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121.
Sanaii Ahmad Shirzad Hedayatollah Haghighian Mehrnoosh Rahimian Ghorbanali Soltani Amin Shafigh Mohammadhadi Tahmasbi Kamran Bagheri Nader 《Molecular biology reports》2019,46(6):5703-5712
Molecular Biology Reports - Helicobacter pylori (H. pylori) has been shown to be one of the leading causes of peptic ulcer diseases (PUDs) and gastritis. T helper-22 (Th22) cells and its... 相似文献
122.
Zohreh Firouzi Parisa Lari Marzieh Rashedinia Mohammad Ramezani Mehrdad Iranshahi Khalil Abnous 《Life sciences》2014
Aims
Curcumin is one of the most important constituent of Curcuma longa L. with antioxidant, anti-inflammatory and anticancer effects. In this study, we investigated potential intracellular targets of curcumin by affinity chromatography based on target deconvolution. Identification of curcumin interacting proteins may help in evaluating biological and side effects of this natural compound.Main methods
Curcumin was immobilized through a linker to sepharose beads as solid matrix. Pull down assay was performed by passing tissue lysate of mouse brain through the column to enrich and purify curcumin interacting proteins. Then proteins were separated using two-dimensional gel electrophoresis and identified using MALDI/TOF/TOF mass spectrometry.Key findings
Our results show that curcumin physically binds to a wide range of cellular proteins including structural proteins, metabolic enzymes and proteins involved in apoptosis pathway.Significance
Finding curcumin interacting proteins may help in understanding a part of curcumin pharmacological effects. 相似文献123.
Comparison of different protocols for neural differentiation of human induced pluripotent stem cells
Ali Salimi Samad Nadri Marzieh Ghollasi Khosro Khajeh Masoud Soleimani 《Molecular biology reports》2014,41(3):1713-1721
Although embryonic stem cells (ESCs) have enormous potentials due to their pluripotency, their therapeutic use is limited by ethical, biological and safety issues. Compared to ESCs, induced pluripotent stem cells (iPSCs) can be obtained from mouse or human fibroblasts by reprogramming. Numerous studies have established many protocols for differentiation of human iPSCs (hiPSCs) into neural lineages. However, the low differentiation efficiency of such protocols motivates researchers to design new protocols for high yield differentiation. Herein, we compared neural differentiation potential of three induction media for conversion of hiPSCs into neural lineages. In this study, hiPSCs-derived embryoid bodies were plated on laminin coated dishes and were treated with three induction media including (1) bFGF, EGF (2) RA and (3) forskolin, IBMX. Immunofluorescence staining and quantitative real-time PCR (qPCR) analysis were used to detect the expression of neural genes and proteins. qPCR analysis showed that the expression of neural genes in differentiated hiPSCs in forskolin, IBMX supplemented media was significantly higher than undifferentiated cells and those in induction media containing bFGF, EGF or RA. In conclusion, our results indicated a successful establishment protocol with high efficiency for differentiation of hiPSCs into neural lineages. 相似文献
124.
Raheleh Roudi Zahra Madjd Marzieh Ebrahimi Fazel Sahraneshin Samani Ali Samadikuchaksaraei 《Cellular & molecular biology letters》2014,19(1):23-36
Cancer stem cells (CSCs) are subpopulations of tumor cells that are responsible for tumor initiation, maintenance and metastasis. Recent studies suggested that lung cancer arises from CSCs. In this study, the expression of potential CSC markers in cell line A549 was evaluated. We applied flow cytometry to assess the expression of putative stem cell markers, including aldehyde dehydrogenase 1 (ALDH1), CD24, CD44, CD133 and ABCG2. Cells were then sorted according to the expression of CD44 and CD24 markers by fluorescence-activated cell sorting (FACS) Aria II and characterized using their clonogenic and sphere-forming capacity. A549 cells expressed the CSC markers CD44 and CD24 at 68.16% and 54.46%, respectively. The expression of the putative CSC marker ALDH1 was 4.20%, whereas the expression of ABCG2 and CD133 was 0.93%. Double-positive CD44/133 populations were rare. CD44+/24+ and CD44+/CD24?/low subpopulations respectively exhibited 64% and 27.92% expression. The colony-forming potentials in the CD44+/CD24+ and CD44+/CD24?/low subpopulations were 84.37 ± 2.86% and 90 ± 3.06%, respectively, while the parental A549 cells yielded 56.65 ± 2.33% using the colony-formation assay. Both isolated subpopulations formed spheres in serumfree medium supplemented with basic fibroblast growth factor (bFGF) and epidermal growth factor (EGF). CD44 and CD24 cannot be considered potential markers for isolating lung CSCs in cell line A549, but further investigation using in vivo assays is required. 相似文献
125.
