables. Thns, the geostatistical method used on a large scale could accurately evaluate the spatial variability of most black soil nutrient properties in Northeast China. 展开更多
关键词 black soil China geostatistics analysis soil survey spatial variability
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Spatial Variability of Soil Organic Carbon Under Maize Monoculture in the Song-Nen Plain, Northeast China 被引量:19
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作者 WANG Zong-Ming , ZHANG Bai, SONG Kai-Shan, LIU Dian-Wei and REN Chun-Ying Northeast Institute of Geography and Agricultural Ecology, Chinese Academy of Sciences, Changchun 130012 (China) 《Pedosphere》 SCIE CAS CSCD 2010年第1期80-89,共10页
Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils... Soil organic carbon (SOC) and its relationship with landscape attributes are important for evaluating current regional, continental, and global carbon stores. Data of SOC in surface soils (0–20 cm) of four main soils, Cambisol, Arenosol, Phaeozem, and Chernozem, were collected at 451 locations in Nongan County under maize monoculture in the Song-Nen Plain, Northeast China. The spatial characteristics of soil organic carbon were studied, using geographic information systems (GIS) and geostatistics. Effects of other soil physical and chemical properties, elevation, slope, and soil type on SOC were explored. SOC concentrations followed a normal distribution, with an arithmetic mean of 14.91 g kg-1 . The experimental variogram of SOC was fitted with a spherical model. There were significant correlations between soil organic carbon and bulk density (r =-0.374**), pH (r = 0.549**), total nitrogen (r = 0.781**), extractable phosphorus (r =-0.109*), exchangeable potassium (r = 0.565**), and cation exchange capacity (r = 0.313**). Generally, lower SOC concentrations were significantly associated with high elevation (r =-0.429**). Soil organic carbon was significantly negatively correlated with slope gradient (r =-0.195**). Samples of the Cambisol statistically had the highest SOC concentrations, and samples of the Arenosol had the lowest SOC value. 展开更多
关键词 GEOSTATISTICS slope soil bulk density spatial distribution
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Spatio-temporal variability of periphytic protozoa related to environment in the Niyang River,Tibet,China 被引量:1
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作者 刘海平 叶少文 +6 位作者 杨学峰 郭传波 张惠娟 范丽卿 张良松 Sovan Lek 李钟杰 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第3期489-500,共12页
The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecolo... The Niyang River, a main tributary of the Yarlung Zangbo River, is an important and typical plateau fiver ecosystem in Tibet, China. At present, few studies have focused on its aquatic living resources and fiver ecology. In this study, the composition, abundance, and diversity of periphytic protozoa were investigated across four seasons from 2008 to 2009 to better understand their spatio-temporal patterns and relationship to the environment. Our investigation shows that periphytic protozoa in the Niyang River contained 15 genera, belonged to Tubulinea, Alveolata, Discosea and Rhizaria, Alveolata possessed most genera, up to nine, with highest share in abundance, exceeding 50%, Difflugia and Glaucoma were dominant genera. Moreover, four diversity indices of periphytic protozoa, including species richness, total abundance, Shannon-Wiener diversity index and Pielou's evenness index, displayed a significant descending trend as the seasons continued, in the order of winter, spring, summer and autumn; with a significant difference existing between winter and summer (or autumn) for Shannon-Wiener diversity index and species richness (P〈0.05). Four of these diversity indices also presented a V-shaped pattern between the upper middle course of the Niyang River and the confluence of the Niyang River and Yarlung Zangbo River, with the lowest value occurred in the middle course of the Niyang River. However, no significant variation was found through the Niyang River (P〉0.05). In addition, canonical correlation analysis (CCA) shows that the densities of Difflugia, Glaucomais, Enchelydium, Cyphoderia, and Enchelys correlate with water temperature, alkalinity, hardness, pH, and dissolved oxygen, respectively. Lastly, the relationship between periphytic protozoa diversity and the environmental factors of the Niyang River can be predicted using classification and regression trees (CART) annalysis, which suggests that the total abundance and Shannon-Wiener diversity index would be higher when the elevation is above 3 308 m. On the other hand, the Shannon-Wiener diversity index and Pielou's evenness index would be lower when pH and ammoniacal nitrogen have lower or higher values. Finally yet importantly, close attention should be paid to periphytic protozoa and its environment to ensure sustainable development of the Niyang River ecosystem. 展开更多
关键词 Tibetan Plateau Niyang River periphytic protozoa ENVIRONMENT spatio-temporal dynamic
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Effect of hydrological variability on diatom distribution in Poyang Lake, China 被引量:2
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作者 QIAN Kuimei LIU Xia CHEN Yuwei 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期174-184,共11页
