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501.
In social networks, the structural balance is a state of a group of individuals(nodes) with established mutual relationships(connection relationships) between them. It is easy to see that a social network can be described by a complex dynamical network model composed of the nodes subsystem(NS) and the connection relationships subsystem(CS), where the two subsystems are usually coupled with each other. It implies that the dynamic changes of nodes' states may cause the structural balance in CS. However, few papers have discussed the relationship between the structural balance and the specific dynamic changes of the nodes' states. This paper proposes a model of complex dynamical networks, and mainly focuses on the dynamic changes of states in NS which can lead to the structural balance in CS. It is proved that if each state in NS is doing a specific dynamic motion via the controller with the parameter adaptive law, then the CS can track a given structural balance matrix via the effective coupling and the structural balance can be achieved. Such a result can be regarded as an explanation of the relationship between the structural balance and the specific dynamic changes of the nodes' states. Finally, the simulations verify the effectiveness of the proposed method. 相似文献
502.
将模糊自适应PID控制和最佳启停控制相结合应用于智能楼宇中的空调监控系统中,经研究发现运用此方法后,系统的超调小了,而且调节迅速、上升时间短,具有良好的鲁棒性和节能效果。 相似文献
503.
504.
纳米二氧化钛是一种重要的无机功能材料。本文采用溶胶-凝胶法制备了TiO_2薄膜,利用"场助"影响其光催化特性。光催化实验以可能具有致癌性并且难以生化降解的三苯甲烷类染料——甲紫作为降解物质,用2100型分光光度计来测量降解率,以确定电场、磁场强度对光催化特性的影响。光催化实验结果表明,外加电场(未参与水的电解)、磁场对于协助光催化降解甲紫有着明显的效果。随着外加电场、磁场强度的增加,甲紫溶液的降解率有大幅提高。反应符合一级动力学方程。 相似文献
505.
在多尺度框架下,提出基于非线性复扩散模型憎水性图像水珠亮点检测算法,最后采用模糊均类算法对多尺度虚部图像水珠亮点进行提取。实验结果表明:对于不同憎水性等级憎水性图像,水珠亮点检测都达到95%以上,这为对绝缘子憎水性等级估判及水珠(水迹)的进一步分割提供了重要的信息。 相似文献
506.
KI Cho K Searle M Webb H Yi PA Ferreira 《Cellular and molecular life sciences : CMLS》2012,69(20):3511-3527
Many components and pathways transducing multifaceted and deleterious effects of stress stimuli remain ill-defined. The Ran-binding protein 2 (RanBP2) interactome modulates the expression of a range of clinical and cell-context-dependent manifestations upon a variety of stressors. We examined the role of Ranbp2 haploinsufficiency on cellular and metabolic manifestations linked to tyrosine-hydroxylase (TH(+)) dopaminergic neurons and glial cells of the brain and retina upon acute challenge to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), a parkinsonian neurotoxin, which models facets of Parkinson disease. MPTP led to stronger akinetic parkinsonism and slower recovery in Ranbp2 (+/-) than wild-type mice without viability changes of brain TH(+)-neurons of either genotype, with the exception of transient nuclear atypia via changes in chromatin condensation of Ranbp2 (+/-) TH(+)-neurons. Conversely, the number of wild-type retinal TH(+)-amacrine neurons compared to Ranbp2 (+/-) underwent milder declines without apoptosis followed by stronger recoveries without neurogenesis. These phenotypes were accompanied by a stronger rise of EdU(+)-proliferative cells and non-proliferative gliosis of GFAP(+)-Müller cells in wild-type than Ranbp2 (+/-) that outlasted the MPTP-insult. Finally, MPTP-treated wild-type and Ranbp2 (+/-) mice present distinct metabolic footprints in the brain or selective regions thereof, such as striatum, that are supportive of RanBP2-mediated regulation of interdependent metabolic pathways of lysine, cholesterol, free-fatty acids, or their β-oxidation. These studies demonstrate contrasting gene-environment phenodeviances and roles of Ranbp2 between dopaminergic and glial cells of the brain and retina upon oxidative stress-elicited signaling and factors triggering a continuum of metabolic and cellular manifestations and proxies linked to oxidative stress, and chorioretinal and neurological disorders such as Parkinson. 相似文献
507.
