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51.
Yuka Kurosaka Shuichi Machida Yoko Shiroya Hideki Yamauchi Kumiko Minato 《International journal of molecular sciences》2021,22(4)
Weight control based on dietary restriction (DR) alone can cause lipid metabolic failure and progression to fatty liver. This study aimed to investigate the effect of exercise on preventing DR-induced hepatic fat accumulation in Zucker fatty (ZF) rats by focusing on the relationship between adipose tissue lipolysis and hepatic fat uptake. Six-week-old male ZF rats were randomly assigned to obese, DR, or DR with exercise (DR + Ex) groups. The DR and DR + Ex groups were fed a restricted diet, with the latter also undergoing voluntary exercise. After 6 weeks, hepatic fat accumulation was observed in the DR group, whereas intrahepatic fat was markedly reduced in the DR + Ex group. Compared with the obese (Ob) group, the DR group exhibited 2.09-fold expression of hepatic fatty acid translocase (FAT)/CD36 proteins (p < 0.01) and 0.14-fold expression of hepatic fatty acid-binding protein (FABP)1 (p < 0.01). There were no significant differences between the DR + Ex group and the Ob group. FAT/CD36 and hepatic triglyceride (TG) expression levels were strongly positively correlated (r = 0.81, p < 0.001), whereas there was a strong negative correlation between FABP1 and hepatic TG expression levels (r = −0.65, p < 0.001). Our results suggest that hepatic fat accumulation induced by DR in ZF rats might be prevented through exercise-induced modifications in FAT/CD36 and FABP1 expression. 相似文献
52.
Isao Ishii Shotaro Kamata Saki Ito Aya Shimonaga Maika Koizumi Maiko Tsushima Asumi Miura Tomoko Nagata Yuka Tosaka Haruka Ohtani Waka Kamichatani Noriyuki Akahoshi 《International journal of molecular sciences》2022,23(2)
Methionine (Met) is considered the most toxic amino acid in mammals. Here, we investigated biochemical and behavioral impacts of ad libitum one-week feeding of high-Met diets on mice. Adult male mice were fed the standard rodent diet that contained 0.44% Met (1×) or a diet containing 16 graded Met doses (1.2×–13×). High-Met diets for one-week induced a dose-dependent decrease in body weight and an increase in serum Met levels with a 2.55 mM peak (versus basal 53 µM) on the 12×Met diet. Total homocysteine (Hcy) levels were also upregulated while concentrations of other amino acids were almost maintained in serum. Similarly, levels of Met and Hcy (but not the other amino acids) were highly elevated in the cerebrospinal fluids of mice on the 10×Met diet; the Met levels were much higher than Hcy and the others. In a series of behavioral tests, mice on the 10×Met diet displayed increased anxiety and decreased traveled distances in an open-field test, increased activity to escape from water soaking and tail hanging, and normal learning/memory activity in a Y-maze test, which were reflections of negative/positive symptoms and normal cognitive function, respectively. These results indicate that high-Met ad libitum feeding even for a week can induce bipolar disorder-like disease models in mice. 相似文献
53.
Amanda L. Scheiber Cierra A. Clark Takashi Kaito Masahiro Iwamoto Edwin M. Horwitz Yuka Imamura Kawasawa Satoru Otsuru 《International journal of molecular sciences》2022,23(3)
Extracellular vesicles (EVs) released by bone marrow stromal cells (BMSCs) have been shown to act as a transporter of bioactive molecules such as RNAs and proteins in the therapeutic actions of BMSCs in various diseases. Although EV therapy holds great promise to be a safer cell-free therapy overcoming issues related to cell therapy, manufacturing processes that offer scalable and reproducible EV production have not been established. Robust and scalable BMSC manufacturing methods have been shown to enhance EV production; however, the effects on EV quality remain less studied. Here, using human BMSCs isolated from nine healthy donors, we examined the effects of high-performance culture media that can rapidly expand BMSCs on EV production and quality in comparison with the conventional culture medium. We found significantly increased EV production from BMSCs cultured in the high-performance media without altering their multipotency and immunophenotypes. RNA sequencing revealed that RNA contents in EVs from high-performance media were significantly reduced with altered profiles of microRNA enriched in those related to cellular growth and proliferation in the pathway analysis. Given that pre-clinical studies at the laboratory scale often use the conventional medium, these findings could account for the discrepancy in outcomes between pre-clinical and clinical studies. Therefore, this study highlights the importance of selecting proper culture conditions for scalable and reproducible EV manufacturing. 相似文献
54.
