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91.
We locate the eye corners, eyelids, and irises in every frame of an image sequence, and analyze the movements of the irises and eyelids to determine changes in gaze direction and blinking, respectively. Using simple models for the motions of the head and eyes, we determine the head-independent motions of the irises and eyelids by stabilizing for the head motion. The head-independent motions of the irises can be used to determine behaviors like saccades and smooth pursuit. Tracking the upper eyelid and using the distance between its apex and the center of the iris, we detect instances of eye closure during blinking. In experiments on two short image sequences, in one of which the subject was wearing glasses, we successfully located the irises in every frame in which the eyes were fully or partially open, and successfully located the eyelids 80% of the time. When motion information in the form of normal flow was used, the irises were successfully tracked in every frame in which the eyes were fully or partially open, and the eyelids were successfully located and tracked 90% of the time. 相似文献
92.
93.
X-ray diffraction was utilized to follow the transformation from -SiC (3C) to the various -SiC polytypes in the presence of AlN and Al2O3 additives after hot pressing from 1700 to 2100°C. The 2H- and 6H-polytypes of -SiC were the predominate polytypes with additions of only AlN or Al2O3, respectively. The amount of 2H- and 6H-polytypes, and subsequently the microstructural morphology of the SiC materials, were found to be controlled by varying the amount of AlN and Al2O3. Improvements in fracture toughness to 9 MPa-m were achieved with flexural strengths ranging from 600 to 900 MPa. These results suggest that accurate control of the polytypic make-up of SiC-based materials, along with their mechanical properties, can be achieved through AlN and Al2O3 additions. 相似文献
94.
D Antonelli T Rosenfeld NA Freedberg E Palma JN Gross S Furman 《Canadian Metallurgical Quarterly》1998,21(2):418-421
Gag gene mutants of human immunodeficiency virus type 1 (HIV-1) were analyzed for their potentials of inhibiting the replication of wild-type (wt) HIV-2, the second AIDS virus, in a single-round of viral replication. Of twenty-two HIV-1 gag mutants examined, seven were found to efficiently interfere with the replication of wt HIV-2. Some mutants, which can suppress the replication of wt HIV-1, did not show this inhibitory effect. These mutants were defective at the late phase of viral replication. A mutant designated NL-C1a was demonstrated to be very effective against the replication of HIV-1 and HIV-2 in monocytic cells as well as in lymphocytic cells. 相似文献
95.
LK Bachrach K N?nto-Salonen P Tapanainen RG Rosenfeld SE Gargosky 《Canadian Metallurgical Quarterly》1995,5(2):109-118
OBJECTIVE: The study investigated the value of using national or regional data bases to examine care in a specific hospital. DATA SOURCES: The following data sources were included: (1) the results of the 1992 HCFA analysis of the index hospital for patients hospitalized in fiscal year 1990; (2) the 1989 Medicare Provider Analysis and Review (MEDPAR) file; and (3) clinical information from bypass surgery patients in Wisconsin and from the index hospital. PRINCIPAL FINDINGS: The assessment of the mortality rates in the index hospital for all conditions combined and for CABG patients differed depending on what data base was used and how the data were analysed. The national data were most useful in establishing that the coding practices for all patients and the mortality rate for intra-aortic balloon patients differed between the index hospital and other hospitals. The regional clinical data base for bypass surgery patients was used to establish that the high mortality rates for intra-aortic balloon patients were due to patient selection. CONCLUSIONS: National claims data must be analysed carefully before applying results to an individual hospital. Even a careful analysis is more for raising questions about care at a specific hospital rather than for reaching definitive conclusions. 相似文献
96.
