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11.
We have established three cloned cell lines (COS1NR, COS2NR and COS4NR) from the lung metastatic nodule of a highly metastatic variant of rat transplantable osteosarcoma, C-SLM. All three clones shared the same morphological characteristics and tumorigenicity, but their growth rates in vitro and metastatic ability in vivo differed from each other. Single-strand conformation polymorphism (SSCP) analysis revealed all three clones to have the same p53 gene mutation and parent C-SLM tumor. On the other hand, Northern blot analysis showed a different pattern of expression for the genes, c-fos, c-jun, c-Ha-ras, transin (rat stromelysin), bone Gla protein (osteocalsin) and nm23/NDP kinase. These results indicate the presence of a heterogeneous cell population in terms of the different pattern of gene expression in a lung metastatic nodule of rat osteosarcoma and the present newly established cell lines will be useful for further investigation of the biological behavior of osteosarcomas.  相似文献   
12.
A commercially available recording of Northwestern University Auditory Test No. 6 (N.U. No. 6) produced by Auditec of St. Louis was evaluated in a series of four studies. Interlist equivalence of this version was initially investigated, and then normative intelligibility functions were developed using listerners with normal hearing. Intelligibility functions for the original version of N.U. No. 6. prepared by Northwestern University, were then derived, concurrently with functions of the Auditec version, using (1) a group of listeners with normal hearing; and (2) a group with sensorineural hearing loss. The results demonstrated good interlist equivalence for the Auditec version of N.U. No. 6. The comparative intelligibility functions for the Auditec and Northwestern versions of N.U. No 6 furthermore indicated a difference between the two recordings, but it was concluded that for clinical purposes the two versions may be considered equivalent.  相似文献   
13.
A new experimental apparatus, based on the laser-induced capillary wave method involving the use of a pulsed carbon dioxide laser (wavelength 10.6 m, pulse width 50 ns, power 65 mJ) as a heating source has been developed. Since the present technique is applicable to a wide range of viscosity, this method is applicable to the process in which the viscosity drastically changes within a short period of time. In this method, interfering laser beams heat a liquid surface and generate a capillary wave (the wavelength can be adjusted from 20 to 200 m) caused by a spatially sinusoidal temperature distribution. The temporal behavior of the capillary wave is detected by a diffracted probe beam (He–Ne laser, 15 mW) at the heated area. The dynamics of the capillary wave provide information regarding thermophysical properties such as viscosity and surface tension. In the present study, several liquid samples spanning the viscosity range from 0.33 to 7080 MPa·s (e.g., acetone, toluene, 1-hexanol, ethylene glycol, JS1000, and JS14000) were investigated at room temperature. The detected signals for several liquid samples exhibiting a wide range of viscosity agree well with theoretical calculations, taking into account the influence of the distribution of surface tension.  相似文献   
14.
The strains in an Al2O3/NiCr coating, which was thermally sprayed on SUS304 steel, were analyzed using an electronic speckle pattern interferometry (ESPI) system during fatigue testing (R = 0, max = 173 MPa) at high temperature of 873 K. The strain changes with the crack initiation in the coatings and the delamination at the coating/substrate interface are accordingly discussed.Surface cracks originated from the top coating of Al2O3 and stopped at the bond coating of NiCr after 2 cycles test at 873 K. Many surface cracks and delamination along the NiCr/substrate interface were confirmed after 1 × 105 cycles test. The strain values of un-sprayed specimens obtained from the ESPI system agreed with those measured by the strain gauge when tensile stresses were applied at room temperature. The deformation by thermal expansion and stress application at high temperatures can also be easily measured using this method. The strain on sprayed specimens was almost the same with that on un-sprayed specimens at 873 K, indicating the deformation in the coatings are always associated with that of the substrate surfaces at high temperature. By comparing and analyzing the strain distribution on the coating surface, the presence of cracks in the coatings and delamination at the coating/substrate interface can be in-situ and nondestructively detected.  相似文献   
15.
This communication considers a method for evaluating fluctuations in the integral type output of a linear time-invariant compartmental system with a Markovian transition process. First, we derived a mathematical formula to calculate variances and covariances of integral type. outputs, as with radioisotope data, when transition rates are known. Then, an estimate for the upper limits of variances and covariances, i.e., 1/2?initial dose, when the transition rates are not given beforehand, was introduced.  相似文献   
16.
3,5-Dipyrenylpyridine (PY1) and 2,6-dipyrenylpyridine (PY2) were synthesized to achieve not only efficient electron injection from cathode but also high electron mobility. The both of compounds showed much higher electron mobilities than that of Alq3, and have a similar ionization potential and electron affinity. However, the barrier height of electron injection from cathode to PY1 in an organic light emitting device was much smaller than that to PY2, probably due to the steric hindrance to the central pyridine group. These results suggest that the chemical affinity of electron-transporting materials with cathode is more important than their own electron affinity to improve the electron injection.  相似文献   
17.
18.
The aim of this study was to evaluate psychosocial quality of life after heart transplantation. We examined 29 patients (25 M and 4 F), average age was 43.5 y (18-62 y). The age at time of heart transplantation was 43 years (17-55 y). The time after heart transplantation was 3.3 year (0.3-9 y). Spielberger's Questionnaire of Anxiety, Knobloch's inventory of neuroticism, Freiburg's Personality Inventory and Quality of Life Inventory were used, 33% of patients demonstrated increasing frequency and 29% of patients increasing intensity of neurotic symptoms. 23% of patients presented increasing levels of anxiety (as a state). The personality dimensions (depression, excitability and low emotional stability) displayed high frequency. The results showed that patients were more satisfied with family support, with sexual activities, and less satisfied with financial situation, social activities, social isolations, sleep, memory, excitability, fatigue. 41.5% of patients returned back to work. The results indicate that these psychosocial factors play an important role in quality of life after heart transplantation. That is why if is necessary to dedicate an increasing attention to them. (Tab. 1, Fig. 6, Ref. 14.)  相似文献   
19.
Two genomic DNA clones that encode human indoleamine 2,3-dioxygenase (IDO) were isolated from the human genomic DNA library using the IDO cDNA as a probe, and their restriction maps and partial nucleotide sequences were determined. The human IDO gene spanned 15 kilobase pairs with ten exons. The 5' terminus of the IDO mRNA was 33 nucleotides upstream of the translation initiation codon ATG. The 5' flanking region contained ISRE, X-box, and Y-box like sequences. Southern blot analysis of the human genomic DNA indicated that the human IDO gene was present in a single copy in the genome.  相似文献   
20.
A series of (vinylphenyl)pyridine‐based polymer binders, PVPh2Py, PVPh3Py, and PVPh4Py, are designed and synthesized and it is found that mixtures of Liq and the polymers exhibit superior electron injection characteristics as ultrathin (1.6 nm) electron injection layer (EIL) films. They are comparable to those of EILs composed only of Liq. The addition of the polymers does not deteriorate the performance of Liq EILs. Additionally, when the EIL thickness is increased from 1.6 nm to 16 nm, the driving voltages increase and the external quantum efficiencies decrease. The increase in the voltage and decrease in the EQE are suppressed in the device with mixed EILs compared to those observed for the device composed of 100 wt% Liq. Furthermore, the position of the nitrogen in the pyridine ring is considered to influence the electron transport properties of the EILs. The mixing PVPh4Py with Liq improves the driving voltage of the fabricated devices, even with a thick mixed EIL. This reduced dependence of the performance of EILs on their thickness will be advantageous for the coating of large areas using solution processes.  相似文献   
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