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991.
V. G. Bashkatova G. Yu. Vitskova V. B. Narkevich V. D. Mikoyan A. F. Vanin K. S. Raevskii 《Bulletin of experimental biology and medicine》1998,125(1):20-22
The content of nitric oxide in convulsions of different genesis is assessed by measuring the formation of paramagnetic mononitrosyl
iron complexes with diethylthiocarbamate by electron paramagnetic resonance. A 3- to 4-fold increase in the content of these
complexes is found in the brain of rats with thiosemicarbazide- or N-methyl-DL-aspartate-induced seizures in comparison with
control animals. A similar increase in the brain NO content was observed in maximum electrical stimulation of metrazol-induced
convulsions. These changes were accompanied by elevation of secondary lipid peroxidation products.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 125, No. 1, pp. 26–29, January, 1998 相似文献
992.
根据Wiederhielm的阻抗平衡压力检测原理,设计了一个改进的伺服零微血管测压系统。利用该系统检测了蟾蜍及蛙肠系膜内微小动脉的压力、获得了各管径级的压力和脉压的参数,并观察了药物的作用,探讨了微动脉内压力的波动特性以及应激情况下压力的骤变式与脉动式的交替,为微循环研究提供一些有价值的现象。 相似文献
993.
白细胞介素3基因疗法和白细胞介素6基因疗法的联合造血调控作用 总被引:2,自引:0,他引:2
研究了成纤维细胞介导的IL-3基因疗法,IL-6基因疗法以两者联合后对造血系统的影响。结果发现,单用IL-基因疗法的小鼠白细胞总数,中性粒细胞,骨髓CFU-GM,CFU-MK等显著上升,但血小板上升程度经,单用IL-6基因疗法的小鼠血小板,中性粒细胞,骨髓CFU-GM,CFU-MK上晚为显著。 相似文献
994.
The problem of generating delivery options for one-dimensional intensity-modulated beams (1D IMBs) arises in intensity-modulated radiation therapy. In this paper, we present an algorithm with the optimal running time, based on the 'rightmost-preference' method, for generating all distinct delivery options for an arbitrary 1D IMB. The previously best known method for generating delivery options for a 1D IMB with N left leaf positions and N right leaf positions is a 'brute-force' solution, which first generates all N! possible combinations of the left and right leaf positions and then removes combinations that are not physically allowed delivery options. Compared with the brute-force method, our algorithm has several advantages: (1) our algorithm runs in an optimal time that is linearly proportional to the total number of distinct delivery options that it actually produces. Note that for a 1D IMB with multiple peaks, the total number of distinct delivery options in general tends to be considerably smaller than the worst case N!. (2) Our algorithm can be adapted to generating delivery options subject to additional constraints such as the 'minimum leaf separation' constraint. (3) Our algorithm can also be used to generate random subsets of delivery options; this feature is especially useful when the 1D IMBs in question have too many delivery options for a computer to store and process. The key idea of our method is that we impose an order on how left leaf positions should be paired with right leaf positions. Experiments indicated that our rightmost-preference algorithm runs dramatically faster than the brute-force algorithm. This implies that our algorithm can handle 1D IMBs whose sizes are substantially larger than those handled by the brute-force method. Applications of our algorithm in therapeutic techniques such as intensity-modulated arc therapy and 2D modulations are also discussed. 相似文献
995.
为了探讨一种适合培养细胞的低本底、低成本免疫细胞化学方法 ,本研究将低浓度的 Triton X-10 0加入抗体稀释液和洗液中 ,观察了其对 ABC反应时的抗体和 ABC的使用浓度和反应效果的影响。结果证明 ,在抗体稀释液和洗液中加入 0 .1%Triton X-10 0可以增强细胞对抗体的通透性 ,在不减弱阳性信号的状况下使 -抗的使用浓度明显降低 ,使生物素化二抗和 ABC的使用浓度达到 1/ 10 0 0~ 1/ 40 0 0 ,并大大减弱染色本底。本研究结果提示 ,在这一稀释度明显低于目前试剂盒建议的使用浓度。在充分显示阳性信号的前提下 ,使抗体的使用浓度和量大幅度减少 ,从而实现了降低本底和实验成本的目的 相似文献
996.
997.
