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891.
The plasminogen activator system has been found to modulate neoplastic spread and angiogenesis in tumors. An angiogenesis inhibitor, TNP-470, has been shown to possess potent antitumor activities in various types of cancer cells. We therefore investigated the inhibitory effect of TNP-470 on cancer cell proliferation, and the suppressive effect of TNP-470 on urokinase-type plasminogen activator (u-PA) and its inhibitor (PAI-1), in human lung cancer cell lines in vitro. TNP-470 inhibited cell proliferation in a dose-dependent manner in both cell lines. u-PA and PAI-1 in culture supernatants were suppressed with the concentrations of TNP-470, in association with a decrease in viable cancer cells. Unchanged serum levels of u-PA and PAI-1 would be of great advantage to the diseased patients, since the plasminogen activator system has a crucial function in the process of distant metastasis.  相似文献   
892.
Two novel triterpene glycosides, achyranthosides E and F, were isolated as methyl esters from the root of Achyranthes fauriei, an antiinflammatory medicinal plant. Their structures were characterized as oleanolic acid glucuronides having unique substituents composed of C6H9O5 and C9H15O7, respectively, at the C-3 position of glucuronic acid. These compounds are active components which can inhibit the excess recruiting of neutrophiles to injured tissues 1,000 times more potently than sialyl Lewis X.  相似文献   
893.
99Tcm-glucarate accumulation in human mammary BT-20 tumours hosted in severe combined immune deficiency (SCID) mice was compared to 111In-monoclonal antibody 103D2-F(ab')2, 99Tcm-methoxyisobutyl isonitrile (99Tcm-MIBI) and 99Tcm-diethylenetriamine pentaacetate (99Tcm-DTPA). The intracellular tumour distribution of 99Tcm-glucarate was also determined. SCID mice injected with a mixture of 99Tcm-glucarate and 111In-103D2-F(ab')2 were imaged serially up until 24 h. Computer planimetered tumour-to-blood activity (in the heart) ratios (T/BH) to 8 h were significantly greater for 99Tcm-glucarate than 111In-103D2. The mean (+/-S.D.) tumour-to-blood ratio (T/B) from biodistribution was 1.21 +/- 0.31 and 0.35 +/- 0.06 (P < 0.0001) at 5 h, and 1.526 +/- 0.29 and 0.75 +/- 0.2 (P < 0.0001) at 8 h, for 99Tcm-glucarate and 111In-103D2 respectively. At 24 h, T/B for 111In-103D2 (1.76 +/- 0.22) exceeded that of 99Tcm-glucarate (1.44 +/- 0.2, P = 0.01). 99Tcm-glucarate uptake in the tumours at 5 h (1.133 +/- 0.25 %ID g-1) and 8 h (1.213 +/- 0.23 %ID g-1) was significantly greater than that of 99Tcm-MIBI (0.340 +/- 0.09, P = 0.0002; 0.220 +/- 0.04, P = 0.0001) and 99Tcm-DTPA (0.091 +/- 0.03, P < 0.0002; 0.016 +/- 0.01, P < 0.0001) respectively. Intracellular tumour distribution of 99Tcm-glucarate was 50.91 +/- 6.55% in the nuclear fraction, 34.34 +/- 2.88% in the cytoplasmic fraction and 14.75 +/- 7.66% in the mitochondrial fraction. Thus glucarate may provide a 99Tcm-based mammary tumour imaging modality for visualization of tumours very quickly after tracer administration with maximal targeting in the nuclei of the tumour cells.  相似文献   
894.
895.
PURPOSE: To provide methods for stereoscopic visual demonstration from 3D reconstructed MR angiographic images. METHODS: Stereoscopic viewing can be obtained with pairs of images that are displayed at angles of 15 degrees. Optical devices as stereoscopic binoculars or minor stereoscopes facilitate stereoscopic viewing. The possibility of stereoscopic projections for a larger auditorium is mentioned. RESULTS: Using three clinical examples the advantages of stereoscopic display of MR angiograms are demonstrated. CONCLUSIONS: MR angiography allows stereoscopic viewing with simple methods, like CT- and conventional rotation angiography. This principle, which has been known for 100 years, may thus acquire a new significance.  相似文献   
896.
