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41.
A growing health concern, due to poor air quality, recently led to an increased number of studies regarding air pollution effects on public health. Consequently, close attention is paid to estimation methods of exposure to atmospheric pollutants. This paper aims to meet a specific requirement of epidemiological researchers, that is providing annual air pollution maps at municipality scale for health impact assessment purposes on national basis. Firstly, data fusion through kriging with external drift is implemented, combining pollution data from two different sources, models and measurements, in order to improve the spatial distribution of surface concentrations at grid level. Then, the assimilated data of air pollution are upscaled, so as to obtain concentrations at municipality level. This methodology was applied to Italy and Spain (in Spain, only the second step was carried out since the modeled concentration already included an assimilation procedure). In both countries, for each municipality, an estimate of the concentration value for atmospheric pollutants of major concern for human health (PM10 and NO2) was provided, offering more relevant information from a surveillance point of view.  相似文献   
42.

Background

A significant challenge in Patient and Public Involvement and Engagement (PPIE) in health research is to include a wide range of opinions and experiences, including from those who repeatedly find themselves at the margins of society.

Objective

To contribute to the debate around PPIE by introducing a bottom‐up methodology: cultural animation (CA). Cultural Animation is an arts‐based methodology of knowledge co‐production and community engagement which employs a variety of creative and participatory exercises to help build trusting relationships between diverse participants (expert and non‐experts) and democratize the process of research.

Design

Three CA full‐day workshops for the research project “A Picture of Health.”

Participants

Each workshop was attended by 20‐25 participants including 4 academics, 5 retired health professionals who volunteered in the local community and 15 community members. Participants ranged in age from 25 to 75 years, and 80% of the participants were women over the age of 60.

Results

The CA workshops unearthed a diversity of hidden assets, increased human connectivity, led to rethinking of and co‐creating new health indicators and enabled participants to think of community health in a positive way and to consider what can be developed.

Discussion

Cultural animation encourages participants to imagine and create ideal pictures of health by experimenting with new ways of working together.

