全文获取类型
收费全文 | 39517篇 |
免费 | 3160篇 |
国内免费 | 84篇 |
专业分类
耳鼻咽喉 | 297篇 |
儿科学 | 1791篇 |
妇产科学 | 1208篇 |
基础医学 | 5297篇 |
口腔科学 | 410篇 |
临床医学 | 4733篇 |
内科学 | 7370篇 |
皮肤病学 | 690篇 |
神经病学 | 4568篇 |
特种医学 | 746篇 |
外科学 | 3820篇 |
综合类 | 388篇 |
现状与发展 | 1篇 |
一般理论 | 76篇 |
预防医学 | 5371篇 |
眼科学 | 603篇 |
药学 | 2669篇 |
中国医学 | 39篇 |
肿瘤学 | 2684篇 |
出版年
2024年 | 81篇 |
2023年 | 630篇 |
2022年 | 996篇 |
2021年 | 1965篇 |
2020年 | 1175篇 |
2019年 | 1691篇 |
2018年 | 1899篇 |
2017年 | 1289篇 |
2016年 | 1460篇 |
2015年 | 1515篇 |
2014年 | 1996篇 |
2013年 | 2503篇 |
2012年 | 3623篇 |
2011年 | 3501篇 |
2010年 | 1770篇 |
2009年 | 1512篇 |
2008年 | 2330篇 |
2007年 | 2421篇 |
2006年 | 2057篇 |
2005年 | 1882篇 |
2004年 | 1614篇 |
2003年 | 1347篇 |
2002年 | 1199篇 |
2001年 | 193篇 |
2000年 | 146篇 |
1999年 | 218篇 |
1998年 | 248篇 |
1997年 | 151篇 |
1996年 | 129篇 |
1995年 | 126篇 |
1994年 | 126篇 |
1993年 | 105篇 |
1992年 | 83篇 |
1991年 | 72篇 |
1990年 | 63篇 |
1989年 | 52篇 |
1988年 | 54篇 |
1987年 | 52篇 |
1986年 | 56篇 |
1985年 | 46篇 |
1984年 | 48篇 |
1983年 | 36篇 |
1982年 | 35篇 |
1981年 | 32篇 |
1980年 | 35篇 |
1979年 | 32篇 |
1978年 | 24篇 |
1977年 | 15篇 |
1974年 | 14篇 |
1972年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
Christopher G. Fairburn Sarah L. Welch Phillipa J. Hay 《The International journal of eating disorders》1993,13(2):155-159
It has been suggested that a new diagnostic category be added to the section on eating disorders in DSM-IV. This new diagnosis has been termed binge eating disorder. In this article we argue that for two main reasons it would be a mistake to include binge eating disorder in DSM-IV: first, too little is known about binge eating and other related forms of recurrent overeating to justify its inclusion in DSM-IV; and second, its inclusion would be a source of diagnostic confusion. We argue that it is premature to crystallize this specific subgroup from amongst those who recurrently overeat and that to do so would impede the acquisition of knowledge rather than enhance it. We advocate a research strategy that involves studying broad samples of those with recurrent overeating rather than narrow ones. © 1993 by John Wiley & Sons, Inc. 相似文献
995.
Subha Dahal Ran Cheng Peter K. Cheung Terek Been Ramy Malty Melissa Geng Sarah Manianis Lulzim Shkreta Shahrazad Jahanshahi Johanne Toutant Rose Chan Sean Park Mark A. Brockman Mohan Babu Samira Mubareka Karen Mossman Arinjay Banerjee Scott Gray-Owen Martha Brown Walid A. Houry Benoit Chabot David Grierson Alan Cochrane 《Viruses》2022,14(1)
Medicinal chemistry optimization of a previously described stilbene inhibitor of HIV-1, 5350150 (2-(2-(5-nitro-2-thienyl)vinyl)quinoline), led to the identification of the thiazole-5-carboxamide derivative (GPS491), which retained potent anti-HIV-1 activity with reduced toxicity. In this report, we demonstrate that the block of HIV-1 replication by GPS491 is accompanied by a drastic inhibition of viral gene expression (IC50 ~ 0.25 µM), and alterations in the production of unspliced, singly spliced, and multiply spliced HIV-1 RNAs. GPS491 also inhibited the replication of adenovirus and multiple coronaviruses. Low µM doses of GPS491 reduced adenovirus infectious yield ~1000 fold, altered virus early gene expression/viral E1A RNA processing, blocked viral DNA amplification, and inhibited late (hexon) gene expression. Loss of replication of multiple coronaviruses (229E, OC43, SARS-CoV2) upon GPS491 addition was associated with the inhibition of viral structural protein expression and the formation of virus particles. Consistent with the observed changes in viral RNA processing, GPS491 treatment induced selective alterations in the accumulation/phosphorylation/function of splicing regulatory SR proteins. Our study establishes that a compound that impacts the activity of cellular factors involved in RNA processing can prevent the replication of several viruses with minimal effect on cell viability. 相似文献
996.
