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1.  Studies on mineral ion absorption by plants  
   R. E. White《Plant and Soil》,1972年第36卷第1-3期
   Summary The relative yield response and phosphate uptake ofS. humilis, P. atropurpureus andD. intortum, grown on a very deficient soil, enriched with phosphate, were measured at four successive harvests during 42 days growth under controlled environmental conditions. Except at the first harvest (19–21 days), the relative yields ofS. humilis andP. atropurpureus at P0 were identical, and slightly greater than that ofD. intortum; the relative response to applied phosphate was similar for the three species, up to the maximum yield attained. The higher relative yield ofD. intortum, at harvest 1, reflected the influence of a higher initial phosphate concentration in the small Desmodium seedling, compared toS. humilis andP. atropurpureus. The mean absorption rate for phosphate 
$$\overline {\left( {AR} \right)} $$
ofD. intortum, and to a lesser degreeS. humilis andP. atropurpureus, showed two distinct maxima: an initial peak at low soil activities (0.3 — 3μM P), and a second at higher soil activities (37–43μM P) when maximum yield had been attained, and luxury accumulation of phosphate appear to occur. The initial peak in 
$$\overline {AR} $$
was followed by a decline (significant (P=0.05) forD. intortum) at soil phosphate activities corresponding to maximum yield, suggesting that the rate of absorption by the roots was influenced by the demand for phosphate created within the growing plant. Mean absorption rates and relative growth rates 
$$\overline {\left( {RGR} \right)} $$
, averaged over all phosphate levels, fell in the orderD. intortum >S. humilis >P. atropurpureus. Conversely, the efficiency of phosphate utilization by the plant, which may be expected to be greater in plants of low RGR, fell in the orderP. atropurpureus >S. humilis >D. intortum, and so counteracted the lower 
$$\overline {AR} $$
ofP. atropurpureus, and to a lesser extent,S. humilis. However,S. humilis had the advantage of a lower retention of phosphate in the root system, compared toP. atropurpureus, due to a relatively greater shortage of nitrogen in the tops when grown on symbiotically-fixed nitrogen.    

2.  Chromosomal replication in Drosophila virilis  
   M. Steinemann《Chromosoma》,1981年第82卷第2期
   DNA fiber autoradiography was used to determine parameters underlying the DNA replication of the eukaryotic chromosome in Drosophila diploid brain cells in organ culture. The average rate of fork movement, estimated from 4 different labelling intervals, is 0.35 μm/min at 25 ° C. Of the tandem arrays 93% show patterns which are compatible with bidirectional replication, 7% show unidirectional replication. The unidirectional mode of replication is interpreted as being a consequence of the experimental schedule (using hot-cold pulse labelling) combined with the occurrence of termination signals. — Some autoradiograms showed the expected two grain tracks of different densities; others showed only a high density track. The latter were most prominent in arrays of short replicons (<10 μm) which correlate with replicating satellite sequences. — The majority of replicons fall into size classes < 100 μm. The frequency distribution is skewed towards larger replicon sizes; it spans 2–238 μm, has a mean of ˉx = 35.6 μm and a median of 
$$\tilde x$$
= 21.0 μm. If the distribution is corrected for supposed satellite replicons, the median increases to 
$$\tilde x$$
= 31.0 μm. — In experiments using warmhot pulse labelling, arrays were scored which must have been a consequence of fixed termination signals. Furthermore, grain tracks diverging from weak labelled centers often have different lengths, indicating that these replicons contain two diverging replicating sections of unequal length. Presented to Professor Dr. Wolfgang Beermann on the occasion of his 60th birthday with my best wishes    

3.  Estimating Stem Volume Using QuickBird Imagery and AIIometric Relationships for Open Populus xiaohei Plantations  
   Xiao-Qing Wang Zeng-Yuan Li Xing-E Liu Guang Deng Ze-Hui Jiang《植物学报(英文版)》,2007年第49卷第9期
   There has been a great deal of interest in studying the crown of trees using remote sensing data. In this study, crown width was extracted from high-resolution QuickBird images for open Populus xiaohei plantations. Regression models for predicting the individual stem volumes of Populus xiaohei were established using extracted crown width, as well as estimated tree parameters (i.e. diameter at breast height [DBH] and tree height) as predictors. Our results indicated that crown width could be accurately extracted from QuickBird images using a multi-scale segmentation approach with a mean relative error of 5.74%, especially for wide-spacing stands. Using either extracted crown width alone or with estimated DBH and tree height can successfully estimate individual stem volume of Populus xiaohei with the R2 value ranging from 0.87 to 0.92 depending on different model forms. In particular, the two second-order polynomial models (model 2 and model 6), based on QuickBird image-derived crown widths and estimated DBH and tree heights, respectively, were the best at describing the relationship between stem volume and tree characteristics.    

