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931.
We identified the perceptual–cognitive skills and player history variables that differentiate players selected or not selected into an elite youth football (i.e. soccer) programme in Australia. A sample of elite youth male football players (n?=?127) completed an adapted participation history questionnaire and video-based assessments of perceptual–cognitive skills. Following data collection, 22 of these players were offered a full-time scholarship for enrolment at an elite player residential programme. Participants selected for the scholarship programme recorded superior performance on the combined perceptual–cognitive skills tests compared to the non-selected group. There were no significant between group differences on the player history variables. Stepwise discriminant function analysis identified four predictor variables that resulted in the best categorization of selected and non-selected players (i.e. recent match-play performance, region, number of other sports participated, combined perceptual–cognitive performance). The effectiveness of the discriminant function is reflected by 93.7% of players being correctly classified, with the four variables accounting for 57.6% of the variance. Our discriminating model for selection may provide a greater understanding of the factors that influence elite youth talent selection and identification. 相似文献
932.
Guy A. Marco 《International Information and Library Review》2013,45(4):357-363
The training of information personnel at the middle level in Africa is discussed. The data were derived from the latest issues of the prospectuses of the library schools at the University of Ibadan and Botswana as well as a questionnaire designed to ascertain the characteristics of the trainees in both institutions. The study reveals that the curricula of both schools extend beyond preparing trainees for the techniques and processes of a library. The trainees in both schools have sufficient educational background and library/information work experience to enable them to manage the many one-man libraries scattered all over Africa effectively, after undergoing the diploma training. It is recommended that an amalgam of the curricula of both schools can be made the standard curriculum for any institution involved in a training programme for information personnel at this level. 相似文献
933.
Recently direct optimization of information retrieval (IR) measures has become a new trend in learning to rank. In this paper,
we propose a general framework for direct optimization of IR measures, which enjoys several theoretical advantages. The general
framework, which can be used to optimize most IR measures, addresses the task by approximating the IR measures and optimizing
the approximated surrogate functions. Theoretical analysis shows that a high approximation accuracy can be achieved by the
framework. We take average precision (AP) and normalized discounted cumulated gains (NDCG) as examples to demonstrate how
to realize the proposed framework. Experiments on benchmark datasets show that the algorithms deduced from our framework are
very effective when compared to existing methods. The empirical results also agree well with the theoretical results obtained
in the paper. 相似文献
934.
935.
936.
India seems to have the highest prevalence of osteoporosis. With growing awareness of osteoporosis and its impact on life
span especially in India, special attention is being paid to early detection, management and treatment of postmenopausal osteoporosis
in women. Measurement of BMD and osteocalcin are of value in estimating bone turnover rates. The aim of this study is (1)
to measure the specific, sensitive bone formation marker such as osteocalcin and BMD in postmenopausal osteoporosis women
and postmenopausal non-osteoporosis women; (2) the follow up study to evaluate the impact of specific antiresorptive therapy
(alendronate + calcium + vitamin D) regimen in postmenopausal osteoporosis by assaying osteocalcin and BMD. Sixty clinically
diagnosed postmenopausal osteoporosis patients and 60 normal subjects (postmenopausal non-osteoporosis women) were recruited
as control. Mean bone mineral density T score and Z score was significantly decreased (P < 0.001) in postmenopausal osteoporosis patients as compared to controls. Highly significant increase in the mean score of
BMD—T score and Z score from baseline to post therapy of 3 months was observed in postmenopausal osteoporosis women. Serum osteocalcin levels
were significantly increased (P < 0.001) as compared to control group. Serum osteocalcin levels were decreased significantly (P < 0.001) from baseline to post therapy of 3 months in postmenopausal osteoporosis women. BMD is the best quantifiable predictor
of osteoporotic fracture and osteocalcin is specific, sensitive, promising, currently used marker for better prognosis of
osteoporosis and for monitoring responses to antiresorptive therapy. 相似文献
937.
