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11.
Early initiation of cigarette use is associated with higher levels of nicotine dependence. This paper provides a theory to explain this finding based on the neurotoxic effects of cigarettes on a developing system. The tobacco-induced neurotoxicity of adolescent cognitive development (TINACD) theory postulates that alterations in executive functioning, particularly evident under stressful or emotionally intense states, lead to higher levels of dependence. The model proposes that the neurotoxic effects of tobacco are most pronounced when smoking begins during early adolescence, a period of major neurodevelopment subserving inhibitory control.  相似文献   
12.
Behavior-state matching and synchrony in interactions were assessed in 48 depressed and nondepressed mother–infant dyads when the infants were 3 months old. Attentive/affective behavior states were coded for the infants and mothers on a negative to positive scale. The depressed mothers and their infants matched negative behavior states more often and positive behavior states less often than did the nondepressed dyads. The total percentage of time spent in matching behavior states was less for the depressed than for the nondepressed dyads. Cross-spectral analyses of the mothers' and the infants' behavior-state time series suggested only a trend for greater coherence or synchrony in the interactions of the nondepressed dyads. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
13.
Circulating cell-free DNA (cfDNA) is emerging as a potential tumor biomarker. CfDNA-based biomarkers may be applicable in tumors without an available non-invasive screening method among at-risk populations. Esophageal squamous cell carcinoma (ESCC) and residents of the Asian cancer belt are examples of those malignancies and populations. Previous epidemiological studies using cfDNA have pointed to the need for high volumes of good quality plasma (i.e., >1 mL plasma with 0 or 1 cycles of freeze-thaw) rather than archival serum, which is often the main available source of cfDNA in retrospective studies. Here, we have investigated the concordance of TP53 mutations in tumor tissue and cfDNA extracted from archival serum left-over from 42 cases and 39 matched controls (age, gender, residence) in a high-risk area of Northern Iran (Golestan). Deep sequencing of TP53 coding regions was complemented with a specialized variant caller (Needlestack). Overall, 23% to 31% of mutations were concordantly detected in tumor and serum cfDNA (based on two false discovery rate thresholds). Concordance was positively correlated with high cfDNA concentration, smoking history (p-value = 0.02) and mutations with a high potential of neoantigen formation (OR; 95%CI = 1.9 (1.11–3.29)), suggesting that tumor DNA release in the bloodstream might reflect the effects of immune and inflammatory context on tumor cell turnover. We identified TP53 mutations in five controls, one of whom was subsequently diagnosed with ESCC. Overall, the results showed that cfDNA mutations can be reliably identified by deep sequencing of archival serum, with a rate of success comparable to plasma. Nonetheless, 70% non-identifiable mutations among cancer patients and 12% mutation detection in controls are the main challenges in applying cfDNA to detect tumor-related variants when blindly targeting whole coding regions of the TP53 gene in ESCC.  相似文献   
14.
The objective of this study is to explore ways of determining the useful lengths of intervals in fuzzy time series. It is suggested that ratios, instead of equal lengths of intervals, can more properly represent the intervals among observations. Ratio-based lengths of intervals are, therefore, proposed to improve fuzzy time series forecasting. Algebraic growth data, such as enrollments and the stock index, and exponential growth data, such as inventory demand, are chosen as the forecasting targets, before forecasting based on the various lengths of intervals is performed. Furthermore, sensitivity analyses are also carried out for various percentiles. The ratio-based lengths of intervals are found to outperform the effective lengths of intervals, as well as the arbitrary ones in regard to the different statistical measures. The empirical analysis suggests that the ratio-based lengths of intervals can also be used to improve fuzzy time series forecasting.  相似文献   
15.
