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61.
Based on their performance on a standardized achievement test, second-grade children (N = 49) were classified as having mathematics difficulties with normal reading achievement (MD only), both mathematics and reading difficulties (MD/RD), reading difficulties with normal mathematics achievement (RD only) and normal mathematics and reading achievement (NA). Each child was given a series of tasks so that we might assess their thinking across four areas of mathematics: number facts, story problems, place value, and written calculation. Children with MD/RD performed significantly worse than NA children in most areas of mathematical thinking, whereas children with MD only performed worse than NA children only on complex story problems. The MD-only group outperformed the MD/RD group on story problems and written calculation. No significant differences were found between the RD-only and NA groups on any of the tasks. The results suggested that among children with mathematics difficulties, the MD/RD subgroup is distinct from the MD-only subgroup, with the former being characterized by pervasive deficiencies in mathematical thinking and the latter by more specific deficits in problem solving. 相似文献
62.
Children's number sense in kindergarten was used to predict their calculation fluency in second grade (N = 198). Using block entry regression, usual predictors of age, reading, memory, and verbal and spatial cognition were entered in the first block and number sense measures were added in the second block. Number sense measures contributed a significant amount of variance over and above the more general predictors (26%-42%). Uniquely predictive subareas were active memory for numbers, number knowledge, and number combinations, with number combinations standing out as the strongest single predictor. Number sense screening in kindergarten, using "at-risk" versus "not-at-risk" criteria, successfully ruled out 84% of the children who did not go on to have calculation fluency difficulties and positively identified 52% of the children who later showed fluency difficulties. The relation of early number skills to later calculation fluency has important implications for math screening and intervention. 相似文献
63.
Benedicta D’Souza Vivian D’Souza S. Sowmya G. Seema C. N. Hemalatha M. Anu G. Sajana 《Indian journal of clinical biochemistry : IJCB》2008,23(3):218-222
The study was conducted to find out the extent of lipid peroxidation and antioxidant status in ischemic stroke patients (ISPs)
with and without diabetes. Malondialdehyde (MDA) was studied as a marker of lipid peroxidation. Glutathione (GSH), uric acid
and ceruloplasmin were estimated to study the antioxidant potential of ISPs. Significantly higher levels of MDA were found
in both the groups of ISPs and the increase in MDA was more in ISPs without diabetes. GSH levels were decreased significantly
in both the groups of ISPs and maximum decline was found in ISPs with diabetes. Uric acid levels were significantly increased
in both the groups of ISPs. Ceruloplasmin levels were increased significantly in ISPs without diabetes, whereas its levels
were slightly decreased in ISPs with diabetes. A negative correlation was found between MDA and the antioxidants GSH, uric
acid and ceruloplasmin in ISPs with diabetes. This study suggests that there is an association between ischemic stroke and
increased oxidative stress and the antioxidant potential is impaired in both the groups of ISPs with and without diabetes. 相似文献
64.
Poonam Gautam Taruna Madan W. N. Gade P. Usha Sarma 《Indian journal of clinical biochemistry : IJCB》2006,21(2):12-19
Allergenic/antigenic proteins are known to induce Type I and Type III hypersensitivity reactions leading to allergic bronchopulmonary
aspergillosis (ABPA) in immunocompetent host. The common structural features or intrinsic properties of the allergens/antigens
leading to allergenicity in a host are not well understood. In the current report, comparative analysis of proteins on two
dimensional gel electrophoresis (2D-3) and specific IgE immunoblots ofA. fumigatus secretory proteins (1st, 2nd and 3rd week culture filtrate proteins) was carried out. We observed a total of 159 proteins in 1st, 2nd and 3rd week culture filtrates ofA. fumigatus. Specific IgE immunoreactivity was observed in 75 proteins with different intensity. Third week culture filtrate showed maximum
number of proteins, 142, and specific IgE immunoreactive proteins, 65. MALDI-TOF analysis resulted in putative identification
of two allergens as hypothetical protein YBL057c fromSaccharomyces cereviseae and unnamed protein product fromDebaryomyces hansenii (similar to IPF14568 ofCandida albicans). Identification of a repertoire of specific IgE immunoreactive proteins will facilitate the studies on structure-function
relationship of these proteins relevant for diagnosis and pathogenesis. 相似文献
65.
Patenting and US academic research in the 20th century: The world before and after Bayh-Dole 总被引:2,自引:0,他引:2
Bhaven N. Sampat 《Research Policy》2006,35(6):772-789
The dramatic growth of patenting and licensing of publicly funded research by American research universities in the closing quarter of the 20th century has stimulated some of the highest-profile debates in science and technology policy today. The issue of what aspects of academic research should be public - and what private - lies at the heart of each of these debates. The movement of academic scientists into commercialisation of discoveries and inventions has been extolled by some as a new model of academic research, one which facilitates economic and social returns from universities. At the same time, this trend has been criticised by others as representing a socially inefficient ‘privatisation’ of academic research and as a threat to the ethos of science itself. This paper places these debates in historical context, with a review of changes in American universities’ patenting policies, procedures and practices throughout the 20th century, an assessment of the logic underlying the passage of the Bayh-Dole Act of 1980, and an overview of its effects on economic returns from university research. 相似文献
66.
