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921.
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923.
Length–weight relationships (LWRs) were evaluated for Jinshaia sinensis (Sauvage & Dabry de Thiersant, 1874) and Lepturichthys fimbriata (Günther, 1888) using a total of 289 specimens caught by gill nets (mesh size 5.0 cm) and angling in the Yalong River, southwestern China during February and March 2007. This study presents the first reference on LWR for these species from the Yalong River. 相似文献
924.
X. Shi W. Jiang S. Ye M. Duan G. Liu X. Hu D. Liu 《Zeitschrift fur angewandte Ichthyologie》2016,32(6):1303-1304
Length–weight relationships (LWRs) were determined for three endemic fish species [Gobiobotia filifer (Garman, 1912), Homatula potanini (Günther, 1896) and Xenophysogobio boulengeri (Tchang, 1929)] from the Yangtze River in China. Samples were obtained between April 2008 and June 2012 using various types of fishing gear and electroshock fishing techniques. For each species, the sample size, length range, weight range, LWR, 95% confidence intervals of a and b, and coefficient of correlation were determined. Prior to this study, the LWRs for two species [Gobiobotia filifer (Garman, 1912) and Homatula potanini (Günther, 1896)] were unknown. 相似文献
925.
Pyrophosphate: fructose-6-phosphate 1-phosphotransferase (PFP) regulates carbon metabolism during grain filling in rice 总被引:1,自引:0,他引:1
Erchao Duan Yihua Wang Linglong Liu Jianping Zhu Mingsheng Zhong Huan Zhang Sanfeng Li Baoxu Ding Xin Zhang Xiuping Guo Ling Jiang Jianmin Wan 《Plant cell reports》2016,35(6):1321-1331
Key message
Decreased PFPase activity in rice perturbs the equilibration of carbon metabolism during grain filling but has no visible phenotypic effects during the vegetative and reproductive growth stages.Abstract
Starch is a primary energy reserve for various metabolic processes in plant. Despite much advance has been achieved in pathways involved in starch biosynthesis, information was still lacked for precise regulation related to carbon metabolism during seed filling in rice (Oryza sativa). The objective of this study was to identify and characterize new gene associated with carbon metabolism during grain filling. By screening our chemical mutant pool, two allelic mutants exhibiting floury endosperm were isolated. No visible phenotypic defects were observed during both the vegetative and reproductive growth stages, except for the floury-like endosperm of grains with significantly reduced kernel thickness, 1000-grain weight and total starch content. Map-based cloning revealed that the mutant phenotypes were controlled by a gene encoding pyrophosphate: fructose-6-phosphate 1-phosphotransferase (PFP, EC 2.7.1.90) β subunit (PFPβ), which catalyzes reversible interconversion between fructose-6-phosphate and fructose-1, 6-bisphosphate. The identity of PFP β was further confirmed by a genetic complementation test. Subcellular analysis demonstrated that PFPβ was localized in cytoplasm. Quantitative PCR and histochemical staining indicated PFP β was ubiquitously expressed in various tissues. Furthermore, we found PFP β could express in both the early and late phases of starch accumulation during grain filling and decreased activity of PFP β in pfp mutants resulted in compromised carbon metabolism with increased soluble sugar contents and unfavorable starch biosynthesis. Our results highlight PFPβ functions in modulating carbon metabolism during grain filling stage.926.
927.
