全文获取类型
收费全文 | 901722篇 |
免费 | 63665篇 |
国内免费 | 2338篇 |
专业分类
耳鼻咽喉 | 12522篇 |
儿科学 | 28775篇 |
妇产科学 | 26216篇 |
基础医学 | 126934篇 |
口腔科学 | 24747篇 |
临床医学 | 74984篇 |
内科学 | 183973篇 |
皮肤病学 | 19016篇 |
神经病学 | 71648篇 |
特种医学 | 36572篇 |
外国民族医学 | 336篇 |
外科学 | 142511篇 |
综合类 | 19049篇 |
一般理论 | 250篇 |
预防医学 | 64720篇 |
眼科学 | 20104篇 |
药学 | 63964篇 |
中国医学 | 1806篇 |
肿瘤学 | 49598篇 |
出版年
2018年 | 9129篇 |
2017年 | 7228篇 |
2016年 | 7736篇 |
2015年 | 8821篇 |
2014年 | 12466篇 |
2013年 | 19358篇 |
2012年 | 25894篇 |
2011年 | 27494篇 |
2010年 | 16686篇 |
2009年 | 15872篇 |
2008年 | 26288篇 |
2007年 | 27898篇 |
2006年 | 28059篇 |
2005年 | 27601篇 |
2004年 | 26455篇 |
2003年 | 25606篇 |
2002年 | 25179篇 |
2001年 | 41426篇 |
2000年 | 42637篇 |
1999年 | 36334篇 |
1998年 | 9996篇 |
1997年 | 9171篇 |
1996年 | 9105篇 |
1995年 | 8469篇 |
1994年 | 8089篇 |
1993年 | 7596篇 |
1992年 | 28232篇 |
1991年 | 27022篇 |
1990年 | 26451篇 |
1989年 | 25379篇 |
1988年 | 23593篇 |
1987年 | 23202篇 |
1986年 | 22285篇 |
1985年 | 21186篇 |
1984年 | 15830篇 |
1983年 | 13499篇 |
1982年 | 8097篇 |
1979年 | 14611篇 |
1978年 | 10218篇 |
1977年 | 8644篇 |
1976年 | 8155篇 |
1975年 | 8968篇 |
1974年 | 10703篇 |
1973年 | 10190篇 |
1972年 | 9667篇 |
1971年 | 8922篇 |
1970年 | 8588篇 |
1969年 | 8035篇 |
1968年 | 7689篇 |
1967年 | 7093篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
J.A. Hannam S.J. Mitchell D. Cumin C. Frampton A.F. Merry M.R. Moore C.J. Kruger 《British journal of anaesthesia》2019,122(2):198-205
Background
Etomidate is frequently selected over propofol for induction of anaesthesia because of a putatively favourable haemodynamic profile, but data confirming this perception are limited.Methods
Patients undergoing cardiac surgery were randomised to induction of anaesthesia with propofol or etomidate. Phase I (n=75) was conducted as open-label, whereas Phase II (n=75) was double blind. Mean arterial blood pressure (MAP) and boluses of vasopressor administered after induction were recorded. The primary endpoint was the area under the curve below baseline MAP (MAP-time integral) during the 10 min after induction. Secondary endpoints were the use of vasopressors over the same period, and the effect of blinding on the aforementioned endpoints. Groups were compared using regression models with phase and anaesthetist as factors.Results
The mean difference between etomidate and propofol in the MAP-time integral below baseline was 2244 mm Hg s (95% confidence interval, 581–3906; P=0.009), representing a 34% greater reduction with propofol. Overall, vasopressors were used in 10/75 patients in the etomidate group vs 21/75 in the propofol group (P=0.38), and in 20/74 patients during the blinded phase vs 11/76 during the open-label phase (P=0.31). The interaction between randomisation and phase (open-labelled or blinded) was not significant for either primary (P=0.73) or secondary endpoints (P=0.90).Conclusions
Propofol caused a 34% greater reduction in MAP-time integral from baseline after induction of anaesthesia than etomidate, despite more frequent use of vasopressors with propofol, confirming the superior haemodynamic profile of etomidate in this context. The proportion of patients receiving vasopressors increased slightly, albeit not significantly, in both groups in the blinded phase.Clinical trial registration
Australian and New Zealand Clinical Trials Registry, ACTRN12614000717651. 相似文献122.
