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991.
The expression of cecropin and lysozyme genes is induced in response to bacterial peptidoglycan in the fat body of the silkworm, Bombyx mori. Specific inhibitors of either phospholipase A2, cyclooxygenase or lipoxygenase significantly inhibit the induction of the immune genes both in vivo and in cultured fat body as detected by means of Northern hybridization. Arachidonic acid injected into the larvae induces the expression of the cecropin and lysozyme genes. The findings support the idea that eicosanoids mediate some process leading to the expression of immune genes in the fat body following recognition of peptidoglycan as a signal for invading bacteria. 相似文献
992.
Yoshi-Nori Nakamura Masashi Ando Manabu Seoka Ken-ichi Kawasaki Yasuyuki Tsukamasa 《Food chemistry》2007,103(1):234-241
Using the full-cycle cultured (FC) Pacific bluefin tuna, Thunnus orientalis [body weights: 13.1 ± 4.5 (FC1; April in 2004), 20.2 ± 1.8 (FC2; July in 2004), 28.5 ± 6.3 (FC3; November in 2004), 27.0 ± 3.3 (FC4; February in 2005) and 33.5 ± 4.7 kg (FC5; May in 2005), n = 3, respectively] and wild bluefin tuna [33.3 ± 1.5kg (June in 2005), n = 3], proximate and fatty acid compositions of the cephalal (Ce-) and caudal (Ca-) parts of the dorsal (D) and ventral (V) ordinary muscles (OMs) were investigated. Lipid contents of the Ce-DOM and VOMs of FC1-5 increased with growth. In particular, lipid content of the Ce-DOM (23.0%) and VOMs (55.1%) of FC5 was higher (P < 0.05) than those of wild tuna [D-(2.0%) and VOMs (16.2%)]. However, lipid contents of the Ca-DOM and VOMs of FC1-5 did not change with growth. On the other hand, the fatty acid compositions of the Ce-DOM and VOMs of FC2-5 resembled each other. However, there was no specific tendency of the changes of each fatty acid composition of the Ce-DOM of FC tuna with growth. On the other hand, total monounsaturated fatty acid content (30.1%) of the Ce-DOM of FC5 was higher (P < 0.05) than that (25.5%) of wild tuna. The ratio of n–3: n–6 (9.4%) of the Ce-VOM of FC5 was lower (P < 0.05) than that (14.0%) of wild tuna. However, the fatty acid compositions of the Ce-DOM and VOMs of FC tuna were not reflected by those of feed (whole fish bodies of sesame mackerel). 相似文献
993.
H Nagata K Ochiai Y Aotani K Ando M Yoshida I Takahashi T Tamaoki 《Canadian Metallurgical Quarterly》1997,50(7):537-542
In the course of screening for inhibitors of the lymphocyte kinase, Lck (p56lck), aiming at novel immunosuppressants, we isolated a novel alkaloid, lymphostin (LK6-A), from the culture broth of Streptomyces sp. KY11783. Lymphostin was produced in a fermentation medium supplemented with a highly porous polymer resin, which prevented the degradation of this compound in the culture broth. Lymphostin inhibited the kinase activity of Lck with an IC50 value of 0.05 microM, and exhibited potent inhibitory activity against the mixed lymphocyte reaction (MLR) with an IC50 value of 0.009 microM. 相似文献
994.
