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551.
Ali Taheri Subramanian Jayasankar John A. Cline Manish N. Raizada Peter K. Pauls 《In vitro cellular & developmental biology. Plant》2012,48(1):23-29
We have cloned a WD-repeat gene from peach. The cloned gene is more than 3 kb and contains signature domains characteristic
of WD-repeat genes. Because of its high homology with AtTTG1, we hypothesized that this gene could be a TTG1 ortholog in peach.
Functional studies were carried out by complementing the trichome minus Arabidopsis ttg1-1 mutant with the putative peach TTG1 homolog. Successful restoration of normal trichomes was achieved in the resulting transgenics.
We further tested the possibility that this gene was the candidate gene differentiating peach and nectarine. Sequence analysis
indicated no difference in the full-length TTG1 and 1,600 bp of its promoter between peach and nectarine. 相似文献
552.
Preparation of an intelligent drug delivery system which releases the drug in response to the environmental stimuli in a controlled manner is one of the interesting subjects and it is the purpose of this study. Films composed of Eudragit RS and different percentages of plasticizers (0%, 5%, 10%, or 20% w/w based on polymer weight), poly ethylene glycol 400 or triethyl citrate (TEC), were prepared by solvent casting method. Glass transition temperatures of the films were determined by differential scanning colorimetery. Water uptake and drug permeation through membranes with the glass transition temperature (Tg) close to the body temperature were investigated. Propranolol hydrochloride and acetaminophen were used as model drugs in permeation studies. The results showed that Eudragit RS films with 20% of either plasticizer showed thermo-responsivity around body temperature. The water uptake of the films and the permeation rates of both drugs increased at temperatures above the Tg of the films. The films containing TEC was found to be more appropriate thermo-responsive membrane due to a higher sensitivity to temperature and more ability to control drug release. 相似文献
553.
Gholam Abbas Kasaei Hooriye Yahyaei Seiedeh Negar Mousavi Elham Pourdavoodi 《Molecular simulation》2013,39(12):1022-1031
2-Methoxytetrahydropyran (1), -thiopyran (2) and -selenopyran (3) have been chosen as model compounds to investigate the origin of the anomeric effect (AE). The impacts of the hyperconjugation, electrostatic and steric interactions on the conformational preferences of compounds 1–3 have been analysed by means of complete basis set-4, hybrid-density functional theory (B3LYP/6-311+G**) based methods and natural bond orbital (NBO) interpretation. Both levels of theory showed that the axial conformations of compounds 1–3 are more stable than their equatorial conformations. The Gibbs free energy difference (G eq–G ax) values (i.e. ΔG eq–ax) between the axial and equatorial conformations increase from compound 1 to compound 2 but decrease from compound 2 to compound 3. Based on the NBO results obtained, the AE associated with the electron delocalisation [i.e. Σ(endo-AEeq + exo-AEeq) ? Σ(endo-AEax + exo-AEax)] increase slightly from compound 1 to compound 2 but decrease from compound 2 to compound 3. Similar trend is also observed for the differences between the calculated total steric exchange energy values [i.e. Δ(TSEE)eq–ax]. On the other hand, the calculated differences between the dipole moment values of the axial and equatorial conformations [i.e. Δ(μeq–μax)] decrease from compound 1 to compound 3. These findings led to the proposal that the AE associated with the electron delocalisation (the hyperconjugation effect) is more significant for the explanation of the conformational preferences of compounds 1–3 than the electrostatic model. The correlations between the AE associated with the electron delocalisation, bond orders, TSEE, ΔG eq–ax, dipole–dipole interactions, structural parameters and conformational behaviours of compounds 1–3 have been investigated. 相似文献
554.