In 181 urban African Americans with Type 2 diabetes, medication adherence was assessed using a measure designed specifically for an urban, impoverished sociodemographic population. Hemoglobin A1c, blood pressure and cholesterol levels, medication-related beliefs, and depression were assessed. Seventy-four percent of the sample reported adherence to diabetes medication. Adherence, adjusted for age, was associated with lower hemoglobin A1c. The specific behaviors associated with poorer diabetes control were forgetting to take medications and running out of medications. Knowledge of blood glucose goals differed for adherers and nonadherers. Blood pressure and cholesterol medication adherence rates were not associated with actual levels of blood pressure or lipids, respectively. These data suggest that specific medication-taking behaviors are important to diabetes control and constitute logical targets for interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
16.
The extent to which sentence imagery elicits effects comparable to those produced by long narratives was investigated. Smokers imagined sentences with varying affective content and that either contained or were devoid of smoking cues. Physiological responses were monitored, and smokers rated their urges and affect. Startle responses were also collected as an index of negative affect processing. Smoking-cue sentences produced augmented urges and startle responding. Smoking material also elevated negative affect during imagery of positive affect sentences. The affect manipulation produced changes in self-reported affect and facial electromyography consistent with the affective valence of the sentences. This procedure is similar to narrative imagery in the manipulation of smoking urges and affect under laboratory conditions. Results support the hypothesis that smoking urges enhance negative affect processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
17.
Experiment 1 found that mixed-handedness, which is associated with increased interaction between the left and right cerebral hemispheres relative to strong right-handedness, was associated with an earlier offset of childhood amnesia. In Experiment 2, bilateral saccadic eye movements, which have been shown to enhance interhemispheric interaction, were also associated with an earlier offset of childhood amnesia. These results build upon a growing body of research indicating an interhemispheric basis for the retrieval of episodic memories. Moreover, the results of Experiment 2 suggest that interhemispheric interaction has its effect on the retrieval, not encoding, of episodic memories. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
18.
Auditory stimuli (a buzzer and rattle) and a tactile stimulus (a plastic filament) were repeatedly presented to 18 term and 18 preterm infants. Both groups initially responded to all stimuli with increased limb movements and heart rate acceleration. However, only the term infants responded to stimulus repetition by decreasing both cardiac and behavioral responses. In addition, they differentially responded to the 3 stimuli and showed response recovery in both systems. Since a behavioral response decrement was observed without a cardiac response decrement in the preterm group, a 2nd experiment was conducted. Heart rate change during the sucking activity of Exp II revealed an integration between autonomic and motor responsivity of preterm infants comparable to that of term newborns. The lack of cardiac–behavioral response integration during Exp I is discussed in the context of state differences between preterm and term infants as well as potential immaturity or some insult experienced by the preterm infants. The stimulus discrimination and habituation demands of Exp I may have overtaxed the preterm infants' ability to maintain response integration. (23 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
19.
Aggressive behavior between pairs of female or male zebra finches (Poephila guttata) was measured before, during, and after presentation of either a female or male finch (the stimulus) in an adjacent cage. Presentation of the stimuli led to marked increases in aggressive behavior for both sexes of Ss, such that presentation of a female stimulus caused an elevation in aggression in male pairs and presentation of a male stimulus caused an elevation in female pairs. These results are interpreted in the context of competition for mates in species, such as zebra finches, that have long-term monogamous pair bonds and biparental care. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
20.
Three experiments, with 64 Holtzman and 48 Wistar male rats, examined whether Ss would become tolerant, or sensitized, to morphine-induced hyperthermia and the directionality of the conditioned pyretic effects of morphine. Stress produced by temperature-assessment procedures affected Ss' pyretic response to morphine. Under conditions of high stress, Ss first showed diminished, and then enhanced, hyperthermic responding across repeated dosing with morphine sulfate (5 or 35 mg/kg, sc). The diminished hyperthermia can be attributed to habituation to high levels of assessment stress. Repeated morphine doses delivered under conditions of low stress produced only enhanced hyperthermic responding, indicating that Ss became sensitized to morphine's hyperthermic effects. There was little evidence that morphine supported conditioning of pyretic responses. The temperature-assessment stress that produced hyperthermia was mediated by opiate peptides, was blocked by naloxone, and enhanced the agonist effects of morphine. Implications for theories of drug conditioning and tolerance are discussed. (57 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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