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961.
Influenza virosome is one of the commercially available vaccines that have been used for a number of years. Like other influenza vaccines, the efficacy of the virosomal vaccine is significantly compromised when circulating viruses do not have a good match with vaccine strains due to antigenic drift or less frequent emergence of a pandemic virus. A major advantage of virosome over other influenza vaccine platforms is its intrinsic adjuvant activity and potential carrier capability which have been exploited in this study to broaden vaccine protectivity by incorporating a conserved component of influenza virus in seasonal vaccine formulation. Influenza nucleoprotein (NP)-encoding plasmid was adsorbed onto surface of influenza virosomes as a virosome/DNA vaccine complex. Mice were immunized with a single dose of the influenza virosome attached with the NP plasmid or NP plasmid alone where both influenza virosomes and NP gene were derived from influenza A virus H1N1 New/Caledonia strain. Analysis of the cellular immune responses showed that 5μg (10-fold reduced dose) of the NP plasmid attached to the virosomes induced T cell responses equivalent to those elicited by 50μg of NP plasmid alone as assessed by IFN-γ and granzyme B ELISPOT. Furthermore, the influenza virosome/NP plasmid complex protected mice against intra-subtypic challenge with the mouse adapted H1N1 PR8 virus, while mice immunized with the virosome alone did not survive. Results of hemagglutination inhibition test showed that the observed intra-subtypic cross-protection could not be attributed to neutralizing antibodies. These findings suggest that influenza virosomes could be equipped with an NP-encoding plasmid in a dose-sparing fashion to elicit anti-influenza cytotoxic immune responses and broaden the vaccine coverage against antigenic drift.  相似文献   
962.
963.
Amikacin as an aminoglycoside antibiotic was chosen to be loaded in a cholesterol carrier with nanoparticle size and sustained release profile to increase the dose interval of amikacin and reduce side-effects. To support the stability of solid lipid nanoparticles (SLNs), freeze-drying was suggested. Factors affecting the freeze-drying process in the present study included the type and concentration of cryoprotectants. Pre-freezing temperature effects were also studied on particle size of SLNs of amikacin. In some preliminary experiments, important factors which influenced the particle size of SLNs after lyophilization were selected and a D-optimal design was applied to optimize the freeze-drying conditions in the production of SLNs with minimum particle size growth after freeze-drying. Zeta potential, DSC thermograms, release profiles and morphology of the optimized particles were studied before and after freeze-drying. Results showed sucrose changed the particle size of SLNs of amikacin from 149 ± 4 nm to 23.9 ± 16.7 nm; in that situation, the absolute value of zeta potential changed from 1 ± 0.7 mV to 13 ± 4 mV. The release profiles showed a sustained release behavior of the loaded drug that did not change significantly before and after freeze-drying, but a burst effect was seen after it in the first 2 h. DSC analysis showed chemical interaction between amikacin and cholesterol.  相似文献   
964.
Abstract

In the present study, alive attenuated Salmonella typhi Ty21a was introduced as a vehicle for smart delivery of gold nanoparticles to the tumours’ hypoxic regions. At the first step, the uptakes of gold nanoparticles with seven different decorations by S. typhi Ty21a was investigated using flow cytometry and inductively coupled plasma optical emission spectroscopy. The analyses demonstrated that folic acid functionalised gold nanoparticles (FA-GNPs) are the best candidates for producing the Golden Bacteria (GB). Subsequently, the GB and FA-GNPs efficacies for tumour targeting were investigated after intravenous injection to CT-26 tumour-bearing mice. The GB exhibited more GNPs delivery to the tumour in comparison with FA-GNPs. Moreover, GB injection causes more delivery of GNPs to the tumours’ central regions in comparison with tumours’ periphery. This trend is completely in reverse for FA-GNPs injected group. The ratios of peripheral to central regions’ gold concentration of the tumours were 1.95?±?0.13 and 0.61?±?0.10 for FA-GNPs and GB groups, respectively. This observation demonstrates higher accumulation of gold nanoparticles in the centre of the tumour due to their active delivery by the S. typhi Ty21a to the deeps of tumours.  相似文献   
965.

