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21.
RC Smith KN Wills D Antelman H Perlman LN Truong K Krasinski K Walsh 《Canadian Metallurgical Quarterly》1997,96(6):1899-1905
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100 directors from randomly selected, federally funded community mental health centers and 70 coordinators from university-based, master's-level clinical training programs were surveyed by mail. A 5-part questionnaire sought information regarding (a) relative amount of time spent by master's-level clinicians performing 10 specified professional responsibilities, including psychodiagnostics, psychotherapy and counseling, research, administration, and consultation, or relative time spent at them in training; (b) the same estimates projected 10 yrs into the future; (c) differences in the groups' ratings of master's-level clinician's competency for the same 10 responsibilities; (d) perceived relative importance of each responsibility for the clinicians; and (e) estimates of importance 10 yrs hence. Results are based on return rates of 33% for center directors and 60% for program coordinators and are presented in both between- and within-groups comparisons. Master's-level clinicians were seen as competent professionals having a continuing role in mental health service delivery. Implications for training, provision of service, and degree recognition are considered. (12 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
24.
AO Colson JH Perlman A Jinsi-Parimoo DR Nussenzveig R Osman MC Gershengorn 《Canadian Metallurgical Quarterly》1998,54(6):968-978
We have studied the role of a highly conserved tryptophan and other aromatic residues of the thyrotropin-releasing hormone (TRH) receptor (TRH-R) that are predicted by computer modeling to form a hydrophobic cluster between transmembrane helix (TM)5 and TM6. The affinity of a mutant TRH-R, in which Trp279 was substituted by alanine (W279A TRH-R), for most tested agonists was higher than that of wild-type (WT) TRH-R, whereas its affinity for inverse agonists was diminished, suggesting that W279A TRH-R is constitutively active. We found that W279A TRH-R exhibited 3.9-fold more signaling activity than WT TRH-R in the absence of agonist. This increased basal activity was inhibited by the inverse agonist midazolam, confirming that the mutant receptor is constitutively active. Computer-simulated models of the unoccupied WT TRH-R, the TRH-occupied WT TRH-R, and various TRH-R mutants predict that a hydrophobic cluster of residues, including Trp279 (TM6), Tyr282, and Phe199 (TM5), constrains the receptor in an inactive conformation. In support of this model, we found that substitution of Phe199 by alanine or of Tyr282 by alanine or phenylalanine, but not of Tyr200 (by alanine or phenylalanine), resulted in a constitutively active receptor. We propose that a hydrophobic cluster including residues in TM5 and TM6 constrains the TRH-R in an inactive conformation via interhelical interactions. Disruption of these constraints by TRH binding or by mutation leads to changes in the relative positions of TM5 and TM6 and to the formation of an active form of TRH-R. 相似文献
25.
In an extension of research by N. S. Endler et al (see record 1979-26949-001), citations in 10 introductory psychology textbooks were used as an index of the eminence of psychologists in the US, UK, and Canada. The 10 most prominent psychologists were Freud, Skinner, Piaget, C. Rogers, Pavlov, S. Schachter, A. Bandura, E. Erikson, H. Harlow, and N. Miller. Results are compared with those using the Social Sciences Citation Index. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
26.
OBJECTIVE: To compare patients with knee osteoarthritis (OA) who have and do not have back pain, and evaluate the prevalence, characteristics, and consequences of back pain among knee OA patients. METHODS: During a 3-year period, consecutive patients attending an outpatient rheumatology clinic were evaluated for the presence of back pain, and 368 were found to have OA of the knee. Clinical status was evaluated by the Clinical Health Assessment Questionnaire, radiographs, and joint examinations. RESULTS: Back pain was present in 54.6% of patients with OA of the knee. Almost every clinical status measure was worse among those reporting back pain, including Health Assessment Questionnaire (HAQ) disability, pain, global severity, fatigue, and psychological status. Back pain was more common in women and the obese, but was not associated with age, marital status, formal education, smoking history, or knee radiographic scores. In multivariate analyses the strongest correlates of back pain in knee OA patients were anxiety, night pain, HAQ disability, and global severity. CONCLUSION: Back pain is prevalent among OA clinic patients, more common than in rheumatoid arthritis or population studies, is linked to body mass index, and is associated with clinically significant increases in pain and other measures of clinical distress. 相似文献
27.
