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101.
An elevated extracellular concentration of D-glucose (i.e. hyperglycaemia) inhibits cell proliferation and incorporation of the endogenous nucleoside thymidine into DNA in human umbilical vein endothelial cells (HUVECs). Cells in their log-phase of growth (3.7 +/- 0.3 days, n = 27) incubated for 30 min with 25 mM D-glucose, but not with equimolar concentrations of L-glucose or D-mannitol, exhibited reduced [3H]thymidine incorporation and cell growth rate, with no change in cell viability (> 98 %), total DNA, protein content or cell volume. Incubation with D-glucose activated protein kinase C (PKC), endothelial NO synthase (eNOS), p42 and p44 mitogen-activated protein kinases (p42/44(mapk)), but inhibited superoxide dismutase (SOD). Incubation with D-glucose also increased cGMP and cAMP levels. The effect of D-glucose was blocked by the PKC inhibitor calphostin C, the MAP kinase kinase 1/2 (MEK1/2) inhibitor PD-98059, the eNOS inhibitor L-NAME, the protein kinase G (PKG) inhibitor KT-5823 and the protein kinase A (PKA) inhibitor KT-5720. In the presence of 5 mM D-glucose, [3H]thymidine incorporation and cell growth were reduced by the PKC activator phorbol 12-myristate 13-acetate (PMA), the NO donor S-nitroso-N-acetyl-L,D-penicillamine (SNAP), dibutyryl cGMP, dibutyryl cAMP and the Ca2+ ionophore A-23187. The effect of A-23187 was blocked by calphostin C and PD-98059. D-Glucose-dependent inhibition of thymidine incorporation and cell proliferation is associated with increased PKC, eNOS, and MEK1/2, but decreased SOD activity, and higher intracellular levels of cGMP, cAMP and Ca2+ in HUVECs. These are cellular mechanisms which may reduce endothelial cell growth in pathological conditions such as in diabetes mellitus or hyperglycaemia. 相似文献
102.
Idia B. Thurston Jessica Curley Sherecce Fields Dimitra Kamboukos Ariz Rojas Vicky Phares 《Journal of community psychology》2008,36(4):411-420
Mental health services are underutilized in our society by both adults and children. This finding presents a potential problem for researchers conducting community‐based research. Previous studies have demonstrated that community‐based researchers frequently do not screen participants for the presence of psychopathology nor do they ascertain whether therapeutic services are currently utilized. The present study explored the prevalence of psychopathology and treatment involvement in a sample of families recruited from the community. Results indicated that a fifth of the participants in this community‐based sample met diagnostic criteria for a psychiatric disorder or were in treatment for psychological difficulties at the time of recruitment for this study. Furthermore, mothers, fathers, and adolescents who met the criteria according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM‐IV; American Psychiatric Association, 1994 ) for a psychological disorder had higher symptomatology than those who did not meet criteria. Methodological suggestions are provided. © 2008 Wiley Periodicals, Inc. 相似文献
103.
We quantified circulating total, rotavirus (RV) and Tetanus toxin (TT) memory B cells (mBc) in healthy adults using a limiting dilution assay (LDA) and a flow cytometry assay (FCA) that permit evaluation of both CD27+ and CD27− mBc.RV mBc were enriched in the CD27−, IgG+ and in the CD27+, IgM+ subsets. The numbers of RV mBc were higher by FCA than by LDA and results of the two assays did not correlate. TT IgGmBc and RV IgA mBc determined by FCA and by LDA correlated with TT plasma IgG and RV plasma IgA, respectively. The mean ratio of specific mBc/μg/ml of the corresponding plasma immunoglobulin was lower for TT IgG than for RV IgA mBc.Our studies contribute to understand the relationship between circulating mBc and serological memory, and enhance our capacity to develop better correlates of protection against RV disease. 相似文献
104.
