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71.
TM Libkuman J Griffith WM Wines MJ Dickel KG Doty 《Canadian Metallurgical Quarterly》1998,125(4):367-395
The authors conducted 9 experiments to test the hypothesis (S. Schwartz, 1975) that arousal influences the accessibility of information stored in memory. They investigated the relationship between arousal levels (as indexed by personality types) and the type of stimuli or cues presented during study or test. They predicted that low-arousal individuals (stable extraverted individuals in Experiments 1-3 and 5-9 and high-impulsive individuals in Experiment 4) would be influenced by semantic stimuli, whereas high-arousal individuals (neurotic introverted individuals in Experiments 1-3 and 5-9 and low-impulsive individuals in Experiment 4) would be influenced by physical (i.e., graphic, phonetic, or both) stimuli. They tested the arousal-accessibility hypothesis by using a variety of tasks including verbal discrimination, false recognition, cued recall, and paired associates. With the exception of the finding that stable extraverted participants performed better than neurotic introverted participants on an incidental associative-matching task (Experiment 3), the results from the verbal discrimination studies (1-5) did not support the hypothesis. In Experiment 6, the authors tested the hypothesis by using a false-recognition task. False alarms varied as a function of phonetic and semantic stimuli, but personality types were not differentially sensitive to the manipulation. The same was true for the cued-recall studies (Experiments 7 and 8); personality types were not differentially sensitive to the semantic and phonetic stimuli. Experiment 9 (paired-associate learning) was a replication of Schwartz's study. The authors found some support for the Schwartz hypothesis: Extraverted participants were adversely affected by semantic similarity. Overall, the findings did not provide much support for the arousal-accessibility hypothesis. 相似文献
72.
BD Coley RS Arellano LB Talner KG Baker T Peterson RF Mattrey 《Canadian Metallurgical Quarterly》1995,2(5):373-378
RATIONALE AND OBJECTIVES: Recent clinical work suggests that the Doppler resistive index (RI) may be useful in distinguishing obstructive from nonobstructive hydronephrosis. We evaluated the usefulness of the RI in a rabbit model of hydronephrosis. METHODS: Unilateral partial ureteral obstruction was produced in nine rabbits and complete obstruction in another nine. Three sham operations were performed, and these animals served as control subjects. The RI was measured in all kidneys before and 6 hr after surgery and on days 1, 4, and 7 postoperatively. The RI and the difference in RI (delta RI) between the obstructed and normal kidney were evaluated over time using a two-way analysis of variance. The intravenous urography and Whitaker tests served as gold standards. RESULTS: Hydronephrosis was observed on sonograms in all obstructed kidneys. Comparing groups, there was no significant difference in mean RI or delta RI between the three groups at any time point. Looking at individual groups over time, there was no significant change in mean delta RI, whereas the change in mean RI was significantly elevated above baseline only in the complete obstruction group at 6 hr (p = .002) and on days 4 (p = .008) and 7 (p = .006). In evaluating varying thresholds of RI and delta RI, we could not consistently discriminate between normal and obstructed kidneys. CONCLUSION: Although complete obstruction caused a significant increase in RI, partial obstruction failed to do so. RI and delta RI values proved to be insensitive predictors of obstruction in this rabbit model. 相似文献
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74.
JW Romano KG Williams RN Shurtliff C Ginocchio M Kaplan 《Canadian Metallurgical Quarterly》1997,26(1-2):15-28
The phosphorylation state of neurofilaments plays an important role in the control of cytoskeletal integrity, axonal transport, and axon diameter. Immunocytochemical analyses of spinal cord revealed axonal localization of all protein phosphatase subunits. To determine whether protein phosphatases associate with axonal neurofilaments, neurofilament proteins were isolated from bovine spinal cord white matter by gel filtration. approximately 15% of the total phosphorylase a phosphatase activity was present in the neurofilament fraction. The catalytic subunits of PP1 and PP2A, as well as the A and B alpha regulatory subunits of PP2A, were detected in the neurofilament fraction by immunoblotting, whereas PP2B and PP2C were found exclusively in the low molecular weight soluble fractions. PP1 and PP2A subunits could be partially dissociated from neurofilaments by high salt but not by phosphatase inhibitors, indicating that the interaction does not involve the catalytic site. In both neurofilament and soluble fractions, 75% of the phosphatase activity towards exogenous phosphorylase a could be attributed to PP2A, and the remainder to PP1 as shown with specific inhibitors. Neurofilament proteins were phosphorylated in vitro by associated protein kinases which appeared to include protein kinase A, calcium/calmodulin-dependent protein kinase, and heparin-sensitive and -insensitive cofactor-independent kinases. Dephosphorylation of phosphorylated neurofilament subunits was mainly (60%) catalyzed by associated PP2A, with PP1 contributing minor activity (10-20%). These studies suggest that neurofilament-associated PP1 and PP2A play an important role in the regulation of neurofilament phosphorylation. 相似文献
75.
76.
Growth of anaerobic bacteria in the AnaeroPack (Mitsubishi Gas Chemical America, Inc., New York, N.Y.) anaerobic atmosphere generation systems, both the AnaeroPack jar and pouch and the AnaeroPack in a GasPak jar were considered equivalent to or better than growth obtained in the corresponding GasPak jar or pouch system (Becton Dickinson Microbiology Systems, Cockeysville, Md.) for 89 (86%) of the 103 anaerobes tested. There were a total of 26 discrepancies after 48 h of incubation, with 16 discrepancies unresolved after 96 h of incubation. The AnaeroPack jar and pouch never failed to reduce the anaerobic indicator. The AnaeroPack systems are easy to use and performed at least as well as or better than the BBL GasPak systems for growth of anaerobic bacteria. 相似文献
77.
