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991.
We examined the pregnancy outcome of 112 women classified as minor degrees of glucose intolerance (MDGI) in pregnancy in a screening program based on Carpenter and Coustan's criteria. The MDGI group comprised 49 women with abnormal oral glucose challenge test (OGCT) followed by normal OGTT (group A), and 63 with "borderline" OGTT (1 abnormal value, group B). No treatment was offered to 88 MDGI women, while 26 received dietary advice and metabolic monitoring. A control group was constituted from 112 age- and BMI-matched negative screenees. Similar rates of cesarean sections and macrosomia, but higher rate of large for gestational age (LGA) babies (25.9% vs 14.3%) were found in MDGI, without difference between groups A and B. When comparing treated and untreated MDGI, lower LGA incidence (11.5% vs 30.2%) and no macrosomia were found in the former. In conclusion, untreated MDGI may present excessive fetal growth, which can be normalized by dietary treatment and metabolic monitoring. 相似文献
992.
The toxic effects of the Fusarium graminearum trichothecene toxin deoxynivalenol were determined on ribosomes and leaf tissues of the fusarium head blight-resistant spring wheat cultivar Frontana and the susceptible spring wheat cultivar Casavant. The use of a poly-U-directed 14C-phenylalanine and deoxynivalenol ribosome-binding assays provided evidence of resistance to the protein-synthesis inhibition effects of deoxynivalenol in the head blight-resistant cultivar Frontana. This is probably due to the existence of a mutation in the peptidyl transferase. This cultivar also exhibited resistance to the membrane-damaging properties of this toxin compared to the other cultivar. This report summarizes the evidence for various kinds of "trichothecene tolerance" mechanisms in fusarium head blight-resistant wheat genotypes. 相似文献
993.
A Stoltzfus JM Logsdon JD Palmer WF Doolittle 《Canadian Metallurgical Quarterly》1997,94(20):10739-10744
Alignments of homologous genes typically reveal a great diversity of intron locations, far more than could fit comfortably in a single gene. Thus, a minority of these intron positions could be inherited from a single ancestral gene, but the larger share must be attributed to subsequent events of intron gain or intron "sliding" (movement from one position to another within a gene). Intron sliding has been argued from cases of discordant introns and from putative spatial clustering of intron positions. A list of 32 cases of discordant introns is presented here. Most of these cases are found to be artefactual. The spatial and phylogenetic distributions of intron positions from five published compilations of gene data, comprising 205 intron positions, have been examined systematically for evidence of intron sliding. The results suggest that sliding, if it occurs at all, has contributed little to the diversity of intron positions. 相似文献
994.
In this report, we describe the effect of staged bilateral posteroventral pallidotomy in three patients with advanced Parkinson's disease who were all of the young-onset type. Two patients had developed response fluctuations after the use of levodopa, with severe hypokinesia, painful dystonia, and rigidity in the "off" phase and violent dyskinesias in the "on" phase. One patient, in a continuous hypokinetic rigid state, was totally unresponsive to dopaminergic medication. All were at Hoehn and Yahr stage 5 in the "off" phase before surgery. After surgery, the hypokinetic state was reversed and dyskinesias were abolished in all patients. Hoehn and Yahr stages were 3 in the "off" phase postoperatively. Overall functional improvement was marked and lasting after follow-up for 7, 12, and 13 months, respectively. Complications were visual field deficit and transient central facial paresis, both in the same patient. Bilateral posteroventral pallidotomy can ameliorate response fluctuations, hypokinesia, rigidity, and painful dystonia in advanced Parkinson's disease. 相似文献
995.
RJ Landreneau DJ Sugarbaker MJ Mack SR Hazelrigg JD Luketich L Fetterman MJ Liptay S Bartley TM Boley RJ Keenan PF Ferson RJ Weyant KS Naunheim 《Canadian Metallurgical Quarterly》1997,113(4):691-8; discussion 698-700
BACKGROUND: The role of nonanatomic wedge resection in the management of stage I (T1 N0 M0) non-small-cell lung cancer continues to be debated against the present gold standard of care--anatomic lobectomy. METHODS: We analyzed the results of 219 consecutive patients with pathologic stage I (T1 N0 M0) non-small-cell lung cancer who underwent open wedge resection (n = 42), video-assisted wedge resection (n = 60), and lobectomy (n = 117) to assess morbidity, recurrence, and survival differences between these approaches. RESULTS: There were no differences among the three groups with regard to histologic tumor type. Analysis demonstrated the wedge resection groups to be significantly older and to have reduced pulmonary function despite a higher incidence of treatment for chronic obstructive pulmonary disease when compared with patients having lobectomy. The mean hospital stay was significantly less in the wedge resection groups. There were no operative deaths among patients having wedge resection; however, a 3% operative mortality occurred among patients having lobectomy (p = 0.20). Kaplan-Meier survival curves were nearly identical at 1 year (open wedge resection, 94%; video-assisted wedge resection, 95%; lobectomy, 91%). At 5 years survival was 58% for patients having open wedge resection, 65% for those having video-assisted wedge resection, and 70% for those having lobectomy. Log rank testing demonstrated significant differences between the survival curves during the 5-year period of study (p = 0.02). This difference was a result of a significantly greater non-cancer-related death rate by 5 years among patients having wedge resection (38% vs 18% for those having lobectomy; p = 0.014). CONCLUSION: Wedge resection, done by open thoracotomy or video-assisted techniques, appears to be a viable "compromise" surgical treatment of stage I (T1 N0 M0) non-small-cell lung cancer for patients with cardiopulmonary physiologic impairment. Because of the increased risk for local recurrence, anatomic lobectomy remains the surgical treatment of choice for patients with stage I non-small-cell lung cancer who have adequate physiologic reserve. 相似文献
996.
