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191.
EE Schott SW Fitzgerald WJ McCarthy AA Nemcek AH Sonin 《Canadian Metallurgical Quarterly》1997,169(1):59-61
A case of intramuscular hemangioma (large vessel type) occurring in an eighteen year old woman is described. Medical history reported a pulled muscle in the same region 5 years earlier. By needle biopsy was performed the diagnosis of hematoma evolved to sclerosis. Since pain persisted the neoplasia was removed. Intramuscular hemangioma is a benign neoplasia. Recurrences are always due to incomplete excision. Angiosarcomas and liposarcomas are the two tumors to be differentiated from hemangiomas of skeletal muscle. The relative paucity of cases combined with widespread histological pictures make the diagnosis very difficult. 相似文献
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EE Daniel AM Low V Gaspar H Lu-Chao J Green J Akrong S Duerksen C Soyka CK Chen J Boyd CY Kwan 《Canadian Metallurgical Quarterly》1996,117(7):1535-1543
1. We investigated the nature of the adrenoceptors in the dog saphenous vein (DSV) and dog mesenteric vein (DMV) to determine the nature of the unexpected interactions of phenylephrine and methoxamine with rauwolscine in the DSV, i.e. the ability of the putative alpha 2-adrenoceptor antagonist to inhibit competitively contractions to these alpha 1-agonists. Radioligand binding studies were performed in parallel with contractility studies. 2. Functionally, in the DSV, phenylephrine and methoxamine-induced, contractions were antagonized by rauwolscine with Schild slopes of -0.52 and -0.46, respectively and apparent pA2 values of 8.5 and 9.2, respectively. Such antagonism was not observed in the DMV. In the DSV, prazosin competes for [3H]-rauwolscine binding sites with a high and a low affinity binding site (Ki of 1.49 +/- 0.65 and 94.7 +/- 51 microM, n = 6, respectively). 3. Pretreatment with 100 microM chloroethylclonidine (CEC) for 15 min abolished [3H]-prazosin binding in microsomes from both veins and reduced binding (Bmax) of [3H]-rauwolscine in microsomes by 55.1 +/- 0.8% (n = 3) in the DSV but did not affect the Bmax in the DMV. CEC pretreatment in the venular rings denuded of endothelium caused persistent contraction in the DSV but not in the DMV. In the DSV, CEC appeared to interact with a single [3H]-rauwolscine binding site. In both the DSV and the DMV, CEC (100 microM) caused a significant shift in the EC50 values for phenylephrine and methoxamine. Maximum responses in the DMV were significantly attenuated while those in the DSV were unaffected when total tension was considered. 4. Studies of the functional interactions of the DSV and the DMV with WB 4101 or 5-methylurapidil (5-MU) suggested the presence of alpha 1D-adrenoceptors in the DSV and alpha 1A-adrenoceptors in the DMV. The receptors inactivated by CEC in the DMV and DSV may represent some or all of the receptors with properties of alpha 1D and alpha 1A-receptors present in the two veins. Studies of radioligand binding interactions of these two antagonists with [3H]-prazosin, were consistent with the presence of some alpha 1D-receptors in DSV and alpha 1A-receptors in DMV. These findings raise questions about the selectivity of CEC in differentiating alpha 1-adrenoceptor subtypes. 5. B-HT 920 caused contractions in the DSV smaller than those to the alpha 1-agonists but the maximum was not affected by CEC pretreatment. The EC50 values were shifted to the left after CEC. In radioligand binding studies, B-HT 920 competition for [3H]-rauwolscine binding was not significantly affected by CEC pretreatment. 6. These results suggest the presence of unusual alpha-adrenoceptors in the DSV. In addition to alpha 2-adrenoceptors, receptors recognizing rauwolscine as well as prazosin, WB 4101, phenylephrine and methoxamine and susceptible to inactivation by CEC are present. They appear to be, in part, unusual alpha 1D-adrenoceptors. 相似文献
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BACKGROUND: Cell-permeable small molecules that target predetermined DNA sequences with high affinity and specificity have the potential to control gene expression. A binary code has been developed to correlate DNA sequence with side-by-side pairings between N-methylpyrrole (Py) and N-methylimidazole (Im) carboxamides in the DNA minor groove. We set out to determine the relative energetics of pairings of Im/Py, Py/Im, Im/Im, and Py/Py for targeting G.C and A.T base pairs. A key specificity issue, which has not been previously addressed, is whether an Im/Im pair is energetically equivalent to an Im/Py pair for targeting G.C base pairs. RESULTS: Equilibrium association constants were determined at two five-base-pair sites for a series of four six-ring hairpin polyamides, in order to test the relative energetics of the four aromatic amino-acid pairings opposite G.C and A.T base pairs in the central position. We observed that a G.C base pair was effectively targeted with Im/Py but not Py/Im, Py/Py, or Im/Im. The A.T base pair was effectively targeted with Py/Py but not Im/Py, Py/Im, or Im/Im. CONCLUSIONS: An Im/Im pairing is energetically disfavored for the recognition of both A.T and G.C. This specificity will create important limitations on undesirable slipped motifs that are available for unlinked dimers in the minor groove. Baseline energetic parameters will thus be created which, using the predictability of the current pairing rules for specific molecular recognition of double-helical DNA, will guide further second-generation polyamide design for DNA recognition. 相似文献
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Y Georgalis EB Starikov B Hollenbach R Lurz E Scherzinger W Saenger H Lehrach EE Wanker 《Canadian Metallurgical Quarterly》1998,95(11):6118-6121
An initial stage of fibrillogenesis in solutions of glutathione S-transferase-huntingtin (GST-HD) fusion proteins has been studied by using dynamic light scattering. Two GST-HD systems with poly-L-glutamine (polyGln) extensions of different lengths (20 and 51 residues) have been examined. For both systems, kinetics of z-average translation diffusion coefficients (Dapp) and their angular dependence have been obtained. Our data reveal that aggregation does occur in both GST-HD51 and GST-HD20 solutions, but that it is much more pronounced in the former. Thus, our approach provides a powerful tool for the quantitative assay of GST-HD fibrillogenesis in vitro. 相似文献