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921.
Infective spondylodiscitis (ISD) is a rare but potentially devastating condition in hemodialysis (HD) patients. Reports are limited especially in patients receiving high‐flux HD and hemodiafiltration (HDF). In a retrospective analysis, 13 patients on our maintenance high‐flux HD/HDF program were identified as having has infective spondylodiscitis over a 10‐year period (1997–2006), an incidence of approximately 1 episode every 215 patient‐years. The incidence was around 3 times higher in patients dialyzing with tunnelled central venous catheters (TCVC) than in those with arteriovenous fistulae. Affected patients were elderly (mean age 70 years) and had multiple comorbidities. Access problems, particularly TCVC infection, were common in the months preceding it's onset. Tunnelled central venous catheter removal during these episodes did not necessarily prevent it. Diagnosis was based on a history of back pain, raised C‐reactive protein, positive blood cultures, and characteristic magnetic resonance findings. Many patients were apyrexial and had normal white cell counts. In our patients on high‐flux HD/hemodiafiltration, its incidence appears comparable to that in conventional HD settings. No patients had infection with waterborne organisms. Blood cultures were positive in 77%. Gram‐positive organisms predominated, particularly Staphylococcus aureus. The major route of infection was hematogenous, with the most likely source the venous access. All received antibiotics for 6 to 12 weeks or until death. Only 2 patients underwent surgical drainage. Mortality was high (46%) and predicted by the development of complications, and by pre‐existing cardiovascular comorbidity. Prevention, using strategies to reduce the prevalence of bacteremia, including limiting the use of TCVC, should be an overriding aim.  相似文献   
922.
Adenine is naturally selected as the main energy carrier from among two types of purines. C. Duve mentions that the inevitability of adenosine triphosphate (ATP) is still a mystery. We examined the databases of DNA, RNA, and codon in order to clarify whether guanosine triphosphate (GTP) is mainly used for information storage in nucleic acids, because the adenine-uracil pair with a weaker connection would be dropped out relatively among the information carrier candidates due to natural selection. This paper presents a simple hypothesis that the relatively lower rates of adenine (A) and uracil (U) than the rates of guanine (G) and cytosine (C) observed in the RNAs for a lot of species cause redundant monomers of ATP and uridine triphosphate (UTP) outside nucleic acids, which become energy carriers. ATP runoff from RNA resembles the joker (or remaining unmatched queen) in the card game of Old Maid. The other redundant monomers of UTP might become polysaccharide generators. Actual frequencies of G and C in the RNAs of hyper-thermophiles are more than double those of A and U. A-U pairs are also fewer in number than G-C pairs in microorganisms such as yeast. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   
923.
After data mining National Aeronautics and Space Administration (NASA) independent verification and validation (IV&V) data, we offer (a) an early life cycle predictor for project issue frequency and severity; (b) an IV&V task selector (that used the predictor to find the appropriate IV&V tasks); and (c) pruning heuristics describing what tasks to ignore, if the budget cannot accommodate all selected tasks. In ten-way cross-validation experiments, the predictor performs very well indeed: the average f-measure for predicting four classes of issue severity was over 0.9. This predictor is built using public-domain data and software. To the best of our knowledge, this is the first reproducible report of a predictor for issue frequency and severity that can be applied early in the life cycle. This research was conducted at West Virginia University and the NASA IV&V Facility under NASA subcontract project 100005549, task 5e, award 1002193r. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise, does not constitute or imply its endorsement by the United States Government. See for an earlier draft.  相似文献   
924.
This communication describes a functioning model that permits access to an electronic health record across a small number of providers resident in an Australian regional setting. Design criteria designated that provider access rights were to be assignable, revokable, transportable, and informable.  相似文献   
925.
ABSTRACT: Yuzu (Citrus junos Tanaka) has been used as a traditional medicine in Japan. We investigated in vitro anti-inflammatory effects of limonene from yuzu peel on human eosinophilic leukemia HL-60 clone 15 cells. To examine anti-inflammatory effects of limonene on the cells, we measured the level of reactive oxygen species (ROS), monocyte chemoattractant protein-1 (MCP-1), nuclear factor (NF) kappa B, and p38 mitogen-activated protein kinase (MAPK). We found that low concentration of limonene (7.34 mmol/L) inhibited the production of ROS for eotaxin-stimulated HL-60 clone 15 cells. 14.68 mmol/L concentration of limonene diminished MCP-1 production via NF-kappa B activation comparable to the addition of the proteasomal inhibitor MG132. In addition, it inhibited cell chemotaxis in a p38 MAPK dependent manner similar to the adding of SB203580. These results suggest that limonene may have potential anti-inflammatory efficacy for the treatment of bronchial asthma by inhibiting cytokines, ROS production, and inactivating eosinophil migration.  相似文献   
926.
An expert system has been developed to predict the degree of tactile comfort during the application of cosmetic foundation. A tribometer using compliant silicone-rubber surfaces was developed to perform 4 sliding tests and an oscillating test. From the tests for 20 different samples, 11 feature quantities were identified. The values of the feature quantities were used as the inputs to an artificial neural network, and the scores of tactile sensations were obtained as the outputs. The neural network, after supervised learning, could predict 5 types of emotional tactile comfort with high accuracy.  相似文献   
927.