This study investigated the ability to deceive in participants with autism, mental retardation ( MR ), and normal development. The authors used S. Hala, M. Chandler, and A. S. Fritz's (see record, 78:20899) procedures, in which children deceive by creating false trails or by erasing all trails and lying about the true location of a hidden object. Participants with autism and those with MR did not differ in their ability to use a deceptive method to manipulate the behavior of another person. Participants with autism were significantly less able than participants with MR to understand that they manipulated the beliefs of another person by predicting the outcome of their deceptive act. The normal group outperformed the group with autism but not the group with MR on both parts of the task. Different possible interpretations of the results are discussed, including a deficit in theory of mind and a deficit in executive control functions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
28.
High-content screening and profiling of drug activity in an automated centrosome-duplication assay 总被引:4,自引:0,他引:4
Perlman ZE Mitchison TJ Mayer TU 《Chembiochem : a European journal of chemical biology》2005,6(1):145-151
Maintenance of centrosome number is essential for cell-cycle progression and genomic stability, but investigation of this regulation has been limited by assay difficulty. We present a fully automated image-based centrosome-duplication assay that is accurate and robust enough for both careful cell-biology studies and high-throughput screening, and employ this assay in a series of chemical-genetic studies. We observe that a simple cytometric profiling strategy, which is based on organelle size, groups compounds with similar mechanisms of action; this suggests a simple strategy for excluding compounds that undesirably target such activities as protein synthesis and microtubule dynamics. Screening a library of compounds of known activity, we found unexpected effects on centrosome duplication by a number of drugs, most notably isoform-specific protein kinase C inhibitors and retinoic acid receptor agonists. From a 16 320-member library of uncharacterized small molecules, we identified five potent centrosome-duplication inhibitors that do not target microtubule dynamics or protein synthesis. The analysis methodology reported here is directly relevant to studies of centrosome regulation in a variety of systems and is adaptable to a wide range of other biological problems. 相似文献
29.
Nurit Argov-Argaman 《Journal of dairy science》2019,102(3):2783-2795
Milk fat globule (MFG) size ranges over 3 orders of magnitude, from less than 200 nm to over 15 µm. The significance of MFG size derives from its tight association with its lipidome and proteome. More specifically, small MFG have relatively higher content of membrane compared with large globules, and this membrane exerts diverse positive health effects, as reported in human and animal studies. In addition, MFG size has industrial significance, as it affects the physicochemical and sensory characteristics of dairy products. Studies on the size regulation of MFG are scarce, mainly because various confounders indirectly affect MFG size. Because MFG size is determined before and during its secretion from mammary epithelial cells, studies on the size regulation of its precursors, the intracellular lipid droplets (LD), have been used as a proxy for understanding the mechanisms controlling MFG size. In this review, we provide evidence for 2 distinct mechanisms regulating LD size in mammary epithelial cells: co-regulation of fat content and triglyceride-synthesis capacity of the cells, and fusion between LD. The latter is controlled by the membrane's polar lipid composition and involves mitochondrial enzymes. Accordingly, this review also discusses MFG size regulation in the in vivo metabolic context, as MFG morphometric features are often modulated under conditions that involve animals' altered energy status. 相似文献
30.
Significant Enhancement of Proton Transport in Bioinspired Peptide Fibrils by Single Acidic or Basic Amino Acid Mutation 下载免费PDF全文
Bioinspired materials are extremely suitable for the development of biocompatible and environmentally friendly functional materials. Peptide‐based assemblies are remarkably attractive for such tasks, since they provide a simple way to fuse together functional and structural protein motifs in artificial materials. Motivated by this idea, it is shown here that the introduction of a single acidic, or basic, amino acid into the side chain of a heptameric self‐assembling peptide increases proton conduction in the resulting fibers by two orders of magnitude. This self‐doping effect is much more pronounced than the effect induced by the peptide's acidic and basic termini groups. Furthermore, the self‐doping process is found to be significantly more effective for acidic side chains than for basic ones due to both much more effective self‐doping process, resulting in an order of magnitude larger concentration of charge carriers for the acidic assemblies, and higher mobility of the formed charge carriers – almost threefolds in this case. This work facilitates the realization of unique bioinspired self‐assembled proton conducting materials that may find uses in the emerging bioprotonic technology. The presented design flexibility and, in particular, the ability to introduce both proton and proton holes further extend the usefulness of these materials. 相似文献