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91.
MA Weinstein MT Modic B Risius PM Duchesneau AJ Berlin 《Canadian Metallurgical Quarterly》1981,138(1):83-87
Altering the scintillation crystal configuration of a fixed-detector CT scanner increased the spatial resolution from 6.25 to 10 line pairs per centimeter. Sector scans of th orbit with this modified scanner showed the ophthalmic artery and superior ophthalmic vein and their branches and the intraorbital branches of the third, fifth, and sixth nerves, apparently seen with CT for the first time. 相似文献
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A Bizzi E Veneroni MT Tacconi AM Codegoni R Pagani M Cini S Garattini 《Canadian Metallurgical Quarterly》1980,5(3-4):227-240
Liquipron and Toprina, obtained by growing yeasts (Candida maltosa and Candida lipolytica) on n-hydrocarbons, were investigated to ascertain the biological significance and possible toxicological implications of their high content of uneven fatty acids (UFA). It was confirmed that the extent to which UFA accumulate in adipose tissue of rats fed the 2 products reflects only partially their UFA contents. The presence of UFA in rat tissues does not appear to alter intermediate metabolism. The capacity of liver mitochondria ot oxidize palmitic acid was similar in control and in Liquipron-treated rats. Palmitic acid and heptadecanoic acid did not compete for oxidation when mixed at concentrations which reflect their presence in the tissues of animals fed high levels of Liquipron. 相似文献
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Continuous analysis of a DNA restriction enzyme digest on a microfabricated device is demonstrated with minimal intervention and enhanced time resolution. A 62-base-pair fragment of dsDNA containing a KpnI site was used to demonstrate this process. A capillary was used to transfer sample from a single reaction mix to a microfabricated chip with parallel separation lanes. The 6-carboxyfluorescein-labeled DNA fragments were detected with a CCD camera as they separated in the lanes, which were filled with linear polyacrylamide. The products of the restriction enzyme digest were monitored for up to 60 min at an average sampling rate of 1 injection/46 s, with consecutive injections as short as 1 injection/14 s. The digest was injected directly into the chip, eliminating the need for any sample-handling steps after addition of the enzyme to the reaction mix. The effects of temperature and restriction enzyme concentration were briefly examined, as well. This work shows the potential of this method to provide valuable information about the process of restriction enzyme cleavage. 相似文献
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K Peris MT Onorati G Keller F Magrini P Donati L Muscardin H H?fler S Chimenti 《Canadian Metallurgical Quarterly》1997,137(3):356-360
OBJECTIVE: Thoracic injury remains a major source of morbidity and mortality in urban trauma centers. With the advent and increasing expertise in video assisted thoracic surgery, this modality has become an attractive alternative in the management of patients with thoracic injury. This report will review our experience with video assisted thoracic surgery at a level I trauma center and attempt to further delineate the indications for and timing of thoracoscopy in thoracic trauma. METHODS: We identified 16 patients who had undergone video assisted thoracic surgery following chest trauma between July 1991 and June 1994. There were 15 penetrating and one blunt trauma. All 16 patients were initially treated with tube thoracostomy. From 0-20 days post-injury, video assisted thoracic surgery was attempted with either diagnostic or therapeutic intentions. RESULTS: Twelve of the 16 patients (75%) had successful thoracoscopy. Three patients had diaphragmatic injury excluded and nine patients had successful evacuation of clotted hemothoraces. Evacuation of clotted hemothorax up to 7 days post-injury was safe and easily accomplished. Four patients (25%) had unsuccessful thoracoscopy and were converted to standard thoracotomy; failure was attributed to either suboptimal single lung ventilation or severe pleural inflammatory reaction. The only death in the entire group occurred 10 days after a thoracotomy for retained hemothorax. The median post-operative hospital stay following successful video assisted thoracic surgery was 3.5 days. CONCLUSIONS: Video assisted thoracic surgery can be utilized as an effective and safe method for the initial diagnostic evaluation and surgical management of stable patients with penetrating thoracic trauma. 相似文献
100.
SD Gettings RA Lordo KL Hintze DM Bagley PL Casterton M Chudkowski RD Curren JL Demetrulias LC Dipasquale LK Earl PI Feder CL Galli SM Glaza VC Gordon J Janus PJ Kurtz KD Marenus J Moral WJ Pape KJ Renskers LA Rheins MT Roddy MG Rozen JP Tedeschi J Zyracki 《Canadian Metallurgical Quarterly》1996,34(1):79-117
The CTFA Evaluation of Alternatives Program is an evaluation of the relationship between data from the Draize primary eye irritation test and comparable data from a selection of promising in vitro eye irritation tests. In Phase III, data from the Draize test and 41 in vitro endpoints on 25 representative surfactant-based personal care formulations were compared. As in Phase I and Phase II, regression modelling of the relationship between maximum average Draize score (MAS) and in vitro endpoint was the primary approach adopted for evaluating in vitro assay performance. The degree of confidence in prediction of MAS for a given in vitro endpoint is quantified in terms of the relative widths of prediction intervals constructed about the fitted regression curve. Prediction intervals reflect not only the error attributed to the model but also the material-specific components of variation in both the Draize and the in vitro assays. Among the in vitro assays selected for regression modeling in Phase III, the relationship between MAS and in vitro score was relatively well defined. The prediction bounds on MAS were most narrow for materials at the lower or upper end of the effective irritation range (MAS = 0-45), where variability in MAS was smallest. This, the confidence with which the MAS of surfactant-based formulations is predicted is greatest when MAS approaches zero or when MAS approaches 45 (no comment is made on prediction of MAS > 45 since extrapolation beyond the range of observed data is not possible). No single in vitro endpoint was found to exhibit relative superiority with regard to prediction of MAS. Variability associated with Draize test outcome (e.g. in MAS values) must be considered in any future comparisons of in vivo and in vitro test results if the purpose is to predict in vivo response using in vitro data. 相似文献