A role for CD4+CD25+ T cells in regulation of the immune response during human tuberculosis 总被引:12,自引:0,他引:12 下载免费PDF全文
Ribeiro-Rodrigues R Resende Co T Rojas R Toossi Z Dietze R Boom WH Maciel E Hirsch CS 《Clinical and experimental immunology》2006,144(1):25-34
Active tuberculosis (TB) is associated with prolonged suppression of Mycobacterium tuberculosis (MTB)-specific immune responses, but mechanisms involved are understood incompletely. We investigated a potential role for CD4+CD25+ regulatory T cells in depressed anti-MTB immunity by evaluating serially CD4 cell phenotype and interferon (IFN)-gamma production by mononuclear cells from patients with TB. At diagnosis, frequencies of CD4+CD25+ T cells were increased in blood from TB patients compared to healthy purified protein derivative (PPD)-positive controls (with a history of prior TB exposure), and remained elevated at completion of therapy (6 months). By contrast, expression of another activation marker, CD69, by CD4 T cells was increased at diagnosis, but declined rapidly to control levels with treatment. Among CD4+CD25+ T cells from TB patients at diagnosis those expressing high levels of CD25, probably representing regulatory T cells, were increased 2.9-fold when compared to control subjects, while MTB-stimulated IFN-gamma levels in whole blood supernatants were depressed. A role for CD4+CD25+ T cells in depressed IFN-gamma production during TB was substantiated in depletion experiments, where CD25+-depleted CD4 T cells produced increased amounts of IFN-gamma upon MTB stimulation compared to unseparated T cells. At follow-up, IFN-gamma production improved most significantly in blood from TB patients with high baseline frequencies of CD4+CD25+ T cells (more than threefold higher than controls for both total and CD25hi+ CD4 T cells), who also had a significant drop in frequencies of both total and 'regulatory' CD4+CD25+ T cells in response to treatment. Expansion of CD4+CD25+ regulatory T cells during active TB may play a role in depressed T cell IFN-gamma production. 相似文献
105.
Irina Buckle Anthony Johnson Ingrid Leal Rojas Vicky Weinert David P. Sester Kristen Radford Camille Guillerey 《European journal of immunology》2023,53(6):2250118
Growing interest surrounds adoptive cellular therapies utilizing Natural Killer (NK) cells, which can be obtained from various sources, including umbilical cord blood (UCB) and adult peripheral blood (APB). Understanding NK cell receptor expression and diversity in such cellular sources will guide future therapeutic designs. We used a 20-color flow cytometry panel to compare unstimulated and cytokine-activated UCB and APB NK cells. Our analysis showed that UCB NK cells express slightly higher levels of the immune checkpoints PD-1, TIGIT, and CD96 compared to their APB counterparts. Unsupervised hierarchical clustering and dimensionality reduction analyses revealed enrichment in CD56neg as well as mature NKp46neg and CD56+CD16+ NK cell populations in UCB whereas CD57+ terminally differentiated NK cells with variable expression of KIRs and CD16 were found in APB. These populations were conserved following stimulation with IL-12, IL-15, and IL-18. Cytokine stimulation was associated with the downregulation of TIGIT and CD16 on multiple NK cell subsets in UCB and APB. Among UCB CD16− NK cell populations, TIGIT+ NK cells produced more IFN-γ than their TIGIT− counterparts. Our data demonstrate higher immune checkpoint expression on UCB NK cells compared to APB. However, the expression of TIGIT immune checkpoint is not indicative of NK cell exhaustion. 相似文献
106.
Sonia Moreno-Grau Itziar de Rojas Isabel Hernández Inés Quintela Laura Montrreal Montserrat Alegret Begoña Hernández-Olasagarre Laura Madrid Antonio González-Perez Olalla Maroñas Maitée Rosende-Roca Ana Mauleón Liliana Vargas Asunción Lafuente Carla Abdelnour Octavio Rodríguez-Gómez Silvia Gil Miguel Ángel Santos-Santos Agustín Ruiz 《Alzheimer's & dementia》2019,15(10):1333-1347
IntroductionLarge variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways.MethodsGenome Research at Fundacio ACE ([email protected]) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, [email protected] series were meta-analyzed with additional genome-wide association study data sets.ResultsWe classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444.DiscussionThe regulation of vasculature is a prominent causal component of probable AD. [email protected] meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series. 相似文献
107.
