全文获取类型
收费全文 | 11145篇 |
免费 | 624篇 |
国内免费 | 112篇 |
专业分类
耳鼻咽喉 | 184篇 |
儿科学 | 154篇 |
妇产科学 | 243篇 |
基础医学 | 1716篇 |
口腔科学 | 241篇 |
临床医学 | 876篇 |
内科学 | 1984篇 |
皮肤病学 | 566篇 |
神经病学 | 668篇 |
特种医学 | 728篇 |
外科学 | 1808篇 |
综合类 | 57篇 |
一般理论 | 1篇 |
预防医学 | 608篇 |
眼科学 | 183篇 |
药学 | 935篇 |
中国医学 | 157篇 |
肿瘤学 | 772篇 |
出版年
2023年 | 57篇 |
2022年 | 231篇 |
2021年 | 353篇 |
2020年 | 176篇 |
2019年 | 275篇 |
2018年 | 298篇 |
2017年 | 213篇 |
2016年 | 348篇 |
2015年 | 488篇 |
2014年 | 587篇 |
2013年 | 678篇 |
2012年 | 979篇 |
2011年 | 952篇 |
2010年 | 594篇 |
2009年 | 458篇 |
2008年 | 657篇 |
2007年 | 608篇 |
2006年 | 554篇 |
2005年 | 556篇 |
2004年 | 428篇 |
2003年 | 370篇 |
2002年 | 331篇 |
2001年 | 215篇 |
2000年 | 224篇 |
1999年 | 178篇 |
1998年 | 73篇 |
1997年 | 59篇 |
1996年 | 54篇 |
1995年 | 38篇 |
1994年 | 40篇 |
1993年 | 35篇 |
1992年 | 60篇 |
1991年 | 52篇 |
1990年 | 52篇 |
1989年 | 39篇 |
1988年 | 49篇 |
1987年 | 41篇 |
1986年 | 44篇 |
1985年 | 48篇 |
1984年 | 38篇 |
1983年 | 50篇 |
1981年 | 18篇 |
1980年 | 16篇 |
1979年 | 29篇 |
1978年 | 27篇 |
1977年 | 21篇 |
1976年 | 20篇 |
1975年 | 15篇 |
1974年 | 17篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
S.-B. Moon W.-Y. Shin Y.-J. Park S.-J. Kim 《European journal of vascular and endovascular surgery》2009,37(5):569-571
The association between an abdominal aortic aneurysm (AAA) and tuberous sclerosis (TS) is rare. An 8-month-old girl presented with a seizure, and the clinical evaluation revealed TS. An abdominal evaluation showed a 3-cm infrarenal AAA. A normal diameter of infrarenal aorta for an 8-month-old girl is about 6 mm. The patient underwent an open repair with a polytetrafluoroethylene (PTFE) prosthesis. The pathology showed a loss of elastin fibres in the media of the aorta. The graft was patent on computed tomography (CT) angiography, performed 4 months after the operation. However, the patient died of complications related to seizures 5 years after the surgery. The graft remained patent until the time of death. 相似文献
995.
Seung Gyun In Sung Hyup Han Jeong Hyun Shin Gwang Seong Choi Moon Hyun Chung 《ANNALS OF DERMATOLOGY》2008,20(2):82-85
Nocardiosis refers to a locally invasive or disseminated infection associated with the Nocardia species. Most infections enter through the respiratory tract and then disseminate systemically. Rarely can a primary nocardial infection of the skin spread to contiguous structures or disseminate to other internal organs in immunocompromised hosts. We describe a 70-year-old woman who suffered from recurrent nodular skin lesions on her right hand, forearm and elbow following inoculation of a traumatic injury. Analysis of the purulent exudates obtained from the nodule revealed Nocardia species. After 20 days, a chest X-ray showed newly developed multiple nodules in both lungs. The diagnosis of systemic nocardiosis was established, and we treated this case with trimethoprim-sulfamethoxazole. 相似文献
996.
