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991.
Marcin Hoffmann Krzysztof arkiewicz Adam Zieliski Szymon Skibicki ukasz Marchewka 《Materials》2021,14(10)
Foundation piles that are made by concrete 3D printers constitute a new alternative way of founding buildings constructed using incremental technology. We are currently observing very rapid development of incremental technology for the construction industry. The systems that are used for 3D printing with the application of construction materials make it possible to form permanent formwork for strip foundations, construct load-bearing walls and partition walls, and prefabricate elements, such as stairs, lintels, and ceilings. 3D printing systems do not offer soil reinforcement by making piles. The paper presents the possibility of making concrete foundation piles in laboratory conditions using a concrete 3D printer. The paper shows the tools and procedure for pile pumping. An experiment for measuring pile bearing capacity is described and an example of a pile deployment model under a foundation is described. The results of the tests and analytical calculations have shown that the displacement piles demonstrate less settlement when compared to the analysed shallow foundation. The authors indicate that it is possible to replace the shallow foundation with a series of piles combined with a printed wall without locally widening it. This type of foundation can be used for the foundation of low-rise buildings, such as detached houses. Estimated calculations have shown that the possibility of making foundation piles by a 3D printer will reduce the cost of making foundations by shortening the time of execution of works and reducing the consumption of construction materials. 相似文献
992.
Oleksandr Shtyka Waldemar Maniukiewicz Radoslaw Ciesielski Adam Kedziora Viktar Shatsila Tomasz Sieraski Tomasz Maniecki 《Materials》2021,14(12)
In the present work, for the first time, the possibility of formation of CrAl2O4 was shown from the equimolar mixture of co-precipitated Al2O3 and Cr2O3 oxides under a reductive environment. The crystallographic properties of the formed compound were calculated using the DICVOL procedure. It was determined that it has a cubic crystal structure with space group Fd-3m and a unit cell parameter equal to 8.22(3) Å. The formed CrAl2O4 is not stable under ambient conditions and easily undergoes oxidation to α-Al2O3 and α-Cr2O3. The overall sequence of the phase transformations of co-precipitated oxides leading to the formation of spinel structure is proposed. 相似文献
993.
Valentina Baena Ryan Conrad Patrick Friday Ella Fitzgerald Taeeun Kim John Bernbaum Heather Berensmann Adam Harned Kunio Nagashima Kedar Narayan 《Viruses》2021,13(4)
The visualization of cellular ultrastructure over a wide range of volumes is becoming possible by increasingly powerful techniques grouped under the rubric “volume electron microscopy” or volume EM (vEM). Focused ion beam scanning electron microscopy (FIB-SEM) occupies a “Goldilocks zone” in vEM: iterative and automated cycles of milling and imaging allow the interrogation of microns-thick specimens in 3-D at resolutions of tens of nanometers or less. This bestows on FIB-SEM the unique ability to aid the accurate and precise study of architectures of virus-cell interactions. Here we give the virologist or cell biologist a primer on FIB-SEM imaging in the context of vEM and discuss practical aspects of a room temperature FIB-SEM experiment. In an in vitro study of SARS-CoV-2 infection, we show that accurate quantitation of viral densities and surface curvatures enabled by FIB-SEM imaging reveals SARS-CoV-2 viruses preferentially located at areas of plasma membrane that have positive mean curvatures. 相似文献
994.
Francisco Javier Candel Elisabet Viayna Daniel Callejo Raul Ramos Jesús San-Roman-Montero Pablo Barreiro María del Mar Carretero Adam Kolipiski Jesus Canora Antonio Zapatero Michael Chris Runken 《Viruses》2021,13(5)
The global COVID-19 spread has forced countries to implement non-pharmacological interventions (NPI) (i.e., mobility restrictions and testing campaigns) to preserve health systems. Spain is one of the most severely impacted countries, both clinically and economically. In an effort to support policy decision-making, we aimed to assess the impacts of different NPI on COVID-19 epidemiology, healthcare costs and Gross Domestic Product (GDP). A modified Susceptible-Exposed-Infectious-Removed epidemiological model was created to simulate the pandemic evolution. Its output was used to populate an economic model to quantify healthcare costs and GDP variation through a regression model which correlates NPI and GDP change from 42 countries. Thirteen scenarios combining different NPI were consecutively simulated in the epidemiological and economic models. Both increased testing and stringency could reduce cases, hospitalizations and deaths. While policies based on increased testing rates lead to higher healthcare costs, increased stringency is correlated with greater GDP declines, with differences of up to 4.4% points. Increased test sensitivity may lead to a reduction of cases, hospitalizations and deaths and to the implementation of pooling techniques that can increase throughput testing capacity. Alternative strategies to control COVID-19 spread entail differing economic outcomes. Decision-makers may utilize this tool to identify the most suitable strategy considering epidemiological and economic outcomes. 相似文献
995.
Yavuz Mercan Gladys Atim Ahmed E. Kayed M. Ekin Azbazdar Ahmed Kandeil Mohamed A. Ali Adam Rubrum Pamela McKenzie Richard J. Webby Bernard Erima Fred Wabwire-Mangen Qouilazoni A. Ukuli Titus Tugume Denis K. Byarugaba Ghazi Kayali Mariette F. Ducatez Zeynep A. Koer 《Viruses》2021,13(4)
Genetic analysis of circulating avian influenza viruses (AIVs) in wild birds at different geographical regions during the same period could improve our knowledge about virus transmission dynamics in natural hosts, virus evolution as well as zoonotic potential. Here, we report the genetic and molecular characterization of H6N2 influenza viruses isolated from migratory birds in Turkey, Egypt, and Uganda during 2017–2018. The Egyptian and Turkish isolates were genetically closer to each other than they were to the virus isolated from Uganda. Our results also suggest that multiple reassortment events were involved in the genesis of the isolated viruses. All viruses contained molecular markers previously associated with increased replication and/or pathogenicity in mammals. The results of this study indicate that H6N2 viruses carried by migratory birds on the West Asian/East African and Mediterranean/Black Sea flyways have the potential to transmit to mammals including humans. Additionally, adaptation markers in these viruses indicate the potential risk for poultry, which also increases the possibility of human exposure to these viruses. 相似文献
996.