Yuka Muranaka Asuka Mizutani Masato Kobayashi Koya Nakamoto Miki Matsue Kodai Nishi Kana Yamazaki Ryuichi Nishii Naoto Shikano Shigefumi Okamoto Keiichi Kawai 《International journal of molecular sciences》2022,23(5)
The effectiveness of L- and D-amino acids for detecting the early stage of infection in bacterial imaging was compared. We evaluated the accumulation of 3H-L-methionine (Met), 3H-D-Met, 3H-L-alanine (Ala), and 3H-D-Ala in E. coli EC-14 and HaCaT cells. Biological distribution was assessed in control and lung-infection-model mice with EC-14 using 3H-L- and D-Met, and 18F-FDG. A maximum accumulation of 3H-L- and D-Met, and 3H-L- and D-Ala occurred in the growth phase of EC-14 in vitro. The accumulation of 3H-L-Met and L-Ala was greater than that of 3H-D-Met and D-Ala in both EC-14 and HaCaT cells. For all radiotracers, the accumulation was greater in EC-14 than in HaCaT cells at early time points. The accumulation was identified at 5 min after injection in EC-14, whereas the accumulation gradually increased in HaCaT cells over time. There was little difference in biodistribution between 3H-L-and D-Met except in the brain. 3H-L- and D-Met were sensitive for detecting areas of infection after the spread of bacteria throughout the body, whereas 18F-FDG mainly detected primary infection areas. Therefore, 11C-L- and D-Met, radioisotopes that differ only in terms of 3H labeling, could be superior to 18F-FDG for detecting bacterial infection in lung-infection-model mice. 相似文献
55.
Harada Y Kobayashi M Niwa H Senba Y Ohashi H Tokushima T Horikawa Y Shin S Oshima M 《The Review of scientific instruments》2012,83(1):013116
An extremely high resolution flat field type slit less soft x-ray emission spectrometer has been designed and constructed for the long undulator beamline BL07LSU in SPring-8. By optimizing the ruling parameters of two cylindrical gratings, a high energy resolution ΔE < 100 meV and/or an E∕ΔE ~ 10 000 are expected for the energy range of 350 eV - 750 eV taking into account the broadening by the spatial resolution (25 μm) of a CCD detector. A coma-free operation mode proposed by Strocov et al., is also applied to eliminate both defocus and coma aberrations. The spectrometer demonstrated experimentally that E/ΔE = 10 050 and 8046 for N 1s (402.1 eV) and Mn 2p (641.8 eV) edges, respectively. 相似文献
56.
Hiromi Yoshida Megumi Tanaka Yuka Tomiyama Yoshiyuki Mizushina 《Journal of the American Oil Chemists' Society》2007,84(2):165-172
Extracted lipids from sesame (Sesamum indicum) seeds of three varieties were determined by high-performance liquid chromatography (HPLC) for endogenous antioxidants. The
molecular species and fatty acid (FA) distribution of triacylglycerol (TAG) isolated from total lipids in sesame seeds were
analyzed by a combination of argentation thin-layer chromatography (TLC) and gas chromatography (GC), and were investigated
in relation to their antioxidant distribution. γ-Tocopherol was present in highest concentration, and δ-, and α-tocopherols
were very small amounts. Sesamin and sesamolin were the main lignan components. A modified argentation-TLC procedure, developed
to optimize the separation of the complex mixture of total TAG, provided 12 different groups of TAG, based on both the degree
of unsaturation and the total acyl-chain length of FA groups. With a few exceptions, the major TAG components were SM2 (6.5–6.7%), SMD (19.8–20.7%), M2D (15.0–26.3%), MD2 (23.6–35.0%), and D3 (7.7–10.7%) (where S denotes a saturated FA, M denotes a monoene, D denotes a diene, and T denotes a triene). It seems that
the three varieties were highly related to each other based on the FA composition of the TAG as well as the distribution pattern
in the different TAG molecular species. These results suggest that there are no essential differences in the oil components
among the three varieties. 相似文献
57.
