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441.
Skeletal muscle regeneration is a well-organized process that requires remodeling of the extracellular matrix (ECM). In this study, we revealed the protective role of periostin, a matricellular protein that binds to several ECM proteins during muscle regeneration. In intact muscle, periostin was localized at the neuromuscular junction, muscle spindle, and myotendinous junction, which are connection sites between muscle fibers and nerves or tendons. During muscle regeneration, periostin exhibited robustly increased expression and localization at the interstitial space. Periostin-null mice showed decreased muscle weight due to the loss of muscle fibers during repeated muscle regeneration. Cultured muscle progenitor cells from periostin-null mice showed no deficiencies in their proliferation, differentiation, and the expression of Pax7, MyoD, and myogenin, suggesting that the loss of muscle fibers in periostin-null mice was not due to the impaired function of muscle stem/progenitor cells. Periostin-null mice displayed a decreased number of CD31-positive blood vessels during muscle regeneration, suggesting that the decreased nutritional supply from blood vessels was the cause of muscle fiber loss in periostin-null mice. These results highlight the novel role of periostin in maintaining muscle mass during muscle regeneration.  相似文献   
442.
Cabbage is one of the most widely grown, traded and consumed vegetables in the world. Therefore, it is vital to maintain cabbage quality after harvest; it is especially critical to counteract water loss in order to maintain quality during storage. In this study, we investigated the effect of a bag-in-box packaging on water loss in cabbages during 15 days of storage at 10°C and 90% relative humidity. The bag-in-box packaging included a low-density polyethylene bag along with a corrugated board box, whereas the control comprised a corrugated board box without any waterproofing ability. The changes in green colour, soluble solids content and ascorbic acid content of cabbage were evaluated as fundamental qualities. After storage, water loss from control samples was evaluated to be 6%; however, the bag-in-box packaging reduced the water loss to 0.3%. Moreover, the bag-in-box did not affect the tested fundamental qualities despite a delay in the cooling process. In conclusion, the bag-in-box packaging could be effective at maintaining the quality of cabbages and other leafy vegetables during storage and distribution for 15 days.  相似文献   
443.
Y257 of Oryza sativa parkeol synthase (OsOSC2) corresponds to H234 of Saccharomyces cerevisiae lanosterol cyclase (ScLAS), which is believed to be responsible for the final deprotonation reaction. An Ala mutant afforded nine tetracyclic skeletons as the main products; they consisted of protostadien ol scaffolds with both 17R and 17S configurations and both 20R and 20S configurations, as well as a pair of 20R- and 20S-configured parkeols. The production of 20R- and 20S-configured tetracycles (59:40 ratio) through the action of the Y257A mutant indicated that the substrate folding had been altered from a chair–boat–chair–chair (a normal folding pattern) to a chair–boat–chair–boat structure (an unusual folding pattern). Other mutants with different steric bulks also yielded both 20R- and 20S-configured tetracycles. Thus, the primary function of Y257 appears to be to impose a normal chair structure at the D-ring site through having appropriate steric bulk. In contrast, mutations at H234 of ScLAS were reported to cause no conformational changes. The OsOSC2 Phe mutant also yielded 20R- and 20S-configured parkeols (25:33 ratio), thus suggesting that the OH group of Y257 can form hydrogen bonds with other amino acids to force a chair conformation at the D-ring site, and this variant also gave 20R- and 20S-configured parkeols in a high yield (60 %). Y257 is unlikely to act as a base to abstract H-11 and stabilize the transient cation through cation–π interactions. Thus, the catalytic roles of Y257 are significantly different from those of H234 of ScLAS.  相似文献   
444.
Dinotefuran is an insecticide belonging to the neonicotinoid class, which is frequently used to control pests in paddy rice owing to its permeability and effectiveness against sucking insects. Since 2002, this insecticide has been commercially available in Japan, and has become controversial due to its high detection frequency in brown rice for primary consumption. In this study, the effects of processing and cooking on the reduction of dinotefuran residues in commercially available brown rice were investigated. Boiled rice is difficult to homogenise and extract with acetonitrile. Using pre-freezing and cryogenic milling with powdered dry ice, dinotefuran in boiled rice was extracted well. A measurement method comprising sample preparation (acetonitrile extraction, gel permeation chromatography, and SPE) and detection with anLC–MS/MS system was used. In 10 out of 25 commercial brown rice samples, dinotefuran was detected at a concentration of 0.04 μg/g (mean), which was more than the limit of quantitation of 0.01 μg/g. The dinotefuran levels were significantly less than the MRL of 2 μg/g in Japan. Even after polishing, washing, and boiling, dinotefuran was detected in 10 brown rice samples, with mean residue levels of 74.7%, 60.8%, and 39.6%, respectively, of the original concentration in brown rice. Based on these data, the processing factor of dinotefuran in boiled rice has been estimated to be approximately 0.4. Dinotefuran residues were reduced in the boiled rice, but less so than other pesticides. Although the maximum daily intake of dinotefuran in boiled rice was 0.0065 mg/person/day, its percent ratio to the ADI of dinotefuran in Japan was less than 0.05%. These results suggest that the daily intake of dinotefuran from rice might not be a critical problem at present, in spite of its relatively high detection frequency in boiled rice.  相似文献   
445.
