大豆珠柄传输组织的显微形态观察

大豆光合作用产物是以淀粉粒的形式暂时贮存在叶片和豆荚的叶绿体中,以后在特定的时期降解为可溶性糖(碳水化合物)转移到需要的部位。这种光合产物的转移主要是在植物的维管组织中实现。在大豆植株生长的鼓粒期和成熟期,豆荚中还原糖的含量明显高于叶片。但由于豆荚的叶绿素含量及     

心肌线粒体细胞色素氧化酶的图象分析

成年大鼠10只,随机分为实验组(6只)和正常对照组(4只)。实验组大鼠置入密封玻璃容器内,同时放人适量钠石灰。90分钟后,取出动物,麻醉后灌流固定,取左心室前外侧壁组织标本作超微细胞色素氧化酶反应,同时取正常对照组大鼠左心室前外侧壁相同部位标本作对照。细胞色素氧化酶孵育采用DAB结合铈基法,用亚铁氰化钾半还原的锇酸后固定取代电子染色。实验组和对照组标本处理、孵育反应,电镜观察和照相条件等均相同。结果分析随机取样,对两组动物的电镜照片的各50个线粒体结构和细胞色素氧化酶反应进行图象分析。分析参数包括每个线粒体的面积、周长,形状因子(圆形度),     

凋亡神经元线粒体超微结构的形态计量学分析

目的:观察并分析人大脑皮层凋亡神经元线粒体超微结构的形态计量学变化.方法:取21例脑外科手术患者的额叶大脑皮质超薄切片中的正常神经元和凋亡神经元的电镜照片各80张,分为对照组与凋亡组.采用形态计量学方法对两组神经元的细胞体、细胞核、线粒体及细胞质基质灰度进行分析.结果:与正常神经元相比,凋亡神经元线粒体的体密度、面密度、数密度、比膜面明显增大(P＜0.01),比表面无明显改变(P＞0.05),线粒体基质与细胞质基质灰度之差明显增大(P＜0.01).结论:凋亡神经元线粒体未发生明显肿胀或增生,但其内膜和嵴的面积明显增加,基质密度降低.     

新生鼠缺氧缺血性脑损伤线粒体形态及功能改变的研究

新生鼠缺氧缺血性脑损伤线粒体形态及功能改变的研究汤秀英周丛乐＊苗鸿才＊张烨柴立军（北京医科大学第一医院电镜室，＊儿科，北京１０００３４）围产期缺氧缺血性脑损伤（ｈｙｐｏｘｉｃ－ｉｓｃｈｅｍｉｃｂｒａｉｎｄａｍａｇｅ）（ＨＩＤ）是一种常见且致残率高的疾...     

肝豆状核变性线粒体超微结构的形态计量学分析

目的:比较肝豆状核变性(hepatolenticular degeneration,Wilson’s disease,WD)与正常肝脏肝细胞线粒体的形态计量学差异。方法:应用透射电镜观察两组肝组织中肝细胞内线粒体并应用图像分析软件计算线粒体的平均周长、平均面积、数密度等。结果:肝豆状核变性肝细胞线粒体平均周长(Bm)、平均面积(Am)均大于正常对照组线粒体,两者差异具有显著性(P0.05),数密度(Nv)差异无统计学意义。结论:肝豆状核变性线粒体发生显著肥大。     

大豆子叶细胞中变形质体的形成和发育过程

质体是植物细胞中特有的一种细胞器。原质体、白色体、叶绿体和有色体之间的发育有着密切的关系。变形质体是一类不规则形状的原质体,多呈哑铃形、马蹄形或杯状。前人曾在许多植物的多种组织中看到过变形质体。但是关于变形质体的作用和进一步发育趋势目前尚无一致的看法。本文采用常规透射电镜技术观察了大豆子叶细胞中变形质体的形成和发育途径。结果和讨论:开花后19天的大豆子叶细胞中有许多原质体。其中部分原质体呈圆球形(图1)。部分原质体呈哑铃形(图2)、马蹄形(图3)和环形。从三维空间进行分析,马蹄形质体是杯状质体的一个     

意蜂飞翔肌线粒体的细胞化学研究

昆虫飞行时高强度的氧呼吸代谢为脊椎动物类所不及。原因之一是昆虫具健全的飞翔肌,在肌纤维间充塞有大量而具丰富内膜的线粒体。内膜上排列着完整呼吸酶和ATP合成酶。细胞色素氧化酶(也称细胞色素aa_3)位于呼吸链的终端,在细胞呼吸及氧化磷酸化过程中起着重要的作用。本文以电镜细胞化学方法对意蜂(Apis mellisfera L.)工峰飞翔肌发育过程中的线粒体细胞色素氧化酶进行研究。结果表明,细胞色素氧化酶在意峰发育整个过程中都是存在的,但在不同时期反应的强弱有别。幼虫期只     

脊索瘤细胞溶酶体吞噬线粒体的透射电镜观察

脊索瘤细胞溶酶体吞噬线粒体的透射电镜观察刘冬娟徐彦平郭玉坤石玉秀（中国医科大学第二电镜室，沈阳１１０００１）石岩（沈阳军区第二○二医院）溶酶体是组织细胞胞质中常见细胞器的一种，它不仅能分解外源性有害物质和细胞内损坏或衰老的细胞器，而且在细胞的防御机能...     