Conclusion

We conclude by highlighting the main advantages to PPIE as follows: CA provides a route to co‐produce research agendas, empowers the public to engage actively with health professionals and make a positive contribution to their community.  相似文献   
43.
[13CD3]‐TAK‐459 (1A), an HSP90 inhibitor, was synthesized from [13CD3]‐sodium methoxide in three steps in an overall yield of 29%. The key intermediate [13CD3]‐2‐methoxy‐6‐(4,4,5,5‐tetramethyl‐1,3,2‐dioxaborolan‐2‐yl)pyridine was synthesized in two steps from 2,6‐dibromopyridine and stable isotope‐labeled sodium methoxide. [14C]‐TAK‐459 (1B) was synthesized from [14C(U)]‐guanidine hydrochloride in five steps in an overall radiochemical yield of 5.4%. The key intermediate, [14C]‐(R)‐2‐amino‐7‐(2‐bromo‐4‐fluorophenyl)‐4‐methyl‐7,8‐dihydropyrido[4,3‐d]pyrimidin‐5(6H)‐one, was prepared by microwave‐assisted condensation.  相似文献   
44.
Dentin and enamel loss related to trauma or especially caries is one of the most common pathological issues in dentistry that requires restoration of the teeth by using materials with appropriate properties. The composite resins represent dental materials with significant importance in today’s dentistry, presenting important qualities, including their mechanical behavior and excellent aesthetics. This paper focuses on the saliva interactions with these materials and on their biocompatibility, which is continuously improved in the new generations of resin-based composites. Starting from the elements involved on the molecular landscape of the dental caries process, the paper presents certain strategies for obtaining more advanced new dental composite resins, as follows: suppression of oral biofilm acids formation, promotion of remineralization process, counteraction of the proteolytic attack, and avoidance of cytotoxic effects; the relation between dental composite resins and salivary oxidative stress biomarkers is also presented in this context.  相似文献   
45.
With the development of the modern concept of tissue engineering approach and the discovery of the potential of stem cells in dentistry, the regeneration of hard dental tissues has become a reality and a priority of modern dentistry. The present review reports the recent advances on stem-cell based regeneration strategies for hard dental tissues and analyze the feasibility of stem cells and of growth factors in scaffolds-based or scaffold-free approaches in inducing the regeneration of either the whole tooth or only of its component structures.  相似文献   
46.
There is debate concerning the involvement of p38 mitogen activated protein kinase (MAPK) in the mediation of ischaemic preconditioning. Pharmacological inhibition of p38 MAPK with SB203580 has been reported to block preconditioning in some studies but not in others. We hypothesised that this divergence could be due to differences in the timing of inhibitor administration. Isolated rat hearts were perfused in the Langendorff mode and subjected to 35 min regional ischaemia followed by 120 min reperfusion. Hearts were then double stained with Evans' blue and triphenyltetrazolium chloride to determine risk (R) and infarct zones (I), expressed as I/R% ratios. Preconditioned hearts were subjected to 2 times 5 min global ischaemia with 10 min intervening reperfusion. SB203580 10 μ M was perfused either during the preconditioning protocol (PC+SB-early), just prior to and during the first 15 min of the lethal ischaemia (PC+SB-late) or prior to regional ischaemia in the absence of preconditioning. Ischaemic preconditioning significantly limited infarct size (I/R 38.9 ± 3.0% in control vs 13.4 ± 2.4%, P < 0.01). In the PC+SB-early group, preconditioning was still fully protective (I/R% 14.6 ± 1.0). However, in the PC+SB-late group, SB203580 completely blocked the protection afforded by preconditioning (I/R% 33.6 ± 4.4%, P < 0.01 vs 13.4 ± 2.4% in preconditioned hearts, p < 0.05). SB203580 alone did not affect infarct size when given prior to and during regional ischaemia (I/R 36.2 ± 2.7%). These histological data are corroborated by a significant increase in p38 MAPK activation in the preconditioned hearts during sustained ischaemia in comparison with the controls. In conclusion the activation of p38 MAPK during lethal ischaemia, but not during the ischaemic preconditioning protocol, is essential for the mediation of protection and may resolve some of the earlier controversy surrounding the use of SB203580 in preconditioning studies. Received: 28 June 2000, Returned for revision: 21 July 2000, Revision received: 9 August 2000, Accepted: 13 September 2000  相似文献   
47.
48.
Magnesium may contribute to the immune response during and after SARS-CoV-2 infection by acting as a cofactor for immunoglobulin production and other processes required for T and B cell activity. Considering magnesium as a recommended dietary supplement during pregnancy and the possible role of magnesium deficiency in COVID-19 and its complications, the current study sought to determine the effect of magnesium and magnesium-containing nutritional supplements on the immune response following SARS-CoV-2 infection in pregnant women, as well as to observe differences in pregnancy outcomes based on the supplements taken during pregnancy. The study followed a cross-sectional design, where patients with a history of SARS-CoV-2 infection during their pregnancy were surveyed for their preferences in nutritional supplementation and their profile compared with existing records from the institutional database. A cohort of 448 pregnant women with COVID-19 during 22 months of the pandemic was assembled, out of which 13.6% took a magnesium-only supplement, and 16.5% supplemented their diet with a combination of calcium, magnesium, and zinc. Around 60% of patients in the no-supplementation group had the SARS-CoV-2 anti-RBD lower than 500 U/mL, compared with 50% in those who took magnesium-based supplements. A quantity of magnesium >450 mg in the taken supplements determined higher levels of antibody titers after COVID-19. Low magnesium dosage (<450 mg) was an independent risk factor for a weak immune response (OR-1.25, p-value = 0.003). The observed findings suggest supplementing the nutritional intake of pregnant women with magnesium-based supplements to determine higher levels of SARS-CoV-2 anti-RBD antibodies, although causality remains unclear.  相似文献   
49.
In this study, we aim to obtain biomaterials with antibacterial properties by combining poly(vinyl alcohol) with the extracts obtained from various selected plants from Romania. Natural herbal extracts of freshly picked flowers of the lavender plant (Lavandula angustifolia) and leaves of the peppermint plant (Mentha piperita), hemp plant (Cannabis sativa L.), verbena plant (Verbena officinalis) and sage plant (Salvia officinalis folium) were selected after an intensive analyzing of diverse medicinal plants often used as antibacterial and healing agents from the country flora. The plant extracts were characterized by different methods such as totals of phenols and flavonoids content and UV-is spectroscopy. The highest amounts of the total phenolic and flavonoid contents, respectively, were recorded for Salvia officinalis. Moreover, the obtained films of poly(vinyl alcohol) (PVA) loaded with plant extracts were studied concerning the surface properties and their antibacterial or cytotoxicity activity. The Attenuated Total Reflection Fourier Transform Infrared analysis described the successfully incorporation of each plant extract in the poly(vinyl alcohol) matrix, while the profilometry demonstrated the enhanced surface properties. The results showed that the plant extracts conferred significant antibacterial effects to films toward Staphylococcus aureus and Escherichia coli and are not toxic against fibroblastic cells from the rabbit.  相似文献   
50.
Polyhydroxyalkanoates (PHAs) are biodegradable and biocompatible biopolymers. These biomaterials have grown in importance in the fields of tissue engineering and tissue reconstruction for structural applications where tissue morphology is critical, such as bone, cartilage, blood vessels, and skin, among others. Furthermore, they can be used to accelerate the regeneration in combination with drugs, as drug delivery systems, thus reducing microbial infections. When cells are cultured under stress conditions, a wide variety of microorganisms produce them as a store of intracellular energy in the form of homo- and copolymers of [R]—hydroxyalkanoic acids, depending on the carbon source used for microorganism growth. This paper gives an overview of PHAs, their biosynthetic pathways, producing microorganisms, cultivation bioprocess, isolation, purification and characterization to obtain biomaterials with medical applications such as tissue engineering.  相似文献   
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