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991.
RA Vertrees W Tao SD Pencil JP Sites DP Althoff JB Zwischenberger 《Canadian Metallurgical Quarterly》1996,42(4):250-254
Primary aldosteronism is associated with low plasma renin levels, whilst malignant phase hypertension is generally associated with raised renin activity. These two conditions are therefore at opposite ends of the renin spectrum, so in theory their co-existence would be unusual. We describe in detail 3 cases of primary hyperaldosteronism from a disease register of 315 cases of malignant hypertension seen in one medical centre over 29 years. 相似文献
992.
DP Yang KM Goldberg XD Ma W Magargle R Rappaport 《Canadian Metallurgical Quarterly》1998,5(6):780-783
A fluorescent focus identification assay (FFIDA) was developed for use in experimental studies and for quantitation of the components in a tetravalent live oral rotavirus vaccine. The assay utilizes four serotype-specific neutralizing monoclonal antibodies (MAb) to detect and quantify individual rotaviruses by immunofluorescence staining of fixed virus-infected monkey kidney cells. In mixed virus infections, all four MAb, W1 (serotype 1), 1C10 (serotype 2), R1 (serotype 3), and S4 (serotype 4), specifically stain the relevant homologous serotype without exhibiting any cross-reactivity against the other serotypes. Furthermore, the test is sensitive enough to differentiate at least twofold (0.3 log) differences in virus titer. The results of testing four individual experimental vaccine lots three or more consecutive times showed that all four lots contained similar proportions of the four vaccine strains as detected by the classical plaque neutralization identification test. The rapidity and efficiency of the FFIDA are desirable attributes that make it suitable for use in studies requiring identification and quantitation of one or more of the four major rotavirus serotypes. 相似文献
993.
BA Gabre?ls DF Swaab DP de Kleijn A Dean NG Seidah JW Van de Loo WJ Van de Ven GJ Martens FW Van Leeuwen 《Canadian Metallurgical Quarterly》1998,83(11):4026-4033
Wolfram syndrome (WS) is characterized by optic atrophy, insulin-dependent diabetes mellitus, vasopressin (VP)-sensitive diabetes insipidus, and neurosensory hearing loss. Here we report a disturbance in VP precursor processing in the supraoptic and paraventricular nuclei of WS patients. In these patients with diabetes insipidus we could hardly detect any cellular immunoreactivity for processed VP in the supraoptic and paraventricular nuclei. On the other hand, in the paraventricular nucleus a considerable number of cells immunoreactive for the VP precursor were present. In addition, the proprotein convertase PC2 and the molecular chaperone 7B2 were absent. As expression of PC2 and 7B2 was detected in the nearby nucleus basalis of Meynert of one WS patient and in the anterior lobe of the other WS patient, the absence of the two proteins in the paraventricular nucleus was not due to mutations in their genes. These results indicate that in WS patients with diabetes insipidus, not only does VP neuron loss occur in the supraoptic nucleus, but there is also a defect in VP precursor processing. 相似文献
994.
995.
CS Esslinger HP Koch MP Kavanaugh DP Philips AR Chamberlin CM Thompson RJ Bridges 《Canadian Metallurgical Quarterly》1998,8(21):3101-3106
Using an intramolecular [2 + 2] photocyclization, 2,4-methanopyrrolidine-2,4-dicarboxylate was prepared as a conformationally locked analogue of glutamate. This compound, in combination with two other pyrrolidine dicarboxylates, has been used to define the structural elements that differentiate substrate and nonsubstrate inhibitors of a high-affinity, sodium-dependent glutamate transporter. 相似文献
996.
RA Steele DA Emmert J Kao ME Hodsdon C Frieden DP Cistola 《Canadian Metallurgical Quarterly》1998,7(6):1332-1339
Intestinal fatty acid-binding protein (I-FABP) is a cytosolic 15.1-kDa protein that appears to function in the intracellular transport and metabolic trafficking of fatty acids. It binds a single molecule of long-chain fatty acid in an enclosed cavity surrounded by two five-stranded antiparallel beta-sheets and a helix-turn-helix domain. To investigate the role of the helical domain, we engineered a variant of I-FABP by deleting 17 contiguous residues and inserting a Ser-Gly linker (Kim K et al., 1996, Biochemistry 35:7553-7558). This variant, termed delta17-SG, was remarkably stable, exhibited a high beta-sheet content and was able to bind fatty acids with some features characteristic of the wild-type protein. In the present study, we determined the structure of the delta17-SG/palmitate complex at atomic resolution using triple-resonance 3D NMR methods. Sequence-specific 1H, 13C, and 15N resonance assignments were established at pH 7.2 and 25 degrees C and used to define the consensus 1H/13C chemical shift-derived secondary structure. Subsequently, an iterative protocol was used to identify 2,544 NOE-derived interproton distance restraints and to calculate its tertiary structure using a unique distance geometry/simulated annealing algorithm. In spite of the sizable deletion, the delta17-SG structure exhibits a backbone conformation that is nearly superimposable with the beta-sheet domain of the wild-type protein. The selective deletion of the alpha-helical domain creates a very large opening that connects the interior ligand-binding cavity with exterior solvent. Unlike wild-type I-FABP, fatty acid dissociation from delta17-SG is structurally and kinetically unimpeded, and a protein conformational transition is not required. The delta17-SG variant of I-FABP is the only wild-type or engineered member of the intracellular lipid-binding protein family whose structure lacks alpha-helices. Thus, delta17-SG I-FABP constitutes a unique model system for investigating the role of the helical domain in ligand-protein recognition, protein stability and folding, lipid transfer mechanisms, and cellular function. 相似文献
997.
