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91.
Shinsuke Kajioka Naoki Wakamiya Hiroki Satoh Kazuya Monden Masato Hayashi Susumu Matsui Masayuki Murata 《Ad hoc Networks》2011,9(5):911-927
To accommodate real-time multimedia application while satisfying application QoS requirements in a wireless ad-hoc network, we need QoS control mechanisms. In this paper, we propose a new routing mechanism to support real-time multimedia communication by efficiently utilize the limited wireless network capacity. Our mechanism considers a wireless ad-hoc network composed of nodes equipped with multiple network interfaces to each of which a different wireless channel can be assigned. By embedding information about channel usage in control messages of OLSRv2, each node obtains a view of topology and bandwidth information of the whole network. Based on the obtained information, a source node determines a logical path with the maximum available bandwidth to satisfy application QoS requirements. Through simulation experiments, we confirmed that our proposal effectively routed multimedia packets over a logical path avoiding congested links. As a result, the load on a network is well distributed and the network can accommodate more sessions than QOLSR. We also conducted practical experiments using wireless ad-hoc relay nodes with four network interfaces and verified the practicality of our proposal. 相似文献
92.
Xiangdong Tao Ran Zhang Zhengguo Gao Toshifumi Satoh Toyoji Kakuchi Qian Duan 《Journal of Materials Science》2011,46(19):6396-6401
Poly(N-isopropylacrylamide) with aromatic end groups (Ar-PNIPAM) were synthesized by atom transfer radical polymerization of N-isopropylacrylamide in isopropanol using phenyl 2-chloropropionate, (4′-phenyl)phenyl 2-chloropropionate, and (2′,6′-diphenyl)phenyl
2-chloropropionate as initiators and CuCl/tris(2-dimethylaminoethyl)amine (Me6TREN) as a catalytic system. The resulting polymers had narrow polydispersity index of 1.10–1.14 and molecular weights of
3700–4600 g mol−1. Then, novel functional complexes of Ar-PNIPAM, Europium(III) (Eu(III)), and α-Thenoyltrifluoroacetone (TTA) (Ar-PNIPAM/Eu(III)/TTA)
with thermosensitive and fluorescent properties were synthesized and characterized by Fourier transform infrared spectra and
fluorescence spectroscopy. Metal Eu(III) was not only bonded to oxygen and nitrogen atoms of polymer chain in PNIPAM, but
also bonded to TTA. The maximum emission intensity of the complexes at 613 nm was enhanced about 22, 27, 33 times compared
with that of the corresponding Eu(III). The lower critical solution temperatures (LCSTs) of Ar-PNIPAM/Eu(III)/TTA were slightly
greater compared with that of PNIPAM. Eu(III) complexes had excellent fluorescence performance, the fluorescence spectrum
presented characteristic emission of Eu(III) at 613 nm. 相似文献
93.
94.
Yoshihisa Ohashi Kentaro Uchida Kensuke Fukushima Masashi Satoh Tomohisa Koyama Maho Tsuchiya Hiroki Saito Katsufumi Uchiyama Naonobu Takahira Gen Inoue Masashi Takaso 《International journal of molecular sciences》2022,23(21)
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary. 相似文献
95.
T Tanaka H Makita T Kawamori K Kawabata H Mori A Murakami K Satoh A Hara H Ohigashi K Koshimizu 《Canadian Metallurgical Quarterly》1997,18(5):1113-1118
The modifying effect of dietary administration of a xanthine oxidase inhibitor 1'-acetoxychavicol acetate (ACA) present in an edible plant Languas galanga in Thailand on the development of azoxymethane (AOM)-induced colonic aberrant crypt foci (ACF) was investigated in rats. Male F344 rats were given s.c. injections of AOM (15 mg/kg body wt) once a week for 3 weeks to induce colonic ACF. They were fed the diets containing 100 or 200 ppm ACA for 5 weeks, starting 1 week before the first dosing of AOM. At the termination of the study (week 5), AOM induced 118 +/- 28 ACF/colon. Dietary administration of ACA caused significant reduction in the frequency of ACF (41% inhibition by 100 ppm ACA feeding and 37% inhibition by 200 ppm ACA feeding, P<0.01). Such inhibition might be associated with suppression of the proliferation biomarkers' expression such as ornithine decarboxylase activity in the colonic mucosa, number of silver-stained nucleolar organizer regions' protein in the colonic mucosal cell nuclei and blood polyamine content. These results indicate that ACA could inhibit the development of AOM-induced ACF through its suppression of cell proliferation in the colonic mucosa and ACA might be a possible chemopreventive agent against colon tumourigenesis. 相似文献
96.
