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Ferraris ME Samar ME Busso C Avila RE Ferraris RV de Fabro SP 《Acta odontológica latinoamericana : AOL》1993,7(1):23-29
The histogenesis of the salivary glands was structurally and cytochemically studied in human embryos and fetuses during the period of 8 to 32 weeks of intrauterine life. Glandular buds appeared at about 12 weeks of embryonic development. The rounded distal ends of the epithelial cords and neighbouring mesenchyma showed small and abundant PAS positive and alcianophilic granules. At age 14 weeks the secretory end pieces and the duct system were seen at different morphologic and structural stages of a differentiation. Mucous acini with scanty mixed acini predominated and serous acini appeared occasionally. From 20 to 24 weeks the mucous acini stained with toluidine blue featured different degrees of metachromasia even in the case of cells of the same acinus. In the ducts it was also possible to identify metachromatic cells intermingled with basophilic cells in the epithelial coat. These findings suggest that the palatine glands present typical histophysiological material from 14 to 20 weeks. The presence of PAS positive, alcianophilic and metachromatic secretory substance in the acinar lumen and the luminal content of ducts suggests that mucin secretion begins during intrauterine life. 相似文献
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Gustavo Adolfo Avila Montes Mercedes Martínez Catalina Sherman Eduardo Fernández Cerna 《Pan American journal of public health》2004,16(2):84-94
OBJECTIVE: To evaluate the effectiveness of a special course on environmental health and dengue, given to primary school students and intended to promote behavioral changes in the mothers of those students that would lead to the safe handling of water, adequate disposal of trash, and control of household breeding sites of Aedes aegypti, the mosquito vector for dengue. METHODS: In the period from April to November 2002 a community field trial was carried out that included four public schools in the city of Comayaguela, Honduras. Two of the schools formed the intervention group, and the two others made up the comparison or control group. The data collection activities before and after the intervention included knowledge tests for the schoolchildren and the teachers; surveys of the knowledge, attitudes, and practices of the students' mothers; entomological surveys (systematic checking in order to find water containers, to search for mosquito larvae) in the homes of the schoolchildren; in-depth interviews with the students' mothers; observation in the classrooms; and postintervention focus group with the teachers. RESULTS: During the intervention period the largest epidemic of classical dengue ever in the history of Tegucigalpa, the capital of Honduras, occurred. That event prompted the Secretariat of Health to undertake large-scale control activities. In the two intervention schools there was a significant increase in the students' knowledge of the following three variables: dengue caused by a virus, life cycle of the vector, and reduction of breeding sites, which is the most effective measure for controlling the vector (P < 0.0001 for all those increases in knowledge). There were also significant increases in the knowledge of the same variables among the teachers in the intervention schools: dengue caused by a virus (P = 0.03), life cycle of the vector (P = 0.01), and reduction of breeding sites (P = 0.004). Reducing the number of breeding sites as being the best measure for controlling Aedes aegypti was the knowledge variable that showed the greatest change among the mothers in the intervention group (P = 0.02). The values for two of the entomological indices (the House index and the Breteau index) were better in the intervention group than in the control group, but the difference was not statistically significant. However, there was a statistically significant difference in the Breteau index values between the two control group schools and the one intervention school where the education course was implemented more adequately than in the other intervention school. CONCLUSIONS: The application of educational interventions directed to schoolchildren, as a part of a comprehensive plan for controlling Aedes aegypti, is an effective way to raise the awareness of teachers and parents with respect to the problem of dengue, and it also helps in encouraging family members to be involved in reducing breeding sites in the home. In moving to control the dengue vector, this strategy should take into consideration the involvement not only of families but also of civic and public institutions in the community. Given our results, it appears that this approach of using a special course for schoolchildren can constitute a fundamental pillar in the strategy for integrated dengue control. 相似文献