Anne Raben PhD Pia Siig Vestentoft PhD Jennie Brand-Miller PhD Elli Jalo MSc Mathjis Drummen PhD Liz Simpson PhD J. Alfredo Martinez PhD Teodora Handjieva-Darlenska PhD Gareth Stratton PhD Maija Huttunen-Lenz PhD Tony Lam MBA Jouko Sundvall MSc Roslyn Muirhead PhD Sally Poppitt PhD Christian Ritz PhD Kirsi H. Pietiläinen PhD Margriet Westerterp-Plantenga PhD Moira A. Taylor PhD Santiago Navas-Carretero PhD Svetoslav Handjiev PhD Melitta A. McNarry PhD Sylvia Hansen MSc Laura Råman BSc Shannon Brodie MSc Marta P. Silvestre PhD Tanja C. Adam PhD Ian A. Macdonald PhD Rodrigo San-Cristobal PhD Nadka Boyadjieva PhD Kelly A. Mackintosh PhD Wolfgang Schlicht PhD Amy Liu PhD Thomas M. Larsen PhD Mikael Fogelholm DSc 《Diabetes, obesity & metabolism》2021,23(2):324-337
997.
Kohtaro Ooka Harkirat Singh Matthew G. Warndorf Melissa Saul Andrew D. Althouse Anil K. Dasyam Pedram Paragomi Anna Evans Phillips Amer H. Zureikat Kenneth K. Lee Adam Slivka Georgios I. Papachristou Dhiraj Yadav 《Pancreatology》2021,21(1):81-88
Background & aimsThe natural history of groove pancreatitis is incompletely characterized. Published literature suggests a high rate of surgery. We describe the short- and long-term outcomes in a cohort of patients with groove pancreatitis treated at our institution.MethodsMedical records of patients hospitalized in the University of Pittsburgh Medical Center system from 2000 to 2014 and diagnosed with groove pancreatitis based on imaging were retrospectively reviewed. Clinical presentation and outcomes during index admission and follow-up were recorded.ResultsForty-eight patients with groove pancreatitis were identified (mean age 53.2 years, 79% male). Seventy-one percent were alcohol abusers and an equal number were cigarette smokers. Prior histories of acute and chronic pancreatitis were noted in 30 (62.5%) and 21 (43.8%), respectively. Forty-four (91.7%) met criteria for acute pancreatitis during their index admission. Alcohol was the most common etiology (68.8%). No patient experienced organ failure. The most frequent imaging findings were fat stranding in the groove (83.3%), duodenal wall thickening (52.1%), and soft tissue mass/thickening in the groove (50%). Over a mean follow-up of 5.0 years, seven (14.6%) required a pancreas-related surgery. Patients had a high burden of pancreatitis-related readmissions (68.8%, 69.4/100 patient-years). Incident diabetes and chronic pancreatitis were diagnosed in 5 (13.9% of patients at risk) and 8 (29.6% of patients at risk) respectively.ConclusionsGroove pancreatitis has a wide spectrum of severity; most patients have mild disease. These patients have a high burden of readmissions and progression to chronic pancreatitis. A small minority requires surgical intervention. 相似文献
998.
999.
D. Scott Lim MD Robert L. Smith MD Firas Zahr MD Abhijeet Dhoble MD Roger Laham MD Mohamad Lazkani MD Susheel Kodali MD Chad Kliger MD James Hermiller MD Amit Vora MD Ian J. Sarembock MB ChB MD William Gray MD Samir Kapadia MD Adam Greenbaum MD Andrew Rassi MD David Lee MD Adnan Chhatriwalla MD Pinak Shah MD Josep Rodés-Cabau MD Homam Ibrahim MD Lowell Satler MD Howard C. Herrmann MD Paul Mahoney MD Charles Davidson MD George Petrossian MD Mayra Guerrero MD Konstantinos Koulogiannis MD Leo Marcoff MD Linda Gillam MD The CLASP IID Pivotal Trial Investigators 《Catheterization and cardiovascular interventions》2021,98(4):E637-E646
1000.
Aung Myat MD Florence Mouy BMBS Luke Buckner BMBS James Cockburn MD Andreas Baumbach MD Philip MacCarthy PhD Adrian P. Banning MD Nick Curzen PhD Roland Hilling-Smith MD Daniel J. Blackman MD Michael Mullen MD Mark de Belder MD Ian Cox MD Jan Kovac MD Ganesh Manoharan MD Azfar Zaman MD Douglas Muir MBChB David Smith MD Stephen Brecker MD Mark Turner PhD Saib Khogali MD Iqbal S. Malik PhD Osama Alsanjari MRCP Francesca D'Auria PhD Simon Redwood MD Bernard Prendergast DM Uday Trivedi MD Derek Robinson DPhil Peter Ludman MD Adam de Belder MD David Hildick-Smith MD 《Catheterization and cardiovascular interventions》2021,98(3):E444-E452