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991.
Background
Epilepsy is a severe neurological disorder affecting a large number of individuals, yet the underlying genetic risk factors for epilepsy remain unclear. Recent studies have revealed several recurrent copy number variations (CNVs) that are more likely to be associated with epilepsy. The responsible gene(s) within these regions have yet to be definitively linked to the disorder, and the implications of their interactions are not fully understood. Identification of these genes may contribute to a better pathological understanding of epilepsy, and serve to implicate novel therapeutic targets for further research.Methodology/Principal Findings
In this study, we examined genes within heterozygous deletion regions identified in a recent large-scale study, encompassing a diverse spectrum of epileptic syndromes. By integrating additional protein-protein interaction data, we constructed subnetworks for these CNV-region genes and also those previously studied for epilepsy. We observed 20 genes common to both networks, primarily concentrated within a small molecular network populated by GABA receptor, BDNF/MAPK signaling, and estrogen receptor genes. From among the hundreds of genes in the initial networks, these were designated by convergent evidence for their likely association with epilepsy. Importantly, the identified molecular network was found to contain complex interrelationships, providing further insight into epilepsy''s underlying pathology. We further performed pathway enrichment and crosstalk analysis and revealed a functional map which indicates the significant enrichment of closely related neurological, immune, and kinase regulatory pathways.Conclusions/Significance
The convergent framework we proposed here provides a unique and powerful approach to screening and identifying promising disease genes out of typically hundreds to thousands of genes in disease-related CNV-regions. Our network and pathway analysis provides important implications for the underlying molecular mechanisms for epilepsy. The strategy can be applied for the study of other complex diseases. 相似文献992.
Zhou YH Tang LG Guo SL Jin ZC Wu MJ Zang JJ Xu JF Wu CF Qin YY Cai Q Gao QB Zhang SS Yu DH He J 《PloS one》2011,6(4):e18788
Background
Studies have shown that steroids can improve kidney survival and decrease the risk of proteinuria in patients with Immunoglobulin A nephropathy, but the overall benefit of steroids in the treatment of Immunoglobulin A nephropathy remains controversial. The aim of this study was to evaluate the benefits and risks of steroids for renal survival in adults with Immunoglobulin A nephropathy.Methodology and Principal Findings
We searched the Cochrane Renal Group Specialized Register, Cochrane Controlled Trial Registry, MEDLINE and EMBASE databases. All eligible studies were measuring at least one of the following outcomes: end-stage renal failure, doubling of serum creatinine and urinary protein excretion. Fifteen relevant trials (n = 1542) that met our inclusion criteria were identified. In a pooled analysis, steroid therapy was associated with statistically significant reduction of the risk in end-stage renal failure (RR: 0.46, 95% CI: 0.27 to 0.79), doubling of serum creatinine (RR = 0.34, 95%CI = 0.15 to 0.77) and reduced urinary protein excretion (MD = −0.47g/day, 95%CI = −0.64 to −0.31).Conclusions/Significance
We identified that steroid therapy was associated with a decrease of proteinuria and with a statistically significant reduction of the risk in end-stage renal failure. Moreover, subgroup analysis also suggested that long-term steroid therapy had a higher efficiency than standard and short term therapy. 相似文献993.
Wang Y Tong J Li S Zhang R Chen L Wang Y Zheng M Wang M Liu G Dai Y Zhao Y Li N 《PloS one》2011,6(6):e20895
Background
The mammary gland is a conserved site of lipoprotein lipase expression across species and lipoprotein lipase attachment to the luminal surface of mammary gland vascular endothelial cells has been implicated in the direction of circulating triglycerides into milk synthesis during lactation.Principal Findings
Here we report generation of transgenic mice harboring a human lipoprotein lipase gene driven by a mammary gland-specific promoter. Lipoprotein lipase levels in transgenic milk was raised to 0.16 mg/ml, corresponding to an activity of 8772.95 mU/ml. High lipoprotein lipase activity led to a significant reduction of triglyceride concentration in milk, but other components were largely unchanged. Normal pups fed with transgenic milk showed inferior growth performances compared to those fed with normal milk.Conclusion
Our study suggests a possibility to reduce the triglyceride content of cow milk using transgenic technology. 相似文献994.
995.
Cassava genetic transformation and its application in breeding 总被引:1,自引:0,他引:1
As a major source of food, cassava (Manihot esculenta Crantz) is an important root crop in the tropics and subtropics of Africa and Latin America, and serves as raw material for the production of starches and bioethanol in tropical Asia. Cassava improvement through genetic engineering not only overcomes the high heterozygosity and serious trait separation that occurs in its traditional breeding, but also quickly achieves improved target traits. Since the first report on genetic transformation in cassava in 1996, the technology has gradually matured over almost 15 years of development and has overcome cassava genotype constraints, changing from mode cultivars to farmer-preferred ones. Significant progress has been made in terms of an increased resistance to pests and diseases, biofortification, and improved starch quality, building on the fundamental knowledge and technologies related to planting, nutrition, and the processing of this important food crop that has often been neglected. Therefore, cassava has great potential in food security and bioenergy development worldwide. 相似文献
996.