H Inufusa T Adachi M Suzuki O Ando T Ohta M Kurimoto Y Nakatani M Nakamura M Yasutomi 《Canadian Metallurgical Quarterly》1998,82(8):1563-1569
BACKGROUND: Tumor procoagulant is one of the factors responsible for disseminated intravascular coagulation and metastasis. The authors found procoagulant activity in LK52 human squamous cell carcinoma cells, which they designated cancer cell-derived blood coagulating activity 1 (CCA-1). A monoclonal antibody (MoAb) was generated to characterize this CCA-1 procoagulant activity. To date, antibodies that show an inhibitory effect on procoagulant activity as well as high reactivity in cancer cells are well known for their tissue factor specificity. METHODS: Characterization of the procoagulant activity of CCA-1 was performed and an anti-CCA-1 MoAb, FS01, was generated. CCA-1 expression on the cancer cell surface was examined by flow cytometry. Procoagulant activity of various cancer cell lines and the inhibitory effect of the FS01 MoAb on this procoagulant activity was monitored by a clot timer. RESULTS: The enzymologic character differed from that of cancer procoagulant (CP). The FS01 MoAb inhibited the procoagulant activity of CCA-1, but did not inhibit that of tissue factor. A positive correlation was observed between the expression intensity of CCA-1 and the inhibitory effect of the FS01 MoAb on the procoagulant activity of cancer cell lines. Expression of CCA-1 was observed more frequently than that of tissue factor in human cancer cell lines. CONCLUSIONS: The FS01 MoAb generated in the current study is a new antibody that reacts with various cancer cell lines, but not with normal cells. FS01 inhibits cancer cell-derived procoagulant activity and does not react with tissue factor and CP. CCA-1, which is recognized by the FS01 MoAb, appears to play a major role in cancer cell-derived procoagulant activity. 相似文献
995.
Hideo Kiyota Eiichi Matsushima Keisuke Sato Hideyo Okushi Toshihiro Ando Junzo Tanaka Mutsukazu Kamo Yoichiro Sato 《Diamond and Related Materials》1997,6(12):1753-1758
Relationship between growth condition and quality of homoepitaxially grown B-doped diamond (001) film has been studied using physical measurements of defect density as a function of doping concentration. In particular, electrical properties of the homoepitaxial diamond film were characterized using measurements of conductivity, carrier concentration and mobility. The highest mobility is found to be about 1000 cm2V−1s−1 at 293 K, indicating that the quality of the CVD diamond film is further improved through optimizing the growth condition. The density of the compensation donor was determined from the temperature-dependent hole concentration. The lowest donor density is found to be 8.4 × 1015 cm−3 in the present work. This is an order of magnitude greater than the lowest value measured in natural IIb diamond. Furthermore, it is also found that the donor density increases with increasing doping concentration during the growth. On the other hand, the mobility decreases rapidly with increasing doping concentration. From these results, we speculate that the compensation donor is an origin of an additional scattering center in diamond, and excessive B-doping makes the quality of the CVD diamond worse. 相似文献
996.
Tetsu Ando Kazuya Ohtani Masanobu Yamamoto Takashi Miyamoto Xu-Rong Qin Witjaksono 《Journal of chemical ecology》1997,23(10):2413-2423
The Japanese giant looper, Ascotis selenaria cretacea, is a serious defoliator of tea gardens in Japan. GC-MS analysis of the virgin female extract confirmed the presence of (Z,Z)-6,9-cis-3,4-epoxynonadecadiene. This compound had attracted male moths in a previous random screening test using C17–C23 epoxydienes synthesized in a racemic form. Further GC and HPLC analyses with chiral columns showed that the natural pheromone was composed of 3S,4R and 3R,4S isomers in a ratio of 53:47, although the field evaluation revealed stronger activity of the pure 3R,4S epoxide than of other enantiomeric mixtures. This result indicates that the sexual communication system of this Japanese subspecies differs from that of the species in Israel, which is selectively attracted to an isomer with the opposite configuration. Interestingly, the 3S,4R epoxide attracted another geometric male, Alcis angulifera, in our field tests. (Z,Z,Z)-3,6-9-Nonadecatriene, a parent olefinic compound of the epoxy pheromone, was also identified in the gland extract of A. s. cretacea, but its effect on the attractive activity of the epoxide was not assured in field tests. The amount of the triene increased in the virgin female during photophase and also after decapitation. The epoxy component completely disappeared after decapitation, but could be increased by an injection of subesophageal ganglion extract. The data suggest that the triene is a biosynthetic precursor of the epoxide and that a neuropeptide hormone (PBAN) regulates the epoxydation. 相似文献
997.
