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131.
Single-walled aluminum nitride nanotubes (AlNNTs) are introduced as an electronic sensor for detection of sulfur dioxide (SO(2)) molecules based on density functional theory calculations. The proposed sensor benefits from several advantages including high sensitivity: HOMO-LUMO energy gap of the AlNNT is appreciably sensitive toward the presence of SO(2) so that it decreases from 4.11?eV in the pristine tube to 1.01?eV in the SO(2)-adsorbed form, pristine application: this nanotube can detect the SO(2) molecule in its pristine type without manipulating its structure through doping, chemical functionalization, making defect, etc., short recovery time: the adsorption energy of SO(2) molecule is not so large to hinder the recovery of AlNNTs and therefore the sensor will possess short recovery times, and good selectivity: the tube can selectively detect the SO(2) molecule in the presence of several molecules such as H(2)O, CO, NH(3), HCOH, CO(2), N(2), and H(2). 相似文献
132.
133.
Kashanian S Askari S Ahmadi F Omidfar K Ghobadi S Tarighat FA 《DNA and cell biology》2008,27(10):581-586
The interaction of native calf thymus DNA with clodinafop-propargyl (CP), in 10 mM HEPES aqueous solutions at neutral pH 7.2, has been investigated by spectrophotometric, circular dichroism (CD), spectrofluorometric, melting temperature (Tm), and viscosimetric techniques. It was found that CP molecules could intercalate between base pairs of DNA as evidenced by hyperchromism in UV absorption band of DNA, an increase in melting temperature, a sharp increase in specific viscosity of DNA, induced CD spectral changes, and increase in the fluorescence of methylene blue (MB)-DNA solutions in the presence of increasing amounts of CP, which indicates that it is able to release the intercalated MB completely. All results suggest that the CP interacts with calf thymus DNA by an intercalative mode of binding. 相似文献
134.
Meshginqalam Bahar Ahmadi Mohammad Taghi Ismail Razali Sabatyan Arash 《Plasmonics (Norwell, Mass.)》2017,12(6):1991-1997
Plasmonics - Surface plasmon resonance (SPR)-based biosensing is an accurate and sensitive technique used to evaluate the biomolecular interactions in real time in a label-free environment. Several... 相似文献
135.
Increased production of yersiniabactin and an anthranilate analog through media optimization 下载免费PDF全文
Nicholas Moscatello Ruiquan Qi Mahmoud Kamal Ahmadi Blaine A. Pfeifer 《Biotechnology progress》2017,33(5):1193-1200
Yersiniabactin (Ybt) is a mixed nonribosomal peptide‐polyketide natural product that binds a wide range of metals with the potential to impact processes requiring metal retrieval and removal. In this work, we substantially improved upon the heterologous production of Ybt and an associated anthranilate analog through systematic screening and optimization of culture medium components. Specifically, a Plackett‐Burman design‐of‐experiments methodology was used to screen 22 components and to determine those contributing most to siderophore production. L‐cysteine, L‐serine, glucose, and casamino acids significantly contributed to the production of both compounds. Using this approach together with metabolic engineering of the base biosynthetic process, Ybt and the anthranilate analog titers were increased to 867 ± 121 mg/L and 16.6 ± 0.3 mg/L, respectively, an increase of ~38 and ~79‐fold relative to production in M9 medium. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:1193–1200, 2017 相似文献
136.
Seeds of Bunium persicum (Boiss.) B. Fedtsch. have complex physiological dormancy that can be released by 15 weeks stratification. The present study revealed that cold stratification enhanced content of H2O2, O2 -· and application of GA3 and ROS donors (Fenton reagent, H2O2, methylviologen and menadione) did not affect or only slightly promoted the germination of non-stratified, fully dormant seeds. Dormancy was markedly decreased by ROS-generating reagents, GA3 and fluridone (an inhibitor of ABA biosynthesis) and was enhanced by ROS-decreasing compounds (DMTU, Tiron, SB and DPI), diniconazole (Dinc, an inhibitor of ABA catabolism) and paclobutrazol (PAC, an inhibitor of GA biosynthesis) when dormancy was partially removed by cold stratification. The response to these compounds reduced with increasing time of stratification. ABA inhibited germination by repressing of NADPH oxidase activity and ROS accumulation and conversely, GA triggered germination by promoting an increase of NADPH oxidase activity and ROS levels. Data in this study, for the first time suggest releasing deep complex physiological dormancy by cold stratification is associated with interplay between ROS and ABA/GA. 相似文献
137.
