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291.
Tested whether perfectionism dimensions uniquely predict chronic unipolar and chronic bipolar symptoms. A sample of 121 patients and former patients (mean age 46.1 yrs) completed the Multidimensional Perfectionism Scale, the General Behavior Inventory, and the Beck Depression Inventory. The results confirm that the perfectionism dimensions are related to chronicity of depression symptoms. Whereas self-oriented perfectionism was uniquely associated only with chronic unipolar symptoms, both socially prescribed and other-oriented perfectionism were uniquely associated with chronic bipolar symptoms. Importantly, these relationships remained significant after controlling for the effects of concurrent state depression. Finally, only socially prescribed perfectionism was uniquely associated with state depression. The results provide support for the position that perfectionism dimensions are important in both chronic. and state depression symptoms, but the perfectionism dimensions may differ in terms of their degree of association with various facets of depressive phenomena. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
292.
While a major response to the drinking-driving problem has been to increase penalties for drinking-driving offences, the impact of sentence severity on the driving behaviour of offenders (specific deterrence) remains unclear. In this research, relationships between aspects of sentence severity (licensedeterrence) suspension, fine, jail term, assignment to probation, or temporary absence programmes) and postconviction accidents and drinking-driving convictions were examined, while controlling statistically for demographic and previous driving record factors. License suspensions were consistently associated with traffic safety benefits. However, increasing severity of other aspects of punishment seemed unrelated to outcome or was associated with increased traffic safety problems. As well, important differences between first, second, and multiple offenders were observed, which may be related to the impact of different aspects of sentence severity on driving behaviour.  相似文献   
293.
We previously demonstrated that anesthetics and non-immobilizers suppress learning and memory in rats. In the training portion of the test, rats received a light plus a footshock and learned to associate the two, as evidenced by subsequent potentiation of the response (jumping) to light plus a noise (fear-potentiated startle). However, anesthetics and nonimmobilizers also decreased the response of animals receiving footshocks during training, which suggests that the reduction in fear-potentiated startle might reflect analgesia, rather than an impairment of learning and memory. Furthermore, although we previously demonstrated that the nonimmobilizer 2,3-dichlorohexafluorocyclobutane (2N) could completely abolish learning, we did not demonstrate the minimal dose required. In the present study, we eliminated analgesia as a confounding factor by training rats breathing desflurane and 2N with footshock intensities that produced responses at least equal to those produced in control animals. Both desflurane and 2N suppressed learning at 0.2 times the minimum alveolar anesthetic concentration (MAC) or the MAC predicted from lipid solubility, despite the increased footshock intensity. This partial pressure of desflurane equals that previously shown to suppress learning at lower footshock intensities. We conclude that suppression of learning and memory by desflurane and 2N does not result from decreased sensitivity to the unconditioned stimulus (the footshock) and that the potency of 2N is consistent with its lipophilicity. IMPLICATIONS: General anesthesia eliminates recall of intraoperative events, including pain. Using an animal model, we refuted the hypothesis that lack of recall results from the analgesia (i.e., the reduced response to painful stimuli produced by inhaled drugs) rather than from a direct effect on learning.  相似文献   
294.
The mechanism by which n-alkanols produce anesthesia and the characteristics relevant to those mechanisms (e.g., lipid solubilities versus potencies) remain unknown. Accordingly, we determined potencies (minimum alveolar anesthetic concentration [MAC]) and solubilities of normal methanol, ethanol, butanol, hexanol, and octanol. We also determined the additivity of these alkanols with a conventional anesthetic (desflurane) and the additivity of methanol with butanol. Finally, we determined whether alkanol metabolism influences alkanol potencies. MAC for methanol, ethanol, butanol, hexanol, and octanol (0.00200, 0.000989, 0.000133, 0.0000214, and 0.00000117 atm, respectively) increased with an increasing solubility in olive oil (olive oil/gas partition coefficients 48.6, 108, 1,650, 11,600, and 93,500, respectively) and octanol (octanol/gas partition coefficients 163, 1,150, 22,900, 135,000, and 4,140,000) to give a product of MAC x solubility for olive oil approximately 10 times less (values of 0.10-0.25) than that expected from the Meyer-Overton hypothesis (compared with conventional inhaled anesthetics). There was less deviation for octanol, but the results were more variable. Inhibition of methanol and butanol metabolism by 4-methylpyrazole did not alter MAC. Methanol, ethanol, butanol, hexanol, and octanol had approximately additive anesthetic effects with desflurane, with some small but statistically significant deviations both above and below additivity. In the presence of 0.5 MAC of desflurane, we needed to add 0.4-0.6 MAC of each alkanol to inhibit the movement of 50% of the rats in response to noxious stimulation. Similarly, the effects of methanol and butanol were additive (with each other). The saline/gas partition coefficient for each alkanol was high (3700, 2650, 1400, 900, and 709 for methanol through octanol), which indicates high polarity. We conclude that the potent anesthetic effects of normal alkanols may result from an affinity to both polar and nonpolar phases. Our finding of additivity of alkanols with each other is consistent with a common mechanism of action. Similarly, the finding of additivity or slight deviations from additivity for alkanols with desflurane is consistent with mechanisms of action that have much in common.  相似文献   
295.
