全文获取类型
收费全文 | 10792篇 |
免费 | 688篇 |
国内免费 | 65篇 |
专业分类
耳鼻咽喉 | 62篇 |
儿科学 | 243篇 |
妇产科学 | 280篇 |
基础医学 | 1528篇 |
口腔科学 | 396篇 |
临床医学 | 995篇 |
内科学 | 2199篇 |
皮肤病学 | 190篇 |
神经病学 | 1327篇 |
特种医学 | 321篇 |
外科学 | 1252篇 |
综合类 | 24篇 |
现状与发展 | 1篇 |
一般理论 | 8篇 |
预防医学 | 978篇 |
眼科学 | 121篇 |
药学 | 688篇 |
中国医学 | 49篇 |
肿瘤学 | 883篇 |
出版年
2024年 | 17篇 |
2023年 | 121篇 |
2022年 | 247篇 |
2021年 | 422篇 |
2020年 | 256篇 |
2019年 | 392篇 |
2018年 | 428篇 |
2017年 | 340篇 |
2016年 | 393篇 |
2015年 | 366篇 |
2014年 | 461篇 |
2013年 | 603篇 |
2012年 | 867篇 |
2011年 | 846篇 |
2010年 | 452篇 |
2009年 | 425篇 |
2008年 | 671篇 |
2007年 | 638篇 |
2006年 | 627篇 |
2005年 | 569篇 |
2004年 | 533篇 |
2003年 | 471篇 |
2002年 | 383篇 |
2001年 | 115篇 |
2000年 | 82篇 |
1999年 | 109篇 |
1998年 | 58篇 |
1997年 | 69篇 |
1996年 | 39篇 |
1995年 | 34篇 |
1994年 | 31篇 |
1993年 | 24篇 |
1992年 | 51篇 |
1991年 | 64篇 |
1990年 | 33篇 |
1989年 | 40篇 |
1988年 | 32篇 |
1987年 | 33篇 |
1986年 | 27篇 |
1985年 | 25篇 |
1984年 | 25篇 |
1983年 | 8篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 8篇 |
1979年 | 11篇 |
1977年 | 11篇 |
1974年 | 12篇 |
1973年 | 8篇 |
1971年 | 8篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
Chiara Di Lorenzo Francesca Colombo Simone Biella Creina Stockley Patrizia Restani 《Nutrients》2021,13(1)
Polyphenols are a group of phytochemicals with potential health-promoting effects. They are classified as flavonoid (flavonols, flavanols, flavones, flavanones, isoflavones, and anthocyanins) and non-flavonoid molecules (phenolic acids, hydroxycinnamic acids, lignans, stilbenes, and tannins). Although an increasing number of trials have shown a correlation among polyphenol consumption and a reduction in risk factors for chronic diseases, discrepancies in explaining their positive effects have been found in terms of the bioavailability. In fact, polyphenols show a low bioavailability due to several factors: interaction with the food matrix, the metabolic processes mediated by the liver (phase I and II metabolism), intestine and microbiota. On the other hand, the biological activities of phenol compounds may be mediated by their metabolites, which are produced in vivo, and recent studies have confirmed that these molecules may have antioxidant and anti-phlogistic properties. This review discusses the studies performed in vivo, which consider the polyphenol bioavailability and their different food sources. Factors influencing the biological effects of the main classes of polyphenols are also considered. 相似文献
33.
Simone Baldi Marta Menicatti Giulia Nannini Elena Niccolai Edda Russo Federica Ricci Marco Pallecchi Francesca Romano Matteo Pedone Giovanni Poli Daniela Renzi Antonio Taddei Antonino S. Calabr Francesco C. Stingo Gianluca Bartolucci Amedeo Amedei 《Nutrients》2021,13(3)
Altered circulating levels of free fatty acids (FFAs), namely short chain fatty acids (SCFAs), medium chain fatty acids (MCFAs), and long chain fatty acids (LCFAs), are associated with metabolic, gastrointestinal, and malignant diseases. Hence, we compared the serum FFA profile of patients with celiac disease (CD), adenomatous polyposis (AP), and colorectal cancer (CRC) to healthy controls (HC). We enrolled 44 patients (19 CRC, 9 AP, 16 CD) and 16 HC. We performed a quantitative FFA evaluation with the gas chromatography–mass spectrometry method (GC–MS), and we performed Dirichlet-multinomial regression in order to highlight disease-specific FFA signature. HC showed a different composition of FFAs than CRC, AP, and CD patients. Furthermore, the partial least squares discriminant analysis (PLS-DA) confirmed perfect overlap between the CRC and AP patients and separation of HC from the diseased groups. The Dirichlet-multinomial regression identified only strong positive association between CD and butyric acid. Moreover, CD patients showed significant interactions with age, BMI, and gender. In addition, among patients with the same age and BMI, being male compared to being female implies a decrease of the CD effect on the (log) prevalence of butyric acid in FFA composition. Our data support GC–MS as a suitable method for the concurrent analysis of circulating SCFAs, MCFAs, and LCFAs in different gastrointestinal diseases. Furthermore, and notably, we suggest for the first time that butyric acid could represent a potential biomarker for CD screening. 相似文献
34.
