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71.
Currently, retinal pigment epithelium (RPE) transplantation includes sheet and single-cell transplantation, the latter of which includes cell death and may be highly immunogenic, and there are some issues to be improved in single-cell transplantation. Y-27632 is an inhibitor of Rho-associated protein kinase (ROCK), the downstream kinase of Rho. We herein investigated the effect of Y-27632 in vitro on retinal pigment epithelium derived from induced pluripotent stem cells (iPS-RPE cells), and also its effects in vivo on the transplantation of iPS-RPE cell suspensions. As a result, the addition of Y-27632 in vitro showed suppression of apoptosis, promotion of cell adhesion, and higher proliferation and pigmentation of iPS-RPE cells. Y-27632 also increased the viability of the transplant without showing obvious retinal toxicity in human iPS-RPE transplantation into monkey subretinal space in vivo. Therefore, it is possible that ROCK inhibitors can improve the engraftment of iPS-RPE cell suspensions after transplantation.  相似文献   
72.
This study focuses on the use of humanoid robots in office environments, and investigates whether a robot can maintain the attention of passersby after initiation of face-to-face contact. Drawing attention can be considered as a first step in improving the continuity of use of robots; such continuity is one factor in validating their social acceptance, which must be considered when disseminating robots in offices. In this study, we assume that the robot approaches and greets users in order to make the users aware of its presence and encourage them to use it. In particular, the robots used in this study convey various greetings along with three nonverbal indicators (no motion, random motion, and face-to-face contact) when a passerby at the office is close to the robot. For a one-week period, we validated the social acceptance of the robot by examining how these robot motions influenced the rate and continuity of a passerby's attention. The results revealed that face-to-face contact can draw a high degree of attention, and that the presence of the robot affects the continuity with which attention is drawn. Finally, the paper discusses implications for future robot design, in terms of drawing and maintaining high rates of attention from users.  相似文献   
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Alcohol use has been implicated as a risk factor for sexual negative consequences, such as unprotected sexual intercourse. The present research was conducted to examine the relationship between drinking protective behavioral strategies and consensual sex-related alcohol negative consequences, and whether this relationship varied by gender. Additionally, typical number of drinks during sexual behavior was evaluated as a potential mediator of this association. Heavy drinking, sexually active college students (N = 297, 50.2% women) completed self-report measures of drinking protective behavioral strategies, alcohol consumption, and sex-related alcohol negative consequences. Findings indicated that women who used drinking protective behavioral strategies more frequently were less likely to experience sex-related alcohol negative consequences whereas this relationship was not significant for men. For women, this relationship was mediated by the typical number of drinks consumed during sexual behavior. The current research demonstrates that use of drinking protective behavioral strategies is related to a reduction in women's sex-related risks when drinking. Findings are discussed in terms of alcohol myopia theory. Implications for interventions aimed to reduce higher risk sexual behavior among college students are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
Thermal fatigue crack growth in a fast breeder reactor is theoretically investigated with the aid of probabilistic fracture mechanics (PFM) under the conditions that (i) the temperature variation is a narrow-band stationary process and (ii) the crack grows owing only to the peak stress variation. First, a statistical property of residual life of the component with single crack is derived in an analytical form with the aid of an extended Markov approximation method, which is an efficient mathematical technique in PFM. Next, discussion is carried out on the generalization of the primitive model to the case with plural cracks, where a stress relaxation factor is introduced to express a stress intensity factor of each crack. Finally, a numerical example is shown to examine the quantitative behavior of the component's residual life, and sensitivity analysis is performed with respect to some model parameters.  相似文献   
76.
In glycoproteomics, key structural issues, protein identification, locations of glycosylation sites, and evaluation of the glycosylation site microheterogeneity should be easily evaluated in a large number of glycoproteins, while mass spectrometry (MS) provides substantial information about individual purified glycoproteins. Considering that structural issues are elucidated by studying glycopeptides and that the tandem MS of a tryptic peptide composed of several amino acid residues is enough for protein identification, construction of an MS-based method handling tryptic glycopeptides would be of considerable benefit in research. To this end, a simple and efficient method, utilizing hydrophilic binding of carbohydrate matrixes such as cellulose and Sepharose to oligosaccharides, was successfully applied to the isolation of tryptic glycopeptides. Both peptide and oligosaccharide structures were elucidated by multiple-stage tandem MS (MS(n)) of the ions generated by matrix-assisted laser desorption/ionization (MALDI), as follows. The MALDI ion trap mass spectrum of a tryptic glycopeptide mixture from N-linked glycoproteins was composed of the [M + H]+ ions of component glycopeptides. Collision-induced dissociation (CID) of the glycopeptide [M + H]+ ion generated saccharide-spaced peaks, with an interval of, for example, 146, 162, and 203 Da, and their fragment ions corresponding to the peptide and peptide + N-acetylglucosamine (GlcNAc) species in the MS2 spectrum. The saccharide-spaced ladder served to outline oligosaccharide structures, which were then selected as precursors for subsequent MS(n) analyses. The peptide or peptide + GlcNAc ions in the MS2 spectrum or the corresponding ions abundant in the MS1 spectrum were subjected to CID for determination of peptide sequences, to identify proteins and their glycosylation sites. The strategy, isolation of glycopeptides followed by MS(n) analysis, efficiently characterized the structures of beta2-glycoprotein I with four N-glycosylation sites and was applied to an analysis of total serum glycoproteins.  相似文献   
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78.
Characteristic tribological properties, such as nonlinearity of the friction force-normal load curve, high coefficient of friction, and good wear-resistant performance were observed on densely packed, vertically aligned carbon nanotubes (CNTs) with different diameters and lengths using atomic force microscopy. Shorter and thicker CNTs were found to have higher coefficients of friction. The observed properties were attributed to the nonlinear elastic property of the CNTs caused by buckling.  相似文献   
79.
The bromination of silk fabrics was studied under heterogeneous conditions in N,N-dimethylformamide using three reagent systems, molecular bromine, methanesulfonyl bromide (MsBr), and N-bromosuccinimide (NBS)-triphenylphosphine (PPh3) in combination with sodium bromide. Molecular bromine brominated tyrosine residues selectively and consecutively to 3-bromotyrosine and 3,5-dibromotyrosine residues. MsBr reacted only with serine residues to give 3-bromoalanine (Br-Ala) residues. The addition of sodium bromide to the NBS-PPh3 system suppressed the bromination of tyrosine residues and slightly increased the yield of Br-Ala residues. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2031–2036, 1997  相似文献   
80.
Poly(vinylidene fluoride) (PVdF) converts easily to thermally reversible gel at room temperature in aliphatic ketones or cyclic ketones such as 3-pentanone, 3-hexanone, cyclohexanone, and -butyrolactone, etc. Gelation of PVdF in these ketones took place through crystallization of polymers from solution. The crystallization process was investigated in detail by Fourier transform infrared (FTIR) measurements. The FTIR spectra were recorded continuously at room temperature until the solution converted to gel. It was suggested from spectral data that polymer chains packed together (i.e., crystallization took place) into the TTTGTTTG¯ conformation in the case of PVdF/γ-butyrolactone solution, followed immediately by gelation. On the other hand, crystallization occurred into the TGTG¯ conformation in the case of other ketones and gelation immediately took place. Melting temperatures of PVdF gels thus prepared from these solvents were measured. showed a solvent dependence. © 1997 John Wiley & Sons, Inc. J Appl Polm Sci 65:1517–1524, 1997  相似文献   
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