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11.
Assessed the effect of parent weight (obese/nonobese parent) and parent control vs child self-control on the weight loss of 41 obese 8–12 yr olds over a 3-yr period. Children of nonobese parents had significantly greater decrease in relative weight after 1 yr, but not after 3 yrs, than children of obese parents. Locus of control was not related to treatment outcome over the 3 yrs. Results suggest that parent weight was related to weight loss, but not weight maintenance, in obese children. (9 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
12.
Discusses the operation of sexism in all areas of psychological research, from broad conceptual issues to narrow methodological concerns. It is argued that sexism, in the form of unexamined assumptions about the sexes and unequal treatment of males and females may enter psychological research at any phase of a research project. Three major types of barriers to sex-fair research are identified: excessive confidence in traditional methods of research, bias in explanatory systems, and inappropriate conceptualization and operationalization. A series of recommendations are offered to eliminate some of the most common forms of sexist bias in research and to stimulate critical discussion of practices within psychology that encourage or fail to challenge sexist bias. (103 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Recently a novel view on Kekulé valence structures (or resonance structures) was reported in which their standard geometrical representation was replaced by a numerical representation obtained by assigning π-electrons associated with CC double bonds to individual benzenoid rings. In the present article, we examine in more detail the partitioning of π-electrons to benzenoid rings for cata-condensed benzenoid hydrocarbons. For special families of cata-condensed benzenoids, we offer formulas which allow one to obtain the average π-electron ring content for individual benzenoid rings of polycyclic conjugated hydrocarbons. We also show that the average π-electron ring content for individual benzenoid rings can be calculated from Pauling bond orders without a need to examine all Kekulé resonance structures of a molecule.  相似文献   
14.
Crosslinked macroporous hydrophilic poly(glycidyl methacrylate-co-ethylene glycol dimethacrylate) [abbreviated poly(GMA-co-EGDMA)] with identical chemical structure (60% of glycidyl methacrylate) but with varied average pore sizes (from 30 to 560 nm), specific surface areas (from 13.2 to 106.0 m2/g), specific volumes (from 0.755 to 1.191 cm3/g) and particle sizes (<100 μm–630 μm) were synthesized via suspension polymerization. Modifications of poly(GMA-co-EGDMA) with various diamines (1,2-diaminoethane, 1,4-diaminobutane, 1,6-diaminohexane and 1,8-diaminooctane), 2-fluoroethylamine, glutaraldehyde and cyanuric chloride were carried out. The influence of the interaction between Candida antarctica lipase B (Cal-B) and various carriers during immobilization on the loading and hydrolytic activity (hydrolysis of para-nitrophenyl acetate) of the immobilized Cal-B were studied. Immobilization of Cal-B was performed at different temperatures and pH values. Cal-B immobilized at 30 °C and pH 6.8 was leading to increased activities. Purely physical adsorption between enzyme and copolymer was observed on carriers in which amine or fluorine groups were introduced into the carrier structure by modification with various diamines or 2-fluoroethylamine. As a consequence enzyme loading and activity decreases. In contrary, modification of the poly(GMA-co-EGDMA) with glutaraldehyde and cyanuric chloride results in a covalent connection between enzyme and carrier. The obtained results show a significant increase in Cal-B activity. The influence of the amount of glutaraldehyde and cyanuric chloride used for modification was screened. Increasing the amount of glutaraldehyde or cyanuric chloride used for modification resulted in an increase of the enzyme loading. Consequently, higher amount of glutaraldehyde used led to a higher fraction of the enzyme molecules that are covalently connected on to the carrier. As the amount of glutaraldehyde or cyanuric chloride used for modifications increases, activity of immobilized C. antarctica lipase B primarily increases, showing the highest value for 0.66% and 0.050% w/w, respectively, and subsequently decreases. We could show that Cal-B immobilized on epoxy-containing copolymer modified with glutaraldehyde and cyanuric chloride performs higher activity than free enzyme powder.  相似文献   
15.