Genotypes of Cryptosporidium spp. and Enterocytozoon bieneusi in Human Immunodeficiency Virus‐Infected Patients in Lagos,Nigeria
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Oladele T. Ojuromi Liping Duan Fernando Izquierdo Soledad M. Fenoy Wellington A. Oyibo Carmen del Aguila Anofi O. T. Ashafa Yaoyu Feng Lihua Xiao 《The Journal of eukaryotic microbiology》2016,63(4):414-418
Molecular characterization of Cryptosporidium spp. and Enterocytozoon bieneusi has improved our understanding of the transmission of both organisms in humans. In this study, to infer possible infection sources, Cryptosporidium spp. and E. bieneusi in fecal specimens from 90 HIV‐infected patients attending antiretroviral clinics in Lagos, Nigeria were detected and genotyped by PCR and DNA sequencing. Cryptosporidium spp. and E. bieneusi were identified in four and five patients, respectively, including the occurrence of subtype IeA11T3G3 of Cryptosporidium hominis in two patients, subtype IIcA5G3k of Cryptosporidium parvum in one patient, and Type IV of E. bieneusi in four patients. Among the remaining positive patients, one had mixed infection of Cryptosporidium meleagridis and C. hominis and one had mixed E. bieneusi genotypes. These data highlight a possible difference in major transmission routes (anthroponotic vs. zoonotic) between Cryptosporidium spp. and E. bieneusi in HIV+ patients in the study area. 相似文献
928.
Chemical and Genetic Comparative Analysis of Gentiana crassicaulis and Gentiana macrophylla
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Gentiana crassicaulis Duthie ex Burk . and Gentiana macrophylla Pall . are two main sources of Radix Gentianae Macrophyllae (Qinjiao) available in markets, which has a wide range of anti‐inflammatory effects and has been extensively used for fighting rheumatoid arthritis. However, they vary in terms of chemical compositions, pharmacological activities, and biomass. In this study, a combined chemical and genetic (HPLC and DNA barcoding) approach was used to compare these two plants. Four predominant bioactive compounds, namely, gentiopicroside, loganic acid, swertiamarin, and sweroside, were used to assess the chemical variations. Based on chemical variations, 15 samples were clustered into two groups through PCA analyses. DNA barcoding utilizing the variable nuclear ITS2 regions were sequenced, aligned, and compared. Together with 61 sequences collected from GenBank, 76 batches of Qinjiao were clustered in two groups according to species origin. The genetic relationships indicated by the ITS2‐based NJ tree were consistent with the chemical variations. Thus, the chemical profiles determined by HPLC and DNA profiles obtained from ITS2 region could be applied for the quality control of Qinjiao. 相似文献
929.
Eric C. Leuthardt Chong Duan Michael J. Kim Jian L. Campian Albert H. Kim Michelle M. Miller-Thomas Joshua S. Shimony David D. Tran 《PloS one》2016,11(2)
Background
Poor central nervous system penetration of cytotoxic drugs due to the blood brain barrier (BBB) is a major limiting factor in the treatment of brain tumors. Most recurrent glioblastomas (GBM) occur within the peritumoral region. In this study, we describe a hyperthemic method to induce temporary disruption of the peritumoral BBB that can potentially be used to enhance drug delivery.Methods
Twenty patients with probable recurrent GBM were enrolled in this study. Fourteen patients were evaluable. MRI-guided laser interstitial thermal therapy was applied to achieve both tumor cytoreduction and disruption of the peritumoral BBB. To determine the degree and timing of peritumoral BBB disruption, dynamic contrast-enhancement brain MRI was used to calculate the vascular transfer constant (Ktrans) in the peritumoral region as direct measures of BBB permeability before and after laser ablation. Serum levels of brain-specific enolase, also known as neuron-specific enolase, were also measured and used as an independent quantification of BBB disruption.Results
In all 14 evaluable patients, Ktrans levels peaked immediately post laser ablation, followed by a gradual decline over the following 4 weeks. Serum BSE concentrations increased shortly after laser ablation and peaked in 1–3 weeks before decreasing to baseline by 6 weeks.Conclusions
The data from our pilot research support that disruption of the peritumoral BBB was induced by hyperthemia with the peak of high permeability occurring within 1–2 weeks after laser ablation and resolving by 4–6 weeks. This provides a therapeutic window of opportunity during which delivery of BBB-impermeant therapeutic agents may be enhanced.Trial Registration
ClinicalTrials.gov NCT01851733相似文献930.