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1.
Regulatory changes occurring early in colorectal cancer development remain poorly investigated. Since the majority of cases develop from polyps in the adenoma-carcinoma transition, a search of early molecular features, such as aberrations in miRNA expression occurring prior to cancer development, would enable identification of potentially causal, rather than consequential, candidates in the progression of polyp to cancer. In the current study, by employing small RNA-seq profiling of colon biopsy samples, we described differentially expressed miRNAs and their isoforms in the adenoma-carcinoma transition. Analysis of healthy-adenoma-carcinoma sequence in an independent validation group enabled us to identify early deregulated miRNAs including hsa-miR-1246 and hsa-miR-215-5p, the expressions of which are, respectively, gradually increasing and decreasing. Loss-of-function experiments revealed that inhibition of hsa-miR-1246 lead to reduced cell viability, colony formation, and migration rate, thereby indicating an oncogenic effect of this miRNA in vitro. Subsequent western blot and luciferase reporter assay provided evidence of hsa-miR-1246 being involved in the regulation of target AXIN2 and CFTR genes’ expression. To conclude, the present study revealed possible involvement of hsa-miR-1246 in early colorectal cancer development and regulation of tumor suppressors AXIN2 and CFTR.  相似文献   
2.
Investigations of Y1–x M x Ba2Cu3O7– (M=Ce, Th)c-axis oriented thin film specimens show that the rate of depression ofT c withx is larger for M=Th, than for M=Ce and Pr, and suggest that Ce, like Th, is tetravalent in this compound. Hall effect measurements on Y1–x Pr x Ba2Cu3O7– single crystals reveal aT 2 dependence of the cotangent of the Hall angle in the normal state and a negative Hall anomaly belowT c in the superconducting state, in agreement with recent reports. Our research shows that the depth, , of the negative Hall signal scales withT/T c and that the maximum value of decreases linearly withx and vanishes atx0.24. Magnetoresistance measurements on Y1–x Pr x Ba2Cu3O7– single crystals indicate that the irreversibility lineH(T *) obeys a universal scaling relation characterized by anm=3/2 power law nearT c, with a crossover to a more rapid temperature dependence of belowT/T c 0.6, similar to that observed for polycrystalline specimens.  相似文献   
3.
We describe transport experiments where the spatial gradient of the driving Lorentz force is controlled. The velocity profiles induced by the Lorentz force gradient in the driven liquid and lattice vortex phases are characteristic of hydrodynamic, plastic, and elastic motion.  相似文献   
4.
The purpose of this study was to analyse emulsions for vitamin D3 delivery in yoghurt and sour cream. Oil‐in‐water emulsions stabilised by whey proteins alone and by whey proteins plus carboxymethylcellulose were used. No change in vitamin D3 added to the yoghurt and sour cream in the form of both emulsions was observed after storage at 7 days in light and 14 days in dark at 4 °C. The results of bioavailability tests, using rats, for vitamin D3 from the fortified emulsions and yoghurt indicated that it is feasible to use stabilised emulsions as delivery systems of vitamin D3 in fortified products.  相似文献   
5.
Gastric cancer (GC) remains one of the most common causes of mortality worldwide. Intestinal metaplasia (IM) is one of the preneoplastic gastric lesions and is considered an essential predisposing factor in GC development. Here we present a review of recent most relevant papers to summarize major findings on the molecular alterations in gastric IM. The latest progress in novel diagnostic methods allows scientists to identify various types of molecular alterations in IM, such as polymorphisms in various genes, changes in the expression of micro-RNAs and long noncoding RNAs, and altered microbiome profiles. The results have shown that some of these alterations have strong associations with IM and a potential to be used for screening, treatment, and prognostic purposes; however, one of the most important limiting factors is the inhomogeneity of the studies. Therefore, further large-scale studies and clinical trials with standardized methods designed by multicenter consortiums are needed. As of today, various molecular alterations in IM could become a part of personalized medicine in the near future, which would help us deliver a personalized approach for each patient and identify those at risk of progression to GC.  相似文献   
6.
Laser-induced breakdown spectroscopy (LIBS) has been used to measure the equivalence ratio of a spark-ignited engine in a laboratory setting. Spectral features of C (711.3 nm), O (776.6 nm), N (746.3 and 743.8 nm), and CN (broad emission 707-734 nm) were used to quantify the equivalence ratio over a range from phi = 0.8 to phi = 1.2. The C/N and C/O peak ratios were found to be successful measurement metrics, compared with a standard exhaust gas oxygen analyzer, for averaged measurements. Some variation in the measurements was observed as a function of engine load. Single-shot data based on a CN/air peak ratio were evaluated using a separate calibration from averaged measurements, and the average of the single-shot data was found to agree well with the exhaust gas oxygen analyzer. The scatter in the single-shot data was substantially higher at lower equivalence ratios. The measurements including the CN peak were slightly sensitive to load, possibly due to pressure changes in the sample as the load increases, or possibly due to changes in the particle size distribution in the gas stream.  相似文献   
7.
This article reports what are to the authors' knowledge the first gas-phase laser-induced breakdown spectroscopy (LIBS) measurements using a fiber-optically delivered spark. A silver- and polymer-coated hollow fiber delivered high-energy nanosecond 1064 nm Nd:YAG laser pulses, which were focused to generate high-energy-density plasmas in ultra-lean methane-air mixtures. Emissions from these plasmas were collected and spectroscopically analyzed to quantify relative fuel-to-air ratio. These measurements were compared with others made using traditional LIBS techniques without the fiber-optically delivered spark. Similar results were obtained, but with larger shot-to-shot variability, for the case of the fiber-optically delivered spark.  相似文献   
8.
9.
The interest in potential applications produced with self-compacting fibre reinforced concrete continues to grow, but in practice, problems associated with an uneven distribution and orientation of fibres in the concrete structure occur. It is not clear what exactly influences uneven distribution of fibres in self-compacting concrete (SCC) mixtures, especially during the casting and how different factors influence fibre orientation. The objective of this work was to investigate how rheological properties influence the steel fibre distribution in self-compacting concrete. This work also focuses on the investigation of steel fibre spatial orientation dependence on rheological properties of SCC, while keeping other casting parameters and the proportions of mixture components constant. Mixtures with three different rheological properties were chosen based on slump flow, slump flow time t500 and static segregation values. The steel fibre orientation, volumetric concentration and spatial distribution values were determined in separate beam sections using three different non-destructive testing methods: electromagnetic induction, image analysis and computed tomography (CT scan). The comparison of the results is presented. The results show how different rheological properties of SCC affect the steel fibre orientation and distribution for the case of beams produced with the flow-induced casting method.  相似文献   
10.
Microsystem Technologies - In this article, thermal imprint process for replication of high-quality microstructures on the surface of polymer is investigated. Vibrations has been previously...  相似文献   
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