Andrzej K Noyszewski Farhad Ghavami Loai M Alnemer Ali Soltani Yong Q Gu Naxin Huo Steven Meinhardt Penny MA Kianian Shahryar F Kianian 《BMC genomics》2014,15(1)
Background
Wheat is an excellent plant species for nuclear mitochondrial interaction studies due to availability of large collection of alloplasmic lines. These lines exhibit different vegetative and physiological properties than their parents. To investigate the level of sequence changes introduced into the mitochondrial genome under the alloplasmic condition, three mitochondrial genomes of the Triticum-Aegilops species were sequenced: 1) durum alloplasmic line with the Ae. longissima cytoplasm that carries the T. turgidum nucleus designated as (lo) durum, 2) the cytoplasmic donor line, and 3) the nuclear donor line.Results
The mitochondrial genome of the T. turgidum was 451,678 bp in length with high structural and nucleotide identity to the previously characterized T. aestivum genome. The assembled mitochondrial genome of the (lo) durum and the Ae. longissima were 431,959 bp and 399,005 bp in size, respectively. The high sequence coverage for all three genomes allowed analysis of heteroplasmy within each genome. The mitochondrial genome structure in the alloplasmic line was genetically distant from both maternal and paternal genomes. The alloplasmic durum and the Ae. longissima carry the same versions of atp6, nad6, rps19-p, cob and cox2 exon 2 which are different from the T. turgidum parent. Evidence of paternal leakage was also observed by analyzing nad9 and orf359 among all three lines. Nucleotide search identified a number of open reading frames, of which 27 were specific to the (lo) durum line.Conclusions
Several heteroplasmic regions were observed within genes and intergenic regions of the mitochondrial genomes of all three lines. The number of rearrangements and nucleotide changes in the mitochondrial genome of the alloplasmic line that have occurred in less than half a century was significant considering the high sequence conservation between the T. turgidum and the T. aestivum that diverged from each other 10,000 years ago. We showed that the changes in genes were not limited to paternal leakage but were sufficiently significant to suggest that other mechanisms, such as recombination and mutation, were responsible. The newly formed ORFs, differences in gene sequences and copy numbers, heteroplasmy, and substoichiometric changes show the potential of the alloplasmic condition to accelerate evolution towards forming new mitochondrial genomes.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-67) contains supplementary material, which is available to authorized users. 相似文献126.
Mozhgan Soltani Kazem Parivar Javad Baharara Mohammad Amin Kerachian Javad Asili 《Reports of Biochemistry & Molecular Biology》2014,3(1):43-50
Background:
Holothuroids (sea cucumbers) are members of the phylum echinodermata, which produce saponins. Saponins exhibit a wide spectrum of pharmacological and biological activities. In this study, we isolated the crude saponins from the body wall of the dominant Iranian species of sea cucumber, Holothuria leucospilota (H. leucospilota). The purpose of this study was to confirm the presence of saponins in the Persian Gulf H. leucospilota and study the hemolytic and cytotoxic activities of these compounds.Methods:
The body wall of sea cucumber was dried and powdered and the crude saponins were isolated using various solvents. The crude saponins were further purified by column chromatography using HP-20 resin. The foam test, Thin Layer Chromatography (TLC), hemolytic assay, and Fourier Transform Infrared Spectroscopy (FTIR) confirmed the presence of saponins. Cytotoxicity was analyzed using a 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay on A549 cells, a human lung cancer cell line.Results:
The foam test, hemolytic assay, and TLC supported the presence of saponin compounds in the 80% ethanol fraction of H. leucospilota. The infrared (IR) spectrum of the extract showed hydroxyl (-OH), alkyl (C-H), ether (C-O) and ester (–C=O) absorption characteristic of teriterpenoid saponins. The C-O-C absorption indicated glycoside linkages to the sapogenins. The crude saponin extracted from sea cucumber was cytotoxic to A549 cells.Conclusion:
The 80% ethanol fraction of saponin isolated from H. leucospilota exhibited hemolytic activity and offers promise as an anti-cancer candidate.Key Words: Sea cucumber, Holothuria leucospilota, Saponin, Hemolytic assay, Cytotoxicity assay 相似文献127.
