全文获取类型
收费全文 | 133003篇 |
免费 | 7369篇 |
国内免费 | 761篇 |
专业分类
耳鼻咽喉 | 1344篇 |
儿科学 | 4264篇 |
妇产科学 | 3048篇 |
基础医学 | 18897篇 |
口腔科学 | 4427篇 |
临床医学 | 12032篇 |
内科学 | 30040篇 |
皮肤病学 | 3480篇 |
神经病学 | 12592篇 |
特种医学 | 3204篇 |
外国民族医学 | 2篇 |
外科学 | 12726篇 |
综合类 | 514篇 |
一般理论 | 59篇 |
预防医学 | 13071篇 |
眼科学 | 2273篇 |
药学 | 9079篇 |
中国医学 | 508篇 |
肿瘤学 | 9573篇 |
出版年
2024年 | 137篇 |
2023年 | 1204篇 |
2022年 | 2587篇 |
2021年 | 4412篇 |
2020年 | 2644篇 |
2019年 | 3730篇 |
2018年 | 4300篇 |
2017年 | 3137篇 |
2016年 | 3622篇 |
2015年 | 4057篇 |
2014年 | 5434篇 |
2013年 | 7104篇 |
2012年 | 10637篇 |
2011年 | 11190篇 |
2010年 | 6121篇 |
2009年 | 5187篇 |
2008年 | 8929篇 |
2007年 | 8935篇 |
2006年 | 8248篇 |
2005年 | 7812篇 |
2004年 | 7013篇 |
2003年 | 6338篇 |
2002年 | 5758篇 |
2001年 | 1064篇 |
2000年 | 905篇 |
1999年 | 1061篇 |
1998年 | 1022篇 |
1997年 | 825篇 |
1996年 | 711篇 |
1995年 | 594篇 |
1994年 | 569篇 |
1993年 | 456篇 |
1992年 | 550篇 |
1991年 | 404篇 |
1990年 | 413篇 |
1989年 | 358篇 |
1988年 | 359篇 |
1987年 | 295篇 |
1986年 | 296篇 |
1985年 | 243篇 |
1984年 | 253篇 |
1983年 | 205篇 |
1982年 | 205篇 |
1981年 | 164篇 |
1980年 | 168篇 |
1979年 | 158篇 |
1978年 | 126篇 |
1977年 | 114篇 |
1976年 | 107篇 |
1974年 | 108篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Richard A. Oram Seth A. Sharp Catherine Pihoker Lauric Ferrat Giuseppina Imperatore Adrienne Williams Maria J. Redondo Lynne Wagenknecht Lawrence M. Dolan Jean M. Lawrence Michael N. Weedon Ralph DAgostino Jr. William A. Hagopian Jasmin Divers Dana Dabelea 《Diabetes care》2022,45(5):1124
OBJECTIVEGenetic risk scores (GRS) aid classification of diabetes type in White European adult populations. We aimed to assess the utility of GRS in the classification of diabetes type among racially/ethnically diverse youth in the U.S.RESEARCH DESIGN AND METHODSWe generated type 1 diabetes (T1D)- and type 2 diabetes (T2D)-specific GRS in 2,045 individuals from the SEARCH for Diabetes in Youth study. We assessed the distribution of genetic risk stratified by diabetes autoantibody positive or negative (DAA+/−) and insulin sensitivity (IS) or insulin resistance (IR) and self-reported race/ethnicity (White, Black, Hispanic, and other).RESULTST1D and T2D GRS were strong independent predictors of etiologic type. The T1D GRS was highest in the DAA+/IS group and lowest in the DAA−/IR group, with the inverse relationship observed with the T2D GRS. Discrimination was similar across all racial/ethnic groups but showed differences in score distribution. Clustering by combined genetic risk showed DAA+/IR and DAA−/IS individuals had a greater probability of T1D than T2D. In DAA− individuals, genetic probability of T1D identified individuals most likely to progress to absolute insulin deficiency.CONCLUSIONSDiabetes type–specific GRS are consistent predictors of diabetes type across racial/ethnic groups in a U.S. youth cohort, but future work needs to account for differences in GRS distribution by ancestry. T1D and T2D GRS may have particular utility for classification of DAA− children. 相似文献
992.
Francesco Cogliati Dezza Alessandra Oliva Vera Mauro Francesco Eugenio Romani Raissa Aronica Giulia Savelloni Elena Casali Serena Valeri Francesca Cancelli Claudio Maria Mastroianni 《Le infezioni in medicina : rivista periodica di eziologia, epidemiologia, diagnostica, clinica e terapia delle patologie infettive》2022,30(2):211
993.
