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Matrix metalloproteinases and atrial remodeling in patients with mitral valve disease and atrial fibrillation 总被引:2,自引:0,他引:2
Anné W Willems R Roskams T Sergeant P Herijgers P Holemans P Ector H Heidbüchel H 《Cardiovascular research》2005,67(4):655-666
BACKGROUND: Atrial fibrillation (AF) is associated with extracellular matrix remodeling involving atrial fibrosis and atrial dilatation. Angiotensin II mediated pathways and matrix metalloproteinases (MMPs) have been implicated in these processes. Our aim was to study atrial structural remodeling and the expression of the angiotensin receptor subtypes and MMPs and their inhibitors (TIMPs) in patients with mitral valve disease with and without AF. METHODS AND RESULTS: Biopsies from right and left atrial appendages (RA and LA) were taken from patients undergoing CABG (n=9, all in sinus rhythm (SR)) or mitral valve surgery (MVS; n=19; 9 with permanent AF and 10 in SR). Patients with MVS and AF had significantly larger atria (versus MVS and SR: p=0.02; versus CABG: p<0.01). The MVS patients had significantly more fibrosis than the control CABG group. Fibrosis was increased in both the AF and SR MVS groups in the LA, but only in the MVS-AF group in the RA. These AF patients had significantly more tricuspid regurgitation than SR patients. MMP-1 was down-regulated in LA of MVS patients (p=0.02) independent of the underlying rhythm (SR or AF; p=0.95). In RA biopsies, MMP-1 was down-regulated only in the MVS and AF group. MMP-9 was down-regulated in the MVS patients compared to CABG both in the RA and LA, and without a difference between the SR and AF groups. Protein expression of AT-1, AT-2, MMP-2, TIMP-1, -2 and -4, TNF-alpha, and TNF-alpha-converting enzyme did not differ significantly between the 3 groups. CONCLUSIONS: Concordant changes between MMP-expression and fibrosis during mitral valve disease, both in LA and RA, suggest involvement of MMPs in structural atrial remodeling. AF itself did not contribute to altered fibrosis or MMP-expression in the LA. The association between AF and RA changes may be precipitated by greater hemodynamic load due to tricuspid regurgitation in these patients. 相似文献
84.
Reginald T. Ho Tania Nanevicz Rupsa Yee Vincent M. Figueredo 《Cardiovascular drugs and therapy / sponsored by the International Society of Cardiovascular Pharmacotherapy》1998,12(3):311-312
Benzocaine-induced methemoglobinemia is a potentially life-threatening complication. We report two cases of methemoglobinemia due to topical benzocaine spray used as premedication for transesophageal echocardiography. A high index of suspicion is needed for this readily treatable condition. 相似文献
85.
William R. Morgenlander Stephanie N. Henson Daniel R. Monaco Athena Chen Kirsten Littlefield Evan M. Bloch Eric Fujimura Ingo Ruczinski Andrew R. Crowley Harini Natarajan Savannah E. Butler Joshua A. Weiner Mamie Z. Li Tania S. Bonny Sarah E. Benner Ashwin Balagopal David Sullivan Shmuel Shoham Thomas C. Quinn Susan H. Eshleman Arturo Casadevall Andrew D. Redd Oliver Laeyendecker Margaret E. Ackerman Andrew Pekosz Stephen J. Elledge Matthew Robinson Aaron A.R. Tobian H. Benjamin Larman 《The Journal of clinical investigation》2021,131(7)
SARS-CoV-2 (CoV2) antibody therapies, including COVID-19 convalescent plasma (CCP), monoclonal antibodies, and hyperimmune globulin, are among the leading treatments for individuals with early COVID-19 infection. The functionality of convalescent plasma varies greatly, but the association of antibody epitope specificities with plasma functionality remains uncharacterized. We assessed antibody functionality and reactivities to peptides across the CoV2 and the 4 endemic human coronavirus (HCoV) genomes in 126 CCP donations. We found strong correlation between plasma functionality and polyclonal antibody targeting of CoV2 spike protein peptides. Antibody reactivity to many HCoV spike peptides also displayed strong correlation with plasma functionality, including pan-coronavirus cross-reactive epitopes located in a conserved region of the fusion peptide. After accounting for antibody cross-reactivity, we identified an association between greater alphacoronavirus NL63 antibody responses and development of highly neutralizing antibodies against CoV2. We also found that plasma preferentially reactive to the CoV2 spike receptor binding domain (RBD), versus the betacoronavirus HKU1 RBD, had higher neutralizing titer. Finally, we developed a 2-peptide serosignature that identifies plasma donations with high anti-spike titer, but that suffer from low neutralizing activity. These results suggest that analysis of coronavirus antibody fine specificities may be useful for selecting desired therapeutics and understanding the complex immune responses elicited by CoV2 infection. 相似文献
86.