Background

The aim of this study was to identify, quantify, and compare the phytochemical contents, antioxidant capacities, and antibacterial activities of Aloe vera lyophilized leaf gel (LGE) and 95% ethanol leaf gel extracts (ELGE) using GC-MS and spectrophotometric methods.

Results

Analytically, 95% ethanol is less effective than ethyl acetate/diethyl ether or hexane (in the case of fatty acids) extractions in separating phytochemicals for characterization purposes. However, although fewer compounds are extracted in the ELGE, they are approximately 345 times more concentrated as compared to the LGE, hence justifying ELGE use in biological efficacy studies in vivo. Individual phytochemicals identified included various phenolic acids/polyphenols, phytosterols, fatty acids, indoles, alkanes, pyrimidines, alkaloids, organic acids, aldehydes, dicarboxylic acids, ketones, and alcohols. Due to the presence of the antioxidant polyphenols, indoles, and alkaloids, the A. vera leaf gel shows antioxidant capacity as confirmed by ORAC and FRAP analyses. Both analytical methods used show the non-flavonoid polyphenols to contribute to the majority of the total polyphenol content. Three different solvents such as aqueous, ethanol, and acetone were used to extract the bioactive compounds from the leaves of A. vera to screen the antibacterial activity selected human clinical pathogens by agar diffusion method. The maximum antibacterial activities were observed in acetone extracts (12 ± 0.45, 20 ± 0.35, 20 ± 0.57, and 15 ± 0.38 nm) other than aqueous and ethanol extracts.

Conclusion

Due to its phytochemical composition, A. vera leaf gel may show promise in alleviating symptoms associated with/or prevention of cardiovascular diseases, cancer, neurodegeneration, and diabetes.
  相似文献   
966.
One commonly used cement type for thermal applications is CAC containing 38–40% alumina, although the postheated behavior of this cement subjected to elevated temperature has not been studied yet. Here, through extensive experimentation, the postheated mineralogical and physicochemical features of calcium aluminate cement concrete (CACC) were examined via DTA/TGA, X-ray diffraction (XRD), and scanning electron microscopy (SEM) imaging and the variation in the concrete physical features and the compressive strength deterioration with temperature rise were examined through ultrasonic pulse velocity (UPV) values. In addition, other mechanical features that were addressed were the residual tensile strength and elastic modulus. According to the XRD test results, with the temperature rise, the dehydration of the C3AH6 structure occurred, which, in turn, led to the crystallization of the monocalcium dialuminate (CA2) and alumina (Al2O3) structures. The SEM images indicated specific variations in morphology that corresponded to concrete deterioration due to heat.  相似文献   
967.
OBJECTIVE: To summarize comprehensive informa- tion concerning ethnomedicinal uses, phytochem- istry, and pharmacological activities of parsley. METHODS: Databases including PubMed, Scopus, Google Scholar, and Web of Science were searched for studies focusing on the ethnomedicinal use, phytochemical compounds and biological and pharmacological activities of parsley. Data were col- lected from 1966 to 2013. The search terms were: "Parsley" or "Petroselinum crispum" or "Petroseli-num hortence". RESULTS: Parsley has been used as carminative, gastro tonic, diuretic, antiseptic of urinary tract, an- ti-urolithiasis, anti-dote and anti-inflammatory and for the treatment of amenorrhea, dysmenorrhea, gastrointestinal disorder, hypertension, cardiac dis- ease, urinary disease, otitis, sniffle, diabetes and al- so various dermal disease in traditional and folklore medicines. Phenolic compounds and flavonoids particularly apigenin, apiin and 6-Acetylapiin, es- sential oil mainly myristicin and apiol, and also cou- marins are the active compounds identified in Petroselinum crispum. Wide range of pharmacolog- ical activity including antioxidant, hepatoprotec- tive, brain protective, anti-diabetic, analgesic, spas- molytic, immunosuppressant, anti-platelet, gastro- protective, cytoprotective, laxative, estrogenic, di- uretic, hypotensive, antibacterial and antifungal ac- tivities have been exhibited for this plant in mod- ern medicine. CONCLUSION: It is expectant that this study result- ed in improvement the tendencies toward Petrose- linum crispum as a useful and important medicinal plant with wide range of proven medicinal activity.  相似文献   
968.

