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81.
A novel cimetidine ion-selective electrode is prepared, characterized and used in pharmaceutical analysis. The electrode incorporates PVC-membrane with cimetidine–phospohotungstate ion pair complex. The electrode exhibits a Nernstian response for cimetidine in the concentration range 1.0×10−5–1.0×10−2 M with a slope of 58±1 mV per decade. The limit of detection is 5.0×10−6 M. The electrode displays a good selectivity for cimetidine with respect to a number of common foreign inorganic and organic species. It can be used in the pH range 3.0–5.5. The membrane sensor was successfully applied to the determination of cimetidine in its tablets as well as its recovery from a urine sample.  相似文献   
82.
In this study, we aimed to estimate the prevalence of growth failure and identify the risk factors for this health problem in infants under two years old in Tehran, Iran. Using a cluster sampling method, 2182 infants' health files were randomly selected from eight health centers in Tehran. Growth failure was defined as a decrease in a child's weight (minimum 50 grams) at each attendance compared to the previous evaluation. The prevalence rate was between 0.05% and 6.2% at the different measurements. The regression analysis revealed that the presence of diarrhea [odds ratio (OR): 4.01, 95% confidence interval (CI): (3.50, 4.60)], respiratory infections [OR: 4.95, 95% CI: (4.40, 5.57)] and urinary tract infections [OR: 6.35, 95%CI: (3.97, 10.18)], as well as discontinuation of breast-feeding [OR: 10.91, 95%CI: (7.82, 15.23)], teething [OR: 4.14, 95% CI: (3.61, 4.75)] and complementary feeding [OR: 9.58, 95% CI: (6.48, 14.18)] were the significant risk factors for growth failure. Generally, our study showed a high prevalence of growth failure in infants less than two years in Tehran. More efforts are needed for promoting the knowledge level of mothers and healthcare providers to control this health problem in Iran.  相似文献   
83.
In this study, we investigated the effects of some denaturants, such as urea and heat, on structure and function of rabbit polyclonal antibody and its Fab fragments. Thermal unfolding studies by circular dichroism of antibody and Fab fragments showed that in acidic pH, antibody has multi-transitions whereas Fab fragments have one transition curve; however in neutral pH, thermal unfolding of both had one transition. Effects of urea on the structure of antibody and Fab were studied through fluorescence spectroscopy. Despite exposure of protein to high concentration of denaturant, partial unfolding occurred in both antibody and Fab, but the denaturation of Fab was more considerable than that of antibody. Functional studies indicated that urea and heat causes a decrease in affinity in both antibody and Fab, but deactivation of Fab is more considerable in comparison with the antibody molecule. Turbidity study of antibody and Fab showed that aggregation of Fab occurred at lower temperatures than that of antibody. Our results indicate that Fab has higher sensitivity in comparison with antibody in the unfolding, deactivation, and aggregation processes. Therefore, our data proposes a stabilizing role for Fc.  相似文献   
84.
Myocarditis is a well-recognized component of Kawasaki disease, with left ventricular dysfunction occurring in more than half of patients during the acute phase. The purpose of this study was to evaluate myocardial function in patients with Kawasaki disease using pulsed tissue Doppler imaging (TDI). Twenty-five patients with the diagnosis of acute Kawasaki disease were enrolled in the study. All patients underwent echocardiographic studies at the time of diagnosis of the disease, in its acute phase, prior to treatment, and then 4 weeks later. For an aged-matched control group with fever and no cardiac disease, the same echocardiographic evaluations were performed. Peak velocities of systolic (Sa), early diastolic (Ea), and late diastolic (Aa) motion of the annulus were obtained at the lateral and septal sides in apical four-chamber view, and TDI-derived myocardial performance index (TDI-MPI) was also calculated. Peak Ea velocity of lateral mitral annulus was decreased significantly during the acute phase of illness (14 ± 4.40 vs. 17.67 ± 4.41; P = 0.028). In seven patients with carditis, changes in Ea-to-Aa ratio of septum (1.28 ± 0.278 vs. 1.78 ± 0.49; P = 0.018) and lateral mitral annulus (1.23 ± 0.496 vs. 2.11 ± 0.822; P = 0.014) were statistically significant but TDI-MPI showed no statistically significant changes. This study showed that peak mitral annular Ea velocities obtained by TDI were significantly altered in the acute phase of Kawasaki disease. TDI- MPI does not add an incremental benefit to other indexes of myocardial performance for comprehensive myocardial function in the acute phase of Kawasaki disease.  相似文献   
