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1.
In human leukemias and lymphomas nonrandom chromosomal rearrangements cause changes in cell growth and/or survival in such a way as to promote malignancy. The detailed study of the biochemical and genetic pathways altered in human cancer requires the identification or development of models to allow the study and manipulation of cancer gene function. Recently, the breakpoint gene TCL1, involved in chromosome translocations observed mostly in mature T-cell proliferations and chronic lymphocytic leukemias (CLL), was isolated and characterized, and showed to be part of a new gene family of proteins involved in these tumors. The murine Tcl1 gene, is similar in sequence to the murine and human MTCP1 gene also involved in T cell leukemias. The murine Tcl1 gene was shown to reside on mouse chromosome 12 in a region syntenic to human chromosome 14. Furthermore, we show that the murine Tcl1 gene is expressed early in mouse embryonic development and demonstrates expression in fetal hematopoietic organs as well as in immature T and B cells. Characterization of the murine Tcl1 gene will help in developing a mouse model of CLL and would provide the best opportunity to study and decipher the role of TCL1 in malignant transformation.  相似文献   
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Testing for syphilis during pregnancy reveals a positive serologic status in 0.02% of cases. However, a 66% rate of stillbirths is noted in women who are infected and who have not benefited from any treatment. Routine screening is at present performed during the early stages of pregnancy but a second serologic test during the third trimester is useful in the diagnosis of a late infection especially in drug users or HIV (human immunodeficiency virus) positive patients. Congenital syphilis is diagnosed in utero when a positive maternal serologic status is associated with ultrasound images showing fetal abnormalities; these include hepatosplenomegaly, hyperechogenic bowel, signs of bowel obstruction or fetal hydrops. Maternal syphilis is treated by delayed action penicillin and is indicated even for patients allergic to the antibiotic which in this particular case is delivered after desensitization. First line therapy by intravenous penicillin is indicated when confronted with the following high risk factors of congenital syphilis: an elevated titre of VDRL (venereal disease research laboratory) at the time of diagnosis or delivery, unknown date of the precise onset of the infection, the appearance of a rash or of a chancre during pregnancy, ultrasound fetal abnormalities or late therapy during the third trimester. Treatment of the new-born child will depend on the results of clinical, serologic and X-ray evaluation. Long term follow-up for at least a year is mandatory.  相似文献   
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The Journal of Supercomputing - General-purpose graphics processing units (GPGPUs) are extensively used in high-performance computing. However, it is well known that these devices’...  相似文献   
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Journal of Intelligent Information Systems - Conversational Recommender Systems have received widespread attention in both research and practice. They assist people in finding relevant and...  相似文献   
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The last advances on the application of INCA (Ionomer Nc Analysis) methodology for a better understanding of perfluorinated ionomers are reported and discussed. It was found that INCA is a very suitable technique for the determination of the melting temperature (Tm) of un-crystallized and semi-crystalline perfluorinated ionomers. Furthermore, for these determinations, it is even more precise than dynamic mechanical analysis, a method essentially developed for polymers in which the water-uptake is negligible. Of interest, it is the information that INCA methodology gives on the phenomenon of the water-uptake memory of perfluorinated ionomers.  相似文献   
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The rapid growth of the so-called Web 2.0 has changed the surfers’ behavior. A new democratic vision emerged, in which users can actively contribute to the evolution of the Web by producing new content or enriching the existing one with user generated metadata. In this context the use of tags, keywords freely chosen by users for describing and organizing resources, spread as a model for browsing and retrieving web contents. The success of that collaborative model is justified by two factors: firstly, information is organized in a way that closely reflects the users’ mental model; secondly, the absence of a controlled vocabulary reduces the users’ learning curve and allows the use of evolving vocabularies. Since tags are handled in a purely syntactical way, annotations provided by users generate a very sparse and noisy tag space that limits the effectiveness for complex tasks. Consequently, tag recommenders, with their ability of providing users with the most suitable tags for the resources to be annotated, recently emerged as a way of speeding up the process of tag convergence. The contribution of this work is a tag recommender system implementing both a collaborative and a content-based recommendation technique. The former exploits the user and community tagging behavior for producing recommendations, while the latter exploits some heuristics to extract tags directly from the textual content of resources. Results of experiments carried out on a dataset gathered from Bibsonomy show that hybrid recommendation strategies can outperform single ones and the way of combining them matters for obtaining more accurate results.  相似文献   
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In this work we perform a theoretical analysis of the thermoelectric performance of polycrystalline Si nanowires (NWs) by considering both electron and phonon transport. The simulations are calibrated with experimental data from monocrystalline and polycrystalline structures. We show that heavily doped polycrystalline NW structures with grain size below 100 nm might offer an alternative approach to achieve simultaneous thermal conductivity reduction and power factor improvements through improvements in the Seebeck coefficient. We find that deviations from the homogeneity of the channel and/or reduction in the diameter may provide strong reduction in the thermal conductivity. Interestingly, our calculations show that the Seebeck coefficient and consequently the power factor can be improved significantly once the polycrystalline geometry is properly optimized, while avoiding strong reduction in the electrical conductivity. In such a way, ZT values even higher than the ones reported for monocrystalline Si NWs can be achieved.  相似文献   
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