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41.
The fractional uptake of intact monoclonal antibodies by tumors is relatively low. Various methods to alter the molecular structure have been used to augment tumor uptake. These chemical manipulations, however, may alter the specificity of antibody binding. METHODS: Comparative studies of biodistribution, radioimmunoimaging and macroautoradiography in LC-6 xenografted mice were conducted with the 125I-labeled intact and N-terminal deglycosylated monoclonal antibodies to evaluate the effect on deglycosylation on antibody binding. RESULTS: The removal of N-glycosyl residues from this monoclonal antibody significantly enhanced specific localization of the radioactivity to the tumor, especially to its necrotic fraction. Nonspecific accumulation of radioactivity to the necrotic fraction of the tumor was excluded by biodistribution studies demonstrating selective accumulation of 125I-labeled monoclonal antibody after coadministration of 125I-monoclonal antibody (intact or N-deglycosylated) with 131I-labeled control IgM. CONCLUSION: The lung cancer-associated human monoclonal antibody HB4C5, which recognizes histone H2B as the antigen, accumulates specifically to the necrotic fraction of tumor. The uptake is enhanced by removal of N-terminal glycosyl residues from the antigen-binding site of the light chain.  相似文献   
42.
A central bronchogenic cyst was excised thoracoscopically from a 44-year-old woman in whom a tumor had been pointed out in the left upper posterior mediastinum at a screening examination. Since the tumor was diagnosed to be benign, only conservative follow-up was undertaken, but the patient consulted our department desiring active therapy. On the basis of the chest CT and MRI findings a bronchogenic cyst was diagnosed. Under general anesthesia and mechanical ventilation of one lung, the thoracoscope was inserted into the thoracic cavity revealing in the left upper posterior mediastinum a cyst which was excised thoracoscopically. While coagulation was performed gingerly with an electric scalpel, the tumor was detached sharply and bluntly with a pair of scissors. The postoperative course was uneventful with little wound pain or scar formation. Hitherto bronchogenic cysts have been treated by resection after thoracotomy. Although this is an easy procedure, a relatively large operative scar is left and considerable wound pain may develop. In contrast, thoracoscopic treatment is characterized by minimal surgical invasiveness, little postoperative wound pain, and small scars. These advantages suggest that this technique may be indicated for benign mediastinal tumors, particularly cysts.  相似文献   
43.
Materials such as expanded polytetrafluoroethylene and glutaraldehyde‐fixed bovine pericardium are currently used for cardiac tissue regeneration. However, patches made from these materials remain permanently without being absorbed by the body and must be replaced overtime because of degeneration or lack of growth. To improve the long‐term outcomes for cardiac tissue regeneration, biocompatible and biodegradable materials must be used. In this study, we used two biocompatible polymers, silk fibroin (SF), which is biodegradable and segmented polyurethane, to prepare nonwoven sheets that were then insolubilized by water vapor or methanol treatment. The tensile stress increased significantly on adding segmented polyurethane to pure SF and the water vapor processed sheets showed higher extension on strain than the methanol‐processed sheets. The different insolubilization treatments also resulted in different SF structures. Our results show that it is possible to obtain the physical properties required for cardiac tissue repair patch by varying the insolubilization treatment. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45560.  相似文献   
44.
Comparing polyaluminum chloride and ferric chloride for antimony removal   总被引:9,自引:0,他引:9  
Kang M  Kamei T  Magara Y 《Water research》2003,37(17):4171-4179
Antimony has been one of the contaminants required to be regulated, however, only limited information has been collected to date regarding antimony removal by polyaluminium chloride (PACl) and ferric chloride (FC). Accordingly, the possible use of coagulation by PACl or FC for antimony removal was investigated. Jar tests were used to determine the effects of solution pH, coagulant dosage, and pre-chlorination on the removal of various antimony species. Although high-efficiency antimony removal by aluminum coagulation has been expected because antimony is similar to arsenic in that both antimony and arsenic are a kind of metalloid in group V of the periodic chart, this study indicated: (1) removal density (arsenic or antimony removed per mg coagulant) for antimony by PACl was about one forty-fifth as low as observed for As(V); (2) although the removal of both Sb(III) and Sb(V) by coagulation with FC was much higher than that of PACl, a high coagulant dose of 10.5mg of FeL(-1) at optimal pH of 5.0 was still not sufficient to meet the standard antimony level of 2 microg as SbL(-1) for drinking water when around 6 microg as SbL(-1) were initially present. Consequently, investigation of a more appropriate treatment process is necessary to develop economical Sb reduction; (3) although previous studies concluded that As(V) is more effectively removed than As(III), this study showed that the removal of Sb(III) by coagulation with FC was much more pronounced than that of Sb(V); (4) oxidation of Sb(III) with chlorine decreased the ability of FC to remove antimony. Accordingly, natural water containing Sb(III) under anoxic condition should be coagulated without pre-oxidation.  相似文献   
45.