Induction of diabetes by Streptozotocin in rats 总被引:1,自引:0,他引:1
A. Akbarzadeh D. Norouzian M. R. Mehrabi Sh. Jamshidi A. Farhangi A. Allah Verdi S. M. A. Mofidian B. Lame Rad 《Indian journal of clinical biochemistry : IJCB》2007,22(2):60-64
The objective of this study is to induce experimental diabetes mellitus by Streptozotocin in normal adult Wistar rats via
comparison of changes in body weight, consumption of food and water, volume of urine and levels of glucose, insulin and C-peptide
in serum, between normal and diabetic rats. Intra-venous injection of 60mg/kg dose of Streptozotocin in adult wistar rats,
makes pancreas swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes mellitus
in the 2–4 days. Induction of experimental diabetes mellitus is indeed the first step in the plan of purification of pancreatic
Langerhans islet cells of normal rats for transplanting under the testis subcutaneous of experimentally induced diabetic rats.
Streptozotocin induces one type of diabetes which is similar to diabetes mellitus with non-ketosis hyperglycemia in some animal
species. For induction of experimental diabetes in male adult rats weighted 250–300 grams (75–90 days), 60mg/kg of Streptozotocin
was injected intravenously. Three days after degeneration of beta cells, diabetes was induced in all animals. The diabetic
and normal animals were kept in the metabolic cages separately and their body weight, consumption of food and water, urine
volume, the levels of serum glucose, insulin and C-peptide quantities in all animals were measured and then these quantities
were compared. For a microscopic study of degeneration of Langerhans islet beta cells of diabetic rats, sampling from pancreas
tissue of diabetic and normal rats, staining and comparison between them, were done. Induction of diabetes with Streptozotocin
decreases Nicotinamide-adenine dinucleotide (NAD) in pancreas islet beta cells and causes histopathological effects in beta
cells which probably intermediates induction of diabetes. In this study, we used Streptozotocin for our experiments in induction
of experimental diabetes mellitus. After Induction of diabetes, consumption of food and water, volume of urine and glucose
increased in the diabetic animals in comparison with normal animals, but the weight of body and the volume of insulin and
C-peptide decreased in the diabetic animals. Sampling and staining of pancreas tissue of diabetic and normal rats showed that
the Langerhans islet beta cells of diabetic rats have been clearly degenerated. In three days, Streptozotocin makes pancreas
swell and at last causes degeneration in Langerhans islet beta cells and induces experimental diabetes. It also changes normal
metabolism in diabetic rats in comparison with normal rats. Consumption of water and food, volume of urine, serum glucose
increases in diabetic animals in comparison with normal rats but the levels of serum insulin, C-peptide and body weight decreases. 相似文献
938.
Ethics and Information Technology - Should we welcome social robots into interpersonal relationships? In this paper I show that an adequate answer to this question must take three factors into... 相似文献
939.
Two rhesus monkeys were tested in 6- and 10-item list memory tasks for performance changes as a function of the exposure duration of the list stimuli and the interstimulus interval (ISI) between successive list stimuli. Accuracy increased with longer item exposure duration and tended to decrease with longer ISI duration. Humans, by contrast, typically show increases in accuracy with ISI, a result taken as evidence of rehearsal. The decrease in accuracy for monkeys suggests that they were not using rehearsal processes in these list memory experiments. Further tests in which choice accuracy with predictable ISIs was compared with choice accuracy with unpredictable ISIs also yielded no evidence of rehearsal by the monkeys. This apparent absence of rehearsal mechanisms in monkeys, in situations also shown to support human rehearsal, is discussed as a potential difference in the visual working memory processes of the two species. 相似文献
940.
Soumela Atmatzidou Stavros Demetriadis Panagiota Nika 《Journal of Science Education and Technology》2018,27(1):70-85
Educational robotics (ER) is an innovative learning tool that offers students opportunities to develop higher-order thinking skills. This study investigates the development of students’ metacognitive (MC) and problem-solving (PS) skills in the context of ER activities, implementing different modes of guidance in two student groups (11–12 years old, N1 = 30, and 15-16 years old, N2 = 22). The students of each age group were involved in an 18-h group-based activity after being randomly distributed in two conditions: “minimal” (with minimal MC and PS guidance) and “strong” (with strong MC and PS guidance). Evaluations were based on the Metacognitive Awareness Inventory measuring students’ metacognitive awareness and on a think-aloud protocol asking students to describe the process they would follow to solve a certain robot-programming task. The results suggest that (a) strong guidance in solving problems can have a positive impact on students’ MC and PS skills and (b) students reach eventually the same level of MC and PS skills development independently of their age and gender. 相似文献