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991.
SF Stinson DP Ryan S Hertweck JD Hardy SY Hwang-Kow CG Loosli 《Canadian Metallurgical Quarterly》1976,100(3):147-153
Pulmonary epithelial cell destruction in mice infected with PR8-A influenza virus has been studied with light and electron microscopy and enzyme histochemistry, and correlated with pulmonary surfactant activity. All epithelial cell types were infected by the virus, resulting in destruction, pneumonitis, and atelectasis by seven to ten days. Pulmonary surfactant activity decreased progressively following onset of infection, and was minimal by seven to ten days. Before types 1 and 2 alveolar pneumocytes regenerated, the regenerating bronchial cells grew peripherally into some of the denuded alveolar ducts and alveoli to form epithelial nodules. Eventually the types 1 and 2 pneumocytes regenerated to cover the alveolar surfaces that were not invaded by bronchial epithelium. This regeneration was associated with increased surfactant activity in the postinfluenzal lesions, suggesting that the type 2 pneumocytes are a source of surfactant. 相似文献
992.
993.
We observed an interstitial deletion of the long arm of chromosome 6 occurring as the sole anomaly in a benign fibrocystic disease of the breast, confirming its nonrandom occurrence in this type of condition, and we discuss the possible meaning of this observation. 相似文献
994.
BJ Amsel H De Raedt IE Rodrigus L Haenen P Druwé A Vorlat CG Colpaert AC Moulijn 《Canadian Metallurgical Quarterly》1996,62(1):267-269
Severe heart failure in acute rheumatic myocarditis is rare. It may be rapidly reversible with treatment, so maximal medical treatment and, if necessary, mechanical support should be given before heart transplantation is considered. 相似文献
995.
996.
Formoterol administered by a dry-powder (DP) capsule inhaler was compared with a pressurized metered-dose inhaler (pMDI) with regard to bronchodilating and systemic effects. The study used a double-blind, crossover, double-dummy technique. Twelve patients with moderate reversible asthma in a stable phase were examined on two separate study days, and the inhalers were given in randomized order. After baseline measurements, increasing doses of formoterol were given at intervals of 75 min. FEV1 and heart rate and tremor measurements were repeated after each dose, and the doses were 12 + 12 + 24 + 48 micrograms, giving a total dose of 96 micrograms. The peak expiratory flow rate (PEFR) was recorded in the morning before the first dose, after the last dose, and then repeatedly at home until 19 h after the last dose. There was an equal increase in ventilatory capacity at each dose level, independent of inhaler device. Repeated PEFR measurements after the last dose did not reveal any differences in duration of effect. There was a slight but statistically significant increase in heart rate and tremor after the highest doses of the DP formulation compared to the pMDI. These systemic effects can probably be explained by the reduced oral deposition of the aerosol caused by using a spacer. This study indicates that the DP and pMDI formulations of formoterol are equipotent in bronchodilation. 相似文献
997.
998.
999.
FM Muggia X Wu D Spicer S Groshen S Jeffers CG Leichman L Leichman KK Chan 《Canadian Metallurgical Quarterly》1996,2(9):1461-1467
UFT is an oral preparation combining the 5-fluorouracil (FU) prodrug tegafur (FT) and uracil (U) in a 1:4 ratio, which is commercially available in Japan for the treatment of breast and gastrointestinal cancers. We sought to determine the tolerance of daily oral UFT and to relate this tolerance to the pharmacokinetics of FT and/or the derived FU, while exploring the possibility of circadian FU kinetics contributing to the results. A 28-day schedule followed by 2 weeks rest was began at the initial level of 300 mg/m2/day administered either at 8 a.m. or at 6 p.m. At the following level, 400 mg/m2/day patients were randomly assigned to a split-dose administration or to the above single, timed dose administration. Intolerance to single dosing was clearly demonstrated, and only the split dosing was advanced to 500 mg/m2/day. When this level proved too toxic, 400 mg/m2 was studied further on a 7 a.m., 3 p.m., and 11 p.m. (every 8 h) schedule. Pharmacology was determined on selected patients. In the single dose administration, areas under the curves of FU were higher following p.m. dosing, although substantial interpatient variation was present. Toxicities (diarrhea and neutropenia) were more severe in patients receiving the drug in single daily doses. We conclude that the kinetics of FT are saturable, with disproportionate increases in area under the curve (and toxicities) as dose levels are increased. With divided dosing, tolerance improves. UFT at a dose of 400 mg/m2/day administered as three divided doses (every 8 h) is suitable for Phase II studies, although toxicity requiring cessation of drug administration prior to completion of 28-day cycles will occur in some patients. 相似文献
1000.
M Kallergi MA Gavrielides L He CG Berman JJ Kim RA Clark 《Canadian Metallurgical Quarterly》1998,5(10):670-679
RATIONALE AND OBJECTIVES: The authors developed and evaluated a method for the simulation of calcification clusters based on the guidelines of the Breast Imaging Reporting and Data System of the American College of Radiology. They aimed to reproduce accurately the relative and absolute size, shape, location, number, and intensity of real calcifications associated with both benign and malignant disease. MATERIALS AND METHODS: Thirty calcification clusters were simulated by using the proposed model and were superimposed on real, negative mammograms digitized at 30 microns and 16 bits per pixel. The accuracy of the simulation was evaluated by three radiologists in a blinded study. RESULTS: No statistically significant difference was observed in the observers' evaluation of the simulated clusters and the real clusters. The observers' classification of the cluster types seemed to be a good approximation of the intended types from the simulation design. CONCLUSION: This model can provide simulated calcification clusters with well-defined morphologic, distributional, and contrast characteristics for a variety of applications in digital mammography. 相似文献