Nanocrystalline lanthanum hexaboride (LaB(6)) films have been deposited on molybdenum foil by the pulsed laser deposition (PLD) technique. The as-deposited films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM). The XRD pattern shows the cubic crystallinity of the LaB(6) film. The AFM studies reveal that the conical shaped LaB(6) nanostructures have height 60?nm, base 800?nm, and a typical radius of curvature ~20?nm. A comparison of force and in situ current imaging AFM studies reveals that current contrast does not originate from the surface topography of the LaB(6) film. Field emission studies have been performed in the planar diode configuration. A current density of 4.4 × 10(-2)?A?cm(-2) is drawn from the actual emitting area. The Fowler-Nordheim plot is found to be linear, in accordance with the quantum mechanical tunneling phenomenon. The field enhancement factor is estimated to be 3585, indicating that the field emission is from LaB(6) nanocrystallites present on the emitter surface, as confirmed by the AFM. The emission current-time plots show current stability to the extent of 5% fluctuation about the average current over a period of 3?h.  相似文献   
46.
An efficient method to calculate the lattice sums is presented for a one-dimensional (1-D) periodic array of line sources. The method is based on the recurrence relations for Hankel functions and the Fourier integral representation of the zeroth-order Hankel function. The lattice sums of arbitrary high order are then expressed by an integral of elementary functions, which is easily computed using a simple scheme of numerical integration. The calculated lattice sums are used to evaluate the free-space periodic Green's function. The numerical results show that the proposed method provides a highly accurate evaluation of the Green's function with far less computation time, even when the observation point is located near the plane of the array  相似文献   
47.
Silk is a protein fiber used to weave fabrics and as a biomaterial in medical applications. Recently, genetically modified silks have been produced from transgenic silkworms. In the present study, transgenic silkworms for the mass production of three colors of fluorescent silks, (green, red, and orange) are generated using a vector originating from the fibroin H chain gene and a classical breeding method. The suitability of the recombinant silks for making fabrics is investigated by harvesting large amounts of the cocoons, obtained from rearing over 20 thousand silkworms. The application of low temperature and a weakly alkaline solution for cooking and reeling enables the production of silk fiber without loss of color. The maximum strain tolerated and Young's modulus of the fluorescent silks are similar to those of ordinary silk, although the maximum stress value of the recombinant silk is slightly lower than that of the control. Fabrics with fluorescent color are demonstrated using the recombinant silk, with the color persisting for over two years. The results indicate that large amounts of genetically modified silk can be made by transgenic silkworms, and the silk is applicable as functional silk fiber for making fabrics and for use in medical applications.  相似文献   
48.
The number of diabetes mellitus (DM) patients is increasing, and stroke is deeply associated with DM. Recently, neuroprotective effects of glucagon-like peptide-1 (GLP-1) are reported. In this study, we explored whether liraglutide, a GLP-1 analogue exerts therapeutic effects on a rat stroke model. Wistar rats received occlusion of the middle cerebral artery for 90 min. At one hour after reperfusion, liraglutide or saline was administered intraperitoneally. Modified Bederson’s test was performed at 1 and 24 h and, subsequently, rats were euthanized for histological investigation. Peripheral blood was obtained for measurement of blood glucose level and evaluation of oxidative stress. Brain tissues were collected to evaluate the level of vascular endothelial growth factor (VEGF). The behavioral scores of liraglutide-treated rats were significantly better than those of control rats. Infarct volumes of liraglutide-treated rats at were reduced, compared with those of control rats. The level of derivatives of reactive oxygen metabolite was lower in liraglutide-treated rats. VEGF level of liraglutide-treated rats in the cortex, but not in the striatum significantly increased, compared to that of control rats. In conclusion, this is the first study to demonstrate neuroprotective effects of liraglutide on cerebral ischemia through anti-oxidative effects and VEGF upregulation.  相似文献   
49.
In this paper, experimentally determined pressure drop and heat transfer characteristics of flow of water in a 75-start spirally grooved tube with twisted tape insert are presented. Laminar to fully turbulent ranges of Reynolds numbers have been considered. The grooves are clockwise with respect to the direction of flow. Compared to smooth tube, the heat transfer enhancement due to spiral grooves is further augmented by inserting twisted tapes having twist ratios Y ? 10.15, 7.95 and 3.4. It is found that the direction of twist (clockwise and anticlockwise) influences the thermo-hydraulic characteristics. Constant pumping power comparisons with smooth tube characteristics show that in spirally grooved tube with and without twisted tape, heat transfer increases considerably in laminar and moderately in turbulent range of Reynolds numbers. However, for the bare spiral tube and for spiral tube with anticlockwise twisted tape (Y = 10.15), reduction in heat transfer is noticed over a transition range of Reynolds numbers.  相似文献   
50.
The effect of ratcheting on fatigue strength was investigated in order to rationalize the strain limit as a design criterion of commercialized fast reactor systems. Ratcheting fatigue tests were conducted at 550 °C. Duration of the ratchet straining was set for a certain number of strain cycles taking the loading condition of fast reactors into account, and the number of cycles for strain accumulation was defined as the ratchet-expired cycle. Fatigue lives decrease as the accumulated strain by ratcheting increases. Mean stress increased during the ratcheting cycle and its maximum value depended on the accumulated strain and the ratchet-expired cycle. Fatigue life reduction was negligible when the maximum mean stress was less than 25 MPa, corresponding to an accumulated strain of 2.2%. Accumulated strain is limited to 2% in the present design guidelines and this strain limit is considered effective to avoid reducing fatigue life by ratcheting. Microcrack growth behaviors were also investigated in these tests in order to discuss the life reduction mechanisms in ratcheting conditions.  相似文献   
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