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The effects of a new series of glutarimide compounds have been studied in acetylcholine induced auricular fibrillation in anaesthetized cats and epinephrine induced ventricular arrhythmmias in conscious pigeons. Some of the compounds showed varying degree of protective action against experimental arrhythmias. However these compounds were found to be less potent than quinidine. The mechanism of antiarrhythmic action has been discussed. 相似文献
575.
The presence of 50-200 microM aurintricarboxylic acid (ATA) blocked the uptake of [3H]-triamcinolone acetonide (3H-TA)-receptor complex from rat liver cytosol by isolated nuclei. The half-maximal inhibition (I.D.50) in the nuclear uptake of [3H]-TA-receptor complex was observed at 70- and 80 microM ATA depending upon whether the inhibitor was added prior to or following receptor activation. In addition, the nuclear-bound [3H]-TA-receptor complex from control samples could be completely extracted by an incubation with 20-100 microM ATA. The amount of [3H]-TA-receptor complex remained unchanged under these conditions. The effects of ATA may result due to its interaction with the glucocorticoid receptor at/near the sites that are involved in its nuclear uptake. ATA, therefore is a potentially useful chemical probe for analysis of glucocorticoid receptor. 相似文献
576.
LL Altshuler L Cohen MP Szuba VK Burt M Gitlin J Mintz 《Canadian Metallurgical Quarterly》1996,153(5):592-606
OBJECTIVE: Given concerns about use of psychotropic medication during pregnancy, the authors reviewed the literature regarding the effects of prenatal exposure to psychotropic medications on fetal outcome. METHOD: A MEDLINE search of all articles written in English from 1966 to 1995 was performed to review information on the effects of psychotropic drug use during pregnancy on fetal outcome. Where sufficient data were available and when methodologically appropriate, meta-analyses were performed to assess risk of fetal exposure by psychotropic medication class. RESULTS: Three primary effects are associated with medication use during pregnancy: 1) teratogenicity, 2) perinatal syndromes (neonatal toxicity), and 3) postnatal behavioral sequelae. For many drug classes there are substantial data regarding risk for teratogenicity. Tricyclic antidepressants do not seem to confer increased risk for organ dysgenesis. The available data indicate that first-trimester exposure to low-potency phenothiazines, lithium, certain anticonvulsants, and benzodiazepines may increase the relative risk for congenital anomalies. However, the absolute risk of congenital malformations following prenatal exposure to most psychotropics is low. CONCLUSION: Exposure to certain psychotropic drugs in utero may increase the risk for some specific congenital anomalies, but the rate of occurrence of these anomalies even with the increased risk remains low. Use of psychotropic medications during pregnancy is appropriate in many clinical situations and should include thoughtful weighing of risk of prenatal exposure versus risk of relapse following drug discontinuation. The authors present disorder-based guidelines for psychotropic drug use during pregnancy and for psychiatrically ill women who wish to conceive. 相似文献
577.
Intact mycobacteria and mycobacterial cell wall extracts have been shown to inhibit the growth of human and murine bladder cancer. Their mechanism of action is, however, poorly understood. Mycobacterium phlei mycobacterial cell complex (MCC) is a cell wall preparation that has mycobacterial DNA in the form of short oligonucleotides complexed on the cell wall surface. In this study, we have investigated the possibility that MCC has anti-cancer activity that is mediated by two different mechanisms--a direct effect on cancer cell proliferation and viability and an indirect effect mediated by the production of interleukin 12 (IL-12), a cytokine known to possess anti-cancer activity. We have found that, although MCC is a potent inducer of IL-12 and IL-6 synthesis in monocytes and macrophages either in vitro or in vivo, it is unable to induce the synthesis of either IL-12, IL-6 or granulocyte-macrophage colony-stimulating factor (GM-CSF) by the human transitional bladder cancer cell lines HT-1197 and HT-1376. MCC is not directly cytotoxic towards these cancer cells, but induces apoptosis as determined by nuclear DNA fragmentation and by the release of nuclear mitotic apparatus protein. Mycobacterium phlei DNA associated with MCC is responsible for the induction of apoptosis. Our results indicate that MCC directly effects bladder cancer cells by inhibiting cellular proliferation through the induction of apoptosis, and has the potential for an indirect anti-cancer activity by stimulating cancer-infiltrating monocytes/macrophages to synthesize IL-12. 相似文献