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131.
Paria Pashazadeh‐Panahi Mohammad Hasanzadeh Reza Eivazzadeh‐Keihan 《Journal of molecular recognition : JMR》2020,33(5)
Ketoconazole or Nizoral is an antifungal medication used to treat various type of fungal infections. It has been reported that this antifungal agent is able to induce a variety of heart function side effects, such as long‐QT syndrome, and ventricular arrhythmias. Hence, prescribing, identifying and controlling the side effects of medications such as ketoconazole is essential for human safety. In this study, a distinct and fast colorimetric probe based on citrate capped silver nanoparticles (Cit‐AgNPs) was introduced for determination of trace amounts of ketoconazole. Cit‐AgNPs were synthesized trough a novel method and applied for the quantification of ketoconazole in human plasma samples. Ultraviolet‐visible spectroscopy, transmission electron microcopy, dynamic light scattering, and energy dispersive X‐ray spectroscopy analysis, have been utilized for characterization of Cit‐AgNPs. It was revealed that in the presence of ketoconazole, the absorption intensity of Cit‐AgNPs was decreased by increasing the ketoconazole concentration. Moreover, this reaction is accompanied by a color change from shiny yellow to brown/red in acidic pH. Under acidic pH and optimum condition, the calibration graph of the assay was linear in the range of 0.1 to 0.8 μM. According to the obtained results Cit‐AgNPs can be used as a novel probe for the sensitive and specific detection and determination of similar drugs in clinical samples. Also, this method open a new way to biomedical analyses of pharmaceutical samples which is necessary in TDM. 相似文献
132.
133.
Elham Davoudi-Dehaghani Ali Mohammad Foroughmand Babak Saffari Massoud Houshmand Hamid Galehdari Mehdi Shafa Shariat Panahi Majid Yavarian Mohammad Hossein Sanati Somayeh Torfi 《生物学前沿》2011,6(5):422-432
To investigate the genetic structure of human populations in the South-west region of Iran, mitochondrial first hypervariable
DNA sequences were obtained from 50 individuals representing three different ethnic groups from Khuzestan Province. Studied
groups were Shushtari Persians and Chahar Lang Bakhtiyaries from Indo-European-speaking populations and Bani Torof Arabs from
Semitic-speaking linguistic families. Genetic analysis of mtDNA data showed high similarity of Chahar Lang Bakhtiyaries with
other Iranian Indo-European-speaking populations while Shushtaries and Bani Torofs had a closer affinity with Semitic-speaking
groups rather than to other Iranian populations. The relationship of Chahar Lang Bakhtiyaries and Bani Torof Arabs with their
neighbor populations can be explained by linguistic and geographic proximity. Whereas, the greater similarity of Shushtari
Persians with West Asian Arabs is probably according to high gene flow between them. This article represents a preliminary
study of three major ethnic groups of South-west Iran which investigates the potential genetic substructure of the region. 相似文献
134.
Vinga S Carvalho AM Francisco AP Russo LM Almeida JS 《Algorithms for molecular biology : AMB》2012,7(1):10-12
Background
Chaos Game Representation (CGR) is an iterated function that bijectively maps discrete sequences into a continuous domain. As a result, discrete sequences can be object of statistical and topological analyses otherwise reserved to numerical systems. Characteristically, CGR coordinates of substrings sharing an L-long suffix will be located within 2 -L distance of each other. In the two decades since its original proposal, CGR has been generalized beyond its original focus on genomic sequences and has been successfully applied to a wide range of problems in bioinformatics. This report explores the possibility that it can be further extended to approach algorithms that rely on discrete, graph-based representations.Results
The exploratory analysis described here consisted of selecting foundational string problems and refactoring them using CGR-based algorithms. We found that CGR can take the role of suffix trees and emulate sophisticated string algorithms, efficiently solving exact and approximate string matching problems such as finding all palindromes and tandem repeats, and matching with mismatches. The common feature of these problems is that they use longest common extension (LCE) queries as subtasks of their procedures, which we show to have a constant time solution with CGR. Additionally, we show that CGR can be used as a rolling hash function within the Rabin-Karp algorithm.Conclusions
The analysis of biological sequences relies on algorithmic foundations facing mounting challenges, both logistic (performance) and analytical (lack of unifying mathematical framework). CGR is found to provide the latter and to promise the former: graph-based data structures for sequence analysis operations are entailed by numerical-based data structures produced by CGR maps, providing a unifying analytical framework for a diversity of pattern matching problems. 相似文献135.
