Alkaline phosphatase activity in the osteoclasts induced by experimental tooth movement.

The localization of alkaline phosphatase (Alpase) activity in the osteoclasts was examined cytochemically. Alpase activity was located in the basolateral membrane in mature osteoclasts having ruffled borders and clear zones, and also in the basolateral membrane in the osteoclasts lacking a ruffled border or a clear zone on the bone surface. But in the preosteoclasts situated away from the bone surface the enzyme activity was noted in the whole plasma membrane. These results suggest that the localization of Alpase activity may be altered in relation to the changes in morphology associated with the functional activity of the osteoclasts.     

Association of cytoskeletons with the Golgi apparatus: three-dimensional observation and computer-graphic reconstruction

The association of cytoskeletons with the Golgi apparatus (GA) in cultured 3Y1 cells was investigated by stereo electron microscopy of thick sections and computer-graphic reconstruction of serial thin sections. The 3-dimensional analysis has demonstrated that: 1) both microtubules (MT) and vimentin intermediate filaments (IF) were abundantly present in close vicinity to GA, and some of them were closely associated with GA; and 2) such GA-associated cytoskeletons were attached to GA either at their termini or at their lateral side. The present observations suggest that both MT and vimentin IF are responsible for maintaining the structural integrity of GA.     

重组RANK蛋白抑制破骨细胞活性的实验研究

目的研究重组RANK蛋白在体外实验中对破骨细胞的抑制作用。方法成骨细胞与RAW264.7细胞以4∶1比例混合培养6d,以抗酒石酸酸性磷酸酶(TRAP)染色鉴定后,加入3种浓度(10-4g/L、10-5g/L、10-6g/L)重组RANK蛋白,并设空白对照。3d后观察破骨细胞数目和形态,计数骨磨片吸收陷窝。结果混合培养6d后,体系中可见成熟破骨细胞出现。加重组RANK蛋白3d后,与对照组相比,各药物组TRAP阳性细胞个数、骨磨片吸收陷窝计数均明显减少。结论体外实验中重组RANK蛋白可以显著抑制破骨细胞活性及吸收功能。     

Use of taxol and collagenase for better three-dimensional visualization of microtubules in the enterocyte and Brunner's gland cell, with special reference to their relation to the Golgi apparatus

Cytoskeletal microtubules were visualized in the mouse duodenal mucosa by an improved immunofluorescence method using a microtubule-stabilizing reagent, Taxol, and collagenase as an enzymatic epitope retriever. The improvement in immunostaining was shown morphologically and statistically by comparing fluorescence intensities of specimens prepared with or without Taxol and collagenase treatment. In free cells in the epithelium and in the lamina propria, microtubules radiated from the gamma-tubulin-immunostained organizing center. Enterocytes and Brunner's gland cells double-stained with an anti-alpha-tubulin antibody and a lectin (Helix pomatia agglutinin, soybean agglutinin or Ulex europaeus agglutinin-I) showed that microtubules ran along the cell axis and were abundant between the Golgi apparatus and the apical surface. The microtubules appeared to provide a structural support to hold the Golgi apparatus in position and to act as railways for secretory granules, which are transported towards the apical surface. In addition, gamma-tubulin-like immunoreactivity was associated with the Golgi apparatus in the enterocytes. These results show that the method using Taxol and collagenase is effective for visualizing microtubules in epithelial cells, and that microtubules may play important roles in both positioning of the Golgi apparatus and transport of secretory granules. Our results also support the idea that the Golgi apparatus may act as an organizing center for microtubules.     

Clathrin sheets on the protoplasmic surface of ventral membranes of osteoclasts in culture

