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61.
Recombinant human granulocyte colony-stimulating factor (G-CSF) at a dose of 1 to 300 micrograms/kg/day was administered intravenously to rats daily for 13 weeks. Serum alkaline phosphatase (ALP) activity increased dose-dependently with leukocytosis. Most of the increased leukocytes were segmented neutrophils, and neutrophil alkaline phosphatase (NAP) scores were elevated markedly. Serum ALP activity correlated very well with the segmented neutrophil counts, and the coefficient of correlation was more than 0.97 in both sexes. Pathological examinations revealed splenomegaly and a marked increase in neutrophils in the red pulp of the spleen. In the spleen, phagocytosis of neutrophils by macrophages was observed. These data indicate that the increased ALP was of neutrophil origin. Serum ALP activity may be increased by the direct release of ALP from the high number of neutrophils into the blood, or by the leakage of ALP into the blood mainly from the spleen where many neutrophils are pooled and destroyed by the macrophage system. 相似文献
62.
Andreja Erman Urka Kamenek Urka Dragin Jerman Mojca Pavlin Maja emaar Peter Verani
Rok Romih 《International journal of molecular sciences》2021,22(12)
Non-muscle-invasive bladder cancer is the most common form of bladder cancer. The main problem in managing bladder tumors is the high recurrence after the transurethral resection of bladder tumors (TURBT). Our study aimed to examine the fate of intravesically applied cancer cells as the implantation of cancer cells after TURBT is thought to be a cause of tumor recurrence. We established an orthotopic mouse bladder tumor model with MB49-GFP cancer cells and traced them during the first three days to define their location and contacts with normal urothelial cells. Data were obtained by Western blot, immunolabeling, and light and electron microscopy. We showed that within the first two hours, applied cancer cells adhered to the traumatized epithelium by cell projections containing α3β1 integrin on their tips. Cancer cells then migrated through the epithelium and on day 3, they reached the basal lamina or even penetrated it. In established bladder tumors, E-cadherin and desmoplakin 1/2 were shown as feasible immunohistochemical markers of tumor margins based on the immunolabeling of various junctional proteins. Altogether, these results for the first time illustrate cancer cell implantation in vivo mimicking cellular events of tumor recurrence in bladder cancer patients. 相似文献
63.
Many processing techniques, such as hot dip aluminizing, bimetal formation, liquid metal corrosion, cementing, welding and diffusion bonding, are basically dependent on interfacial reactions [1-3]. It is therefore important to investigate the formation and growth of intermetallic layers at the interface. There have been several studies carried out to examine chemical compositions and growth kinetics of intermetallic layers in the Al-Fe system [4-9]. Most authors have come to an agreement that… 相似文献
64.
Electrospinning of polyurethane fibers 总被引:5,自引:0,他引:5
A segmented polyurethaneurea based on poly(tetramethylene oxide)glycol, a cycloaliphatic diisocyanate and an unsymmetrical diamine were prepared. Urea content of the copolymer was 35 wt%. Electrospinning behavior of this elastomeric polyurethaneurea copolymer in solution was studied. The effects of electrical field, temperature, conductivity and viscosity of the solution on the electrospinning process and morphology and property of the fibers obtained were investigated. Results of observations made by optical microscope, atomic force microscope and scanning electron microscope were interpreted and compared with literature data available on the electrospinning behavior of other polymeric systems. 相似文献
65.
针对目前海洋混凝土工程的腐蚀现状,进行了海洋微生物对潮差区混凝土的作用机理及完善海工混凝土的腐蚀机理探索.通过海工混凝土潮差区部位取样,对暴露于潮差区中部22 y的混凝土试样表面进行FE-SEM、EDAX分析,结果表明:潮差区混凝土表面腐蚀严重,结构疏松,表面覆盖有有机物质和微生物.并将暴露于潮差区中部22 y的混凝土试样和该取样位置挂置7 d的混凝土试样表面的微生物群落分别分离,克隆了其中30株和12株细菌的16S rDNA基因,测定其序列且进行比对,其分别属于15个和7个种属中.优势种属均为假交替单胞菌,但随着暴露时间的增加,总细菌株数和总菌属数分别增大到2.5和2.14倍,且种属的变化也很大.同时,建立了海洋混凝土工程表面细菌鉴定方法,以及分离、鉴定的菌种为后续细菌对混凝土作用的试验提供菌种. 相似文献
66.