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Obsessive-compulsive spectrum disorders have emerged as a differentiated entity, characterized with intrusive and obsessive thoughts or repetitive behaviors whose major syndrome would be the classical obsessive-compulsive disorder. In order to spread this concept among neurologists, we present three cases that can be considered as obsessive-compulsive spectrum disorders, in which structural cerebral lesions co-exist. Obsessive-compulsive spectrum disorders share with obsessive-compulsive disorder several clinical and neurobiological characteristics as well as their therapeutic response. Nevertheless, obsessive-compulsive spectrum disorders have a lesser positive familial history incidence and a later start than obsessive-compulsive disorder. Recent neurobiological studies using functional and structural neuroimaging in patients with obsessive-compulsive disorder together with neuropsychological studies reveal the existence of defects in the following neural circuits: frontal-orbital-basal ganglia-thalamus-cortical and their limbic connections. In a similar manner as it occurs with obsessive-compulsive disorder, research on obsessive-compulsive spectrum disorders will provide the pathophysiological basis of the obsessive-compulsive disorder in the dysfunctionality of the previously mentioned neurological circuits. 相似文献
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Rhanderson Cardoso Gustavo B. Justino Fabrissio P. Graffunder Leticia Benevides Leonardo Knijnik Luana M.F. Sanchez Andre dAvila 《Arquivos brasileiros de cardiologia》2022,119(1):87
BackgroundCatheter ablation is a well-established therapy for rhythm control in patients who are refractory or intolerant to anti-arrhythmic drugs (AAD). Less is known about the efficacy of catheter ablation compared with AAD as a first-line strategy for rhythm control in atrial fibrillation (AF).ObjectivesWe aimed to perform a systematic review and meta-analysis of catheter ablation vs. AAD in patients naïve to prior rhythm control therapies.MethodsPubMed, EMBASE, and Cochrane databases were searched for randomized controlled trials that compared catheter ablation to AAD for initial rhythm control in symptomatic AF and reported the outcomes of (1) recurrent atrial tachyarrhythmias (ATs); (2) symptomatic AF; (3) hospitalizations; and (4) symptomatic bradycardia. Heterogeneity was examined with I2statistics. P values of < 0.05 were considered statistically significant.ResultsWe included five trials with 994 patients, of whom 502 (50.5%) underwent catheter ablation. Mean follow-up ranged from one to five years. Recurrences of AT (OR 0.36; 95% CI 0.25-0.52; p<0.001) and symptomatic AF (OR 0.32; 95% CI 0.18-0.57; p<0.001), and hospitalizations (OR 0.25; 95% CI 0.15-0.42; p<0.001) were significantly less frequent in patients treated with catheter ablation compared with AAD. Symptomatic bradycardia was not significantly different between groups (OR 0.55; 95% CI 0.18-1.65; p=0.28). Significant pericardial effusions or tamponade occurred in eight of 464 (1.7%) patients in the catheter ablation group.ConclusionThese findings suggest that catheter ablation has superior efficacy to AAD as an initial rhythm control strategy in patients with symptomatic AF. 相似文献
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Romero R Espinoza J Hassan S Gotsch F Kusanovic JP Avila C Erez O Edwin S Schmidt AM 《Journal of perinatal medicine》2008,36(5):388-398
Abstract Objective: The receptor for advanced glycation end products (RAGE) has been proposed to participate in the innate and adaptive immune responses. RAGE can induce production of pro-inflammatory cytokines and chemokines, as well as neutrophil chemotaxis in a manner that may be suppressed or stimulated by soluble, truncated forms of RAGE including the soluble form of RAGE (sRAGE) and endogenous secretory RAGE (esRAGE). The objective of this study was to determine whether intra-amniotic infection/inflammation (IAI) is associated with changes in the amniotic fluid concentration of sRAGE and esRAGE. Study design: Amniotic fluid (AF) was retrieved from patients in the following groups: 1) mid-trimester (14-18 weeks of gestation; n=68); 2) term not in labor (n=24); 3) term in labor (n=51); 4) preterm labor and intact membranes (n=124); and 5) preterm PROM (n=80). Intra-amniotic infection and inflammation were defined as the presence of a positive amniotic fluid culture for microorganisms and an AF interleukin-6 concentration >/=2.6 ng/mL, respectively. The AF concentration of sRAGE and esRAGE were determined using specific and sensitive ELISAs which measured total immunoreactive sRAGE and esRAGE, respectively. Patients were matched for gestational age at amniocentesis to compare the AF concentration of sRAGE and esRAGE in patients with and without IAI. Non-parametric statistics were used for analysis and a P<0.05 was considered