全文获取类型
收费全文 | 4121篇 |
免费 | 309篇 |
国内免费 | 31篇 |
专业分类
耳鼻咽喉 | 39篇 |
儿科学 | 120篇 |
妇产科学 | 66篇 |
基础医学 | 546篇 |
口腔科学 | 67篇 |
临床医学 | 423篇 |
内科学 | 927篇 |
皮肤病学 | 48篇 |
神经病学 | 382篇 |
特种医学 | 203篇 |
外科学 | 650篇 |
综合类 | 22篇 |
一般理论 | 1篇 |
预防医学 | 215篇 |
眼科学 | 49篇 |
药学 | 380篇 |
中国医学 | 4篇 |
肿瘤学 | 319篇 |
出版年
2023年 | 27篇 |
2022年 | 44篇 |
2021年 | 107篇 |
2020年 | 65篇 |
2019年 | 109篇 |
2018年 | 123篇 |
2017年 | 80篇 |
2016年 | 97篇 |
2015年 | 117篇 |
2014年 | 157篇 |
2013年 | 181篇 |
2012年 | 310篇 |
2011年 | 287篇 |
2010年 | 174篇 |
2009年 | 157篇 |
2008年 | 255篇 |
2007年 | 264篇 |
2006年 | 266篇 |
2005年 | 247篇 |
2004年 | 213篇 |
2003年 | 229篇 |
2002年 | 222篇 |
2001年 | 17篇 |
2000年 | 21篇 |
1999年 | 25篇 |
1998年 | 49篇 |
1997年 | 46篇 |
1996年 | 29篇 |
1995年 | 23篇 |
1994年 | 17篇 |
1993年 | 18篇 |
1992年 | 12篇 |
1991年 | 13篇 |
1989年 | 12篇 |
1988年 | 26篇 |
1986年 | 14篇 |
1985年 | 20篇 |
1984年 | 15篇 |
1983年 | 18篇 |
1982年 | 10篇 |
1981年 | 21篇 |
1980年 | 18篇 |
1978年 | 12篇 |
1977年 | 16篇 |
1976年 | 19篇 |
1975年 | 12篇 |
1973年 | 18篇 |
1965年 | 10篇 |
1964年 | 10篇 |
1960年 | 11篇 |
排序方式: 共有4461条查询结果,搜索用时 31 毫秒
61.
Nassim Hammoudi Marion Dhooge Romain Coriat Sarah Leblanc Maximilien Barret Benoit Bordacahar Frederic Beuvon Frederic Prat Fanny Maksimovic Stanislas Chaussade 《Digestive and liver disease》2019,51(2):299-303
Background and aims
Lynch syndrome (LS) is associated with an increased risk of small bowel tumors but routine screening is not recommended in international guidelines. The aim of our study was to determinate the prevalence of duodenal tumors in a French cohort of LS patients.Methods
Patients carrying a germline pathogenic variant in a MMR gene, supported by our local network, in which at least one upper endoscopy had been performed, were included. We registered the occurrence of duodenal lesions in those patients.Results
154 LS patients were identified including respectively 85 MSH2 and 41 MLH1 mutated patients respectively. Seven out of 154 (4.5%) had at least one duodenal lesion. Median age at diagnosis was 58 years (range: 49–73). The twelve lesions locations were: descending duodenum (n?=?7), genu inferius (n?=?2), duodenal bulb (n?=?1), ampulla (n?=?1), fourth duodenum (n?=?1). Three lesions were invasive adenocarcinomas. The incidence rate of duodenal lesions in patients with MSH2 or MLH1 pathogenic variants was respectively 7.1% (6 out of 85) and 2.4% (1 out of 41) emphasizing a trend toward increased risk of developing duodenal lesion in MSH2 mutated patients: OR: 5.17, IC95% (0.8–60.07), p?=?0.1307.Conclusion
Regarding this high prevalence rate, especially in MSH2 patients, regular duodenal screening during upper endoscopy should be considered in routine in LS patients. 相似文献62.