人巨细胞病毒在人胚肺细胞内的形态发生研究

以人巨细胞病毒AD-169株感染人胚肺成纤维细胞20分钟后,在电镜下观察到病毒颗粒吸附和穿透过程。感染后18小时,细胞核内出现包涵体。包涵体内有空心的核衣壳、含有病毒核心的核衣壳和二个同心园状的核衣壳。并见到病毒核心样物正在嵌入到核衣壳内的不同阶段形态(图1)。这提示核内包涵体是病毒复制和装配的场所。核内成束的小管状结构,其直径与核衣壳相同,可能是核衣壳结构蛋白或其前体物质的不稳定形态(图2)。胞浆包涵体内除含有成熟病毒和致密体外,尚有许多吞噬溶酶体,空泡和肿洚的内浆网、线粒体等。胞浆包涵体范围以外的胞质内细胞器基本正常,很少病毒颗粒和致密体(图     

复杂结构薄壁异形零件数控加工技术初探

航空机载设备因为对重量和空间尺寸有严格的要求,用到了许多复杂结构薄壁异形零件,这些零件结构刚性差,形状不规则,多由复杂曲面组成,只能使用UG等三维软件数控编程加工.为合理加工复杂结构薄壁异形零件,从工艺方法、数控编程、仿真检测、工装夹具、切削参数等方面对此类零件的数控加工进行了初步探讨,总结了复杂结构薄壁异形零件数控加...     

Localization of Lesion Cells and Targeted Mitochondria Via Embedded Hydrogel Microsphere using Heat Transfer Microneedles

The localization of lesion cells and targeted regulation of organelle function can promote the lesion repair. However, conventional regulation is difficult to reach deep lesions and target mitochondria. In this study, dynamic spiral Mosaic technology is ued to construct heat transfer microneedles with spiral Mosaic micro/nano hydrogel microspheres (ST-needle), using molecular chain motion in response to heat stimulation to regulate the adhesion of non-oriented triblock polymer, as a dual delivery system for heat energy and biological factors. The ST-needle system use its physical property to accurately reach the deep lesions and transfer heat to the lesion cells. Heat activates the dynamic spiral Mosaic mechanism of the ST-needle system, removing the Mosaic state of hydrogel microspheres and realizing the arrival of heat and hydrogel microspheres into lesion together. Through the rapid inhibition of mitochondrial apoptosis by heat, and long-term induce mitophagy by hydrogel microspheres releasing biological factors, finally complete the synergistic targeted regulation of mitochondrial function. In vitro/vivo experiments show that ST-needle system can inhibit chondrocyte apoptosis more effectively (64.41% lower than conventional regulation). Based on dynamic spiral Mosaic technique and the synergistic regulation of heat and biological factors, the ST-needle system is a promising method for lesion repair.     

The Analysis of Frequency Reuse Irregular Patterns in Mobile Telephone Network

Some frequency reuse irregular patterns in radionetwork design are proposed,the characteristic and applica-tion measures of these patterns are analyzed.Then this paperaccounts that frequency reuse irregular patterns is a usefulway to impove spectrum efficiency and it is significative forartificial intelligence to be applied in this field.     

Statistics and Its Applications in Identification of Irregular Particles

Phase Doppler anemonetry(PDA)is very sensitive to the shape of testing particles,which is based on sphericity assumption and Mie‘s theory.In practice,there exists effectiveness of non-sphericity and the response of PDA system deviates from the theoretical prediction.In this paper,the statistic characteristics of PDA signal are analyzed and a method of inentifying and quantifying irregular particles is proposed.It is concluded that phase difference of PDA signal for irregular particles is an unbiased estimation for spherical particles.     

