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51.
Carvacrol (CV) is a phenolic monoterpenoid found in essential oils of oregano (Origanum vulgare), thyme (Thymus vulgaris), pepperwort (Lepidium flavum), wild bergamot (Citrus aurantium bergamia), and other plants. Carvacrol possesses a wide range of bioactivities putatively useful for clinical applications such antimicrobial, antioxidant, and anticancer activities. Carvacrol antimicrobial activity is higher than that of other volatile compounds present in essential oils due to the presence of the free hydroxyl group, hydrophobicity, and the phenol moiety. The present review illustrates the state‐of‐the‐art studies on the antimicrobial, antioxidant, and anticancer properties of CV. It is particularly effective against food‐borne pathogens, including Escherichia coli, Salmonella, and Bacillus cereus. Carvacrol has high antioxidant activity and has been successfully used, mainly associated with thymol, as dietary phytoadditive to improve animal antioxidant status. The anticancer properties of CV have been reported in preclinical models of breast, liver, and lung carcinomas, acting on proapoptotic processes. Besides the interesting properties of CV and the toxicological profile becoming definite, to date, human trials on CV are still lacking, and this largely impedes any conclusions of clinical relevance.  相似文献   
52.
Bacterial infections continue to be one of the major causes of morbidity and mortality. Although many methods for diagnosing and treating of infectious diseases currently exist, there is an urgent need for new and improved approaches for bacterial destruction. The present study focuses on the conjugation of gold nanorods (GNRs) with gentamicin via the Nanothink acid linker and its application in delivery of gentamicin to infection foci due to Staphylococcus aureus. The interaction between gentamicin and gold nanorods was confirmed by FT-IR spectroscopy. The high performance liquid chromatography (HPLC) and atomic absorption spectroscopy analyses showed that 2050 gentamicin molecules were attached to each gold nanorod. The minimal inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values of gentamicin–GNRs conjugate showed the enhancement of antibacterial effect of gentamicin. The biodistribution study demonstrated localization of the complex at the site of Staphylococcal infection with high sensitivity in mouse model.  相似文献   
53.

Background

Visceral leishmaniasis (VL) is one of the most important parasitic diseases endemic in northwestern and southern areas of Iran. The aim of the present study was to review the records of children hospitalized with VL in order to characterize the clinical features of children as well as laboratory finding in Children Medical Center Hospital, Tehran, Iran.

Methods

The medical records of all children with a final diagnosis of VL were reviewed from 2004 to 2011. Demographic, clinical information, laboratory finding and treatment were considered.

Results

A total number of 34 children with confirmed VL through 2004-2011 were included in the study. The most prevalent sign and symptoms were fever (97.1%), pallor and weakness (97.1%), appetite loss (61.8%), splenomegaly (97.1%) and hepatomegaly (88.2%). The most frequent laboratory abnormalities were hematological including anemia (97.1%), thrombocytopenia (91.2%) and leukopenia (67.6%). Direct agglutination test (DAT) was performed in 23 cases and all of them showed anti-Leishmania antibodies with titers of ≥ 1: 3200. In addition, 90% of patients had positive rK39 results. Identification of Leishmania in the aspirates of the bone marrow was found in 83.3% of patients.

Conclusion

Regional surveillance system in order to monitoring of leishmaniasis trends as well as detection of new emerging foci is recommended.  相似文献   
54.

Background

Health literacy and e-health literacy are important factors helping people shape awareness of health behaviours in different aspects, including sleep hygiene behaviours. Good sleep hygiene behaviours promote sleep quality and are beneficial to overall mental wellbeing.

Objective

We aimed to examine if sleep hygiene behaviours may mediate the association between health literacy/e-health literacy and mental wellbeing.

Methods

Adult Iranian subjects (n = 9775; mean [SD] age = 36.44 [11.97] years; 67.3% females) completed the Health Literacy Instrument for Adults, eHealth Literacy Scale, three items on sleep hygiene behaviour that have been used in prior research and the Short Warwick Edinburgh Mental Wellbeing Scale. Data were then subjected to structural equation modelling (SEM) including 500 bootstrapping resampling to examine whether sleep hygiene is a mediator in the relationship between health literacy/e-health literacy and mental wellbeing.

Findings

Both health literacy and e-health literacy were significantly associated with mental wellbeing (r = .63 for health literacy and .39 for e-health literacy; p < .001) and sleep hygiene behaviours (r = .58 for health literacy and .36 for e-health literacy; p < .001). Sleep hygiene behaviours were significantly associated with mental wellbeing (r = .42; p < .001). Moreover, SEM that incorporated bootstrapping approaches indicated that sleep hygiene behaviours were significant mediators in the association between health literacy/e-health literacy and mental wellbeing.