4.  Estimating Stem Volume Using QuickBird Imagery and Allometric Relationships for Open Populus xiaohei Plantations  
   Xiao-Qing Wang Ze-Hui Jiang Research Institute of Wood Industry  Chinese Academy of Forestry  Beijing   ChinaZeng-Yuan Li Guang Deng Research Institute of Forest Resource Information Techniques  Chinese Academy of Forestry  Beijing   ChinaXing-E Liu International Centre for Bamboo and Rattan  Beijing   China《Acta Botanica Sinica》,2007年第9期
   There has been a great deal of interest in studying the crown of trees using remote sensing data.In this study,crownwidth was extracted from high-resolution QuickBird images for open Populus xiaohei plantations.Regression modelsfor predicting the individual stem volumes of Populus xiaohei were established using extracted crown width,as well asestimated tree parameters(i.e.diameter at breast height[DBH]and tree height)as predictors.Our results indicated thatcrown width could be accurately extracted from QuickBird images using a multi-scale segmentation approach with a meanrelative error of 5.74%,especially for wide-spacing stands.Using either extracted crown width alone or with estimatedDBH and tree height can successfully estimate individual stem volume of Populus xiaohei with the R~2 value ranging from0.87 to 0.92 depending on different model forms.In particular,the two second-order polynomial models(model2 andmodel 6),based on QuickBird image-derived crown widths and estimated DBH and tree heights,respectively,were the bestat describing the relationship between stem volume and tree characteristics.    

5.  Estimation of larval dry weight of Chaoborus americanus  被引次数:1
   Joseph A. Traina  Carl N. von Ende《Hydrobiologia》,1992年第228卷第3期
   A method for estimating larval dry weight as a function of tracheal front air sac length and instar was developed for second, third, and fourth instar Chaoborus americanus using linear regression analysis. The following equation: 
$$W^{0.5}  = (L - a)/b,$$
where W = larval dry weight (μg), L = front air sac length (mm), a = the y-intercept, and b = the slope provided accurate estimates of larval dry weight for three C. americanus populations. No detectable change in size occurred in the air sacs of larvae preserved for one year in 5% formalin. This indicates that air sacs can be used to accurately estimate larval dry weight for preserved as well as living specimens.    

6.  基于细胞色素b基因序列的鲤科鱼类系统发育研究(鱼纲: 鲤形目)  被引次数:17
   何舜平  刘焕章  陈宜瑜  Tsuneo Nakajima  钟扬《中国科学C辑》,2004年第34卷第1期
   鲤科是鱼类最大的科, 在中国淡水鱼类组成中鲤科鱼类的成分占一半以上. 鲤科鱼类的演化过程代表了东亚淡水鱼类的整体演化过程. 为探讨东亚鲤科鱼类系统发育关系, 共分析了包括18种新测序列在内的54种鲤科鱼类细胞色素b基因的全序列. 分析的物种涵盖了鲤科鱼类的12个亚科并对问题较多的亚科(Danioninae)和雅罗鱼亚科(Leuciscinae)进行了广泛的采样. 系统发育树的建立使用了多种方法, 包括邻接法、最大简约法和最大似然法. 亚口鱼科(Catostomidae)的胭脂鱼(Myxocyprinus asiaticus)被指定为外类群, 3种方法所得结果非常相似, 并支持一些亚科的单系性, 如鲌亚科(Cultrinae)、鯝亚科(Xenocyprinae)、鮈亚科(Gobioninae)(包括鳅鮀亚科Gobiobotinae). 从分子水平上证明亚科不是一个单系类群, 雅罗鱼亚科被分为两个互不相关的类群; 东亚雅罗鱼群与鲌亚科和鯝亚科形成一单系类群; 而欧洲、西伯利亚、北美的雅罗鱼形成另一个单系群. Howes所定义的鲤亚科在NJ树和ML树中得到有力的支持并位于系统树的基部. 高体鳑鲏(Rhodeus sericeus)代表的鳑鲏亚科的系统位置没有得到解决. 显示鲤科鱼类可分为3个大的类群并与其3个进化阶段相对应: 老第三纪类群包含亚科的东南亚种类和Howes的鲤亚科; 北方冷水性类群包含北方雅罗鱼、鮈亚科和鳑鲏; 东亚类群包含鲌亚科、鯝亚科、雅罗鱼东亚种类和亚科东亚种类. 老第三纪类群代表鲤科鱼类的原始阶段, 北方冷水性类群对应于鲤科鱼类对全球变冷的反应, 而东亚类群则显示青藏高原急剧隆升后, 在东亚季风气候条件下鲤科鱼类的大量分化.    

