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Mitochondrial DNA (mtDNA) from cell suspension cultures of two intergeneric somatic hybrids of Pennisetum americanum (pearl millet) + Saccharum officinarum (sugarcane) was examined by restriction endonuclease digestion and hybridization with sorghum mtDNA cosmids. The mtDNA of one somatic hybrid was indistinguishable from that of pearl millet, while the second exhibited a combination of parental mtDNAs, suggesting mitochondrial fusion. Several novel, possibly recombinant, mtDNA restriction fragments were detected in this hybrid, which may have resulted from intergenmic recombination.Florida Agriculture Experiment Station Journal Series No: 8090. 相似文献
3.
Zohreh Tabaeizadeh 《Biotechnology letters》1989,11(6):411-416
Summary A rapid procedure for introducing foreign genes inLotus
corniculatus based on the induction of hairy roots byAgrobacterium
rhizogenes was developed. Expression of chloramphenicol acetyltransferase and neomycin phosphotransferase II was revealed in transgenic plants. Southern blot hybridization was used to confirm the genetic transformation. The transgenic plants looked normal and did not show any morphological modification compared to the seed grown plants. 相似文献
4.
Summary Leaf disc transformation-regeneration technique was applied to the drought tolerant wild relative of cultivated tomato,Lycopersicon chilense, using a plasmid construct which contained the coding sequences of neomycin phosphotransferase (NPTII) and chloramphenicol acetyltransferase (CAT) genes. The two genotypes used, LA2747 and LA1930, showed a distinct difference in their aptitude to transformation; a higher success rate was obtained for the first genotype in every stage of the process. Shoots were formed on the regeneration medium containing 100 g/ml kanamycin through direct or indirect organogenesis. Root formation became only possible when the concentration of kanamycin was reduced to 50 g/ml. Expression of chloramphenicol acetyltransferase gene was observed in all of the kanamycin-screened plants after they matured; the activity of the gene was absent or low in some of the young plants. The presence of the CAT gene in transgenic plants was further confirmed by Southern blot analysis. Although transgenic plants grew to maturity, they did not produce fruit, owing to the self incompatibility ofL. chilense.
Abbreviations BAP
6-benzylaminopurine
- CAT
chloramphenicol acetyltransferase
- 2,4-D
2,4-dichlorophenoxyacetic acid
- IAA
indole-3-acetic acid
- LB
Luria Broth
- EDTA
ethylenediamine-tetraacetic acid 相似文献
5.
Nazemian Maryam Hojati Vida Zavareh Saeed Madanchi Hamid Hashemi-Moghaddam Hamid 《International journal of peptide research and therapeutics》2020,26(1):259-269
International Journal of Peptide Research and Therapeutics - Chemotherapy using drug delivery systems can target tumor cells selectively and do not affect normal cells. In this paper, a specific... 相似文献
6.
Hosseini Zohreh Habibi Najafi Mohammad Bagher Yavarmanesh Masoud Ataei-Pirkooh Angila 《International journal of peptide research and therapeutics》2020,26(2):911-919
International Journal of Peptide Research and Therapeutics - LL-37 is a 37 amino acid long cationic peptide belonging to the cathelicidin family of antimicrobial peptides. Limited investigations... 相似文献
7.
Ghamari Fatemeh Vaezi Golamhassan Khaksari Mehdi Hojati Vida 《International journal of peptide research and therapeutics》2020,26(4):2029-2038
International Journal of Peptide Research and Therapeutics - Fetal exposure to alcohol can cause a wide range of long-lasting physiological and behavioral effects, collectively referred to as fetal... 相似文献
8.
P. Rahnamay Moshtagh S. Hojati Emami Ali M. Sharifi 《Journal of physiology and biochemistry》2013,69(3):451-458
Stem cells with the ability to differentiate into insulin-producing cells (IPCs) are becoming the most promising therapy for diabetes mellitus and reduce the major limitations of availability and allogeneic rejection of beta cell transplantations. Mesenchymal stem cells (MSCs) are pluripotent stromal cells with the ability to proliferate and differentiate into a variety of cell types including endocrine cells of the pancreas. This study sought to inspect the in vitro differentiation of human adipose-derived tissue stem cells into IPCs which could provide an abundant source of cells for the purpose of diabetic cell therapy in addition to avoid immunological rejection. Adipose-derived MSCs were obtained from liposuction aspirates and induced to differentiate into insulin-secreting cells under a three-stage protocol based on a combination of low-glucose DMEM medium, β-mercaptoethanol, and nicotinamide for pre-induction and high-glucose DMEM, β-mercaptoethanol, nicotinamide, and exendin-4 for induction stages of differentiation. Differentiation was evaluated by the analysis of morphology, dithizone staining, RT-PCR, and immunocytochemistry. Morphological changes including typical islet-like cell clusters were observed by phase-contrast microscope at the end of differentiation protocol. Based on dithizone staining, differentiated cells were positive and undifferentiated cells were not stained. Furthermore, RT-PCR results confirmed the expression of insulin, PDX1, Ngn3, PAX4, and GLUT2 in differentiated cells. Moreover, insulin production by the IPCs was confirmed by immunocytochemistry analysis. It is concluded that adipose-derived MSCs could differentiate into insulin-producing cells in vitro. 相似文献
9.