Poyang Lake is the largest freshwater lake in China, and it has a seasonal flooding cycle that significantly changes the water level every year. The aim of this paper was to explain how these hydrological changes infl... Poyang Lake is the largest freshwater lake in China, and it has a seasonal flooding cycle that significantly changes the water level every year. The aim of this paper was to explain how these hydrological changes influence diatom populations in Poyang Lake. The yearly hydrological cycle can be divided into 4 phases: low water-level phase, increasing water-level phase, high water-level phase and decreasing waterlevel phase. Variations in the abundance of planktonic diatoms were studied using quarterly monitoring data collected from January 2009 to October 2013. Generally, diatoms were dominant in Poyang Lake and accounted for more than 50% of the total phytoplankton biomass except in July 2009(26%) and January 2012(35%). Aulacoseira granulata and Surirella robusta were the predominant species in all four phases, and they accounted for 25.02% to 56.89% and 5.07% to 14.78% of the total phytoplankton biomass, respectively. A redundancy analysis(RDA) showed that changes in physico-chemical parameter were related to the water level, and changes in diatom biomass were related to nitrite levels and p H. These results indicate that changes in environmental parameters related to both seasonal variations and water-level fluctuations caused variations in diatom biomass and community composition in Poyang Lake. Furthermore, extreme hydrological events can have different influences on the diatom community composition in the main channel and lentic regions. This research provides data on the diatom variations in Poyang Lake and will be useful for establishing biological indicators of environmental change and protecting Poyang Lake in the future. 展开更多
关键词 diatom phytoplankton succession water-level changes Poyang Lake
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Spatial and Temporal Variability of Water Vapor Content during 1961-2011 in Tianshan Mountains,China 被引量:2
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作者 HU Wen-feng YAO Jun-qiang +1 位作者 HE Qing YANG Qing 《Journal of Mountain Science》 SCIE CSCD 2015年第3期571-581,共11页
Based on the climate factors data and surface vapor pressure (SVP) data of 44 weather stations in Tianshan Mountains during the years 1961-2011, this paper establishes a water vapor content (WVC) estimation model ... Based on the climate factors data and surface vapor pressure (SVP) data of 44 weather stations in Tianshan Mountains during the years 1961-2011, this paper establishes a water vapor content (WVC) estimation model according to the relationship between monthly WVC of radiosonde and corresponding SVP and analyzes the spatial and temporal variability of WVC and their causes. The results show that the WVC is linearly and negatively related to the elevation and longitude (Vertical zonality and Longitude zonality), while it was not linearly related to the latitude. The westerly wind, geographical situation and sea level elevation composed complex surface conditions to influence the spatial distribution of WVC in the Tianshan Mountains. The Mann-Kendall (M-K) statistical test shows a significant increasing trend in the mean annual WVC in Tianshan Mountains during 1961- 2011(P 〈 0.001), with a rate of 0.23 mm/decade, and indicates an abrupt turning point in 1985 (P.〈0.001). Correlation analysis shows that the WVC are significantly correlated to the temperature, especially during the winter, but the summer WVC are significantly correlated to the precipitation. In addition, the North Atlantic Oscillation Index (NAOI) and the Arctic Oscillation Index (AOI) are significantly correlated to the winter WVC in the Tianshan Mountains. As a new Microwave radiometric profilers (MWRPs) instrument, the MP- 3000A provides continuous, real-time and high temporal resolution atmospheric profiles up to 10 km. In order to monitor water vapor and atmosphere profiles in Tianshan Mountains, an MP-3000A was established in Urumqi (43.8°N, 87.58°N) in May 2008. The results indicated that the MP-3oooA was applicable to this area, and the evolutionary process of water vapor and the WVC peak values of MP- 3000A were a strong signal for rainstorm and flood forecasts for Urumqi and the Tianshan Mountains. 展开更多
关键词 Water vapor content Spatial variability Temporal variability Microwave radiometers Tianshan Mountains
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Spatial Variation and Space Optimization of the Development of China’s Circular Economy
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作者 Li Ning 《Chinese Journal of Population,Resources and Environment》 2012年第2期51-59,共9页
