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71.
Ionic liquids are largely used to leach metals from primary (ores) and secondary sources (end-of-life products). However, dry ionic liquids with a carboxylic function on the cation have not yet been used to leach metals at temperature above 100 °C and under atmospheric pressure. The ionic liquid betainium bis(trifluoromethylsulfonyl)imide, [Hbet][Tf2N], was used in the dry state to recover neodymium, dysprosium and cobalt from NdFeB magnets and NdFeB production scrap. The magnets and the scrap were crushed, milled and roasted before being leached above 100 °C. Recovery efficiencies below 10% and a lack of selectivity for all the parameters tested pointed to the importance of water in the dissolution process. The influence of the viscosity of the ionic liquid and the composition of the metal oxides after roasting was investigated as well. Although the dissolution of pure metal oxides was faster than the dissolution of the magnets, the low leaching efficiencies could not be attributed to the composition and crystal structure of the samples, since magnets roasted with the same protocol have already been successfully leached in the past, albeit in the presence of water. The role of water on the mass transfer and on the coordination of the metals was studied by viscometry and by spectroscopic methods, respectively. It is shown that for leaching of rare earths with [Hbet][Tf2N], the presence of ligands such as water is mandatory to saturate the first coordination sphere of the dissolved rare-earth ions. This paper provides new insights in the dissolution mechanism of metal oxides by [Hbet][Tf2N] at leaching temperatures higher than those typically used in hydrometallurgical leaching processes.Recovery of neodymium, dysprosium and cobalt from NdFeB magnets with the dry ionic liquid [Hbet][Tf2N] was investigated at 175 °C and atmospheric pressure. 相似文献
72.
Effects on human heart valve immunogenicity in vitro by high concentration cryoprotectant treatment 下载免费PDF全文
Benjamin A. Högerle Maria Schneider Katrin Sudrow Naima Souidi Meaghan Stolk Isabella Werner Anna Biermann Kelvin G.M. Brockbank Ulrich A. Stock Martina Seifert 《Journal of tissue engineering and regenerative medicine》2018,12(2):e1046-e1055
It has been shown previously that cryopreservation, using an ice‐free cryopreservation method with the cryoprotectant formulation VS83, beneficially modulated immune reactions in vivo and in vitro when compared with conventionally frozen tissues. In this study, we assessed the impact of a VS83 post‐treatment of previously conventionally frozen human tissue on responses of human immune cells in vitro. Tissue punches of treated and non‐treated (control) aortic heart valve tissue (leaflets and associated aortic root) were co‐cultured for 7 days with peripheral blood mononuclear cells or enriched CD14+ monocytes. Effects on cellular activation markers, cytokine secretion and immune cell proliferation were analysed by flow cytometry. Flow cytometry studies showed that VS83 treatment of aortic root tissue promoted activation and differentiation of CD14+ monocytes, inducing both up‐regulation of CD16 and down‐regulation of CD14. Significantly enhanced expression levels for the C‐C chemokine receptor (CCR)7 and the human leukocyte antigen (HLA)‐DR on monocytes co‐cultured with VS83‐treated aortic root tissue were measured, while the interleukin (IL)‐6 and monocyte chemoattractant protein (MCP)‐1 release was suppressed. However, the levels of interferon (IFN)γ and tumour necrosis factor (TNF)α remained undetectable, indicating that complete activation into pro‐inflammatory macrophages did not occur. Similar, but non‐significant, changes occurred with VS83‐treated leaflets. Additionally, in co‐cultures with T cells, proliferation and cytokine secretion responses were minimal. In conclusion, post‐treatment of conventionally cryopreserved human heart valve tissue with the VS83 formulation induces changes in the activation and differentiation characteristics of human monocytes, and thereby may influence long‐term performance following implantation. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
73.
