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911.
912.
This chapter traces the way in which Nellie Kleinsmidt, known as the grandmother of karate in Africa, has negotiated discriminatory practices and overcome race and gender-related struggles, including the struggle to free the female body, in pursuit of empowerment. It explores her expectations and the constraints and frustrations she experienced, as well as the many contributions she has made to women's karate in South Africa. Nellie Kleinsmidt's karate career, which began in 1965, coincided with the early developments of South African karate. As a woman of colour her life and karate career were significantly shaped by apartheid legislation. It divided the country into areas of occupancy and residency according to race and was designed to prevent contact between the people of the government defined race groups. Black karate-kas were prohibited by law from practising karate in white designated areas. Lack of facilities and qualified instructors in areas allocated to Kleinsmidt's race group meant that she received very little formal karate instruction between 1966 and 1973. Soon after, she met Johan Roux, a white male. He was to become her chief karate instructor and life-long companion. They defied the apartheid legislation and in 1978 set up home together. They organized defiance campaigns, resisting the pressures from government to close their dojo because of its non-racial policies. Freeing her body at the broader political level involved the abolition of the race categories and all other apartheid legislation which impacted on her life choices and experiences. Initially this struggle and that of freeing her body occurred simultaneously. In her ongoing struggle against gender discrimination in the sport, it was in karate that Nellie Kleinsmidt could strive for the personal empowerment she sought. She could however not translate this into freedom in South African society itself. The impact of apartheid legislation together with the imposition of a sports moratorium by the South African Council on Sports (SACOS), hindered the growth of Nellie Kleinsmidt's karate career, yet she managed to obtain her sixth Dan Black Belt in 1998. This was a remarkable achievement given the constraints she had to overcome. In karate, Kleinsmidt was often viewed as a female first. The problem of female access is exacerbated by the overwhelming number of male instructors perpetuating the notion that the martial arts are inherently male sports. Accessing the various levels of karate has involved claiming physical and symbolic space on the dojo floor as well as involvement in the decision-making arenas of karate. In 1992 with the unification of karate in South Africa, Sensei Nellie began to extend her involvement with the refereeing arena and jointly established a Women's Karate Forum in her province. She has subsequently become a South African national referee and has earned the status of continental judge with the Union of African Karate Federation (UFAK). Nellie Kleinsmidt is the first and only woman of colour to have been appointed to the Referee's Board of South Africa and the only woman of colour in Africa to have obtained a sixth Dan Black belt. 相似文献
913.
Jones DS 《Isis; an international review devoted to the history of science and its cultural influences》2000,91(3):504-541
In the early 1970s physicians engaged in fierce debates over the most appropriate method of evaluating the efficacy of coronary artery bypass grafting (CABG). With millions of patients and billions of dollars at stake, CABG sparked fierce controversy. Skeptics demanded that randomized controlled trials (RCTs) be performed, while enthusiasts argued that they already had visual proof of CABG's efficacy. When RCTs appeared, they did not settle the controversy. Participants simply reasserted their preconceptions, defending a trial's strengths or exploiting its flaws. The debate centered on standards of knowledge for the evaluation of therapeutic efficacy. Specifically, cardiologists and cardiac surgeons struggled to assess the relevance of different measures of therapeutic success: physiological or clinical, visual or statistical. Many factors contributed to participants' decisions, including disciplinary affiliation, traditions of research, personal experience with angiography, and assessments of the history of cardiac therapeutics. Physicians had to decide whether angiography provided a meaningful representation of the disease and its treatment or whether demonstrations of therapeutic success could come only from long-term statistical evaluation of mortality data. 相似文献
914.
Blecic DD 《Bulletin of the Medical Library Association》2000,88(2):145-151
OBJECTIVE: To study the circulation of monographs during the first three years of shelf life at an academic health sciences library. METHOD: A record was kept of monographs added to the circulating collection from mid-1994 to mid-1995. After three years, each monograph was located and the number of times it circulated during the first, second, and third year of shelf life determined by counting checkout stamps on the circulation slip. RESULTS: Of the 1,958 monographs studied, 1,674 had complete data for the first three years of shelf life. Of those 1,674 titles, 81.48% circulated at least once. A total of 7,659 circulations were recorded; 38.69% occurred in the first year of shelf life, 32.37% in the second year, and 28.95% in the third year. The data did not fit the well-known 80/20 rule. Instead, approximately 38% of monographs accounted for 80% of circulation. A small percentage, 2.21%, of monographs accounted for a substantial percentage of circulation, 21.84%. CONCLUSIONS: A large percentage of the monographs circulated and use did not decline sharply with age within the first three years of shelf life, indicating a high demand for monographs at this academic health sciences library. These results, combined with the findings of earlier studies, suggested two possibilities. First, academic health sciences libraries might exhibit use of a higher percentage of monograph acquisitions than other types of libraries; or, second, a low monograph-to-user ratio might result in a higher percentage of monographs being used. Perhaps both factors contributed to the results found in this study. Further investigation would be needed to determine the extent to which library type and monograph-to-user ratio influenced monograph use. 相似文献
915.
916.