Conclusions

We conclude that health literacy and e-health literacy are associated with mental health wellbeing in the Iranian population. Additionally, the association could be mediated via sleep hygiene behaviours.

Patient or Public Contribution

The study was co-designed with healthcare providers from the vice-Chancellor's Office for Health Affairs of Qazvin University of Medical Sciences as equal partners. Moreover, the women's health volunteers were involved in the design of the study.  相似文献   
55.
Abstract: This study investigated the potential antinociceptive efficacy of a novel synthetic curcuminoid analogue, 2,6‐bis‐(4‐hydroxy‐3‐methoxybenzylidene)cyclohexanone (BHMC), using chemical‐ and thermal‐induced nociception test models in mice. BHMC (0.03, 0.1, 0.3 and 1.0 mg/kg) administered via intraperitoneal route (i.p.) produced significant dose‐related inhibition in the acetic acid‐induced abdominal constriction test in mice with an ID50 of 0.15 (0.13–0.18) mg/kg. It was also demonstrated that BHMC produced significant inhibition in both neurogenic (first phase) and inflammatory phases (second phase) of the formalin‐induced paw licking test with an ID50 of 0.35 (0.27–0.46) mg/kg and 0.07 (0.06–0.08) mg/kg, respectively. Similarly, BHMC also exerted significant increase in the response latency period in the hot‐plate test. Moreover, the antinociceptive effect of the BHMC in the formalin‐induced paw licking test and the hot‐plate test was antagonized by pre‐treatment with the non‐selective opioid receptor antagonist, naloxone. Together, these results indicate that the compound acts both centrally and peripherally. In addition, administration of BHMC exhibited significant inhibition of the neurogenic nociception induced by intraplantar injections of glutamate and capsaicin with ID50 of 0.66 (0.41–1.07) mg/kg and 0.42 (0.38–0.51) mg/kg, respectively. Finally, it was also shown that BHMC‐induced antinociception was devoid of toxic effects and its antinociceptive effect was associated with neither muscle relaxant nor sedative action. In conclusion, BHMC at all doses investigated did not cause any toxic and sedative effects and produced pronounced central and peripheral antinociceptive activities. The central antinociceptive activity of BHMC was possibly mediated through activation of the opioid system as well as inhibition of the glutamatergic system and TRPV1 receptors, while the peripheral antinociceptive activity was perhaps mediated through inhibition of various inflammatory mediators.  相似文献   
56.
Four‐week‐old mice, weighing about 25–35 g were divided into five groups (8 mice in each group): vehicle control, low‐ (0.5 g/kg), middle‐ (1 g/kg), high‐ (3 g/kg), and exceptionally high‐dose (5 g/kg). After first and second weeks of intraperitoneal exposure to AgNPs, biochemical, histopathological, and electron microscopic ultrastructural changes were investigated. No significant changes were observed in SGOT and ALP levels after first week of exposure, while the level of SGPT significantly increased (p < 0.05) in 2nd week treated mice, indicating that inflammatory of liver might be induced by high‐dose (3 and 5 g/kg) of AgNPs. No obvious changes were observed for UA and BUN in all groups of treated mice. However, significant (p < 0.05) decrease in CR level was noticed in all groups of treated mice only at high‐dose (3 and 5 g/kg). No remarkable changes in lipid profile were observed. Light microscopic histopathological investigation shows that first week treatment had not perceptible effect on the cytoarchitecture on liver, kidney, and spleen; while, second week treatment had only sporadic mild effects on these organs. However, no ultrastructural electron microscopic changes were observed in liver, kidney, and spleen of mice treated with 0.5, 1, and 3 g/kg of AgNPs when sacrificed on first and second week; while, exceptionally high‐dose (5 g/kg) of AgNPs resulted in slight nuclear chromatin condensation and irregularities in nuclear membrane. The results suggested that AgNPs could be well tolerated in mice when given intraperitoneally and no death has been found during the experiment in any groups of treated mice. Interestingly, significant (<0.05) decrease in glucose levels in all experiment group is suggestive of curious hypoglycemic role of AgNPs warranting further study to explore its possible therapeutic potential in hyperglycemic conditions as well as its mechanism of action at molecular level. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 945–956, 2016.  相似文献   
57.
Homology modeling in combination with molecular docking studies has been applied to predict the binding modes of the Hepatitis C virus (HCV) NS5B-3a inhibitors within the pocket of NS5B polymerase of HCV genotype 3a. Structure modeling and docking using Genetic Optimization for Ligand Docking (GOLD) were carried out to understand the ligand binding properties of NS5B-3a and to identify a potent inhibitor against it. The three-dimensional homology model of Pakistani strain is not available and was built based on the HCV-J4 NS5B polymerase structure. Compound 1 possessing high GOLD fitness score of 62.17 with IC50 value of 0.04 μM was selected as the potent inhibitor. The docking analysis depicted that hydrogen bonding, ionic and hydrophobic interactions contributed significantly for its ligand binding and the amino acid residues Arg442 and His403 seemed to be the anchor residues for receptor recognition. For developing a connection between the experimental bioactivities and GOLD fitness scores, a squared correlation coefficient was calculated and found as acceptable with the value of r 2 = 0.67. These findings may act as potent lead in designing effective NS5B-3a inhibitors.  相似文献   
58.
Abstract