Chiara Delli Poggi Maria Fusaro Maria Cristina Mereu Maria Luisa Brandi Luisella Cianferotti 《Nutrients》2022,14(12)
Both osteoporosis with related fragility fractures and cardiovascular diseases are rapidly outspreading worldwide. Since they are often coexistent in elderly patients and may be related to possible common pathogenetic mechanisms, the possible reciprocal effects of drugs employed to treat these diseases have to be considered in clinical practice. Bisphosphonates, the agents most largely employed to decrease bone fragility, have been shown to be overall safe with respect to cardiovascular diseases and even capable of reducing cardiovascular morbidity in some settings, as mainly shown by real life studies. No randomized controlled trials with cardiovascular outcomes as primary endpoints are available. While contradictory results have emerged about a possible BSP-mediated reduction of overall mortality, it is undeniable that these drugs can be employed safely in patients with high fracture risk, since no increased mortality has ever been demonstrated. Although partial reassurance has emerged from meta-analysis assessing the risk of cardiac arrhythmias during bisphosphonates treatment, caution is warranted in administering this class of drugs to patients at risk for atrial fibrillation, possibly preferring other antiresorptives or anabolics, according to osteoporosis guidelines. This paper focuses on the complex relationship between bisphosphonates use and cardiovascular disease and possible co-management issues. 相似文献
994.
Ravi Mahalingam Brittany Feia Colin Coleman Kusala Anupindi Pratush Saravanan Amalia Luthens Amalia Bustillos Arpita Das Eileen de Haro Lara Doyle-Meyers Jayme Looper Andrew N. Bubak Christy S. Niemeyer Brent Palmer Maria A. Nagel Vicki Traina-Dorge 《Viruses》2022,14(6)
Primary simian varicella virus (SVV) infection and reactivation in nonhuman primates is a valuable animal model in the study of varicella zoster virus disease [varicella (chickenpox) and herpes zoster (shingles)]. To understand SVV pathogenesis in skin, we inoculated 10 rhesus macaques with SVV, resulting in varicella rash. After the establishment of latency, eight of the monkeys were immunosuppressed using tacrolimus with or without irradiation and prednisone and two monkeys were not immunosuppressed. Zoster rash developed in all immunosuppressed monkeys and in one non-immunosuppressed monkey. Five monkeys had recurrent zoster. During varicella and zoster, SVV DNA in skin scrapings ranged from 50 to 107 copies/100 ng of total DNA and 2–127 copies/100 ng of total DNA, respectively. Detection of SVV DNA in blood during varicella was more frequent and abundant compared to that of zoster. During varicella and zoster, SVV antigens colocalized with neurons expressing β-III tubulin in epidermis, hair follicles, and sweat glands, suggesting axonal transport of the virus. Together, we have demonstrated that both SVV DNA and antigens can be detected in skin lesions during varicella and zoster, providing the basis for further studies on SVV skin pathogenesis, including immune responses and mechanisms of peripheral spread. 相似文献
995.
Daniela Campaniello Maria Rosaria Corbo Milena Sinigaglia Barbara Speranza Angela Racioppo Clelia Altieri Antonio Bevilacqua 《Nutrients》2022,14(12)
Gut microbiota plays a significant role in the maintenance of physiological homeostasis, contributing to human health. Nevertheless, some factors (sex, age, lifestyle, physical activity, drug-based therapies, diet, etc.) affect its composition and functionality, linked to pathologies and immunological diseases. Concerning diet, it interacts with microorganisms, leading to beneficial or detrimental outcomes for the health of host. On the other hand, physical activity is known to be useful for preventing and, sometimes, treating several diseases of cardiovascular, neuroendocrine, respiratory, and muscular systems. This paper focuses on diet and physical activity presenting the current knowledge about how different diets (Western, ketogenic, vegan, gluten free, Mediterranean) as well as different types of exercise (intensive, endurance, aerobic) could shape gut microbiota. 相似文献
996.
Piero Portincasa Giuseppe Celano Nadia Serale Paola Vitellio Francesco Maria Calabrese Alexandra Chira Liliana David Dan L. Dumitrascu Maria De Angelis 《Nutrients》2022,14(12)
Fructose intolerance (FI) is a widespread non-genetic condition in which the incomplete absorption of fructose leads to gastro-intestinal disorders. The crucial role of microbial dysbiosis on the onset of these intolerance symptoms together with their persistence under free fructose diets are driving the scientific community towards the use of probiotics as a novel therapeutic approach. In this study, we evaluated the prevalence of FI in a cohort composed of Romanian adults with Functional Grastrointestinal Disorders (FGIDs) and the effectiveness of treatment based on the probiotic formulation EQBIOTA® (Lactiplantibacillus plantarum CECT 7484 and 7485 and Pediococcus acidilactici CECT 7483). We evaluated the impact of a 30-day treatment both on FI subjects and healthy volunteers. The gastrointestinal symptoms and fecal volatile metabolome were evaluated. A statistically significant improvement of symptoms (i.e., bloating, and abdominal pain) was reported in FI patient after treatment. On the other hand, at the baseline, the content of volatile metabolites was heterogeneously distributed between the two study arms, whereas the treatment led differences to decrease. From our analysis, how some metabolomics compounds were correlated with the improvement and worsening of clinical symptoms clearly emerged. Preliminary observations suggested how the improvement of gastrointestinal symptoms could be induced by the increase of anti-inflammatory and protective substrates. A deeper investigation in a larger patient cohort subjected to a prolonged treatment would allow a more comprehensive evaluation of the probiotic treatment effects. 相似文献
997.
