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143.
Afshin Nikkhoo Narges Rostami Mohammad Hojjat-Farsangi Gholamreza Azizi Bahman Yousefi Ghasem Ghalamfarsa Farhad Jadidi-Niaragh 《Journal of cellular biochemistry》2019,120(6):9300-9314
Breast cancer is the most prevalent cancer in women. Despite improvements in treatment, the rate of breast cancer-related deaths is still high, and this issue needs further, accurate investigations. Although several treatment options are available, none of them are efficient for complete remission, particularly in advanced stages of the disease. It is known that cancerous cells have dysregulated apoptosis-related pathways, by which they can remain alive for a long time, expand freely, and escape from apoptosis-inducing drugs or antitumor immune responses. Therefore, modulation of apoptosis resistance in cancer cells may be an efficient strategy to overcome current problems faced in the development of immunotherapeutic approaches for the treatment of breast cancer. The inhibitors of apoptosis protein (IAPs) are important targets for cancer therapy because it has been shown that these molecules are overexpressed and highly active in various cancer cells and suppress apoptosis process in malignant cells by blockage of caspase proteins. There is evidence of Smac mimetics efficacy as a single agent; however, recent studies have indicated the efficacy of current anticancer immunotherapeutic approaches when combined with Smac mimetics, which are potent inhibitors of IAPs and synthesized mimicking Smac/Diablo molecules. In this review, we are going to discuss the efficacy of treatment of breast cancer by Smac mimetics alone or in combination with other therapeutics. 相似文献
144.
Raman and Raman optical activity (ROA) spectra were collected for four RNA oligonucleotides based on the EMCV IRES Domain I to assess the contributions of helix, GNRA tetraloop, U·C mismatch base pair and pyrimidine-rich bulge structures to each. Both Raman and ROA spectra show overall similarities for all oligonucleotides, reflecting the presence of the same base paired helical regions and GNRA tetraloop in each. Specific bands are sensitive to the effect of the mismatch and asymmetric bulge on the structure of the RNA. Raman band changes are observed that reflect the structural contexts of adenine residues, disruption of A-form helical structure, and incorporation of pyrimidine bases in non-helical regions. The ROA spectra are also sensitive to conformational mobility of ribose sugars, and verify a decrease in A-type helix content upon introduction of the pyrimidine-rich bulge. Several Raman and ROA bands also clearly show cooperative effects between the mismatch and pyrimidine-rich bulge motifs on the structure of the RNA. The complementary nature of Raman and ROA spectra provides detailed and highly sensitive information about the local environments of bases, and secondary and tertiary structures, and has the potential to yield spectral signatures for a wide range of RNA structural motifs. 相似文献
145.
Noghani Amirhessam Eskafi Asadpour Reza Saberivand Adel Mazaheri Zohreh Hamidian Gholamreza 《Molecular biology reports》2022,49(3):2197-2207
Molecular Biology Reports - The main purpose of this study was to investigate the effect of D-serine (DS) and Dizocilpine (MK-801) on the proliferation of spermatogonial stem cells (SSCs) in... 相似文献
146.
Bayram Hashemzadeh Esmaeil Idani Gholamreza Goudarzi Kambiz Ahmadi Ankali Mohammad Javad Zare Sakhvidi Ali Akbar Babaei Hassan Hashemzadeh Mehdi Vosoughi Mohammad Javad Mohammadi Abdolkazem Neisi 《Saudi Journal of Biological Sciences》2019,26(3):473-480
The aim of this study was to determine the correlation between PM2.5 and NO2 pollutants and oxidative stress marker (8-isoprostane) and lung function tests (FVC and FEV1) in healthy children who were living and studying in three different areas of Ahvaz city including A1: Naderi site with high traffic, A2: Alavi Alley site with average traffic, and A3: Ein 2 site with low traffic (a rural area on the suburb of Ahvaz). 30 students in the 12–13 year-old range were selected from each studied zone (1, 2 and 3 sites) during three months of year. Of each student, one sample was taken every two weeks to measure 8-isoprostane of exhaled breath condensate (EBC). Air pollution data were collected from three air quality monitoring stations. Also, the relationship between air pollution and 8-isoprostane as well as lung function tests were determined using generalized estimating equations (GEE). The mean concentration of PM2.5 and NO2 in A1, A2 and A3 areas were 116, 92 and 45 (μg/m3) also 77, 53 and 14 (ppb) respectively. Among all studied students, there was a significant correlation between the increase of mean concentration of PM2.5 and NO2 in 1–4 before sampling day, increased 8-isoprostane concentration and decreased FEV1, while there was no significant correlation between them and decreased FVC. In A1 site, an increase in IQR (13 μg/m3) PM2.5 and IQR (6.5 ppb) NO2 on 1–4 days before sampling was associated with 0.38 unit (95% CI: 0.11, 0.65) and 1.1 unit (95% CI: 0.85, 1.35) increase in 8-isoprostane concentration, also decreased 121 ml and 190 ml FEV1, respectively. Results showed that the short-term exposure to traffic-related air pollution can decrease the values of lung function indices and increase the oxidative stress. It may adversely affect children’s lungs. 相似文献
147.
