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Agarwal Amol Maheshwari Anurag Verma Sandeep Arrup Denise Phillips Laila Vinayek Rakesh Nair Padmanabhan Hagan Matilda Dutta Sudhir 《Digestive diseases and sciences》2021,66(6):2000-2004
Digestive Diseases and Sciences - To compare the clinical outcomes of different protocols for fecal microbiota transplantation (FMT) in two community hospitals with similar patient demographics.... 相似文献
153.
Derkatch IL Uptain SM Outeiro TF Krishnan R Lindquist SL Liebman SW 《Proceedings of the National Academy of Sciences of the United States of America》2004,101(35):12934-12939
Prions are infectious protein conformations that are generally ordered protein aggregates. In the absence of prions, newly synthesized molecules of these same proteins usually maintain a conventional soluble conformation. However, prions occasionally arise even without a homologous prion template. The conformational switch that results in the de novo appearance of yeast prions with glutamine/aspargine (Q/N)-rich prion domains (e.g., [PSI+]), is promoted by heterologous prions with a similar domain (e.g., [RNQ+], also known as [PIN+]), or by overexpression of proteins with prion-like Q-, N-, or Q/N-rich domains. This finding led to the hypothesis that aggregates of heterologous proteins provide an imperfect template on which the new prion is seeded. Indeed, we show that newly forming Sup35 and preexisting Rnq1 aggregates always colocalize when [PSI+] appearance is facilitated by the [RNQ+] prion, and that Rnq1 fibers enhance the in vitro formation of fibers by the prion domain of Sup35 (NM). The proteins do not however form mixed, interdigitated aggregates. We also demonstrate that aggregating variants of the polyQ-containing domain of huntingtin promote the de novo conversion of Sup35 into [PSI+]; whereas nonaggregating variants of huntingtin and aggregates of non-polyQ amyloidogenic proteins, transthyretin, alpha-synuclein, and synphilin do not. Furthermore, transthyretin and alpha-synuclein amyloids do not facilitate NM aggregation in vitro, even though in [PSI+] cells NM and transthyretin aggregates also occasionally colocalize. Our data, especially the in vitro reproduction of the highly specific heterologous seeding effect, provide strong support for the hypothesis of cross-seeding in the spontaneous initiation of prion states. 相似文献
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Sudarshi S Stümpfle R Armstrong M Ellman T Parton S Krishnan P Chiodini PL Whitty CJ 《Tropical medicine & international health : TM & IH》2003,8(8):728-732
OBJECTIVES: To assess whether the clinical and laboratory methods for diagnosing Strongyloides stercoralis infection in non-endemic countries is different between those who are chronically exposed and those who travel. METHODS: Analysis of laboratory and clinical data from 204 patients having S. stercoralis infection at the Hospital for Tropical Diseases, London. RESULTS: Sixty-four travellers and 128 immigrants from endemic countries had laboratory-proven strongyloides. In those with microscopically proven disease, serology was 73% sensitive in travellers and 98% sensitive in immigrants (P < 0.001). There was no difference in the eosinophil count between the two groups with 19% having a normal count. Patterns of symptoms varied between the groups, and around one-third were asymptomatic in both groups. Serology was of limited use in follow-up. CONCLUSIONS: Eosinophil count and stool microscopy are insufficiently sensitive to be used alone for screening strongyloides. The sensitivity of serology is good in immigrants with chronic infection, but lower in travellers. 相似文献
155.
