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921.
922.
序列解剖层片的全局和局部色彩校正 总被引:1,自引:0,他引:1
本研究提出了一种全局和局部相结合的序列解剖层片的色彩校正算法。利用数字人层片(中国女婴一号)上提供的彩色灰度卡对相邻层片间各颜色通道的色彩差异进行全局校正,以消除解剖数据集沿垂直方向的光照变化;再利用线性校正模型和差值图像各通道(R、G、B)的灰度局部直方图,对解剖数据集进行局部色彩差异校正。重建结果表明,经过全局和局部色彩校正后,重建视图中的明暗条纹基本消失,说明层片间颜色的不连续现象得到了校正。 相似文献
923.
V. A. Struchkov N. B. Strazhevskaya D. Yu. Blokhin 《Bulletin of experimental biology and medicine》1992,113(5):716-719
All-Russian Oncologic Scientific Center, Academy of Medical Sciences, Moscow. (Presented by Academician of the Academy of Medical Sciences N. N. Trapeznikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 113, No. 5, pp. 529–531, May, 1992. 相似文献
924.
Hyaluronan-dependent pericellular matrices or "coats" are expressed by a variety of cell types in culture and modulation of their expression may be important in regulation of cell interactions in vivo during development. Monoclonal antibody IVd4, which recognizes hyaluronan-binding protein with the properties of a hyaluronan receptor, was shown to block formation of these coats by a variety of cells. Using rat fibrosarcoma cells, it was found that the antibody not only blocked initial formation of the coats but also caused their loss when added subsequent to formation. The loss of preformed coats in the presence of antibody occurred at 4 degrees and 37 degrees, implying that the function of hyaluronan-binding protein in coat formation is not in mediating metabolic processes. The antibody also had no significant effect on hyaluronan production by the fibrosarcoma cells. In addition, hyaluronan hexasaccharide, a competitive inhibitor of the interaction between polymeric hyaluronan and its cell surface receptor, was found to inhibit coat formation. Thus it is concluded that a hyaluronan-binding protein with the properties of a hyaluronan receptor is required for pericellular matrix formation. 相似文献
925.
Fa-Ten Kao Suhong Tong Yiping Shen Jingwei Yu 《Somatic Cell and Molecular Genetics》1996,22(3):191-199
Three region-specific libraries for the entire human chromosome 18 were constructed using microdissection and MboI linker-adaptor
microcloning techniques. The libraries included 18pter-p11.1 (designated 18P library), 18q 11.1-q12.3 (18Q1 library), and
18q21.1-qter (18Q2 library). Samples of the microclones from each library were analyzed in detail. The insert sizes ranged
between 50–600 bp, with a mean of 180–220 bp for the three libraries. The libraries contained approximately 40–60% microclones
with unique sequence inserts. More than 30 unique sequence microclones from each library were analyzed by Southern blot hybridization
to demonstrate that they are human specific and were derived from chromosome 18. The human gemomic HindIII fragments hybridized
to each microclone were determined and microclones crosshybridized to rodent species were identified. These region-specific
libraries and the unique sequence microclones from the libraries are useful reagents for (1) isolating hughly polymorphic
microsatellite markers for refined linkage analysis, (2) identifying corresponding YAC, BAC or other clones with large inserts
for contig assembly and high resolution physical mapping, (3) isolating cDNA clones from the dissected region, and (4) convenient
sequencing of the microclones to prepare high density markers and sequence-tagged sites (STSs). Such applications have been
demonstrated in a series of similarly constructed microdissection libraries from other regions of the human genome. 相似文献
926.