Pragney Deme Leah H. Rubin Danyang Yu Yanxun Xu Gertrude Nakigozi Noeline Nakasujja Aggrey Anok Alice Kisakye Thomas C. Quinn Steven J. Reynolds Richard Mayanja James Batte Maria J. Wawer Ned C. Sacktor Deanna Saylor Norman J. Haughey 《Viruses》2022,14(6)
Background: HIV infection results in immunometabolic reprogramming. While we are beginning to understand how this metabolic reprogramming regulates the immune response to HIV infection, we do not currently understand the impact of ART on immunometabolism in people with HIV (PWH). Methods: Serum obtained from HIV-infected (n = 278) and geographically matched HIV seronegative control subjects (n = 300) from Rakai Uganda were used in this study. Serum was obtained before and ~2 years following the initiation of ART from HIV-infected individuals. We conducted metabolomics profiling of the serum and focused our analysis on metabolic substrates and pathways assocaited with immunometabolism. Results: HIV infection was associated with metabolic adaptations that implicated hyperactive glycolysis, enhanced formation of lactate, increased activity of the pentose phosphate pathway (PPP), decreased β-oxidation of long-chain fatty acids, increased utilization of medium-chain fatty acids, and enhanced amino acid catabolism. Following ART, serum levels of ketone bodies, carnitine, and amino acid metabolism were normalized, however glycolysis, PPP, lactate production, and β-oxidation of long-chain fatty acids remained abnormal. Conclusion: Our findings suggest that HIV infection is associated with an increased immunometabolic demand that is satisfied through the utilization of alternative energetic substrates, including fatty acids and amino acids. ART alone was insufficient to completely restore this metabolic reprogramming to HIV infection, suggesting that a sustained impairment of immunometabolism may contribute to chronic immune activation and comorbid conditions in virally suppressed PWH. 相似文献
998.
Diana Erazo Maria F. Vincenti-Gonzalez Joris A. F. van Loenhout Pierre Hubin Mathil Vandromme Piet Maes Maxime Taquet Johan Van Weyenbergh Lucy Catteau Simon Dellicour 《Viruses》2022,14(6)
The national vaccination campaign against SARS-CoV-2 started in January 2021 in Belgium. In the present study, we aimed to use national hospitalisation surveillance data to investigate the recent evolution of vaccine impact on the risk of COVID-19 hospitalisation. We analysed aggregated data from 27,608 COVID-19 patients hospitalised between October 2021 and February 2022, stratified by age category and vaccination status. For each period, vaccination status, and age group, we estimated risk ratios (RR) corresponding to the ratio between the probability of being hospitalised following SARS-CoV-2 infection if belonging to the vaccinated population and the same probability if belonging to the unvaccinated population. In October 2021, a relatively high RR was estimated for vaccinated people > 75 years old, possibly reflecting waning immunity within this group, which was vaccinated early in 2021 and invited to receive the booster vaccination at that time. In January 2022, a RR increase was observed in all age categories coinciding with the dominance of the Omicron variant. Despite the absence of control for factors like comorbidities, previous infections, or time since the last administered vaccine, we showed that such real-time aggregated data make it possible to approximate trends in vaccine impact over time. 相似文献
999.
1000.
Kristine Korzow Richter Maria C. Codlin Melina Seabrook Christina Warinner 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(20)
Collagen peptide mass fingerprinting by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry, also known as zooarchaeology by mass spectrometry (ZooMS), is a rapidly growing analytical technique in the fields of archaeology, ecology, and cultural heritage. Minimally destructive and cost effective, ZooMS enables rapid taxonomic identification of large bone assemblages, cultural heritage objects, and other organic materials of animal origin. As its importance grows as both a research and a conservation tool, it is critical to ensure that its expanding body of users understands its fundamental principles, strengths, and limitations. Here, we outline the basic functionality of ZooMS and provide guidance on interpreting collagen spectra from archaeological bones. We further examine the growing potential of applying ZooMS to nonmammalian assemblages, discuss available options for minimally and nondestructive analyses, and explore the potential for peptide mass fingerprinting to be expanded to noncollagenous proteins. We describe the current limitations of the method regarding accessibility, and we propose solutions for the future. Finally, we review the explosive growth of ZooMS over the past decade and highlight the remarkably diverse applications for which the technique is suited. 相似文献