998.
Noriyuki Hirota Tsutomu Ando Ryo Tanaka Hitoshi Wada Yoshio Sakka 《Science and Technology of Advanced Materials》2009,10(1)
We studied methods of controlling the spacing between particles in the triangular lattice formed by feeble magnetic particles through induced magnetic dipole interaction. Formation of a triangular lattice is described by the balance between the magnetic force and the interaction of induced magnetic dipoles. The intensity of the magnetic force is proportional to the volume of particles V and the difference in the magnetic susceptibilities between the particles and the surrounding medium Δχ. On the other hand, the intensity of the induced magnetic dipole interaction depends on the square of V and Δχ. Therefore, altering the magnetic susceptibility difference by changing the susceptibility of the surrounding medium, volume of the particles, and intensity and spatial distribution of the applied magnetic field effectively controls the distance between the particles. In this study, these three methods were evaluated through experiment and molecular dynamics simulations. The distance between the particles, i.e. the lattice constant of the triangular lattice, was varied from 1.7 to 4.0 in units of the particle diameter. Formation of self-organized triangular lattice through the induced magnetic dipole interaction is based on magnetism, a physical property that all materials have. Therefore, this phenomenon is applicable to any materials of any size. Consequently, structure formation through induced magnetic dipole interaction is a potential way of fabricating materials with ordered structures. 相似文献
999.
The RFC5 gene encodes a small subunit of replication factor C (RFC) complex in Saccharomyces cerevisiae and has been shown to be required for the checkpoints which respond to replication block and DNA damage. Here we describe the isolation of RAD24, known to play a role in the DNA damage checkpoint, as a dosage-dependent suppressor of rfc5-1. RAD24 overexpression suppresses the sensitivity of rfc5-1 cells to DNA-damaging agents and the defect in DNA damage-induced Rad53 phosphorylation. Rad24, like Rfc5, is required for the regulation of Rad53 phosphorylation in response to DNA damage. The Rad24 protein, which is structurally related to the RFC subunits, interacts physically with RFC subunits Rfc2 and Rfc5 and cosediments with Rfc5. Although the rad24Delta mutation alone does not cause a defect in the replication block checkpoint, it does enhance the defect in rfc5-1 mutants. Furthermore, overexpression of RAD24 suppresses the rfc5-1 defect in the replication block checkpoint. Taken together, our results demonstrate a physical and functional interaction between Rad24 and Rfc5 in the checkpoint pathways. 相似文献
1000.
Pulmonary thromboendarterectomy was performed on two patients with chronic pulmonary thromboembolism showing thrombotic tendency. Patient 1 was a 25-year-old male with the disease complicated by congenital antithrombin III deficiency. Patient 2 was a 21-year-old male with the disease complicated by antiphospholipid syndrome. Both patients were admitted to the center upon showing dyspnea. Lung perfusion scintigraphy revealed multiple defects in the right and left lungs. Pulmonary arteriography showed occlusion and stenosis from lobar to segmental arteries. Cardiac catheterization showed marked pulmonary hypertension. Pulmonary angioscopy confirmed the presence of organized thrombi while an intravascular ultrasound revealed a thickening of the pulmonary arterial walls in both lungs. After the insertion of an inferior vena cava filter in each patient, surgery was performed. Following a median sternotomy, a cardiopulmonary bypass was utilized to induce deep hypothermia at a pharyngeal temperature of 16 degrees C, after which a thromboendarterectomy of the bilateral pulmonary arteries was performed under intermittent circulatory arrest. A large amount of organized thrombi was extracted from these arteries. After surgery, both patients showed good postoperative outcome with improved blood flow in both lungs, reduced pulmonary arterial pressure and increased cardiac output. 相似文献