The feasibility of intragenerically characterizing bifidobacteria by a comparison of a short region within the recA gene was tested. An approximately 300 bp fragment of the recA gene was PCR-amplified from six species from the genus Bifidobacterium using primers directed to two universally conserved regions of the recA gene. A phylogenetic analysis of the sequenced recA products compared favorably to classification based on the 16S rRNA sequences of the species tested. To apply this rapid methodology to unknown human intestinal bifidobacteria, 46 isolates were randomly chosen from the feces of four subjects and initially characterized by RFLP analysis of a PCR-amplified region of their 16S RNA genes. From a representative of the dominant RFLP family in each of the subjects, the recA segment was PCR-amplified, sequenced and phylogenetically analyzed. All four isolates were found to be related to one another and to B. longum and B. infantis. These results illustrate that the recA gene may be useful for intrageneric phylogenetic analysis as well as for the identification of unknown fecal bifidobacteria. 相似文献
78.
JY Kang KG Yeoh KY Ho R Guan TP Lim SH Quak A Wee D Teo YW Ong 《Canadian Metallurgical Quarterly》1997,12(9-10):655-659
The aim of this study was to determine, first, whether racial differences exist in the seroprevalence of Helicobacter pylori infection in Singapore, and second, whether these differences correlate with racial differences in peptic ulcer frequency. A commercial serological test for immunoglobulin (Ig)G antibody to H. pylori which was 90% sensitive and 83% specific in our population was used to screen 403 adult blood donors of Chinese, Malay and Indian origin, aged between 15-60 years. Serum specimens from 84 paediatric patients admitted to the Paediatrics Department, National University of Singapore, with non-gastroenterological illnesses were also tested. In all three races, seroprevalence of H. pylori increased with age. Indians have the highest prevalence of infection followed by Chinese and Malays. Peptic ulcer prevalences are known to be highest in Chinese, followed by Indians and Malays. The Malays have the lowest prevalence of H. pylori and peptic ulcer among the three races in Singapore. Indians have a higher prevalence of H. pylori antibodies but a lower frequency of peptic ulcer than the Chinese. Racial differences in peptic ulcer frequency between Chinese and Indians are not explained by the prevalence of H. pylori infection; other environmental or genetic factors may be involved. 相似文献
79.
The products of cleavage of bovine factor Va by activated protein C (APC) in the presence and absence of phospholipid (25% phosphatidylserine, 75% phosphatidylcholine, PCPS) were evaluated using sedimentation velocity/equilibrium methods in the analytical ultracentrifuge and by immunoprecipitation using an antibody directed against the light chain of the factor Va molecule. The molecular weight and sedimentation coefficient of the associated heavy and light chains of factor Va, 173,000 (7.9 S) is reduced to 132,000 (7.1 S) by APC cleavage at Arg505 and Arg662. Complete cleavage of the factor Va heavy chain (with APC-PCPS) at Arg505, Arg662 and Arg306 results in a drastic change in the molecular weight observed for the product. Two products are resolved with sedimentation coefficients of 3.3 and 6.3 S with estimated molecular weights of 48,000 and 114,000, respectively. Immunoprecipitation studies showed that the products of factor Va cleavage at Arg505 and Arg662 (A1A2N.A2C.LC) are mostly noncovalently associated and consequently immunoprecipitated with an antibody directed against the light chain of the factor Va molecule. In contrast, for factor Va cleaved at Arg505, Arg662, and Arg306 the precipitated complex consisted of the A1 domain (residues 1-306) and the light chain (residues 1537-2183) of factor Va (A1.LC). The fragments corresponding to residues 307-505 (A2N) and 506-662 (A2C) are found in the supernatant. The combined mass of these two products (48,000) is similar to the estimated mass of the 3.3 S fragment estimated from sedimentation velocity/equilibrium studies; while the combined mass of the 1-306 + 1537-2183 products corresponds to 114,000, the estimated mass of the 6.3 S fragment. These data lead to the conclusion that cleavages at Arg306, Arg505, and Arg662 of the factor Va molecule resulted in the dissociation of the entire A2 domain as two noncovalently associated fragments (A2N.A2C). Enzyme kinetic and light scattering data suggest that the complete inactivation of the factor Va molecule involves not only cleavage at Arg306 but also the dissociation of the A2 domain. These data also suggest that the complete APC inactivation of the factor Va molecule is analogous to the spontaneous inactivation of factor VIIIa, which occurs via the dissociation of the A2 domain. 相似文献
80.
OBJECTIVE: To report the efficacy and outcomes of transcervical resection of the endometrium (TCRE) in treatment of menorrhagia. METHODS: 400 patients with menorrhagia due to fatigue causes who had failed in medical therapy and did not desire pregnancy and surgery underwent TCRE under hysteroresectoscope. Among them, 72 patients with submucous uterine myoma less than 5cm in diameter had their myoma resected simultaneously, 366 cases were followed up postoperatively for 3 months to 4 years. RESULTS: TCRE was performed successfully except 16 cases, giving a success rate of 95.6%. Three cases sustained uterine perforation. During follow-up, 146 cases (41.7%) became amenorrhea, 119 (34.0%) had only spotting. The remaining 85 (24.3%) had normal periods. 78.3% of the cases who previously had dysmenorrhea had relieved their pain. Long-term complications were recurrent abnormal uterine bleeding (22 cases 13 of them had a second operation), hematometra (5) and adenomyosis (4 cases). CONCLUSION: TCRE is an effective procedure in treating menorrhagia and small submucous uterine myoma. 相似文献