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61.
62.
Plants defend themselves against biotic or abiotic stress by triggering intracellular signaling pathways that regulate gene expression and responses to the offending agent. Phosphorylation and dephosphorylation represent major mechanisms for the regulation of plant defense pathways. Therefore, MAP kinases and phosphatases have been the focus of many studies in this area. This study identified three phosphatase activities, namely RcPPase I, II and III. Wounding increased the activity levels of RcPPase III, while the activities of RcPPase I and II remained constant compared to the control. N-terminal partial amino acid sequence, biochemical characterization with use of specific substrates and inhibitors indicated that the RcPPase III belong to the family of tyrosine phosphatases (PTPs). 相似文献
63.
64.
The present study examined the associations of sleep patterns with multiple measures of academic achievement of undergraduate university students and tested whether sleep variables emerged as significant predictors of subsequent academic performance when other potential predictors, such as class attendance, time devoted to study, and substance use are considered. A sample of 1654 (55% female) full-time undergraduates 17 to 25 yrs of age responded to a self-response questionnaire on sleep, academics, lifestyle, and well-being that was administered at the middle of the semester. In addition to self-reported measures of academic performance, a final grade for each student was collected at the end of the semester. Univariate analyses found that sleep phase, morningness/eveningness preference, sleep deprivation, sleep quality, and sleep irregularity were significantly associated with at least two academic performance measures. Among 15 potential predictors, stepwise multiple regression analysis identified 5 significant predictors of end-of-semester marks: previous academic achievement, class attendance, sufficient sleep, night outings, and sleep quality (R(2)=0.14 and adjusted R(2)=0.14, F(5, 1234)= 40.99, p < .0001). Associations between academic achievement and the remaining sleep variables as well as the academic, well-being, and lifestyle variables lost significance in stepwise regression. Together with class attendance, night outings, and previous academic achievement, self-reported sleep quality and self-reported frequency of sufficient sleep were among the main predictors of academic performance, adding an independent and significant contribution, regardless of academic variables and lifestyles of the students. 相似文献
65.
Ishii M Jorge SD de Oliveira AA Palace-Berl F Sonehara IY Pasqualoto KF Tavares LC 《Bioorganic & medicinal chemistry》2011,19(21):6292-6301
A series of 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazole derivatives was synthesized and their activity screened in vitro against Staphylococcus aureus, Trypanosoma cruzi, and Candida albicans. The bioactivity was expressed as minimum inhibitory concentration (MIC) for S. aureus strains, and as fifty-percent inhibitory concentration (IC(50)) of parasite population growth for T. cruzi. A molecular modeling approach was performed to establish qualitative relationships regarding the biological data and the compounds' physicochemical properties. The 5-(4-OC(4)H(9)Ph, 5l), and 5-(4-CO(2)CH(3)Ph, 5o) derivatives were the most active compounds for S. aureus ATCC 25923 (MIC=1.95-1.25 μg/mL) and T. cruzi (IC(50)=7.91 μM), respectively. Also, a preliminary evaluation against C. albicans involving some compounds was performed and the 5-(4-CH(3)Ph, 5e) derivative was the most active compound (MIC=3.28-2.95 μg/mL). In this preliminary study, all synthesized 3-acetyl-2,5-disubstituted-2,3-dihydro-1,3,4-oxadiazole derivatives were active against all microorganisms tested. 相似文献
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Moreira JS Almeida RG Tavares LS Santos MO Viccini LF Vasconcelos IM Oliveira JT Raposo NR Dias SC Franco OL 《The protein journal》2011,30(1):32-38
Heavy agricultural losses are closely related to attacks by insect-pests and phytopathogens such as bacteria and fungi. Among
them, the fungus Botrytis cinerea can cause gray mold in more than 200 different species of plants, and is considered a challenging problem for agribusiness.
Fungicides are commonly used to control this pathogen because they are fast-working and easy to apply. However, the continuous
use of fungicides may promote the selection of resistant fungi and can also cause profound contamination in ecosystems. Aiming
to find alternative strategies to solve these problems, several studies have focused on searching for plant proteins and peptides
with antifungal activities (AFPs). With this in mind, this report shows the isolation and characterization of two novels antifungal
proteins from flowers of rosemary pepper (Lippia sidoides Cham.) with 10 and 15 kDa. Isolation was performed by using an Octyl-Sepharose hydrophobic column. In vitro bioassays indicated
that isolated proteins were able to inhibit B. cinerea development, but were not effective against all bacteria tested. Moreover, N-termini sequences indicate that both proteins
showed sequence homology with NBS–LRR R proteins with a lower molecular mass, suggesting possible protein fragmentation. Data
reported here could help in the development of biotechnological products for crop protection against phytopathogenic fungi
in the near future. 相似文献
68.
Vera Teixeira Natacha Arede Rui Gardner Joaquín Rodríguez-León Ana T Tavares 《BMC developmental biology》2011,11(1):1-7
Background
Hemangioblasts are known as the common precursors for primitive hematopoietic and endothelial lineages. Their existence has been supported mainly by the observation that both cell types develop in close proximity and by in vitro differentiation and genetic studies. However, more compelling evidence will arise from tracking their cell fates using a lineage-specific marker.Results
We report the identification of a hemangioblast-specific enhancer (Hb) located in the cis-regulatory region of chick Cerberus gene (cCer) that is able to direct the expression of enhanced green fluorescent protein (eGFP) to the precursors of yolk sac blood and endothelial cells in electroporated chick embryos. Moreover, we present the Hb-eGFP reporter as a powerful live imaging tool for visualizing hemangioblast cell fate and blood island morphogenesis.Conclusions
We hereby introduce the Hb enhancer as a valuable resource for genetically targeting the hemangioblast population as well as for studying the dynamics of vascular and blood cell development. 相似文献69.
70.
Thirant C Bessette B Varlet P Puget S Cadusseau J Tavares Sdos R Studler JM Silvestre DC Susini A Villa C Miquel C Bogeas A Surena AL Dias-Morais A Léonard N Pflumio F Bièche I Boussin FD Sainte-Rose C Grill J Daumas-Duport C Chneiweiss H Junier MP 《PloS one》2011,6(1):e16375