7.  Visualization of chromatin folding patterns in chicken erythrocytes by atomic force microscopy (AFM)  
   QIANRUOLAN ZHENGXIALIU 等《细胞研究》,1997年第7卷第2期
   The organization of the higher order structure of chromatin in chicken erythrocytes has been examined with tapping-mode scanning force microscopy under conditions close to their native envirinment.Reproducible highresolution AFM images of chromatin compaction at several levels can be demonstrated.An extended beads-on-astring (width of - 15-20nm,height of - 2-3nm for each individual nucleosome) can be consistently observed.Furthermore,superbeade (width of - 40nm,height of - 7nm) are demonstrated.Visualization of the solenoid conformation at the level of 30nm chromatin fiber is attained either by using AFM or by using electron microscopy.In addition,tightly coiled chromatin fibers (- 50-60nm and - 90-110nm) can be revealed.Our data suggest that the chromatin in the interphase nucleus of chicken erythrocyte represents a high-order conformation and AFM provides useful high-resolution structural information concerning the folding pattern of interphase chromatin fibers.    

8.  Topography and functional information of plasma membrane  
   DeLan Sun  JianMin Chen  YanMei Song  ChuanFeng Zhu  GeBo Pan  LiJun Wan《Science China. Life sciences》,2008年第51卷第2期
   By using atomic force microscope (AFM), the topography and function of the plasmalemma surface of the isolated protoplasts from winter wheat mesophyll cells were observed, and compared with dead protoplasts induced by dehydrating stress. The observational results revealed that the plasma membrane of living protoplasts was in a state of polarization. Lipid layers of different cells and membrane areas exhibited distinct active states. The surfaces of plasma membranes were unequal, and were characterized of regionalisation. In addition, lattice structures were visualized in some regions of the membrane surface. These typical structures were assumed to be lipid molecular complexes, which were measured to be 15.8±0.09 nm in diameter and 1.9±0.3 nm in height. Both two-dimensional and three-dimensional imaging showed that the plasmalemma surfaces of winter wheat protoplasts were covered with numerous protruding particles. In order to determine the chemical nature of the protruding particles, living protoplasts were treated by proteolytic enzyme. Under the effect of enzyme, large particles became relatively looser, resulting that their width was increased and their height decreased. The results demonstrated that these particles were likely to be of protein nature. These protein particles at plasmalemma surface were different in size and unequal in distribution. The diameter of large protein particles ranged from 200 to 440 nm, with a central micropore, and the apparent height of them was found to vary from 12 to 40 nm. The diameter of mid-sized protein particles was between 40―60 nm, and a range of 1.8―5 nm was given for the apparent height of them. As for small protein particles, obtained values were 12―40 nm for their diameter and 0.7―2.2 nm for height. Some invaginated pits were also observed at the plasma membrane. They were formed by the endocytosis of protoplast. Distribution density of them at plasmalemma was about 16 pits per 15 μm2. According to their size, we classified the invaginated pits into two types―larger pits measuring 139 nm in diameter and 7.2 nm in depth, and smaller pits measuring 96 nm in diameter and 2.3 nm in depth. On dehydration-induced dead pro-toplasts, the degree of polarization of plasma membranes decreased. Lipid molecular layers appeared relatively smooth, and the quantity of integral proteins reduced a lot. Invaginated pits were still de-tectable at the membrane surface, but due to dehydration-induced protoplast contraction, the orifice diameter of pits reduced, and their depth increased. Larger pits averagely measuring 47.4 nm in di-ameter and 31.9 nm in depth, and smaller pits measuring 26.5 nm in diameter and 43 nm in depth at average. The measured thickness of plasma membranes of mesophyll cells from winter wheat examined by AFM was 6.6―9.8 nm, thicker in regions covered with proteins.    

