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101.
We report a unique case of tubular polyclonal immunoglobulin G (IgG) deposition disease (PIDD) superimposed on diabetic nephropathy in an 84-year-old man presenting with subacute renal failure and proteinuria. The deposits were located exclusively between the tubular epithelial cells and the tubular basement membranes (TBMs) and stained intensely with antisera to IgG heavy chain and both kappa and lambda light chains. Electron microscopy revealed large predominantly extracellular electron-dense deposits with a distinctive curvilinear substructure. The associated light microscopic findings of tubular simplification with features of acute tubular necrosis implicate this tubulopathy as the cause of the acute renal failure. This appears to represent a unique entity that does not fit into any previously described category of renal tubular immune complex or immunoglobulin deposition disease. 相似文献
102.
BP Bergeron 《Canadian Metallurgical Quarterly》1998,104(5):39-43
Alterations caused by hypothermal stress in neurons of pelvic plexus in rats were studied histochemically. The increase of catecholamine content in neurons and serotonin--in small intensely fluorescent cells (SIFC), suppression of acetyl cholinesterase activity in neurons were demonstrated after the short-term hypothermal stress leading to moderate hypothermia. Cooling of rats following the preliminary section of pelvic nerves does not prevent the above mentioned changes in neurons and SIFC. The participant of adrenergic nerves and SIFC in peripheral mechanisms of thermoregulation is under discussion. 相似文献
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104.
Effects of increasing extracellular K+ or intracellular Na+ concentrations on glucose metabolism in cultures of rat astroglia and neurons were examined. Cells were incubated in bicarbonate buffer, pH 7.2, containing 2 mM glucose, tracer amounts of [14C]deoxyglucose ([14C]dGlc), and 5.4, 28, or 56 mM KCl for 10, 15, or 30 min, and then for 5 min in [14C]dGlc-free buffer to allow efflux of unmetabolized [14C]dGlc. Cells were then digested and assayed for labeled products, which were shown to consist of 96-98% [14C]deoxyglucose 6-phosphate. Increased K+ concentrations significantly raised [14C]deoxyglucose 6-phosphate accumulation in both neuronal and mixed neuronal-astroglial cultures at 15 and 30 min but did not raise it in astroglial cultures. Veratridine (75 microM), which opens voltage-dependent Na+ channels, significantly raised rates of [14C]dGlc phosphorylation in astroglial cultures (+20%), and these elevations were blocked by either 1 mM ouabain, a specific inhibitor of Na+,K(+)-ATPase (EC 3.6.1.37), or 10 microM tetrodotoxin, which blocks Na+ channels. The carboxylic sodium ionophore, monensin (10 microM), more than doubled [14C]dGlc phosphorylation; this effect was only partially blocked by ouabain and unaffected by tetrodotoxin. L-Glutamate (500 microM) also stimulated [14C]dGlc phosphorylation in astroglia--not through N-methyl-D-aspartate or non-N-methyl-D-aspartate receptor mechanisms but via a Na(+)-dependent glutamate-uptake system. These results indicate that increased uptake of Na+ can stimulate energy metabolism in astroglial cells. 相似文献
105.
Despite its obscure and short effect, plasma exchange (PE) remains a mainstay in the treatment of liver disease. However, the question still remains as to whether or not PE suppresses the regeneration of the liver because PE deprives patients of hepatotrophic factors. The effect of PE, which could be a total blood exchange (TBE) in a syngeneic setting, on liver regeneration following a 68% partial hepatectomy (PH) was investigated in rats. In Group 1, 20 ml of blood from normal rats was infused while native blood was removed at 6 and 12 h after PH. In Group 2, 20 ml of blood obtained from PH rats at the same time points was infused. The regeneration rate, labeling index of proliferating cell nuclear antigen (PCNA), and plasma hepatocyte growth factor (HGF) level were determined, and standard liver function tests performed at 24, 48, and 72 h. Although all liver function tests improved in Group 1 at 24 and 48 h, the regeneration rate was significantly impaired. Similarly, the PCNA labeling index was significantly lower in Group 1 than that in Group 2. The plasma HGF level was significantly reduced in Group 1 (6 h blood out versus blood in: 1.1+/-0.5 vs. 0.1+/-0.1 ng/ml, p < 0.05). TBE with normal blood following PH suppressed the early stage of liver regeneration, in part, because of the reduction of HGF even though the blood was purified. 相似文献
106.
R Mukhopadhyay S Dey N Xu D Gage J Lightbody M Ouellette BP Rosen 《Canadian Metallurgical Quarterly》1996,93(19):10383-10387
Leishmania resistant to arsenicals and antimonials extrude arsenite. Previous results of arsenite uptake into plasma membrane-enriched vesicles suggested that the transported species is a thiol adduct of arsenite. In this paper, we demonstrate that promastigotes of arsenite-resistant Leishmania tarentolae have increased levels of intracellular thiols. High-pressure liquid chromatography of the total thiols showed that a single peak of material was elevated almost 40-fold. The major species in this peak was identified by matrix-assisted laser desorption/ionization mass spectrometry as N1,N8-bis-(glutathionyl)spermidine (trypanothione). The trypanothione adduct of arsenite was effectively transported by the As-thiol pump. No difference in pump activity was observed in wild type and mutants. A model for drug resistance is proposed in which Sb(V)/As(V)-containing compounds, including the antileishmanial drug Pentostam, are reduced intracellularly to Sb(III)/As(III), conjugated to trypanothione, and extruded by the As-thiol pump. The rate-limiting step in resistance is proposed to be formation of the metalloid-thiol pump substrates, so that increased synthesis of trypanothione produces resistance. Increased synthesis of the substrate rather than an increase in the number of pump molecules is a novel mechanism for drug resistance. 相似文献
107.
108.
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110.
BP Imbimbo U Lucca F Lucchelli M Alberoni LJ Thal 《Canadian Metallurgical Quarterly》1998,12(4):313-322
Studies of Pneumocystis carinii have been limited by our inability to propagate it in continuous culture. In this context, studies of P. carinii antigens have provided significant insight into the biology of this organism. The mannose-rich surface major surface glycoprotein of P. carinii termed glycoprotein A (gpA) is the best studied of these P. carinii antigens. Significant genetic and immunologic diversity exists between the gpA molecules expressed by P. carinii derived from different mammalian sources. The molecular and biochemical nature of gpA and other P. carinii antigens including p55 are reviewed. In addition, available information concerning the role of P. carinii gpA and other antigens in host-organism interactions are also discussed. 相似文献