为了研究钢纤维混凝土(SFRC)常温以及经历400和800℃高温后的动态压缩性能,采用改进的分离式Hopkinson压杆装置,结合应变直测技术对其进行了单轴冲击压缩试验.结果表明:经历400和800℃高温后,未掺钢纤维混凝土的峰值应力分别只有常温时的79.2%和38.9%,弹性模量分别降为常温时的82.8%和56.2%,同时,试件的能量吸收能力大幅度下降;钢纤维混凝土400,800℃对应的峰值应力分别降为常温时的76.8%和39.0%,弹性模量稍有降低,分别为常温的91.8%和82.7%,较基准混凝土有了较大的提高.钢纤维的加入可以增加混凝土的极限应力对应应变,曲线的下降段较为平缓,同时增强了混凝土的能量吸收能力,在20,400和800℃时,分别提高了38.5%,27.5%和25%. 相似文献
67.
为了研究电化学除氯对混凝土中离子分布和微观结构的影响规律,采用压汞法、SEM电子显微镜分析等方法对电化学除氯后不同水灰比混凝土试件中钢筋附近和表面层的氯离子和钾钠离子含量、孔隙结构、显微结构进行对比分析.结果显示,电化学除氯后,钢筋附近混凝土与外层混凝土相比,氯离子含量约为1/2,钾离子含量约为5~10倍,钠离子含量约为8~18倍,水化物颗粒间结合不连续、部分水化产物分解.钢筋附近区域混凝土中的氯离子含量明显低于外表层混凝土,钾、钠离子在钢筋阴极附近大量聚集.经过电化学处理后的混凝土试件钢筋附近区域的孔隙率和大孔含量增多,结构疏松;而外表层混凝土结构致密,孔隙细化,水化产物成网络状结合良好. 相似文献
68.
69.
In the indoor visible light transmission environment with complex noise, traditional received signal strength indication(RSSI)localization algorithm and imaging localization algorithm are unable to accurately determine the reason of the inaccurate localization model and inadequate constraints of position coordinates. In order to solve the problems, a visible light localization algorithm based on multi-measurements constraints is presented in the paper. The algorithm first constructs a joint localization state space model based on RSSI localization and the imaging localization algorithm. Then, states, measurements and their equations are constructed based on the space model. Finally, the equations are resolved using the unscented Kalman filter(UKF). Compared with RSSI localization and imaging localization, simulation results show that the RMSE of the proposed algorithm could be closer to the Cramer Rao bound. Besides, the localization probability of the proposed algorithm is higher than that of RSSI localization and imaging localization algorithm. 相似文献
70.
Surface reconstruction for incremental forming 总被引:1,自引:0,他引:1
A. Erman Tekkaya Ravi Shankar Gerd Sebastiani Werner Homberg Matthias Kleiner 《Production Engineering》2007,1(1):71-78
In spite of extensive efforts being made with regard to virtual process optimization technology, the production of prototype
parts is still a necessity. With respect to the production of sheet metal parts in low quantities, incremental sheet metal
forming (ISMF) is a highly interesting process. ISMF allows the production of complex parts with drastically reduced costs
in tooling and machinery compared to conventional processes like deep drawing. However, ISMF, with it’s incremental nature,
introduces the need for generating a tool path considering both final geometry and process-induced deviations or constraints.
Consequently, for the generation of the tool path a (tool path) surface, with an adequate offset, is necessary. That is why,
within the scope of extensive research work at the Institute of Forming Technology and Lightweight Construction (IUL), a special
correction module has been developed, determining this offset e.g. depending on the workpiece geometry. This paper presents
the algorithm, the application, and the effect on the produced parts. Furthermore, a concept for an extension regarding further
constraints like elastic workpiece behavior is presented. 相似文献