9.  040401.gif (395 bytes)属Willowsia及中国分布种(弹尾目:长科)  
   石玺   陈建秀《昆虫分类学报》,2004年第26卷第4期
   本文讨论了柳(虫兆)属Willowsia及其中国的种类,并描述了广西1新种,Willowsiaguangxiensis, sp. Nov..该种与越南的W. Pseudosocia Stach 1965最为接近,如鳞片具小棘、胸部和腹部大毛数量多等.但在体色、触角及足上有鳞片、腹管及身体上的毛序等方面有别于后者.正模♂,广西百色市田林县岑王老山,海拔2050米,1999-Ⅶ-03,采集号8698-19,陈建秀,王松杰采.副模6♂♂, 8681-20(2),8681-28(3), 8681-33(3), 8681-35(2), 8681-38(1), 8685-12; 110♀♀, 8678-20, 8681-20~42,8685-7,8685-1~34, 8690-1~10, 8690-26, 8690-32, 8690-34, 8698-24, 海拔1 350~2 050米,1999-Ⅶ-31~Ⅷ-03,其它同正模.模式标本保存存在南京大学生物科学与技术系.    

10.  细菌群体异质性对生长动态过程的影响及其表征  被引次数:1
   张怀强  卢丽丽  阎雪岚  高培基《中国科学C辑》,2007年第37卷第2期
   在经典的表征群体生长的Logistic方程中, 假定群体中每个个体都是同质的. 解方程时的初值仅限定为N(t0) = N0, 因此, 对N0相同而生理状态不同的接种物的生长动态不能区分. 事实上, 在菌群生长的任一时刻, 只有一定比例的细胞在进行分裂(设为θ), 这样, 不仅由N, 而且实际上由Nθ 共同决定. 因此, 解方程的初值条件还应加入θ (t0) = θ0, 而这又被在构建生长方程时所忽略, 但这一附加条件使Logistic方程的求解甚为复杂. 基于细菌生长过程的瞬时生长速率Vinst的时间过程曲线都呈Gauss分布形状这一特点, 在用瞬时生长速率成功地表征限制性条件下区分群体生长阶段的基础上, 进一步用Gauss分布近似函数表达式以求得异质性群体的生长参数, 这些参数可真实地表征不同生理状态细菌群体的生长动态, 为微生物学基础研究和在生物工程等方面的应用提供了一个新方法. 在此基础上提出了一个估算细菌群体生长延迟期和群体倍增时间的新方法.    

11.  The structure of the nucleosome core particle of chromatin in chicken erythrocytes visualized by using atomic force microscopy  
   Zhao H  Zhang Y  Zhang SB  Jiang C  He QY  Li MQ  Qian RL《Cell research》,1999年第9卷第4期
   The structure of the nuclosome core particle of chromatin in chicken erythrocytes has been examined by using AFM.The 146 bp of DNA wrapped twice around the core histone octamer are clearly visualized.Both the ends of entry/exit of linker DNA are also demonstrated.The dimension of the nucleosome core particles is - 1-4 nm in height and - 13-22 nm in width.In addition,superbeads (width of - 48-57 nm,height of - 2-3 nm )are occasionally revealed,two turns of DNA around the core particles are also detected.    

