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61.
Alberto Bedogni Stefano Fedele Giorgio Bedogni Matteo Scoletta Gianfranco Favia Giuseppe Colella Alessandro Agrillo Giordana Bettini Olga Di Fede Giacomo Oteri Vittorio Fusco Mario Gabriele Livia Ottolenghi Stefano Valsecchi Stephen Porter Massimo Petruzzi Paolo Arduino Salvatore D’Amato Claudio Ungari Pok-Lam Fung Polly Giorgia Saia Giuseppina Campisi 《The British journal of oral & maxillofacial surgery》2014
Management of osteonecrosis of the jaw associated with antiresorptive agents is challenging, and outcomes are unpredictable. The severity of disease is the main guide to management, and can help to predict prognosis. Most available staging systems for osteonecrosis, including the widely-used American Association of Oral and Maxillofacial Surgeons (AAOMS) system, classify severity on the basis of clinical and radiographic findings. However, clinical inspection and radiography are limited in their ability to identify the extent of necrotic bone disease compared with computed tomography (CT). We have organised a large multicentre retrospective study (known as MISSION) to investigate the agreement between the AAOMS staging system and the extent of osteonecrosis of the jaw (focal compared with diffuse involvement of bone) as detected on CT. We studied 799 patients with detailed clinical phenotyping who had CT images taken. Features of diffuse bone disease were identified on CT within all AAOMS stages (20%, 8%, 48%, and 24% of patients in stages 0, 1, 2, and 3, respectively). Of the patients classified as stage 0, 110/192 (57%) had diffuse disease on CT, and about 1 in 3 with CT evidence of diffuse bone disease was misclassified by the AAOMS system as having stages 0 and 1 osteonecrosis. In addition, more than a third of patients with AAOMS stage 2 (142/405, 35%) had focal bone disease on CT. We conclude that the AAOMS staging system does not correctly identify the extent of bony disease in patients with osteonecrosis of the jaw. 相似文献
62.
Livia Picchi COMAR Beatriz Martines de SOUZA Larissa Tercilia GRIZZO Marília Afonso Rabelo BUZALAF Ana Carolina MAGALH?ES 《Journal of applied oral science : revista FOB》2014,22(2):138-143
Fluoride varnishes play an important role in the prevention of dental caries,
promoting the inhibition of demineralization and the increase of
remineralization.
Objective
This study aimed to analyze the amount of fluoride released into water and artificial saliva from experimental TiF4 and NaF varnishes, with different concentrations, for 12 h.Material and Methods
Fluoride varnishes were applied on acrylic blocks and then immersed in 10 ml of deionized water and artificial saliva in polystyrene bottles. The acrylic blocks were divided in seven groups (n=10): 1.55% TiF4 varnish (0.95% F, pH 1.0); 3.10% TiF4 varnish (1.90% F, pH 1.0); 3.10% and 4% TiF4 varnish (2.45% F, pH 1.0); 2.10% NaF varnish (0.95% F, pH 5.0); 4.20% NaF varnish (1.90% F, pH 5.0); 5.42% NaF varnish (2.45% F, pH 5.0) and control (no treatment, n=5). The fluoride release was analyzed after 1/2, 1, 3, 6, 9 and 12 h of exposure. The analysis was performed using an ion-specific electrode coupled to a potentiometer. Two-way ANOVA and Bonferroni''s test were applied for the statistical analysis (p<0.05).Results
TiF4 varnishes released larger amounts of fluoride than NaF varnishes during the first 1/2 h, regardless of their concentration; 4% TiF4 varnish released more fluoride than NaF varnishes for the first 6 h. The peak of fluoride release occurred at 3 h. There was a better dose-response relationship among the varnishes exposed to water than to artificial saliva.Conclusions
The 3.10% and 4% TiF4 -based varnishes have greater ability to release fluoride into water and artificial saliva compared to NaF varnish; however, more studies must be conducted to elucidate the mechanism of action of TiF4 varnish on tooth surface. 相似文献63.