Amel?Soltani Hela?Louati Amel?Hanachi Fida?Ben Salem Naceur?Essid Patricia?Aissa Ezzeddine?MahmoudiEmail author Hamouda?Beyrem 《Biologia》2012,67(2):377-383
A microcosm experiment was used to examine the response of nematode in terms of density and diversity at different levels
of permethrin contamination. The sediments were contaminated with three permethrin concentrations [P1: low (5 mg kg−1), P2: medium (25 mg kg−1) and P3: high (250 mg kg−1)] and the effects were evaluated after 30 days. The results from univariate and multivariate analyses showed significant
differences between nematode assemblages from uncontaminated control and those from permethrin treatments. All univariate
indices changed significantly at all the levels of permethrin contamination. In fact, the total nematode abundance (I), Shannon-Weaner index (H′), species richness (d), evenness (J′) and number of species (S) decreased significantly in all the contaminated microcosms. In addition, the results from multivariate analyses of the species
abundance data demonstrated that permethrin affects the responses of nematode species. These significant modifications in
nematode community structures with response to permethrin contamination were the consequences of a different specific tolerance
to this pesticide. Thus, Araeolaimus bioculatus, Calomicrolaimus honestus, Oncholaimus campylocercoides and Theristus pertenuis characterized by increased abundances in all treated replicates, appeared to be “permethrin-resistant” species. Daptonema trabeculosum was eliminated in all the doses tested and seemed to be a very sensitive species to permethrin contamination. 相似文献
128.
129.
Fatemeh Vahid Dastjerdi Bahman Zeynali Azita Parvaneh Tafreshi Anahita Shahraz Mahin Sadat Chavoshi Irandokht Khaki Najafabadi Marzieh Mowlavi Vardanjani Amir Atashi Masoud Soleimani 《Cell biology international》2012,36(11):967-972
GSK‐3β is a key molecule in several signalling pathways, including the Wnt/β‐catenin signalling pathway. There is increasing evidence suggesting Wnt/β‐catenin signalling is involved in the neural differentiation of embryonic, somatic and neural stem cells. However, a large body of evidence indicates that this pathway maintains stem cells in a proliferative state. To address this controversy, we have investigated whether the Wnt/β‐catenin pathway is present and involved in the neural differentiation of newly introduced USSCs (unrestricted somatic stem cells). Our results indicate that the components of Wnt/β‐catenin signalling are present in undifferentiated USSCs. We also show that the treatment of neurally induced USSCs with BIO (6‐bromoindirubin‐3′‐oxime), a specific GSK‐3β inhibitor and Wnt activator, for 5 and 10 days results in increased expression of a general neuronal marker (β‐tubulin III). Moreover, the expression of pGSK‐3β and stabilized β‐catenin increased by BIO in neurally induced USSCs, indicates that the Wnt pathway is activated and functional in these cells. Thus, inhibition of GSK‐3β in USSCs enhances their neural differentiation, which suggests a positive role of the Wnt/β‐catenin signalling pathway towards neural fate. 相似文献
130.
Marzieh Ghollasi Khosro Khajeh Nasrin Mollania Shekufeh Zareian Hossein Naderi-Manesh 《Biologia》2008,63(6):1051-1056
An amylopullulanase (L14-APU) from an Iranian thermophilic bacterium was purified and the effect of acarbose, as a general inhibitor of α-amylases, on pullulan and starch hydrolysis catalyzed by L14-APU was investigated. The inhibition is a competitive type whereas inhibition constants for pullulan and starch are 99 μM
and 72 μM, respectively. Investigation of the reaction rate in a system contains competitive substrates and the inhibition
type of acarbose in presence of different substrates suggests that L14-APU possesses only one active site for two activities. The analysis of metal ions and other reagents effects has shown that
Ca2+, Mg2+, Mn2+ and Co2+ enhanced both activities of the enzyme while N-bromosuccinimide treatment leads to the complete inactivation of the enzyme.
The enzyme activity increased in the presence of low concentration of SDS as a surfactant. 相似文献