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111.
112.
Many traditional ethnic cultural items are being endangered in China. Using the Dongba dance culture of the Naxi people as a case study, this paper seeks to analyze and interpret the endangerment of culture from an educational perspective, based on an analysis of the interaction between the cultural transmission mechanism of Dongba dance and the formal schooling of the Naxi people in Lijiang, China. By describing and comparing the traditional and current forms of Dongba dance transmission, the paper shows how the institution of formal education competes with older modes of cultural transmission, resulting in the endangerment of Dongba dance as a living cultural relic. So, in order to truly realize and improve the function of education in transmitting cultural heritage and to guarantee educational equity, we should prioritize sophisticated ethnic minority cultural items in the assessment and selection phases of education, grant them institutional cultural capital, and put greater effort into developing an appropriate school-based curriculum so that ethnic minority culture may be transmitted and inherited via formal schooling.  相似文献   
113.
Three soccer header types (shooting, clearing and passing) and two heading approaches (standing and jumping) were manipulated to quantify impact forces and neck muscle activity in elite female soccer players. The 15 participants were Division I intercollegiate soccer players. Impact forces were measured by a 15-sensor pressure array secured on the forehead. The electromyographic (EMG) activity of the left and right sternocleidomastoid and trapezius muscles was recorded using surface electrodes. Maximum impact forces and impulses as well as the EMG data were analysed with separate repeated-measures analyses of variance. Impact forces and impulses did not differ among the header types or approaches. Higher values were found for jumping versus standing headers in the mean normalized EMG for the right sternocleidomastoid. In addition, the integrated EMG was greater for the right sternocleidomastoid and right and left trapezius (P < 0.05). The sternocleidomastoid became active earlier than the trapezius and showed greater activity before ball contact. The trapezius became active just before ball contact and showed greater activity after ball contact. The increased muscle activity observed in the neck during the jumping approach appears to stabilize the connection between the head and body, thereby increasing the stability of the head-neck complex.  相似文献   
114.
The primary aim was to examine the criterion and construct validity and test–retest reliability of the Lifesource XL-18 pedometer (A&D Medical, Toronto, ON, Canada) for measuring steps under controlled and free-living activities. The influence of body mass index, waist size and walking speed on the criterion validity of XL-18 was also explored. Forty adults (35–74 years) performed a 6-min walk test in the controlled condition, and the criterion validity of XL-18 was assessed by comparing it to steps counted manually. Thirty-five adults participated in the free-living condition and the construct validity of XL-18 was assessed by comparing it to Yamax SW-200 (YAMAX Health & Sports, Inc., San Antonio, TX, USA). During the controlled condition, XL-18 did not significantly differ from criterion (P > 0.05) and no systematic error was found using Bland–Altman analysis. The accuracy of XL-18 decreased with slower walking speed (P = 0.001). During the free-living condition, Bland–Altman analysis revealed that XL-18 overestimated daily steps by 327 ± 118 than Yamax (P = 0.004). However, the absolute percent error (APE) (6.5 ± 0.58%) was still within an acceptable range. XL-18 did not differ statistically between pant pockets. XL-18 is suitable for measuring steps in controlled and free-living conditions. However, caution may be required when interpreting the steps recorded under slower speeds and free-living conditions.  相似文献   
115.
This study investigated whether haematological markers differ between young and masters marathon participants, running at similar performance levels. Nine young (31.89 ± 4.96 years) and eight masters (63.13 ± 4.61 years) runners participated. At five time points (pre-race through 54 h post-race), a complete blood cell count, basic metabolic panel and creatine kinase (CK) isoenzyme panel were assessed. Race performance was standardised using the World Masters Association Age Grading Performance Tables. Total CK levels were elevated for all participants at all time points post-race (P < 0.001). The CK-isoenzyme MB% was elevated across groups at 6, 30 and 54 h post-race (< 0.01, < 0.01 and < 0.05), with masters runners having a higher CK-MB% at 30 and 54 h (< 0.05, < 0.05). Total white blood cell and neutrophil counts were elevated through 6 h post-race (< 0.001), with higher levels found in younger runners (< 0.001). When considering all blood work, masters runners had a higher number of abnormal values at 6, 30 and 54 h post-race (< 0.05, < 0.01 and < 0.05). In conclusion, masters runners demonstrated sustained CK-MB elevation, which may suggest greater cardiac stress. However, future studies using additional cardiac markers should be completed to confirm these findings. In addition, masters runners showed an increased number of laboratory values outside normal range, indicating the body’s reduced capacity to respond to marathon running.  相似文献   
116.