Six male cricket bowlers (mean +/- s(mean): age 23.5 +/- 1.3 years; height 1.83 +/- 0.04 m; body weight 826 +/- 20 N) performed their typical bowling action at a set of stumps positioned at standard pitch length (20.1 m). A specially designed force platform rig allowed the correct positioning of two force platforms to be achieved beneath an outdoor polyflex runway (0.017 m depth) for each player's delivery stride pattern. For the back foot, the peak vertical ground reaction force was 1.95 +/- 0.08 kN (2.37 +/- 0.14 BW) and the braking force was 0.77 +/- 0.12 kN (0.94 +/- 0.16 BW). For the front foot, the peak vertical force was 4.80 +/- 0.92 kN (5.75 +/- 0.98 BW) and the braking force was 2.93 +/- 0.56 kN (3.54 +/- 0.67 BW). The mean peak vertical loading rate for front foot contact was 205 +/- 52.8 kN x s(-1) (249 +/- 64 BW x s(-1)) with mean values ranging from 81 to 446 kN x s(-1) (98 to 540 BW x s(-1)). The range for back foot contact was much smaller, 25-70 kN x s(-1) (30-85 BW x s(-1)), with a mean of 41.7 +/- 7.10 kN x s(-1) (50.6 +/- 8.6 BW x s(-1)). Mean peak impact occurred 24 ms after touchdown for the back foot and 16 ms after touchdown for the front foot. At impact, mean peak loading rates were greater for the front foot at 246 kN x s(-1) (298 BW x s(-1)), with a range of 80-483 kN x s(-1) (98-534 BW x s(-1)), than for the back foot at 65 kN x s(-1) (79 BW x s(-1)), with a range of 40-84 kN x s(-1) (49-110 BW x s(-1)). 相似文献
917.
918.
A high ambient temperature reduces the capacity to perform prolonged exercise. Total carbohydrate oxidation is less, and thus glycogen depletion is not limiting. Fluid ingestion in the heat should, therefore, focus on maintenance of hydration status rather than on substrate provision. Six healthy males cycled to exhaustion at 60% of maximum oxygen consumption (VO2max) with no drink, ingestion of a 15% carbohydrate-electrolyte drink (1.45+/-0.29 litres) or ingestion of a 2% carbohydrate-electrolyte drink (3.12+/-0.47 litres). The ambient temperature was 30.2+/-0.6 degrees C (mean +/- s), with a relative humidity of 71+/-1% and an air speed of approximately 0.7 m x s(-1) on all trials. Weighted mean skin temperature, rectal temperature and heart rate were recorded and venous samples drawn for determination of plasma volume changes, blood metabolites, serum electrolytes and osmolality. Expired gas was collected to estimate rates of fuel oxidation. Exercise capacity was significantly (P < 0.05) different in all trials. The median (range) time to exhaustion was 70.9 min (39.4-97.4 min) in the no-drink trial, 84.0 min (62.7-145 min) in the 15% carbohydrate trial and 118 min (82.6-168 min) in the 2% carbohydrate trial. The 15% carbohydrate drink resulted in significantly (P < 0.05) elevated blood glucose and total carbohydrate oxidation compared with the no-drink trial. The 2% carbohydrate drink restored plasma volume to pre-exercise values by the end of exercise. No differences were observed in other thermoregulatory or cardiorespiratory responses between trials. These results suggest that fluid replacement with a large volume of a dilute carbohydrate drink is beneficial during exercise in the heat, but the precise mechanisms for the improved exercise capacity are unclear. 相似文献
919.
Woolf-May K Kearney EM Jones DW Davison RC Coleman D Bird SR 《Journal of sports sciences》1998,16(8):701-710
Forty-nine previously sedentary or low active individuals aged 40-71 years were allocated to three groups. The long walking group participated in an 18-week walking programme which consisted of walks lasting 20-40 min; the repetitive short walking group completed walks of between 10 and 15 min, up to three times a day, with no less than 120 min between each walk; and the control group maintained their low level of activity. Both walking programmes began at a prescribed 60 min x week(-1), which increased steadily up to 200 min x week(-1) by week 12. During the study, the long walking group walked for an estimated 2514 min (139 min x week(-1)), expending an estimated 67.5 MJ (3.72 MJ x week(-1)) at an estimated 73% of their age-predicted maximum heart rate and 68% of their estimated VO2max. The repetitive short walking group walked for an estimated 2476 min (135 min x week(-1)), expending an estimated 58.5 MJ (3.17 MJ x week(-1)) at an estimated 71% of their age-predicted maximum heart rate and 65% of their estimated VO2max. The results showed a statistically significant reduction in heart rate during a standardized step test (pre- vs post-intervention) in both walking groups, indicating an improvement in aerobic fitness, although the control group showed a higher average heart rate during the post-intervention test, indicating reduced fitness. When compared with the male subjects pre-intervention, the females possessed more favourable levels of high-density lipoprotein (HDL) cholesterol (P< 0.001), apolipoprotein (apo) AI (P < 0.001) and ratios of total cholesterol:HDL cholesterol (P< 0.02) and low-density lipoprotein (LDL) cholesterol: HDL cholesterol (P< 0.02). Compared with the controls post-intervention, the walking groups showed no statistically significant changes in total cholesterol, LDL cholesterol, HDL cholesterol, apo AI, apo AII, apo B, or the ratios of total cholesterol: HDL cholesterol, LDL cholesterol: HDL cholesterol, apo AI: apo B or apo AI: apo AII (P > 0.05). Relative to the walking groups, factor XIIa increased in the control group (P < 0.05). We conclude that, although both walking programmes appeared to improve aerobic fitness, there was no evidence of improvements in the blood lipids or associated apolipoproteins of the walking groups. Further analysis indicated that this apparent lack of change may have been related to the subjects' relatively good pre-intervention blood lipid profiles, which restricted the potential for change. The implications of the observed changes in the coagulation/fibrinolytic factors remain unclear. 相似文献
920.