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51.
Razia Noreen Chia-Chi Chien Hsiang-Hsin Chen Vladimir Bobroff Michel Moenner Sophie Javerzat Yeukuang Hwu Cyril Petibois 《Analytical and bioanalytical chemistry》2013,405(27):8729-8736
Evidence has recently emerged that solid and diffuse tumors produce a specific extracellular matrix (ECM) for division and diffusion, also developing a specific interface with microvasculature. This ECM is mainly composed of collagens and their scaffolding appears to drive tumor growth. Although collagens are not easily analyzable by UV-fluorescence means, FTIR imaging has appeared as a valuable tool to characterize collagen contents in tissues, specially the brain, where ECM is normally devoid of collagen proteins. Here, we used FTIR imaging to characterize collagen content changes in growing glioma tumors. We could determine that C6-derived solid tumors presented high content of triple helix after 8–11 days of growth (typical of collagen fibrils formation; 8/8 tumor samples; 91 % of total variance), and further turned to larger α-helix (days 12–15; 9/10 of tumors; 94 % of variance) and β-turns (day 18–21; 7/8 tumors; 97 % of variance) contents, which suggest the incorporation of non-fibrillar collagen types in ECM, a sign of more and more organized collagen scaffold along tumor progression. The growth of tumors was also associated to the level of collagen produced (P?<?0.05). This study thus confirms that collagen scaffolding is a major event accompanying the angiogenic shift and faster tumor growth in solid glioma phenotypes. 相似文献
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The charge-temperature technique was used to investigate the oxide properties of silicon MOS capacitors fabricated on a wafer with an oxide thickness of 660 Å. The stretchout of high frequencyC — V curve of the capacitor after a positive charge-temperature aging was proved to be due to the lateral nonuniformities of mobile charges and the increase of interface traps. The effect of lateral nonuniformitites was found to be successfully described by a model consisting of two parallelly connected nonuniform capacitors. The only parameter of importance is their area ratio, which can be easily determined by theoretical fitting. The appearance of a negative equivalent interface trap density was proposed as a new method to directly identify the existence of lateral nonuniformities. 相似文献
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Huang CC Lo YW Kuo WS Hwu JR Su WC Shieh DB Yeh CS 《Langmuir : the ACS journal of surfaces and colloids》2008,24(15):8309-8313
Of the methods employed in the preparation of one-dimensional lanthanide phosphate (LnPO(4)) nanorods/nanowires, such as GdPO(4), the hydrothermal method has been mainly used as a synthetic route. In this study, we report a facile low-temperature solution approach to prepare GdPO 4*H(2)O nanorods by simply refluxing GdCl(3) and KH(2)PO(4) for only 15 min at 88 degrees C, an approach that can easily be scaled up by increasing the reagent amounts. We observed a highly viscous macroscopic hydrogel-like material when we mixed as-prepared GdPO(4)*H(2)O nanomaterials with H(2)O. Hydrogels are an important class of biomaterials. Their building blocks, normally formed from protein-, peptide-, polymer-, and lipid-based materials, offer three-dimensional scaffolds for drug delivery, tissue engineering, and biosensors. Our preliminary results showed that GdPO(4)*H(2)O hydrogels could be used for encapsulation and drug release, and that they were biocompatible, acting as scaffolds to foster cell proliferation. These findings suggested that they might have biomedical uses. Our findings may lead to the creation of other inorganic nanomaterial-based hydrogels apart from the organic and biomolecular protein-, peptide-, polymer-, and lipid-based building blocks. 相似文献
56.
Bosco FG Hwu ET Chen CH Keller S Bache M Jakobsen MH Hwang IS Boisen A 《Lab on a chip》2011,11(14):2411-2416
Sensors are crucial in many daily operations including security, environmental control, human diagnostics and patient monitoring. Screening and online monitoring require reliable and high-throughput sensing. We report on the demonstration of a high-throughput label-free sensor platform utilizing cantilever based sensors. These sensors have often been acclaimed to facilitate highly parallelized operation. Unfortunately, so far no concept has been presented which offers large datasets as well as easy liquid sample handling. We use optics and mechanics from a DVD player to handle liquid samples and to read-out cantilever deflection and resonant frequency. Also, surface roughness is measured. When combined with cantilever deflection the roughness is discovered to hold valuable additional information on specific and unspecific binding events. In a few minutes, 30 liquid samples can be analyzed in parallel, each by 24 cantilever-based sensors. The approach was used to detect the binding of streptavidin and antibodies. 相似文献
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Just a spoonful of sugar! A new synthetic strategy involving the use of a deoxygenative olefination reaction as the key step was developed for the preparation of deoxy and iminosugars in their optically active form (see scheme). This strategy has been proven successful by the use of a pentose, hexose, heptose, and disaccharide as the starting materials. Furthermore, it was applied in a formal total synthesis of iminosugar (-)-1-deoxy-L-fuconojirimycin, which can inhibit α-L-fucosidase. 相似文献
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Y. T. Chen T. N. Lo C. W. Chiu J. Y. Wang C. L. Wang C. J. Liu S. R. Wu S. T. Jeng C. C. Yang J. Shiue C. H. Chen Y. Hwu G. C. Yin H. M. Lin J. H. Je G. Margaritondo 《Journal of synchrotron radiation》2008,15(2):170-175
The fabrication of gold Fresnel zone plates, by a combination of e‐beam lithography and electrodeposition, with a 30 nm outermost zone width and a 450 nm‐thick structure is described. The e‐beam lithography process was implemented with a careful evaluation of applied dosage, tests of different bake‐out temperatures and durations for the photoresist, and the use of a developer without methylisobutylketone. Electrodeposition with a pulsed current mode and with a specially designed apparatus produced the desired high‐aspect‐ratio nanostructures. The fabricated zone plates were examined by electron microscopy and their performances were assessed using a transmission X‐ray microscope. The results specifically demonstrated an image resolution of 40 nm. 相似文献