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排序方式: 共有706条查询结果,搜索用时 17 毫秒
611.
Y Kuriyama M Nakano Y Kawanishi O Iwase S Aizawa K Toyama 《Canadian Metallurgical Quarterly》1995,9(12):2123-2126
In order to analyze systemic immune surveillance in patients with B cell non-Hodgkin's lymphomas (B-NHL), we investigated circulating lymphocytes using two-color flow cytometry. The proportions of CD3-CD56+ natural killer (NK) cells and CD8++(bright) S6F1++ killer-effector T cells corresponding to activated cytotoxic T lymphocytes (aCTL) were studied in the peripheral blood of 26 patients with indolent lymphoma (IL) and 24 with aggressive lymphoma (AL). The AL patients with both limited disease and advanced disease had an increased proportion of NK cells. However, this feature was not evident in IL patients with either limited or advanced disease. In contrast, an increased proportion of aCTL was observed only in IL patients with advanced disease. These findings indicate that IL may differ from AL in terms of immune surveillance against neoplastic B cells. 相似文献
612.
In order to search for the origin of vascular lesion from the hydrodynamic point of view, the viscous flows in a constricted
channel and in a channel with a branch are studied numerically. The results obtained show the importance of the temporal variation
of shearing stress on the wall. 相似文献
613.
H Sawanishi S Wakusawa R Murakami H Muramatsu H Suzuki A Takashima T Aizawa K Miyamoto 《Canadian Metallurgical Quarterly》1995,38(26):5066-5070
1,3,5-Triazacycloheptanes were synthesized and examined for reversal of the multidrug resistance dependent on P-glycoprotein. Most of these compounds increased the intracellular uptake of vinblastine in multidrug-resistant mouse leukemia P388/ADR cells without influence upon the vinblastine accumulation in P388/S cells. The efficacy of 1,5-dibenzyl-1,3,5-triazacycloheptanes in increasing the vinblastine accumulation was in the order of 2,4-dithioxo (5) > 2-oxo-4-thioxo (4) approximately 4-(methylthio)-2-oxo (6) > 2,4-dioxo (2). The efficacy was further increased when the benzyl group was converted to a chlorobenzyl group. Among these compounds, 6c [1,5-bis(4-chlorobenzyl)-1,5,6,7-terahydro-4-(methylthio)-2H-1,3,5 - triazepin-2-one] potentiated the in vitro cell growth-inhibitory effect of vinblastine, adriamycin, and mitomycin C on P388/ADR cells and prolonged the life span of P388/ADR-bearing mice in combined therapy with vinblastine more than vinblastine alone. 相似文献
614.
Suetake Tetsuya; Aizawa Tomoyasu; Koganesawa Nozomi; Osaki Tsukasa; Kobashigawa Yoshihiro; Demura Makoto; Kawabata Shun-ichiro; Kawano Keiichi; Tsuda Sakae; Nitta Katsutoshi 《Protein engineering, design & selection : PEDS》2002,15(9):763-769
Tachycitin is an invertebrate chitin-binding protein with anamidated C-terminus, and possesses antimicrobial activity againstboth fungi and bacteria. The 1H-NMR-based tertiary structureof tachycitin was recently determined [Suetake et al. (2000)J. Biol. Chem., 275, 1792917932]. In order to examinethe structural and functional features of tachycitin more closely,we performed for the first time, gene expression, refolding,15N-NMR-based characterizations, and antimicrobial activitymeasurements of a recombinant tachycitin (rTcn) that does nothave the amide group at the C-terminus. The NMR analysis indicatedthat rTcn possesses the same structural construction as thenative tachycitin. The backbone 15N relaxation measurementsshowed that the molecular motional correlation time of rTcnincreases as its concentration increases, indicating that tachycitinshave a tendency to aggregate with each other. rTcn exhibitsantimicrobial activity against fungi but not against bacteria.The cell surface of fungi contains chitin as an essential constituent,but that of bacteria does not. These results suggest that notonly the chitin-binding region but also the C-terminal amidegroup of tachycitin plays a significant role in its antimicrobialproperties. 相似文献
615.
K Matsumoto H Aizawa H Inoue M Shigyo S Takata N Hara 《Canadian Metallurgical Quarterly》1996,81(6):2358-2364
We investigated the role of neurogenic inflammation and the subsequent mechanisms in cigarette smoke-induced airway hyperresponsiveness in guinea pigs. Exposure to cigarette smoke was carried out at tidal volume for 3 min. Airway responsiveness to histamine was determined before and after smoke exposure followed by bronchoalveolar lavage (BAL). Plasma extravasation was evaluated by measuring the extravasation of Evans blue dye in the airway. Cigarette smoke produced significant airway hyperresponsiveness and plasma extravasation, with an influx of neutrophils in BAL fluid. FK-224 (10 mg/kg i.v.), a tachykinin antagonist at NK1 and NK2 receptors, significantly inhibited these changes. The thromboxane (Tx) B2 concentration was increased in BAL fluid after smoke exposure and was significantly inhibited by FK-224. OKY-046 (10 mg/kg i.v.), a Tx synthase inhibitor, significantly inhibited airway hyperresponsiveness but had no effect on neutrophil influx or plasma extravasation. The results suggest that neurogenic inflammation and the subsequent generation of Tx in the airway are important in the development of the airway hyperresponsiveness induced by cigarette smoke. 相似文献
616.