Background: Reports indicate patients with feeding difficulties demonstrate signs of inflammation on biopsies, notably eosinophilia, but it is unknown whether mast cell density contributes to variety or volume limitation symptoms. The aim of our study was to evaluate eosinophil and mast cell density of EGD biopsies in pediatric patients with symptoms of decreased volume or variety of ingested foods. Methods: We conducted a single-center, retrospective chart review of EMRs for all new feeding clinic patients between 0 and 17 years of age. Patients were categorized by symptoms at the initial visit as well as eosinophil and mast cell densities in those with EGD biopsies. Ten patients were identified as controls. Results: We identified 30 patients each with volume and variety limitation. Antral mast cell density was increased in 32.1% of variety-limited patients, 37.5% of volume limited patients, and in no controls; Duodenal mast cell density was increased in 32.1% of variety-limited patients, 40.6% of volume-limited patients, and in no controls. Conclusions: In both variety- and volume-limited patients, antral and duodenal mast cell densities were increased. These associations warrant further investigation of the mechanism between mast cells and development of feeding difficulties, allowing more targeted pediatric therapies. 相似文献
997.
Alexander L Lundberg Ramon Lorenzo-Redondo Egon A Ozer Claudia A Hawkins Judd F Hultquist Sarah B Welch PV Vara Prasad James F Oehmke Chad J Achenbach Robert L Murphy Janine I White Robert J Havey Lori Ann Post 《JMIR Public Health and Surveillance》2022,8(1)
BackgroundVariants of the SARS-CoV-2 virus carry differential risks to public health. The Omicron (B.1.1.529) variant, first identified in Botswana on November 11, 2021, has spread globally faster than any previous variant of concern. Understanding the transmissibility of Omicron is vital in the development of public health policy.ObjectiveThe aim of this study is to compare SARS-CoV-2 outbreaks driven by Omicron to those driven by prior variants of concern in terms of both the speed and magnitude of an outbreak.MethodsWe analyzed trends in outbreaks by variant of concern with validated surveillance metrics in several southern African countries. The region offers an ideal setting for a natural experiment given that most outbreaks thus far have been driven primarily by a single variant at a time. With a daily longitudinal data set of new infections, total vaccinations, and cumulative infections in countries in sub-Saharan Africa, we estimated how the emergence of Omicron has altered the trajectory of SARS-CoV-2 outbreaks. We used the Arellano-Bond method to estimate regression coefficients from a dynamic panel model, in which new infections are a function of infections yesterday and last week. We controlled for vaccinations and prior infections in the population. To test whether Omicron has changed the average trajectory of a SARS-CoV-2 outbreak, we included an interaction between an indicator variable for the emergence of Omicron and lagged infections.ResultsThe observed Omicron outbreaks in this study reach the outbreak threshold within 5-10 days after first detection, whereas other variants of concern have taken at least 14 days and up to as many as 35 days. The Omicron outbreaks also reach peak rates of new cases that are roughly 1.5-2 times those of prior variants of concern. Dynamic panel regression estimates confirm Omicron has created a statistically significant shift in viral spread.ConclusionsThe transmissibility of Omicron is markedly higher than prior variants of concern. At the population level, the Omicron outbreaks occurred more quickly and with larger magnitude, despite substantial increases in vaccinations and prior infections, which should have otherwise reduced susceptibility to new infections. Unless public health policies are substantially altered, Omicron outbreaks in other countries are likely to occur with little warning. 相似文献
998.
Jackson R. Taylor Jason G. Wood Evan Mizerak Samuel Hinthorn Julianna Liu Matthew Finn Sarah Gordon Louis Zingas Chengyi Chang Mark A. Klein John M. Denu Vera Gorbunova Andrei Seluanov Jef D. Boeke John M. Sedivy Stephen L. Helfand 《Proceedings of the National Academy of Sciences of the United States of America》2022,119(5)
999.
