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911.
The study has been undertaken as number of sickle cell patients in Chhattisgarh tribal population is 23.7 %. The Co enzyme Q10 is a strong antioxidant and energy producing compound. The patients were divided into three groups group A homozygous (SS), group B heterozygous (AS) and group C controls for TBARS study. The age group is 10–55 years and 200 mg of CoQ10 was given to A and B groups. The hematological parameters, C reactive protein as well as RBC TBARS level were performed by usual and standard techniques. The results were obtained as 25.37 % increased RBC level in group A and 23.24 % in group B. The increased hemoglobin level was observed as 16.73 % in group A and 10.7 % in group B. In case of WBC it was observed increased 24.38 % in group A and 12.0 % in group B. C-reactive protein was observed 7.8 times decreased in group A and 1.54 times in group B. The RBC TBARS level was also found decreased 48 % in group A and 51 % in group B as compared to group C. During the supplementation of coenzyme Q10 the pain caused by vaso-occlusive events has reduced. This significant increase in hematological parameters as well as decreased C-reactive protein and TBARS level suggest that the Q10 should be included in the diet of sickle cell patients.  相似文献   
912.
Children's experience of violence in China and Korea: a transcultural study   总被引:2,自引:0,他引:2  
Kim DH  Kim KI  Park YC  Zhang LD  Lu MK  Li D 《Child abuse & neglect》2000,24(9):1163-1173
OBJECTIVE: There were two aims: First, to compare children's rates of being battered in home, by peers, and by teachers among students between China and Korea, and second, to identify particular risk factors for such violence. METHODS: Children in grades four through six in Shanghai (238 cases) and Yanji (245 cases) in China and Seoul (248 cases) and Kimpo (241 cases) in Korea were surveyed by questionnaire method. They were asked to complete the Straus' Conflict Tactics Scale and their frequencies in the three situations respectively, and other demographic items. RESULTS: Family violence during the last 1 year was experienced in 70.6% (minor 42.2%; serious 22.6%) of the children in China and 68.9% (minor 9.4%; serious 51.3%) of those in Korea. Experience rates of violence by peers were 42.7% (minor 25.7%; serious 13.7%) in China and 26.0% (minor 11.5%; serious 14.3%) in Korea. Finally, rates of corporal punishment by teachers were 51.1% (minor 28.0%; serious 4.1%) in China and 62.0% (minor 8.8%; serious 43.8%) in Korea. The most important and common risk factor for violence in one situation was the presence of violence in another situation. CONCLUSIONS: The findings indicate that the differences in children's overall experience rates were not particularly striking. However, Korean children experienced more severe forms of violence from family members and from teachers. Findings of risk factors clearly imply that there are children vulnerable to violence from multiple sources.  相似文献   
913.
914.
915.
The aim of this study was to quantify movements of Super 12 rugby players in competition because information on elite rugby players' movements is unavailable. Players were categorized into forwards [front (n = 16) and back row (n = 15)] and backs [inside (n = 9) and outside backs (n = 7)] and their movements analysed by video-based time motion analysis. Movements were classified as rest (standing, walking and jogging) and work (striding, sprinting, static exertion, jumping, lifting or tackling). The total time, number and duration of individual activities were assessed, with differences between groups evaluated using independent sample t-tests (unequal variances), while differences between halves were assessed with paired sample t-tests. Forwards had 7:47?min:s (95% confidence limits: 6:39 to 8:55?min:s, P<0.01) more time in static exertion than backs, but backs spent 0:52 (0:34 to 1:09, P = 0.01) min:s more time sprinting than forwards, and had a 0.7 (0.3 to 1.2, P = 0.01) s longer duration of each sprint. Forwards spent 7:31 (5:55 to 9:08) min:s more time in work activities (P = 0.01) and had 2.1 (1.3 to 2.8) s longer work durations (P<0.01) than backs. The results indicate frequent short duration (<4?s) work efforts followed by moderate duration (<20?s) rest for forwards, and extended (>100?s) rest duration for backs. High-intensity efforts involved static exertion for forwards (mean?±?standard deviation frequency = 80?±?17) and sprinting for backs (27?±?9). In conclusion, after nearly a decade since becoming professional, elite rugby union is still characterized by highly intense, intermittent movement patterns and marked differences in the competition demands of forwards and backs.  相似文献   
916.