12.  Density Effects on Plant Height Growth and Inequality in Sunflower Populations  被引次数:4
   Sa Xiao Shu-Yan Chen Lu-Qiang Zhao Gang Wang《Journal of Integrative Plant Biology》,2006年第48卷第5期
   Comparisons between competing and non-competing sunflower (Helianthus annuus L.) populations demonstrate pronounced effects of density on plant height growth, height-to-crown width ratio, and s popuiaUon's height inequality. In the present study, non-destructive measurements of height and the prolected crown area of sunflower plants were taken at seven times from emergence to fruit maturation in even-aged monospeclflc stands with initial densities of 1, 4, 16, and 64 plants/m^2. The mean height of populations Increased and then decreased with increasing population density; the height Inequalities of uncrowded populations decreased during stand growth, whereas the height inequaiiUes of crowded popuisUons decreased first and then increased during stand development. The interindlvidual relationships between the relative height growth rate and height within uncrowded populations became significantly negative during population growth, whereas these relationships were negative first and then became positive during the development of crowded populations. In the uncrowded populations, the static Interindlvldual relationship between height-to-crown width ratio and volume was positive, whereas for the crowded population these relationships became negative with increasing competition for light. The data suggest that the plastic responses of plant height and height-to-crown width ratio to light competition will become more Intense with increasing competition Intensity. The results of the present study argue strongly for the Importance of size-dependent Individual-level plastic responses due to size-asymmetric light competition In generating the variations in population height inequality.    

13.  A New Species of the GenusThermophis (Serpentes:Colubridae) from Shangri-La,Northern Yunnan,China, with a Proposal for an Eclectic Rule for Species Delimitation  
   Lifang PENG  ;Changhu LU  ;Song HUANG  ;Peng GUO  ;Yaping ZHANG《亚洲两栖爬行动物研究(英文版)》,2014年第4期
   The hot-spring snakes,Thermophis, were previously known only from the Tibet Autonomous Region and Western Sichuan, China. During the past two years, three adult hot-spring snakes (2 females, 1 male) were sampled in Shangri-La, northern Yunnan, China, thus expanding their known distribution region towards the southeast. This site is the southeastern-most corner of the Tibetan Plateau and the southernmost tip of the Hengduan Mountains (Mts.). Phylogenetic analysis of mitochondrial (mt) and nuclear (n) DNA segments suggested that the three specimens belong to the genus ofThermophis. Morphologically, the new species is more similar toT. zhaoermii. However, it is distinguished fromT.zhaoermiiin the number of maxillary teeth (15), distance between the two eyes/head width, rostral width/height, mental width/height, in one character limited to female: head width/length, and in four characters restricted to male: occurrence of the reduction from 10 to 8 (8 to 6, 6 to 4) scales in each dorsal row on the tail. There are differences in morphology, genetics (mtDNA, nDNA), and geography between the putative new species andT.zhaoermii,the new species meets our proposed eclectic and feasible "four-differences" rule.    

14.  人类脂肪来源成体干细胞体外培养的生物学特征研究及供体年龄对其增殖的影响  
   雷磊  廖威明  盛璞义  傅明  何爱珊  黄纲《中国科学C辑》,2007年第37卷第2期
   通过研究人类脂肪组织来源成体干细胞(human adipose tissue derived adult stem cells, hADAS细胞)体外培养的生物学特征及供体年龄对其生长增殖的影响, 为其作为组织工程学研究和应用的种子细胞提供实验室研究基础. 取不同年龄组志愿者(<20岁、21~40岁、41~60岁和>61岁), 手术中切除少量皮下脂肪组织, 酶消化法分离细胞, 体外培养, 传至20代. 取培养第3代细胞, 流式细胞仪检测细胞表面抗原标记物(CD29, CD34, CD44, CD45, CD49d, HLA-DR, CD106)和细胞周期. 细胞培养传20代后进行细胞染色体组分析. MTT法分别检测各年龄组不同时间点吸光值, 绘制生长曲线, 根据公式换算人类脂肪来源干细胞倍增时间(time doubling, TD). 结果显示: 酶消化法自皮下脂肪组织分离细胞, 体外培养hADAS细胞, 流式细胞仪检测示CD29+, CD34-, CD44+, CD45-, CD49d±, HLA-DR-, CD106-; G1期占90%(P10代); P20细胞染色体组分析显示为正常染色体, 未见异常染色体, 保持遗传稳定. 绘制细胞生长曲线, <20年龄组TD为(11.22±0.73)h, 21~40年龄组TD为(11.14±0.76)h, 两组之间P >0.05, 无显著性差异; 41~60年龄组TD为(13.18±1.58)h , >61年龄组TD为(13.11±0.83)h, 两组之间P>0.05, 无显著性差异. <20年龄组TD与>61年龄组TD显著性差异, P<0.05. 说明hADAS细胞可方便地取材于皮下脂肪组织, 体外培养遗传特性稳定, 生长活跃, 青年组生长活性强于老年组, 可以作为组织工程学种子细胞的新来源.    