China's circular economy is still at the initial stage, whose development has many difficulties and problems requir- ing immediate resolution theoretically and practically. Due to the differences of regions on the sc... China's circular economy is still at the initial stage, whose development has many difficulties and problems requir- ing immediate resolution theoretically and practically. Due to the differences of regions on the scale of land, endowment of resources, economic basis and cultural background, the devel- opmental levels and capabilities of circular economy are inevi- tably different. Based on establishing the indicator system for assessing the developmental level of regional circular economy, spatial variation of China's circular economy is measured by the quantitative measurement using principal component analysis, and the existing problems are also analyzed and discussed. On one hand, the differences of the development capability of the circular economy of different provinces (cities) are profound in China; (!)Difference between the first category (strong) and the second category (relatively strong) is 1.1264 points. Difference between the second category and the third category (relatively weak) is 0.3867 points. Difference between the third category and the fourth category (weak) is 1.0238 points. Differencebetween the tlrst category and the tourtla category reaches up to 2.0869 points. Average difference between the area where the developmental level of circular economy is relatively strong and the area where the developmental level of circular economy is relatively weak is 1.3617 points. (~)The differences of the dis- tribution of the areas, with different development capability of circular economy, which are located in the three economic regions of China, are also profound. The regions with a relatively strong development capability of circular economy are mainly located in the eastern economic area, which account for 22.58% of the whole regions, while only account for 12.90% in the middle and western economic areas. On the contrary, the regions with a relatively weak development capability of circular economy account for 48.39% in the middle and western area, while ac- count for 16.13% in the eastern area. On the other hand, among regions with different development capability of circular econ- omy, the regions with a relatively weak development capability of circular economy are in a dominant position, which accountfor 64.52% of all the provinces (cities), which indicates that the development of the China's circular economy still has a long way to go. Though certain achievements have been made in the development of China's circular economy, in general, there are still some obstacles to be tacked in the development of China's circular economy which require the economic, legal and administrative methods. 展开更多
关键词 circular economy spatial variation space optimiza-tion China
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Spatial Variability of Soil Organic Carbon and Related Factors in Jiangsu Province,China 被引量:21
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作者 CHUAI Xiao-Wei HUANG Xian-Jin +3 位作者 WANG Wan-Jing ZHANG Mei LAI Li LIAO Qi-Lin 《Pedosphere》 SCIE CAS CSCD 2012年第3期404-414,共11页
Soil organic carbon (SOC) plays a key role in the global carbon cycle.In this study,we used statistical and geostatistical methods to characterize and compare the spatial heterogeneity of SOC in soils of Jiangsu Provi... Soil organic carbon (SOC) plays a key role in the global carbon cycle.In this study,we used statistical and geostatistical methods to characterize and compare the spatial heterogeneity of SOC in soils of Jiangsu Province,China,and investigate the factors that influence it,such as topography,soil type,and land use.Our study was based on 24 186 soil samples obtained from the surface soil layer (0-0.2 m) and covering the entire area of the province.Interpolated values of SOC density in the surface layer,obtained by kriging based on a spherical model,ranged between 3.25 and 32.43 kg m 3.The highest SOC densities tended to occur in the Taihu Plain,Lixia River Plain,along the Yangtze River,and in high-elevation hilly areas such as those in northern and southwest Jiangsu,while the lowest values were found in the coastal plain.Elevation,slope,soil type,and land use type significantly affected SOC densities.Steeper slope tended to result in SOC decline.Correlation between elevation and SOC densities was positive in the hill areas but negative in the low plain areas,probably due to the effect of different land cover types,temperature,and soil fertility.High SOC densities were usually found in limestone and paddy soils and low densities in coastal saline soils and alluvial soils,indicating that high clay and silt contents in the soils could lead to an increase,and high sand content to a decrease in the accumulation of SOC.SOC densities were sensitive to land use and usually increased in towns,woodland,paddy land,and shallow water areas,which were strongly affected by industrial and human activities,covered with highly productive vegetation,or subject to long-term use of organic fertilizers or flooding conditions. 展开更多
关键词 industrial and human activities land cover land use soil type TOPOGRAPHY
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Therapeutic efficacy and safety rating of Tui-Pushing chest-back manipulation for children with cough variant asthma Therapeutic efficacy and safety rating of Tui-Pushing chest-back manipulation for children with cough variant asthma 被引量:4
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作者 ZHU Binye LI Xue 《Journal of Acupuncture and Tuina Science》 CSCD 2022年第3期187-192,共6页