目的:比较1,25(OH)2D3缺失对膜内成骨和软骨内成骨影响的不同。方法:用免疫组织化学染色、HE染色和Western-blot等方法检测6周龄的野生型(wild type,WT)和1琢(OH)ase-/-小鼠的颅骨和股骨干骺端骨组织中I型胶原和甲状旁腺素受体(parathyroid hormone receptor,PTHR)的表达水平。结果:和WT小鼠相比较,1 ase-/-小鼠颅骨的I型胶原阳性面积明显减少,但是干骺端I型胶原阳性面积明显增加,差异有显著性(P<0.01);1琢(OH)ase-/-小鼠颅骨成骨细胞计数明显减少,差异存在统计学意义(P<0.05);但是干骺端成骨细胞计数明显增加,差异有显著性(P<0.01);1琢(OH)ase-/-小鼠颅骨的PHTR表达水平明显减少,但是在干骺端PHTR表达水平明显增加,差异均有显著性(P<0.01)。结论:1,25(OH)2D3缺乏导致小鼠膜内成骨方式骨形成减少,而软骨内成骨骨形成增加。 相似文献
997.
利用黑曲霉β-葡萄糖苷酶催化香兰素葡萄糖苷水解 总被引:2,自引:0,他引:2
本文通过在香兰素葡萄糖苷溶液中加入黑曲霉菌种发酵制取的β-葡萄糖苷酶,进行酶促反应实验,定时取样进行高效液相分析检测,结果表明在反应过程中,溶液中香兰素葡萄糖苷的含量呈逐步下降趋势,香兰素的量呈逐步增加趋势;而在没有加β-葡萄糖苷酶的对照实验中,整个反应过程中香兰素葡萄糖苷的含量基本没有出现什么变化,在反应液中也没有检测到香兰素,这说明黑曲霉β-葡萄糖苷酶能够催化香兰素葡萄糖苷分解为香兰素的反应. 相似文献
998.
Wang XF Zheng HY Zheng WH Ao CQ Jin HY Zhao LH Li N Jia LR 《Genetics and molecular research : GMR》2011,10(2):849-859
Camellia is an economically important ornamental plant that has many uses, such as in beverages, foods and medicines. We examined 15 Camellia cultivars in Wenzhou, China, using RAPD markers and measurements of three traits (petal color, flower diameter, blooming period). PCR amplification with 15 random primers produced 1935 bands, observed at 88 amplification loci; 77% of the amplified loci were polymorphic, with a mean of 4.5 polymorphic loci per primer. The similarity coefficient ranged from 0.5419 to 0.7933 among the 15 samples; the lowest value was between Manao (C. reticulata) and Feibai FR (C. japonica), and the largest value was between Chidan (C. japonica) and Yuanyang FG (C. japonica). Cluster analysis divided the 15 cultivars into two groups at the similarity coefficient of 0.65. A correlation was found between RAPD markers and petal color in the first group. No correlation was found between RAPD markers and the other traits (flower diameter, blooming period). This study provides information useful for the identification, classification, phylogenesis, and breeding of Camellia cultivars. 相似文献
999.
Zhou JP Zhu XP Zhang W Qin F Zhang SW Jia ZH 《Genetics and molecular research : GMR》2011,10(4):2511-2516
The most important traits of Chinese Liaoning cashmere goat fiber are fiber diameter, weight, and length. We looked for polymorphisms and their possible association with cashmere fiber traits in the 5' upstream region (5' UTR) of the prolactin receptor gene (PRLR), which encodes an anterior pituitary peptide hormone involved in different physiological activities; it is the principal endocrine regulator in pelage replacement in mammals. A novel single-nucleotide polymorphism (SNP) was found in the 5' UTR of PRLR by PCR-RFLP in an analysis of 590 goats. Two genotypes (CC and CT) were observed. The frequencies of allele C and T were 0.93 and 0.07, respectively. Association analysis revealed that the PRLR 5' UTR polymorphism (SNP5) was significantly associated with cashmere fiber weight and diameter. This novel SNP in hircine PRLR has potential as a molecular marker for cashmere fiber weight and diameter in Liaoning cashmere goats. 相似文献
1000.
The human liver is the largest organ in the body and has many important physiological functions. A global analysis of human liver proteins is essential for a better understanding of the molecular basis of the normal functions of the liver and of its diseases. As part of the Human Liver Proteome Project (HLPP), the goal of the present study was to visualize and detect as many proteins as possible in normal human livers using two-dimensional gel electrophoresis (2-DE). We have constructed a reference map of the proteins of human normal liver that can be used for the comprehensive analysis of the human liver proteome and other related research. To improve the resolution and enhance the detection of low abundance proteins, we developed and optimized narrow pH range ultra-zoom 2-DE gels. High resolution patterns of human liver in pH gradients 4.5–5.5, 5–6, 5.5–6.7, 6–9 and 6–11 are presented. To improve the poor resolution in the alkaline pH range of 2-DE gels, we optimized the isoelectric focusing protocol by including sample application using cup loading at the anode and incorporating 1.2% hydroxyethyl disulfide, 15% 2-propanol and 5% glycerol in the rehydration buffer. Using the optimized protocol, we obtained reproducibly better resolution in both analytical and preparative 2-DE gels. Compared with the 2386 and 1878 protein spots resolved in the wide range 3–10 and 4–7 pH gradients respectively, we obtained 5481 protein spots from the multiple (overlapping) narrow pH range ultra-zoom gels in the range of pH 4.5–9. The visualized reference map of normal human liver proteins presented in this paper will be valuable for comparative proteomic research of the liver proteome. 相似文献