Risk and promotive effects were investigated as predictors of persistent serious delinquency in male participants of the Pittsburgh Youth Study (R. Loeber, D. P. Farrington, M. Stouthamer-Loeber, & W. B. van Kammen, 1998), living in different neighborhoods. Participants were studied over ages 13-19 years for the oldest sample and 7-13 years for the youngest sample. Risk and promotive effects were studied in 6 domains: child behavior, child attitudes, school and leisure activities, peer behaviors, family functioning, and demographics. Regression models improved when promotive effects were included with risk effects in predicting persistent serious delinquency. Disadvantaged neighborhoods, compared with better neighborhoods, had a higher prevalence of risk effects and a lower prevalence of promotive effects. However, predictive relations between risk and promotive effects and persistent serious delinquency were linear and similar across neighborhood socioeconomic status. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
296.
This study examined the lifetime prevalence of trauma exposure and posttraumatic stress disorder (PTSD) and their demographic, diagnostic, and trauma-related correlates in a clinical cohort of 426 patients with a first psychiatric admission for psychosis. The prevalence of trauma exposure was 68.5%. Female gender and substance abuse were risk factors for trauma exposure. The prevalence of PTSD was 14.3% in the full sample and 26.5% in those with trauma exposure. PTSD was less prevalent in patients with bipolar disorder and schizophrenia and was twice as common in women. Other significant risk factors were younger age and trauma exposure that was repeated and ongoing or that involved childhood victimization. The findings highlight the importance of systematically ascertaining trauma histories in patients with psychotic disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
297.
Lake Analyzer is a numerical code coupled with supporting visualization tools for determining indices of mixing and stratification that are critical to the biogeochemical cycles of lakes and reservoirs. Stability indices, including Lake Number, Wedderburn Number, Schmidt Stability, and thermocline depth are calculated according to established literature definitions and returned to the user in a time series format. The program was created for the analysis of high-frequency data collected from instrumented lake buoys, in support of the emerging field of aquatic sensor network science. Available outputs for the Lake Analyzer program are: water temperature (error-checked and/or down-sampled), wind speed (error-checked and/or down-sampled), metalimnion extent (top and bottom), thermocline depth, friction velocity, Lake Number, Wedderburn Number, Schmidt Stability, mode-1 vertical seiche period, and Brunt-Väisälä buoyancy frequency. Secondary outputs for several of these indices delineate the parent thermocline depth (seasonal thermocline) from the shallower secondary or diurnal thermocline. Lake Analyzer provides a program suite and best practices for the comparison of mixing and stratification indices in lakes across gradients of climate, hydro-physiography, and time, and enables a more detailed understanding of the resulting biogeochemical transformations at different spatial and temporal scales.  相似文献   
298.
The nature of the defects that form on the surface of InP during the zinc diffusion process has been investigated. They are typically found to be composed of a crystalline inclusion and an associated indium droplet. SEM/EDX, X-ray and TEM studies show that the crystalline inclusions are composed of Zn3P2, which has an epitaxial relationship to the InP surface. A mechanism for the formation of the defects is proposed and a new all metallic diffusion source is described. This source, which is based on Zn-Ga-In-Cd mixtures, enables the defects to be largely eliminated. On sabbatical leave from Soreq Nuclear Research Centre Yavne, 70600, Israel  相似文献   
299.
Hepatitis B virus (HBV) infection persists as a major global health problem despite the availability of HBV vaccines for disease prevention. However, vaccination rates remains low in some regions of the world, driving the need for novel strategies to minimise infections and prevent disease progression. Thus, understanding of perturbed molecular signaling events during early phases of HBV infection is required. Phosphosignaling is known to be involved in the HBV infection processes, yet systems-level changes in phosphosignaling pathways in the host during infection remain unclear. To this end, we performed phosphoproteome profiling on HBV-infected HepG2-NTCP cells. Our results showed that HBV infection drastically altered the host phosphoproteome and its associated proteins, including kinases. Computational analysis of this phosphoproteome revealed dysregulation of the pathways involved in immune responses, cell cycle processes, and RNA processing during HBV infection. Kinase Substrate Enrichment Analysis (KSEA) identified the dysregulated activities of important kinases, including those from CMGC (CDK, MAPK, GSK, and CLK), AGC (protein kinase A, G, and C), and TK (Tyrosine Kinase) families. Of note, the inhibition of CLKs significantly reduced HBV infection in HepG2-NTCP cells. In all, our study unravelled the aberrated phosphosignaling pathways and the associated kinases, presenting potential entry points for developing novel therapeutic strategies for HBV treatment.  相似文献   
300.
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