OBJECTIVE: To determine whether electron beam computed tomography (CT) adds to conventional risk factor assessment in the prediction of angiographic coronary artery disease. BACKGROUND: Electron beam CT scanning can be used to predict the severity of coronary atherosclerosis, but whether it does so independently of conventional risk factors is unclear. METHODS: Electron beam CT scans were performed and conventional risk factors were measured in 290 men and women undergoing coronary arteriography for clinical indications. The association of the electron beam CT-derived coronary artery calcium score and conventional risk factors with the presence and severity of angiographically defined coronary atherosclerosis was analyzed by logistic regression and receiver-operator characteristics analysis. RESULTS: Age, the ratio of total cholesterol to high-density lipoprotein (HDL) cholesterol and the coronary calcium score were significantly and independently associated with the presence of any coronary disease and obstructive coronary disease. In association with any coronary disease, odds ratios for age, the ratio of total cholesterol to HDL cholesterol and calcium score, highest quartile vs. lowest quartile, were 6.01 (95% confidence interval 2.87 to 12.56), 3.14 (1.56 to 6.31) and 94.08 (21.06 to 420.12), respectively. For obstructive coronary disease, highest quartile vs. lowest quartile, the respective odds ratios for age, the ratio of total cholesterol to HDL and calcium score were 3.86 (1.86 to 8.00), 4.11 (1.98 to 8.52) and 34.12 (12.67 to 91.86). Male gender was also significantly associated with any coronary disease (odds ratio 2.19, p=0.04) and obstructive coronary disease (odds ratio 2.07, p=0.04). Cigarette smoking was significantly associated with any coronary disease (odds ratio=2.74, p=0.004), and diabetes was significantly associated with obstructive disease (odds ratio 3.16, p=0.01). After adjustment for the coronary calcium score and other risk factors, it was determined that triglycerides, family history and hypertension were not significantly associated with any disease state. A coronary calcium score >80 (Agatston method) was associated with an increased likelihood of any coronary disease regardless of the number of risk factors, and a coronary calcium score > or = 170 was associated with an increased likelihood of obstructive coronary disease regardless of the number of risk factors (p < 0.001). CONCLUSIONS: Electron beam CT scanning offers improved discrimination over conventional risk factors in the identification of persons with any angiographic coronary disease or angiographic obstructive coronary disease. 相似文献
998.
Somatic mutations seem to accumulate slowly with age during adult life in both mice and men. There is, however, a substantial mutant frequency at birth, suggesting that the rate of accumulation is much higher before birth. This suggests that DNA replication plays an important role in the generation of spontaneous mutations. Since most cell division and accompanying DNA replication occurs early in development, more mutations would arise during growth and development. Indeed, if the mutations are genetically neutral, the mutant frequency would rise very rapidly during early fetal growth, more slowly during later fetal growth and development and still more slowly after birth. To test this hypothesis, we have assayed the mutant frequencies from before birth to 28 days after birth, by which time most growth has occurred. We have used the F1 mice generated by crossing SWR females and MutaMouse males. The MutaMouse has a rescuable lacZ/lambda shuttle vector that can be assayed for an in vivo mutation in an in vitro system. Up to and including birth we assayed the entire animal for mutants; at 14 and 28 days after birth we assayed the small intestine. The data show that, as expected, many mutations arise early in development, by 12.5 days after conception, and confirms the non-linearity of mutation with age. In these mice, about one third of mutations arise before birth, about one third during growth to adulthood and the remaining during the rest of the animal's life, although this depends somewhat on the tissue. 相似文献
999.
DP Fourie 《Canadian Metallurgical Quarterly》1998,87(2):536-538
Ataxia-telangiectasia (A-T) is a multisystem recessive disease characterized by cerebellar ataxia, oculocutaneous telangiectasias, immunodeficiency and increased risk of cancer. The ATM gene, responsible for A-T, was recently cloned at human chromosome band 11q22-23, a region of frequent alterations in childhood acute lymphoblastic leukaemia (ALL). Children with A-T frequently develop T-ALL. We investigated 18 T-ALL samples for ATM mutations and loss of heterozygosity (LOH) at the ATM locus. No mutations of ATM were found within the coding region in the 18 T-ALL samples, and LOH at the ATM locus was detected in three. The ATM gene appears to be an infrequently altered tumour suppressor gene in childhood T-ALL. 相似文献
1000.
WT Ford N Qi AL Read JG Smith T Camporesi I Peruzzi M Piccolo RB Hurst KH Lau J Pyrlik JP Venuti HB Wald R Weinstein HR Band MW Gettner GP Goderre JH Moromisato WD Shambroom JC Sleeman von Goeler E WW Ash GB Chadwick RE Leedy RL Messner LJ Moss F Muller HN Nelson DM Ritson LJ Rosenberg DE Wiser RW Zdarko DE Groom PG Verdini MC Delfino JR Johnson TL Lavine T Maruyama R Prepost 《Canadian Metallurgical Quarterly》1987,35(1):408-411