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41.
Explanatory style as a predictor of productivity and quitting among life insurance sales agents. 总被引:1,自引:0,他引:1
Tested the prediction of the reformulated learned helplessness model, which claims that the tendency to explain bad events by internal, stable, and global causes potentiates quitting when bad events are encountered. Two studies were conducted, using a total of 197 life insurance agents as Ss. Explanatory style, as measured by the Attributional Style Questionnaire (ASQ), correlated with and predicted the performance of the Ss. In a cross-sectional study, Ss scoring in the top half of the ASQ sold 37% more insurance in their 1st 2 yrs of service than those scoring in the bottom half. In a prospective 1-yr study of newly hired agents, Ss who scored in the top half of the ASQ when hired remained in their job at twice the rate and sold more insurance than those scoring in the bottom half of the ASQ. These 2 studies support the claim that a pessimistic explanatory style leads to poor productivity and quitting when bad events are experienced, and they extend the usefulness of the ASQ to the workplace. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
42.
KA Schulman M Buxton H Glick M Sculpher G Guzman J Kong M Backhouse J Mauskopf L Bell JM Eisenberg 《Canadian Metallurgical Quarterly》1996,12(4):698-713
We present the prospective economic evaluation that served as a secondary endpoint for the FIRST study, a randomized international multicenter trial of patients with severe congestive heart failure. Although the clinical results of this study were disappointing, we demonstrated the feasibility of incorporating prospective economic evaluation in phase III clinical trials. 相似文献
43.
N Neymark W Kiebert K Torfs L Davies P Fayers B Hillner R Gelber G Guyatt P Kind D Machin E Nord D Osoba D Revicki K Schulman K Simpson 《Canadian Metallurgical Quarterly》1998,34(9):1317-1333
In recent years, quality of life (QoL) and economic evaluations have become increasingly important as additional outcome measures in cancer clinical trials. However, both fields of research are relatively new and in need of finding solutions to a substantial number of specific methodological problems. This paper reports on the proceedings of a symposium aimed at summarising and discussing some of the most contentious methodological and statistical issues in QoL and economic evaluations. In addition, possible solutions are indicated and the most pertinent areas of research are identified. Issues specific to QoL evaluations that are addressed include clinically meaningful changes in QoL scores; how to analyse QoL data and to handle missing and censored data and integration of length of life and QoL outcomes. Issues specific to economic evaluations are the advantages and disadvantages of various outcome measures; statistical methods to analyse economic data and choice of decision criteria and analytical perspective. How to perform QoL and economic evaluations in large and simple trials and whether the gap between QoL and utility measures can be bridged are also discussed. 相似文献
44.
L. S. Schulman 《Journal of Superconductivity》1999,12(6):703-706
Experimental observations of quantum jumps suggest that one can associate a time scale shorter than the usual lifetime with quantum transitions. Two such scales are discussed here, and their relation to experiments and to other theoretical ideas is explored. 相似文献
45.
Large granules from barley starch were packed into a column and hydrolysed with α‐amylase by pumping a diluted enzyme solution through the starch bed. The enzyme was then trapped onto an ion‐exchanger and the dextrins that solubilised from the granules were collected and characterised. The size‐distribution of the solubilished dextrins ranged from degree of polymerisation (DP) 2—500. The linear and branched products originated from both the amylose and the amylopectin components. The rate of solubilisation and the composition of the solubilised dextrins from barley starch were very similar to those found for large wheat starch granules. 相似文献
46.
47.
H Schulman L Laufer E Kurzbert Z Cohen Y Hertzanu 《Canadian Metallurgical Quarterly》1998,8(8):1455-1456
A rare case of chronic intussusception is reported. Radiological investigation including ultrasound, CT and barium enema provided the correct diagnosis. Ultrasound revealed a solid mass near the transverse colon in the right lower abdomen. CT demonstrated the real nature of the solid mass as being the classical 'coiled spring' of intussusception. The barium enema was unsuccessful as an attempt at hydrostatic reduction, but confirmed the diagnosis by a 'crescent-shaped' filling defect in the ascending colon. The patient was discharged after an uneventful surgery and recovery. No organic lesion that precipitated the chronic intussusception was discovered at operation. Radiological findings, the typical clinical picture and adequate treatment are discussed. 相似文献
48.
49.
The effect of hydrogen on fermentation of lactate, pyruvate, fumarate, and succinate by resting rumen microorganisms has been investigated. Under an atmosphere of nitrogen, lactate was fermented to yield acetate as the major product (85 to 100 mole %) and propionate (0 to 17 mole %) and butyrate (0 to 3%) as secondary products. Under hydrogen, there was increased formation of both propionate and total volatile fatty acids. The amount of propionate increased 4 to 8 times and total volatile fatty acids 2.5 to 3.2 times. Propionate formation was proportional to the hydrogen concentration and reached a maximum at a partial pressure of hydrogen of .2 N/m2. With [2-carbon-14] lactate, propionate was formed via the dicarboxylic acid pathway under both nitrogen or hydrogen. Hydrogen did not affect significantly the fermentation of pyruvate or succinate. With fumarate under hydrogen, propionate and total volatile fatty acids increased 6.8 and 2 times while acetate was unchanged. The mechanism by which hydrogen exerts these effects is discussed in relation to the role of methanogenesis in the rumen. 相似文献
50.
We have studied the effects of zinc on the 51Cr survival of red blood cells (RBC) from patients with homozygous sickle cell anemia (SCA) using an animal model in which the RBC were transfused into specially prepared rats. The slope (lambdas) of a standard 51Cr RBC survival curve was used as a measure of the rate of RBC sequestration. The effects of intravenous zinc were of considerable therapeutic interest from the standpoint of setting guidelines for effective blood levels of zinc in patients. SCA RBC were transfused into rats whose plasma zinc levels had been raised 3-6 times above normal (300-600 mug/100 ml) by prior iv injection of zinc acetate; in three experiments the mean lambdas in zinc-treated animals breathing 15-16% oxygen was significantly lower (meaning lessened sequestration and greater survival) than saline-treated controls. A possible explanation for the requirement to lower ambient oxygen tension in order to see this zinc effect is discussed. We have further observed an increased mean lambdas for RBC from 10 SCA patients compared to 4 normal controls (0.134 vs 0.030; t = 2.8, p less than 0.01). The lambdas values are quite patient specific (4 patients studied; F = 18.2, P = 0.002). In vitro pretransfusion treatment of SCA RBC with 1.5 mM zinc resulted in a significant increase in hemoglobin oxygen affinity and a marked reduction in lambdas (0.073 vs 0.120; t = 4.5, p less than 0.01). The mean lambdas was not affected by in vitro 0.3 mM zinc treatment; this level did not change hemoglobin oxygen affinity. We conclude that systemic zinc therapy in the animal model described, at plasma levels only slightly higher than those presently obtained in patients, prolongs SCA RBC survival. This animal model is a sensitive measure of the sicklability of SCA RBC and is useful in the testing of in vitro and in vivo antisickling agents. 相似文献