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961.
Causal attributions of hyperactive children: Implications for teaching strategies and self-control. 总被引:1,自引:0,他引:1
The combined influence of attribution and self-control training on the short- and long-term maintenance of strategic behavior, impulsivity, and beliefs about self-efficacy was assessed in 77 underachieving, hyperactive children. During 4 sessions, children in a self-control condition received self-management training and instructions in the use of interrogative and clustering rehearsal strategies. Children in a self-control plus attribution condition received the same instructions plus training designed to enhance general and program-specific beliefs about the importance of effort in improving performance. Children in a control condition were given strategy training but received no self-control or attribution instructions. Analysis of short-term treatment effects showed that children who received attribution training used more complex strategies, demonstrated higher personal causality scores endorsing effort, and displayed reduced impulsivity. Ten months following training, children in the self-control plus attribution condition persisted in their use of acquired strategies, maintained beliefs about the importance of effort, and displayed more mature memory knowledge. Severely hyperactive children, who had received the attributional boost, showed decreased hyperactivity in the classroom and improved self-control. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
962.
Differentially methylated sequences associated with imprinted genes are proposed to control genomic imprinting. A 2-kb region located 5' to the imprinted mouse H19 gene is hypermethylated on the inactive paternal allele throughout development. To determine whether this differentially methylated domain (DMD) is required for imprinted expression at the endogenous locus, we have generated mice harboring a 1.6-kb targeted deletion of the DMD and assayed for allelic expression of H19 and the linked, oppositely imprinted Igf2 gene. H19 is activated and Igf2 expression is reduced when the DMD deletion is paternally inherited; conversely, upon maternal transmission of the mutation, H19 expression is reduced and Igf2 is activated. Consistent with the DMD's hypothesized role of setting up the methylation imprint, the mutation also perturbs allele-specific methylation of the remaining H19 sequences. In conclusion, these experiments show that the H19 hypermethylated 5' flanking sequences are required to silence paternally derived H19. Additionally, these experiments demonstrate a novel role for the DMD on the maternal chromosome where it is required for the maximal expression of H19 and the silencing of Igf2. Thus, the H19 differentially methylated sequences are required for both H19 and Igf2 imprinting. 相似文献
963.
The automotive midrail is the main load carrying/energy absorbing component in a frontal vehicle crash. Three separate midrails, from three different manufacturers, each of a different size class of vehicle, and each with different crush modes, were found to exhibit the same sensitivity to variations in material thickness and stress-strain properties. From the results it was determined that a general design guideline for crashworthiness could be stated as: For every 10% change in thickness there is approximately a 14% change in energy absorption capability for a crushing midrail, while for every 10% change in material strength there is approximately a 7·3% change in energy absorption capability. The proposed design guideline can be used to help determine suitable modifications to make a structure more crashworthy and, additionally, to determine how manufacturing variations may affect the crashworthiness of a vehicle. 相似文献
964.
965.
An epidemiological study of equine sarcoid in a population of 4126 donkeys showed that the peak incidence of the disease was 15.2 cases per 100 animal-years and occurred in animals in their fourth year of life. The crude incidence of the disease was 0.6 cases per 100 animal-years. The disease occurred most frequently in younger, male animals during their first five years in the population. The lesions were observed most commonly in the paragenital region. Pre-entry quarantine procedures did not appear to play a significant role in the spread of the disease but there was an indication that close in-contact animals were more likely to have sarcoids than animals in the general population. This suggested that a transmissible agent might have been involved in the aetiopathogenesis or that the animals had encountered some event that had predisposed them to the disease. 相似文献
966.
A 23-year old woman with primary sclerosing cholangitis was being treated with ursodeoxycholic acid (URSO). When pregnancy was diagnosed, she was already through the first trimester. The treatment was discontinued, but her symptoms including severe pruritus recurred immediately, and the biochemical markers of bile duct obstruction worsened. It was necessary to start URSO-treatment again, which relieved her symptoms and improved the biochemistry. The remaining part of the pregnancy was uncomplicated, there were no malformations and so far, the baby is doing fine. URSO may be a possible treatment for severe intrahepatic cholestasis and pruritus during pregnancy. 相似文献
967.
968.
JX Yan L Tonella JC Sanchez MR Wilkins NH Packer AA Gooley DF Hochstrasser KL Williams 《Canadian Metallurgical Quarterly》1997,18(3-4):491-497
The cellular slime mold Dictyostelium discoideum is a eukaryotic microorganism which has developmental life stages attractive to the cell and molecular biologist. By displaying the two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) protein map of different developmental stages, the key molecules can be identified and characterised, allowing a detailed understanding of the D. discoideum proteome. Here we describe the preparation of reference gel of the D. discoideum multicellular aggregate, the slug. Proteins were separated by 2-D PAGE with immobilised pH gradients (pH 3.5-10) in the first dimension and sodium dodecyl sulfate (SDS)-PAGE in the second dimension. Micropreparative gels were electroblotted onto polyvinylidene difluoride (PVDF) membranes and 150 spots were visualised by amido black staining. Protein spots were excised and 31 were putatively identified by matching their amino acid composition, estimated isoelectric point (pI) and molecular weight (M(r)) against the SWISS-PROT database with the ExPASy AAcompID tool (http:// expasy.hcuge.ch/ch2d/aacompi.html). A total of 25 proteins were identified by matching against database entries for D. discoideum, and another six by cross-species matching against database entries for Saccharomyces cerevisiae proteins. This map will be available in the SWISS-2DPAGE database. 相似文献
969.
970.