全文获取类型
收费全文 | 11450篇 |
免费 | 502篇 |
国内免费 | 39篇 |
专业分类
耳鼻咽喉 | 303篇 |
儿科学 | 277篇 |
妇产科学 | 302篇 |
基础医学 | 1581篇 |
口腔科学 | 442篇 |
临床医学 | 930篇 |
内科学 | 2618篇 |
皮肤病学 | 213篇 |
神经病学 | 1290篇 |
特种医学 | 222篇 |
外科学 | 1020篇 |
综合类 | 21篇 |
一般理论 | 6篇 |
预防医学 | 650篇 |
眼科学 | 135篇 |
药学 | 701篇 |
1篇 | |
中国医学 | 37篇 |
肿瘤学 | 1242篇 |
出版年
2024年 | 94篇 |
2023年 | 125篇 |
2022年 | 276篇 |
2021年 | 436篇 |
2020年 | 287篇 |
2019年 | 331篇 |
2018年 | 351篇 |
2017年 | 289篇 |
2016年 | 353篇 |
2015年 | 373篇 |
2014年 | 499篇 |
2013年 | 603篇 |
2012年 | 932篇 |
2011年 | 1048篇 |
2010年 | 518篇 |
2009年 | 454篇 |
2008年 | 787篇 |
2007年 | 720篇 |
2006年 | 641篇 |
2005年 | 671篇 |
2004年 | 604篇 |
2003年 | 548篇 |
2002年 | 481篇 |
2001年 | 58篇 |
2000年 | 34篇 |
1999年 | 52篇 |
1998年 | 88篇 |
1997年 | 61篇 |
1996年 | 44篇 |
1995年 | 46篇 |
1994年 | 34篇 |
1993年 | 32篇 |
1992年 | 23篇 |
1991年 | 12篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 8篇 |
1987年 | 2篇 |
1986年 | 15篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 6篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1976年 | 3篇 |
1974年 | 5篇 |
1973年 | 2篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Alessandro Cipriano Alessio Pecori Alessandra Eugenia Bionda Michele Bardini Francesca Frassi Francesco Leoli Valentina Lami Lorenzo Ghiadoni Massimo Santini 《Internal and emergency medicine》2018,13(7):1077-1087
Prognosis after mild traumatic brain injury (MTBI) on oral anticoagulant therapy (OAT) is uncertain. We evaluated the rate of immediate and delayed traumatic intracranial hemorrhage (ICH) comparing vitamin K antagonists (VKAs) to direct oral anticoagulants (DOACs) and the safety of a clinical management protocol. In this single-center prospective observational study, we enrolled 220 patients on OAT with MTBI. After a first negative CT scan, asymptomatic patients underwent a close neurological observation; if neurologically stable, they were discharged without a second CT scan and followed up for 1 month. Out of the 220 patients, 206 met the inclusion criteria. 23 of them (11.2%) had a positive first CT scan for ICH. Only 1 (0.5%, 95% CI 0.0–1.4%) died because of ICH; no one required neurosurgical intervention. The observed prevalence rate of immediate ICH resulted statistically higher in VKAs-treated patients compared to those treated with DOACs (15.7 vs. 4.7%, RR 3.34, 95% CI 1.18–9.46, P?<?0.05). In the 1-month follow-up, 5 out of the 183 patients with a negative CT scan were lost. Out of the remaining 178 patients, only 3 showed a delayed ICH (1.7%, 95% CI 0.0–3.6%), 1 of them died (0.6%, 95% CI 0.5–1.7%) and the others did not require neurosurgical intervention. DOACs resulted safer than VKAs also in the setting of MTBI. In our observation, the rate of delayed hemorrhage was relatively low. Patients presenting with a negative first CT scan and without neurological deterioration could be safely discharged after a short period of in-ward observation with a low rate of complications and without a second CT scan. 相似文献
92.