Fatemeh Saadabadi Masoud Mohajery Elham Poostchi Seyyed Ali Akbar Shamsian 《Reports of Biochemistry & Molecular Biology》2013,1(2):69-73
Background:
Leishmaniasis, especially cutaneous leishmaniasis, is considered an important health problem in many parts of Iran including Kharve, Khorasan Razavi province. Cutaneous leishmaniasis is caused by various species of Leishmania, each having a different secondary host. Thus, identifying the parasites’ specie is of paramount importance for containment strategy planning. The morphological differentiation of Leishmania species is not possible, rendering the molecular methods as the sole means to this purpose. Therefore, to identify the causative agent of cutaneous leishmaniasis in Kharve, Random Amplified Polymorphic DNA-PCR (RAPD-PCR) was used.Methods:
The disease was first confirmed by direct smears. Samples were gathered from 22 patients with established cutaneous leishmaniasis. The samples were immediately cultured in NNN medium, followed by sub-culture in RPMI-1640. Afterwards, DNA was extracted and amplified using RAPD-PCR. Electrophoresis patterns from each isolate were compared with reference strains of Leishmania major (L. major) and Leishmania tropica (L. tropica).Results:
The results of this study indicated that the parasite causing cutaneous leishmaniasis in Kharve is L. tropica.Conclusion:
It seems that L. tropica is the only causative agent of cutaneous leishmaniasis in Kharve, and RAPD-PCR is a suitable tool for Leishmania characterization in epidemiological studies.Key Words: Leishmania major, Leishmania tropica, RAPD-PCR, Khorasan, Kharve 相似文献555.
Ali Asghar Mohammadi Salman Taheri Sanaz Shisheboran Reza Ahdenov Maryam Mohammadi-Khanaposhtani Pedram Salehi Darjani Patrick Honarchian Masihi Aidin Shakiba Bagher Larijani Mohammad Mahdavi Nematollah Ahangar 《Journal of biochemical and molecular toxicology》2023,37(1):e23234
A new series of spiro[indene-1,2′-quinazolin]-4′(3′H)-one derivatives 4a–m were synthesized via a one-pot method and evaluated for anticonvulsant activities using pentylenetetrazole (PTZ) and maximal electroshock (MES)-induced seizures. Obtained results demonstrated that these compounds have not anticonvulsant activity in PTZ test while are active in the MES test. Among the synthesized compounds, the best anticonvulsant activity was obtained with compound 4h . This compound also was not neurotoxic. Given that the title new compounds have the pharmacophore requirement for benzodiazepine (BZD) receptor agonist, the most potent compound was assayed in vivo and in silico as BZD receptor agonist. After treatment with flumazenil as a standard BZD receptor antagonist, anticonvulsant activity of compound 4h decreased. Therefore, the involvement of BZD receptors in anticonvulsant activity of this compound confirmed. Furthermore, docking study of compound 4h in the BZD-binding site of GABAA receptor confirmed that this compound interacted with the important residues. 相似文献
556.
Delaram Jarchi Reza Boostani Mohammad Taheri Saeid Sanei 《Biomedical signal processing and control》2009,4(2):108-117
Localization of seizure sources prior to neurosurgery is crucial. In this paper, a new method is proposed to localize the seizure sources from multi-channel electroencephalogram (EEG) signals. Blind source separation based on second order blind identification (SOBI) is primarily applied to estimate the brain source signals in each window of the EEG signals. A new clustering method based on rival penalized competitive learning (RPCL) is then developed to cluster the rows of the estimated unmixing matrices in all the windows. The algorithm also includes pre and post-processing stages. By multiplying each cluster center to the EEG signals, the brain signal sources are approximated. According to a complexity value measure, the main seizure source signal is separated from the others. This signal is projected back to the electrodes’ space and is subjected to the dipole source localization using a single dipole model. The simulation results verify the accuracy of the system. In addition, correct localization of the seizure source is consistent with the clinical tests derived using the simultaneous intracranial recordings. 相似文献
557.
Elham Khodaverdi Farnaz Sadat Mirzazadeh Tekie Farzin Hadizadeh Haydar Esmaeel Seyed Ahmad Mohajeri Sayyed A. Sajadi Tabassi Gholamhossein Zohuri 《AAPS PharmSciTech》2014,15(1):177-188
Although conventional pharmaceuticals have many drug dosage forms on the market, the development of new therapeutic molecules and the low efficacy of instant release formulations for the treatment of some chronic diseases and specific conditions encourage scientists to invent different delivery systems. To this purpose, a supramolecular hydrogel consisting of the tri-block copolymer PLGA-PEG-PLGA and α-cyclodextrin was fabricated for the first time and characterised in terms of rheological, morphological, and structural properties. Naltrexone hydrochloride and vitamin B12 were loaded, and their release profiles were determined. 相似文献
558.
