全文获取类型
收费全文 | 17794篇 |
免费 | 871篇 |
国内免费 | 114篇 |
专业分类
耳鼻咽喉 | 103篇 |
儿科学 | 597篇 |
妇产科学 | 508篇 |
基础医学 | 2026篇 |
口腔科学 | 509篇 |
临床医学 | 1322篇 |
内科学 | 4671篇 |
皮肤病学 | 313篇 |
神经病学 | 1844篇 |
特种医学 | 791篇 |
外国民族医学 | 2篇 |
外科学 | 2405篇 |
综合类 | 52篇 |
一般理论 | 2篇 |
预防医学 | 758篇 |
眼科学 | 225篇 |
药学 | 980篇 |
中国医学 | 12篇 |
肿瘤学 | 1659篇 |
出版年
2023年 | 120篇 |
2022年 | 126篇 |
2021年 | 381篇 |
2020年 | 264篇 |
2019年 | 377篇 |
2018年 | 473篇 |
2017年 | 355篇 |
2016年 | 467篇 |
2015年 | 479篇 |
2014年 | 675篇 |
2013年 | 867篇 |
2012年 | 1318篇 |
2011年 | 1314篇 |
2010年 | 762篇 |
2009年 | 684篇 |
2008年 | 1264篇 |
2007年 | 1133篇 |
2006年 | 1201篇 |
2005年 | 1109篇 |
2004年 | 1089篇 |
2003年 | 975篇 |
2002年 | 897篇 |
2001年 | 177篇 |
2000年 | 128篇 |
1999年 | 192篇 |
1998年 | 147篇 |
1997年 | 125篇 |
1996年 | 103篇 |
1995年 | 132篇 |
1994年 | 111篇 |
1993年 | 117篇 |
1992年 | 112篇 |
1991年 | 96篇 |
1990年 | 97篇 |
1989年 | 85篇 |
1988年 | 68篇 |
1987年 | 72篇 |
1986年 | 73篇 |
1985年 | 52篇 |
1984年 | 82篇 |
1983年 | 47篇 |
1982年 | 56篇 |
1981年 | 39篇 |
1980年 | 46篇 |
1979年 | 27篇 |
1978年 | 35篇 |
1977年 | 24篇 |
1976年 | 19篇 |
1974年 | 20篇 |
1972年 | 17篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
1.
Davide Fiore Bavaro Flavia Balena Luigi Ronga Fabio Signorile Federica Romanelli Stefania Stolfa Eleonora Sparapano Carmela De Carlo Adriana Mosca Laura Monno Gioacchino Angarano Annalisa Saracino 《Journal de Mycologie Médicale》2022,32(1):101206
An increased number of patients is at risk of Candida spp. bloodstream infection (CBSI) in modern medicine. Moreover, the rising of antifungal resistance (AR) was recently reported. All consecutive CBSI occurred in our Hospital (consisting of 1,370 beds) between 2015 and 2018, were reviewed. For each case, Candida species, AR pattern, ward involved and demographic data of patients were recorded. Overall, 304 episodes of CBSI occurred, with a median (q1:first-,q3:third quartile) of 77 (71-82) CBSI/year. Over the years, a significant increase of CBSI due to C. albicans compared to non-albicans strains was recorded in medical wards (from 65% to 71%, p=0.030), while this ratio remained stable in others. An increase of resistant strains to multiple antifungals such as C. guillermondii was noticed in recent years (from 0% to 9.8%, p=0.008). Additionally, from 2015 to 2018 an increase in fluconazole-resistance was recorded in our Hospital (from 7.4% to 17.4%, p=0.025) and a slight increase in voriconazole-resistance (from 0% to 7% in 2018, p=0.161) was observed, while resistance to echinocandin and amphotericin B remained firmly below 2%.This study suggests a rapid spread of antifungal resistance in our Hospital; therefore, an appropriate antifungal stewardship programs is urgently warranted. 相似文献
2.