An accurate measurement of force and biomechanical energy that people can impart through kicking is useful for kick-related sports training. Existing methods are indirect measurements or focus on force and not on the total energy of the kick. A kick test rig was designed, constructed and instrumented to measure the force and displacement of a vertical target subjected to kicking. The kick energy was calculated from the recorded force and displacement histories. The methodology for measurement of kick force and energy was validated by an open stance front kick test by 52 volunteers. The results showed that 67% of the participants could achieve an average energy above 100 J. An increasing trend of kick energy with increasing body weight of participant was observed. The participant’s gender had a strong influence on the kick energy, while training in martial arts does not appear to be a significant parameter. A probability analysis showed that one in one hundred adults will be able to kick with energies exceeding 215 J.  相似文献   
117.
The stiffness measuring method for bicycle frames is not standardized, leading to a wide variety of test setups; they differ in many aspects such as applied load, support constraints and frame deflection measurement. The aim of this paper is to draw attention to this problem and to quantify the perturbing, unwanted side effects that influence the stiffness measurement of the bicycle frame. This is illustrated by developing a multi-purpose rating test method for bicycle frame stiffness. The proposed test rig design considers different aspects which should be taken into account when measuring the bicycle frame stiffness. In the experimental setup, it is observed that the contribution of the test bench compliance led to 21% difference in the frame stiffness results; the influence due to the head, the tube-bearing type the corresponding preload resulted in up to 19% difference in the stiffness results between the lowest and highest stiffness values measured; hysteresis effects caused by pulleys are estimated to introduce errors up to 11%; and the influence due to the operator variability and sensor accuracy is estimated to be less than 3%.  相似文献   
118.
We develop and use a numerical model to investigate the window of opportunity of free kicks in association football. The planar multibody forward dynamics model comprises a two segment leg model with joint actuations, a football, a wall and the turf. Contact mechanics is defined to model the impact of the foot and the ball’s interaction with the different elements in the environment. The optimum kick is determined using the global optimization algorithm differential evolution, requiring millions of kick simulations. The sensitivity of various solutions to parameter perturbation is investigated. It is concluded that toe kicks are theoretically superior to instep kicks, but are difficult to perform reliably. The results also show that small perturbations in parameters can lead to embarrassingly failed kicks.  相似文献   
119.
The purpose of this research was to propose a method to acquire the three-dimensional movement of a roller skiing athlete utilizing a global positioning system (GPS), an atmospheric pressure sensor (APS), and an inertial measurement unit (IMU) to distinguish between diagonal skiing and double poling techniques. In this study, we developed a lightweight wearable sensor that was composed of a GPS, APS, and IMU. For the data collection, two national level athletes roller skied a 1700 m long course where the maximum difference in elevation was 5.3 m. The planar positions of the athletes were based on the longitudinal and latitudinal data provided by the GPS, and the altitude was calculated by the International barometric formula and Laplace transform from the APS. The longitudinal and latitudinal data acquired through GPS had errors within 2 m range at each point. The altitude of Laplace transform from the APS showed errors of less than 1 m at each point. The range of motion of pelvis from the IMU was 34.0?±?3.8° for diagonal skiing, which is wider than the 21.2?±?6.9° for double poling.  相似文献   
120.
The organization of individual sports into leagues has received little attention in research, but its practical relevance has increased. This article aims to elucidate the role of competitive balance and league design elements in a sports league with less spectator demand from a player perspective. The analysis focuses on the reformed German Golf League. Because this league is an amateur league with no payment for players and currently few spectators, a change in perspective is appropriate. The empirical results of the stated preference approach highlight the relevance of perceived competitive balance as well as several league characteristics for the players. The findings thus show that governing bodies of sports leagues should focus on both the development of an optimal league design and soft aspects to deliver attractive and challenging competition from a player’s perspective.  相似文献   
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