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81.
Recent findings indicate that neonatal injury results in decreased spinal plasticity in adult subjects (E. E. Young, K. M. Baumbauer, A. E. Elliot, & R. L. Joynes, 2007). Previous research has shown that acute manipulations of pain processing (i.e., administration of formalin, carrageenan, capsaicin) result in a loss of spinal behavioral plasticity (A. R. Ferguson, E. D. Crown, & J. W. Grau, 2006). Moreover, neonatal injury results in a lasting reduction in adult spinally mediated plasticity resembling the deficit seen following acute manipulations in adults (E. E. Young et al., 2007). The present study was designed to determine whether the effects of neonatal injury could be prevented by lidocaine administration during the initial healing period. Subjects (injured or uninjured) received lidocaine or saline on 1 of 4 administration schedules (preinjury only, postinjury only, for 24 hr postsurgery, or for 72 hr postsurgery). Results demonstrated that lidocaine administration did not prevent the hypersensitivity and reduced spinal plasticity associated with neonatal injury. This suggests that (a) the mechanisms underlying neonatal injury are independent of peripheral input in the initial healing period and (b) lidocaine is ineffective at preventing long-term spinal plasticity changes following neonatal injury. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
The study was a randomized placebo-controlled trial testing whether fluoxetine selectively enhances cessation for smokers with a history of depression. Euthymic smokers with (H+, n = 109) or without (H-, n = 138) a history of major depression received 60 mg fluoxetine or placebo plus group behavioral quit-smoking treatment for 12 weeks. Fluoxetine initially enhanced cessation for H+ smokers (p = .02) but subsequently impaired cessation regardless of depressive history. Six months after quit date, fluoxetine-treated participants were 3.3 times more likely to be smoking (p = .02). Further research is warranted to determine why high-dose fluoxetine produces continuing effects that oppose tobacco abstinence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Children often overestimate their contribution to collaborative activities. Across 2 studies, the authors investigated whether this memory bias supports internalization of the actions of others in the context of joint exchanges. After taking turns with (high collaborative condition; Studies 1 and 2) or working independently of (low collaborative condition; Study 2) an adult experimenter to create a series of novel toys, children's agent memory and reconstruction ability were assessed. Children in the high collaborative condition but not the low collaborative condition systematically overclaimed the actions of their social partner, more frequently reporting having completed steps performed by the experimenter than vice versa. This "I did it" bias was related to learning performance: high collaborative children outperformed low collaborative children both during an immediate reconstruction task and 4 months later, and the strength of the bias predicted children's independent toy-building accuracy. It is argued that the "I did it" bias may emerge as part of a general process of learning from others and is supported by a common framework for representing self-actions and other actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
The rising costs of new psychological tests, increased frequency of test revisions, and difficulty receiving authorization and reimbursement from managed care companies make it increasingly difficult for practitioners to provide the best standard of care to clients when conducting psychological and neuropsychological assessments. Practitioners, especially those in low-income and rural areas, may struggle with handling these practical realities while maintaining ethical standards in conducting psychological assessment. Suggestions for how to manage practical challenges faced by practitioners who provide psychological assessments, such as selecting tests when authorization or reimbursement by a third-party payer is restricted or denied, purchasing psychological tests on a budget, and providing assessments with a limited number of qualified staff are discussed. The authors also provide recommendations for the future prevention of these challenges through work with test developers, test publishing corporations, third-party payers, political action groups, and the psychology profession itself. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
85.
We perform optical frequency metrology of an iodine-stabilized He-Ne laser using a mode-locked Ti:sapphire laser frequency comb that is stabilized using quantum interference of photocurrents in a semiconductor. Using this technique, we demonstrate carrier-envelope offset frequency fluctuations of less than 5 mHz using a 1 s gate time. With the resulting stable frequency comb, we measure the optical frequency of the iodine transition [127I2 R(127) 11-5 i component] to be 473 612 214 712.96 ± 0.66 kHz, well within the uncertainty of the CIPM recommended value. The stability of the quantum interference technique is high enough such that it does not limit the measurements.  相似文献   
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This study examined the fuel use and design of an improved woodburning cookstove (plancha), in comparison to traditional cooking over an open woodfire. These cookstoves had been randomly introduced into population households in the Guatemalan Highlands that had previously used open woodfires. This research consisted of: (1) a 12-household Kitchen Performance Test (KPT) over a 4-day period and (2) single-day participant observation in five households. The KPT monitored fuel consumption and the number, age, and gender of people who were cooked for, while the participant observation was used to form a complete understanding of fuel use patterns and to examine the influence of stove condition and cooking behavior. In spite of fairly low variability in the fuel use data (coefficients of variation of about 0.34) the KPT did not show statistically significant differences in fuel use between the two cooking methods. It is possible that increased study power through a larger sample size may have resulted in a statistically significant difference in favor of the plancha, but it is doubtful that the size of the effect would be of any practical significance. Thus, although other studies have shown that the plancha is extremely effective in reducing indoor air pollution in the study area, the KPT did not indicate that it offered any benefits with respect to fuel use. Practical and experimental recommendations for future cookstove efficiency studies are presented, with directions for continued work in this area.  相似文献   
89.
Detection of light in the eye underlies image-forming vision, but also regulates adaptive responses in physiology and behavior. Typically these adaptive responses do not involve image-forming vision, but depend on a relatively absolute measure of brightness (nonimage-forming irradiance detection). The goal of this study was to further understand how image-forming vision and nonimage-forming irradiance detection contribute to the effects of light on behavior. Three light dependent behaviors were assessed in wild-type, Rpe65-/- and rd1 mice. In Rpe65-/- mice, nonimage-forming irradiance detection is severely attenuated, but rod based visual acuity is relatively preserved. In rd1 mice visual acuity is nonrecordable, but nonimage-forming responses are less severely attenuated than Rpe65-/-. Positive masking, an image-forming vision dependent increase in wheel running, was absent in rd1 and restricted to higher irradiances in Rpe65-/-. Negative masking, a suppression of wheel running sensitivity with nonimage-forming irradiance detection input, was increased in rd1, but reduced in Rpe65-/- mice. By contrast, light aversion, an avoidance of brightly lit areas, was abolished in both Rpe65-/- and rd1. This shows that image-forming vision is not sufficient for light aversion, suggesting nonimage-forming irradiance detection motivates this behavior. Further, the differing effects of disease suggest that negative masking and light aversion are distinct responses with specialized nonimage-forming irradiance detection pathways. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
90.
The development of speech perception during the 1st year reflects increasing attunement to native language features, but the mechanisms underlying this development are not completely understood. One previous study linked reductions in nonnative speech discrimination to performance on nonlinguistic tasks, whereas other studies have shown associations between speech perception and vocabulary growth. The present study examined relationships among these abilities in 11-month-old infants using a conditioned head-turn test of native and nonnative speech sound discrimination, nonlinguistic object-retrieval tasks requiring attention and inhibitory control, and the MacArthur-Bates Communicative Development Inventory (L. Fenson et al., 1993). Native speech discrimination was positively linked to receptive vocabulary size but not to the cognitive control tasks, whereas nonnative speech discrimination was negatively linked to cognitive control scores but not to vocabulary size. Speech discrimination, vocabulary size, and cognitive control scores were not associated with more general cognitive measures. These results suggest specific relationships between domain-general inhibitory control processes and the ability to ignore variation in speech that is irrelevant to the native language and between the development of native language speech perception and vocabulary. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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