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91.
Objective: To examine cardiovascular reactivity and recovery to laboratory stress among a naturalistic sample of individuals diagnosed with major depressive disorder (MDD) and healthy control participants. Prospective evidence suggests that MDD confers risk for cardiovascular disease equal to or greater than the risk associated with depressed mood. Enhanced cardiovascular reactivity has been proposed as a mechanism explaining increased risk, but data are inconsistent as to whether depressed individuals exhibit enhanced or attenuated reactivity. Further, few studies have examined appraisal and recovery differences. Design: Participants diagnosed with MDD (N = 25) and healthy control participants (N = 25) engaged in a cardiovascular reactivity protocol including 2 tasks, each followed by a brief recovery period. Main outcome measures: Blood pressure, heart rate, pre-ejection period, cardiac output and total peripheral resistance were assessed. Appraisals of tasks were assessed prior to each task. Results: Depressed participants exhibited significantly less systolic blood pressure, heart rate, and cardiac output reactivity during speech, less heart rate reactivity during mirror tracing, and less heart rate recovery after speech and mirror tracing than controls. Depressed participants appraised the tasks as more demanding, threatening, and stressful and reported being less able to cope than controls. Appraisals were related to heart rate reactivity, but appraisals did not mediate the relationship between depression group and reactivity. Conclusion: Impaired recovery rather than exaggerated cardiovascular reactivity may partially explain the increased prospective cardiovascular disease risk in depressed individuals. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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93.
The EUREFIC (European Reaction to Fire Classification) has produced many fire test data made available through a Data Converting System (DCS). DCS is a simple PC-based program which transfers data logger files into a standard fire test data format, given by FDMS (Fire Data Management System). DCS is also capable of transferring standard data files into data formats of common spreadsheets. The EUREFIC programme has made two models for assessing large-scale performance of test materials. These models are integrated into a PC program called CT (Cone Tools).  相似文献   
94.
Myosin solutions and suspensions have been monitored during heating at pH 6.0 by using dynamic rheological measurements. The storage modulus (G′), the loss modulus (G) and the phase angle (δ) all showed a marked dependence on ionic strength in the temperature range 25–75°C. The filamentous gels (ionic strength <0.34) displayed a temporary reduction in G′ at temperatures between 50 and 60°C, presumably due to denaturation in parts of the rod portion of the myosin molecule. In the same temperature region the concentration dependence of G′ changed by a power of 2. The loss modulus also showed a marked concentration dependence, while the phase angle varied with concentration primarily at low (<50°C) temperatures. For the final gels, heated to 75°C, only G′ indicated marked differences due to different protein concentrations and ionic strengths; all gels were almost completely elastic (δ?1°). Adenosine triphosphate was shown to have a pronounced temporary effect on the filamentous gel formed at low temperatures, i.e. on the gel with the highest concentration dependence, while pyrophosphate had no such effect. However, both adenosine triphosphate (or rather its hydrolysis product: adenosine diphosphate) and pyrophosphate appeared to have a small, lasting effect on the heat-gelling ability of myosin: the former a detrimental effect, the latter an improvement.  相似文献   
95.
Investigated the moderating effects of choice and preference of music on pain perception. 90 students (aged 17–35 yrs) initially rated and ranked 6 musical selections, from most-to-least preferred in a context unrelated to pain testing. In the experiment proper, Ss received 3 trials of finger-pressure pain of which the 1st and 3rd trial involved no-treatment. Following baseline, half of the Ss (Choice condition) were asked to rate and rank the previous 6 musical selections and the remaining Ss were not required to do so (No-Choice). One-third of Ss in each of these groups were assigned either their most-preferred, least-preferred or no music during trial 2. Ss receiving their preferred music reported greater control, expected pain reductions and actual pain reductions compared to groups receiving their least-preferred music or no music. While choice failed to interact with preference, expectancies, coping cognitions and the annoying and relaxing qualities of the music were moderate predictors of reported pain change. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
96.
Three studies assessed the relationship between language and the perception of emotion. The authors predicted and found that the accessibility of emotion words influenced participants' speed or accuracy in perceiving facial behaviors depicting emotion. Specifically, emotion words were either primed or temporarily made less accessible using a semantic satiation procedure. In Studies 1 and 2, participants were slower to categorize facial behaviors depicting emotion (i.e., a face depicting anger) after an emotion word (e.g., "anger") was satiated. In Study 3, participants were less accurate to categorize facial behaviors depicting emotion after an emotion word was satiated. The implications of these findings for a linguistically relative view of emotion perception are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
97.
The authors tested the hypotheses that unfair treatment and its attribution to race, physical appearance, and peer group were related to elevated ambulatory blood pressure (ABP). During 2 school days, 207 Black and White adolescents wore an ABP monitor and answered questions about mood, posture, location, and activity level at the time of the ABP assessment. At a separate session, in-clinic resting blood pressure and perceptions of unfair treatment were measured. Multilevel mixed models showed that unfair treatment and its attribution to race were not associated with ABP. However, adolescents who indicated that the primary reason for unfair treatment was their physical appearance had elevated ABP. Feeling unfairly treated because of physical appearance may impact blood pressure uniquely during the adolescent transition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
98.
The present study examined children's cognitive engagement with television as a function of the continuity of central or incidental content and whether this varied with age and clinical status. In Experiment 1, 9- to 11-year-old children's response times on a secondary task were slower the later a probe occurred in a sequence of central events, and response times predicted recall. Experiment 2 extended these results to 6- to 8-year-old children. Experiment 3 revealed that children with attention-deficit/hyperactivity disorder (ADHD) failed to show the pattern consistently observed for comparison children. The results support the hypothesis that typically developing children build a representation during viewing that reflects the causal structure of the televised story but that this skill is deficient in 4- to 9-year-old children with ADHD. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
99.
Although related to conventional carbon nanotubes in both shape and construction, fullerene nanowhiskers and fullerene nanotubes have received far less attention. A modified liquid-liquid interfacial precipitation technique is described to produce relatively uniform batches of [60]fullerene nanotubes in high yield. Transmission electron microscopy (TEM) and atomic force microscopy (AFM) reveal that the tubes possess approximately 100-nm inside diameters and 300-nm outside diameters. The [60]fullerene nanotubes degrade slowly at 180 degrees C, eventually collapsing into micron scale [60]fullerene discs and rods, as revealed by optical microscopy and AFM. Ultrasonic cavitation chops [60]fullerene nanotubes into smaller segments within seconds. Longer ultrasonic bathing leads to considerable structural damage in which the sidewalls rupture. Mechanical stress tests using an AFM microscope tip effectively dent and break [60]fullerene nanowhiskers, revealing a hollow interior.  相似文献   
100.
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