Objective:To observe and evaluate the clinical efficacy and safety of using pediatric Tuina(Chinese therapeutic massage),Tui-Pushing chest-back manipulation,in treating children with cough variant asthma(CVA).Methods:... Objective:To observe and evaluate the clinical efficacy and safety of using pediatric Tuina(Chinese therapeutic massage),Tui-Pushing chest-back manipulation,in treating children with cough variant asthma(CVA).Methods:Seventy-two kids with CVA were divided into two groups using the random number table method,with 36 cases in each group.The control group received the conventional Tuina treatment,and the observation group received additional Tui-Pushing chest-back manipulation.The clinical efficacy and adverse reactions were observed and recorded for the two groups.Results:After three treatment courses,compared with the control group,the observation group showed advantages in the total effective rate,reducing the number and intensity of cough and improving the nature of cough(P<0.05).However,at the one-month follow-up,there were no significant differences between the two groups in these parameters(P>0.05).Regarding the adverse reaction rate,there was no significant between-group difference(P>0.05).Conclusion:It is effective and safe to use pediatric Tuina,Tui-Pushing chest-back manipulation,plus the conventional treatment protocol to treat CVA in children. 展开更多
关键词 TUINA Massage Pediatric Tuina Tui-Pushing Manipulation Point Danzhong(CV17) Feishu(BL13) Cough Variant Asthma Child Preschool
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Causal interactions between the cerebral cortex and the autonomic nervous system 被引量:2
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作者 YU XiaoLin ZHANG Chong ZHANG JianBao 《Science China(Life Sciences)》 SCIE CAS 2014年第5期532-538,共7页
Mental states such as stress and anxiety can cause heart disease.On the other hand,meditation can improve cardiac performance.In this study,the heart rate variability,directed transfer function and corrected condition... Mental states such as stress and anxiety can cause heart disease.On the other hand,meditation can improve cardiac performance.In this study,the heart rate variability,directed transfer function and corrected conditional entropy were used to investigate the effects of mental tasks on cardiac performance,and the functional coupling between the cerebral cortex and the heart.When subjects tried to decrease their heart rate by volition,the sympathetic nervous system was inhibited and the heart rate decreased.When subjects tried to increase their heart rate by volition,the parasympathetic nervous system was inhibited and the sympathetic nervous system was stimulated,and the heart rate increased.When autonomic nervous system activity was regulated by mental tasks,the information flow from the post-central areas to the pre-central areas of the cerebral cortex increased,and there was greater coupling between the brain and the heart.Use of directed transfer function and corrected conditional entropy techniques enabled analysis of electroencephalographic recordings,and of the information flow causing functional coupling between the brain and the heart. 展开更多
关键词 mental task autonomic nervous system cerebral cortex heart rate variability information flow
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Intratree Variability of Tensile Strength Parallel to Grain in Chinese Fir and I-214 Poplar from Plantation
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作者 XU Ming REN Haiqing LI Xiazhen 《Chinese Forestry Science and Technology》 2007年第3期40-44,共5页
The variation of tensile strength parallel to grain in Chinese fir and 1-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical... The variation of tensile strength parallel to grain in Chinese fir and 1-214 poplar wood from plantations was studied in this paper. Aaccording to the national standards The Testing Methods for Physical and Mechanical Properties of Wood (GB 1927 to 1943 -- 1991), the small clear wood samples were cut and tested, which represent the south and north of trees with heights of 1.3, 3.3, 5.3 and 7.3 m. The results showed: the tensile strength parallel to grain of the north wood was higher than that of south wood. ANOVA shows that the tensile strength parallel to the grain with height is of significant difference (at 0.05 level). 展开更多
关键词 Chinese fir (Cunninghamia lanceolata) 1-214 poplar (Populus × euramericana cv. tensile strength PARALLEL VARIABILITY
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Analysis of Heart Rate Variability in Chinese PLA Navy Global Visiting Task Group
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作者 ZHANG Yong-sheng CHU Li-yun GONG Ting 《Chinese Journal of Biomedical Engineering(English Edition)》 2014年第1期12-19,共8页
Objective: To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods:We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 ... Objective: To analyze the heart rate variability in Chinese PLA navy global visiting task group. Methods:We analyzed the heart rate variability in Holter in 77 men and 4 women for 5-15 days before voyage, and 65-75 and 115-125 days after voyage, and 29 men and 3 women for 5-15 days after having finished voyage. Results:NN50 and VLF were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P&lt;0.01). SDANN was lower in 77 men and 4 women for 115-125 days after voyage than that was 65-75 days after voyage (P&lt;0.01). SDNN, SDANN, SDNN index, RMSSD, NN50, PNN50,Triangular index, VLF, HLF, VAI and VLI were lower in 77 men and 4 women for 65-75 days after voyage than that was 5-15 days before voyage (P&lt;0.01).Conclusion: These findings suggest that voyage may reduce heart rate variability for a long time. 展开更多
关键词 VOYAGE heart rate variability global visiting
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