Wnt8a and Wnt3a cooperate in the axial stem cell niche to promote mammalian body axis extension 下载免费PDF全文
Thomas J. Cunningham Sandeep Kumar Terry P. Yamaguchi Gregg Duester 《Developmental dynamics》2015,244(6):797-807
Background: Vertebrate body axis extension occurs in a head‐to‐tail direction from a caudal progenitor zone that responds to interacting signals. Wnt/β‐catenin signaling is critical for generation of paraxial mesoderm, somite formation, and maintenance of the axial stem cell pool. Body axis extension requires Wnt8a in lower vertebrates, but in mammals Wnt3a is required, although the anterior trunk develops in the absence of Wnt3a. Results: We examined mouse Wnt8a–/– and Wnt3a–/– single and double mutants to explore whether mammalian Wnt8a contributes to body axis extension and to determine whether a posterior growth function for Wnt8a is conserved throughout the vertebrate lineage. We find that caudal Wnt8a is expressed only during early somite stages and is required for normal development of the anterior trunk in the absence of Wnt3a. During this time, we show that Wnt8a and Wnt3a cooperate to maintain Fgf8 expression and prevent premature Sox2 up‐regulation in the axial stem cell niche, critical for posterior growth. Similar to Fgf8, Wnt8a requires retinoic acid (RA) signaling to restrict its caudal expression boundary and possesses an upstream RA response element that binds RA receptors. Conclusions: These findings provide new insight into interaction of caudal Wnt‐FGF‐RA signals required for body axis extension. Developmental Dynamics 244:797–807, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
156.
Absence of late gadolinium enhancement on cardiac magnetic resonance imaging in ventricular fibrillation and nonischemic cardiomyopathy 下载免费PDF全文
Aleksandr Voskoboinik MBBS Michael C. G. Wong MBBS Jessica K. Elliott MBBS BMedSc Benedict T. Costello MBBS Sandeep Prabhu MBBS Justin A. Mariani MBBS PhD Jonathan M. Kalman MBBS PhD Peter M. Kistler MBBS PhD Andrew J. Taylor MBBS PhD Joseph B. Morton MBBS PhD 《Pacing and clinical electrophysiology : PACE》2018,41(9):1109-1115
Introduction
Cardiac magnetic resonance (CMR)‐identified late gadolinium enhancement (LGE), representing regional fibrosis, is often used to predict ventricular arrhythmia risk in nonischemic cardiomyopathy (NICM). However, LGE is more closely correlated with sustained monomorphic ventricular tachycardia (SMVT) than ventricular fibrillation (VF). We characterized CMR findings of ventricular LGE in VF survivors.Methods
We examined consecutively resuscitated VF survivors undergoing contrast‐enhanced 1.5T CMR between 9/2007 and 7/2016. We excluded coronary artery disease, hypertrophic cardiomyopathy, amyloid, sarcoid, arrhythmogenic right ventricular cardiomyopathy, and channelopathy. Preexisting implantable cardioverter‐defibrillator (ICD) was a CMR contraindication. VF patients were divided into three groups: (1) NICM, (2) left ventricular (LV) dilatation with normal LV ejection fraction (LVEF), and (3) normal LV size and LVEF. Two groups of NICM patients with and without SMVT were examined for comparison.Results
We analyzed 87 VF patients, and found that LGE was seen in 8/22 (36%) with NICM (LVEF 38 ± 11%, LV end‐diastolic volume index [LVEDVI] 134 ± 68 mL/BSA), 11/40 (28%) with LV dilatation and normal LVEF (LVEDVI 103 ± 17 mL/BSA), 4/25 (16%) with normal LV size and LVEF. Incidence of LGE in NICM patients without prior ventricular tachycardia/VF (LVEF 36 ± 12%, LVEDVI 141 ± 46 mL/body surface area [BSA]) was 117/277 and was not lower than those with VF and NICM (42% vs 36%; P = 0.59). By contrast, 22/37 NICM patients with SMVT (LVEF 42 ± 11%, LVEDVI 123 ± 48 mL/BSA) were LGE‐positive (59% NICM‐SMVT vs 36% NICM‐VF; P = 0.04).Conclusion
Most VF survivors with a diagnosis of NICM did not have LGE on CMR and would not have met primary prevention ICD criteria based on LVEF. Absence of LGE may not portend a benign prognosis in NICM. Novel strategies for determining SCD risk in this cohort are required.157.
Oral anticoagulation and left atrial thrombi resolution in nonrheumatic atrial fibrillation or flutter: A systematic review and meta‐analysis 下载免费PDF全文
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Ian J Douglas Krishnan Bhaskaran Rachel L Batterham Liam Smeeth 《British journal of clinical pharmacology》2015,79(6):1020-1027