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31.
Patients with ulcerative colitis (UC) have an increased risk for developing colorectal cancer. Because UC tumorigenesis is associated with genomic field defects that can extend throughout the entire colon, including the non‐dysplastic mucosa, we hypothesized that the same field defects will include abnormally expressed proteins. Here, we applied proteomics to study the protein expression of UC neoplastic progression. The protein profiles of colonic epithelium were compared with (i) UC patients without dysplasia (non‐progressors), (ii) non‐dysplastic colonic tissue from UC patient with high‐grade dysplasia or cancer (progressors), (iii) high‐grade dysplastic tissue from UC progressors, and (iv) normal colon. We identified differential protein expression associated with UC neoplastic progression. Proteins relating to mitochondria, oxidative activity, and calcium‐binding proteins were some of the interesting classes of these proteins. Network analysis discovered that Sp1 and c‐myc proteins may play roles in UC early and late stages of neoplastic progression, respectively. Two over‐expressed proteins in the non‐dysplastic tissue of UC progressors, carbamoyl‐phosphate synthase 1 and S100P, were further confirmed by immunohistochemistry analysis. Our study provides insight into the molecular events associated with UC neoplastic progression, which could be exploited for the development of protein biomarkers in fields of non‐dysplastic mucosa that identify a patient's risk for UC dysplasia.  相似文献   
32.
Ethanol damages the cell membrane and functional proteins, gradually reducing cell viability, and leading to cell death during fermentation which impairs effective bioethanol production by budding yeast Saccharomyces cerevisiae. To obtain more suitable strains for bioethanol production and to gain a better understanding of ethanol tolerance, ethanol-tolerant mutants were isolated using the novel mutagenesis technique based on the disparity theory of evolution. According to this theory evolution can be accelerated by affecting the lagging-strand synthesis in which DNA polymerase δ is involved. Expression of the pol3-01 gene, a proofreading-deficient of DNA polymerase δ, in S. cerevisiae W303-1A grown under conditions of increasing ethanol concentration resulted in three ethanol-tolerant mutants (YFY1, YFY2 and YFY3), which could grow in medium containing 13% ethanol. Ethanol productivity also increased in YFY strains compared to the wild-type strain in medium containing 25% glucose. Cell morphology of YFY strain cells was normal even in the presence of 8% ethanol, whereas W303-1A cells were expanded by a big vacuole. Furthermore, two of these mutants were also resistant to high-temperature, Calcofluor white and NaCl. Expression levels of TPS1 and TSL1, which are responsible for trehalose biosynthesis, were higher in YFY strains relative to W303-1A, resulting in high levels of intracellular trehalose in YFY strains. This contributed to the multiple-stress tolerance that makes YFY strains suitable for the production of bioethanol.  相似文献   
33.
The objective of this research is to propose a practical method of determining the background luminance in the evaluation of discomfort glare. Two experiments were conducted, a visual sensitivity test and a glare sensitivity test. The results show that the luminance of threshold and the luminance of discomfort glare are mainly determined by the luminance of the immediate background of the source, rather than by the average background luminance, which has previously been suggested by unified glare rating and visual comfort probability method. Consequently, when the background contains areas of differing luminance, the background luminance of a glare source should be determined by the local background luminance affecting the local adaptation.  相似文献   
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Summary Ordered microporous films were fabricated on the process of solvent evaporation for the solution of amphiphilic poly(acrylic acid)-block-polystyrene under a humid atmosphere. Pore size and its distribution are strongly dependent on the nature of polymers and the evaporation conditions. Poly(aniline) dots were also successfully fabricated via electropolymerization of aniline using a microporous film on indium tin oxide electrode as a template.  相似文献   
36.
The structure and localization of the microtubule organization centres (MTOCs) of the fission yeast Schizosaccharomyces japonicus var. japonicus were examined by fluorescence microscopy and electron microscopy. Spindle pole bodies (SPBs), which are the fungal equivalent of centrosomes, of Sz. japonicus were visualized by immunofluorescent staining using a monoclonal anti-gamma-tubulin antibody. The behaviour of the SPBs during the cell cycle mostly coincided with previous reports on the most widely used fission yeast Schizosaccharomyces pombe. We cloned the gamma-tubulin gene from Sz. japonicus by PCR using redundant sets of primers corresponding to conserved regions of known gamma-tubulins. The predicted amino acid sequence of Sz. japonicus gamma-tubulin was most similar to the Sz. pombe gamma-tubulin. Under the electron microscope, the SPBs of Sz. japonicus were detected as electron-dense multilayered structures located just outside the nuclear envelope. The SPBs of Sz. japonicus were composed of three electron-dense layers and were surrounded by fuzzy material. Each layer showed structural changes according to the progression of the cell cycle. In mitotic cells, the SPBs were located on the fenestrae of the nuclear envelopes through which the mitotic spindle microtubules ran into the nucleoplasm. Our results show that Sz. japonicus is a very potent and attractive organism for the investigation of the microtubule nucleation system and morphogenesis in yeasts. The Accession No. for the nucleotide sequence of the Sz. japonicus gtb1(+) gene is AF159163.  相似文献   
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Abstract— A multi‐view depth‐fused 3‐D (DFD) display that provides smooth motion parallax for wide viewing angles is proposed. A conventional DFD display consists of a stack of two transparent emitting screens. It can produce motion parallax for small changes in observation angle, but its viewing zone is rather narrow due to the split images it provides in inclined views. On the other hand, even though multi‐view 3‐D displays have a wide viewing angle, motion parallax in them is discrete, depending on the number of views they show. By applying a stacked structure to multi‐view 3‐D displays, a wide‐viewing‐angle 3‐D display with smooth motion parallax was fabricated. Experimental results confirmed the viewing‐zone connection of DFD displays while the calculated results show the feasibility of stacked multi‐view displays.  相似文献   
39.
The formation of complexes between thiamine disulfide (TDS) orO-acetyl thiamine disulfide (O-acetyl TDS) and fatty acid or fatty acid methyl ester in methanol has been studied by fluorescence quenching and13C NMR relaxation (T1) measurements. The association constants (K-values) of TDS andO-acetyl TDS with fatty acids (from 11∶0 to 18∶0, and 18∶1, 18∶2, 18∶3 and 20∶4) and fatty acid methyl esters have been determined. These values do not depend on either the number of carbon atoms or the degree of unsaturation of the fatty acid. The K-values of TDS andO-acetyl TDS with fatty acid were 7.8 M−1 and 5.1 M−1, respectively. The K-values of TDS andO-acetyl TDS with fatty acid methyl ester were very small. These results show that the-OH moiety in TDS and the-COOH moiety in the fatty acid are necessary for formation of the complex  相似文献   
40.
X-ray fluorescence analysis is a highly useful technique for determining the chemical composition of matter. The present article describes the successful development of a wavelength-dispersive x-ray fluorescence spectrometer for a fairly high-energy range, 30-60 keV, that can contribute to studying lanthanides' Kbeta spectra with high-energy resolution. By combining a new high-energy synchrotron light source and the present spectrometer, it has been demonstrated that the full width at half maximum for lanthanum's Kbeta(1) is 32 eV and that all the peaks in the spectra are fully resolved. This corresponds to an energy resolution EDeltaE of 1180, which is ten times better than a conventional system based on a Ge detector, which can detect only two peaks, Kbeta(1) and Kbeta(2), in seven peaks. The present spectrometer can open up a new field in x-ray spectrometry.  相似文献   
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