Hiromi Yoshida Yuka Tomiyama Naoko Yoshida Yoshiyuki Mizushina 《European Journal of Lipid Science and Technology》2009,111(4):386-391
Regiospecific distributions of fatty acids of triacylglycerols (TAG) and phospholipids (PL) separated from broad beans (Vicia faba) of four cultivars (Minpo, Sanuki, Nintoku and Sanren) were investigated. The major lipid components were PL (47.5–50.5 wt‐%) and TAG (47.7–50.1 wt‐%), while steryl esters, hydrocarbons, free fatty acids, diacylglycerols and monoacylglycerols were present in minor proportions (1.6–2.4 wt‐%). The PL components isolated from the four cultivars were phosphatidylcholine (56.4–58.4 wt‐%), phosphatidylethanolamine (20.3–21.7 wt‐%) and phosphatidylinositol (16.6–18.6 wt‐%). Phosphatidylinositol was unique in that it had the highest saturated fatty acid content among these PL. The principal characteristics of the fatty acid distribution in the TAG and PL were evident in the beans: Unsaturated fatty acids were predominantly concentrated in the sn‐2 position while saturated fatty acids primarily occupied the sn‐1 or sn‐3 position in these lipids. The lipid components and fatty acid distributions were almost the same in the four cultivars and were not influenced by genetic variability and planting location. These results could be useful information to both consumers and producers for the manufacture of traditional broad bean foods in Japan. 相似文献
58.
Methyl 3‐Hydroxymyristate,a Diffusible Signal Mediating phc Quorum Sensing in Ralstonia solanacearum
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Prof. Kenji Kai Hideyuki Ohnishi Mika Shimatani Shiho Ishikawa Yuka Mori Prof. Akinori Kiba Prof. Kouhei Ohnishi Prof. Mitsuaki Tabuchi Prof. Yasufumi Hikichi 《Chembiochem : a European journal of chemical biology》2015,16(16):2309-2318
Ralstonia solanacearum, a plant pathogenic bacterium causing “bacterial wilt” on crops, uses a quorum sensing (QS) system consisting of phc regulatory elements to control its virulence. Methyl 3‐hydroxypalmitate (3‐OH PAME) was previously identified as the QS signal in strain AW1. However, 3‐OH PAME has not been reportedly detected from any other strains, and this suggests that they produce another unknown QS signal. Here we identify (R)‐methyl 3‐hydroxymyristate [(R)‐3‐OH MAME] as a new QS signal that regulates the production of virulence factors and secondary metabolites. (R)‐3‐OH MAME was synthesized by the methyltransferase PhcB and sensed by the histidine kinase PhcS. The phylogenetic trees of these proteins from R. solanacearum strains were divided into two groups, according to their QS signal types—(R)‐3‐OH MAME or (R)‐3‐OH PAME. These results demonstrate that (R)‐3‐OH MAME is another crucial QS signal and highlight the unique evolution of QS systems in R. solanacearum. 相似文献
59.
Micro-flocs of NOM coagulated by polyaluminium chloride (PACl), alum and polysilicate-iron (PSI) were characterized by flocs size, HPSEC-based molecular weight and the captured content of coagulants-based aluminium and iron. Changes in floc composition with respect to the mass ratios of captured NOM to Al and Fe were examined. Lowering water pH to optimum levels was found to be capable of removing small NOM constituents that are generally difficult to be precipitated at neutral pH levels. For PACl and PSI, the distribution of micro flocs (0.1-5.0 microm) reached steady stage after rapid mixing for 30 seconds, with NOM being found existent within the non-coagulated fraction (d<0.1 microm) and the coagulated fraction with floc sizes above 5.0 microm (d >5.0 microm). For alum, however, the existence of NOM inside intermediate floc fractions of d = 0.1-1.0 microm, 1.0-3.0microm and 3.0-5.0 microm was confirmed. 相似文献
60.
To manufacture low noise and high output tape, we have to choose excellent particles and also make its surface as smooth as possible. We developed a metal tape with higher output and higher S/N compared with those of conventional oxide tape by introducing new technologies of higher packing density and mirror surface finishing. This metal tape realized higher recording density which could be used in 8 mm Video, electronic still camera ("MAVICA"), magnetic contact printing system and various digital recording systems. This paper describes characteristics and applications of the metal tape. 相似文献