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991.
Studied 107 female undergraduates who listened to 1 of 2 audiotaped recordings of a counseling interview between an experienced male counselor and a female client. Half of the Ss heard a tape containing counselor self-disclosure (S-D) statements; the other half heard a tape containing counselor self-involving (S-I) statements. Ss rated the counselor's expertness, attractiveness, and trustworthiness (Counselor Rating Form) and generated written responses to each S-D or S-I counselor statement. The S-I counselor was rated as significantly more expert and trustworthy than was the S-D counselor. Further, Ss' responses to the S-D counselor statements contained significantly more questions about and references to the counselor, whereas responses to S-I counselor statements contained significantly more self-referents. Ss' responses to the S-I counselor were significantly more likely to be phrased in the present, rather than the past or future, tense. Implications for the practice of counseling and for further research on self-disclosure are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
992.
OBJECTIVES: Monophosphoryl lipid A (MLA), a detoxified derivative of the lipid A portion of the endotoxin molecule, given as a pretreatment 24 h prior to cardiac ischemia/reperfusion reduces myocardial stunning and infarction in dogs. This study was undertaken to evaluate the ability of MLA pretreatment to reduce infarct size in a rabbit model of in situ regional myocardial ischemia and reperfusion. Secondly, the potential role of modulation of ATP-sensitive potassium (KATP) channel in MLA's cardioprotection was evaluated using in vivo pharmacologic antagonism with a KATP channel blocker, as was the role of tumor necrosis factor using an enzyme-linked immunosorbent assay method of serum cytokine analysis. METHODS: Rabbits were pretreated intravenously with MLA or vehicle injection 24 h prior to initiation of 30 min in situ left anterior descending coronary artery occlusion followed by 3 h reperfusion. In animals receiving glibenclamide, the potassium channel antagonist was administered 30 min prior to inducing ischemia. Animals receiving glibenclamide, which possesses hypoglycemic effects, underwent serial blood glucose evaluation prior to drug and throughout the ischemia and reperfusion periods. Hemodynamics were monitored; infarct size and area at risk were assessed by contrast dye staining (triphenyltetrazolium chloride). Serum tumor necrosis factor was measured by enzyme-linked immunosorbent method in animals administered cardioprotective doses of MLA as well as pyrogenic doses of MLA and endotoxin (positive control) to determine if elaboration of this cytokine could be associated with the cardioprotective effect of MLA. RESULTS: MLA administered as a single intravenous dose 24 h prior to ischemia reduced infarct size, expressed as a percent of the area at risk, 64 and 71% at doses of 35 and 10 micrograms/kg, respectively. Lower doses of MLA (2.5 and 5 micrograms/kg) did not significantly reduce infarct size. Administration of glibenclamide (300 micrograms/kg) 30 min prior to ischemia completely blocked the ability of MLA pretreatment to limit infarct size, while MLA vehicle-glibenclamide-treated control rabbits displayed infarcts not significantly different from MLA-vehicle-treated control rabbits. A cardioprotective dose of MLA (35 micrograms/kg) did not induce the elaboration of tumor necrosis factor into rabbit serum (within the limits of assay sensitivity). CONCLUSIONS: Single-dose pretreatment with MLA administered intravenously to rabbits substantially reduces infarct size when administered 24 h prior to ischemia. Pharmacologic preconditioning with MLA appears to be mediated through KATP channels as the channel blocker, glibenclamide, reversed the cardioprotective activity of MLA when administered 1 day following MLA pretreatment, yet 30 min prior to ischemia. In this model the cardioprotective does not appear to be associated with increases in serum tumor necrosis factor.  相似文献   
993.
994.
Innovations in Systems and Software Engineering - Many of the correctness properties afforded by task-parallel programming models such as OpenMP, Cilk, X10, Chapel, Habanero, etc. rely on data-race...  相似文献   
995.
Certain nutrients and growth factors can stimulate pancreatic beta-cell growth. However, the appropriate mitogenic signaling pathways in beta-cells have been relatively undefined. In this study, differential gene expression in NEDH rat insulinoma was compared with NEDH rat primary islet beta-cells. Differential mRNA display analysis revealed an elevated expression in insulinoma of VL30 transposons, S24 ribosomal protein, and cytochrome-C oxidaseVIIc that is typical for cells undergoing mitosis. A gene candidate approach revealed that mRNA levels of the oncogenes c-fos and c-jun were equivalently expressed in insulinoma and islet cells, as was the mRNA for the mitogenic signal transduction molecule insulin receptor substrate (IRS)-1. However, in contrast to that of IRS-1, IRS-2 gene expression was 60- to 70-fold higher in the insulinoma tissue compared with islets, which was reflected at the protein as well as the mRNA level. The specific elevated IRS-2 expression was a consistent observation across all rodent pancreatic beta-cell lines. To investigate whether IRS-2 was functional, serum-stimulated beta-cell proliferation was examined in isolated insulinoma cells. After a 48-h period of serum withdrawal, 24 h of serum refeeding rendered an 8- to 10-fold increase in [3H]thymidine incorporation into insulinoma cells. This serum-stimulated DNA synthesis was prevented by inhibitors of tyrosine protein kinase and phosphatidylinositol (PI) 3-kinase activities, as well as the activation of mitogen-activated protein (MAP) kinase and p70S6K. Examination of IRS-mediated signal transduction pathways indicated that after 10-15 min of serum refeeding, there was increased tyrosine phosphorylation of IRS-2 and pp60, and PI 3-kinase recruitment to IRS-2. Serum also increased the association of growth factor-bound protein 2/murine sons of sevenless 1 protein to a PI 3-kinase/IRS-2 protein complex. Moreover, serum also activated MAP-kinase (erk-1 and erk-2 isoforms) and 70 kD S6 kinase. Thus IRS-mediated signal transduction pathways are functional in pancreatic beta-cells. It is conceivable that IRS-2 expression in beta-cells contributes to maintaining the islet beta-cell population, complementary to observations in the IRS-2 knockout mouse in which beta-cell mass is markedly reduced.  相似文献   
996.