Yongdoo Choi Chulkyu Lee Sang Yoon Kim Sun Hee Kim Hyun Tae Moon Tae Gwan Park Youngro Byun 《Drug development research》2002,57(3):134-139
Previously, poly(L‐lactide) microspheres containing retinoic acid (RA) had been prepared for parenteral administration in order to overcome “acute retinoic acid resistance.” In this study, acute toxicities of RA‐loaded microspheres were investigated in mice after the microspheres were injected intramuscularly. The maximum dose of RA in the microspheres was determined by considering both the injection volume and dispersion of microspheres in the vehicle media, and the dose levels were determined to be 0, 90, 180, and 360 mg RA/kg. Mice were carefully observed for any clinical signs for 14 days, and gross observation of the organs was performed at 14 days. When a dose of 90 mg RA/kg was administered, no severe toxicities were observed; however, with the administration of 180 and 360 mg RA/kg, abnormal appearances of organs, such as discolor, atrophy, hemorrhage, etc., were observed. There were no mortalities or bone fractures observed at any of the doses. In our previous study of cancer treatment using the RA‐loaded microspheres, the growth of head and neck carcinoma in athymic nude mice was successfully inhibited at the dose of 100 mg RA/kg. It was concluded that a dose of approximately 90 mg RA/kg of the RA‐loaded microspheres would be most desirable for cancer therapy. Drug Dev. Res. 57:134–139, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
997.
The objective of this study was to determine the shear bond strength of dental amalgam bonded to dentin with adhesives. Four groups of 15 permanent posterior teeth were used in this study. The occlusal enamel of the teeth was removed to produce a flat dentin surface. The teeth were embedded in phenolic rings with acrylic resin. Vinyl polysiloxane ring molds 4 mm thick with 4.5 mm circular openings were attached to the exposed dentin surface. Adhesives applied to the dentin surfaces prior to amalgam placement and condensation included: Amalgambond, a 4-META/TBB-MMA, HEMA based system (A), Panavia EX, a modified phosphate ester of Bis-GMA luting system (P), and Ketac-Cem, a glass ionomer luting cement (K). A dentin bonding agent and composite resin restoration system (Scotchbond 2/Silux Plus) was included for comparison. The specimens were stored in 37 degrees C water for 7 days prior to testing. Shear bond tests were done in an Instron machine at a crosshead speed of 0.02 inches per minute. The data were analyzed by ANOVA at 5% level of significance. The differences in shear bond strengths of the four test groups were not statistically significant (P = 0.115). Fracture patterns of the bonded amalgams, examined by SEM, were adhesive in appearance for Groups A and K and cohesive for Group P. 相似文献
998.
Rohin Francis Peter Kellman Tushar Kotecha Andrea Baggiano Karl Norrington Ana Martinez-Naharro Sabrina Nordin Daniel S. Knight Roby D. Rakhit Tim Lockie Philip N. Hawkins James C. Moon Derek J. Hausenloy Michael S. Hansen Marianna Fontana 《Journal of cardiovascular magnetic resonance》2017,19(1):91
Background
Conventional bright blood late gadolinium enhancement (bright blood LGE) imaging is a routine cardiovascular magnetic resonance (CMR) technique offering excellent contrast between areas of LGE and normal myocardium. However, contrast between LGE and blood is frequently poor. Dark blood LGE (DB LGE) employs an inversion recovery T2 preparation to suppress the blood pool, thereby increasing the contrast between the endocardium and blood. The objective of this study is to compare the diagnostic utility of a novel DB phase sensitive inversion recovery (PSIR) LGE CMR sequence to standard bright blood PSIR LGE.Methods
One hundred seventy-two patients referred for clinical CMR were scanned. A full left ventricle short axis stack was performed using both techniques, varying which was performed first in a 1:1 ratio. Two experienced observers analyzed all bright blood LGE and DB LGE stacks, which were randomized and anonymized. A scoring system was devised to quantify the presence and extent of gadolinium enhancement and the confidence with which the diagnosis could be made.Results
A total of 2752 LV segments were analyzed. There was very good inter-observer correlation for quantifying LGE. DB LGE analysis found 41.5% more segments that exhibited hyperenhancement in comparison to bright blood LGE (248/2752 segments (9.0%) positive for LGE with bright blood; 351/2752 segments (12.8%) positive for LGE with DB; p?<?0.05). DB LGE also allowed observers to be more confident when diagnosing LGE (bright blood LGE high confidence in 154/248 regions (62.1%); DB LGE in 275/324 (84.9%) regions (p?<?0.05)). Eighteen patients with no bright blood LGE were found to have had DB LGE, 15 of whom had no known history of myocardial infarction.Conclusions
DB LGE significantly increases LGE detection compared to standard bright blood LGE. It also increases observer confidence, particularly for subendocardial LGE, which may have important clinical implications.999.