97.
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99.
M Ito K Abumi N Takeda S Satoh K Hasegawa K Kaneda 《Canadian Metallurgical Quarterly》1998,23(19):2127-2133
STUDY DESIGN: Pathologic features of hemodialysis-associated spinal disorders were evaluated using preoperative radiographic images and histologic findings of the spinal lesions resected during surgery. OBJECTIVES: To investigate the pathology of hemodialysis-related spinal disorders and to determine the role of amyloidosis in the establishment of severe destruction of the spine. SUMMARY OF BACKGROUND DATA: The pathologic events leading to hemodialysis-associated spinal disorders are poorly understood. The distribution of amyloid deposits in the spine also has not been clarified. METHODS: Twenty patients with hemodialysis-associated spinal disorders were investigated regarding pathologic features of neural compression and spinal destruction. Preoperative radiographic images such as plain radiography, tomography, computed tomography, magnetic resonance imaging, and scintigraphy were assessed for the existence of an intracanal mass, hypertrophy of the ligamentum flavum, and destructive changes of the spinal components. Histologic examination also was conducted by light microscopy and scanning electron microscopy to determine the distribution pattern of amyloid deposits in the spinal components. RESULTS: Six patients with no destructive changes in the spine showed spinal canal stenosis. In the cervical spine, a main factor associated with spinal canal stenosis was the presence of intracanal amyloid deposits in three patients. In the lumbar spine, a main factor associated with spinal canal stenosis was hypertrophied ligamentum flavum in three patients. Destructive changes of the facet joints, intervertebral disc, and vertebral body were seen in the other 14 patients. Amyloid deposits were densely distributed at the enthesis of capsular fibers to the bone and in anular tears in the intervertebral discs. Vertebral end plates were destroyed by penetration of amyloid granulation into the vertebral body. Osteoclast activity in the destroyed vertebral bodies was enhanced, with no evidence of new bone formation. CONCLUSIONS: Amyloid deposits played an important role in the progression of spinal destruction and severe instability. 相似文献
100.
H Naganuma A Sasaki E Satoh M Nagasaka S Nakano S Isoe K Tasaka H Nukui 《Canadian Metallurgical Quarterly》1996,36(11):789-795
The effect of transforming growth factor-beta (TGF-beta) secreted by glioblastoma (T98G) cells on the secretion of interferon-gamma (IFN-gamma) by lymphokine-activated killer (LAK) cells stimulated with tumor cells was investigated in cocultures of LAK and Daudi cells supplemented with T98G culture supernatant, T98G culture supernatant preincubated with anti-TGF-beta 1 and anti-TGF-beta 2 neutralizing antibodies, anti-TGF-beta 1 and anti-TGF-beta 2 antibodies, or natural human TGF-beta 1 or recombinant human TGF-beta 2. LAK cells were incubated with anti-TGF-beta 1 and anti-TGF-beta 2 antibodies, and with T98G cells of which the supernatant contained both active and latent forms of TGF-beta 1 and TGF-beta 2, with or without neutralizing antibodies. Addition of the supernatant from T98G cells to LAK/Daudi culture caused inhibition of IFN-gamma secretion by LAK cells. The inhibition was abolished by pretreatment of the supernatants with anti-TGF-beta antibodies. Addition of TGF-beta 1 and TGF-beta 2 to the LAK/Daudi culture inhibited IFN-gamma secretion by LAK cells in a dose-dependent manner. Addition of anti-TGF-beta antibodies to the LAK culture resulted in increased IFN-gamma secretion. T98G cells failed to stimulate LAK cells to secrete more IFN-gamma. Addition of anti-TGF-beta antibodies to the LAK-T98G culture resulted in increased IFN-gamma secretion by LAK cells. These results suggest that most malignant glioma cells which secrete high levels of TGF-beta can inhibit IFN-gamma secretion by LAK cells even after tumor cell stimulation. 相似文献