I. Diana Fernandez Nancy P. Chin Carol M. Devine Ann M. Dozier Camille A. Martina Scott McIntosh Kelly Thevenet-Morrison Hongmei Yang 《American journal of public health》2015,105(10):2167-2174
Objectives. We assessed the effects of a worksite multiple-component intervention addressing diet and physical activity on employees’ mean body mass index (BMI) and the percentage of employees who were overweight or obese.Methods. This group-randomized trial (n = 3799) was conducted at 10 worksites in the northeastern United States. Worksites were paired and allocated into intervention and control conditions. Within- and between-groups changes in mean BMIs and in the percentage of overweight or obese employees were examined in a volunteer sample.Results. Within-group mean BMIs decreased by 0.54 kilograms per meter squared (P = .02) and 0.12 kilograms per meter squared (P = .73) at the intervention and control worksites, respectively, resulting in a difference in differences (DID) decrease of 0.42 kilograms per meter squared (P = .33). The within-group percentage of overweight or obese employees decreased by 3.7% (P = .07) at the intervention worksites and increased by 4.9% (P = .1) at the control worksites, resulting in a DID decline of 8.6% (P = .02).Conclusions. Our findings support a worksite population strategy that might eventually reduce the prevalence of overweight and obesity by minimizing environmental exposures to calorically dense foods and increasing exposures to opportunities for energy expenditure within worksite settings.Sixty-eight percent of adults residing in the United States are overweight or obese,1 and these conditions affect more than 1.4 billion adults worldwide.2 Traditional obesity control strategies, which have focused on changing diet and physical activity (PA) behaviors, provide significant individual benefits3 but are considered insufficient to reduce population disease burdens,4,5 for which broad, population-based approaches are needed.6 In addition to individual biology and behaviors, the physical, social, and cultural environment appears to contribute to the upward trend in population estimates of overweight and obesity7,8 by facilitating high-energy, low-nutrient diets and reducing the need to be physically active to perform activities of daily life.9Worksites are feasible self-contained environments with established communication systems in which interventions manipulating the food and PA environment and the social marketing of lifestyle changes can be implemented. Given that 58.4% of the US population aged 16 years or older is employed,10 worksite interventions have the potential to reach large number of adults11 and can foster the participation of employees in project development and sustainability.12–14 Moreover, participatory worksite interventions address workers’ needs, priorities, and interests and allow strategies to be adapted to the realities of individual sites.13 There is also a business case for weight control programs. In comparison with their nonobese counterparts, overweight and obese employees have higher absenteeism rates, have more work limitations, and are less productive.15–18With these issues in mind, the National Heart, Lung, and Blood Institute developed the Obesity Prevention in the Worksite initiative, a population-based approach to promoting behavioral change through environmental interventions that address prevention and control of weight gain.19 Prior to this initiative, worksite trials were either limited scope interventions, targeting a few aspects of the food or PA environment,9,20–23 or broader scope efforts simultaneously targeting risk factors for cardiovascular disease and cancer (e.g., smoking, diet).24–28 In addition, few studies addressed environmental influences related to excessive weight gain.Here we report the results of Images of a Healthy Worksite, one of the studies that is part of the Obesity Prevention in the Worksite initiative; this comprehensive nutrition and PA intervention was designed to promote healthy lifestyles and to stop the shift to the right of the population body mass index (BMI) curve. In this study, worksites were designated to receive an environmental intervention, and employees participated in intervention design. We hypothesized that mean BMIs among employees at the intervention worksites and the percentages of employees who were overweight or obese would not increase over a 2-year period or would increase less than at control worksites. 相似文献
74.
Quantity,quality, and functionality of peripheral blood cells derived from residual blood of different apheresis kits 下载免费PDF全文
75.
Oral cadmium exposure during rat pregnancy: assessment of transplacental micronutrient transport and steroidogenesis at term 下载免费PDF全文
Anja Mikolić Martina Piasek Antonija Sulimanec Grgec Veda M. Varnai Sandra Stasenko Saša Kralik Oguić 《Journal of applied toxicology : JAT》2015,35(5):508-519
Diet is the main source of cadmium (Cd) exposure. Gastrointestinal absorption increases during pregnancy. Cadmium accumulated in the placenta may interfere with nutrient transport to the foetus. Data on the potential of Cd to act as a steroid disruptor of pregnancy are limited. We evaluated the effects of oral Cd exposure during pregnancy on placental function in micronutrient transfer to the foetus and steroidogenesis in Wistar rats (regular 4‐day cyclers) that mated with unexposed males. Pregnant rats were randomly assigned to a Cd group exposed orally to 50 mg Cd l–1 (CdCl2xH2O dissolved in demineralized water), ≈7.5 mg Cd kg–1 a day, during 20 days of gestation and control (supplied with demineralized water). Non‐pregnant rats were treated under the same experimental conditions. On day 20, all of the rats were killed and samples were taken for element analyses (by electrothermal atomic absorption spectrometry). Progesterone and testosterone were measured in serum and placenta‐derived samples (by immunoenzymometric assay and/or enzyme‐linked immunosorbent assay). In the exposed rats, Cd increased in blood and organs, more in pregnant rats, and in placenta and foetus whereas zinc increased in liver. Iron decreased in maternal organs and in foetus, whereas zinc decreased in maternal kidney and placenta. Liver copper was lower and kidney copper higher in all pregnant vs. non‐pregnant rats. Steroids in serum and placenta did not change. In conclusion, oral Cd exposure during rat pregnancy does not affect progesterone and testosterone at term. Transplacental iron and zinc handover are disrupted, which may put at risk the maintenance of foetal nutrition and viability. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
76.
