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D-Allose is one of the rare sugars produced from D-psicose. We examined whether d-allose reduces the extent of rat renal ischemia/reperfusion (I/R) injury by suppressing the activation of neutrophils. The renal concentrations of cytokine-induced neutrophil chemoattractant (CINC)-1 and myeloperoxidase were significantly increased after renal I/R. These increases were significantly inhibited by D-allose administration. Furthermore, D-allose significantly inhibited the increase in the concentrations of blood urea nitrogen (BUN), creatinine, N-acetyl beta-D-glucosaminidase (NAG) and histopathologic changes after renal I/R. These findings strongly suggest that D-allose protects against I/R-induced renal injury by inhibiting the activation of neutrophils that play an important role in I/R-induced renal injury. These findings may have important implications in understanding the biologic functions of D-allose. D-Allose may prove useful in renal surgery and transplantation.  相似文献   
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Poly(vinyl chloride) (PVC) plastisol is used in many industrial applications and is considered an electrically inactive material. To explore the potential of plastisol as an electroactive material, the dielectric properties, space charge distribution, mechanical properties, internal structure and electromechanical behavior of plasticized PVC (PVC gel) prepared from plastisol by heating were investigated. The gel exhibited a large dielectric constant at low frequencies (1–1000 Hz), an asymmetric charge distribution and excellent mechanical properties. Various DC electric fields were applied to the gel placed parallel between two electrodes and the electrostatic adhesive force to the anode was measured. The results of small‐ and wide‐angle X‐ray scattering suggested that the electromechanical properties of the gel originated from the characteristics of the physical crosslinking distance (ca 20 nm) of PVC in the gel structure. Considering the dielectric properties, space charge density and adhesion force to the anode, PVC gels prepared from plastisol using the heating method have potential for use as electroactive materials. © 2013 Society of Chemical Industry  相似文献   
144.
Mechanical cues of cellular microenvironments can modulate cell functions including cell spreading and differentiation. Most studies of cellular functions are performed using a solid substrate, and it is thought that cells cannot spread on fluid substrates because of rapid relaxation, which cannot resist against actomyosin‐based cell contractility. Here, the spreading and growth of anchorage‐dependent cells such as human mesenchymal stem cells at the liquid interface between a perfluorocarbon fluid and the culture medium are observed. It is demonstrated that a monomolecular protein nanosheet self‐assembled at a fluid interface is sufficiently rigid to support cell spreading without additional treatment. Fine tuning of the packing of these proteins at the liquid interface permits tailoring of the mechanics of the protein layer, ultimately allowing for the regulation of cell spreading. The greater stiffness of the protein nanosheets triggers cell spreading, adhesion growth, and yes‐associated protein nuclear translocation. Cell behavior at the fluid interface is explained within the framework of the molecular clutch model. In addition, the freestanding ultrathin protein nanosheets are extremely flexible, easily deformed, and perceived by cells as being much softer. The findings are expected to provide a new perspective for insights into cell–material interactions.  相似文献   
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The surface properties and antiplatelet adhesion behavior of terminally functionalized hyperbranched poly(l -lactide)s (HB PLLAn-Glu, n = 5, 10, 20) were examined. Contact angle changes and X-ray photoelectron spectroscopic measurements indicated that the hydrated glutamic acid units in HB PLLAn-Glu films migrated to the surface during immersing in water and unique microdomains were observed from the HB PLLA10-Glu film after water immersion. HB PLLA10-Glu and HB PLLA5-Glu prevented platelet adhesion, but HB PLLA20-Glu showed the typical platelet adhesion response for a hydrophobic surface. Both the high hydrophilicity and microdomain formation of HB PLLAn-Glu contributed to the efficient antiplatelet adhesion behavior. The glutamic acid-terminated HB PLLA10-Glu films were more effective at preventing platelet adhesion than the 2-methoxyethoxy-terminated HB PLLA10 films. This study is the first example of platelet adhesion properties being controlled by the terminal functional groups and branching density of hyperbranched polymers. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46910.  相似文献   
146.
BACKGROUND and PURPOSE: The neck clipping of cerebral aneurysms is a well-established treatment for subarachnoid hemorrhage (SAH) caused by aneurysmal rupture. However, it is still unclear how great a risk of recurrence patients with a successfully treated aneurysm carry over a long-term period. METHODS: Of 425 patients with SAH surgically treated in Aizu Chuou Hospital from 1976 to 1994, 220 cases meeting the following criteria were studied: (1) all aneurysms detected by 3- or 4-vessel cerebral angiography were clipped, (2) complete obliteration of aneurysm(s) was confirmed by postoperative angiography, and (3) the patient survived >3 years. All patients were traced until January 1998 for recurrent SAH or death. The mean follow-up period was 9.9 (range, 3 to 21) years. RESULTS: Six patients (2.7%) had recurrent SAH, each with an interval ranging from 3 to 17 years (mean, 11 years) since the original treatment. In addition, 2 patients were found to have regrowth of the originally operated aneurysms. The cumulative recurrence rate of SAH, calculated using the Kaplan-Meier method, was 2.2% at 10 years and 9. 0% at 20 years after the original treatment. CONCLUSIONS: The recurrence rate was considerably higher than the previously reported risk of SAH in the normal population, and the rate increased with time. These data indicate that patients with ruptured cerebral aneurysms still carry higher risks for SAH in a long-term period, even after complete obliteration of the aneurysm, and that periodic examination to detect recurrent aneurysms may be indicated for such patients.  相似文献   
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Object substitution masking is a form of visual backward masking in which a briefly presented target is rendered invisible by a lingering mask that is too sparse to produce lower image-level interference. Recent studies suggested the importance of an updating process in a higher object-level representation, which should rely on the processing of visual motion, in this masking. Repetitive transcranial magnetic stimulation (rTMS) was used to investigate whether functional suppression of motion processing would selectively reduce substitution masking. rTMS-induced transient functional disruption of cortical area V5/MT+, which is important for motion analysis, or V1, which is reciprocally connected with V5/MT+, produced recovery from masking, whereas sham stimulation did not. Furthermore, masking remained undiminished following rTMS over the region 2 cm posterior to V5/MT+, ruling out nonspecific effects of real stimulation and confirming regional specificity of the rTMS effect. The results suggest that object continuity via the normal function of the visual motion processing system might in part contribute to this masking. The relation of these findings to the reentrant processing view of object substitution masking and other visual phenomena is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
150.
The dependence of the Hall coefficient RH of vacuum-deposited copper films of thickness, temperature and time was investigated by in situ observation. RH values were found to be larger than the bulk value and a thickness dependence could hardly be observed down to 100 Å. The temperature dependence was appreciably larger than for bulk material, indicating the existence of the size effect predicted by Sondheimer. RH for very thin films (below 100 Å) left in the vacuum system at 295°K changed with time, and the change was ascribed to the annihilation of lattice defects in the films.  相似文献   
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