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1.
岩心PI值试验研究及应用 总被引:5,自引:0,他引:5
主要论述了在多功能采油化学用剂评价仪上进行的岩心PI值试验的步骤,现象及结论。重点考察了岩心PI值与渗透率、流量及注入截面面积的关系;平行管岩心复合PI值和其中单管岩心PI值的关系。 相似文献
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In response to the increasing trend toward community health care, a model of training that prepares students for community practice was incorporated into the occupational therapy curriculum at the University of Southern California. During academic training students are placed in a part-time community assignment where no occupational therapy services are offered. Training students for the role of community health specialist produces a dilemma for curriculum design. A balance must be achieved between providing traditional clinical content and providing the knowledge and expertise necessary for community practice. However, this training is considered necessary for maintaining the viability of the profession in a changing health system. Significantly, during the four-year period using this model, many graduates have sought employment in "nontraditional" community roles. 相似文献
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清洁生产是指不断采取改进设计、使用清洁的能源和原料、采用先进的工艺技术与设备、改善管理、综合利用等措施,从源头削减污染,提高资源(含能源)利用效率,减少或者避免生产、服务和产品使用过程中污染物的产生和排放。以减轻或者消除对人类健康和环境的危害。我国先后颁布了“中华人民共和国清洁生产促进法”和“清洁生产审核暂行办法”等法律法规。鼓励和促进清洁生产,以实现节能、降耗、减污、增效。为宣传在实施清洁生产过程中取得的成功经验,我刊将陆续刊登清洁生产实施案例以飨读者。同时欢迎您积极参与![编者按] 相似文献
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Plausible costs of photovoltaic power plants of concentration are presented. Costs are based as much as possible on the recent experience of solar thermal plants. Efficiencies, on the existing world experience of PV power plants. The result is that the costs of concentrating photovoltaic plants should be of 0.08 ECUs/ kWh, about 1/3 of that of flat module plants, and of the same order of magnitude, even lower, than those attributed to solar thermal plants of present technology. For the future, high concentration systems based on Si or tandem cells seem to be the most promising, also in the range of costs of the advanced solar thermal plants. 相似文献
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BACKGROUND: Synthetic homopyrimidine peptide nucleic acids (PNAs) can bind complementary targets in double-stranded DNA, generating strand-displacement complexes, and so offering an opportunity to modulate specific gene expression. Several issues remain to be addressed before these attributes can be exploited in vivo, however. RESULTS: The kinetics of the interaction between a homopyrimidine PNA and a complementary homopurine target on double-stranded DNA were analyzed in the presence or absence of a preformed strand-displacement complex proximal to the target. The complex was established under low salt conditions by the binding of a different homopyrimidine PNA to a target situated adjacent to the first PNA target. These two targets were placed next to each other on opposite strands at distances of 0, 2, 4 and 8 base pairs apart. The presence of a preformed strand-displacement complex near the target accelerates the binding of PNA to double-stranded DNA in a salt-dependent manner. The influence of salt on the binding rates was also examined. The binding rate is increased by a factor of 1 x exp(70[NaCl]), that is, 16-fold at 40 mM NaCl and more than 10(4)-fold if extrapolated to 140 mM NaCl. This effect is significantly reduced if the two targets are 2 base pairs apart and completely absent if the distance is 4 base pairs or more. CONCLUSIONS: The perturbation of the DNA helix imposed by a PNA strand-displacement complex only propagates a few base pairs. It is therefore possible to target sites in the immediate vicinity of strand invasion complexes specifically. The results presented have implications for the mechanism of strand displacement and for the application of PNA in a genomic context. 相似文献
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S Antinori L Galimberti GL Tadini AL Ridolfo C Parravicini R Esposito M Moroni 《Canadian Metallurgical Quarterly》1995,14(10):911-914
Two patients with AIDS and disseminated tuberculosis characterized by cutaneous involvement are reported. They developed a maculopapular skin eruption, from which a multidrug-resistant Mycobacterium tuberculosis strain was isolated. In both cases the clinical course was rapidly fatal. Tuberculosis cutis miliaris disseminata should be differentiated from the skin lesions frequently seen in HIV-infected patients, especially from folliculitis. In patients with tuberculosis, the appearance of cutaneous lesions may be due to the haematogenous dissemination of mycobacteria. Therefore, early identification of the causative organism by use of optimal microbiological methods is fundamental. 相似文献
9.
Ten families living in Shenyang city with multiple cases of essential hypertension were studied by HLA haplotype analysis. They were selected strictly in accordance with the methods of sibling pair analysis and lods analysis. The obtained ratio of HLA haplotype sharing among affected siblings were 28.6%(2): 52.4%(1): 19.0%(0), P > 0.9. It is indicated that the haplotype shared randomly among affected siblings. The results of Lods analysis were Q = 0.40, Lods = 0.046, Pr = 1.112. These results showed that there is no evidence of patients with essential hypertension susceptible to gene linked with HLA. 相似文献
10.
Employed a paired comparisons scaling technique to assess the preference of schizophrenics for varying quantities of information as presented in geometric forms. Both good premorbid paranoid and poor premorbid nonparanoid schizophrenics showed their greatest preference for the least complex shapes. Results are discussed in terms of H. Munsinger and W. Kessen's (see 39:2) conception of a match between preference for environmental information and input-processing capacity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献