The findings of a review into European Creep Crack Growth practice relating to weldments are presented. Test piece design, test load control, temperature measurement, displacement determination, crack growth monitoring and the calculation of crack growth are examined. A draft code of practice to address CCG testing of weldments is reviewed and future developments in this field are explored.  相似文献   
997.
The effects of thermal treatment and zeolite proton concentration on the chemical state and metal particle size of zeolite Y supported ruthenium (3.0 wt%) have been investigated using H2-TPR, H2-TPD, TPMS, FTIR, TEM, and EXAFS. Heating in Ar of the precursor after ion exchange, [Ru(NH3)6]3+/NaY, up to 400°C leads to nearly 100% autoreduction of the ruthenium, as evidenced by H2-TPR and TPMS. Heating in O2 results in the formation of volatile ruthenium oxides. After autoreduction, the Ru clusters are extremely small, their coordination numbers, derived from EXAFS, are 0.6 for Ru/HY and 0.8 for Ru/NaY. Subsequent treatment at 500°C in flowing H2 induces Ru agglomeration to particles which are about the size of the zeolite Y supercages, as indicated by TEM and EXAFS. The Ru-Ru distances are contracted compared to bulk Ru metal. Washing of autoreduced Ru/NaY with NaOH, thus removing the protons formed during autoreduction, results in Ru agglomeration to large particles (60-100 Å). Comparison of the hydrogen adsorption of Ru clusters with similar sizes of 10-15 Å reveals a marked interaction of the Ru clusters with zeolite protons. Increasing the H+/Ru ratio from 3 for Ru/NaY to 10 for Ru/HY, results in a suppression of hydrogen chemisorption per Ru atom by 75%. The conclusion that formation of metal-proton adducts affects the electronic structure of the Ru clusters, thus being one of the main causes of the lowering of the heat of hydrogen chemisorption, is supported by FTIR data of adsorbed CO. The most pronounced C-O vibration band in Ru/HY is located at 2099 cm-1; this band is absent in Ru/NaY. Significant blue-shifting of the IR bands is in conformity with electron-deficiency of the Ru clusters in Ru/HY. The results confirm that adsorptive properties of zeolite encaged metal clusters can be "tuned" by other ions sharing the same cavities.  相似文献   
998.
Minor amounts of zirconia (up to 5 wt%) were fused with yttria and their effect on water solubility of yttria, and colloidal stability of yttria–silica aqueous binary suspensions, was examined. It is shown that incorporated zirconia reduces the water sensitivity of yttria while maintaining the hydrophilic nature of the surface. This fusion procedure makes yttria particles suitable for production of longlasting yttria–silica aqueous suspensions.  相似文献   
999.
The paper describes a study carried out to examine the effects of fly ash in limiting damaging sulfate-heave (swelling) in lime-stabilized soils. This considered three clays with various sulfate levels; seven fly ashes covering a range of physical and chemical properties, and stored under different conditions (dry, stockpiled and ponded); and a typical quicklime. The initial part of the study examined the effects of fly ash (applied at levels of 6 to 24% by mass of dry soil) on compaction (in terms of density/moisture relationships) of the lime-stabilized soils (using 3.0% lime) to establish mix compositions and provide an insight to their resulting structure. This indicated that maximum dry density (MDD) and optimum moisture content (OMC) were influenced by the characteristics of fly ash (reducing and increasing respectively with increasing fly ash coarseness and loss-on-ignition (LoI; including that under wet storage)) and, depending on these, by the level of application. Tests for sulfate-heave were made following the BS EN 13286-49 volumetric swelling method. Fly ash gave systematic reductions in sulfate-heave with increasing application level up to 24% for the lime-stabilized soils tested. It was found that coarse, high LoI fly ashes, stored under wet conditions, were most effective in limiting the process, suggesting that the coarser structure obtained during compaction with these materials, i.e. lower MDD, is an important factor influencing this. The presence of high sulfate levels in fly ash reduced the effectiveness of the material in this role. The practical implications are considered and a nomogram relating fly ash fineness and application level, MDD and sulfate-swelling is developed, which demonstrates a possible methodology for material selection with regard to minimizing damage.  相似文献   
1000.
The way children evaluate the reporting of peers' transgressions to authority figures was investigated. Participants, ages 6–11 years (N = 60), were presented with a series of vignettes, each of which depicted a child who committed either a minor transgression (such as not finishing the vegetables at lunch) or a more serious transgression (such as stealing from a classmate). Participants were asked to evaluate the decision of a child observer who either did or did not report the transgression to a teacher. Younger children considered reporting to be appropriate for both types of transgressions, but older children considered reporting to be appropriate for major transgressions only. Results are interpreted with reference to (a) a changing peer culture in which the social cost of reporting transgressions increases and (b) a developmental change in children's cognitive capabilities. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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