In this study, we investigated the therapeutic efficacy of a combination of liposomal amphotericin B (Lip-Amp B) and Methylglyoxal (Lip-MG) against Candida albicans in the leukopoenic mice. The antifungal efficacy of Lip-Amp B or Lip-MG or a combination of Lip-Amp B and Lip-MG was evaluated by the analysis of the survival rate and the fungal load in the treated mice. The immune-stimulatory effect of Lip-MG on macrophages was evaluated by analysing the secretion of proinflammatory cytokines. C. albicans infected mice treated at the doses of 1 and 2?mg/kg of Lip-Amp B showed 20% and 50% survival rates, respectively. Whereas the mice treated with free Amp B at the same doses died within 40?days of treatment. Interestingly, C. albicans infected mice treated with a combination of Lip-Amp B and Lip-MG had 70% survival rate on day 40 postinfection. Moreover, treatment of macrophages with Lip-MG increased their fungicidal activity and the secretion of proinflammatory cytokines, including TNF-α and IL-1β. These findings suggested that co-treatment with Lip-Amp B and Lip-MG had a synergistic effect and could be effective against C. albicans in immunocompromised subjects.  相似文献   
59.
The present study aimed to investigate the applicability of Universal ThermalClimate Index (UTCI) as an innovative and science-based index in public health researches,in occupational heat stress assessment. All indoor and outdoor workers (200 people) ofBrick industries of Shahroud, Iran participated in the research. First, the environmentalvariables such as air temperature, wet-bulb temperature, globe temperature, air velocityand relative humidity were measured; then UTCI and WBGT (wet-bulb globe temperature)indices were calculated. Simultaneously, physiological parameters including systolic anddiastolic blood pressure, oral temperature, skin temperature, tympanic temperature andheart rate of workers were measured. UTCI and WBGT indices were 34.2 ± 2°C, 21.8 ± 1.8°Cin the outdoor environments and 38.1 ± 4.4°C, 24.7 ± 3.3°C at the indoor environments,respectively. There were the weak inverse relationships between UTCI and WBGT indices atthe outdoor environments and physiological responses such as systolic blood pressure, anddiastolic blood pressure. However, there were no similar results for indoor environments.The significant relationships were found between UTCI and WBGT at both indoor and outdoorenvironments. Both UTCI and WBGT indices are suitable for assessing the occupational heatstress. Although, UTCI index seems more appropriate for heat stress assessment in theenvironments with low humidity and air velocity.  相似文献   
60.
Langerhans cells (LC) are key mediators of contact allergenicity in the skin. However, no in vitro methods exist which are based on the activation process of LC to predict the sensitization potential of chemicals. In this study, we have evaluated the performances of MUTZ-3, a cytokine-dependent human monocytic cell line, in its response to sensitizers. First, we compared undifferentiated MUTZ-3 cells with several standard human cells such as THP-1, KG-1, HL-60, K-562, and U-937 in their response to the strong sensitizer DNCB and the irritant SDS by monitoring the expression levels of HLA-DR, CD54, and CD86 by flow cytometry. Only MUTZ-3 and THP-1 cells show a strong and specific response to sensitizer, while other cell lines showed very variable responses. Then, we tested MUTZ-3 cells against a wider panel of sensitizers and irritants on a broader spectrum of cell surface markers (HLA-DR, CD40, CD54, CD80, CD86, B7-H1, B7-H2, B7-DC). Of these markers, CD86 proved to be the most reliable since it detected all sensitizers, including benzocaine, a classical false negative in local lymph node assay (LLNA) but not irritants. We confirmed the MUTZ-3 response to DNCB by real-time PCR analysis. Taken together, our data suggest that undifferentiated MUTZ-3 cells may represent a valuable in vitro model for the screening of potential sensitizers.  相似文献   
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