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排序方式: 共有383条查询结果,搜索用时 15 毫秒
11.
Catarine Massucato Nishijima Flavia Karina Delella Clenilson Martins Rodrigues Daniel Rinaldo Monica Valdyrce dos Anjos Lopes-Ferreira Lucia Regina Machado da Rocha Wagner Vilegas Sergio Luis Felisbino Clélia Akiko Hiruma-Lima 《International journal of molecular sciences》2015,16(6):12454-12466
Inflammation and haemorrhage are the main characteristics of tissue injury in botropic envenomation. Although some studies have shown that anti-venom prevents systemic reactions, it is not efficient in preventing tissue injury at the site of the bite. Therefore, this work was undertaken to investigate the anti-inflammatory effects of the methanolic extract and fractions from D. elliptica and to evaluate the role of matrix metalloproteinases (MMPs) in this process. Effects of the extract and fractions from D. elliptica were evaluated using a carrageenan-induced paw oedema model in rats, and leukocyte rolling was visualized by intravital. The quantification of MMPs activities (MMP-2 and MMP-9) extracted from the dermis of mice treated with extract and fractions alone or incubated with venom was determined by zymographic analyses. Our results show that intraperitoneal (i.p.) injection of fractions significantly reduced paw oedema after the carrageenan challenge. Treatment with the tannins fraction also resulted in considerable inhibition of the rolling of leukocytes and this fraction was able to decrease the activation of MMP-9. These results confirmed the anti-inflammatory activity of the methanolic extract and tannins fraction of D. elliptica and showed that the dermonecrosis properties of B. jararaca venom might be mediated through the inhibition of MMP-9 activity. 相似文献
12.
Automated Synthesis of (rac)‐, (R)‐, and (S)‐[18F]Epifluorohydrin and Their Application for Developing PET Radiotracers Containing a 3‐[18F]Fluoro‐2‐hydroxypropyl Moiety 下载免费PDF全文
Dr. Tomoteru Yamasaki Yiding Zhang Wakana Mori Dr. Masayuki Hanyu Katsushi Kumata Akiko Hatori Dr. Lin Xie Nobuki Nengaki Prof. Dr. Ming‐Rong Zhang 《ChemMedChem》2018,13(16):1723-1731
To introduce the 3‐[18F]fluoro‐2‐hydroxypropyl moiety into positron emission tomography (PET) radiotracers, we performed automated synthesis of (rac)‐, (R)‐, and (S)‐[18F]epifluorohydrin ([18F] 1 ) by nucleophilic displacement of (rac)‐, (R)‐, or (S)‐glycidyl tosylate with 18F? and purification by distillation. The ring‐opening reaction of (R)‐ or (S)‐[18F] 1 with phenol precursors gave enantioenriched [18F]fluoroalkylated products without racemisation. We then synthesised (rac)‐, (R)‐, and (S)‐ 2‐{5‐[4‐(3‐[18F]fluoro‐2‐hydroxypropoxy)phenyl]‐2‐oxobenzo[d]oxazol‐3(2H)‐yl}‐N‐methyl‐N‐phenylacetamide ([18F] 6 ) as novel radiotracers for the PET imaging of translocator protein (18 kDa) and showed that (R)‐ and (S)‐[18F] 6 had different radioactivity uptake in mouse bone and liver. Thus, (rac)‐, (R)‐, and (S)‐[18F] 1 are effective radiolabelling reagents and can be used to develop PET radiotracers by examining the effects of chirality on their in vitro binding affinities and in vivo behaviour. 相似文献
13.
Masanori Yamazaki Akiko Nishijima Kazuko Ikeda Shoji Ichihara 《Polymer Bulletin》2004,52(3-4):267-274
Summary
In order to obtain materials with nanopores which will be applicable for many fields, the structures of the cured blends of phenolic resin (PhN), poly(methyl methacrylate) (PMMA) and curing agent were studied. After PMMA was extracted from cured blends, the structures of cured phenolic resins were observed with SEM. As a results, it was found that nanosized continuous pore structures were formed in extremely wide composition region if curing temperature was high. 相似文献
14.