Bahrami G Kiani A Mirzaeei S 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,832(2):197-201
A simple and ultra rapid high performance liquid chromatographic (HPLC) method coupled with alumina extraction and fluorescence detection was described for determination of methyldopa in human serum. The drug and an internal standard were adsorbed onto alumina and eluted using acidic methanol. The eluate was directly injected onto ODS reverse phase column using a mixture of phosphate buffer (0.05 M) containing triethylamine (100 microl/l, v/v; pH 2.3) and methanol (92:8, v/v) at a flow rate of 2.1 ml/min as the mobile phase. The fluorescence detector excitation and emission wavelengths were set at 270 and 320 nm, respectively. No interference in the assay from any endogenous substances or other concurrently used drugs was observed and the retention times of I.S. and the drug were 1.7 and 2.4 min, respectively with total run time (injection to injection) of less than 3.5 min. The limit of quantification was evaluated to be 2 ng/ml. Validity of the method was studied and the method was precise and accurate with a linearity range from 20 ng/ml to 5000 ng/ml. This method has been used in a randomized crossover bioequivalence study of two different methyldopa preparations in 24 healthy volunteers. 相似文献
148.
Bahrami G Mohammadi B 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2006,837(1-2):24-28
Most of the published methods for analysis of gabapentin, an antiepileptic agent, in human serum require automated o-phthalaldehyde derivatization of the drug and immediate injection of the unstable derivatives formed. A new, very sensitive and simple high-performance liquid chromatographic method for quantitation of the drug in human serum using 4-chloro-7-nitrobenzofurazan (NBD-Cl) as a fluorescent labeling agent is presented. In this method the sensitivity was significantly improved and the limit of quantification of 0.002 microg/ml was obtained using 100 microl serum sample and 10 microl injection. However, the LOQ can be improved by increasing the sampling volume. The procedure involved protein precipitation of serum by acetonitrile followed by derivatization with NBD-Cl. Amlodipine was used as internal standard and chromatographic separation was performed on a Shimpack CLC-C18 (150 mm x 4.6 mm) column. The fluorescence derivative of the drug was monitored at excitation and emission wavelengths of 470 and 537 nm, respectively. A mobile phase consisting of methanol and sodium phosphate buffer (0.05 M; pH 2.5) containing 1 ml/l triethylamine (65:35, v/v) was used. The calibration curve was linear over the concentration range of 0.002-15 microg/ml. No interferences were found from commonly co-administrated antiepileptic drugs. The method was applied in a randomized cross-over bioequivalence study of two different gabapentin preparations in 24 healthy volunteers. 相似文献
149.
Gholivand K Alizadehgan AM Mojahed F Dehghan G Mohammadirad A Abdollahi M 《Zeitschrift für Naturforschung. C, Journal of biosciences》2008,63(3-4):241-250
The differences in the inhibition activity of organophosphorus agents are a manifestation of different molecular properties of the inhibitors involved in the interaction with the active site of enzyme. We were interested in comparing the inhibition potency of four known synthesized carbacylamidophosphates with the general formula RC(O)NHP(O)Cl2, constituting organophosphorus compounds, where R = CCl3 (1), CHCl2 (2), CH2Cl (3) and CF3 (4), and four new ones with the general formula RC(O)NHP(O)(R')2, where R' = morpholine and R = CCl3 (5), CHCl2 (6), CH2Cl (7), CF3 (8), on AChE and BuChE activities. In addition, in vitro activities of all eight compounds on BuChE were determined. Besides, in vivo inhibition potency of compounds 2 and 6, which had the highest inhibition potency among the tested compounds, was studied. The data demonstrated that compound 2 from the compound series 1 to 4 and compound 6 from the compound series 5 to 8 are the most sensitive as AChE and BuChE inhibitors, respectively. Comparing the IC50 values of these compounds, it was clear that the inhibition potency of these compounds for AChE are 2- to 100-fold greater than for BuChE inhibition. Comparison of the kinetics (IC50, Ki, kp, KA and KD) of AChE and BuChE inactivation by these compounds resulted in no significant difference for the measured variables except for compounds 2 and 6, which appeared to be more sensitive to AChE and BuChE by significantly higher kp and Ki values and a lower IC50 value in comparison with the other compounds. The LD50 value of compounds 2 and 6, after oral administration, and the changes of erythrocyte AChE and plasma BuChE activities in albino mice were studied. The in vivo experiments, similar to the in vitro results, showed that compound 2 is a stronger AChE and BuChE inhibitor than the other synthesized carbacylamidophosphates. Furthermore, in this study, the importance of electropositivity of the phosphorus atom, steric hindrance and leaving group specificity were reinforced as important determinants of inhibition activity. 相似文献
150.
Longidorus kheirii n. sp., a parthenogenetic species, was found in soil samples collected from the rhizosphere of Rosa sp. growing in a natural mountainous region close to Maragheh city, northwestern Iran. It is characterised by having a long body (6.7-9 mm), a 19.5-23 mum wide head continuous with the body contour, a truncate and slightly concave lip region with convex sides between the anterior end and the guide-ring, an odontostyle 113-130 mum long, an odontophore 69-97.5 mum long, a body width of 90.5-117.5 mum at the mid-body, a long, wide oesophageal bulb (149.5-193.5 x 39.5-48 mum), a tail length of 47-72 mum, a male with 11 ventromedian supplements and spicules of 85 mum in length, and four juvenile stages. The ribosomal 18S rDNA gene of L. kheirii n. sp., L. leptocephalus Hooper, 1961, L. profundorum Hooper, 1966 L. euonymus Mali & Hooper, 1973 and two unidentified species listed as Longidorus sp. 1 and Longidorus sp. 2, all recovered from northwestern Iran in the same survey, and the ITS1 of L. kheirii n. sp. and Longidorus sp. 1 were sequenced in order to investigate the phylogenetic relationships with other previously sequenced Longidorus species. 相似文献