Objective

This investigation aims to evaluate the validity of a Persian Tanner Stages Self-Assessment Questionnaire.

Methods

In this cross sectional study, 190 male students aged 8-16 years selected from three layers of different regions of Tehran (North, Central and South) were enrolled. A Persian questionnaire illustrated with Tanner stages of puberty (genital development and pubic hair distribution) was prepared. Children were asked to select the illustration that best described their pubertal development. Tanner status of the children was also estimated by an independent physician using physical examination. The degree of agreement between subjects’ judgments with assessments made by the rater was compared through the calculation of the weighted kappa statistic coefficient.

Findings

We found a substantial agreement between self-assessment of pubertal development made by the children and doctor''s assessment of genital development (kappa=0.63, P<0.0001) and also the pubic hair distribution (kappa= 0.74, P<0.0001). Although a large proportion of subjects in G4 (89.2%) and G5 (85.7%) were capable of accurately or almost accurately identifying their own Tanner sexual stages, some degree of disagreement was observed in G3 Tanner stage (%46.9).

Conclusion

Self-assessment of puberty should be used very cautiously and may not be a substitute method for routine evaluation of pubertal state especially for early and mid pubertal groups.  相似文献   
969.
Introduction: Data on comparison of myo-inositol and metformin on mental health parameters and biomarkers of oxidative stress in subjects with polycystic ovary syndrome (PCOS) are scarce. This purpose of this study was to compare of myo-inositol and metformin on mental health parameters and biomarkers of oxidative stress in subjects with PCOS.

Methods: This randomized controlled trial was conducted among 60 subjects diagnosed with PCOS according to the Rotterdam criteria. Subjects were randomly assigned into two groups to intake either myo-inositol (n?=?30) or metformin (n?=?30) for 12?weeks. Parameters of mental health were recorded at baseline and after the 12-week intervention. Fasting blood samples were obtained at baseline and the end of the study to determine biomarkers of biomarkers of oxidative stress.

Results: After the 12-week intervention, changes in beck depression inventory total score (?1.0?±?1.7 vs. ?0.3?±?0.7, p?=?0.03), general health questionnaire scores (?1.7?±?2.9 vs. ?0.5?±?1.2, p?=?0.02), depression anxiety and stress scale scores (?3.9?±?6.4 vs. ?0.9?±?1.9, p?=?0.01) and plasma total antioxidant capacity (TAC) concentrations (+106.1?±?69.6 vs. +2.1?±?132.4?mmol/L, p?<?0.001) in the myo-inositol group were significantly different from the changes in these indicators in the metformin group. Myo-inositol supplementation for 12?weeks among patients with PCOS did not affect plasma glutathione and malondialdehyde levels.

Conclusions: Overall, our data supported that myo-inositol supplementation for 12?weeks among patients with PCOS had favorable effects on parameters of mental health and plasma TAC levels.  相似文献   
970.

Purpose

To assess the prevalence of and risk factors for female sexual dysfunction (FSD) among women in Birjand city, Iran.

Methods

This cross-sectional population-based survey was conducted in nine areas of Birjand, the provincial center of South Khorasan province and married women aged between 15 and 72 years were included. Data were collected by face-to-face interview and completing a self-administered questionnaire. FSD and related risk factors were assessed.

Results

A total of 821 women with mean age of 31.5 ± 9.1 were studied. Of them, 694 (84.6 %) had active sexual relationship with their husband, 239 (29.1 %) had less than one intercourse per week, 320 (39 %) did not feel pleasure with their sexual activity and intercourse, 86 (10.5 %) had never attained an orgasm, 604 (73.6 %) had a highly satisfactory relationship with their husband.

Conclusions

Dissatisfaction and not feeling pleasure with sexual activity was the most common FSD in our study. Further epidemiologic investigation is clearly warranted.  相似文献   
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