significant. Results: 1) Patients at term not in labor had higher median AF concentrations of sRAGE and esRAGE than those in the mid-trimester (P<0.001 for both comparisons) and those at term in labor (P=0.03 and P=0.04, respectively); 2) patients with preterm labor and intact membranes with intra-amniotic infection/inflammation (IAI) had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.02 and P=0.005, respectively); 3) similarly, patients with preterm PROM with IAI had higher median AF concentrations of sRAGE and esRAGE than those without IAI (P=0.03 and P=0.02, respectively). Conclusion: Intra-amniotic infection/inflammation is associated with increased amniotic fluid concentrations of sRAGE and esRAGE. Changes in the amniotic fluid concentration of sRAGE and esRAGE may represent part of the immune response to intra-amniotic infection/inflammation. 相似文献
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Orianne Constant Patricia Gil Jonathan Barthelemy Karine Bollor Vincent Foulongne Caroline Desmetz Agns Leblond Isabelle Desjardins Sophie Pradier Aurlien Jouli Alain Sandoz Rayane Amaral Michel Boisseau Ignace Rakotoarivony Thierry Baldet Albane Marie Benoît Frances Florence Reboul Salze Bachirou Tinto Philippe Van de Perre Sara Salinas Ccile Beck Sylvie Lecolinet Serafin Gutierrez Yannick Simonin 《Euro surveillance : bulletin européen sur les maladies transmissibles = European communicable disease bulletin》2022,27(25)
BackgroundWest Nile virus (WNV) and Usutu virus (USUV), two closely related flaviviruses, mainly follow an enzootic cycle involving mosquitoes and birds, but also infect humans and other mammals. Since 2010, their epidemiological situation may have shifted from irregular epidemics to endemicity in several European regions; this requires confirmation, as it could have implications for risk assessment and surveillance strategies.AimTo explore the seroprevalence in animals and humans and potential endemicity of WNV and USUV in Southern France, given a long history of WNV outbreaks and the only severe human USUV case in France in this region.MethodsWe evaluated the prevalence of WNV and USUV in a repeated cross-sectional study by serological and molecular analyses of human, dog, horse, bird and mosquito samples in the Camargue area, including the city of Montpellier, between 2016 and 2020.ResultsWe observed the active transmission of both viruses and higher USUV prevalence in humans, dogs, birds and mosquitoes, while WNV prevalence was higher in horses. In 500 human samples, 15 were positive for USUV and 6 for WNV. Genetic data showed that the same lineages, WNV lineage 1a and USUV lineage Africa 3, were found in mosquitoes in 2015, 2018 and 2020.ConclusionThese findings support existing literature suggesting endemisation in the study region and contribute to a better understanding of USUV and WNV circulation in Southern France. Our study underlines the importance of a One Health approach for the surveillance of these viruses. 相似文献
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Eleonora Loi Cesare Zavattari Alessandro Tommasi Loredana Moi Matteo Canale Agnese Po Claudia Sabato Ana Florencia Vega-Benedetti Pina Ziranu Marco Puzzoni Eleonora Lai Luca Faloppi María Rulln Juan Carrascosa Irene Amat Jesús M. Urman Maria Arechederra Carmen Berasain Elisabetta Ferretti Andrea Casadei-Gardini Matías A. Avila Sergio Alonso Mario Scartozzi Patrizia Zavattari 《British journal of cancer》2022,126(12):1783
Background Biliary tract cancers (BTC) are rare but highly aggressive tumours with poor prognosis, usually detected at advanced stages. Herein, we aimed at identifying BTC-specific DNA methylation alterations.Methods Study design included statistical power and sample size estimation. A genome-wide methylation study of an explorative cohort (50 BTC and ten matched non-tumoral tissue samples) has been performed. BTC-specific altered CpG islands were validated in over 180 samples (174 BTCs and 13 non-tumoral controls). The final biomarkers, selected by a machine-learning approach, were validated in independent tissue (18 BTCs, 14 matched non-tumoral samples) and bile (24 BTCs, five non-tumoral samples) replication series, using droplet digital PCR.Results We identified and successfully validated BTC-specific DNA methylation alterations in over 200 BTC samples. The two-biomarker panel, selected by an in-house algorithm, showed an AUC > 0.97. The best-performing biomarker (chr2:176993479-176995557), associated with HOXD8, a pivotal gene in cancer-related pathways, achieved 100% sensitivity and specificity in a new series of tissue and bile samples.Conclusions We identified a novel fully efficient BTC biomarker, associated with HOXD8 gene, detectable both in tissue and bile by a standardised assay ready-to-use in clinical trials also including samples from non-invasive matrices.Subject terms: Diagnostic markers, Biliary tract cancer 相似文献