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Because most therapeutic agents used for viral infections are relatively new, experience with their adverse effects is still evolving. Hepatic toxicity has not been among the most important concerns with this class of drugs so far. Liver damage has been increasingly noted with accumulating experience, especially with antiretroviral drugs and those used to treat chronic hepatitis (e.g., fialuridine), but it is often difficult to distinguish between effects of therapy and of the underlying disease. It is important for clinicians to be aware of the possibility of hepatotoxicity in such situations, and further reporting of adverse experiences should contribute to more definitive evaluation of the potential influence of antivirals on liver function. 相似文献
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Sera from 82 cases of leptospirosis (confirmed by micro-agglutination tests or IFAT) and 108 patients with other diseases were investigated using the microcapsule agglutination test (MCAT) for leptospirosis. The overall sensitivity (90.2%), specificity (96.3%), positive predictive value (94.9%), negative predictive value (92.9%), and accuracy of the MCAT (93.7%) were encouraging. MCAT is simple, can be performed by unskilled personnel with minimum laboratory facilities, and produces results in 3 h. MCAT would be a reliable serodiagnostic test for rapidly screening individuals for leptospirosis, in various geographical areas of Thailand. 相似文献
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E Legius H Cuppens H Dierick K Van Zandt R Dom JP Fryns G Evers-Kiebooms M Decruyenaere K Demyttenaere P Marynen 《Canadian Metallurgical Quarterly》1994,2(1):44-50
Pantoprazole is a specific inhibitor of the H+/K(+)-ATPase of the gastric parietal cell. The dose-dependency of a range of pantoprazole pharmacokinetic characteristics was studied. Twelve healthy male subjects were given 10, 20, 40 and 80 mg pantoprazole intravenously according to a randomized, single blind, 4-period change-over scheme. The area under the concentration vs time curve (AUC) and the maximum serum concentration (Cmax) showed a linear increase in line with the dose. Apparent volume of distribution (Vd area), clearance (Cl) and terminal half-life (t1/2) were independent of the dose. The dose-independent elimination of pantoprazole was attributed to the lack of interaction of the drug with cytochrome P450. In clinical practice, a good predictable response, as well as a low potential for interaction with other drugs might be expected. 相似文献
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JP O'Bryan Z Songyang L Cantley CJ Der T Pawson 《Canadian Metallurgical Quarterly》1996,93(7):2729-2734
The Shc adaptor protein, hereafter referred to as ShcA, possesses two distinct phosphotyrosine-recognition modules, a C-terminal Src homology 2 (SH2) domain and an N-terminal phosphotyrosine-binding (PTB) domain, and is itself phosphorylated on tyrosine in response to many extracellular signals. Phosphorylation of human ShcA at Tyr-317 within its central (CH1) region induces binding to the Grb2 SH2 domain and is thereby implicated in activation of the Ras pathway. Two shc-related genes (shcB and shcC) have been identified in the mouse. shcB is closely related to human SCK, while shcC has not yet been found in other organisms. The ShcC protein is predicted to have a C-terminal SH2 domain, a CH1 region with a putative Grb2-binding site, and an N-terminal PTB domain. The ShcC and ShcB SH2 domains bind phosphotyrosine-containing peptides and receptors with a specificity related to, but distinct from, that of the ShcA SH2 domain. The ShcC PTB domain specifically associates in vitro with the autophosphorylated receptors for nerve growth factor and epidermal growth factor. These results indicate that ShcC has functional SH2 and PTB; domains. In contrast to shcA, which is widely expressed, shcC RNA and proteins are predominantly expressed in the adult brain. These results suggest that ShcC may mediate signaling from tyrosine kinases in the nervous system, such as receptors for neurotrophins. 相似文献
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Impact of apolipoprotein E polymorphism on lipoproteins and risk of myocardial infarction. The ECTIM Study 总被引:2,自引:0,他引:2
G Luc JM Bard D Arveiler A Evans JP Cambou A Bingham P Amouyel P Schaffer JB Ruidavets F Cambien 《Canadian Metallurgical Quarterly》1994,14(9):1412-1419
Human apolipoprotein (apo) E, a polymorphic protein with three common alleles, epsilon 2, epsilon 3, and epsilon 4, plays an important role in lipoprotein metabolism. This article describes the association of this polymorphism with lipids, apolipoproteins, and lipoproteins with a particular regard to lipoprotein particles, as defined by their apolipoprotein content, as well as the risk of myocardial infarction in a multicenter population-based case-control study (ECTIM study). In the ECTIM study, 574 male patients aged 25 to 64 were examined 3 to 9 months after myocardial infarction in four regions participating in the World Health Organization MONICA project: Belfast (Northern Ireland) and Lille, Strasbourg, and Toulouse (France). Control subjects (n = 722) were randomly selected from the regional populations. The distribution of apoE phenotypes was significantly different across the four control samples (P = .04), with a higher frequency of the epsilon 4 allele in Belfast (14.3%) than in Toulouse (8.2%). The association of apoE polymorphism with biological measurements was studied in the control groups (n = 640) after men with coronary heart disease or those taking hypolipidemic drugs were omitted, with the apoE3/3 phenotype as a reference after adjustment for concomitant factors. Individuals carrying the epsilon 2 allele had lower levels of plasma cholesterol, low-density lipoprotein cholesterol (LDL-C), and apoB and higher levels of triglycerides, very-low-density lipoprotein cholesterol (VLDL-C), apoC-III, apoE, lipoprotein (Lp) C-III:B, and Lp E:B. However, the effect of the epsilon 2 allele on triglyceride, VLDL-C, apoE, and Lp E:B parameters was heterogeneous across the populations.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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