15.  温度对扬子鳄卵野外孵化的影响  被引次数:6
   何利军  王小明  丁由中  邵民  汪国宏  谢万树《动物学报》,2002年第48卷第3期
   Influence of temperature on egg incubation of the wild Chinese alligator was studied during the summer seasons of 1999 and 2000(July to October and August to September,respectively)at three observation sites, Zhuangtou of Xuanzhou County,Shuangkeng and Zhongqiao of Jingxian county, Anhui Province. One nest at each of the above sites was monitored, bearing 19,17 and 19 eggs,respectively. According to the width of the band on the eggs, we estimated the dates that the eggs were laid. We recorded both the nest temperature and atmosphere temperature with an automated temperature data logger (HOBO Temp) during the whole observation period.We found that the average nest temperature maintained around 25 26℃ during incubation throughout day and night,within over two thirds of time in each day the nest temperature being higher than the atmosphere temperature. Analysis of our data revealed that alligator nests have buffering effect on the inside temperature. Higher nest temperature (27 30℃)increased the hatching rate. It was also noticed that the hatching rate varied considerably from site to site(between 0 100%). We conclude that climate is an important factor influencing egg hatching in the wild, and prolonged rainy season which caused large temperature fluctuation can decrease the hatching rate of the alligator eggs.    

16.  前牙切角缺损嵌体修复远期疗效观察  
   高素娟《上海生物医学工程》,1992年第2期
   作者采用混合型嵌体修复前牙切角缺损120例,经过20年随访,复查24例,28个修复体,19个完好,无松动,边缘密合,功能良好,唯唇面充填材料磨损、变色,影响美观。修复时间最长17年,最短3年,远期疗效良好。本文结合临床实践,对前牙切角缺损的适应证、洞型设计、牙体制备、蜡型制作及充填材料进行了讨论。    

17.  米氏球角跳属中国新纪录及一新种(弹尾目,球角跳科)  
   吴东辉  谢荣栋《动物分类学报》,2007年第32卷第2期
   报道了球角跳科在中国的1新纪录属"米氏球角跳属",并描述了1新种,新种命名为鞍山米氏球角跳Mitchellania anshanensis sp.nov.鞍山米氏球角跳与描述自西伯利亚的M.subhorrida Babenko,1994相似,两者的主要区别在于:新种体长仅0.8mm,腹部第5节背面p1毛之间体表颗粒数量为17~20,触角第4节腹面有20~25个弯曲且顶端膨大的短小感觉毛,爪部生有1内齿,但无侧齿,胸部第2和第3节背面感觉毛短小精巧,腹部第1~3节背面感觉毛与普通刚毛长度相同;M.subhorrida体长达到1.5mm,腹部第5节背面p1毛之间体表颗粒数量为8~10,触角第4节腹面弯曲且顶端膨大的短小感觉毛数量范围为30~35个,爪部生有1内齿和1侧齿,胸部第2节、腹部第1~3节背面感觉毛与普通刚毛长度相同,胸部第3节和腹部第2节背面感觉毛短小粗壮.模式标本保存在中国科学院上海植物生理生态研究所.    

18.  c-SRC基因敲减降低宫颈癌HeLa细胞活性及磷酸化的信号转导与转录激活子-3蛋白表达  
   Chen JX  Xu LL  Wu SJ  Liu HY  Wang JL  Zou T《生理学报》,2011年第63卷第3期
   本文旨在研究c-SRC蛋白对人宫颈癌HeLa细胞的活性及对磷酸化的信号转导与转录激活子-3(phosphorylated signal transducer and activator of transcription-3,p-STAT3)表达的影响。人宫颈癌HeLa细胞转染c-SRC RNA干涉质粒后,分别用RT-PCR和Westernblot检测细胞内c-SRC mRNA和蛋白的表达;用MTT比色法观察c-SRC敲减后细胞的活性;用流式细胞仪检测细胞周期;同时检测细胞内p-STAT3的表达情况。转染c-SRC RNA干涉质粒后,HeLa细胞内c-SRC mRNA和蛋白的表达显著降低;在转染c-SRC RNA干涉质粒24、48、72及96h后,细胞活性分别下降了23.1%、29.3%、38.6%和45.0%(均P<0.05)。转染c-SRC RNA干涉质粒24、48、72及96h后,HeLa细胞S期细胞数分别下降了5.6%、10.0%、15.2%和19.9%(均P<0.05)。敲减c-SRC后,细胞内p-STAT3的含量也显著下降。与对照组相比,STAT3抑制剂Piceatannol处理细胞24、48、72...    

