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1.
Human papillomavirus (HPV) infection has been causally associated with cervical cancer. We tested the effectiveness of an HLA-A*0201-restricted, HPV-16 E7 lipopeptide vaccine in eliciting cellular immune responses in vivo in women with refractory cervical cancer. In a nonrandomized Phase I clinical trial, 12 women expressing the HLA-A2 allele with refractory cervical or vaginal cancer were vaccinated with four E786-93 lipopeptide inoculations at 3-week intervals. HLA-A2 subtyping was also performed, and HPV typing was assessed on tumor specimens. Induction of epitope-specific CD8+ T-lymphocyte (CTL) responses was analyzed using peripheral blood leukapheresis specimens obtained before and after vaccination. CTL specificity was measured by IFN-gamma release assay using HLA-A*0201 matched target cells. Clinical responses were assessed by physical examination and radiographic images. All HLA-A*0201 patients were able to mount a cellular immune response to a control peptide. E786-93-specific CTLs were elicited in 4 of 10 evaluable HLA-A*0201 subjects before vaccination, 5 of 7 evaluable HLA-A*0201 patients after two vaccinations, and 2 of 3 evaluable HLA-A*0201 cultures after all four inoculations. Two of three evaluable patients' CTLs converted from unreactive to reactive after administration of all four inoculations. There were no clinical responses or treatment toxicities. The ability to generate specific cellular immune responses is retained in patients with advanced cervical cancer. Vaccination with a lipidated HPV peptide epitope appears capable of safely augmenting CTL reactivity. Although enhancements of cellular immune responses are needed to achieve therapeutic utility in advanced cervical cancer, this approach might prove useful in treating preinvasive disease.  相似文献   
2.
An analogue of netropsin has been synthesized consisting of two N-propylpyrrolcarboxamide units linked covalently to a copper-chelating tripeptide Gly-Gly-L-His by means of two and three glycine residues. Binding to DNA and synthetic polynucleotides of netropsin analogue containing three glycine residues between Gly-Gly-L-His tripeptide and the N-end of netropsin analogue (His-Nt) has been studied. It is shown that this netropsin analogue chelates a copper ion with 1:1 stoichiometry, similar to a free Gly-Gly-L-His peptide. It is found that this netropsin analogue occupies 3 to 4 base pairs upon binding to poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers, irrespective of whether it binds in Cu(2+)-ligated or unligated forms. Binding constants and binding site sizes have been calculated for netropsin analogue complexes with DNA, poly(dA).poly(dT) and poly[d(AT)].poly[d(AT)] polymers at the [Cu2+]/[His-Nt] ratio equal to 0 and 1.0. In the three-component system including His-Nt and Cu(2+)-His-Nt, cooperative effects are recognized which can be explained by heterodimer generation on interaction of His-Nt and Cu(2+)-His-Nt at adjacent binding sites.  相似文献   
3.
膏体充填技术作为一种将选矿尾砂排放坑内采空区并形成坚固支承体的充填技术,从20世纪80年代初期就已经在加拿大地下矿山开始使用.然而,早期的膏体充填系统设备昂贵、能耗较高,使得地下矿山最近几年来开始探求一种更经济有效的充填技术.针对这个问题,现在已经研发出一种相应的技术,它能将选矿尾砂通过沉淀、浓缩和流态化过程制出膏体.加拿大矿物能源工艺中心(CANMET)在这种新工艺的研究中所取得的成果表明,选矿尾砂能在一个尾砂仓内通过浓缩和流态过程而制成膏体用于矿山充填.  相似文献   
4.
5.
In this paper we consider the problem of computing an mRNA sequence of maximal similarity for a given mRNA of secondary structure constraints, introduced by Backofen et al. in [R. Backofen, N.S. Narayanaswamy, F. Swidan, On the complexity of protein similarity search under mRNA structure constraints, in: Proceedings of the Annual Symposium of Theoretical Aspects of Computer Science, in: LNCS, vol. 2285, Springer, 2002, pp. 274-286] denoted as the MRSO problem. The problem is known to be NP-complete for planar associated implied structure graphs of vertex degree at most 3. In [G. Blin, G. Fertin, D. Hermelin, S. Vialette, Fixed-parameter algorithms for protein similarity search under mRNA structure constraints, in: Proceedings of Graph-Theoretical Concepts in Computer Science, in: LNCS, vol. 3787, Springer, 2005, pp. 271-282] a first polynomial dynamic programming algorithms for MRSO on implied structure graphs with maximum vertex degree 3 of bounded cut-width is shown.We give a simple but much more general polynomial dynamic programming solution for the MRSO problem for associated implied structure graphs of bounded clique-width. Our result implies that MRSO is polynomial for graphs of bounded tree-width, co-graphs, P4-sparse graphs, and distance hereditary graphs. Further we conclude that the problem of comparing two solutions for MRSO is hard for the class , which is defined as the set of problems which can be solved in polynomial time with a number of parallel queries to an oracle in NP.  相似文献   
6.