TM Sugihara I Bach C Kioussi MG Rosenfeld B Andersen 《Canadian Metallurgical Quarterly》1998,95(26):15418-15423
Nuclear LIM domains interact with a family of coregulators referred to as Clim/Ldb/Nli. Although one family member, Clim-2/Ldb-1/Nli, is highly expressed in epidermal keratinocytes, no nuclear LIM domain factor is known to be expressed in epidermis. Therefore, we used the conserved LIM-interaction domain of Clim coregulators to screen for LIM domain factors in adult and embryonic mouse skin expression libraries and isolated a factor that is highly homologous to the previously described LIM-only proteins LMO-1, -2, and -3. This factor, referred to as LMO-4, is expressed in overlapping manner with Clim-2 in epidermis and in several other regions, including epithelial cells of the gastrointestinal, respiratory and genitourinary tracts, developing cartilage, pituitary gland, and discrete regions of the central and peripheral nervous system. Like LMO-2, LMO-4 interacts strongly with Clim factors via its LIM domain. Because LMO/Clim complexes are thought to regulate gene expression by associating with DNA-binding proteins, we used LMO-4 as a bait to screen for such DNA-binding proteins in epidermis and isolated the mouse homologue of Drosophila Deformed epidermal autoregulatory factor 1 (DEAF-1), a DNA-binding protein that interacts with regulatory sequences first described in the Deformed epidermal autoregulatory element. The interaction between LMO-4 and mouse DEAF-1 maps to a proline-rich C-terminal domain of mouse DEAF-1, distinct from the helix-loop-helix and GATA domains previously shown to interact with LMOs, thus defining an additional LIM-interacting domain. 相似文献
97.
Pathogenesis of oleic acid-induced lung injury in the rat: Distribution of oleic acid during injury and early endothelial cell changes 总被引:4,自引:0,他引:4
Greg Beilman 《Lipids》1995,30(9):817-823
Oleic acid-induced lung injury, a well-described laboratory model for acute pulmonary injury in the rat and other species,
causes morphologic and cellular changes similar to human adult respiratory distress syndrome (ARDS). Experiments were performed
to test the hypothesis that the initial event of oleic acid lung injury is damage of the pulmonary vascular endothelium by
oleic acid, with subsequent pulmonary damage and inflammation. Oleic acid levels were followed in the lung and other tissues
by measuring accumulation of14C-oleic acid; the direct effects of oleic acid and other fatty acids on rat endothelial cells, alveolar type II cells, and
hepatocytes in culture were determined. Lung tissue from treated rats was also examined by light and electron microscopy for
evidence of endothelial cell damage. At 30 min after injury, oleic acid reached high concentrations in lung tissue as demonstrated
by presence of radiolabel (3.24×10−6 moles per gram of tissue), with counts in the lung nearly an order of magnitude greater than in any other organ measured.
Oleic acid was present in the lung mostly as free fatty acid (85%), and was also present in the alveolar fluid supernatans,
rather than being cell-associated (1.7×10−7 moles vs. 1.1×10−8 moles at 30 min). Oleic acid was toxic to endothelial cells after one minute of exposure at concentrations of 5×10−4M and above. Electron microscopy showed endothelial cell changes as early as 10 min after induction of injuryin vivo, including the presence of endothelial cell blebbing. The results of these studies suggest that the initial event in oleic
acid lung injury is damage to the pulmonary vascular endothelial cell. 相似文献
98.
99.
Many languages make use of word-formation devices to allow speakers or writers to create new words when the existing vocabulary proves inadequate. In this paper we consider how these devices can be expressed formally, allowing them to be used in word- and sentence-generation, for dictionary expansion, and the like. The paper begins with some typical word-formation rules drawn mostly from French. Attention is drawn to some features of these rules which must be captured in any formal representation. The formal representation of a basic lexical transformation is presented in some detail, along with a number of examples. A computer implementation of the transformation system is described, together with a range of applications. A discussion of static and dynamic generation leads to the concept of an inverted transformation.Michael Levison is Professor and Head of the Department of Computing and Information Science at Queen's University at Kingston. His research interests currently centre on natural language generation and editing systems. He has written many articles on computer applications in literary and linguistic studies.Greg Lessard is an Associate Professor in the Department of French Studies at Queen's University. A linguist, his research interests include computational modelling of natural language performance (including second language learner French and linguistic humour) and computer-aided textual analysis (including repeated string and complex textual structures.) 相似文献
100.
A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner. 相似文献