Giovanne B. Diniz Daniella S. Battagello Marianne O. Klein Bianca S. M. Bono Jozélia G. P. Ferreira Livia C. Motta-Teixeira Jessica C. G. Duarte Françoise Presse Jean-Louis Nahon Antoine Adamantidis Melissa J. Chee Luciane V. Sita Jackson C. Bittencourt 《Journal of neuroscience research》2020,98(10):2045-2071
Melanin-concentrating hormone (MCH) is a ubiquitous vertebrate neuropeptide predominantly synthesized by neurons of the diencephalon that can act through two G protein-coupled receptors, called MCHR1 and MCHR2. The expression of Mchr1 has been investigated in both rats and mice, but its synthesis remains poorly described. After identifying an antibody that detects MCHR1 with high specificity, we employed immunohistochemistry to map the distribution of MCHR1 in the CNS of rats and mice. Multiple neurochemical markers were also employed to characterize some of the neuronal populations that synthesize MCHR1. Our results show that MCHR1 is abundantly found in a subcellular structure called the primary cilium, which has been associated, among other functions, with the detection of free neurochemical messengers present in the extracellular space. Ciliary MCHR1 was found in a wide range of areas, including the olfactory bulb, cortical mantle, striatum, hippocampal formation, amygdala, midline thalamic nuclei, periventricular hypothalamic nuclei, midbrain areas, and in the spinal cord. No differences were observed between male and female mice, and interspecies differences were found in the caudate-putamen nucleus and the subgranular zone. Ciliary MCHR1 was found in close association with several neurochemical markers, including tyrosine hydroxylase, calretinin, kisspeptin, estrogen receptor, oxytocin, vasopressin, and corticotropin-releasing factor. Given the role of neuronal primary cilia in sensing free neurochemical messengers in the extracellular fluid, the widespread distribution of ciliary MCHR1, and the diverse neurochemical populations who synthesize MCHR1, our data indicate that nonsynaptic communication plays a prominent role in the normal function of the MCH system. 相似文献
64.
Elena Andreucci Anna Laurenzana Silvia Peppicelli Alessio Biagioni Francesca Margheri Jessica Ruzzolini Francesca Bianchini Gabriella Fibbi Mario Del Rosso Chiara Nediani Simona Serratì Livia Fucci Michele Guida Lido Calorini 《Oncology research》2020,28(9):873-884
Malignant melanoma is a highly aggressive skin cancer characterized by an elevated grade of tumor cell plasticity. Such plasticity allows adaptation of melanoma cells to different hostile conditions and guarantees tumor
survival and disease progression, including aggressive features such as drug resistance. Indeed, almost 50% of
melanoma rapidly develop resistance to the BRAFV600E inhibitor vemurafenib, with fast tumor dissemination,
a devastating consequence for patients’ outcomes. Vasculogenic mimicry (VM), the ability of cancer cells to
organize themselves in perfused vascular-like channels, might sustain tumor spread by providing vemurafenibresistant cancer cells with supplementary ways to enter into circulation and disseminate. Thus, this research
aims to determine if vemurafenib resistance goes with the acquisition of VM ability by aggressive melanoma
cells, and identify a driving molecule for both vemurafenib resistance and VM. We used two independent
experimental models of drug-resistant melanoma cells, the first one represented by a chronic adaptation of
melanoma cells to extracellular acidosis, known to drive a particularly aggressive and vemurafenib-resistant
phenotype, the second one generated with chronic vemurafenib exposure. By performing in vitro tube formation assay and evaluating the expression levels of the VM markers EphA2 and VE-cadherin by Western blotting
and flow cytometer analyses, we demonstrated that vemurafenib-resistant cells obtained by both models are
characterized by an increased ability to perform VM. Moreover, by exploiting the CRISPR-Cas9 technique and
using the urokinase plasminogen activator receptor (uPAR) inhibitor M25, we identified uPAR as a driver of
VM expressed by vemurafenib-resistant melanoma cells. Thus, uPAR targeting may be successfully leveraged
as a new complementary therapy to inhibit VM in drug-resistant melanoma patients, to counteract the rapid
progression and dissemination of the disease. 相似文献
65.
