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101.
Mozafari Hadi Khatami Shohreh Kiani Amir Rahimi Zohreh Vaisi-Raygani Asad Afsharnaderi Azam Alaei Mohammad Reza 《Biological trace element research》2020,193(1):130-137
Biological Trace Element Research - Gaucher disease (GD) is most frequent disorder of glycolipid storage. The glucosylceramide accumulation might lead to oxidative stress and changes in lipid... 相似文献
102.
Farzan SF Palermo LM Yokoyama CC Orefice G Fornabaio M Sarkar A Kellogg GE Greengard O Porotto M Moscona A 《The Journal of biological chemistry》2011,286(44):37945-37954
Paramyxoviruses, including the childhood pathogen human parainfluenza virus type 3, enter host cells by fusion of the viral and target cell membranes. This fusion results from the concerted action of its two envelope glycoproteins, the hemagglutinin-neuraminidase (HN) and the fusion protein (F). The receptor-bound HN triggers F to undergo conformational changes that render it competent to mediate fusion of the viral and cellular membranes. We proposed that, if the fusion process could be activated prematurely before the virion reaches the target host cell, infection could be prevented. We identified a small molecule that inhibits paramyxovirus entry into target cells and prevents infection. We show here that this compound works by an interaction with HN that results in F-activation prior to receptor binding. The fusion process is thereby prematurely activated, preventing fusion of the viral membrane with target cells and precluding viral entry. This first evidence that activation of a paramyxovirus F can be specifically induced before the virus contacts its target cell suggests a new strategy with broad implications for the design of antiviral agents. 相似文献
103.
Achawanantakun R Sun Y Takyar SS 《Journal of bioinformatics and computational biology》2011,9(2):317-337
Many noncoding RNAs (ncRNAs) function through both their sequences and secondary structures. Thus, secondary structure derivation is an important issue in today's RNA research. The state-of-the-art structure annotation tools are based on comparative analysis, which derives consensus structure of homologous ncRNAs. Despite promising results from existing ncRNA aligning and consensus structure derivation tools, there is a need for more efficient and accurate ncRNA secondary structure modeling and alignment methods. In this work, we introduce a consensus structure derivation approach based on grammar string, a novel ncRNA secondary structure representation that encodes an ncRNA's sequence and secondary structure in the parameter space of a context-free grammar (CFG) and a full RNA grammar including pseudoknots. Being a string defined on a special alphabet constructed from a grammar, grammar string converts ncRNA alignment into sequence alignment. We derive consensus secondary structures from hundreds of ncRNA families from BraliBase 2.1 and 25 families containing pseudoknots using grammar string alignment. Our experiments have shown that grammar string-based structure derivation competes favorably in consensus structure quality with Murlet and RNASampler. Source code and experimental data are available at http://www.cse.msu.edu/~yannisun/grammar-string. 相似文献
104.
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106.
Ariaeenejad S Habibi-Rezaei M Jamili S Fatemi MR Poursasan N Ahmad F Sheibani N Kavousi K Moosavi-Movahedi AA 《Cell biochemistry and biophysics》2012,62(1):73-81
Hemoglobin (Hb) variability is a commonly used index of phylogenetic differentiation and molecular adaptation in fish enabling
them to adapt to different ecological conditions. In this study, the characteristics of Hbs from two Sturgeon species of the
Southern Caspian Sea Basin were investigated. After extraction and separation of hemoglobin from whole blood, the polyacrylamide
gel electrophoresis (SDS-PAGE), cellulose acetate electrophoresis, and isoelectric focusing (IEF) were used to confirm Hb
variabilities in these fishes. We showed that although both species have variable Hbs with different isoelectric points, their
dominant Hbs can be identified. Ion exchange on CM-cellulose chromatography was used for purification of the dominant Hbs
from these fishes. The accuracy of the methods was confirmed by IEF and SDS-PAGE. Spectral studies using fluorescence spectrophotometery
indicated that although the Hbs from these fishes had similar properties they exhibited clear differences with human Hb. A
comparative study of Hbs alpha-helix secondary substructures was performed by circular dichroism spectropolarimetry (CD) analysis.
UV–vis spectrophotometery was also utilized to measure oxygen affinity of Hbs by sodium dithionite. Oxygen affinities of these
Hbs were compared using Hb–oxygen dissociation curves. Together, these results demonstrate a significant relationship between
oxygen affinity of fish hemoglobins and environmental partial pressure of oxygen. 相似文献
107.