不规则LDPC码度分布的优化设计研究

针对非规则LDPC码的度分布优化,研究了差分进化算法,并利用差分进化算法得到了最大门限的度分布序列,同时在AWGN信道下,通过高斯近似方法得到了在该度分布对下的较精确的LDPC译码门限。通过仿真发现,在改进后的优化算法中的度分布对得到了更高的门限值。同时高斯近似还能应用到其他高效纠错码,对现代高效纠错码具有重要的指导意义。     

内梅花弹体的超声信号分析与处理方法

内梅花弹体其内壁结构相对复杂,动态超声无损检测过程中则会出现棱波和台阶波形成干扰信号,使其背景噪声相对复杂,使用滤波方法无法将这两种信号与伤信号分离。针对这一问题提出了基于滑动平均的动态包络提取方法来消除这两种干扰。试验证明了这种方法可以有效地将棱波与台阶波去除,在工件探伤过程中取得了良好的效果。     

Complementary Absorbing Star‐Shaped Small Molecules for the Preparation of Ternary Cascade Energy Structures in Organic Photovoltaic Cells

Two anthracene‐based star‐shaped conjugated small molecules, 5′,5″‐(9,10‐bis((4‐hexylphenyl)ethynyl)anthracene‐2,6‐diyl)bis(5‐hexyl‐2,2′‐bithiophene), HBantHBT, and 5′,5″‐(9,10‐bis(phenylethynyl)anthracene‐2,6‐diyl)bis(5‐hexyl‐2,2′‐bithiophene), BantHBT, are used as electron‐cascade donor materials by incorporating them into organic photovoltaic cells prepared using a poly((5,5‐E‐alpha‐((2‐thienyl)methylene)‐2‐thiopheneacetonitrile)‐alt‐2,6‐[(1,5‐didecyloxy)naphthalene])) (PBTADN):[6,6]‐phenyl‐C71‐butyric acid methyl ester (PC₇₁BM) blend. The small molecules penetrate the PBTADN:PC₇₁BM blend layer to yield complementary absorption spectra through appropriate energy level alignment and optimal domain sizes for charge carrier transfer. A high short‐circuit current (J_SC) and fill factor (FF) are obtained using solar cells prepared with the ternary blend. The highest photovoltaic performance of the PBTADN: BantHBT :PC₇₁BM blend solar cells is characterized by a J_SC of 11.0 mA cm^?2, an open circuit voltage (V_OC) of 0.91 V, a FF of 56.4%, and a power conversion efficiency (PCE) of 5.6% under AM1.5G illumination (with a high intensity of 100 mW^?2). The effects of the small molecules on the ternary blend are investigated by comparison with the traditional poly(3‐hexylthiophene) (P3HT):[6,6]‐phenyl‐C61‐butyric acid methyl ester (PC₆₁BM) system.     

寄生分形多三角形结构在多频天线领域的应用推广

将寄生分形多三角形结构(Triangular Shaped Fractal Parasitic Elements,TSFPE)进行了改进和应用推广,提出一种基于TSFPE 的新型双频段振子天线,其具体结构为在振子天线的顶端两边对称地加载多个分形三角形。振子天线两臂控制低频段的辐射,而所加载的TSFPE 控制高频段的辐射。仿真和实测结果表明,天线在两个频段都具有良好的性能。新型天线结构的研制成功丰富了多频天线的种类,验证了TSFPE 在多频天线领域应用推广的可行性。该研究还将为TSFPE 在多频天线领域的进一步应用推广提供参考。     

异形瓷件的平封工艺

主要介绍了同结构异形陶瓷在烧成过程中发生塌陷变形的程度不同,所造成的封接强度也不同,分析并查找原因,采取有效的措施,使成品率大大提高,封接强度也很高.     

Coordinating Biointeraction and Bioreaction of a Nanocarrier Material and an Anticancer Drug to Overcome Membrane Rigidity and Target Mitochondria in Multidrug‐Resistant Cancer Cells

Multidrug resistance (MDR) is a main cause of chemotherapy failure in cancer treatment. It is associated with complex cellular and molecular mechanisms including overexpression of drug efflux transporters, increased membrane rigidity, and impaired apoptosis. Numerous efforts have been made to overcome efflux transporter‐mediated MDR using nanotechnology‐based approaches. However, these approaches fail to surmount plasma membrane rigidity that attenuates drug penetration and nanoparticle endocytosis. Here, a “one‐two punch” nanoparticle approach is proposed to coordinate intracellular biointeraction and bioreaction of a nanocarrier material docosahexaenoic acid (DHA) and an anticancer prodrug mitomycin C (MMC) to enhance mitochondrion‐targeted toxicity. Incorporation of DHA in solid polymer‐lipid nanoparticles first reduces the membrane rigidity in live cancer cells thereby increasing nanoparticle cellular uptake and MMC accumulation. Subsequent intracellular MMC bioreduction produces free radicals that in turn react with adjacent DHA inducing significantly elevated mitochondrial lipid peroxidation, leading to irreversible damage to mitochondria. Preferential tumor accumulation of the nanoparticles and the synergistic anticancer cytotoxicity remarkably inhibit tumor growth and prolonged host survival without any systemic toxicity in an orthotopic MDR breast tumor model. This work suggests that combinatorial use of biophysical and biochemical properties of nanocarrier materials with bioreactive prodrugs is a powerful approach to overcoming multifactorial MDR in cancer.