Elevated cerebroside antibody levels in human visceral and cutaneous leishmaniasis, Trypanosoma rangeli infection, and chronic Chagas' disease 总被引:2,自引:0,他引:2
A natural cerebroside (antiC) IgM antibody was found at relatively high levels in the serum of every healthy individual studied. The reactivity of the antibody was assessed by using highly purified bovine brain galactocerebroside (galC) or human glucocerebroside (gluC) as antigen. The importance of fatty acid moiety of galC in antigen-antibody reaction was demonstrated by low immunoreactivity using 1-beta-D-galactosyl sphingosine (GS) as antigen and by the absence of absorption to GS-bearing liposomes. The presence of alpha-hydroxy and non-hydroxy fatty acids in galC did not modify its immunoreactivity. Cerebroside antibody binding activity was only partially blocked by 0.5 M galactose or alpha- and beta-methylgalactopyranoside, suggesting poor specificity of antiC for a specific glycosidic residue or linkage. In fact, liposome-bearing gluC absorbed galC. AntiC did not adsorb on rabbit, guinea pig, or human erythrocytes (RBC), but absorbed strongly on rat RBC. Elevated antibody levels were found in 57% of Kala azar patients, 56% of Trypanosoma rangeli-infected patients, 30% of chronic chagasic patients, and 20% of cutaneous leishmaniasis patients, but were not found in 16 other inflammatory or infectious diseases studied. This suggests an association between Kinetoplastida infection and elevated levels of antiC, with parasitic galC acting probably as a highly immunogenic antigen. A possible role of anti-galC in the neuropathological symptoms of Chagas' disease and in the control of parasitemia levels in T. rangeli-infected individuals is discussed. 相似文献
108.
Rojas Juan I. Henestroza Paula Giachello Susana Patrucco Liliana Cristiano Edgardo Carnero Contentti Edgar 《Journal of neurovirology》2021,27(5):750-754
Journal of NeuroVirology - The objective of the present study was to identify the frequency of MS patients in Latin America (LATAM) that received the influenza vaccine during the most recent season... 相似文献
109.
Pablo Galeano Juan Ignacio Romero María Jesús Luque‐Rojas Juan Suárez Mariana Inés Holubiec Verónica Bisagno Luis Javier Santín Fernando Rodríguez De Fonseca Francisco Capani Eduardo Blanco 《Synapse (New York, N.Y.)》2013,67(9):553-567
Perinatal asphyxia (PA) increases the likelihood of suffering from dopamine‐related disorders, such as ADHD and schizophrenia. Since dopaminergic transmission plays a major role in cocaine sensitization, the purpose of this study was to determine whether PA could be associated with altered behavioral sensitization to cocaine. To this end, adult rats born vaginally (CTL), by caesarean section (C+), or by C+ with 15 min (PA15, moderate PA) or 19 min (PA19, severe PA) of global anoxia were repeatedly administered with cocaine (i.p., 15 mg/kg) and then challenged with cocaine (i.p., 15 mg/kg) after a 5‐day withdrawal period. In addition, c‐Fos, FosB/ΔFosB, DAT, and TH expression were assessed in dorsal (CPu) and ventral (NAcc) striatum. Results indicated that PA15 rats exhibited an increased locomotor sensitization to cocaine, while PA19 rats displayed an abnormal acquisition of locomotor sensitization and did not express a sensitized response to cocaine. c‐Fos expression in NAcc, but not in CPu, was associated with these alterations in cocaine sensitization. FosB/ΔFosB expression was increased in all groups and regions after repeated cocaine administration, although it reached lower expression levels in PA19 rats. In CTL, C+, and PA15, but not in PA19 rats, the expression of TH in NAcc was reduced in groups repeatedly treated with cocaine, independently of the challenge test. Furthermore, this reduction was more pronounced in PA15 rats. DAT expression remained unaltered in all groups and regions studied. These results suggest that moderate PA may increase the vulnerability to drug abuse and in particular to cocaine addiction. Synapse 67:553–567, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
110.
F. M. González Valverde F. Mauri Barberá M. Molto Aguado N. Torregrosa A. Hernández Quiles F. Menárguez Pina M. J. Gómez Ramos M. García Real J. A. Barreras Mateos J. L. Vázquez Rojas 《European Surgery》2004,36(4):253-256
Summary BACKGROUND: Endometriosis is a relatively common pathology in women of childbearing age and of low parity but rarely shows
extraperitoneal involvement. The main aim of this paper is to raise the attention of specialists to the necessity of carrying
out penetrating diagnosis of nonspecific extraperitoneal masses occurring in women of reproductive age. METHODS: We performed
a retrospective review of six patients diagnosed with extraperitoneal endometriosis who were treated at the Vega Baja University
Hospital (Spain) during the last 5 years. RESULTS: Surgical treatment had positive results in five patients. The preoperative
diagnosis was correctly made in only two patients. The accurate aetiology of endometriosis remains unknown and diagnosis is
based on clinical and cytopathological findings. CONCLUSIONS: Surgical treatment of extraperitoneal endometriosis is recommended.
However, postoperative follow-up is obligatory and hormonal suppressive therapy may be necessary. Medical treatment with gestagens,
Danazol, or agonists of the gonadotropin-releasing hormone are ineffective in endometriomas which are bigger than 2 cm.
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