Fragile X-associated tremor/ataxia syndrome (FXTAS) develops in a subset of fragile X premutation carriers and involves gait ataxia, action tremor, Parkinsonism, peripheral neuropathy, autonomic disorders, and cognitive impairment. The study was designed to define the nature of cognitive deficits affecting male premutation carriers with and without FXTAS. A sample of 109 men underwent motor, cognitive, genetic, and neurologic testing, as well as brain magnetic resonance imaging. Subjects were classified into 3 groups: (a) asymptomatic premutation carriers, (b) premutation carriers with FXTAS, and (c) normal controls. Men with FXTAS performed worse than controls on mental status, intelligence, executive cognitive functioning (ECF), working memory, remote recall of information, declarative learning and memory, information processing speed, and temporal sequencing, as well as 1 measure of visuospatial functioning. Language and verbal comprehension were spared. Asymptomatic carriers performed worse than controls on ECF and declarative learning and memory. This comprehensive examination of cognitive impairment in male premutation carriers suggests that FXTAS involves substantial executive impairment and diffuse deficits in other cognitive functions. Longitudinal research currently underway will provide insight into the progression of the disorder. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
Analyzed the effects of family variables (e.g., family size, family weight composition, parental weight) on child weight loss in a series of family-based, behaviorally oriented weight control programs for children from 102 families. Results show that the amount of relative weight change was related to initial treatment success, the number of children in the family, and the gender of the child. Children who were more successful lost more weight initially, had fewer siblings, and were female. It is suggested that family size may interact with treatment to determine weight change, possibly by reducing the amount of time a parent has to spend promoting behavior change or the effectiveness of parents in managing their children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
Confirmatory factor analysis (CFA) and structural equation modeling (SEM) were used to study the organization of executive functions in older adults. The four primary goals were to examine (a) whether executive functions were supported by one versus multiple underlying factors, (b) which underlying skill(s) predicted performance on complex executive function tasks, (c) whether performance on analogous verbal and nonverbal tasks was supported by separable underlying skills, and (d) how patterns of performance generally compared with those of young adults. A sample of 100 older adults completed 10 tasks, each designed to engage one of three control processes: mental set shifting (Shifting), information updating or monitoring (Updating), and inhibition of prepotent responses (Inhibition). CFA identified robust Shifting and Updating factors, but the Inhibition factor failed to emerge, and there was no evidence for verbal and nonverbal factors. SEM showed that Updating was the best predictor of performance on each of the complex tasks the authors assessed (the Tower of Hanoi and the Wisconsin Card Sort). Results are discussed in terms of insight for theories of cognitive aging and executive function. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
A 4-yr-old male's knowledge of 40 dinosaurs was elicited from 2 tasks. The data gathered from these knowledge-production protocols were used to map 2 interrelated semantic networks of dinosaurs, viewed as concept nodes connected by links. The 2 mappings corresponded to 2 sets of dinosaurs (20 each), partitioned on the basis of external criteria: mother's subjective judgment of the S's knowledge of each dinosaur and the frequency of mention in the S's dinosaur books. Comparisons of the structure of the 2 mappings were based on 3 attributes: (a) number of links, (b) strength of links, and (c) the internal cohesion of the network in terms of higher-order groupings and specific patterns of interlinkages. The validity of the differential structures of the 2 mappings was verified by the corresponding differential memory performance. The better structured set of dinosaurs was more easily remembered and retained by the S over a year than the less structured set of dinosaurs. (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
20.
Fragile X syndrome, the most common inherited cause of mental retardation, is caused by an abnormal gene on the bottom end of the X chromosome. Discovered and sequenced in 1991, it is called the Fragile X Mental Retardation-1 (FMR-1) gene. Mutations in the FMR-1 gene include small expansions with a CGG (a specific sequence of the nucleotides) repetitive sequence that repeats from 50 to 200 times (the premutation) and the full mutation that involves a CGG repeat sequence that is greater than 200. In the full mutation, the FMR-1 gene is usually methylated, turning off the gene so that no protein is produced. Mutations within the FMR- I gene can cause a spectrum of learning difficulties ranging from mild problems to severe mental retardation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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