Vincenza Gianfredi Annemarie Koster Anna Odone Andrea Amerio Carlo Signorelli Nicolaas C. Schaper Hans Bosma Sebastian Khler Pieter C. Dagnelie Coen D.A. Stehouwer Miranda T. Schram Martien C.J.M. van Dongen Simone J.P.M. Eussen 《Nutrients》2021,13(3)
Our aim was to assess the association between a priori defined dietary patterns and incident depressive symptoms. We used data from The Maastricht Study, a population-based cohort study (n = 2646, mean (SD) age 59.9 (8.0) years, 49.5% women; 15,188 person-years of follow-up). Level of adherence to the Dutch Healthy Diet (DHD), Mediterranean Diet, and Dietary Approaches To Stop Hypertension (DASH) were derived from a validated Food Frequency Questionnaire. Depressive symptoms were assessed at baseline and annually over seven-year-follow-up (using the 9-item Patient Health Questionnaire). We used Cox proportional hazards regression analyses to assess the association between dietary patterns and depressive symptoms. One standard deviation (SD) higher adherence in the DHD and DASH was associated with a lower hazard ratio (HR) of depressive symptoms with HRs (95%CI) of 0.78 (0.69–0.89) and 0.87 (0.77–0.98), respectively, after adjustment for sociodemographic and cardiovascular risk factors. After further adjustment for lifestyle factors, the HR per one SD higher DHD was 0.83 (0.73–0.96), whereas adherence to Mediterranean and DASH diets was not associated with incident depressive symptoms. Higher adherence to the DHD lowered risk of incident depressive symptoms. Adherence to healthy diet could be an effective non-pharmacological preventive measure to reduce the incidence of depression. 相似文献
35.
Joanna Rees Simone Radavelli Bagatini Johnny Lo Jonathan M. Hodgson Claus T. Christophersen Robin M. Daly Dianna J. Magliano Jonathan E. Shaw Marc Sim Catherine P. Bondonno Lauren C. Blekkenhorst Joanne M. Dickson Joshua R. Lewis Amanda Devine 《Nutrients》2021,13(5)
Increasing prevalence of mental health disorders within the Australian population is a serious public health issue. Adequate intake of fruits and vegetables (FV), dietary fibre (DF) and resistant starch (RS) is associated with better mental and physical health. Few longitudinal studies exist exploring the temporal relationship. Using a validated food frequency questionnaire, we examined baseline FV intakes of 5845 Australian adults from the AusDiab study and estimated food group-derived DF and RS using data from the literature. Perceived mental health was assessed at baseline and 5 year follow up using SF-36 mental component summary scores (MCS). We conducted baseline cross-sectional analysis and prospective analysis of baseline dietary intake with perceived mental health at 5 years. Higher baseline FV and FV-derived DF and RS intakes were associated with better 5 year MCS (p < 0.001). A higher FV intake (754 g/d vs. 251 g/d, Q4 vs. Q1) at baseline had 41% lower odds (OR = 0.59: 95% CI 0.46–0.75) of MCS below population average (<47) at 5 year follow up. Findings were similar for FV-derived DF and RS. An inverse association was observed with discretionary food-derived DF and RS. This demonstrates the association between higher intakes of FV and FV-derived DF and RS with better 5 year mental health outcomes. Further RCTs are necessary to understand mechanisms that underlie this association including elucidation of causal effects. 相似文献
36.
Alice Ramondetta Simone Ribero Pietro Quaglino Paolo Broganelli 《Emerging infectious diseases》2021,27(1):281
Fluorescence-advanced videodermatoscopy is not a widespread diagnostic technique. Its application in dermatology can facilitate the diagnosis of diseases such as cutaneous larva migrans by enabling us to recognize the precise position of larva in vivo on the skin. Using this noninvasive technique, we detected a case of cutaneous larva migrans in a patient. 相似文献
37.
Lobo Sylvia J. Lin Jessica G. Vais Simone Wang Dongyu Adegoke Tejumola M. Wu Wan-Ju Steer-Massaro Courtney 《Journal of immigrant and minority health / Center for Minority Public Health》2022,24(1):111-117
Journal of Immigrant and Minority Health - Although multiple studies have shown that resettled refugee women are less likely to receive preventative cancer screenings like pap smears and... 相似文献
38.