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Background: Several methods for the treatment of colon cancer have been introduced, but none of them are safe and effective. We planned to evaluate the inhibitory effect of protein extract of licorice root on HT-29 and CT26 cell lines proliferation and apoptosis. Methods: Protein extract of licorice root was prepared in phosphate-buffered solution, and SDS-PAGE was used to isolate its fractions. HT-29, CT-26, and HEK293 cell lines were treated with various concentrations of the fractions and full extract of licorice. Cytotoxicity of licorice at various concentrations was assessed using MTT assay. Flow cytometry analysis was applied to evaluate the apoptosis. Results: Our results demonstrated that the concentrations of 5 μg/mL from 25 to 33 kDa fraction and concentration of 8 μg/mL from 62 kDa fraction had a significant inhibitory effect on both cancerous cell lines (P < 0.05), with no significant effect on the noncancerous cell line. The concentrations of 50 and 100 μg/mL from full extracts significantly increased apoptosis in CT26 cells [35.52 ± 7.5 (P = 0.048*) and 47.72 ± 8 (P 0.026*), respectively], but not in HT29 and noncancerous cell lines. Conclusions: Protein compounds of licorice showed anticancer properties and were able to induce apoptosis in both human colon cancer and mouse colon carcinoma cell lines.  相似文献   
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Backgroundtreatment of breast cancer as one of the most common cancers in the world remains an important area of drug development based on nanoparticulate systems. Effective targeted therapy of affected cells based on ligand conjugate biocompatible polymeric nanoparticles is an attractive perspective in this context.ObjectiveIn this study, a novel double effect nanoparticle based on Chitosan-Raloxifene conjugate was prepared for adjuvant therapy (hormone and chemo therapy) and drug targeting to breast cancer cells via estrogen receptor (ER).MethodsChitosan-raloxifene conjugate was synthesized. Related nanoparticles containing doxorubicin (DOX) were prepared and characterized. Experimental design study was performed to determine the optimum levels of variables in the preparation of nanoparticle. Drug loading, release, nanoparticle stability, and the effect of nanoparticles on cell viability were evaluated. Further, inhibition tests were performed to demonstrate that the function of these novel nanoparticles is mediated via ER.ResultsChitosan-raloxifene conjugate was successfully synthesized. The prepared nanoparticles showed sizes within 25–35 nm, more than 95% drug loading, about 60% of drug release and desired stability after 24 h. XTT assay on MCF-7 cell line illustrated that these nanoparticles could inhibit the cellular growth up to 60%. The results from inhibition tests revealed that prepared nanoparticles can inhibit cell growth via ER blocking.ConclusionThis study introduced chitosan-raloxifene nanoparticles containing doxorubicin as a novel targeting agent for adjuvant therapy of breast cancer. Open in a separate windowGraphical abstractElectronic supplementary materialThe online version of this article (10.1007/s40199-020-00338-9) contains supplementary material, which is available to authorized users.  相似文献   
90.
Increased prevalence of HCV infection in some lymphoproliferative diseases has been recently reported. In the present study, the frequency of anti-HCV antibody (Ab) together with hepatitis B surface (HBs) antigen (Ag) and anti-HBs Ab were determined in 42, 45 and 23 patients with essential mixed cryoglobulinemia (EMC), multiple myeloma (MM) and B-cell chronic lymphocytic leukemia (B-CLL), respectively. Thirty hospitalized patients with chronic rheumatoid arthritis (RA) were also included as a control. Specific antibodies to HCV antigens were detected by enzyme linked immunosorbent assay (ELISA) and positive results were confirmed by a recombinant immunoblot assay (RIBA). Our results demonstrated anti-HCV positivity in 69%, 11% and 4.3% of the EMC, MM and B-CLL samples tested, respectively. None of the RA patients were found to be anti-HCV positive. No significant differences were observed between the patients groups regarding the frequency of HBs Ag and anti-HBs Ab. Considering the low incidence of HCV infection in the control group and the normal population, these results confirm and extend previous reports on the possible role of HCV infection in the etiology of EMC and further suggest involvement of this virus in a subset of MM.  相似文献   
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