Wenya Linda Bi Lakshmi Nayak David M Meredith Joseph Driver Ziming Du Samantha Hoffman Yvonne Li Eudocia Quant Lee Rameen Beroukhim Mikael Rinne Ricardo McFaline-Figueroa Ugonma Chukwueke Christine McCluskey Sarah Gaffey Andrew D Cherniack Jennifer Stefanik Lisa Doherty Christina Taubert Meghan Cifrino Deborah LaFrankie Thomas Graillon Patrick Y Wen Keith L Ligon Ossama Al-Mefty Raymond Y Huang Alona Muzikansky E Antonio Chiocca Sandro Santagata Ian F Dunn David A Reardon 《Neuro-oncology》2022,24(1):101
BackgroundProgrammed death ligand 1 (PD-L1) contributes to tumor immunosuppression and is upregulated in aggressive meningiomas. We performed a phase II study of nivolumab, a programmed death 1 (PD-1) blocking antibody among patients with grade ≥2 meningioma that recurred after surgery and radiation therapy.MethodsTwenty-five patients received nivolumab (240 mg biweekly) until progression, voluntary withdrawal, unacceptable toxicity, or death. Tumor mutational burden (TMB) and quantification of tumor-infiltrating lymphocytes (TIL) were evaluated as potential immunocorrelative biomarkers. Change in neurologic function was prospectively assessed using the Neurologic Assessment in Neuro-Oncology (NANO) scale.ResultsEnrolled patients had multiple recurrences including ≥3 prior surgeries and ≥2 prior courses of radiation in 60% and 72%, respectively. Nivolumab was well tolerated with no unexpected adverse events. Six-month progression-free survival (PFS-6) rate was 42.4% (95% CI: 22.8, 60.7) and the median OS was 30.9 months (95% CI: 17.6, NA). One patient achieved radiographic response (ongoing at 4.5 years). TMB was >10/Mb in 2 of 15 profiled tumors (13.3%). Baseline TIL density was low but increased posttreatment in 3 patients including both patients with elevated TMB. Most patients who achieved PFS-6 maintained neurologic function prior to progression as assessed by NANO.ConclusionNivolumab was well tolerated but failed to improve PFS-6, although a subset of patients appeared to derive benefit. Low levels of TMB and TIL density were typically observed. NANO assessment of neurologic function contributed to outcome assessment. Future studies may consider rationally designed combinatorial regimens. 相似文献
1000.
Jonathan L. Temte Shari Barlow Maureen Goss Emily Temte Cristalyne Bell Cecilia He Caroline Hamer Amber Schemmel Bradley Maerz Lily Comp Mitchell Arnold Kimberly Breunig Sarah Clifford Erik Reisdorf Peter Shult Mary Wedig Thomas Haupt James Conway Ronald Gangnon Ashley Fowlkes Amra Uzicanin 《Influenza and other respiratory viruses》2022,16(2):340
BackgroundInfluenza viruses pose significant disease burdens through seasonal outbreaks and unpredictable pandemics. Existing surveillance programs rely heavily on reporting of medically attended influenza (MAI). Continuously monitoring cause‐specific school absenteeism may identify local acceleration of seasonal influenza activity. The Oregon Child Absenteeism Due to Respiratory Disease Study (ORCHARDS; Oregon, WI) implements daily school‐based monitoring of influenza‐like illness‐specific student absenteeism (a‐ILI) in kindergarten through Grade 12 schools and assesses this approach for early detection of accelerated influenza and other respiratory pathogen transmission in schools and surrounding communities.MethodsStarting in September 2014, ORCHARDS combines automated reporting of daily absenteeism within six schools and home visits to school children with acute respiratory infection (ARI). Demographic, epidemiological, and symptom data are collected along with respiratory specimens. Specimens are tested for influenza and other respiratory viruses. Household members can opt into a supplementary household transmission study. Community comparisons are possible using a pre‐existing and highly effective influenza surveillance program, based on MAI at five family medicine clinics in the same geographical area.ResultsOver the first 5 years, a‐ILI occurred on 6634 (0.20%) of 3,260,461 student school days. Viral pathogens were detected in 64.5% of 1728 children with ARI who received a home visit. Influenza was the most commonly detected virus, noted in 23.3% of ill students.ConclusionORCHARDS uses a community‐based design to detect influenza trends over multiple seasons and to evaluate the utility of absenteeism for early detection of accelerated influenza and other respiratory pathogen transmission in schools and surrounding communities. 相似文献