Production of eicosapentaenoic acid by a recombinant marine cyanobacterium, Synechococcus sp. 总被引:1,自引:0,他引:1
The eicosapentaenoic acid (EPA) synthesis gene cluster from an EPA-producing bacterium, Shewanella sp. SCRC-2738, was cloned into a broad-host range vector, pJRD215, and then introduced into a marine cyanobacterium, Synechococcus sp. NKBG15041c, by conjugation. The transconjugant cyanobacteria produced 3.7±0.2% (2.24±0.13 mg/L) EPA (n-3) and 2.5 ±0.2%
(1.49±0.06 mg/L) eicosatetraenoic acid (n-3) of the total fatty acids when the cells were cultured at 23°C at a light intensity
of 1,000–1,500 Lux. The EPA and eico-satetraenoic acid contents of the cells were increased to 4.6±0.6% (3.86±1.11 mg/L) and
4.7±0.3% (3.86±0.82 mg/L), and 7.5±0.3% (1.76±0.10 mg/L) and 5.1±0.2% (1.19±0.06 mg/L) when they were cultured at low temperature
(18°C) and at lower light intensity (40 Lux), respectively. 相似文献
15.
Gotoh N Noguchi Y Ishihara A Yamaguchi K Mizobe H Nagai T Otake I Ichioka K Wada S 《Journal of oleo science》2010,59(12):631-639
Now it is recognized that DHA is oxidatively stable fatty acid compared with linoleic acid (LA) in emulsified system, although DHA is oxidatively unstable in a bulk system. In fact, an emulsified mixture of DHA and LA behaves as in a bulk system, namely the oxidative stability of DHA becomes lower than that of LA. Therefore, in this study, tridocosahexaenoate (DDD) and glycerol trilinoleate (LLL) were separately emulsified using TritonX-100 as an emulsifier and DDD emulsion was mixed with the oxidizing LLL emulsion using a water-soluble radical initiator, 2,2'-azobis(2-aminopropane) dihydrochloride. As a result, DHA suppressed the oxidation of LA, while DHA was not significantly oxidized. This suppression ability was examined using glycerol trieicosapentaenoate, glycerol trilinolenate, or glycerol trioleate instead of DDD and it was found that this activity was increased with the increasing number of double bonds in the structure. Furthermore, the same type of experiment was carried out using a lipid-soluble radical initiator, 2,2'-azobisisobutyronitrile and the similar result was obtained. These results indicated that a highly polyunsaturated fatty acid might act as an antioxidant in an emulsion system oxidized by an azo compound. 相似文献
16.
Tetsuya OGAWA Hideki ISHIDA Nami MATSUDA Ayuko FUJIU Akiko MATSUDA Kyoko ITO Yoshitaka ANDO Kosaku NITTA 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(3):301-306
Vascular calcification is associated with a poor prognosis in dialysis patients. It can be assessed with computed tomography but simple inoffice techniques may provide useful information. We compared the results obtained with a simple noninvasive technique with those obtained using multidetector computed tomography for aortic arch calcification volume (AoACV) in chronic hemodialysis (HD) patients. The enrolled study subjects were 63 (32 men and 31 women) maintenance HD patients. Calcification of the aortic arch was semiquantitatively estimated with a AoAC score (AoACS) on plain chest radiology. The AoACV was increased, with a mean value of 6.6 ranging from 0% to 36.5%. The coefficient of intraobserver variation was less than 2.5%. Aortic arch calcification score was highly correlated with AoACV (r=0.635, P<0.001). Multiple regression analysis showed age (F value=12.62, P<0.001) and pulse pressure (F value=4.54, P=0.037) to be significant independent determinants of AoACS. In conclusion, a simple measurement of AoACS may be useful for inoffice imaging to choose a therapeutic regimen in HD patients. 相似文献
17.