19.  木毒蛾核型多角体病毒形态结构及理化性质的研究  被引次数:2
   彭贵洪  张立人  陈棣华  陈尧顺《Virologica Sinica》,1995年第10卷第2期
   木毒蛾核型多角体病毒属昆虫杆状病毒科,核型多角体病毒属,多粒包埋型。在扫描电镜下,多角体呈不规则多面体,大小下一,平均直径为1.4μm,病毒粒子杆状,大小约为394×56nm,经SDM-PAGE分析,病毒多角体蛋白分子量为30.5kD,病毒粒子结构蛋白由19条多肽组成,分子量范围在88-17kD之间。多角体富含Glu、Val、Leu、而Cys、Met、和His含量较少。其酸碱氨基酸之比为1.26。病毒核酸为一环状DNA,长度约为38μm,经HindⅢ、PstⅠ、EcoRⅠ和BglⅠ单酶切以及BamHⅠ+HindⅢ、BamHⅠ+PstⅠ、BamHⅠ+BgIⅠ和Xhol+EcoRⅠ双酶切分析,DNA总分子量约为71.6×10 ̄6Daltons。    

20.  股四头肌腱双束重建前交叉韧带的生物力学特性研究  
   王琦  张积华  张才龙  田少奇  孙康  黄洪杰  李永会《现代生物医学进展》,2011年第11卷第6期
   目的:探讨股四头肌腱的生物力学特性,为其能否应用于临床前交叉韧带(ACL)重建提供实验依据.方法:取32例新鲜尸体的1cm宽股四头肌腱,按其解剖结构分为两柬:股直肌、股内、外侧肌腱舍为A束,股中问肌腱为B束,用游标卡尺测量两束的宽度及厚度,然后将两束置于电子万能试验机上分别测其生物力学指标.结果:A 束厚度为4.39±1.72mm,宽度为8.19±1.18mm,生物力学强度为685.67±227.09N,抗拉强度为17.00±3.48Mpa;B束厚度为3.06±1.47mm,宽度为7.10±2.03mm,生物力学强度为435.04±205.80N,抗拉强度为13.16±4.02Mpa.A束生物力学强度与ACL比较,差异有统计学意义(p<0.05);B束生物力学强度与ACL比较,差异有统计学意义(p<0.05).结论:股四头肌腱的生物力学性能不能满足ACL双束重建的要求,其在临床上应用于ACL双束重建的价值有待于进一步的深入研究.
Abstract:
Objective: To investigate the biomechanics of the quadrieeps tendon and to provide theoretical basis for double-bundle reeonstruction of anterior cruciate iigament(ACL). Methods: 32 quadriceps tendons (width lena) taken from fresh cadaver were dissected into 2 bundles according to the anatomy, one bundle including rectus femoris, vastus medialis and vastus lateralis was named A bundle and the other was named B bundle. The width and thickness of the A and B bundle were detected respectively with a Vernier caliper and the biomechanics were determined by WDW-30 election universal testing machine. Results: The thickness, width, ultimate load and ultimate tensile strength of bundle A were 4.39± 1.72mm, 8.19± 1.18mm, 685.67± 227.09 N and 17.00± 3.48 Mpa respectively, while for bundle B,which were 3.06± 1.47 ram, 7.10± 2.03mm: 435.04±205.80 N and 13.16± 4.02 Mpa. There was difference between bundle A and the ACL (p<0.05). Conclusion: The ultimate load ofbundle A was much lower than the the ACL and bundle Bwas also lower than the ACL.    

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