Mutations of the Imprinted CDKN1C Gene as a Cause of the Overgrowth Beckwith–Wiedemann Syndrome: Clinical Spectrum and Functional Characterization 下载免费PDF全文
Frederic Brioude Irène Netchine Francoise Praz Marilyne Le Jule Claire Calmel Didier Lacombe Patrick Edery Martin Catala Sylvie Odent Bertrand Isidor Stanislas Lyonnet Sabine Sigaudy Bruno Leheup Séverine Audebert‐Bellanger Lydie Burglen Fabienne Giuliano Jean‐Luc Alessandri Valérie Cormier‐Daire Fanny Laffargue Sophie Blesson Isabelle Coupier James Lespinasse Patricia Blanchet Odile Boute Clarisse Baumann Michel Polak Berenice Doray Alain Verloes Géraldine Viot Yves Le Bouc Sylvie Rossignol 《Human mutation》2015,36(9):894-902
Beckwith–Wiedemann syndrome (BWS) is an imprinting disorder associating macroglossia, abdominal wall defects, visceromegaly, and a high risk of childhood tumor. Molecular anomalies are mostly epigenetic; however, mutations of CDKN1C are implicated in 8% of cases, including both sporadic and familial forms. We aimed to describe the phenotype of BWS patients with CDKN1C mutations and develop a functional test for CDKN1C mutations. For each propositus, we sequenced the three exons and intron–exon boundaries of CDKN1C in patients presenting a BWS phenotype, including abdominal wall defects, without 11p15 methylation defects. We developed a functional test based on flow cytometry. We identified 37 mutations in 38 pedigrees (50 patients and seven fetuses). Analysis of parental samples when available showed that all mutations tested but one was inherited from the mother. The four missense mutations led to a less severe phenotype (lower frequency of exomphalos) than the other 33 mutations. The following four tumors occurred: one neuroblastoma, one ganglioneuroblastoma, one melanoma, and one acute lymphoid leukemia. Cases of BWS caused by CDKN1C mutations are not rare. CDKN1C sequencing should be performed for BWS patients presenting with abdominal wall defects or cleft palate without 11p15 methylation defects or body asymmetry, or in familial cases of BWS. 相似文献
63.
Purpose of Review
Multidetector row computed tomography (CT) allows noninvasive imaging of the heart and coronary arteries. The purpose of this review is to briefly summarize recent advances in CT hardware and software technology, and machine learning applications for cardiovascular imaging.Recent Findings
In the last decades, there have been significant improvements in CT hardware focusing on faster gantry rotation resulting in improved temporal resolution. Concurrent hardware improvements include improved spatial resolution and higher coverage of the patient, enabling faster acquisition. Advances in cardiac CT software include methods for measurement of noninvasive FFR, coronary plaque characterization, and adipose tissue characteristics around the heart. Machine learning approaches using cardiac CT have been shown to improve both risk of prognosis and lesion-specific ischemia.Summary
Recent advances in CT hardware and software have expanded the clinical utility of CT for cardiovascular imaging. In the next decades, continued advances can be anticipated in these areas, and in machine learning applications in cardiac CT, as they are incorporated into clinical routine for image acquisition, image analysis, and prediction of patient outcomes.64.
Stylianos A. Pyxaras Tom Adriaenssens Emanuele Barbato Giovanni Jacopo Ughi Luigi Di Serafino Frederic De Vroey Gabor Toth Shengxian Tu Johan H. C. Reiber Jeroen J. Bax William Wijns 《The international journal of cardiovascular imaging》2018,34(4):495-502
We sought to assess in-stent variations in fractional flow reserve (FFR) in patients with previous percutaneous coronary intervention (PCI) and to associate any drop in FFR with findings by optical coherence tomography (OCT) imaging. Suboptimal post-PCI FFR values were previously associated with poor outcomes. It is not known to which extent in-stent pressure loss contributes to reduced FFR. In this single-arm observational study, 26 patients who previously underwent PCI with drug-eluting stent or scaffold implantation were enrolled. Motorized FFR pullback during continuous intravenous adenosine infusion and OCT assessments was performed. Post-PCI FFR?<?0.94 was defined as suboptimal. At a median of 63 days after PCI (interquartile range: 59–64 days), 18 out of 26 patients (72%) had suboptimal FFR. The in-stent drop in FFR was significantly higher in patients with suboptimal FFR vs. patients with optimal FFR (0.08?±?0.07 vs. 0.01?±?0.02, p?<?0.001). Receiver operating characteristic curve analysis showed that an in-stent FFR variation of >?0.03 was associated with suboptimal FFR. In patients with suboptimal FFR, the OCT analyses revealed higher mean neointimal area (respectively: 1.06?±?0.80 vs. 0.51?±?0.23 mm2; p?=?0.018) and higher neointimal thickness of covered struts (respectively 0.11?±?0.07 vs. 0.06?±?0.01 mm; p?=?0.021). Suboptimal FFR values following stent-implantation are mainly caused by significant in-stent pressure loss during hyperemia. This finding is associated to a larger neointimal proliferation. 相似文献
65.
