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41.
The objective of this paper is to outline the potential threats to security and privacy that are associated with biometric-enabled applications, to summarize the resulting requirements to ensure secure and private handling of personal data, and to explain why standardization in this area is required. The currently ongoing standardization efforts in ISO/IEC in the area of biometric template protection are described.  相似文献   
42.
Recent years have seen a manifest increase in the use of modelling by the embedded systems industry. UML and SysML are two examples of languages used in this context. One of the reasons why the use of models is interesting is the possibility to perform early verification, validation and testing. A lot of work was devoted to developing theoretical results in verification and validation, and interesting results are available. Integrating these results in frameworks that take high-level models as an entry remains a challenging task, for several reasons that include the difficult scalability of the theoretical results. In previous work, we presented OMEGA 2, a framework that takes this challenge. Applying our framework on large industrial models revealed the fact that some features of the UML/SysML semantics which lead to bottlenecks in verification are not actually necessary in the models that we considered, thus leaving place for optimisations. This paper discusses the gap existing between the choices made in the general UML/SysML semantic framework and the actual needs of the users. We illustrate it based on the semantics of ports, for which we give a simplified version of the semantics. This semantics was implemented in our tools and we quantify the optimisation obtained when applying it to a set of case studies.  相似文献   
43.
《北京宣言行动纲领》鼓励政府和其他参与者在他们所有的政策和计划里积极显著地推动性别平等方针。  相似文献   
44.
Almost a decade has passed since the OMG has issued the Model Driven Architecture (MDA) initiative. It soon became obvious that raising the level of abstraction in development and reasoning at the model level would help in asking the right questions at the right time. Based on a concrete problem, we discuss four alternative solutions to a multi-language system design problem. These solutions use a traditional approach, a technique based on modeling, a domain-specific approach, and a mix of modeling and domain-specific techniques, respectively. The solutions depend on the problem, but they are representative for the situations we encounter in practice, therefore giving us a good basis for a larger discussion on the appropriateness of using modeling techniques and on the place of MDA in current software engineering practice and design.  相似文献   
45.
46.
The Bridging Sheet domain of HIV-1 gp120 is highly conserved among the HIV-1 strains and allows HIV-1 binding to host cells via the HIV-1 coreceptors. Further, the bridging sheet domain is a major target to neutralize HIV-1 infection. We rationally designed four linear peptide epitopes that mimic the three-dimensional structure of bridging sheet by using molecular modeling. Chemically synthesized peptides BS3 and BS4 showed a fair degree of antigenicity when tested in ELISA with IgG purified from HIV(+) broadly neutralizing sera while the production of synthetic peptides BS1 and BS2 failed due to their high degree of hydrophobicity. To overcome this limitation, we linked all four BS peptides to the COOH-terminus of GST protein to test both their antigenicity and immunogenicity. Only the BS1 peptide showed good antigenicity; however, no envelope specific antibodies were elicited upon mice immunization. Therefore we performed further analyses by linking BS1 peptide to the NH2-terminus of the E2 scaffold from the Geobacillus Stearothermophylus PDH complex. The E2-BS1 fusion peptide showed good antigenic results, however only one immunized rabbit elicited good antibody titers towards both the monomeric and oligomeric viral envelope glycoprotein (Env). In addition, moderate neutralizing antibodies response was elicited against two HIV-1 clade B and one clade C primary isolates. These preliminary data validate the peptide mimotope approach as a promising tool to obtain an effective HIV-1 vaccine.  相似文献   
47.
Anabolic androgenic steroids have become a major class of drugs of abuse among a growing population of male and female adolescents. Although the rewarding and reinforcing properties of androgens have been demonstrated in male rodents, it is unknown whether these properties are apparent in female rats. In this study, conditioned place preference and self-administration paradigms showed that the endogenous androgen metabolite 3αDIOL is rewarding and reinforcing in ovariectomized female rats. Because 3αDIOL can be synthesized de novo in the brain, it is hypothesized that this neurosteroid provides a permissive neurochemical environment that modulates reward processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
48.
Peptide-modified silver nanoparticles have been coated with an erbium-doped silica layer using a method inspired by silica biomineralization. Electron microscopy and small-angle X-ray scattering confirm the presence of an Ag/peptide core and silica shell. The erbium is present as small Er(2)O(3) particles in and on the silica shell. Raman, IR, UV-Vis, and circular dichroism spectroscopies show that the peptide is still present after shell formation and the nanoparticles conserve a chiral plasmon resonance. Magnetic measurements find a paramagnetic behavior. In vitro tests using a macrophage cell line model show that the resulting multicomponent nanoparticles have a low toxicity for macrophages, even on partial dissolution of the silica shell.  相似文献   
49.
Given the pharmacological properti es and the potential role of kynurenic acid (KYNA) in human physiology and the pleiotropic activity of the neurohormone melatonin (MEL) involved in physiological and immunological functions and as regulator of antioxidant enzymes, this study aimed at evaluating the capability of Saccharomyces cerevisiae EC1118 to release tryptophan derivatives (dTRPs) from the kynurenine (KYN) and melatonin pathways. The setting up of the spectroscopic and chromatographic conditions for the quantification of the dTRPs in LC-MS/MS system, the optimization of dTRPs’ production in fermentative and whole-cell biotransformation approaches and the production of dTRPs in a soybean-based cultural medium naturally enriched in tryptophan, as a case of study, were included in the experimental plan. Variable amounts of dTRPs, with a prevalence of metabolites of the KYN pathway, were detected. The LC-MS/MS analysis showed that the compound synthesized at highest concentration is KYNA that reached 9.146 ± 0.585 mg/L in fermentation trials in a chemically defined medium at 400 mg/L TRP. Further experiments in a soybean-based medium confirm KYNA as the main dTRPs, whereas the other dTRPs reached very lower concentrations. While detectable quantities of melatonin were never observed, two MEL isomers were successfully measured in laboratory media.  相似文献   
50.
With increasing global health threats has come an urgent need to rapidly develop and deploy safe and effective therapies. A common practice to fast track clinical adoption of compounds for new indications is to repurpose already approved therapeutics; however, many compounds considered safe to a specific application or population may elicit undesirable side effects when the dosage, usage directives, and/or clinical context are changed. For example, progenitor and developing cells may have different susceptibilities than mature dormant cells, which may yet be different than mature active cells. Thus, in vitro test systems should reflect the cellular context of the native cell: developing, nascent, or functionally active. To that end, we have developed high-throughput, two- and three-dimensional human induced pluripotent stem cell (hiPSC)-derived neural screening platforms that reflect different neurodevelopmental stages. As a proof of concept, we implemented this in vitro human system to swiftly identify the potential neurotoxicity profiles of 29 therapeutic compounds that could be repurposed as anti-virals. Interestingly, many compounds displayed high toxicity on early-stage neural tissues but not on later stages. Compounds with the safest overall viability profiles were further evaluated for functional assessment in a high-throughput calcium flux assay. Of the 29 drugs tested, only four did not modulate or have other potentially toxic effects on the developing or mature neurospheroids across all the tested dosages. These results highlight the importance of employing human neural cultures at different stages of development to fully understand the neurotoxicity profile of potential therapeutics across normal ontogeny.  相似文献   
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