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91.
幽门螺杆菌感染的诊断方法,按检测原理不同可分为形态学检查、细菌培养、尿素酶依赖性试验、血清免疫学、基因分子生物学检测五大类。而按照检测创伤性的不同可分为侵入和非侵入检查两类。本文将对这些方法分类介绍评价。  相似文献   
92.
Three experiments using human participants varied the distribution of point‐gain reinforcers or point‐loss punishers in two‐alternative signal‐detection procedures. Experiment 1 varied the distribution of point‐gain reinforcers for correct responses (Group A) and point‐loss punishers for errors (Group B) across conditions. Response bias varied systematically as a function of the relative reinforcer or punisher frequencies. Experiment 2 arranged two conditions — one where an unequal ratio of reinforcement (5:1 or 1:5) was presented without punishment (R‐only), and another where the same reinforcer ratio was presented with an equal distribution of point‐loss punishers (R+P). Response bias was significantly greater in the R‐only condition than the R+P condition, supporting a subtractive model of punishment. Experiment 3 varied the distribution of point‐gain reinforcers for correct responses across four unequal reinforcer ratios (5:1, 2:1, 1:2, 1:5) both without (R‐only) and with (R+P) an equal distribution of point‐loss punishers for errors. Response bias varied systematically with changes in relative reinforcer frequency for both R‐only and R+P conditions, with 5 out of 8 participants showing increases in sensitivity estimates from R‐only to R+P conditions. Overall, the results indicated that punishers have similar but opposite effects to reinforcers in detection procedures and that combined reinforcer and punisher effects might be better modeled by a subtractive punishment model than an additive punishment model, consistent with research using concurrent‐schedule choice procedures.  相似文献   
93.
Gaze following allows individuals to detect the locus of attention of both conspecifics and other species. However, little is known about how this ability develops. We explored the emergence of bobwhite quail hatchlings’ ability to track human gaze by assessing their avoidance behavior in an open arena under five testing conditions: (1) a Direct Gaze condition, in which an experimenter looking down was positioned above one of two approach areas; (2) a Gaze Follow condition in which an experimenter, positioned equidistant between two approach areas, directed his/her gaze towards one of the areas; (3) a Masked Gaze Follow condition, in which the experimenter wore a mask during the Gaze Follow test; (4) a Deprived Face Experience condition, in which hatchlings were deprived of experience with human faces prior to the Gaze Follow test; and (5) a Control condition in which no experimenter was present during testing. Results revealed that hatchlings from the Direct Gaze condition preferred the non-gazed approach area at all ages tested. Hatchlings from the Gaze Follow condition preferred the non-gazed approach area at 48 and 72 h, but not at 24 h of age. In contrast, hatchlings from the Masked Gaze Follow, Deprived Face and Control conditions did not prefer either approach area at any age tested. These results indicate that experience with human faces plays a key role in the rapid emergence of gaze following behavior in bobwhite quail hatchlings.  相似文献   
94.
钟杰  谭洁清  匡海彦 《心理学报》2005,37(6):753-759
比较了高强迫症状(High obsessive compulsive symptom, HOC)和低强迫症状(Low obsessive compulsive symptom, LOC)被试对于不同类型词语(强迫症敏感词、情绪词和中性词)再认成绩和记忆信心的差异。结果发现,HOC组记忆保存量显著低于LOC组(p<0.05),表明HOC组对强迫症敏感词存在一定的偏好;通过对被试反应信心的检测和信号侦察论的应用,发现HOC组对中性词再认正误的判断觉察能力(d’值)低于LOC组(边缘显著:p=0.054);在正确反应信心上,被试类型和词语类型间存在交互作用,F(1,22)=4.60,p<0.05。本研究认为HOC组辨别能力的缺损可能导致其记忆信心方面的降低,这种假设还需要进一步的认知和脑功能研究来证实。  相似文献   
95.
In this study, we investigated the relationship between religious coping style and anxiety related to breast cancer and the use of mammography in a sample of African American women. We also assessed the relationship of breast cancer anxiety to related variables such as church affiliation and attendance, church teachings on health, and acceptance of those teachings.  相似文献   
96.
Online testing of infants by recording video with a webcam has the potential to improve the replicability of developmental studies by facilitating larger sample sizes and by allowing methods (including recruitment) to be specified in code. However, the recorded video still needs to be manually scored. This labour-intensive process puts downward pressure on sample sizes and requires subjective judgements that may not be reproducible in a different laboratory. Here we present the first fully automatic pipeline, using a face analysis software-as-a-service and a discriminant-analysis classifier to score infant videos acquired online. We compare human and machine performance for looking time and preferential looking paradigms; machine performance demonstrates a promising proof of principle for looking time and is above chance in classifying preferential looking. Additionally, we studied the characteristics of the video and the child that influenced automated scoring, so that future studies can acquire data that maximises the performance of automatic gaze coding and/or focus on improving automatic coding for particularly challenging data. We believe this technology has great promise for developmental science.  相似文献   
97.
The performance of 6 domestic hens on a visual acuity task was studied using a spatial discrete-trial conditional discrimination procedure. Gray stimuli and vertical square-wave gratings, ranging in spatial frequency from 1 to 10 cycles per millimeter, were presented in a descending and ascending series of probes. On each trial, either a grating or gray stimulus was presented. Only one spatial frequency of grating was presented during each session. Between probe sessions, training continued at the coarsest grating value. Stimulus discriminability, measured as values of log d, changed with changes in grating spatial frequency for both probe series. Fitted lines described the linear portion of the psychometric functions. Thresholds estimated from the lines generally ranged from four to six cycles per degree, with slightly greater estimates from data from the descending probe series. There were no systematic changes in response bias as a function of grating spatial frequency.  相似文献   
98.
We evaluated the effects of two health education teaching methods, a pamphlet based on a task-analyzed checklist and two professionally developed films, on the completeness, accuracy, and maintenance of testicular self-examinations (TSE). Subjects (N = 48) were videotaped while performing a TSE after training and at a follow-up visit. Direct observation of the tapes showed that checklist-based training resulted in more complete and longer TSEs (p < .05). Social validation ratings, however, suggested that physicians were unable to discriminate reliably the performances of subjects taught using the two methods. Accuracy of detection of simulated lesions on plastic models was also similar for the two groups. Adherence to TSE recommendations was high during the study, but declined across the follow-up period. Further study is needed to promote adherence to TSE and to document the effects of early detection on morbidity and mortality of testicular cancer.  相似文献   
99.
100.
Three experiments are reported in which two pigeons were trained to detect differences in stimulus duration under varying levels of absolute rate of reinforcement. Two red stimuli, differing in duration, were arranged probabilistically on the center key of a three-key chamber. On completion of the center-key duration, the center keylight was extinguished and the two side keys were illuminated white. Correct responses were left-key pecks following the shorter duration and right-key pecks following the longer duration. In Experiment 1, relative rate of reinforcement for correct responses was held constant and absolute rate of reinforcement was varied in seven conditions from continuous reinforcement to a variable-interval 90-second schedule. In Experiment 2, relative rate of reinforcement was manipulated across three different absolute rates of reinforcement (continuous reinforcement, variable-interval 15-second, and variable-interval 45-second). Stimulus discriminability was unaffected by changes in absolute or relative rates of reinforcement. Experiment 3 showed that discriminability was also unaffected by arranging the same consequences (three-second blackout) for unreinforced correct responses and errors.  相似文献   
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