Carlo Romano Settanni Gianluca Ianiro Francesca Romana Ponziani Stefano Bibb Jonathan Philip Segal Giovanni Cammarota Antonio Gasbarrini 《World journal of gastroenterology : WJG》2021,27(43):7433-7445
In December 2019 a novel coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), started spreading from Wuhan city of Chinese Hubei province and rapidly became a global pandemic. Clinical symptoms of the disease range from paucisymptomatic disease to a much more severe disease. Typical symptoms of the initial phase include fever and cough, with possible progression to acute respiratory distress syndrome. Gastrointestinal manifestations such as diarrhoea, vomiting and abdominal pain are reported in a considerable number of affected individuals and may be due to the SARS-CoV-2 tropism for the peptidase angiotensin receptor 2. The intestinal homeostasis and microenvironment appear to play a major role in the pathogenesis of COVID-19 and in the enhancement of the systemic inflammatory responses. Long-term consequences of COVID-19 include respiratory disturbances and other disabling manifestations, such as fatigue and psychological impairment. To date, there is a paucity of data on the gastrointestinal sequelae of SARS-CoV-2 infection. Since COVID-19 can directly or indirectly affect the gut physiology in different ways, it is plausible that functional bowel diseases may occur after the recovery because of potential pathophysiological alterations (dysbiosis, disruption of the intestinal barrier, mucosal microinflammation, post-infectious states, immune dysregulation and psychological stress). In this review we speculate that COVID-19 can trigger irritable bowel syndrome and we discuss the potential mechanisms. 相似文献
3.
4.
Marco Bologna Giuseppina Calareso Carlo Resteghini Silvana Sdao Eros Montin Valentina Corino Luca Mainardi Lisa Licitra Paolo Bossi 《NMR in biomedicine》2022,35(4):e4265
In this paper, several radiomics-based predictive models of response to induction chemotherapy (IC) in sinonasal cancers (SNCs) are built and tested. Models were built as a combination of radiomic features extracted from three types of MRI images: T1-weighted images, T2-weighted images and apparent diffusion coefficient (ADC) maps. Fifty patients (aged 54 ± 12 years, 41 men) were included in this study. Patients were classified according to their response to IC (25 responders and 25 nonresponders). Not all types of images were acquired for all of the patients: 49 had T1-weighted images, 50 had T2-weighted images and 34 had ADC maps. Only in a subset of 33 patients were all three types of image acquired. Eighty-nine radiomic features were extracted from the MRI images. Dimensionality reduction was performed by using principal component analysis (PCA) and by selecting only the three main components. Different algorithms (trees ensemble, K-nearest neighbors, support vector machine, naïve Bayes) were used to classify the patients as either responders or nonresponders. Several radiomic models (either monomodality or multimodality obtained by a combination of T1-weighted, T2-weighted and ADC images) were developed and the performance was assessed through 100 iterations of train and test split. The area under the curve (AUC) of the models ranged from 0.56 to 0.78. Trees ensemble, support vector machine and naïve Bayes performed similarly, but in all cases ADC-based models performed better. Trees ensemble gave the highest AUC (0.78 for the T1-weighted+T2-weighted+ADC model) and was used for further analyses. For trees ensemble, the models based on ADC features performed better than those models that did not use those features (P < 0.02 for one-tail Hanley test, AUC range 0.68–0.78 vs 0.56–0.69) except the T1-weighted+ADC model (AUC 0.71 vs 0.69, nonsignificant differences). The results suggest the relevance of ADC-based radiomics for prediction of response to IC in SNCs. 相似文献
5.
Scala Marcello Brigati Giorgia Fiorillo Chiara Nesti Claudia Rubegni Anna Pedemonte Marina Bruno Claudio Severino Mariasavina Derchi Maria Minetti Carlo Santorelli F. M. 《Neurogenetics》2019,20(3):165-172
neurogenetics - TSFM is a nuclear gene encoding the elongation factor Ts (EFTs), an essential component of mitochondrial translational machinery. Impaired mitochondrial translation is responsible... 相似文献
6.