O. V. Antonova D. A. Gryadunov S. A. Lapa A. V. Kuz’min E. E. Larionova T. G. Smirnova E. Yu. Nosova O. I. Skotnikova L. N. Chernousova A. M. Moroz A. S. Zasedatelev V. M. Mikhailovich 《Bulletin of experimental biology and medicine》2008,145(1):108-113
We developed a method of identification of Mycobacterium tuberculosis with simultaneous evaluation of the sensitivity to fluoroquinolones on a biological microchip array. The method of multiplex
two-staged PCR followed by hybridization of a biochip makes it possible to detect 8 mutant variants of gyrA gene occurring in fluoroquinolone-resistant strains (∼85% all resistant forms) within 1 day. Using this method we analyzed
107 cultures isolated from patients with tuberculosis and 78 sputum samples. Mutations in gyrA gene were detected in 48 (92%) resistant strains. Natural S95T polymorphism in gyrA gene was detected in all resistant and in 76% sensitive strains. The sensitivity and specificity of the proposed method calculated
on the basis of the analysis of sputum samples (n=78) were 94 and 100%, respectively.
__________
Translated from Byulleten’ Eksperimental’noi Biologii i Meditsiny, Vol. 145, No. 1, pp. 115–120, January, 2008 相似文献
998.
Yu. V. Pakin 《Bulletin of experimental biology and medicine》1977,83(4):555-557
The effect of the cultivation temperature on blast transformation of lymphocytes from persons aged 20–35 and 90–102 years induced by phytohemagglutinin was studied. Cultivation at 39°C was found to increase, but at 41°C to reduce sharply the index of blast transformation compared with the control (37°C). The effect of cultivation temperature on the blast-transformation process has certain features which depend on the donors' age.Institute of Gerontology, Academy of Medical Sciences of the USSR, Kiev. (Presented by Academician of the Academy of Medical Sciences of the USSR D. F. Chebotarev.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 470–472, April, 1977. 相似文献
999.
Adenovirus-mediated intratumoral lymphotactin gene transfer potentiates the antibody-targeted superantigen therapy of cancer 总被引:6,自引:0,他引:6
Wang Q Yu H Zhang L Ju D Pan J Xia D Yao H Zhang W Wang J Cao X 《Journal of molecular medicine (Berlin, Germany)》2002,80(9):585-594
Bacterial superantigens are extremely potent activators of murine and human T lymphocytes. To engineer superantigens for cancer immunotherapy, staphylococcal enterotoxin A (SEA) was genetically fused to the Fab region of the human colon carcinoma-reactive monoclonal antibody (mAb) C215. Fusion protein C215Fab-SEA can trigger cytotoxic T cells against C215 antigen positive tumor cells and induce tumor-suppressive cytokines. However, the antitumor effect of C215Fab-SEA is often not satisfactory because of T cell deletion after activation and failure to induce potent CTL activity after repeated administration. Lymphotactin (Lptn) is a potent chemoattractant for T cells and NK cells. To improve the therapeutic efficacy of fusion protein C215Fab-SEA we investigated in this study the antitumor responses elicited by combination of C215Fab-SEA and adenovirus-mediated intratumoral Lptn gene transfer in the preestablished C215 antigen expressing B16 melanoma murine model. More significant inhibition of tumor growth and prolonged survival time were observed in tumor-bearing mice that received combined therapy of C215Fab-SEA and Ad-Lptn than those of mice treated with C215Fab-SEA or Ad-Lptn alone. The highest CTL activity of tumor-bearing mice was induced after combined therapy. Intratumoral coadministration of C215Fab-SEA and Ad-Lptn augmented splenic NK activity of tumor-bearing mice most markedly. Our data demonstrate that the in vivo antitumor effect of C215Fab-SEA immunotherapy is potentiated significantly by combination with intratumoral Lptn gene transfer through more efficient induction of specific and nonspecific antitumor immune responses. 相似文献
1000.
比较Ⅰ型胶原与胞外基质(extracellularmatrix,EM)提取物冻干后形成的膜(EM膜)在体外构建人工真皮的能力,以选择一种更有利于人工真皮形成的支架材料。方法分别使用小牛真皮部分提取的Ⅰ型胶原蛋白和胞外基质提取物冻干后制备基质网架,植入皮肤成纤维细胞,形成人工真皮。用扫描电镜观察I型胶原膜和EM膜的表面形态结构;选取不同的时间点,对种植于两种支架材料上的细胞进行计数,并利用间接ELISA方法检测人工真皮复合物中的细胞Ⅰ型胶原分泌情况,通过统计学的分析手段,对细胞的生长情况做出判断;用组织学方法观察人工真皮的形成情况。结果扫描电镜观察结果,两种膜在外观形态上无明显差异;细胞在EM膜上的增殖速度较Ⅰ型胶原膜快;ELISA分析显示,EM-细胞复合物中的成纤维细胞能够分泌更多的Ⅰ型胶原;与Ⅰ型胶原膜相比,EM在培养液中的降解更为缓慢,种植后的成纤维细胞在EM膜上生长旺盛,细胞层次明显多于前者,形成了较为明显的真皮样组织。结论EM膜适于成纤维细胞的生长,体外降解速率慢,是一种较Ⅰ型胶原膜更为理想的真皮支架材料。 相似文献