Stephanie M. Lim Aaron C. Brault Geert van Amerongen Angela M. Bosco-Lauth Hannah Romo Varsha D. Sewbalaksing Richard A. Bowen Albert D.M.E. Osterhaus Penelope Koraka Byron E.E. Martina 《Emerging infectious diseases》2015,21(8):1357-1365
West Nile virus (WNV) outbreaks in North America have been characterized by substantial die-offs of American crows (Corvus brachyrhynchos). In contrast, a low incidence of bird deaths has been observed during WNV epidemic activity in Europe. To examine the susceptibility of the western European counterpart of American crows, we inoculated carrion crows (Corvus corone) with WNV strains isolated in Greece (Gr-10), Italy (FIN and Ita09), and Hungary (578/10) and with the highly virulent North American genotype strain (NY99). We also inoculated American crows with a selection of these strains to examine the strains’ virulence in a highly susceptible bird species. Infection with all strains, except WNV FIN, resulted in high rates of death and high-level viremia in both bird species and virus dissemination to several organs. These results suggest that carrion crows are highly susceptible to WNV and may potentially be useful as part of dead bird surveillance for early warning of WNV activity in Europe. 相似文献
77.
78.
Alessandra Elvevi Elena Maria Elli Martina Luc Miki Scaravaglio Fabio Pagni Stefano Ceola Laura Ratti Pietro Invernizzi Sara Massironi 《World journal of gastroenterology : WJG》2022,28(29):3767-3779
Mastocytosis is a rare and heterogeneous disease characterized by various clinical and biological features that affect different prognoses and treatments. The disease is usually divided into 2 principal categories: cutaneous and systemic disease (SM). Clinical features can be related to mast cell (MC) mediator release or pathological MC infiltration. SM is a disease often hard to identify, and the diagnosis is based on clinical, biological, histological, and molecular criteria with different specialists involved in the patient’s clinical work-up. Among all manifestations of the disease, gastrointestinal (GI) symptoms are common, being present in 14%-85% of patients, and can significantly impair the quality of life. Here we review the data regarding GI involvement in SM, in terms of clinical presentations, histological and endoscopic features, the pathogenesis of GI symptoms, and their treatment. 相似文献
79.
Roberta Angelico Bruno Sensi Tommaso M Manzia Giuseppe Tisone Giuseppe Grassi Alessandro Signorello Martina Milana Ilaria Lenci Leonardo Baiocchi 《World journal of gastroenterology : WJG》2021,27(45):7771-7783
Chronic rejection (CR) of liver allografts causes damage to intrahepatic vessels and bile ducts and may lead to graft failure after liver transplantation. Although its prevalence has declined steadily with the introduction of potent immunosuppressive therapy, CR still represents an important cause of graft injury, which might be irreversible, leading to graft loss requiring re-transplantation. To date, we still do not fully appreciate the mechanisms underlying this process. In addition to T cell-mediated CR, which was initially the only recognized type of CR, recently a new form of liver allograft CR, antibody-mediated CR, has been identified. This has indeed opened an era of thriving research and renewed interest in the field. Liver biopsy is needed for a definitive diagnosis of CR, but current research is aiming to identify new non-invasive tools for predicting patients at risk for CR after liver transplantation. Moreover, the minimization or withdrawal of immunosuppressive therapy might influence the establishment of subclinical CR-related injury, which should not be disregarded. Therapies for CR may only be effective in the “early” phases, and a tailored management of the immunosuppression regimen is essential for preventing irreversible liver damage. Herein, we provide an overview of the current knowledge and research on CR, focusing on early detection, identification of non-invasive biomarkers, immuno suppressive management, re-transplantation and future perspectives of CR. 相似文献
80.