Lin Z Bei JX Shen M Li Q Liao Z Zhang Y Lv Q Wei Q Low HQ Guo YM Cao S Yang M Hu Z Xu M Wang X Wei Y Li L Li C Li T Huang J Pan Y Jin O Wu Y Wu J Guo Z He P Hu S Wu H Song H Zhan F Liu S Gao G Liu Z Li Y Xiao C Li J Ye Z He W Liu D Shen L Huang A Wu H Tao Y Pan X Yu B Tai ES Zeng YX Ren EC Shen Y Liu J Gu J 《Nature genetics》2012,44(1):73-77
To identify susceptibility loci for ankylosing spondylitis, we performed a two-stage genome-wide association study in Han Chinese. In the discovery stage, we analyzed 1,356,350 autosomal SNPs in 1,837 individuals with ankylosing spondylitis and 4,231 controls; in the validation stage, we analyzed 30 suggestive SNPs in an additional 2,100 affected individuals and 3,496 controls. We identified two new susceptibility loci between EDIL3 and HAPLN1 at 5q14.3 (rs4552569; P = 8.77 × 10(-10)) and within ANO6 at 12q12 (rs17095830; P = 1.63 × 10(-8)). We also confirmed previously reported associations in Europeans within the major histocompatibility complex (MHC) region (top SNP, rs13202464; P < 5 × 10(-324)) and at 2p15 (rs10865331; P = 1.98 × 10(-8)). We show that rs13202464 within the MHC region mainly represents the risk effect of HLA-B*27 variants (including HLA-B*2704, HLA-B*2705 and HLA-B*2715) in Chinese. The two newly discovered loci implicate genes related to bone formation and cartilage development, suggesting their potential involvement in the etiology of ankylosing spondylitis. 相似文献
508.
Gui Y Guo G Huang Y Hu X Tang A Gao S Wu R Chen C Li X Zhou L He M Li Z Sun X Jia W Chen J Yang S Zhou F Zhao X Wan S Ye R Liang C Liu Z Huang P Liu C Jiang H Wang Y Zheng H Sun L Liu X Jiang Z Feng D Chen J Wu S Zou J Zhang Z Yang R Zhao J Xu C Yin W Guan Z Ye J Zhang H Li J Kristiansen K Nickerson ML Theodorescu D Li Y Zhang X Li S Wang J Yang H Wang J Cai Z 《Nature genetics》2011,43(9):875-878
Transitional cell carcinoma (TCC) is the most common type of bladder cancer. Here we sequenced the exomes of nine individuals with TCC and screened all the somatically mutated genes in a prevalence set of 88 additional individuals with TCC with different tumor stages and grades. In our study, we discovered a variety of genes previously unknown to be mutated in TCC. Notably, we identified genetic aberrations of the chromatin remodeling genes (UTX, MLL-MLL3, CREBBP-EP300, NCOR1, ARID1A and CHD6) in 59% of our 97 subjects with TCC. Of these genes, we showed UTX to be altered substantially more frequently in tumors of low stages and grades, highlighting its potential role in the classification and diagnosis of bladder cancer. Our results provide an overview of the genetic basis of TCC and suggest that aberration of chromatin regulation might be a hallmark of bladder cancer. 相似文献
509.
A rare penetrant mutation in CFH confers high risk of age-related macular degeneration 总被引:1,自引:0,他引:1
510.
在分析企业系统复杂性影响因素的基础上,指出企业可以通过合理配置复杂性、组织设计、文化建设等方面降低不合理的复杂性;提高个体认知和处理复杂性的能力;为增加有效复杂性提供空间;形成企业核心竞争力。 相似文献