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71.
It is clear from the extant literature that gender inequities exist in a myriad of ways in science classrooms. Past research, however, has been conducted solely from researchers' observations and has neglected to investigate students' awareness of and reactions to their own experiences. Hence, this study focused on students' perceptions of gender differences in instructional activity and talk about that activity in physics and honors physics classes. Data analysis showed that although teachers may be unaware of gender inequities, students of both sexes are not unaware of such inequities. Females explained their fears of offering their opinions and participating in activities like labs and small-group or whole-class discussions. Differential language patterns were found for males and females, particularly when discussion was structured and rewarded for refutation. Explanations are offered for these disparities and suggestions are given for addressing gender bias in science classrooms. It has been well documented that science classrooms are not gender fair (Bazler & Simonis, 1991; Bianchini, 1993; Tobin, 1988). Teachers, texts, and the forms of instruction they perpetuate contribute to gender inequities in science instruction. For example, research tracing changes in science textbooks over time has shown that current texts have failed to eliminate barriers to women in science (Bianchini, 1993). Science textbooks are criticized for their unequal treatment of genders, with illustrations, photos, and texts of males far outnumbering those of females, despite the approximate 50/50 male/female ratio of our population (Bazler & Simonis, 1991). In addition to the proclivity of science textbooks to favor males, researchers speculate that the tendency for boys to achieve higher than girls in science may be a result of more opportunity to engage in academic tasks (Tobin & Garnett, 1987). Their behavior shows that teachers have differential expectations for students' responses in activities like teacher-led discussion. In teacher-led, whole-class discussion, boys are spoken to more frequently and are asked more higher-order questions (Becker, 1991; Hall & Sadler, 1982). Teachers in science classrooms elaborate more on males' responses than females' responses in large-group discussion of scientific concepts (Jones & Wheatley, 1990). © 1996 John Wiley & Sons, Inc.  相似文献   
72.
73.
The on-going Coronavirus disease(COVID-19)outbreak in China has become the world's leading health headline and is causing major panic and public concerns.On January 30,2020,the World Health Organization(WHO)declared that the new coronavirus outbreak is a public health emergency of international concern.1 The virus has already had a direct impact on more than 10 million people in the city of Wuhan and has reached other parts of China as well,posing a health threat of unknown magnitude globally.As of February 8,2020,WHO reported 34,886 confirmed cases of COVID-19 globally,with 34,589 of them occurring in China(including 6101 severe cases and 723 deaths).A total of 288 other confirmed cases(with 1 death)have been reported in 24 countries,including Japan,Australia,Germany,and United States.2 However,these daily estimates are expected to rise even higher as reports from health authorities in China3 are gathered and near real-time updates of the Johns Hopkins virus dashboard are made 4 The outbreak has caused governments in various countries to take swift and protective measures.In China,these included putting cities on lockdown,5 implementing travel wamings/bans and cancellations,6 extending national holidays,and closing schools and postponing classes7.  相似文献   
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75.
Although there have been a number of studies that compared the test results of the Wide Range Achievement Test (WRAT) and the Peabody Individual Achievement Test (PIAT), none had been accomplished with a group of college-aged learning disabled students. Indeed, few researchers had investigated populations over 16 years of age, and none had compared grade scores and standard scores with appropriate subtest scores as derived from these two instruments. With the recent emphasis on postsecondary education for the learning disabled, it is deemed critical that researchers should develop a data base for study of this population. The current research demonstrated that although both tests purport to measure academic achievement in reading, spelling, and arthmetic, in reality, significantly different scores are derived when WRAT (1965, 1978) norms are compared to PIAT (1970) norms as stated in grade scores and standard scores. These significant differences in the grade and standard scores clearly indicate that the WRAT and the PIAT, particularly in regard to arthmetic and to a lesser degree to reading, are not interchangeable instruments of academic achievement.  相似文献   
76.
Nearly 1000 regular classroom teachers were administered a scale designed to assess attitude toward mainstreaming. To determine the underlying dimensions of teacher attitude, a factor analysis of the intercorrelations of the items was conducted. Five dimensions were isolated that accounted for 52.4% of the variance. They were defined as attitude toward: (a) general philosophy of mainstreaming, (b) classroom behavior of special needs children, (c) perceived ability to teach the special needs child, (d) classroom management with special needs children, and (e) academic and social growth of the special needs child.  相似文献   
77.