General odorant-binding proteins (GOBPs) of moths are postulated to be involved in the reception of semiochemicals other than sex pheromones, the so-called “general odorants.” We have expressed two GOBPs, AtraGOBP1 and AtraGOBP2, which were previously isolated from the antennae of the navel orangeworm, Amyelois transitella. Surprisingly, these two proteins did not bind compounds that are known to attract adult moths, particularly females. The proper folding and functionality of the recombinant proteins was inferred from circular dichroism analysis and demonstration that both GOBPs bound nonanal in a pH-dependent manner. EAG experiments demonstrated that female attractants (1-phenylethanol, propionic acid phenyl ester, and isobutyric acid phenyl ester) are detected with high sensitivity by the antennae of day-0 to day-4 adult females, with response declining in older moths. The same age-dependence was shown for male antennae responding to constituents of the sex pheromone. Interestingly, AtraGOBP2 bound the major constituent of the sex pheromone, Z11Z13-16Ald, with affinity comparable to that shown by a pheromone-binding protein, AtraPBP1. The related alcohol bound to AtraPBP1 with higher affinity than to AtraGOBP2. AtraGOBP1 bound both ligands with low but nearly the same affinity.  相似文献   
446.
Adrenoleukodystrophy (X-ALD) is an X-linked genetic disorder caused by mutation of the ATP-binding cassette subfamily D member 1 gene, which encodes the peroxisomal membrane protein, adrenoleukodystrophy protein (ALDP). ALDP is associated with the transport of very-long-chain fatty acids (VLCFAs; carbon chain length ≥ 24) into peroxisomes. Defective ALDP leads to the accumulation of saturated VLCFAs in plasma and tissues, which results in damage to myelin and the adrenal glands. Here, we profiled the glycosphingolipid (GSL) species in fibroblasts from X-ALD patients. Quantitative analysis was performed using liquid chromatography–electrospray ionization–tandem mass spectrometry with a chiral column in multiple reaction monitoring (MRM) mode. MRM transitions were designed to scan for precursor ions of long-chain bases to detect GSLs, neutral loss of hexose to detect hexosylceramide (HexCer), and precursor ions of phosphorylcholine to detect sphingomyelin (SM). Our results reveal that levels of C25 and C26-containing HexCer, Hex2Cer, NeuAc-Hex2Cer, NeuAc-HexNAc-Hex2Cer, Hex3Cer, HexNAc-Hex3Cer, and SM were elevated in fibroblasts from X-ALD patients. In conclusion, we precisely quantified SM and various GSLs in fibroblasts from X-ALD patients and determined structural information of the elevated VLCFA-containing GSLs.  相似文献   
447.
Comparative analysis was performed with a CFo ATP synthase subunit II homologue (CFo-II) derived from marine or fresh-water algae. The marine algae-derived CFo-II-transformed Escherichia coli grew and accumulated ATP more vigorously in NaCl or Cadmium containing medium, suggesting that this gene was useful for the development of stress-tolerant plant.  相似文献   
448.
449.
Fong  Kenneth N. K.  Tang  Yuk Ming  Sie  Karen  Yu  Andy K. H.  Lo  Cherry C. W.  Ma  Yuko W. T. 《Virtual Reality》2022,26(2):453-464
Virtual Reality - Task-specific training has been proven to be effective in promoting recovery of the hemiparetic upper extremities after a stroke. This study was to develop a task-specific VR...  相似文献   
450.
Owing to progress in perinatal medicine, the survival of preterm newborns has markedly increased. However, the incidence of cerebral palsy has risen in association with increased preterm birth. Cerebral palsy is largely caused by cerebral hypoxic ischemia (HI), for which there are no effective medical treatments. We evaluated the effects of stromal cell-derived factor-1α (SDF-1α) on neonatal brain damage in rats. Left common carotid (LCC) arteries of seven-day-old Wistar rat pups were ligated, and animals were exposed to hypoxic gas to cause cerebral HI. Behavioral tests revealed that the memory and spatial perception abilities were disturbed in HI animals, and that SDF-1α treatment improved these cognitive functions. Motor coordination was also impaired after HI but was unimproved by SDF-1α treatment. SDF-1α reduced intracranial inflammation and induced cerebral remyelination, as indicated by the immunohistochemistry results. These data suggest that SDF-1α specifically influences spatial perception abilities in neonatal HI encephalopathy.  相似文献   
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