Research has demonstrated the importance of psychological factors in coping, quality of life, and disability in chronic pain. Furthermore, the contributions of psychology in the effectiveness of treatment of chronic pain patients have received empirical support. The authors describe a biopsychosocial model of chronic pain and provide an update on research implicating the importance of people's appraisals of their symptoms, their ability to self-manage pain and related problems, and their fears about pain and injury that motivate efforts to avoid exacerbation of symptoms and further injury or reinjury. They provide a selected review to illustrate treatment outcome research, methodological issues, practical, and clinical issues to identify promising directions. Although there remain obstacles, there are also opportunities for psychologists to contribute to improved understanding of pain and treatment of people who suffer from chronic pain. The authors conclude by noting that pain has received a tremendous amount of attention culminating in the passage of a law by the U.S. Congress designating the period 2001-2011 as the "The Decade of Pain Control and Research." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
617.
Beer foam polypeptides have been separated into five groups based on their relative hydrophobicity. Foam stability increases with increasing hydrophobicity of the polypeptide groups. The most hydrophobic polypeptide group contains a large proportion of Coomassie blue-binding polypeptides. Analysis by SDS-PAGE reveals that each polypeptide group is composed of several differently-sized polypeptides. Further purification by anion-exchange chromatography results in five fractions, each of which has a different polypeptide profile on SDS-polyacrylamide gels. 相似文献
618.
An Interactive Multimedia Diary for the Home 总被引:2,自引:0,他引:2
A system for retrieval and summarization of multimedia data from a home-like environment continuously captures video and audio sequences as the inhabitants are moving inside the house. An interactive user interface based on hierarchical media segmentation incorporates user memory and intelligence data. In the long term, this system can provide valuable information for studies related to housing design, evaluating human behavior, and so on. 相似文献
619.
K Watanabe K Toba Y Ogawa Y Aizawa N Tanabe S Miyajima Y Kusano T Nagatomo Y Hirokawa 《Canadian Metallurgical Quarterly》1997,34(12):1125-1130
The CD36 molecule is a multifunctional membrane type receptor glycoprotein that reacts with thrombospondin, collagen, oxidized LDL and long-chain fatty acids (LCFA). LCFA are one of the major cardiac energy substrates, hence LCFA metabolism may have an important role in cardiac diseases. In this study, we analyzed CD36 expression in 200 patients with heart diseases [44 patients with hypertrophic cardiomyopathy (HCM), 16 with dilated cardiomyopathy (DCM), 26 with old myocardial infarction (OMI), 55 with angina pectoris (AP) and 59 with other miscellaneous heart diseases] using a flow cytometer. 123I-beta-methyl-p-iodophenylpentadecanoic acid (BMIPP) myocardial accumulation was also examined in some patients. Eight patients (2 with HCM, 1 with DCM, 2 with OMI, and 3 with AP) were diagnosed as having type I CD36 deficiency (neither platelets nor monocytes expressed CD36). Sixteen patients (3 with HCM, 1 with DCM, 1 with OMI, 8 with AP, and 3 with other heart diseases) showed type II CD36 deficiency (monocytes expressed CD36 but platelets did not). In all 8 patients with type I CD36 deficiency, there was no BMIPP accumulation in the heart. However, in 13 patients with type II CD36 deficiency, focally reduced BMIPP accumulation was observed, but there were no patients without BMIPP accumulation. CD36 deficiency was observed in a higher proportion (12%) of patients with heart disease in this study than in a reported control study. Type I CD36 deficiency is associated with absence of BMIPP accumulation in the heart, hence it may have an important role in LCFA metabolic disorders and some types of cardiac hypertrophy as well as other heart diseases. 相似文献
620.
H Asanuma AH Thompson T Iwasaki Y Sato Y Inaba C Aizawa T Kurata S Tamura 《Canadian Metallurgical Quarterly》1997,202(2):123-131
SETTING: Mycobacterial galactofuran is essential to the linking of the peptidoglycan and mycolic acid cell wall layers. Galactofuran biosynthesis should thus be essential for viability. OBJECTIVE: The objective was to determine the pathway of galactofuranosyl biosynthesis and to clone a gene encoding an essential enzyme necessary for its formation. DESIGN: Specific enzymatic conversions involved in formation of galactopyranose and galactofuranose residues in other bacteria were tested for in Mycobacterium smegmatis. M. tuberculosis deoxyribonucleic acid (DNA) was identified by homology. RESULTS: It was shown that the de novo synthesis of the galactose carbon skeleton occurred in M. smegmatis by the transformation of UDP-glucopyranose to UDP-galactopyranose via the enzyme UDP-glucose 4-epimerase (E.C. 5.1.3.2). The N-terminal sequence of this enzyme was obtained after purification. The galactose salvage pathway enzyme, UDP-glucose-galactose-1-phosphate uridylyltransferase (E.C. 2.7.7.12), was also shown to be present. The critical biosynthetic transformation of the galactopyranose to galactofuranose ring form was shown to occur at the sugar nucleotide level via the enzyme UDP-galactopyranose mutase (E.C. 5.4.99.9). The M. tuberculosis DNA encoding this enzyme was sequenced, the gene expressed in Escherichia coli, and the expected enzymatic activity demonstrated. CONCLUSION: Galactofuranose biosynthesis can now be pursued as a potential drug target in M. tuberculosis. 相似文献