66.
Mikhail-Paul Cardinal Samuel Blais Anne Dumas Vincent Hamilton Eric Larose Stéphanie LeBlanc Julie Déry Heynric Grotenhuis Tim Leiner Wadi Mawad Cassandre Têtu Steven C. Greenway Nicole Dahl David Patton Arif Hussain Christian Drolet Gérald Gahide Paul Farand Frederic Dallaire 《The Canadian journal of cardiology》2021,37(3):417-424
BackgroundReference values for cardiac magnetic resonance imaging (cMRI) in children and young adults are scarce. This leads to risk stratification of patients with congenital heart diseases being based on volumes indexed to body surface area (BSA). We aimed to produce cMRI Z score equations for ventricular volumes in children and young adults and to test whether indexing to BSA resulted in an incorrect assessment of ventricular dilation according to sex, body composition, and growth.MethodsWe retrospectively included 372 subjects aged < 26 years with either normal hearts or conditions with no impact on ventricular volumes (reference group), and 205 subjects with repaired tetralogy of Fallot (TOF) aged < 26 years. We generated Z score equations by means of multivariable regression modelling. Right ventricular dilation was assessed with the use of Z scores and compared with indexing to BSA in TOF subjects.ResultsVentricular volume Z scores were independent from age, sex, and anthropometric measurements, although volumes indexed to BSA showed significant residual association with sex and body size. In TOF subjects, indexing overestimated dilation in growing children and underestimated dilation in female compared with male subjects, and in overweight compared with lean subjects.ConclusionsIndexed ventricular volumes measured with cMRI did not completely adjust for body size and resulted in a differential error in the assessment of ventricular dilation according to sex and body size. Our proposed Z score equations solved this problem. Future studies should evaluate if ventricular volumes expressed as Z scores have a better prognostic value than volumes indexed to BSA. 相似文献
67.
Electromechanical time course in frog ventricle: Manipulation of calcium level during voltage clamp 总被引:2,自引:0,他引:2
Frederic Kavaler 《Journal of molecular and cellular cardiology》1974,6(6):575-580
Extracellular calcium concentration was rapidly altered in the “diastolic” interval between two contractions, and also during the time course of a single 10 s clamp pulse. The results strongly suggest that contraction of frog ventricular muscle is largely determined by a continuous, voltage-dependent influx of calcium into the cell, with little or no contribution from mechanisms involving release of calcium from intracellular stores. In addition, contraction can be graded, as a rapid response to alterations in extracellular calcium concentration. 相似文献
68.
Shin David S. Monroe Eric J. Bertino Frederic J. Abad-Santos Matthew Abajian Aaron Chick Jeffrey Forris Beecham 《Cardiovascular and interventional radiology》2022,45(1):131-133
CardioVascular and Interventional Radiology - 相似文献
69.
70.
Richard H. Turnage Frederic E. Eckhauser Aaron I. Vinik William E. Strodel Norman W. Thompson Anne Smid David Smid 《Journal of gastrointestinal cancer》1988,3(6):477-489
Summary Cystic neoplasms of the pancreas (CNP) are rare lesions that can be difficult to diagnose preoperatively. Twenty patients
with cystic neoplasms of the pancreas including five microcystic adenomas, six benign mucinous cystic neoplasms, three malignant
mucinous cystic neoplasms, two solid and papillary epithelial neoplasms, and four cystic neuroendocrine tumors were treated
at a single institution between 1962 and 1987. The average duration of symptoms prior to diagnosis was 10 months. Five patients
were asymptomatic. Forty percent of patients presented with an abdominal mass. Plain abdominal x-rays and UGI barium contrast
studies were never diagnostic. Ultrasonography, computerized tomography (CT) and visceral angiography aided in the correct
diagnosis in 28%, 36%, and 75% of patients studied, respectively. Overall a correct diagnosis was made preoperatively in only
35% of patients. Twelve of 13 patients were correctly diagnosed at laparotomy with intraoperative biopsy. Without biopsy the
mass was misdiagnosed at laparotomy in five of six cases.
CNP must be suspected inany patients who present with an upper abdominal mass with or without abdominal pain and no history of pancreatitis. CT may be
diagnostic in up to one third of cases and should be obtained routinely to demonstrate the proximity of the lesion to other
structures. Visceral angiography should also be obtained prior to operation. A generous incisional biopsy should be obtained
of all pancreatic cysts that are not to be resected. 相似文献