Majid Salehi Zohreh Bagher Seyed Kamran Kamrava Arian Ehterami Rafieh Alizadeh Mohammad Farhadi Masoumeh Falah Ali Komeili 《Journal of cellular physiology》2019,234(9):15357-15368
Regeneration and functional recovery after peripheral nerve damage still remain a significant clinical problem. In this study, alginate/chitosan (alg/chit) hydrogel was used for the transplantation of olfactory ectomesenchymal stem cells (OE-MSCs) to promote peripheral nerve regeneration. The OE-MSCs were isolated from olfactory mucosa biopsies and evaluated by different cell surface markers and differentiation capacity. After creating sciatic nerve injury in a rat model, OE-MSCs were transplanted to the injured area with alg/chit hydrogel which was prepared and well-characterized. The prepared hydrogel had the porosity of 91.3 ± 1.27%, the swelling ratio of 379% after 240 min, weight loss percentages of 80 ± 5.56% after 14 days, and good blood compatibility. The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, 4′,6-diamidino-2-phenylindole, and LIVE/DEAD staining were done to assay the behavior of OE-MSCs on alg/chit hydrogel and the results confirmed that the hydrogel can provide a suitable substrate for cell survival. For functional analysis, alg/chit hydrogel with and without OE- MSCs was injected into a 3-mm sciatic nerve defect of Wistar rats. The results of the sciatic functional index, hot plate latency, electrophysiological assessment, weight-loss percentage of wet gastrocnemius muscle, and histopathological examination using hematoxylin–eosin and Luxol fast blue staining showed that utilizing alg/chit hydrogel with OE-MSCs to the sciatic nerve defect enhance regeneration compared to the control group and hydrogel without cells. 相似文献
108.
2-Acetylaminofluorene (2-AAF) is a carcinogenic and mutagenic derivative of fluorene. It is used as a biochemical tool in the study of carcinogenesis. Studies have shown that it induces tumors in a number of species in the liver, bladder, and kidney. It is thought that 2-AAF-DNA adduct formation leads to mutation, and eventually tumor formation. The aim of this study was to examine the interactions of AAF with calf-thymus DNA in aqueous solution at physiological conditions, using constant DNA concentration (12.5 mM) and various AAF/polynucleotide (phosphate) ratios of 1/120, 1/80, 1/40, 1/20, 1/10, 1/5, 1/2, and 1/1. Fourier transform infrared and UV-visible spectroscopic methods and molecular modeling were used to determine the ligand binding mode, the binding constant, and the stability of AAF-DNA complexes in aqueous solution. Spectroscopic evidence showed both intercalation and external binding of AAF to DNA with an overall binding constant of K(AAF-DNA) = 2.33 × 10(7) M(-1). 2-AAF induced a partial B to A-DNA transition and DNA aggregation was observed at high AAF content. 相似文献
109.
K. Ghassemi-Golezani N. Farhadi N. Nikpour-Rashidabad 《Plant Cell, Tissue and Organ Culture》2018,133(2):237-248
Drought stress is a major threat to plant production in semi-arid and arid areas of the world. This research was laid out to asses the effects of sodium nitroprusside (SNP) as a nitric oxide donor on growth, physiological and biochemical changes of in vitro-cultured Allium hirtifolium under polyethylene glycol (PEG) induced drought stress. Basal plate explants of A. hirtifolium were cultured on MS medium containing different levels of PEG (0, 2, 4, 8 and 16 mM) and SNP (0, 10, 40 and 70 µM). After prolonged drought, growth responses, oxidative stress indicators, and phytochemical variations of regenerated plantlets with or without PEG and/or SNP treatments were recorded. Water limitation reduced regeneration potential of explants and consequently number of shoots per explant. Relative water content, total chlorophyll and carotenoid contents of regenerated A. hirtifolium plantlets decreased, but accumulation of malondialdehyde, H2O2 and proline and the activities of superoxide dismutase, ascorbate peroxidase, catalase and peroxidase enzymes increased with decreasing water availability. Total phenol and allicin contents were also increased in response to drought stress. Exogenous SNP in 10 and particularly in 40 µM was effective in enhancing regeneration rate and relative water content as well as protecting photosynthetic pigments under different levels of water availability. SNP also inhibited the hydrogen peroxide (H2O2) accumulation and lipid peroxidation in cell membranes via increasing the activities of superoxide dismutase and ascorbate peroxidase enzymes and accumulating proline and allicin. In general, these results suggest that exogenous SNP at 40 µM not only could somewhat protect A. hirtifolium from drought stress, but also can help to improve the propagation and allicin production of that plant under in vitro condition. 相似文献
110.
Abdoulreza Agheli Mansour Seyed Latif Mousavi Iraj Rasooli Shahram Nazarian Jafar Amani Nima Farhadi 《Biologicals》2010,38(2):260-264
Botulinum neurotoxins (BoNTs) inhibit neurotransmitter release from peripheral cholinergic synapses. BoNTs consist of a toxifying light chain and a heavy chain (HC) linked through a disulfide bond. In the present study we explored the immunogenicity and protective capability of the most effective part corresponding to 1163-1256 residues of botulinum type E neurotoxin HC gene. DNA encoding the 93 C-terminal amino acid of HC residues was synthesized with optimal codon usage for expression. These DNA fragments were ligated into a pLivSelect vector and subcloned into expression vector pET32a. Recombinant plasmids were then transformed into Escherichia coli strain BL21 DE3. The recombinant protein was purified by nickel affinity gel column chromatography. The HC1163-1256 was identified by antibodies raised against BoNT/E. HC1163-1256 was shown to bind with synaptotagmin and gangliosides, indicating that the expressed and purified HC1163-1256 protein retains a functionally active conformation. The immunization with recombinant protein induced a protection level in mice. The immunization with 2 μg of the recombinant protein induced a significant protection level in mice. In conclusion, availability of the recombinant protein provides an effective system to study the biochemical and physical interactions involved during BoNT binding to nerve cells and protection against its toxicity. 相似文献