Physical cell-shearing resulted in various degrees of disruption of the basolateral (upper) membranes, cytoskeletons or cell organelles and exposed the protoplasmic surface of ventral (adhesion) membranes of osteoclasts that were attached to the underlying substratum, such as coverslips, mica or synthetic apatite plates. Freeze-dried replicas of the ventral membranes left behind on the substratum after cell-shearing provided three-dimensional information on the ultrastructure of the protoplasmic membrane surface of cultured osteoclasts. An extensive area of the protoplasmic surface and various amounts of cytoskeletal structures attached to the adherent ventral surface of the plasma membrane were visible. In particular, the most characteristic finding of the present study is that numerous clathrin sheets displaying various sizes, shapes and curvature were revealed on the ventral membrane. The polygon substructures of the clathrin lattices appeared to be composed of hexagons with a few pentagons interspersed. They were seen at the peripheral membranes where they were situated at the sites of close contact with the underlying substratum. In addition, clathrin lattices were never observed on the basolateral (upper) membranes. In favourable stereo views, most cytoskeletons were not in direct contact with the clathrin sheets. However, a few observations indicated possible remnants of cytoskeletons attached to clathrin lattices. Podosomes did not have a direct structural relationship to clathrin lattices. Although it is generally accepted that cytoskeletal podosomes in motile cells, such as osteoclasts, play a major role in cell adhesion, the present study indicates that membrane-associated clathrin might also function during attachment to the substrate. In this regard, clathrin is thought to be required for receptor-mediated endocytosis, but whether it might also function in cell attachment is still a matter for debate. This type of clathrin-related adhesion appears to be a previously unrecognized site of cell/substrate adhesion in osteoclasts. To assess this possible function, we focused on clathrin and related cytoskeletal elements on the ventral membranes of cultured osteoclasts.     

Thiamine diphosphate absorption by the cells of Pliss lymphosarcoma and Ehrlich ascitic cancer

Concentration difference of vitamin B1 coenzyme in blood and in ascitic fluid was found in mice with the Ehrlich ascites tumour. The thiamine diphosphate deficiency was detected in the liver of rats with the Pliss lymphosarcoma. The introduction of cocarboxylase to animals was accompanied by the active absorption of this coenzyme by tumours. It is observed that experimental tumours disturb the vitamin B1 balance in the organism.     

Three-dimensional seismic endoscopy. I. Design of apparatus andbasic imaging algorithms

A method, called "seismic endoscopy," able to perform three-dimensional (3-D) acoustical imaging in a cylindrical volume around shallow-depth boreholes is described. The main characteristics of borehole tools designed and constructed in the authors' laboratory are presented. Several tests performed in an acoustical water tank are used to illustrate the basic imaging algorithms adapted to the particular acquisition geometry of the probes. In particular, both the filtering of borehole waves and azimuthal refocusing are discussed     

NGN网络测试仪H.248解码模块的设计与实现

NGN网络通过引入软交换技术实现了对于业务的控制和承载的分离,使网络融合成为可能;实际网络中普遍采用的H.248协议作为实现软交换的核心协议,因此要实现软交换并监测NGN核心网的运行情况,对H.248协议的解码就成为了要完成的最基本功能。本文介绍了H.248协议的基本概念及其在NGN网络中的作用接口,分析了它的协议连接模型和消息结构,并根据它的文本编码方式和二进制编码方式分别提出了解码的算法思想,设计了解码流程;最后通过对实际数据的分析,验证了设计实现的有效性和可靠性。     

高尔基氏体的显微与亚显微结构

本文采用光镜和电镜技术对高尔基氏体的显微与亚显微结构进行观察和研究。取人体胃癌组织,经常规TEM标本制片后,在电镜下观察胃癌细胞中的高尔基氏体。应用我们制备的单克隆抗体,染色显示人乳腺癌、大肠癌细胞和非洲绿猴肾上皮细胞(CV-1)等的高尔基氏体。以超速离心获取的培养大     

Simultaneous measurement of electrical activity from two colonicsmooth muscle layers using a dual sucrose gap apparatus

An apparatus using the sucrose gap technique is presented. With this apparatus simultaneous measurements of contractile and intracellular electrical activity from the two smooth muscle layers of the colon are made. An "L-shaped" muscle preparation consisting of a leg from the circular muscle layer and a leg from the longitudinal muscle layer is used. A theoretical discussion of the device's operation is presented. Finally, experimental results that validate the theory are included.     

Nucleolar apparatus function and the ribosomal gene activity of mouse embryonic fibroblasts infected by the SA7(C8) virus

Computer morphometry revealed statistically significant (P less than 0.001) decrease in the number and area of nucleoli and ribosomal gene activities (as demonstrated by AgNOR staining) in primary mouse embryonal fibroblast cultures infected by oncogenic adenovirus SA7(C8). Even more drastic increased in these parameters was found when serum-depleted cultures were infected. There were no effects on nucleolar and AgNOR parameters in mock-infected cultures. It is suggested that an increase in the ribosomal gene activity may reflect synthesis of SA7(C8) early gene products in target cells.     