66.
67.
Vinicius M. Mello Lucas M. Bianchi Paulo Sergio F. Sousa Pedro S. Tavares Daniel R. G. Di Salvo Cleber F. Ginuino Nathalia A. A. Almeida Carlos A. S. Fernandes Francisco C. A. Mello Livia M. Villar Lia L. Lewis-Ximenez Barbara V. Lago 《Viruses》2022,14(2)
This study aims to evaluate the epidemiological and molecular features associated with HAV transmission in adults in Rio de Janeiro during a period of increased registered cases of HAV (2017–2018). Socio-epidemiological data and serum samples from anti-HAV IgM+ individuals were obtained. HAV RNA was RT-PCR amplified and sequenced for further phylogenetic and phylogeographic analyses. From fifty-two HAV IgM+ individuals, most were men (78.85%; p = 0.024), aged 20–30 years old (84.61%; p < 0.001), resided in the Rio de Janeiro north zone (31/52; 59.62%; p = 0.001), and are men who have sex with men (MSM) (57.69%; p = 0.002). Sexual practices were more frequent (96%) than others risk factors (food-borne (44%), water-borne (42.31%), and parenteral (34.62%)). Individuals who traveled to endemic regions had a 7.19-fold (1.93–36.04; p < 0.01) increased risk of HAV. Phylogenetic analysis revealed four distinct clades of subgenotype IA, three of them comprised sequences from European/Asian MSM outbreaks and one from Brazilian endemic strains. Bayesian Inference showed that the imported strains were introduced to Brazil during large mass sportive events. Sexual orientation and sexual practices may play a role in acquiring HAV infection. Public policies targeting key populations must be implemented to prevent further dissemination of HAV and other STIs. 相似文献
68.
Sönke Harder Rainer Podschun Livia Grancicova Christian Mehl Matthias Kern 《Clinical oral investigations》2013,17(4):1135-1142
Objective
Information about the spectrum of microorganisms in the intraimplant cavities of two-piece dental implants is scarce. The purpose of this study was to assess the intraimplant microflora of two-piece dental implants by conventional biochemical testing, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), and 16 s rDNA gene sequencing.Materials and methods
Ten patients (six men and four women; average age?=?66.7 years; age range?=?58–78 years) received 35 two-piece titanium implants carrying ball attachments. Biofilm sampling was performed with sterile microbrushes, and nonadherent microbial samples were obtained by injection and reuptake of predefined volumes of NaCl solution. The samples were cultured and analyzed by conventional biochemical testing, MALDI-TOF MS, and 16 s rDNA gene sequencing.Results
Of the 103 species detected, 27 and 33 were identified only in the biofilm and nonadherent microbial samples, respectively. Forty-three species were identified in both types of samples.Conclusions
Two-piece dental implants harbored a broad spectrum of gram-positive and gram-negative aerobes and anaerobes, especially rods and cocci.Clinical relevance
These findings confirm bacterial translocation from the oral cavity to intraimplant cavities. Microbiological methods as used in this study are necessary to reveal the complete vital microflora of intraimplant cavities. 相似文献69.
70.
Ticala Maria Tirinescu Dacian Călin Rusu Crina Claudia Moldovan Diana Potra Alina Ramona Coman Anca Laura Bondor Cosmina Ioana Budisan Livia Kacsó Ina Maria 《International urology and nephrology》2019,51(6):1035-1042
International Urology and Nephrology - It has been suggested that advanced glycation end products (AGEs) are involved in atherogenesis, vascular calcification and remodeling, including neointimal... 相似文献