Carlo Giulioni Valentina Maurizi Simone Scarcella Manuel Di Biase Valerio Iacovelli Andrea Benedetto Galosi Daniele Castellani 《Andrologia》2021,53(11):e14215
Our purpose was to review and analyse the impact of pyrethroids and organophosphates exposure on human semen parameters. A comprehensive literature search was performed through MEDLINE via PubMed, Scopus and Webscience. Only cohort studies examining semen parameters in workers or general populations exposed to pyrethroids or organophosphates were included. Ejaculate volume, sperm count, concentration, motility, viability, normal morphology and seminal pH alterations were pooled using the Cochran–Mantel–Haenszel Method with the random effect model and expressed as weighted mean difference, risk ratios, 95% confidence intervals and p-values. Seven cross-sectional studies regarding pyrethroids were included. Four of them were eligible for meta-analysis. The only parameter affected by pyrethroid exposure was normal sperm morphology (WMD-7,61%, 95%CI –11,92 to −3,30;p = 0,0,005). Nine studies were selected to evaluate the impact of organophosphates on semen parameters with six of them eligible for meta-analysis. A significant reduction was detected for the following: ejaculate volume (WMD −0,47ml, 95%CI −0,69 to −0,25; p < 0,0001), sperm count (WMD-40,03, 95%CI −66,81 to −13,25;p = 0,003), concentration (WMD-13,69 x10⁶/mL, 95%CI −23, 27 to-4,12;p = 0,005) and motility (WMD −5,70%, 95%CI −12,89 to 1,50;p = 0,12). Despite the increase in sperm abnormality, it has been shown that pyrethroids are unrelated to reduced sperm quality. However, the negative association of organophosphates with spermatogenesis is noteworthy. 相似文献
39.
Luigi Gennari Daniela Merlotti Natale Figura Christian Mingiano Maria Beatrice Franci Barbara Lucani Tommaso Picchioni Mario Alessandri Maria Stella Campagna Sara Gonnelli Simone Bianciardi Maria Materozzi Carla Caffarelli Stefano Gonnelli Ranuccio Nuti 《Journal of bone and mineral research》2021,36(1):80-89
Helicobacter pylori (HP) infection is a common and persistent disorder acting as a major cofactor for the development of upper gastrointestinal diseases and several extraintestinal disorders including osteoporosis. However, no prospective study assessed the effects of HP on bone health and fracture risk. We performed a HP screening in a population-based cohort of 1149 adults followed prospectively for up to 11 years. The presence of HP infection was assessed by serologic testing for serum antibodies to HP and the cytotoxin associated gene-A (CagA). The prevalence of HP infection did not differ among individuals with normal bone mineral density (BMD), osteoporosis, and osteopenia. However, HP infection by CagA-positive strains was significantly increased in osteoporotic (30%) and osteopenic (26%) patients respect to subjects with normal BMD (21%). Moreover, anti-CagA antibody levels were significantly and negatively associated with lumbar and femoral BMD. Consistent with these associations, patients affected by CagA-positive strains had a more than fivefold increased risk to sustain a clinical vertebral fracture (HR 5.27; 95% CI, 2.23–12.63; p < .0001) and a double risk to sustain a nonvertebral incident fracture (HR 2.09; 95% CI, 1.27–2.46; p < .005). Reduced estrogen and ghrelin levels, together with an impaired bone turnover balance after the meal were also observed in carriers of CagA-positive HP infection. HP infection by strains expressing CagA may be considered a risk factor for osteoporosis and fractures. Further studies are required to clarify in more detail the underlying pathogenetic mechanisms of this association. © 2020 American Society for Bone and Mineral Research (ASBMR). 相似文献
40.
Andrea D’Ambrosio Caroline Toulouse Samuel Bélanger-Marceau Simone Savary Sunita Mathur Bianca Segatto David Hartell Tania Janaudis-Ferreira 《Transplantation proceedings》2021,53(2):581-589
BackgroundThe Canadian Transplant games (“Games”) were created to increase awareness of organ donation and highlight the importance of staying active and healthy post-transplant. It is unclear what motivates solid organ transplant (SOT) recipients to participate and whether the games serve as an incentive for SOT recipients to increase their physical activity (PA) levels.Objectives1. To describe the characteristics of participants from past games and their motivation for attending and 2. to determine whether there was an interest in participating in goal-based, pre-games exercise training programs.MethodsA web-based questionnaire was sent to adult SOT recipients who were members of the Canadian Transplant Association. The survey included questions about why participants attended, their PA levels, and their interest in a pre-games training program.ResultsOf the 157 participants, more were male than female; the 35-54-year-old age group was the most common; and 62% of respondents received a liver or kidney transplant. The most common reasons for participating in the games were to showcase health post-transplant, promote awareness of organ donation, sports competition, and social reasons. Sixty-five percent of respondents reported that they would be interested in an exercise program to be more physically prepared for the competition.ConclusionPre-games training programs could be developed to motivate participation and help participants achieve higher training intensities and foster social interaction. Directing resources to individuals who do not attend the games and to those who are not physically active should be considered. 相似文献