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101.
Serum hyaluronan measurement is an option for diagnosing cirrhosis and assessing liver fibrosis, but it is of little use in the diagnosis of chronic hepatitis and compensated liver cirrhosis. It is generally known that intake of food results in elevation of the serum hyaluronan concentration. This work was designed to determine whether a change in the serum hyaluronan concentration after eating might reflect the hepatic sinusoidal endothelial cell impairment in chronic liver diseases. The chronological measurement of serum hyaluronan concentration after eating was performed after an overnight fast in 31 patients with chronic hepatitis, 31 cirrhotic patients, and 8 healthy subjects. The hyaluronan concentration in the loading test increased with the severity of the liver disease in the patients with chronic hepatitis, being significantly higher in the patients with moderate or a higher grade of necroinflammation than in those with a minimal grade, and also significantly higher in patients with stage 3 fibrosis than in those with stage 2 or less. The elevation of the concentration after eating in patients with liver cirrhosis was marked and the range did not overlap with that in patients with chronic hepatitis. Even in 14 patients with compensated liver cirrhosis whose hyaluronan concentration pre-prandially was less than 200 ng/ml, the range of the post-prandial peak concentration did not overlap with that in the chronic hepatitis patients. These results suggest that the evaluation of post-prandial serum hyaluronan concentration is potentially useful for assessing the grading of necroinflammation and staging of fibrosis in patients with chronic hepatitis, as well as for diagnosing compensated liver cirrhosis. 相似文献
102.
Ogawa K. Kurata M. Suzuki H. Osawa S. Kato H. Ichiyanagi N. Kawasaki K. 《Power Delivery, IEEE Transactions on》1989,4(1):50-57
The development of 275 kV internally-conductor-cooled cable systems is under way for application to long-distance large-capacity (1500 MVA/cct) underground transmission systems. From the viewpoint of the reliability and the energy economy of these systems, the operational control system for the cooling facilities is especially important, because the facilities require large cooling capacity due to the large heat loss of the cable conductor. The cooling device characteristics are described, and the effects of operation control on energy savings are examined. A long-term field test has shown that the computer-controlled operation system is very useful. Simulation results for the operational control system confirm that calculated values are in good agreement with measurement results 相似文献
103.
An organic–inorganic hybrid material was prepared from a pentacyclo[9.5.1.13,9.15,15.17,13]octasiloxane bearing eight coumarin groups. The coumarin groups were photodimerized by UV‐light irradiation to connect the monomer units of the octasiloxane. Using a concentrated solution, the intermolecular photodimerization of these coumarin groups leaded to the cross‐linking of the octasiloxane, fabricating an organic–inorganic hybrid material with a three‐dimensional nanostructure. Whereas in dilute solution the intramolecular photodimerization was preferred to the intermolecular reaction, resulting in no formation of polymeric material. 相似文献
104.
105.
R. Takahashi Y. Yonezawa M. Ohtani M. Kawasaki K. Nakajima T. Chikyow H. Koinuma Y. Matsumoto 《Advanced functional materials》2006,16(4):485-491
Excellent crystallinity of material films and atomic control of their surface/interface, sufficient for the realization of their optimal physical properties, are technological premises for modern functional‐device applications. Bi4Ti3O12 and related compounds attract much interest as highly insulating, ferroelectric materials for use in ferroelectric random‐access memories. However, it has been difficult thus far for Bi4Ti3O12 films to satisfy such requirements when formed using vapor‐phase epitaxy, owing to the high volatility of Bi in a vacuum. Here, we demonstrate that flux‐mediated epitaxy is one of the most promising and widely applicable concepts to overcome this inevitable problem. The key point of this process is the appropriate selection of a multi‐component flux system. A combinatorial approach has led to the successful discovery of the novel flux composition of Bi–Cu–O for Bi4Ti3O12 single‐crystal film growth. The perfect single‐crystal nature of the stoichiometric Bi4Ti3O12 film formed has been verified through its giant grain size and electric properties, equivalent to those of bulk single crystals. This demonstration has broad implications, opening up the possibility of preparing stoichiometric single‐crystal oxide films via vapor‐phase epitaxy, even if volatile constituents are required. 相似文献
106.
107.