Akiko Yamamoto Sachiko Hiromoto 《Materials science & engineering. C, Materials for biological applications》2009,29(5):1559-1568
The possibility of magnesium and its alloys in medical applications is actively investigated in these days for the realization of biodegradable metallic devices. However, the degradation behavior and mechanisms of magnesium and its alloys in physiological environment such as inside the human body have not been elucidated. In this study, we performed 14-d long immersion tests of pure magnesium (3N) in 4 kinds of physiological solutions simulating the body fluids to examine the effects of the chemical components of the body fluids on the degradation of magnesium. The degradation rate of pure magnesium was strongly influenced by the kinds of the solution used. The highest degradation rate was obtained in NaCl, followed by E-MEM, Earle's solution, and E-MEM+FBS. The average degradation rate in NaCl for 8–14 d is about 100 times larger than that in E-MEM+FBS, which is the closest solution to human blood plasma. These results show that protein adsorption and insoluble salt formation retarded magnesium degradation, whereas organic compounds such as amino acids encourage the dissolution of magnesium. Buffering the solution also influenced the degradation rate; buffering NaCl with HEPES increased the degradation rate but buffering with NaHCO3 decreased it. Based on these results, the use of appropriate solution such as E-MEM+FBS is important for in vitro evaluation of the magnesium degradation rate under the physiological environment simulating inside the human body. 相似文献
18.
Hideki Tanaka Daisuke Noguchi Akiko Yuzawa Tetsuya Kodaira Hirofumi Kanoh Katsumi Kaneko 《Journal of Low Temperature Physics》2009,157(3-4):352-373
We have investigated the applicability of simulations and theoretical techniques for exploring the selectivities of hydrogen isotopes. We have simulated the adsorption isotherms of H2 in an idealized carbon slit pore at 77 K by using the grand canonical Monte Carlo simulations with the Feynman-Hibbs effective potential (FH-GCMC) and the rigorous path integral method (PI-GCMC), and we obtained good agreement between the isotherms from both simulations. This suggests that FH-GCMC, which uses the approximative Feynman-Hibbs treatment, is as useful as PI-GCMC for exploring H2 adsorption at 77 K. Moreover, we show that the ideal adsorption solution theory (IAST) can predict the selectivity of D2 over H2 in the interstices of single-wall carbon nanotube (SWNT) bundles at 77 K (below 0.1 MPa) very well by comparing the obtained results with the mixture adsorption FH-GCMC simulations. This indicates that IAST is also applicable to the estimation of the selectivity of D2 over H2 at moderate pressures and at 77 K from experimental single-component adsorption isotherms. We also demonstrate that the FH-GCMC simulation can reproduce the experimental adsorption isotherms of H2 and D2 in aluminophosphate AlPO4-5 at 77 K. Finally, we analyze the selectivity of D2 over H2 by IAST with the experimental single-component adsorption isotherms of H2 and D2 at 77 K for a variety of adsorbents: AlPO4-5, activated carbon fibers (ACFs), HiPco SWNT, and SWNHs. The selectivities predicted by the experimental adsorption data based on the results from the FH-GCMC simulations are presented and discussed. 相似文献
19.
20.
A novel optical sensor based on spectroscopic measurement of the plasmon absorption of a colloidal gold submonolayer immobilized upon a planar waveguide has been developed for label-free detection of biomolecular interactions at the sensor's surface. We fabricated the sensor by locally modifying a 50-microm-thick glass plate with hemoglobin (Hb) and then self-assembling gold colloids from the aqueous solution onto the Hb-modified area of the glass plate. Polychromatic light from a xenon-arc lamp was launched into the thin-film glass plate by use of a broadband fiber-coupling method. With the use of a CCD detector to monitor the light beam emitted from an end face of the glass plate, the plasmon absorption spectrum of the colloidal gold submonolayer was determined to depend on the polarization states of the guided light and to change with the refractive index of the medium in contact with the colloids. In addition to simplicity of fabrication and the ease of use, the sensor yields a larger absorbance sensitivity than the normal transmission measurement. 相似文献