Mitra Kheirabadi Zohreh Sharafian Hossein Naderi-Manesh Udo Heineman Ulrich Gohlke Saman Hosseinkhani 《Biochimica et Biophysica Acta - Proteins and Proteomics》2013,1834(12):2729-2735
Firefly bioluminescence reaction in the presence of Mg2 +, ATP and molecular oxygen is carried out by luciferase. The luciferase structure alterations or modifications of assay conditions determine the bioluminescence color of firefly luciferase. Among different beetle luciferases, Phrixothrix hirtus railroad worm emits either yellow or red bioluminescence color. Sequence alignment analysis shows that the red-emitter luciferase from Phrixothrix hirtus has an additional arginine residue at 353 that is absent in other firefly luciferases. It was reported that insertion of Arg in an important flexible loop350–359 showed changes in bioluminescence color from green to red and the optimum temperature activity was also increased. To explain the color tuning mechanism of firefly luciferase, the structure of native and a mutant (E354R/356R/H431Y) of Lampyris turkestanicus luciferase is determined at 2.7 Å and 2.2 Å resolutions, respectively. The comparison of structure of both types of Lampyris turkestanicus luciferases reveals that the conformation of this flexible loop is significantly changed by addition of two Arg in this region. Moreover, its surface accessibility is affected considerably and some ionic bonds are made by addition of two positive charge residues. Furthermore, we noticed that the hydrogen bonding pattern of His431 with the flexible loop is changed by replacing this residue with Tyr at this position. Juxtaposition of a flexible loop (residues 351–359) in firefly luciferase and corresponding ionic and hydrogen bonds are essential for color emission. 相似文献
10.
Zohreh Varasteh Ola ?berg Irina Velikyan Gunnar Lindeberg Jens S?rensen Mats Larhed Gunnar Antoni Mattias Sandstr?m Vladimir Tolmachev Anna Orlova 《PloS one》2013,8(12)
Expression of the gastrin-releasing peptide receptor (GRPR) in prostate cancer suggests that this receptor can be used as a potential molecular target to visualize and treat these tumors. We have previously investigated an antagonist analog of bombesin (D-Phe-Gln-Trp-Ala-Val-Gly-His-Sta-Leu-NH2, RM26) conjugated to 1,4,7-triazacyclononane-N,N'',N''''-triacetic acid (NOTA) via a diethylene glycol (PEG2) spacer (NOTA-P2-RM26) labeled with 68Ga and 111In. We found that this conjugate has favorable properties for in vivo imaging of GRPR-expression. The focus of this study was to develop a 18F-labelled PET agent to visualize GRPR. NOTA-P2-RM26 was labeled with 18F using aluminum-fluoride chelation. Stability, in vitro binding specificity and cellular processing tests were performed. The inhibition efficiency (IC50) of the [natF]AlF-NOTA-P2-RM26 was compared to that of the natGa-loaded peptide using 125I-Tyr4-BBN as the displacement radioligand. The pharmacokinetics and in vivo binding specificity of the compound were studied. NOTA-P2-RM26 was labeled with 18F within 1 h (60-65% decay corrected radiochemical yield, 55 GBq/µmol). The radiopeptide was stable in murine serum and showed high specific binding to PC-3 cells. [natF]AlF-NOTA-P2-RM26 showed a low nanomolar inhibition efficiency (IC50=4.4±0.8 nM). The internalization rate of the tracer was low. Less than 14% of the cell-bound radioactivity was internalized after 4 h. The biodistribution of [18F]AlF-NOTA-P2-RM26 demonstrated rapid blood clearance, low liver uptake and low kidney retention. The tumor uptake at 3 h p.i. was 5.5±0.7 %ID/g, and the tumor-to-blood, -muscle and -bone ratios were 87±42, 159±47, 38±16, respectively. The uptake in tumors, pancreas and other GRPR-expressing organs was significantly reduced when excess amount of non-labeled peptide was co-injected. The low uptake in bone suggests a high in vivo stability of the Al-F bond. High contrast PET image was obtained 3 h p.i. The initial biological results suggest that [18F]AlF-NOTA-P2-RM26 is a promising candidate for PET imaging of GRPR in vivo. 相似文献