M Iitaka S Miura K Yamanaka S Kawasaki S Kitahama Y Kawakami S Kakinuma I Oosuga S Wada S Katayama 《Canadian Metallurgical Quarterly》1998,83(11):3908-3912
Vascular endothelial growth factor (VEGF) is one of the angiogenic factors. We examined both thyroid volume and intrathyroidal vascular area by color flow Doppler ultrasonography in patients with Graves' disease (GD), Hashimoto's thyroiditis (HT), and subacute thyroiditis. The serum concentrations of thyroid hormones, TSH, TSH receptor antibodies, and VEGF were also examined. There was a significant increase in serum VEGF levels in patients with untreated GD and goitrous HT compared with those in healthy subjects. The serum VEGF levels in untreated patients with subacute thyroiditis were significantly higher than those in patients with untreated GD or HT. There was a significant correlation between serum VEGF levels and the ratio of intrathyroidal vascular area and thyroid area in untreated patients with GD who had a goiter larger than or equal to 40 cm3. There was also a significant correlation between serum VEGF and TSH levels in patients with HT who were hypothyroid and had a goiter. Serum VEGF levels decreased significantly in these patients after treatment; this was accompanied by a significant decrease in intrathyroidal vascular area and thyroid volume. Our study demonstrates that VEGF appears to play an important role in intrathyroidal angiogenesis in patients with GD and goitrous HT. 相似文献
108.
E Simone D Daniel N Schloot P Gottlieb S Babu E Kawasaki D Wegmann GS Eisenbarth 《Canadian Metallurgical Quarterly》1997,94(6):2518-2521
Restricted use of T cell receptor (TCR) gene segments is characteristic of several induced autoimmune disease models. TCR sequences have previously been unavailable for pathogenic T cells which react with a defined autoantigen in a spontaneous autoimmune disease. The majority of T cell clones, derived from islets of NOD mice which spontaneously develop type I diabetes, react with insulin peptide B-(9-23). We have sequenced the alpha and beta chains of TCRs from these B-(9-23)-reactive T cell clones. No TCR beta chain restriction was found. In contrast, the clones (10 of 13) used V alpha13 coupled with one of two homologous J alpha segments (J alpha45 or J alpha34 in 8 of 13 clones). Furthermore, 9 of 10 of the V alpha13 segments are a novel NOD sequence that we have tentatively termed V alpha13.3. This dramatic alpha chain restriction, similar to the beta chain restriction of other autoimmune models, provides a target for diagnostics and immunomodulatory therapy. 相似文献
109.
Repeated temperature modulation epitaxy for p-type doping and light-emitting diode based on ZnO. 总被引:27,自引:0,他引:27
Atsushi Tsukazaki Akira Ohtomo Takeyoshi Onuma Makoto Ohtani Takayuki Makino Masatomo Sumiya Keita Ohtani Shigefusa F Chichibu Syunrou Fuke Yusaburou Segawa Hideo Ohno Hideomi Koinuma Masashi Kawasaki 《Nature materials》2005,4(1):42-46
Since the successful demonstration of a blue light-emitting diode (LED), potential materials for making short-wavelength LEDs and diode lasers have been attracting increasing interest as the demands for display, illumination and information storage grow. Zinc oxide has substantial advantages including large exciton binding energy, as demonstrated by efficient excitonic lasing on optical excitation. Several groups have postulated the use of p-type ZnO doped with nitrogen, arsenic or phosphorus, and even p-n junctions. However, the choice of dopant and growth technique remains controversial and the reliability of p-type ZnO is still under debate. If ZnO is ever to produce long-lasting and robust devices, the quality of epitaxial layers has to be improved as has been the protocol in other compound semiconductors. Here we report high-quality undoped films with electron mobility exceeding that in the bulk. We have used a new technique to fabricate p-type ZnO reproducibly. Violet electroluminescence from homostructural p-i-n junctions is demonstrated at room-temperature. 相似文献
110.
The nucleotide sequence of the gene encoding an endo-1,5-alpha-L-arabinase (protopectinase C) of Bacillus subtilis was determined by sequencing fragments amplified by the cassette-ligation-mediated PCR (CLM-PCR). The gene covering the start and stop codon was amplified by PCR with two specific primers, which were designed from the sequence data determined by CLM-PCR. An approximately 1.5-kb amplification product was cloned into the vector pUC119, forming a plasmid termed pPPC. An ORF that encodes the arabinase composed of 324 amino acids including a 33-amino-acid signal peptide was assigned. Comparison of the deduced amino acid sequence of the enzyme with that of an Aspergillus niger endoarabinase showed 37% identity in a 207-amino-acid overlap. The optimal nucleotide sequence for catabolite repression of B. subtilis was found upstream of the structural gene. In a culture of Escherichia coli DH5alpha cells harboring pPPC, no arabinase activity was detected, either intracellularly or extracellularly, suggesting that the B. subtilis promotor is not functional in this transformant. In B. subtilis IFO 3134 strain, production of protopectinase C was repressed by readily metabolizable carbohydrates. In contrast, productivity (total enzyme activity/bacterial growth) of the enzyme was increased about fourfold in the presence of 0.75 M potassium phosphate in the culture medium. The phosphate anion seemed to be involved in the stimulation of protopectinase C production in this stain. 相似文献