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1.
Amplification or overexpression of HER-2/neu in human lung cancer has been correlated with poor prognosis and chemoresistance. We have previously reported that the adenovirus type 5 early region 1A (E1A) gene product can suppress HER-2/neu-mediated transformation phenotypes through inhibition of HER-2/neu expression. To find an efficient way to treat HER-2/neu-overexpressing lung cancer with E1A, a replication-deficient adenovirus containing the E1A gene, Ad.E1A(+), was used to transduce E1A into HER-2/neu-overexpressing and low expressing human lung cancer cell lines. Tumour cell growth in vitro and colony formation in soft agarose were greatly inhibited by Ad.E1A(+) transduction in HER-2/neu-overexpressing lung cancer cell lines. In HER-2/neu low expressing cell lines, E1A could not inhibit cell growth in vitro but could reduce the colony formation ability in soft agarose, indicating different effects of E1A in these two types of cancer cells. To test the therapeutic efficacy of E1A to lung cancer by systemic delivery in vivo, tumor-bearing mice were established by intratracheal injection of lung cancer cells and treated by i.v. tail injections of Ad.E1A(+). As a result, Ad.E1A(+) suppressed HER-2/neu overexpression and inhibited intratracheal lung cancer growth. However, no significant tumor suppression effect of Ad.E1A(+) was observed in mice bearing HER-2/neu low expressing cell line when the same therapeutic procedure was followed. Thus, we conclude that systemic delivery of Ad.E1A(+) can efficiently achieve therapeutic effect in HER-2/neu-overexpressing lung cancer in vivo. 相似文献
2.
Taking advantage of the structure of logical representations, we report an algorithm that evaluates conjunctive queries in a massively parallel environment under an object-based representation for deductive databases. By distributing objects in a database, we show that parallel evaluation of a query can be achieved in a cooperative way so that the conventional tuple-by-tuple, operation-by-operation evaluation strategy can be replaced by a global, parallel matching approach. With the proposed scheme, all conjuncts of a given query can be examined at the same time, which enables us to eliminate the need of any temporary relation. On the other hand, compared with the interpretive method, we show that any data dependency imposed by shared variables is no longer a major problem in achieving AND-parallelism by the proposed scheme 相似文献
3.
The Synthesis of Sulfated Titanium Oxide Nanotubes 总被引:1,自引:0,他引:1
Chiu-Hsun Lin Shu-Hua Chien Jiunn-Hsing Chao Chyi-Yang Sheu Yu-Cheng Cheng Ya-Jean Huang Chih-Hsiang Tsai 《Catalysis Letters》2002,80(3-4):153-159
TiO2 nanotubes can be prepared in gram quantities by treating anatase TiO2 powder with concentrated NaOH solution. These TiO2 nanotubes acquired strong acidity after being impregnated with sulfuric acid solution and calcined at 300 °C. The anatase TiO2 powder used to prepare the nanotube did not catalyze the esterification between cyclohexanol and acetic acid, while sulfated TiO2 nanotubes were very reactive toward the esterification reaction. 相似文献
4.
A model for preventive maintenance operations and forecasting 总被引:2,自引:1,他引:1
Equipment costs constitute the greatest majority of overall costs for semiconductor manufacturing. Therefore, maintaining
high equipment availability has been regarded as one of the major goals in the industry. The ability to forecast correctly
equipment preventive maintenance (PM) timing requirements not only can help optimizing equipment uptime but also minimizing
negative impacts on manufacturing production efficiency. This research used grey theory and evaluation diagnosis to construct
a PM forecasting model for prediction of PM timing of various machines. The results showed significant improvements of PM
timing predictions compared to the existing method based on experience and an alternative method proposed by Li and Chang
(Semiconductor Manufacturing Technology Workshop 2002: 10–11, pp. 275–277) for the same fab cases.
Received: June 2005 / Accepted: December 2005 相似文献
5.
Effect of Thickness of the p-AlGaN Electron Blocking Layer on the Improvement of ESD Characteristics in GaN-Based LEDs 总被引:1,自引:0,他引:1
Chung-Hsun Jang Sheu J.K. Tsai C.M. Shei S.C. Lai W.C. Chang S.J. 《Photonics Technology Letters, IEEE》2008,20(13):1142-1144
The following letter presents a study regarding GaN-based light-emitting diodes (LEDs) with p-type AlGaN electron blocking layers (EBLs) of different thicknesses. The study revealed that the LEDs could endure higher electrostatic discharge (ESD) levels as the thickness of the AlGaN EBL increased. The observed improvement in the ESD endurance ability could be attributed to the fact that the thickened p-AlGaN EBL may partly fill the dislocation-related pits that occur on the surface of the InGaN-GaN multiple-quantum well (MQW) and that are due to the strain and the low-temperature-growth process. If these dislocation-related pits are not partly suppressed, they will eventually result in numerous surface pits associated with threading dislocations that intersect the InGaN-GaN (MQW), thereby reducing the ESD endurance ability. The results of the experiment show that the ESD endurance voltages could increase from 1500 to 6000 V when the thickness of the p-AlGaN EBL in the GaN LEDs is increased from 32.5 to 130 nm, while the forward voltages and light output powers remained almost the same. 相似文献
6.