Simone Aparecida da Silva Lincoln Brum de Leite Gusmão Pinheiro Yuri Aparecido Opata João Frederico Haas Leandro Monteiro Francisco Carlos Serbena Gelson Biscaia de Souza Ezequiel Costa Siqueira Alcione Roberto Jurelo 《Journal of Superconductivity and Novel Magnetism》2018,31(8):2363-2372
This paper reports a study on the mechanical and tribological properties of ab- and a (b) c?planes of YBa2Cu3O7?δ single crystals. The single crystals were grown using a CuO-BaO self-flux method. The oxygenation effect on the mechanical and tribological properties of ab- and a (b) c?planes is reported. For the ab- plane, the hardness and elastic modulus were around 6 and 50 GPa, respectively. In this case, significant differences were not observed among the hardness and elastic modulus at different oxygenation states. However, the hardness and elastic modulus for as-grown and oxygenated YBa2Cu3O7?δ single crystals were different from that of the a (b) c?plane, and were observed to be slightly higher for the as-grown than for the oxygenated samples. For as-grown and oxygenated samples, we observed hardness values around 4.7 and 2.0 GPa, respectively. Regarding the elastic modulus, the values were 75 and 40 GPa, respectively. The indentation fracture toughness values on the ab- plane for the as-grown and oxygenated YBa2Cu3O7?δ single crystal were 3.7 ± 1.2 and 2.9 ± 1.2 MPa m1/2, respectively. For the ab- plane, the scratch resistance of the as-grown sample was higher than that of the oxygenated sample and the scratches under load were deeper for the oxygenated sample. As regards the a (b) c?plane, the scar features were seemingly constant through all the scratch lengths and the scratches under load were deeper and larger for the oxygenated than that for the as-grown sample. 相似文献
997.
JD Peterson LA Herzenberg K Vasquez C Waltenbaugh 《Canadian Metallurgical Quarterly》1998,95(6):3071-3076
Current thinking attributes the balance between T helper 1 (Th1) and Th2 cytokine response patterns in immune responses to the nature of the antigen, the genetic composition of the host, and the cytokines involved in the early interaction between T cells and antigen-presenting cells. Here we introduce glutathione, a tripeptide that regulates intracellular redox and other aspects of cell physiology, as a key regulatory element in this process. By using three different methods to deplete glutathione from T cell receptor transgenic and conventional mice and studying in vivo and/or in vitro responses to three distinct antigens, we show that glutathione levels in antigen-presenting cells determine whether Th1 or Th2 response patterns predominate. These findings present new insights into immune response alterations in HIV and other diseases. Further, they potentially offer an explanation for the well known differences in immune responses in "Th1" and "Th2" mouse strains. 相似文献
998.
Minds and Machines - I describe a suite of reinforcement learning environments in which artificial agents learn to value and respond to moral content and contexts. I illustrate the core principles... 相似文献
999.
George J. Piazza Raymond G. Bistline Jr. Alexander Bilyk Stephen H. Feairheller Michael J. Haas 《Journal of the American Oil Chemists' Society》1993,70(7):727-729
The butyl amide of ricinoleic acid (N-n-butyl-12-hydroxy-(9Z)-octadecenamide) was prepared from a neat mixture of castor oil andn-butylamine (fatty ester/amine molar ratio, 1:1.3). No catalyst was required. The identity and purity of the amide was assessed
by thin-layer chromatography and confirmed by elemental analysis and by infrared and C13 nuclear magnetic resonance spectroscopy. High product yields were achieved at 45 and 65°C in 48 and 20 h, respectively. The
reaction was inhibited by the addition of trimethylpentane and dioxane, but not by water. An attempt was made to prepare the
amide from methyl ricinoleate, rather than castor oil; even after 10 d only partial conversion was achieved. Attempts to prepare
the amide from methyl-n-butylamine, rather thann-butylamine, were also unsuccessful. The ease with which secondary fatty amides can be produced from an oil that consists
primarily of the glycerol esters of hydroxylated fatty acids indicates that the described procedure has industrial utility. 相似文献
1000.
Yong-Kwon Cho Carl T. Haas Katherine Liapi S. V. Sreenivasan 《Automation in Construction》2002,11(6):629-641
Rapid 3D positioning and modeling in construction can be used to more effectively plan, visualize, and communicate operations before execution. It can also help to optimize equipment operations, significantly improve safety, and enhance a remote operator's spatial perception of the workspace. A new framework for rapid local area sensing and 3D modeling for better planning and control of construction equipment operation is described and demonstrated. By combining human-assisted graphical workspace modeling with pre-stored Computer-Aided Design (CAD) models and simple sensors (such as single-axis laser rangefinders and remote video cameras), modeling time can be significantly reduced while potentially increasing modeling accuracy. 相似文献