ABSTRACT: BACKGROUND: Frustrated phagocytosis has been stated as an important factor in the initiation of an inflammatory response after fibre exposure. The length of fibrous structures has been linked to the potential of fibres to induce adverse health effects for at least 40 years. However, we only recently reported for the first time the threshold length for fibre-induced inflammation in the pleural space and we implicated frustrated phagocytosis in the pro-inflammatory effects of long fibres. This study extends the examination of the threshold value for frustrated phagocytosis using well-defined length classes of silver nanowires (AgNW) ranging from 3--28 mum and describes in detail the morphology of frustrated phagocytosis using a novel technique and also describes compartmentalisation of fibres in the pleural space. METHODS: A novel technique, backscatter scanning electron microscopy (BSE) was used to study frustrated phagocytosis since it provides high-contrast detection of nanowires, allowing clear discrimination between the nanofibres and other cellular features. A human monocyte-derived macrophage cell line THP-1 was used to investigate cell-nanowire interaction in vitro and the parietal pleura, the site of fibre retention after inhalation exposure was chosen to visualise the cell- fibre interaction in vivo after direct pleural installation of AgNWs. RESULTS: The length cut-off value for frustrated phagocytosis differs in vitro and in vivo. While in vitro frustrated phagocytosis could be observed with fibres [GREATER-THAN OR EQUAL TO]14 mum, in vivo studies showed incomplete uptake at a fibre length of [GREATER-THAN OR EQUAL TO]10 mum. Recently we showed that inflammation in the pleural space after intrapleural injection of the same nanofibre panel occurs at a length of [GREATER-THAN OR EQUAL TO]5 mum. This onset of inflammation does not correlate with the onset of frustrated phagocytosis as shown in this study, leading to the conclusion that intermediate length fibres fully enclosed within macrophages as well as frustrated phagocytosis are associated with a pro-inflammatory state in the pleural space. We further showed that fibres compartmentalise in the mesothelial cells at the parietal pleura as well as in inflammatory cells in the pleural space. CONCLUSION: BSE is a useful way to clearly distinguish between fibres that are, or are not, membrane-bounded. Using this method we were able to show differences in the threshold length at which frustrated phagocytosis occurred between in vitro and in vivo models. Visualising nanowires in the pleura demonstrated at least 2 compartments -- in leukocyte aggregations and in the mesothelium - which may have consequences for long term pathology in the pleural space including mesothelioma.  相似文献   
928.
The nature of the adsorbed species on Cu-ZSM-5 (Cu-Z), Cu-Mordenite (Cu-M), and Cu-Y-zeolite (Cu-Y) was investigated by means of temperature programmed desorption (TPD). When dinitrogen monoxide (N2O) came into contact with Cu-zeolites above 573 K, the decomposition of N2O occurred accompanied by the formation of adsorbed oxygen species and adsorbed nitrogen oxide species. In the TPD runs, three O2 desorption peaks appeared at temperatures of 623, 673, and 753 K and were named -, β-, and γ-peaks, respectively. The O2 desorption at the - and γ-peaks became quickly saturated after contacting N2O at 598 K, while the amount of O2 desorbed at the β-peak increased with time, not reaching a constant level until 120 min of exposure. The activity for the decomposition of N2O decreased with the accumulation of β-oxygen over the catalyst. The rate of N2O decomposition depended upon the nature and amount of the copper zeolite catalysts available, as determined by the formation of - and/or β-oxygen.  相似文献   
929.
Several different sets of weighting functions are, or have been, in routine use in colour-measurement systems employed in industry to represent the same pairings of illuminant and observer. Exactly the same inputs to different weight-sets purporting to represent the same pairing give, often significantly, different outputs (e. g. colour-difference reports), leading to confusion, arguments between suppliers and their customers, and loss of faith in the capabilities of systems. The extent of variation between weight-sets is exemplified by those employed, at some time, by some of the major system suppliers to represent TL84. The practical effect of these variations is examined and a recommendation is made to use the weight-sets in ASTM E308-96. The relevant content of E308-96 is summarised and means of determining whether E308-96 weights are installed in a system are given. Tables of E308-96 weighting functions for CIE illuminants A, D65 and F11 (TL84) are appended.  相似文献   
930.
Spark plasma sintering (SPS) has been performed for 5 min at 1500°C and 30 MPa using submicrometer-sized Al2O3/ZrO2(2Y) composite powders in the Al2O3-rich region. Dense ZrO2-toughened Al2O3 (ZTA) ceramics show excellent mechanical strength; the strength of 1620 MPa is achieved in the ZTA with 50 mol% ZrO2. The grain size of Al2O3 in ZTA decreases from 1.5 to 0.6 m with increased ZrO2 content. Almost all the ZrO2 grains (0.3 m) are located in the boundaries of the Al2O3 grains. Mechanical properties are discussed, with an emphasis on the relation between t-/m-ZrO2 ratios and microstructures of ZTA.  相似文献   
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