In this paper we give a finite forbidden subgraph characterization of graphs defined by NLC-width 2-expressions, by NLCT-width 2-expressions, or by linear NLC-width 2-expressions that have tree-width 1.  相似文献   
7.
A solar pond for annual cycle solar energy collection and storage was studied at The Ohio Agricultural Research and Development Center (OARDC), Wooster. It has been used as a thermal energy source for greenhouse heating. A brine-source electric-power-driven heat pump was incorporated into the heat extraction system. Initial results of the field studies indicated that the combined system improved the effectiveness of both the heat pump and the solar pond by enabling a larger temperature cycle within the solar pond.

To study the operation of such a system, a computer simulation model for the heating system was developed. The results of simulations were used to establish a relationship between the system performance and the present design and for sizing the solar energy collection and storage system. Also, the effect of a polystyrene pellet nighttime insulation for the greenhouse was simulated. Increasing the surface area of the OARDC pond was found to be less effective than changing its depth. Thr results showed that a 5 m deep pond with 1.0 m gradient zone significantly improved the overall performance of the system when used as a heat source for a heat pump. Based on the detailed experimental and computer simulation performance analysis, the solar pond-assisted heat pump system has the potential of improved performance compared with convential air source heat pumps.  相似文献   

8.
We perform linear stability calculations for horizontal fluid bilayers, taking into account both buoyancy effects and thermocapillary effects in the presence of a vertical temperature gradient. To help understand the mechanisms driving the instability, we have performed both long-wavelength and short-wavelength analyses. The mechanism for the large wavelength instability is complicated, and the detailed form of the expansion is found to depend on the Crispation and Bond numbers. The system also allows a conventional Rayleigh-Taylor instability if heavier fluid overlies lighter fluid, and the long-wavelength analysis describes this case as well. In addition to the asymptotic analyses for large and small wavelengths, we have performed numerical calculations using materials parameters for a benzene-water system.  相似文献   
9.
In this paper, a model is presented for predicting the phase modulation (PM) and amplitude modulation (AM) noise in bipolar junction transistor (BJT) amplifiers. The model correctly predicts the dependence of phase noise on the signal frequency (at a particular carrier offset frequency), explains the noise shaping of the phase noise about the signal frequency, and shows the functional dependence on the transistor parameters and the circuit parameters. Experimental studies on common emitter (CE) amplifiers have been used to validate the PM noise model at carrier frequencies between 10 and 100 MHz  相似文献   
10.
Modeling and testing a salt gradient solar pond in northeast Ohio   总被引:1,自引:0,他引:1  
A dynamic computer model of a salt gradient solar pond as an annual-cycle solar energy collection and storage system was developed. The model was validated using experimental results of a solar pond located at the Ohio Agricultural Research and Development Center (OARDC), Wooster, Ohio. The model was then used to analyze the transient energy phenomena which occurred within the storage zone of the pond. Generalized daily weather functions used were the incident solar radiation upon a horizontal surface, the daylight length and the daily maximum and minimum ambient air temperatures.Various simulations were performed to evaluate the OARDC solar pond and to improve its overall effective capacity of heat storage. It was found that 4–6 weeks variation in start-up time and 5–10°C variation in start-up temperature had no effect on late summer peak storage temperature. The pond operated at a 20 per cent collection efficiency with a 1.5-m deep gradient. Insulating the pond in the winter would be beneficial if no heat was removed during the fall. Reducing the gradient zone thickness to 1 m and enlarging the storage zone could improve the performance of a 3-m deep pond. The model could be used to predict and analyze the transient thermal response of large storages associated with solar heating system for a variety of purposes and climatic conditions.  相似文献   
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