Marianna Agudelo Martin Palus Jennifer R. Keeffe Filippo Bianchini Pavel Svoboda Jií Salt Avery Peace Anna Gazumyan Melissa Cipolla Tania Kapoor Francesca Guidetti Kai-Hui Yao Jana Elsterov Dana Teislerov Ale Chrdle Vclav Hnig Thiago Oliveira Anthony P. West Jr. Yu E. Lee Charles M. Rice Margaret R. MacDonald Pamela J. Bjorkman Daniel Rek Davide F. Robbiani Michel C. Nussenzweig 《The Journal of experimental medicine》2021,218(5)
Tick-borne encephalitis virus (TBEV) is an emerging human pathogen that causes potentially fatal disease with no specific treatment. Mouse monoclonal antibodies are protective against TBEV, but little is known about the human antibody response to infection. Here, we report on the human neutralizing antibody response to TBEV in a cohort of infected and vaccinated individuals. Expanded clones of memory B cells expressed closely related anti-envelope domain III (EDIII) antibodies in both groups of volunteers. However, the most potent neutralizing antibodies, with IC50s below 1 ng/ml, were found only in individuals who recovered from natural infection. These antibodies also neutralized other tick-borne flaviviruses, including Langat, louping ill, Omsk hemorrhagic fever, Kyasanur forest disease, and Powassan viruses. Structural analysis revealed a conserved epitope near the lateral ridge of EDIII adjoining the EDI–EDIII hinge region. Prophylactic or early therapeutic antibody administration was effective at low doses in mice that were lethally infected with TBEV. 相似文献
87.
Tania F. Rowley Jonathan P. Kerr Jane E. Willoughby Peter M. W. Johnson Sarah L. Buchan 《European journal of immunology》2013,43(12):3314-3323
Naive T cells require signals from multiple costimulatory receptors to acquire full effector function and differentiate to long‐lived memory cells. The costimulatory receptor, CD27, is essential for optimal T‐cell priming and memory differentiation in a variety of settings, although whether CD27 is similarly required during memory CD8+ T‐cell reactivation remains controversial. We have used OVA and anti‐CD40 to establish a memory CD8+ T‐cell population and report here that their secondary expansion, driven by peptide and anti‐CD40, polyI:C, or LPS, requires CD27. Furthermore, antigenic peptide and a soluble form of the CD27 ligand, CD70 (soluble recombinant CD70 (sCD70)), is sufficient for secondary memory CD8+ T‐cell accumulation at multiple anatomical sites, dependent on CD80/86. Prior to boost, resting effector‐ and central‐memory CD8+ T cells both expressed CD27 with greater expression on central memory cells. Nonetheless, both populations upregulated CD27 after TCR engagement and accumulated in proportion after boosting with Ag and sCD70. Mechanistically, sCD70 increased the frequency of divided and cytolytic memory T cells, conferred resistance to apoptosis and enabled retardation of tumor growth in vivo. These data demonstrate the central role played by CD27/70 during secondary CD8+ T‐cell activation to a peptide Ag, and identify sCD70 as an immunotherapeutic adjuvant for antitumor immunity. 相似文献
88.
Merlin Murilo de Oliveira Heloisa Helena Passos Maria Elizabeth Pereira Momesso Cesar Miguel dos Santos de Oliveira Laiane Cristina Santana Juliana Exel Levada-Pires Adriana C. Hatanaka Elaine Massao-Hirabara Sandro Guaré Renata Cury-Boaventura Maria Fernanda Pithon-Curi Tania C. Gorjão Renata 《Sport Sciences for Health》2021,17(2):431-439
Sport Sciences for Health - Lifestyle and body composition may be simultaneously responsible for immune response modulation. This study aimed to compare plasmatic adipokines concentration and... 相似文献
89.
Francesca Tatini Anna Maria Pugliese Chiara Traini Sandra Niccoli Giovanna Maraula Teresa Ed Dami Benedetta Mannini Tania Scartabelli Felicita Pedata Fiorella Casamenti Fabrizio Chiti 《Neurobiology of aging》2013
Protein misfolded oligomers are thought to be the primary pathogenic species in many protein deposition diseases. Oligomers by the amyloid-β peptide play a central role in Alzheimer's disease pathogenesis, being implicated in synaptic dysfunction. Here we show that the oligomers formed by a protein that has no link with human disease, namely the N-terminal domain of HypF from Escherichia coli (HypF-N), are also synaptotoxic. HypF-N oligomers were found to (i) colocalize with post-synaptic densities in primary rat hippocampal neurons; (ii) induce impairment of long-term potentiation in rat hippocampal slices; and (iii) impair spatial learning of rats in the Morris Water Maze test. By contrast, the native protein and control nontoxic oligomers had none of such effects. These results raise the importance of using HypF-N oligomers as a valid tool to investigate the pathogenesis of Alzheimer's disease, with advantages over other systems for their stability, reproducibility, and costs. The results also suggest that, in the context of a compromised protein homeostasis resulting from aggregation of the amyloid β peptide, a number of oligomeric species sharing common synaptotoxic activity can arise and cooperate in the pathogenesis of the disease. 相似文献
90.
Catherine Bourgeois Tania Lecomte Pierre McDuff Isabelle Daigneault 《Revue canadienne de psychiatrie》2021,66(6):569
Objective:Victims of child sexual abuse (CSA) present with a higher risk of psychotic disorders. However, the developmental course of psychosis following CSA, such as the age at onset, remains unknown. This study aimed to determine whether the age at onset of psychotic disorders was influenced by sexual abuse, sex, and confounding factors (substance misuse, intellectual disability, and socioeconomic status).Method:A prospective matched-cohort design was used, with administrative databases from a child protection agency (CPA) and a public health system. Children who received a substantiated report of CSA at the CPA and whose health data could be retrieved were selected (n = 882) and matched with children from the general population using their date of birth, sex, and geographical area. Survival analysis was performed to estimate the association between sexual abuse, sex, and confounding factors and the age at onset of psychotic disorders.Results:Sexual abuse and substance misuse are significantly associated with the age at onset of psychotic disorders. In the sexually abused group, only substance misuse is associated with the age at onset of psychotic disorders, but this was not significant for the general population.Conclusions:These findings highlight the importance of prevention of psychotic disorders among sexually abused youth, especially those with a substance misuse diagnosis. 相似文献