Beatriz Moreno MD Ana Paula de Faria PhD Alessandra Mileni Versuti Ritter PhD Lara Buonalumi Tacito Yugar MD Silvia Elaine Ferreira‐Melo PhD Rivadavio Amorim MSc Rodrigo Modolo MD PhD André Fattori MD PhD Juan Carlos Yugar‐Toledo MD PhD Antonio Coca MD PhD Heitor Moreno MD PhD 《Journal of clinical hypertension (Greenwich, Conn.)》2018,20(5):910-917
This study aimed to evaluate the effects of glycated hemoglobin (HbA1c) on flow‐mediated dilation, intima‐media thickness, pulse wave velocity, and left ventricular mass index in patients with resistant hypertension (RHTN) comparing RHTN–controlled diabetes mellitus and RHTN–uncontrolled type 2 diabetes mellitus. Two groups were formed: HbA1c <7.0% (RHTN–controlled diabetes mellitus: n = 98) and HbA1c ≥7.0% (RHTN–uncontrolled diabetes mellitus: n = 122). Intima‐media thickness and flow‐mediated dilation were measured by high‐resolution ultrasound, left ventricular mass index by echocardiography, and arterial stiffness by carotid‐femoral pulse wave velocity. No differences in blood pressure levels were found between the groups but body mass index was higher in patients with RHTN–uncontrolled diabetes mellitus. Endothelial dysfunction and arterial stiffness were worse in patients with RHTN–uncontrolled diabetes mellitus. Intima‐media thickness and left ventricular mass index measurements were similar between the groups. After adjustments, multiple linear regression analyses showed that HbA1c was an independent predictor of flow‐mediated dilation and pulse wave velocity in all patients with RHTN. In conclusion, HbA1c may predict the grade of arterial stiffness and endothelial dysfunction in patients with RHTN, and superimposed uncontrolled diabetes mellitus implicates further impairment of vascular function. 相似文献
93.
Chiara Fania Raffaele Pezzilli Gianvico Melzi d’Eril Cecilia Gelfi Alessandra Barassi 《Digestive diseases and sciences》2018,63(4):920-933
Background
There are a limited number of studies investigating the type of serum proteins capable of differentiating intraductal papillary mucinous neoplasms from benign or malignant diseases of the pancreas.Aims
To select proteins able to differentiate intraductal papillary mucinous neoplasms from benign and malignant pancreatic disease using semiquantitative proteomics.Methods
Serum samples were obtained from 74 patients (19 with type II intraductal papillary mucinous neoplasms, 8 with type I/III intraductal papillary mucinous neoplasms, 24 with chronic pancreatitis, 23 with pancreatic ductal adenocarcinomas) and 21 healthy subjects. Small proteins and peptides were assayed by matrix-assisted laser desorption/ionization for the detection of differentially abundant species possibly related to tumor onset. Serum pancreatic amylase, lipase, carcinoembryonic antigen and carbohydrate antigen 19-9 (CA 19-9) were also assayed.Results
Twenty-six of 84 peaks detected were dysregulated (7 more abundant and 19 less abundant in the type II intraductal papillary mucinous neoplasms, p < 0.05). Of the differentially abundant peaks, 17 were commonly dysregulated (3 peaks more abundant and 13 less abundant in type II intraductal papillary mucinous neoplasms, and one at m/z = 9961 at variance), indicating a protein fingerprint shared by types I/III and type II intraductal papillary mucinous neoplasms and pancreatic ductal adenocarcinomas.Conclusions
These results suggest that our approach can be used to differentiate type II intraductal papillary mucinous neoplasms from type I/III neoplasms, and type II intraductal papillary mucinous neoplasms from pancreatic ductal adenocarcinomas.94.
95.
Yuetsu Kikuta Christopher M. Cook Andrew S.P. Sharp Pablo Salinas Yoshiaki Kawase Yasutsugu Shiono Alessandra Giavarini Masafumi Nakayama Salvatore De Rosa Sayan Sen Sukhjinder S. Nijjer Rasha Al-Lamee Ricardo Petraco Iqbal S. Malik Ghada W. Mikhail Raffi R. Kaprielian Gilbert W.M. Wijntjens Shinsuke Mori Justin E. Davies 《JACC: Cardiovascular Interventions》2018,11(8):757-767
Objectives
The authors sought to evaluate the accuracy of instantaneous wave-Free Ratio (iFR) pullback measurements to predict post-percutaneous coronary intervention (PCI) physiological outcomes, and to quantify how often iFR pullback alters PCI strategy in real-world clinical settings.Background
In tandem and diffuse disease, offline analysis of continuous iFR pullback measurement has previously been demonstrated to accurately predict the physiological outcome of revascularization. However, the accuracy of the online analysis approach (iFR pullback) remains untested.Methods
Angiographically intermediate tandem and/or diffuse lesions were entered into the international, multicenter iFR GRADIENT (Single instantaneous wave-Free Ratio Pullback Pre-Angioplasty Predicts Hemodynamic Outcome Without Wedge Pressure in Human Coronary Artery Disease) registry. Operators were asked to submit their procedural strategy after angiography alone and then after iFR-pullback measurement incorporating virtual PCI and post-PCI iFR prediction. PCI was performed according to standard clinical practice. Following PCI, repeat iFR assessment was performed and the actual versus predicted post-PCI iFR values compared.Results
Mean age was 67 ± 12 years (81% male). Paired pre- and post-PCI iFR were measured in 128 patients (134 vessels). The predicted post-PCI iFR calculated online was 0.93 ± 0.05; observed actual iFR was 0.92 ± 0.06. iFR pullback predicted the post-PCI iFR outcome with 1.4 ± 0.5% error. In comparison to angiography-based decision making, after iFR pullback, decision making was changed in 52 (31%) of vessels; with a reduction in lesion number (?0.18 ± 0.05 lesion/vessel; p = 0.0001) and length (?4.4 ± 1.0 mm/vessel; p < 0.0001).Conclusions
In tandem and diffuse coronary disease, iFR pullback predicted the physiological outcome of PCI with a high degree of accuracy. Compared with angiography alone, availability of iFR pullback altered revascularization procedural planning in nearly one-third of patients. 相似文献96.
