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41.
Manifestations of viral infections like human immune deficiency virus (HIV) differ between women and men. There are some reports due to a higher risk of thrombosis due to antiphospholipid syndrome in HIV-infected women compared with men. The purpose of this study was demonstrating the impact of gender on serum concentration of antiphospholipid and anticardiolipin antibodies in HIV-infected patients. A total of 58 HIV-infected patients and 58 age, sex-matched healthy adults were enrolled. We measured platelets count, hemoglobin, partial thromboplastin time (PTT); prothrombin time (PT), international normalized ratio (INR), antiphospholipid IgG/IgM and anticardiolipin IgG/IgM serotypes in our studied population. Age, male-to-female ratio, hemoglobin level, PT, INR, antiphospholipid IgM isotype, anticardiolipin IgM and IgG isotypes levels were not significantly different between HIV-infected patients and healthy individuals, when CD4+ T-cell count, CD8+ T-cell count, platelet count, and PTT were significantly lower, and antiphospholipid IgG isotype levels was significantly higher in HIV patients. Antiphospholipid IgG isotypes (3.2 [2.8–4.2] vs. 2.5 [2.3–3.1]; P?<?0.001) and anticardiolipin IgG isotypes (2.2 [1.9–2.7] vs. 1.4 [1.4–1.9]; P?<?0.001) were significantly higher in HIV-infected women than in HIV-infected men. Antiphospholipid IgG/IgM and anticardiolipin IgG/IgM were significantly correlated in HIV-infected men and women when they did not had any correlation in controls. We suggest that HIV infection accelerate thrombosis in women more profoundly than in men, as a result of differences in disease progression and response to therapy in these patients.  相似文献   
42.
The aim of this study was to assess peri-operative complications, safety and efficacy of non-cemented femoral fixation in total hip arthroplasty (THA) as compared to cemented femoral fixation in the elderly population. Fifty-two matched pair analysis of patients with 75 years of age and older (104 patients), who underwent primary THA from June 1997 to December 2004, was performed based on age, sex, BMI, and Charnley classification. Mean age was 81 years (75–101) and the average follow up was 3.1 ± 2.9 years (1.2–6.4). There was no difference in peri-operative cardiopulmonary complications, pulmonary failures, deep venous thrombosis, pulmonary embolus, length of stay, or discharge deposition between the two groups. Non-cemented fixation is safe and effective in patients older than 75 years of age.  相似文献   
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A series of sila‐organosulphur compounds containing 1,2,3‐triazole cores were screened for their cytotoxic activity on human breast cancer cell line MCF‐7. Most of the tested compounds exhibited moderate‐to‐good activity against the cancer cells. Especially, the compound 4‐((2‐(trimethylsilyl)ethynylthio)methyl)‐1‐benzyl‐1H‐1,2,3‐triazole ( 3a) from series of sila‐substituted thioalkyne 1,2,3‐triazoles (STATs) and the compounds 3‐(1‐benzyl‐1H‐1,2,3‐triazol‐4‐yl)‐1‐mercapto‐1,1‐bis(trimethylsilyl)propane‐2‐thione ( 4a) and 1‐mercapto‐1,1‐bis(trimethylsilyl)‐3‐(1‐phenethyl‐1H‐1,2,3‐triazol‐4‐yl)propane‐2‐thione ( 4e) from series of sila‐substituted mercapto‐thione 1,2,3‐triazoles (SMTTs) exhibited promising cytotoxicity against MCF‐7 with IC50 values of 35.17, 32.63 and 30.3 μg/mL, respectively. In addition, the possible mechanisms for inhibition of cell growth and induction of apoptotic cell death were explored by DAPI staining, cell cycle analysis and qRT‐PCR. The synthetic compounds were evaluated for their in vitro antibacterial activities, and as a result, the most prominent effects were observed for 3e and 4e . Especially, 3e was found to be quite active against all the tested strains with the MIC values ranging from 15 to 62 μg/mL, except P. aeruginosa. The results of the time‐kill assay suggested that the compound of 3e completely inhibited the growth of both gram‐negative bacteria, A. baumannii, and gram‐positive bacteria, S. aureus. In addition, SEM analysis confirmed morphostructural damage of the bacteria. Our findings could be applicable for developing dual‐targeting anticancer/antibacterial therapeutics.  相似文献   
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46.

Purpose

The aim of this research work was to explore the possibility of providing multifunctional oral insulin delivery system by conjugating several types of dipeptides on chitosan and trimethyl chitosan to be used as drug carriers.

Method

Conjugates of Glycyl-glycine and alanyl-alanine of chitosan and trimethyl chitosan (on primary alcohol group of polymer located on carbon 6) were synthesized and nanoparticles containing insulin were prepared for oral delivery. Preparation conditions of nanoparticles were optimized and their performance to enhance the permeability of insulin as well as cytotoxicity of nanoparticles in Caco-2 cell line was evaluated. To evaluate the efficacy of orally administered nanoparticles, nanoparticles with the most permeability enhancing ability were studied in male Wistar rats as animal model by measuring insulin and glucose Serum levels.

Result

Structural study of all the conjugates by infrared spectroscopy and nuclear magnetic resonance confirmed the successful formation of the conjugates with the desirable substitution degree. By optimizing preparation conditions, nanoparticles with expected size (157.3–197.7?nm), Zeta potential (24.35–34.37?mV), polydispersity index (0.365–0.512), entrapment efficiency (70.60–86.52%) and loading capacity (30.92–56.81%), proper morphology and desirable release pattern were obtained. Glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan showed 2.5–3.3 folds more effective insulin permeability in Caco-2 cell line than their chitosan counterparts. In animal model, oral administration of glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan demonstrated reasonable increase in Serum insulin level with relative bioavailability of 17.19% and 15.46% for glycyl-glycine and alanyl-alanine conjugate nanoparticles, respectively, and reduction in Serum glucose level compared with trimethyl chitosan nanoparticles (p?<?0.05).