A study of the apparatus function of a grid Fabry-Perot interferometer used as a F.I.R. spectrometer: Computing of the spectrum

Influences of various parameters on the apparatus function of a F.I.R. grid Fabry-Perot spectrometer are analysed. A pseudo-deconvolution method allowing an improvement of experimental results is tested by simulation and then applied to data concerning the isotopic HCl doublet at 41 cm^?1.     

中频理疗仪的控制系统

摘要本文介绍了中频理疗仪的工作原理，控制系统的技术指标、控制原理和解决的关键技术问题。该系统具有性能稳定可靠，结构简单，操作方便。且价格低廉，易实现产品化等优点。     

射频功率校准仪的GPIB接口开发

为了满足组建以PC为中心的射频功率自动校准系统的需求,提高射频功率校准及射频功率检测的效率。本文利用NAT9914GPIB接口专用芯片设计了一种以ARM为核心的射频功率校准仪的GPIB接口电路．并详细讨论了GPIB接口功能的软件实现方法,并给出了软件设计的流程图。基于此种方法设计的GPIB接口卡已成功应用于射频功率自动校准系统中,取得了良好的效果,实现了GPIB的基本功能。对相关工程技术人员有一定的借鉴作用。     

The discovery of the division apparatus of plastids and mitochondria

Mitochondria and plastids contain distinct genomes and multiply by binary division of existing organelles. Mitochondrial and plastid division can be clearly separated into two main events: division of the organelle nuclei (nucleoids), and subsequent division of the rest of the organelles, the process of organellokinesis. Organellokinesis makes use of organelle dividing apparatuses such as plastid-dividing ring (PD ring) and mitochondrion-dividing ring (MD ring). The plastid-dividing apparatus (PD apparatus) is composed of three electron-dense rings (the outer, middle and inner), while the mitochondrion-dividing apparatus (MD apparatus) is a pair of electron-dense rings in cytoplasm and inner ring in the mitochondrial matrix. The behaviour of both the PD and MD apparatuses throughout organelle division in Cyanidioschyzon merolae has been studied in detail by electron microscopy. When cells enter mitosis, the inner PD ring forms first, followed by the outer and middle rings and finally the MD rings. The PD rings begin to contract before the MD rings. However, the MD rings start to contract at about 4 times the speed of the PD rings and catch up to the PD rings. The cross-sectional areas of both the outer PD and MD rings increase as contraction in the plane of division progress. This suggests that the outer rings of organelle dividing apparatuses (OD apparatus) provide the motive force for contraction. FtsZ protein is located on the bacterial contractile ring at the equator of dividing bacteria, and controls bacterial division. Since FtsZ contains a tubulin motif, and host eukaryotic organisms and chloroplasts evolved from bacteria, there is debate whether that tubulins found in the cytoskeleton and the inner or outer PD ring evolved from FtsZ protein during eukaryogenesis.     

过采样技术在扭矩扳子检定仪中的研究

过采样技术能够有效减小模数转换过程的噪声功率,从而提高模数转换器的分辨率。基于奈奎斯特采样定理,对模数转换器的采样频率和量化误差进行分析。通过理论分析得出,每增加一位分辨率需要增加4倍采样频率,并提出了3个影响过采样技术有效性的因素。通过在扭矩扳子检定仪中的应用过采样技术,使扭矩扳子检定仪的模数转换器提高了4位分辨率。在此基础上,对过采样技术进行了改进,使扭矩扳子检定仪的精度提高到0.3%以上。     

小型加速度测试仪在转管武器中的应用

针对转管武器发射时的特殊环境,采用存储测试技术,研制了小型加速度测试仪。文中介绍了研制小型加速度测试仪的背景和意义,阐述了测试仪的工作原理及关键技术,分析了所用加速度传感器灵敏度校准的实现过程,并给出了系统抗冲击的处理方法。该测试仪体积小、功耗低,可用电池供电,能够实时记录被测枪弹在枪管中的相关运动信息,并能在系统掉电情况下保持所测数据,为高射速武器的研制提供了重要参考手段。