97.
Giorgio Valerii Rosario Landi Ivo Boškoski Pietro Familiari Alessandra Bizzotto 《Scandinavian journal of gastroenterology》2018,53(4):490-494
Objective: We investigate the efficiency of endoscopic mucosal resection (EMR) of non-ampullary sporadic duodenal adenomas (NASDA) in a retrospective analysis with long-term follow-up.Methods: Consecutive patients undergoing EMR of NASDA between May 2002 and December 2016 were retrospectively identified from an electronic database. Endoscopic follow-up was scheduled after 3, 6 and 12 months for the first year, then yearly for up to five years.Results: EMR of 75 NASDA was performed in 68 patients (56% en-bloc, 44% piecemeal). Retroperitoneal perforations occurred in 3/68 (4.4%) patients, were treated by surgical (n?=?2) or percutaneous (n?=?1) drainage; delayed bleeding was reported in 13/75 (17.3%) resections and was successfully managed by endoscopy (n?=?12) or radiologic embolization (n?=?1). There was no procedure-related mortality. Follow-up was available in 61/68 patients (89.7%) after a median time of 59 months from resection. Residual and recurrent adenoma were diagnosed in 9 (14.5%) and 6 (10.9%) cases, respectively; all but one were successfully retreated endoscopically.Conclusions: EMR for NASDA is effective with a favorable long-term outcome. Local recurrences can be retreated endoscopically. A recall system, patient’s compliance to endoscopic follow-up are mandatory to detect recurrences and their prompt treatment. 相似文献
98.
99.
Alessandra Bizzarro Davide Seripa Adele Acciarri Maria Giovanna Matera Alberto Pilotto Francesco Danilo Tiziano Christina Brahe Carlo Masullo 《European journal of human genetics : EJHG》2009,17(7):938-945
The single nucleotide polymorphisms (SNPs) rs449647, rs769446 and rs405509 in the promoter region of the APOE gene have been variously suggested to be ɛ4-independent risk factors for Alzheimer''s disease (AD). A previous Italian study found that the rs449647 was significantly associated with late-onset AD. The aim of this study was to verify whether these APOE promoter SNPs are genetic risk factors for AD and to investigate their interaction with the common APOE polymorphism. A total of 169 clinically diagnosed AD patients and 99 cognitively intact age-matched controls were included in the study. Significant associations with AD independent from sex, age and APOE/ɛ4 status were found for rs449647 A/A and rs405509 G/G genotypes (positive), and rs449647 A/T and rs405509 T/T genotypes (negative). Haplotype frequency estimation at the APOE locus showed significant associations for the ATG4, ATT4 and ACG3 (positive) and ATT2, ATT3 and TCG3 (negative) haplotypes. Therefore this study confirms the role of the rs449647 A/A genotype as risk factor for AD in Italy and suggests that promoter genotypes and APOE haplotypes might have a complex function in AD-associated genetic risk factors. 相似文献
100.
The lateral intraparietal area (LIP) of the macaque is believed to play a role in the allocation of attention and the plan to make saccadic eye movements. Many studies have shown that LIP neurons generally encode the static spatial location demarked by the receptive field (RF). LIP neurons might also provide information about the features of visual stimuli within the RF. For example, LIP receives input from cortical areas in the dorsal visual pathway that contain many direction-selective neurons. Here we examine direction selectivity of LIP neurons. Animals were only required to fixate while motion stimuli appeared in the RF. To avoid spatial confounds, the motion stimuli were patches of randomly arrayed dots that moved with 100% coherence in eight different directions. We found that the majority (61%) of LIP neurons were direction selective. The direction tuning was fairly broad, with a median direction-tuning bandwidth of 136 degrees. The average strength of direction selectivity was weaker in LIP than that of other areas of the dorsal visual stream but that difference may be because of the fact that LIP neurons showed a tonic offset in firing whenever a visual stimulus was in the RF, independent of direction. Direction-selective neurons do not seem to constitute a functionally distinct subdivision within LIP, because those neurons had robust, sustained delay-period activity during a memory delayed saccade task. The direction selectivity could also not be explained by asymmetries in the spatial RF, in the hypothetical case that the animals attended to slightly different locations depending on the direction of motion in the RF. Our results show that direction selectivity is a distinct attribute of LIP neurons in addition to spatial encoding. 相似文献