Ho Chang Kuo Chih Lu Wang Chi Di Liang Hong Ren Yu Hsin Hsu Chen Lin Wang Kuender D Yang 《Journal of microbiology, immunology, and infection》2007,40(5):395-400
BACKGROUND AND PURPOSE: This study was conducted to investigate whether changes in the complete blood count (CBC)/differential count (DC) and C-reactive protein (CRP) were correlated to Kawasaki disease (KD) with coronary artery lesions (CALs). METHODS: A retrospective analysis was performed of all children with KD at Chang Gung Memorial Hospital at Kaohsiung from 2001 to 2006. KD patients were divided into those with and without CALs for testing of correlations with changes in CBC/DC and CRP levels. RESULTS: A total of 147 patients were enrolled for this analysis. Serial CBC/DC and CRP measurements and echocardiographic data for determination of CAL formation were obtained before and after intravenous immunoglobulin (IVIG) treatment. There were 44 (29%) KD patients having CAL formation (>3 mm in diameter of internal lumen). There was no significant difference in terms of age distribution and major diagnostic criteria between KD patients with and without CALs. Male KD patients, however, had a significantly higher rate of CAL formation (p=0.009). In multivariate logistical regression analysis, persistent monocytosis after IVIG treatment was the only factor significantly correlated to CAL formation (p=0.003). CONCLUSIONS: Of the febrile routine measurements of CBC/DC and CRP in KD, persistent monocytosis after IVIG treatment was correlated to CAL formation. Further studies to clarify the mechanism of monocytosis may help prevent the CALs of KD. 相似文献
927.
复杂手术常需多科医生协商制定综合性治疗方案,网络协同三维可视化软件可使方案制定直观而精确。我们采用VTK工具包对DICOM格式CT图像数据进行三维重建并作网格简化,将结果所得多边形网格模型无缝集成到用HOOPS/3DAF所开发的图形系统进行显示,并用HOOPS/Stream工具包转成适合网络传输的HSF无损压缩流文件,再用HOOPS/NET工具包实现基于Client/Server架构的协同三维交互可视化系统。所得三维重建结果清晰,协同三维可视化操作实时度高。本研究实现了一个协同手术仿真开发平台,该架构易于进一步添加模拟手术操作与修复体设计功能。 相似文献
928.
A. L. Dranov A. S. Dudnichenko I. A. Mezin R. F. Menzeleev Yu. M. Krasnopol'skii V. I. Shvets 《Bulletin of experimental biology and medicine》1996,121(1):77-80
Study of the toxicity and pharmacokinetics of free and liposomal forms of cytostatics revealed an appreciable decrease of
the toxicity of high drug doses and prolongation of drug action in liposomes. The distribution of drugs in organs and tissues
is shown.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N
o
1, pp. 85–88, January, 1996 相似文献
929.
N. N. Dygalo G. T. Shishkina N. Yu. Surnina A. A. Yushkova 《Bulletin of experimental biology and medicine》1995,119(3):320-322
Tissue specificity of the effect of glucocorticoids on the density of β-adrenoreceptors is shown. The hormone increases the
number of receptors in the lungs, but has no effect on their density in the cerebral cortex either in the norm or after down-regulation.
Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N
o
3, pp. 328–330, March, 1995
Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences 相似文献
930.
In a previous study we demonstrated thirteen amino acids to be essential and two to be partially essential for lymphocyte proliferation. Arginine is one of the essential amino acids, and the highly purified arginase strongly inhibited lymphocyte proliferation. The modulation of lymphocyte growth by various amino acid-degrading enzymes was studied. Peripheral lymphocytes were cultured in RPMI 1640 with or without amino acid-degrading enzyme for 72 h. A total of 17 commercial L-amino acid-degrading enzymes were studied. At 10 micrograms/ml, both lysine decarboxylase and asparaginase completely inhibited lymphocyte proliferation, arginase resulted in 78% inhibition and tyrosinase 57% inhibition. Other enzymes inhibited less than 20% lymphocyte proliferation; they included alanine dehydrogenase, arginine decarboxylase, aspartase, glutamic decarboxylase, glutamic dehydrogenase, glutaminase, histidase, histidine decarboxylase, leucine dehydrogenase, phenylalanine decarboxylase, phenylalanine hydroxylase, tryptophanase, and tyrosine decarboxylase. All four enzymes that strongly inhibited lymphocyte proliferation degraded amino acids that are essential for lymphocyte growth. 相似文献