123.
124.
125.
Matthew D. Li Katrina F. Chu Allegra DePietro Vincent Wu Eric Wehrenberg-Klee Omar Zurkiya Raymond W. Liu Suvranu Ganguli 《Journal of vascular and interventional radiology : JVIR》2019,30(3):314-319
Purpose
To evaluate the feasibility of a same-day yttrium-90 (90Y) radioembolization protocol with resin microspheres (including pretreatment angiography, lung shunt fraction [LSF] determination, and radioembolization) for the treatment of hepatocellular carcinoma (HCC) and liver metastases.Materials and Methods
All same-day radioembolization procedures performed over 1 y (February 2017 to January 2018) were included in this single-institutional retrospective analysis, in which 34 procedures were performed in 26 patients (median age, 63 y; 13 women), 19 with liver metastases and 7 with HCC. Yttrium-90 treatment activities were calculated by body surface area method. Tumor imaging response was assessed by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1 for liver metastases and modified RECIST for HCC. Clinical side effects and adverse events were graded per Common Terminology Criteria for Adverse Events version 4.0.Results
All planned cases were technically successful, and no cases were canceled for elevated LSF or vascular anatomic reasons. Pretreatment angiography modified the planned 90Y treatment activity in 1 case in which vascular anatomy required a lobar-dose split into 2 for segmental infusions. In 18% of cases, patients were briefly admitted after the procedure for observation or symptom management. Imaging evaluation of initial efficacy at 1 month demonstrated partial response in 25% and stable disease in 67% of patients with liver metastases and partial/complete response in 43% and stable disease in 14% of patients with HCC. Grade ≥ 3 adverse events occurred in 6% of cases, with no systemic therapy–limiting toxicities. The mean total procedure time was 4.2 hours.Conclusions
A same-day 90Y radioembolization protocol with resin microspheres is feasible in select patients, which can expedite cancer therapy. 相似文献126.
C. Jacquet F. Goehringer E. Baux J.A. Conrad M.O. Ganne Devonec J.L. Schmutz G. Mathey H. Tronel T. Moulinet I. Chary-Valckenaere T. May C. Rabaud 《Médecine et maladies infectieuses》2019,49(2):112-120
Objective
The teaching hospital of Nancy, France, implemented a specific multidisciplinary care pathway (French acronym AMDPL) to improve the management of patients presenting with Lyme borreliosis (LB) suspicion. We aimed to assess the first year of activity of this care pathway.Patients and methods
We included all patients managed in the AMDPL pathway from November 1, 2016 to October 31, 2017. The first step was a dedicated Lyme disease consultation with an infectious disease specialist. Following this consultation, the LB diagnosis was either confirmed and adequate treatment was prescribed, or a differential diagnosis was established and patients received adequate management, or further investigations were required and patients were offered multidisciplinary management as part of a day hospitalization.Results
A total of 468 patients were included. LB diagnosis was confirmed in 15% of patients (69/468), 49% of patients received a differential diagnosis, and 26% (122/468) of patients had the LB diagnosis ruled out without receiving any other diagnosis.Conclusions
This is to our knowledge the first multidisciplinary center implemented in France for the management of patients presenting with LB suspicion related to polymorphous signs and symptoms. Several diagnoses could be confirmed or corrected, although some symptoms and complaints could not be explained. This cohort could improve our knowledge of LB and its differential diagnoses. 相似文献127.
de Oliveira Adilson J M Solla Davi J. F. de Oliveira Klever F. Amaral Bruno S. Andrade Almir F. Kolias Angelos G. Paiva Wellingson S. 《Neurological sciences》2022,43(1):427-434
Neurological Sciences - Chronic subdural haematoma (CSDH) is one of the most common neurosurgical pathologies. The recurrence of chronic subdural haematomas is an important concern, considering... 相似文献
128.
129.
130.
Carlos A. ávila-Orta Zoe V. Qui?ones-Jurado Miguel A. Waldo-Mendoza Erika A. Rivera-Paz Víctor J. Cruz-Delgado José M. Mata-Padilla Pablo González-Morones Ronald F. Ziolo 《Materials》2015,8(11):7900-7912
Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 1013 to 105 Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods. 相似文献