Cheng-Hsiung Lid Shou-Chiung Chen Yung-Chi Lee Theodore D. Sokoloski Ming-Thau Sheu 《Drug development and industrial pharmacy》1994,20(11):1911-1922
Polyvinylpyrrolidone (PVP) in aqueous solution was used as a binding agent in a fluidized-bed system to agglomerate acetaminophen powder into directly compressible granules. It was found that a minimal amount of 5% w/w PVP in a concentration of 7.5% w/v or less was needed to produce granules with an acceptable flow and the corresponding tablets having enough hardness without capping. There was a strong correlation between the time for 80% dissolved (T80) and the logarithm of granule volume-surface mean diameter. A directly compressible acetaminophen composition to manufacture tablets having a T80 value less than 30 min can be prepared simply by adding an appropriate amount of disintegrant (crospovidone, sodium starch glycolate, or pregelatinized starch) to the agglomerated granules. 相似文献
7.
Neurological complications of radiotherapy and chemotherapy can affect the central or peripheral nervous system. Most are dose-dependent and constitute a limiting factor in the administration of treatments. Radiation-induced neurological complications are classified as acute, early-delayed or delayed. The most important are radionecrosis and cognitive dysfunction/leukoencephalopathy. Neurotoxicity of chemotherapy is frequent and depends upon dose, type of drugs (especially cisplatin and methotrexate) and their combination with radiotherapy. 相似文献
8.
JY Cesbron H Agut B Gosselin D Candotti M Rapha?l F Puech M Grandadam P Debré A Capron B Autran 《Canadian Metallurgical Quarterly》1994,317(7):669-674
HIV induces a multi-organ infection with a dual tropism for both lymphocytes and monocytes/macrophages. The lung is a target both for HIV infection and HIV-related opportunistic infections. The SCID mouse has provided the opportunity to develop a small animal model for HIV infection. However, HIV-1 infection of the human fetal thymus and liver (SCID Liv/Thy) implanted in these mice occurred only after direct intraimplant injection of HIV-1 and the resultant HIV-1 infection was restricted to the human thymus. Here we report that human foetal lung can develop in SCID Liv/Thy mice resulting in the development of normal human alveolar and bronchiolar lung compartments which can be productively infected with cell-free HIV-1 virus, leading to a systemic and bifocal infection. This SCID-Hu model should be useful for studying AIDS physiopathology, human viruses with lung tropism and for helping to define gene therapy protocols in lung human cells in vivo. 相似文献
9.
The analytical solutions of a spinning Rayleigh beam with rotatory moment inertia and gyroscopic effect are presented in this paper. The critical speeds can be written analytically in a function of the length-to-radius ratio (l) defined by the beam's length over its outer radius and the hollowness ratio (α) defined by the hollow area over the total area of the cross section. The sensitivity analyses show that the critical speed is decreasing with l, but increasing with α. Moreover, α is more sensitive to the critical speeds. The design of a spinning beam should therefore be emphasized more on the hollowness factor. Contrary to common belief, only finite critical speeds exist and the number is independent of the boundary conditions. It increases monotonically with l, but decreases with α. The steady state unbalanced response can therefore be expressed analytically by the finite precessional modes and the corresponding generalized coordinates. 相似文献
10.
K. T. Yu S. H. Sheu K. S. Chen 《The International Journal of Advanced Manufacturing Technology》2007,34(5-6):421-429
Recently, studies associated with testing the quality and performance of each process for a product with multi-characteristics
are proposed more often. However, most studies are limited to discussing one single type of quality characteristic. Practically,
a multi-characteristic product is potentially composed of three types: smaller-the-better, larger-the-better, and nominal-the-best.
In this paper, we propose an integrated product capability index which considers these three different types of quality characteristics.
According to the theory of testing hypothesis, we develop a testing procedure for the product capability index to judge whether
the process capabilities of total quality characteristics meet the customers’ demands. In addition, the relationship between
the product capability index and the yield of the entire product will be introduced. Finally, an example is provided as a
practical application. 相似文献