Conclusion

It seems that glycyl-glycine and alanyl-alanine conjugate nanoparticles of trimethyl chitosan have met the aim of this research work and have been able to orally deliver insulin with more than one mechanism in animal model. Hence, they are promising candidates for further research studies.  相似文献   
47.
Nanoscaled quantum dots (QDs), with unique optical properties have been used for the development of theranostics. Here, InP/ZnS QDs were synthesised and functionalised with folate (QD-FA), D-glucosamine (QD-GA) or both (QD-FA-GA). The bi-functionalised QDs were further conjugated with doxorubicin (QD-FA-GA-DOX). Optimum Indium to fatty acid (In:MA) ratio was 1:3.5. Transmission electron microscopy (TEM) micrographs revealed spherical morphology for the QDs (11?nm). Energy-dispersive spectroscopy (EDS) spectrum confirmed the chemical composition of the QDs. MTT analysis in the OVCAR-3 cells treated with bare QDs, QD-FA, QD-GA, QD-FA-GA and QD-FA-GA-DOX (0.2?mg/mL of QDs) after 24?h indicated low toxicity for the bare QDs and functionalised QDs (about 80–90% cell viability). QD-FA-GA-DOX nanoparticles elicited toxicity in the cells. Cellular uptake of the engineered QDs were investigated in both folate receptor (FR)-positive OVCAR-3 cells and FR-negative A549 cells using fluorescence microscopy and FACS flow cytometry. The FA-functionalised QDs showed significantly higher uptake in the FR-positive OVCAR-3 cells, nonetheless the GA-functionalised QDs resulted in an indiscriminate uptake in both cell lines. In conclusion, our findings indicated that DOX-conjugated FA-armed QDs can be used as theranostics for simultaneous imaging and therapy of cancer.  相似文献   
48.
Anxiety disorders are among the most common mental disorders. Drugs that are often administered to manage medical problems cause rebound anxiety. The use of morphine and tramadol has increased in recent decades. In the present study, the effects of morphine and tramadol exposure during the neonatal and prepubertal periods on anxiety‐like behaviours in prepubertal rats were investigated. Male neonate rats were injected subcutaneously with saline, morphine or tramadol (3–21 mg/kg) on a daily basis from postnatal Day (P) 8 to P14. On P22, rats were divided into seven groups (saline/saline, saline/tramadol, saline/morphine, tramadol/saline, tramadol/tramadol, morphine/saline and morphine/morphine) and were injected with saline, tramadol or morphine for seven consecutive days. All rats were tested in an elevated plus maze (EPM) on P24 (acute effects), P27 (chronic effects) and P29. Locomotor activity was increased by the second and third exposure to the EPM. Re‐exposure to chronic morphine and tramadol resulted in increased locomotor activity, whereas acute and chronic administration of these drugs induced no notable difference. Anxiety decreased markedly after re‐exposure to tramadol and this anxiolytic‐like behaviour was more dominant in EPM re‐exposure in rats that had received higher doses of tramadol. Re‐exposure to tramadol elicited a stronger anxiolytic‐like behaviour than re‐exposure to morphine. It can be concluded that repeated morphine and tramadol administration during the neonatal period followed by re‐exposure to these drugs at an immature stage produces considerable anxiolytic‐like behaviour. Exposure to chronic morphine and tramadol during the neonatal period may affect the developing brain, which may induce long‐term changes in the opioid response.  相似文献   
49.
Background and aim

Both short sleep duration and intake of sugar or sugar-sweetened beverages (SSBs) are associated with weight gain; but the linkage between sleep characteristics and sugar or SSBs intake was less studied. We aimed to evaluate the associations of sleep duration and sleep quality with sugar and SSBs intake among Iranian adults.

Method

This cross-sectional study consisted of 395 adults chosen among students of Isfahan University of Medical Sciences, based on a multistage cluster random sampling method. Sleep characteristics and dietary intakes and were assessed using the Pittsburgh Sleep Quality Index (PSQI) and a 147-item validated food frequency questionnaire, respectively.

Results

Mean age and percentage of women in the study population were 22.79 (year) and 51.8%, respectively. No significant difference was observed between sleep duration and sugar intake, but short sleepers (< 6 h/d) had higher consumption of SSBs intake (86.54 vs. 65.73 g/day; P = 0.05) in comparison with those who had more than 8 h/d of sleep. Poor quality sleepers had significantly higher intake of SSBs compared with those with good quality of sleeping (87.09 vs. 56.73 g/day; P = 0.004). No significant correlation was found between sleep duration and SSBs intake. However, sleep quality score was positively correlated with SSBs intake (rp:0.14, P = 0.007) in whole population, such that higher quality score (defined as poor sleep quality) was correlated with greater consumption of SSBs. Similar results were found in younger individuals (rp:0.27, P = 0.002) and non-obese participants (rp:0.14, P = 0.006).

Conclusion

We found that sleep duration was not associated with sugar or SSBs intake in Iranian adults. Poor sleep quality was correlated with high consumption of SSBs, especially in younger and non-obese individuals. More prospective investigations are required to confirm these findings.

  相似文献   
50.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - Chitosan (CS), as a natural polymer, has received a great deal of attention as a carrier for delivery of...  相似文献   
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