Panahi M Alli Z Cheng X Belbaraka L Belgoudi J Sardana R Phipps J Altosaar I 《Transgenic research》2004,13(3):245-259
Human insulin-like growth factor-1 (hIGF-1) is a growth factor with clinical significance in medicine. The therapeutic potential
of recombinant hIGF-1 (rthIGF-1) stems from the fact that hIGF-1 resembles insulin in many aspects of physiology. The expression
of hIGF-1 in transgenic tobacco and rice plants using different expression cassettes is reported here. In the present study,
two coding sequences were tested, one with the original human sequence, but partially optimized for expression in E. coli and the other with a plant-codon-optimized sequence that was expected to give a higher level of expression in plant systems.
Three different hIGF-1 recombinant expression constructs were generated. All expression constructs utilized the maize ubiquitin
1 promoter with or without a signal sequence. Analyses conducted using a hIGF-1 specific ELISA kit showed all transgenic plants
produced hIGF-1 and the accumulated hIGF-1 increased from the E. coli codon bias to higher levels when the hIGF-1 coding sequence was codon-optimized to match that of the maize zeamatin protein
– the most transcribed gene in maize endosperm suspension cells. Further analyses that compared the functionality of the bacterial
signal peptide Lam B in plants showed that this leader peptide led to lower expression levels when compared to transgenic
plants that did not contain this sequence. This indicated that this expression construct was functional without removal of
the bacterial signal sequence. The maize ubiquitin 1 promoter was found to be more active in rice plants than tobacco plants
indicating that in this case, there was a class preference that was biased towards a monocot host. Biological analyses conducted
using protein extracts from transgenic plants showed that the rthIGF-1 was effective in stimulating the in vitro growth and proliferation of human SH-SY5Y neuroblastoma cells. This indicated that the plant-produced rthIGF-1 was stable
and biologically active. As some plants have been reported to express an endogenous insulin-like protein, we also looked for
any effect of the human growth factor in transgenic plants, but no developmental or morphological differences with wild type
tobacco or rice plants were detected. Since insulin and hIGF-1 share some overlapping roles, hIGF-1 may become a substitute
therapeutic agent in subjects with certain defects in their insulin receptor signaling. Hence, if the full beneficial potential
of rthIGF-1 is achieved, it is expected that in the future the demand will likely increase significantly. 相似文献
136.
Biological Activity of Human Granulocyte-Macrophage Colony Stimulating Factor is Maintained in a Fusion with Seed Glutelin Peptide 总被引:7,自引:3,他引:4
Sardana RK Alli Z Dudani A Tackaberry E Panahi M Narayanan M Ganz P Altosaar I 《Transgenic research》2002,11(5):521-531
Human granulocyte-macrophage colony stimulating factor (GM-CSF), a cytokine with many applications in clinical medicine, was produced specifically in the seeds of transgenic tobacco plants. Two rice endosperm-specific glutelin promoters of different size and sequence, Gt1 and Gt3, were used to direct expression. Also in the Gt3 construct, the GM-CSF coding region was in fusion with the first 24 nucleotides of the mature rice glutelin sequence at its 5' end. With the Gt1 construct plants, seed extracts contained the recombinant human GM-CSF protein up to a level of 0.03% of total soluble protein. Transgenic seed extracts actively stimulated the growth of human TF-1 cells suggesting that the seed-produced GM-CSF alone and in fusion with the rice glutelin peptide was stable and biologically active. Furthermore, native tobacco seed extracts inhibited the activity of E. coli-derived GM-CSF in this cytokine-dependent cell line. The seeds of F1 generation plants retained the biological activity of human GM-CSF protein indicating that the human coding sequence was stably inherited. The feasibility of oral delivery of such stable seed-produced cytokines is discussed. 相似文献
137.