We have developed a wet lab DNA microarray simulation as part of a complete DNA microarray module for high school students. The wet lab simulation has been field tested with high school students in Illinois and Maryland as well as in workshops with high school teachers from across the nation. Instead of using DNA, our simulation is based on pH indicators, which offer many ideal teaching characteristics. The simulation requires no specialized equipment, is very inexpensive, is very reliable, and takes very little preparation time. Student and teacher assessment data indicate the simulation is popular with both groups, and students show significant learning gains. We include many resources with this publication, including all prelab introductory materials (e.g., a paper microarray activity), the student handouts, teachers notes, and pre- and postassessment tools. We did not test the simulation on other student populations, but based on teacher feedback, the simulation also may fit well in community college and in introductory and nonmajors' college biology curricula.  相似文献   
78.
Energy balance of locomotion with pedal-driven watercraft   总被引:1,自引:0,他引:1  
In this study, we examined the mechanics and energetics of locomotion with a paddle-wheel boat and a water bike. Power output (Wtot) was measured directly on the water bike by means of an instrumented chain-ring. The simultaneous assessment of oxygen uptake (VO2) allowed the computation of the "overall" efficiency of locomotion (etao = Wtot/VO2). Mean etao was 0.27 (s = 0.02), which was unaffected by the speed, and was assumed to be the same for the two boats as both are semi-recumbent bicycles. For the paddle-wheel boat, Wtot was then obtained from etao and measures of VO2. The power to overcome (passive) drag was calculated as Wd = D x v (where D is the force measured by means of a load cell when towing the boats at given speeds). Propelling efficiency was calculated as etap = Wd/Wtot, which was lower with the paddle-wheel boat (mean 0.35, s = 0.01) than with the water bike (mean 0.57, s = 0.01). The observed differences in etap and Wd explain why at the highest speed tested (approximately 3 m s(-1), the energy required to cover a unit distance with the water bike is similar to that required to move the paddle-wheel boat at 1.3 m s-1).  相似文献   
79.
With organizations becoming leaner during times of cost consciousness, it is becoming critical that training departments demonstrate their contributions to their bottom lines by becoming more productivity based than they have been historically. For training professionals to obtain the needed financial and organizational support of their training efforts, top management should corroborate the training function. To gain this support, training professionals have evaluation procedures available to them. My purpose for conducting this study was to determine which type of training evaluation method (reaction, learning, behavior, or results) elicited the most management support of the training function among corporate managers. I designed and distributed a case study survey instrument (TEMS) to assess the extent of this support. MBA students with management experience and non-training managers participated in the study. For both samples, the data indicated that the results evaluation format received the most support, with progressively less support for behavior, learning, and reaction evaluations, respectively. I believe that this study provides training practitioners with a mandate for demonstrating training results to top management. It further gives an accountability system for gaining management support of the training function.  相似文献   
80.
There have been many conflicting observations between the linear or curvilinear decline in maximal heart rate (HRmax) with age. The aim of this study was to determine if linear or curvilinear equations would better describe the decline in HRmax with age in individuals of differing cardiorespiratory fitness (CRF) levels. Treadmill cardiopulmonary exercise test (CPX) results from participants (1510 men and 1134 women; 18–76 years) free of overt cardiovascular disease were retrospectively examined using cross-sectional and longitudinal study designs. Participants completing ≥2 CPX with ≥1 year between test dates were included in the longitudinal analysis (325 men and 150 women). Linear and quadratic regressions were applied to age and HRmax for the whole cohort and respective CRF groups (high, moderate, and low, relative to age and gender normative values). To test for differences among linear, quadratic, and polynomial equations, the change in R2 (cross-sectional analysis) and Bayesian information criterion (BIC) (longitudinal analysis) from the linear to the more complex models were calculated. The quadratic or polynomial regression in the cross-sectional analysis, marginally improved the variance in HRmax explained by age compared to the linear regression for the whole cohort (0.2%), moderate fit group (0.3%), and low fit group (0.8%). With no improvements in the high fit group. BIC did not improve for any CRF category in the longitudinal analysis. In conclusion, the minimal differences among linear, quadratic, and polynomial equations in the respective CRF groups, emphasizes the use of linear prediction equations to estimate HRmax.  相似文献   
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