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121.
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K Hosohata RM Quock Y Hosohata TH Burkey A Makriyannis P Consroe WR Roeske HI Yamamura 《Canadian Metallurgical Quarterly》1997,61(9):PL115-PL118
AM630 has been demonstrated to be a cannabinoid receptor antagonist in the mouse brain and vas deferens. Conversely, it was recently reported that AM630 acts as a cannabinoid agonist in the guinea pig ileum. This research was designed to determine whether the difference in the action of AM630 is species specific. Studies conducted in guinea pig brain reveal that AM630 antagonizes the stimulatory effect of the cannabinoid agonist WIN 55,212-2 on [35S]GTPgammaS binding suggesting that difference in AM630 activity in different tissues is not due to species variation. 相似文献
123.
A generalized model for 3-μm (4I 11/2 →4I 13/2)Er lasers is proposed. The essential energy transfer processes present in the single-doped Er 3+ systems (up-conversion from 4I 13/2, up-conversion from 4 I 11/2, cross-relaxation from 4S 3/2), as well as those present in Cr3+ codoped Er 3+ systems, are taken into account. In the frame of this model, the main features of 3 μm Er3+ lasers, such as long pulse or CW operation, the change of emission wavelength as a function of pumping conditions, and the effects of codoping with Ho3+ or Tm3+ ions, are explained 相似文献
124.
Myospherulosis is a rare condition. The authors report a unique case of this entity arising in paranasal sinus. The review of literature with emphasis on pathogenesis is also discussed. 相似文献
125.
The paper deals with interaction phenomena concerning double-symmetrical rolled compressed members.
Using an original model of analysis based upon a second-order analysis, a formula for the determination of the ultimate force Pu is given. This formula is valid in the elastic range. 相似文献
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HI Magazine Y Liu TV Bilfinger GL Fricchione GB Stefano 《Canadian Metallurgical Quarterly》1996,156(12):4845-4850
We evaluated the contribution of nitric oxide (NO) to morphine-induced rounding of spontaneously activated (mobile) ameboid human monocytes, granulocytes, or arterial endothelial cells and invertebrate immunocytes and microglia. Morphine induced significant rounding and inactivation of ameboid cells within 20 min except for arterial endothelial cells, which became rounded 24 h after morphine exposure. The effects of morphine on cell conformation were blocked in the presence of N-nitro-L-arginine, a nitric oxide synthase inhibitor. Treatment of cells with the NO donor, sodium nitroprusside, induced cell rounding similar to that observed following morphine exposure, suggesting that NO release may mediate morphine-induced changes in cell conformation. The contribution of NO release to morphine-induced cell rounding was determined by direct evaluation of NO concentration in real-time using a NO-specific amperometric probe. Significant increases in NO concentration were observed 2 min after morphine stimulation, whereas morphine-induced NO release was markedly impaired by pretreatment with N-nitro-L-arginine or the opiate alkaloid antagonist, naloxone. In contrast, opioid peptides failed to induce NO release, consistent with our previous observations that demonstrated the failure of opioid peptides to promote cell rounding. Taken together, these data suggest that morphine-induced NO release may be mediated by activation of the opiate alkaloid-selective, opioid peptide-insensitive micro3 receptor, and that functional coupling of morphine to NO production has been conserved during evolution and may modulate cellular activation. 相似文献
129.
JD Kang HI Georgescu L McIntyre-Larkin M Stefanovic-Racic WF Donaldson CH Evans 《Canadian Metallurgical Quarterly》1996,21(3):271-277
OBJECTIVE: To estimate the prevalence and social correlates of cardiovascular disease. DESIGN: Population-based cross-sectional survey. Survey data were obtained through a standardized home interview and a clinic visit by trained nurses. The question sequence of the London School of Hygiene (the Rose Questionnaire) was used to identify the presence of definite angina, possible infarction, definite infarction, intermittent claudication and stroke. SETTING: Eight urban communities and rural areas in Saskatchewan in 1990. PARTICIPANTS: A probability sample of 2167 noninstitutionalized men and women aged 18 to 74 years who participated in the Saskatchewan Heart Health Survey. MAIN OUTCOME MEASURES: Prevalence of cardiovascular diseases. RESULTS: Among men, the prevalence of definite angina increased gradually with age from 1.7% (95% CI 0.6% to 2.7%) in the 18 to 34 year group, 3.8% (1.3% to 6.0%) in the 35 to 54 year group to 4.8% (2.8% to 8.3%) in the 55 to 74 year group, while the prevalence among women ranged from 2.5% (1.2 to 3.7%), 4.0% (1.6% to 6.5%) to 7.1% (5.1% to 11.6%) in these same age groups. The prevalence of possible angina, definite infarction, possible infarction and intermittent claudication increased with age as well, being higher in men than in women. Generally, the conditions were more prevalent among those with less education, lower income and those who were unemployed. CONCLUSIONS: These findings indicate that there is sociodemographic inequality in the prevalence of these manifestations of cardiovascular disease, and there is a need for in-depth qualitative research into causal factors in this relationship and for targeted programs of health promotion. 相似文献
130.
Recently, wild-type SV40 and/or DNA sequences indistinguishable from SV40 have been detected in specific types of human tumors: ependymoma and choroid plexus tumors, mesothelioma, osteosarcoma and sarcoma. The same tumor types will develop in hamsters after injection with SV40. These findings are interesting in themselves for they could shed light on the pathogenesis of these tumors. These findings also have public health implications. SV40 was found to have contaminated the poliovaccines and the adenovaccines from 1955 until 1963, therefore resulting in the inadvertent injection of millions of people with this tumor virus. Moreover, our society pays a high cost for asbestos causality, a carcinogen associated with the development of mesothelioma. In addition to asbestos, the potential impact of finding another possible cause for mesothelioma (i.e., SV40), as well as the possible pathogenic role of the contaminated poliovaccines, has generated considerable public interest and concern. To discuss these recent findings, the NIH (National Institutes of Health) and the FDA (Food and Drug Administration), organized an International Conference at the NIH, Bethesda, MD, January 27-28, 1997. The association of SV40 with human mesothelioma was also discussed in a special session at the IV International Mesothelioma Conference that was held at the University of Pennsylvania, Philadelphia, PA, May 13-16, 1997. The purpose of this review is to summarize data, from the discovery of the contaminated poliovaccines, to the most recent findings presented at the meetings in Bethesda and Philadelphia, to discuss technical and other problems associated with this research, and the potential for using these findings to develop new diagnostic and therapeutic approaches for SV40-associated malignancies. 相似文献