N. Unni C. Sumithra R. Lakshman Lakshmi N. Leela Menon K. N. Subhakumari V. S. Sheejamol 《Indian journal of clinical biochemistry : IJCB》2015,30(2):161-166
PCOS is a heterogeneous endocrine disorder with diverse clinical presentation. Oxidative stress plays a key role in the pathophysiology of this disease. Serumhigh sensitive C-reactive protein (hsCRP), a marker of chronic low grade inflammation, is indicative of future development of cardiovascular disease. Our aim is to evaluate the oxidant status and hsCRP levels in PCOS. The study involved 61 cases and 61 controls in the age group of 18–40 years diagnosed with PCOS. Erythrocyte malondialdehyde (MDA), superoxide dismutase (SOD), serum hsCRP, gonadotrophins, thyroid stimulating hormone, prolactin, glycemic status and lipid profile were estimated. Erythrocyte MDA (p < 0.001), SOD (p = 0.007) and serum hsCRP (p < 0.001) were significantly elevated in PCOS patients than controls. Oxidative stress is present in women with PCOS along with elevated hsCRP. 相似文献
67.
Intersample optimization in a sampled-data control system using the redundancy of a dual-rate system
The present study discusses the design method for controlling a single-input/single-output linear time-invariant dual-rate system, where the sampling interval of the plant output is longer than the holding interval of the control input. In such a dual-rate system, the intersample output might oscillate even when the sampled output converges to the reference input in the steady state. In a conventional ripple-free method, an existing control law is extended by introducing an exogenous variable, which is independent of the discrete-time sampled response, and the exogenous variable is designed for eliminating the steady-state intersample ripples without changing the existing sampled response. In another method, since a control law is designed such that the intersample performance is optimized, the intersample ripples are eliminated in the transient as well as steady states. However, the preservation of an existing sampled response is not taken into account. The present study proposes a new design method for eliminating the intersample ripples subject to the existing sampled response. In the proposed method, the continuous-time index is optimized subject to the existing discrete-time response. As a result, the intersample ripples are eliminated in the transient as well as steady states, and the existing discrete-time sampled response is maintained. The proposed method is compared to the conventional dual-rate design methods in numerical examples, and the effectiveness of the method is demonstrated. 相似文献
68.
J. B. Varuna Kumara N. R. Ravikumara Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2016,31(4):390-401
Folic acid is used for preventing and treating multiple diseases and disorders, administered in the form of oral supplements. The present research work was aimed to study the influence of two non-ionic surfactants Poloxamer and Tween 80 (Polysorbate 80) on pectin submicrospheres formulations. Typical natural polymer pectin was used to encapsulate folic acid by cross linking method. The resultant submicrospheres contributed to improve the aqueous solubility to enhance the bioavailability of folic acid. During investigation, it was observed that pectin polymers influenced kinetics of the rate of reaction more intensively than the surfactants. The physical phenomenon caused the change in their size, shape and chemistry of pectin polymers transforming into submicrospheres in aqueous condition. The characteristic differences of submicrospheres were assessed by scanning electron microscopy, differential scanning calorimetry and Fourier-transform infrared spectroscopy. The average diameters of the submicrospheres ranged between 250 and 500 nm. The encapsulation efficiency of submicrospheres ranged between 80 and 96 %. The characteristic swelling behavior of lyophilized submicrospheres was influenced by the ratio of pectin polymers and folic acid used in the formulations. The submicrospheres systems exhibited controlled release of folic acid due to the pH-dependent solubility of pectin polymers in aqueous medium. The submicrospheres showed good haemocompatibility suggesting them to be promising candidates for oral delivery. 相似文献
69.
几种蒸散模型在玉米农田蒸散量计算中的应用比较 总被引:2,自引:1,他引:2
模拟蒸散的物理过程,计算农田蒸散量是进行生态系统水资源评价和管理的重要手段,同时也是气象部门进行土壤湿度预报的首要条件.本研究以玉米农田为研究对象,基于涡度相关法观测的蒸散实测资料,比较分析了基于常规气象数据的蒸散模型(Hargreaves法、Priestlev-Taylor法、FAO-Penman-Monteith法)和基于气象梯度数据的蒸散模型(波文比法、梯度法、生态系统过程模型模拟)的模拟精度.结果表明:①Hargreaves法、Priestley-Taylor法和FAO-Penman-Monteith法日蒸散的模拟结果较为一致,总体上高估20%~26%,其中Priestley-Taylor法模拟结果最优;②生态系统过程模型模拟的农田日蒸散精度较高,但模型中涉及的物理过程和参数较多,在实际应用中难于获取;③波文比法在波文比小于0.4且仪器精度较高时可以得到较准确的估算值.研究同时还指出,仪器的安装高度及高差设计对梯度法估算蒸散十分重要. 相似文献
70.
Electrospinning, a flexible jet-based fiber, scaffold, and membrane fabrication approach, has been elucidated as having significance to the heath sciences. Its capabilities have been most impressive as it possesses the ability to spin composite fibers ranging from the nanometer to the micrometer scale. Nonetheless, electrospinning has limitations and hazards, negating its wider exploration, for example, the inability to handle highly conducting suspensions, to its hazardous high voltage. Hence, to date electrospinning has undergone an exhaustive research regime to a point of cliché. Thus, in the work reported herein we unveil a competing technique to electrospinning, which has overcome the above limitations and hazards yet comparable in capabilities. The fiber preparation approach unearthed herein is referred to as “pressure driven spinning (PDS).” The driving mechanism exploited in this fiber spinning process is the pressurized by-pass flow. This mechanism allows the drawing of either micro- or nanosized fibers while processing polymeric suspensions containing a wide range of advanced materials spanning structural, functional, and biological entities. Similar to electrospinning if the collection time of these continuous formed fibers is varied, composite scaffolds and membranes are generated. In keeping with our interests, multicompositional structural entities such as these could have several applications in biology and medicine, for example, ranging from the development of three-dimensional cultures (including disease models) to the development of synthetic tissues and organ structures to advanced approaches for controlled and targeted therapeutics. 相似文献