Kouhpayeh HR Hashemi M Hashemi SA Moazeni-Roodi A Naderi M Sharifi-Mood B Taheri M Mohammadi M Ghavami S 《Genetics and molecular research : GMR》2012,11(2):1075-1081
The protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene, which encodes an intracellular lymphoid-specific phosphatase, is considered an important regulator of T-cell activation. We investigated a possible association between the PTPN22 C1858T (R620W) polymorphism and pulmonary tuberculosis in an Iranian population. Single nucleotide polymorphisms of PTPN22 C1858T (rs2476601) were genotyped in 172 pulmonary tuberculosis cases and 204 normal subjects from Zaheden, Iran. Frequencies of genotypes CC, CT and TT of the PTPN22 C1858T polymorphism were 98.3, 1.7 and 0% in the pulmonary tuberculosis patients, and 96.1, 3.9 and 0% in the control group, respectively (P = 0.239). The frequency of the minor (T) allele was 0.8% in pulmonary tuberculosis patients and 2.0% in controls. Significant differences were not observed in genotype or allele frequencies of PTPN22 C1858T in the comparison between pulmonary tuberculosis patients and healthy subjects in our Iranian population sample. 相似文献
559.
Bénédicte Demeulder Elham Zarrinpashneh Audrey Ginion Benoit Viollet Louis Hue Mark H. Rider Jean-Louis Vanoverschelde Christophe Beauloye Sandrine Horman Luc Bertrand 《生物化学与生物物理学报:疾病的分子基础》2013,1832(6):780-790
Eukaryotic elongation factor 2 (eEF-2) and mammalian target of rapamycin (mTOR)–p70 ribosomal protein S6 kinase (p70S6K) signaling pathways control protein synthesis and are inhibited during myocardial ischemia. Intracellular acidosis and AMP-activated protein kinase (AMPK) activation, both occurring during ischemia, have been proposed to participate in this inhibition. We evaluated the contribution of AMPKα2, the main cardiac AMPK catalytic subunit isoform, in eEF2 and mTOR–p70S6K regulation using AMPKα2 KO mice. Hearts were perfused ex vivo with or without insulin, and then submitted or not to ischemia. Insulin pre-incubation was necessary to activate mTOR–p70S6K and evaluate their subsequent inhibition by ischemia. Ischemia decreased insulin-induced mTOR–p70S6K phosphorylation in WT and AMPKα2 KO mice to a similar extent. This AMPKα2-independent p70S6K inhibition correlated well with the inhibition of PKB/Akt, located upstream of mTOR–p70S6K and can be mimicked in cardiomyocytes by decreasing pH. By contrast, ischemia-induced inhibitory phosphorylation of eEF-2 was drastically reduced in AMPKα2 KO mice. Interestingly, AMPKα2 also played a role under normoxia. Its deletion increased the insulin-induced p70S6K stimulation. This p70S6K over-stimulation was associated with a decrease in inhibitory phosphorylation of Raptor, an mTOR partner identified as an AMPK target. In conclusion, AMPKα2 controls cardiac p70S6K under normoxia and regulates eEF-2 but not the mTOR–p70S6K pathway during ischemia. This challenges the accepted notion that mTOR–p70S6K is inhibited by myocardial ischemia mainly via an AMPK-dependent mechanism. 相似文献
560.
Elham Yazdani Roya Khosravi Jalil Hajizadeh Mohammad Ghadamyari 《Archives Of Phytopathology And Plant Protection》2013,46(3):328-339
The effect of essential oil of Satureja hortensis L. on food consumption, biochemical compounds and digestive and detoxification enzymes activity of lesser mulberry pyralid, Glyphodes pyloalis Walker was investigated. The percentage of feeding inhibition was dose dependent. The S. hortensis essential oil exhibited a significant antifeedant activity at the highest concentration used. The feeding indices such as efficiency of conversion of ingested food (ECI), efficiency of conversion of digested food (ECD), relative growth rate (RGR) and relative consumption rate (RCR) were decreased compared with the control in fifth instar larvae, while approximate digestibility (AD) index increased significantly. Results showed significant decreases in the amount of protein, lipid, carbohydrates and the activity level of α-amylase enzyme in treated larvae with S. hortensis essential oil. The activity level of detoxifying enzymes such as esterase and glutathione S-transferase were significantly affected by S. hortensis essential oil. The results of this study show high deterrence and antifeedant activity of this essential oil which deserves consideration in integrated pest management program. 相似文献