Qoorchi Moheb Seraj Farid Heravi-Faz Niloofar Soltani Arash Ahmadi Seyed Sajad shahbeiki Fatemeh Talebpour Amir Afshari Amir R. Ferns Gordon A. Bahrami Afsane 《Molecular biology reports》2022,49(10):9623-9632
Molecular Biology Reports - Thymol (2-isopropyl-5-methylphenol) is a colorless crystalline derivative of cymene, that possesses pleotropic pharmacological properties, including analgesic,... 相似文献
138.
Mahboobi Mahdieh Sedighian Hamid Malekara Ehsan Khalili Saeed Rahbar Mohammad Reza Ahmadi Zanoos Kobra Halabian Raheleh Jahangiri Abolfazl 《International journal of peptide research and therapeutics》2021,27(2):1019-1026
International Journal of Peptide Research and Therapeutics - Epsilon toxin (ETX) is one of four lethal toxins of Clostridium perfringens produced by types B and D of the pathogen. This pore-forming... 相似文献
139.
Hanieh Mohajjel Shoja Laleh Ahmadi Maryam Kolahi Elham Mohajel Kazemi 《Physiology and Molecular Biology of Plants》2021,27(9):2071
Rapid commercialization, industrialization and the use of nanotechnology has led to an increase in the distribution of nanoparticles (NPs) in the environment. The most common metal oxide NPs which is present within products is Titanium dioxide (TiO2). TiO2 NPs have photocatalytic nature and can affect plant growth. The current study investigated the morphological, anatomical and biochemical features of Baby sun rose (Aptenia cordifolia) after exposure to different concentrations of TiO2 nanoparticles (0, 1, 5, 10 and 20 mg L−1). Treatment with TiO2 NPs showed changes in the morphological features and increased photosynthetic pigmentation within the plant. An increase in the level of phenolics (12%) and flavonoid compounds (13%) was observed when plants were treated with moderate levels of TiO2 NPs. A reduction in the diameter of the vascular bundles and increased thickening of the transverse wall were observed in several samples. The number of scattered vascular bundles in the stems increased. The morphological, biochemical, and anatomical responses of Baby sun rose indicates that plants can adapt to environments contaminated with up to 20 mg L−1 TiO2 NPs. The cultivation of Baby sun rose plants in environments polluted with TiO2 NPs is recommended. This study enhances the knowledge of the effect of TiO2 NPs on the growth of Baby sun rose which is an ornamental plant, widely cultivated in different regions of Iran. The results of this study suggest that contaminated environments up to 20 mg L−1 TiO2 NPs can be managed by phytoremediation. Further studies are needed to investigate this plant''s tolerance strategies against stress caused by TiO2 NPs and bulk TiO2 as well as the effect of other nanoparticles on plant. 相似文献
140.
To investigate the comparative abilities of six different bioclimatic models in an independent area, utilizing the distribution of eight different species available at a global scale and in Australia. Global scale and Australia. We tested a variety of bioclimatic models for eight different plant species employing five discriminatory correlative species distribution models (SDMs) including Generalized Linear Model (GLM), MaxEnt, Random Forest (RF), Boosted Regression Tree (BRT), Bioclim, together with CLIMEX (CL) as a mechanistic niche model. These models were fitted using a training dataset of available global data, but with the exclusion of Australian locations. The capabilities of these techniques in projecting suitable climate, based on independent records for these species in Australia, were compared. Thus, Australia is not used to calibrate the models and therefore it is as an independent area regarding geographic locations. To assess and compare performance, we utilized the area under the receiver operating characteristic (ROC) curves (AUC), true skill statistic (TSS), and fractional predicted areas for all SDMs. In addition, we assessed satisfactory agreements between the outputs of the six different bioclimatic models, for all eight species in Australia. The modeling method impacted on potential distribution predictions under current climate. However, the utilization of sensitivity and the fractional predicted areas showed that GLM, MaxEnt, Bioclim, and CL had the highest sensitivity for Australian climate conditions. Bioclim calculated the highest fractional predicted area of an independent area, while RF and BRT were poor. For many applications, it is difficult to decide which bioclimatic model to use. This research shows that variable results are obtained using different SDMs in an independent area. This research also shows that the SDMs produce different results for different species; for example, Bioclim may not be good for one species but works better for other species. Also, when projecting a “large” number of species into novel environments or in an independent area, the selection of the “best” model/technique is often less reliable than an ensemble modeling approach. In addition, it is vital to understand the accuracy of SDMs' predictions. Further, while TSS, together with fractional predicted areas, are appropriate tools for the measurement of accuracy between model results, particularly when undertaking projections on an independent area, AUC has been proved not to be. Our study highlights that each one of these models (CL, Bioclim, GLM, MaxEnt, BRT, and RF) provides slightly different results on projections and that it may be safer to use an ensemble of models. 相似文献