Valentina Guercio Francesca Donato Claudio Pelucchi Federica Verga Valter Passini Carlotta Galeone Eva Negri Giacomo Garzaro Paolo Boffetta Carlo La Vecchia Alessandra Tavani Enrico Pira 《La Medicina del lavoro》2019,110(5):342
Background::Soft tissue sarcoma (STS) is a heterogeneous group of rare neoplasms whose aetiology is largely unknown. Dioxin and dioxin-like compounds, including 2,3,7,8-tetrachlorodibenzo-p-dioxin (2,3,7,8-TCDD) and polychlorinated biphenyls (PCBs), are potential risk factors for STS.Objectives:To investigate the relation of 17 PCBs congeners, assessed in human plasma, with STS risk.Methods:We conducted a case-control study in Italy, including 52 STS cases and 99 hospital-based controls. Selected PCB were extracted by high-performance liquid chromatography (HPLC) and measured with gas chromatography-mass spectrometry (GC-MS). Odds ratios (OR), and the corresponding 95% confidence intervals (CI), were estimated through multivariate logistic regression models.Results:The most frequently detected PCB congeners were 138, 170, 180 and 149 (detected in 40-77% of controls). The OR for the sum of all 17 PCB congeners was 1.20 (95% CI 0.50-2.92). In categorical analysis no consistent association was found for individual congeners and for groups based on Wolff’s classification or the degree of chlorination. For continuous estimates, borderline positive associations emerged for Wolff’s groups 2A (OR 1.23, 95% CI 0.97-1.55), 2B (OR 1.34, 95% CI 1.00-1.77, and 3 (OR 1.19, 95% CI 0.96-1.49), for moderately (OR 1.20, 95% CI 0.96-1.51) and highly (OR 1.18, 95% CI 0.99-1.41) chlorinated PCBs, and for congeners 170 (OR 1.26, 95% CI 0.98-1.63), 180 (OR 1.26, 95% CI 0.97-1.64) and 138 (OR 1.45, 95% CI 1.02-2.04).Discussion:Most associations between PCBs and STS risk were not significant, but, given the limited sample size, we cannot exclude moderate associations.Key words: Soft tissue sarcoma, polychlorinated biphenyls, epidemiology, environmental risk factors, chemical contaminants, case-control study 相似文献
7.
Perri Roberta Monaco Marco Fadda Lucia Caltagirone Carlo Carlesimo Giovanni A. 《Journal of neurology》2019,266(10):2447-2456
Journal of Neurology - Patients with subcortical ischemic vascular dementia (SIVD) perform better than Alzheimer’s disease patients (AD) on the Free and Cued Recall Selective Reminding test... 相似文献
8.
Mei Yin Wong Katrina A. Andrews Benjamin G. Challis Soo‐Mi Park Carlo L. Acerini Eamonn R. Maher Ruth T. Casey 《Clinical endocrinology》2019,90(4):499-505
The succinate dehydrogenase (SDH) enzyme complex functions as a key enzyme coupling the oxidation of succinate to fumarate in the citric acid cycle. Inactivation of this enzyme complex results in the cellular accumulation of the oncometabolite succinate, which is postulated to be a key driver in tumorigenesis. Succinate accumulation inhibits 2‐oxoglutarate‐dependent dioxygenases, including DNA and histone demethylase enzymes and hypoxic gene response regulators. Biallelic inactivation (typically resulting from one inherited and one somatic event) at one of the four genes encoding the SDH complex (SDHA/B/C/D) is the most common cause for SDH deficient (dSDH) tumours. Germline mutations in the SDHx genes predispose to a spectrum of tumours including phaeochromocytoma and paraganglioma (PPGL), wild type gastrointestinal stromal tumours (wtGIST) and, less commonly, renal cell carcinoma and pituitary tumours. Furthermore, mutations in the SDHx genes, particularly SDHB, predispose to a higher risk of malignant PPGL, which is associated with a 5‐year mortality of 50%. There is general agreement that biochemical and imaging surveillance should be offered to asymptomatic carriers of SDHx gene mutations in the expectation that this will reduce the morbidity and mortality associated with dSDH tumours. However, there is no consensus on when and how surveillance should be performed in children and young adults. Here, we address the question: “What age should clinical, biochemical and radiological surveillance for PPGL be initiated in paediatric SDHx mutation carriers?”. 相似文献
9.
Adrien Bouglé MD PhD Pierre Rocheteau PhD David Briand MS David Hardy PhD Franck Verdonk MD PhD Carlo Tremolada MD Mikael Hivelin MD PhD Fabrice Chrétien MD PhD 《Muscle & nerve》2019,60(3):328-335
Introduction: No etiologic therapy is available for Duchenne muscular dystrophy (DMD), but mesenchymal stem cells were shown to be effective in preclinical models of DMD. The objective of this study is to investigate the effect of microfragmented fat extracted on a murine model of DMD. Methods: Fat tissue was extracted from healthy human participants and injected IM into DMD mice. Histological analysis, cytokines, and force measurement were performed up to 4 weeks after injection. Results: Duchenne muscular dystrophy mice injected with microfragmented fat exhibited an improved muscle phenotype (decreased necrosis and fibrosis), a decrease of inflammatory cytokines, and increased strength. Discussion: Administration of microfragmented fat in key muscles may improve muscular phenotype in patients with DMD. Muscle Nerve, 2019 相似文献