The function of proliferation-associated nucleolar protein p120 is unclear. A recent report that a yeast protein, NOP2, 67% homologous to human p120, is up-regulated during the onset of growth and influences the morphology of the nucleolus supports the notion that this protein could serve as a marker for proliferation in neoplastic cells. Lung cancer is characteristic in that different histological types show different biological features. We attempted to evaluate the levels of p120 expression in resected human lung cancer tissues of different histological types and the relation of p120 expression and cell proliferation using human lung cancer cell lines. When 37 frozen specimens of human lung cancer and normal lung were stained with a p120 monoclonal antibody, the nucleoli of cancer cells were positively stained, whereas a few macrophages in normal lung revealed only weak staining. The labeling index of p120 in squamous cell carcinoma (67.7 +/- 12.4%) was significantly higher than that in adenocarcinoma (35.3 +/- 12.6%) or in large cell carcinoma (30.1 +/- 17.3%; P < 0.01). In six human lung cancer cell lines and one normal lung fibroblast cell line cultured in vitro, there was a significant correlation between S-phase fraction and p120 mRNA (r = 0.851, P < 0.02)/p120 protein (r = 0.869, P < 0.01) or between doubling time and p120 protein (r = -0.928, P < 0.01). In the context of the reports that indicate higher [3H]thymidine incorporation and shorter doubling time in the squamous cell carcinoma, these results indicate that p120 can be a marker for proliferation in human lung cancer cells in vivo and in vitro, and that it has an important function in the cell cycle of tumor proliferation.  相似文献   
897.
A novel actin filament (F-actin)-binding protein with a molecular mass of approximately 205 kD (p205), which was concentrated at cadherin-based cell-to-cell adherens junction (AJ), was isolated and characterized. p205 was purified from rat brain and its cDNA was cloned from a rat brain cDNA library. p205 was a protein of 1,829 amino acids (aa) with a calculated molecular mass of 207,667 kD. p205 had one F-actin-binding domain at 1,631-1,829 aa residues and one PDZ domain at 1,016- 1,100 aa residues, a domain known to interact with transmembrane proteins. p205 was copurified from rat brain with another protein with a molecular mass of 190 kD (p190). p190 was a protein of 1,663 aa with a calculated molecular mass of 188,971 kD. p190 was a splicing variant of p205 having one PDZ domain at 1,009-1,093 aa residues but lacking the F-actin-binding domain. Homology search analysis revealed that the aa sequence of p190 showed 90% identity over the entire sequence with the product of the AF-6 gene, which was found to be fused to the ALL-1 gene, known to be involved in acute leukemia. p190 is likely to be a rat counterpart of human AF-6 protein. p205 bound along the sides of F-actin but hardly showed the F-actin-cross-linking activity. Northern and Western blot analyses showed that p205 was ubiquitously expressed in all the rat tissues examined, whereas p190 was specifically expressed in brain. Immunofluorescence and immunoelectron microscopic studies revealed that p205 was concentrated at cadherin-based cell-to-cell AJ of various tissues. We named p205 l-afadin (a large splicing variant of AF-6 protein localized at adherens junction) and p190 s-afadin (a small splicing variant of l-afadin). These results suggest that l-afadin serves as a linker of the actin cytoskeleton to the plasma membrane at cell-to-cell AJ.  相似文献   
898.
Clear powder coatings that consist of spherical particles with a narrow particle size distribution were produced via a suspension method that involves the agglomeration and unification of smaller particles. These powder coatings have the advantages of excellent powder flowability and high transfer efficiency. This behavior is attributable to the spherical particle shape and absence of finer particles. This production method has been developed for thinner film build clear coats with improved surface smoothness as compared to powder coatings produced by conventional methods.  相似文献   
899.
The fabrication and performance of a LiNbO3-based waveguide-type polarization controller with a Ti-indiffused waveguide along the z axis is reported. The device, designed for use at 1.55-μm wavelength and consisting of a TE/TM mode converter and a phase shifter in series, exhibited the half-wave voltages of 25 and 20 V for the TE/TM mode converter and the phase shifter, respectively. The modal birefringence and the behavior of the respective elements under applied fields are described in some detail. In addition, a preliminary performance test of the device was conducted by placing the device in a Mach-Zehnder interferometer  相似文献   
900.
A 3000/6000V, 1000 kVA class superconducting transformer (SC-Tr) was developed for a Prospective Power Transmission Model System Integrated under Superconducting Environment (PROMISE). In this transformer, the core and superconducting windings are immersed in liquid helium and the major insulation is provided by the liquid helium. This paper describes both the design features and measured characteristics of the SC-Tr. Fundamental characteristics of the SC-Tr are obtained through no-load, short-circuit tests and quench experiments. The results of the no-load test have verified that the SC-Tr has the capability to withstand ac voltage of 3000/6000 V of 60 Hz without any partial discharge. The short-circuit tests have proved that the SC-Tr is capable of carrying ac current of 170 Arms without quench in the superconducting windings. Furthermore, in a real-load experiment with the PROMISE, electric power of 3800 V-460 kVA of 50 Hz in high-voltage side is transmitted through this SC-Tr.  相似文献   
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