138.
OI Klychnikov AV Drabkin OV Vasilenko YS Pavlov MS Trofimova IN Smolenskaya AA Rozenkranz AS Sobolev AV Babakov 《Biochemistry. Biokhimii?a》1998,63(9):1083-1089
Higher plant plasma membranes carry receptors of different affinity for the phytotoxin fusicoccin. Reception of fusicoccin involves proteins belonging to the highly conserved 14-3-3 family, but the complete structure of the fusicoccin receptor (FCR) is unknown. Using radiation inactivation analysis, we estimated the molecular masses of low-affinity and high-affinity FCR at 63 +/- 7 and 130 +/- 15 kD, respectively. The dose dependences of receptor inactivation indicate that microsomal specimens contain "silent" FCRs of 420 +/- 90 kD in amounts commensurate with that of the active FCRs. Both low- and high-affinity FCRs are inactivated by hydrolytic enzymes from the outer surface of the plasma membrane, and impairment of protoplast integrity causes an irreversible transition of the low-affinity binding site into the high-affinity one. A scheme is proposed for the organization of different types of FCR in the plasma membrane, implying that the membrane affinity for fusicoccin reflects the interaction between proteins in the FCR complex. 相似文献
139.
Biotinyl-oligosaccharides are a relatively new generation of saccharide
probes that enable immobilization of desired oligosaccharides on
streptavidin matrices for studies of carbohydrate-protein interactions.
Here we describe the facile preparation of biotinyl-l-3-(2-naphthyl)-
alanine hydrazide (BNAH) derivatives of oligosaccharides, containing a
strong UV absorbing and fluorescent group, in which the ring of the
reducing-end monosaccharide is nonreduced. We evaluate reactivities of
immobilized BNAH- N -glycans with plant lectins that recognize aspects of
the oligosaccharide core or outer-arms. We make some comparisons with
2-amino-6-amidobiotinyl-pyridine (BAP) derivatives obtained by reductive
amination, and 6-(biotinyl)-aminocaproyl-hydrazide (BACH) derivatives which
have a longer spacer-arm. N -Glycan-BNAH and-BAP derivatives have, overall,
comparable reactivities with lectins which recognize N -glycan outer-arms
or the trimannosyl core, but only BNAH and BACH derivatives are bound by
lectins which recognize the non- reduced core. Moreover, with Pisum sativum
agglutinin (PSA) which additionally requires the fucosyl- N-
glycan-asparaginyl core for high affinity binding, the immobilized BNAH
derivative (which is an alanine hydrazide beta-glycoside) can substitute
for the natural beta- glycosylasparaginyl core, whereas the BACH derivative
(aminocaproyl- hydrazide-beta-glycoside) is less effective. BNAH is a
derivatization reagent of choice, therefore, for solid phase
carbohydrate-binding experiments with immobilized N -glycans.
相似文献
140.
The core domain of retrotransposon integrase in Hordeum: predicted structure and evolution 总被引:1,自引:0,他引:1
Suoniemi A; Tanskanen J; Pentikainen O; Johnson MS; Schulman AH 《Molecular biology and evolution》1998,15(9):1135-1144
Propagation of long terminal repeat (LTR)-bearing retrotransposons and
retroviruses requires integrase (IN, EC 2.7.7.-), encoded by the
retroelements themselves, which mediates the insertion of cDNA copies back
into the genome. An active retrotransposon family, BARE-1, comprises
approximately 7% of the barley (Hordeum vulgare subsp. vulgare) genome. We
have generated models for the secondary and tertiary structure of BARE-1 IN
and demonstrate their similarity to structures for human immunodeficiency
virus 1 and avian sarcoma virus INs. The IN core domains were compared for
80 clones from 28 Hordeum accessions representative of the diversity of the
genus. Based on the structural model, variations in the predicted, aligned
translations from these clones would have minimal structural and functional
effects on the encoded enzymes. This indicates that Hordeum retrotransposon
IN has been under purifying selection to maintain a structure typical of
retroviral INs. These represent the first such analyses for plant INs.
相似文献