Abstract

In freestyle swimming the arm action is routinely quantified by stroke count and rate, yet no method is currently available for quantifying kick. In this study, we assessed the validity and reliability of inertial sensor technology (gyroscope) to assess kick count and rate. Twelve Paralympic swimmers completed a 100-m freestyle-swimming time-trial and freestyle kicking-only time-trial three times each in a season. An algorithm was developed to detect the up and down beat of individual kicks from the gyroscope trace. For comparative purposes, underwater video analysis provided the criterion measure. The standard error of the estimate (validity) for kick count, expressed as a coefficient of variation, was 5.9% (90% confidence interval 5.5 to 6.4) for swimming, and 0.6% (0.5 to 0.6) for kicking-only trials. The mean bias for kick count was ?1.7% (?2.4 to ?1.1) for swimming, and ?0.1% (?0.2 to ?0.1) for kicking-only trials. Correlations between the sensor and video for kick count were 0.96 (0.95 to 0.97) for swimming, and 1.00 (1.00 to 1.00) for kicking-only trials. The typical error of the measurement (reliability) between trials was approximately 4% for kick count and rate. The inertial sensors and associated software used generated sufficient validity and reliability estimates to quantify moderate to large changes in kick count and rate in freestyle swimming.  相似文献   
917.
Abstract

The contextual interference (CI) effect has been replicated many times since its first demonstration by Shea and Morgan (1979) in the motor learning domain (see Brady, 1998; Magill&;Hall, 1990). The CI effect is characterized by the observation that experiencing greater interference during acquisition is detrimental to immediate performance but enhances delayed performance as measured on retention or transfer tests. High CI is most often created by random practice in which the learning of multiple tasks occurs in a single training. In contrast, low CI is frequently created by using a blocked practice format in which all the practice trials of one task are completed before another task is introduced. One theoretical account that has been forwarded to account for the CI effect is labeled the action plan reconstruction hypothesis (Lee&;Magill, 1983, 1985). This position intimates that before a movement occurs an “action plan” must be prepared. In blocked practice, a previously prepared “action plan” is readily available from trial to trial, but it suffers from lack of attention on trials following initial retrieval from working memory. In random practice, however, each time a task must be executed a “reconstruction” of the action plan must be processed, because the interchange of information from trial to trial never allows the same information to remain in working memory for an extended amount of time. Presumably, the additional trial-to-trial preparation used by the random practice participant during practice results in a more resilient memory representation that better supports long-term recall efforts compared to their blocked practice counterparts.  相似文献   
918.
In order to pilot a shift towards greater use of collaborative learning in our higher education programs, the University of Hong Kong has invested in the development of a prototype technology-enhanced collaborative learning space. The space was created by retrofitting a vacant studio, turning it into an innovative classroom space in which collaborative learning is promoted and facilitated both through the provision of technology and by the physical layout of the room. We have used the space to pioneer collaborative learning both by holding professional development workshops for faculty in the room and also by helping academic staff to run experimental courses in the learning space. The opportunity to offer professional development and support for academic staff in this environment is particularly valuable as it ensures they do not simply deliver traditional didactic lectures in a space designed to promote interactive student learning and engagement. By using the space as a ‘student’ they are able to consider how they may use collaborative learning environments with their students. This paper describes use of the room for professional development of academic staff and also provides two examples of the use and evaluation of the room by faculty who used the room to teach experimental classes.  相似文献   
919.
Who borrows laptop computers in an academic health sciences library? Why do they choose to check out laptops? In a survey, laptop computer users responded that the laptops were used most frequently to do class-related work. Laptops were most often checked out because they could be taken to a quiet area of the library or to where the user had more room to work. The majority of such borrowers were satisfied or very satisfied with the laptops and the service from the library. The majority of those completing the survey were medical school students and graduate students. The circulation of laptop computers at this academic health sciences library is a very successful and popular program.  相似文献   
920.
Three hundred and seventy-nine participants were tested in the West Indies and in Canada, with the Rotter Locus of Control Scale and the Wolfgang Interpersonal Distance Test. The results indicated that West Indian adolescent students were more internally controlled than their Canadian counterparts. Also, overall, West Indian students showed more approach behavior toward significant interpersonal figures than Canadian students. In addition, no correlation was apparent between locus of control and social distance, suggesting that they are separate constructs. Implications of the findings for social adjustment of West Indian immigrants in Canada are discussed.  相似文献   
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