Manoel Galvao Neto Lyz Bezerra Silva Eduardo Grecco Luiz Gustavo de Quadros André Teixeira Thiago Souza Jimi Scarparo Artur A. Parada Ricardo Dib Rena Moon Josemberg Campos 《Surgery for obesity and related diseases》2018,14(2):151-159
Background
Intragastric balloons (IGBs) are a minimally invasive option for obesity treatment, acting as a space-occupying device and leading to weight loss through increased satiety. This device has been growing in popularity owing to its safety profile and good weight loss results. However, there are no published guidelines that standardize the technical aspects of the procedure.Objectives
To create a practical guideline for intragastric balloon usage.Setting
Private and Academic Settings, Brazil.Methods
A consensus meeting was held in São Paulo, Brazil, in June 2016, bringing together 39 Brazilian endoscopists with extensive experience in IGBs from all regions of the country. Topics on patient selection, indications, contraindications, multidisciplinary follow-up, technique, and adverse events were discussed in the form of questions. After electronic voting, a consensus was defined when there was ≥70% agreement. Experts were also requested to provide data on their experience with IGBs.Results
The selected experts discussed and reached a consensus on 76 questions, mainly concerning specific indications and contraindications for the procedure; technical details, such as patient preparation, minimum balloon-filling volume, techniques for implant and explant; patient follow-up and recommended medication for the adaptation period; and adverse event management. The overall Brazilian expert data encompassed 41,863 IGBs, with a mean percentage total weight loss of 18.4% ± 2.9%. The adverse event rate after the adaptation period was 2.5%, the most common being hyperinflation (.9%) and spontaneous deflation (.8%) of the device. The early removal rate due to intolerance was 2.2%.Conclusions
The present consensus represents practical recommendations for performing IGB procedures and reflects Brazil’s significant experience with this device. The experience of over 40,000 cases shows that the device leads to satisfactory weight loss with a low rate of adverse events. 相似文献1000.
Michael Walsh MD Jon A. Jacobson MD Sung Moon Kim MD David R. Lucas MD Yoav Morag MD David P. Fessell MD 《Journal of ultrasound in medicine》2008,27(12):1751-1757
Objective. The purpose of this study was to describe the sonographic appearance of pathologically proven isolated fat necrosis involving the extremities or torso with magnetic resonance imaging (MRI) correlation. Methods. A query of the Department of Pathology database at our institution for the diagnosis of fat necrosis resulted in 1539 cases. Review of the cases and medical records excluded cases without sonographic imaging, those involving the breast, and those within or adjacent to a primary process, including masses or prior surgery, which resulted in a total of 5 cases of primary fat necrosis, 2 of which were evaluated with MRI. Sonograms were reviewed by 2 musculoskeletal radiologists and characterized with regard to location, echogenicity, shadowing, posterior through‐transmission, a hypoechoic rim or halo, definition of borders, homogeneity, a mass effect, and vascularity. The patient medical records, histologic results, and MRI findings were also reviewed. Results. Of the 5 cases of isolated fat necrosis, 2 involved the torso and 3 the lower extremities. On sonography, all were located in the subcutaneous fat; 2 were isoechoic; 3 were hyperechoic; 2 had a hypoechoic halo; none showed shadowing or posterior through‐transmission; 2 were well defined; 3 were masslike; 4 were heterogeneous; and 2 showed increased flow on color or power Doppler imaging. Magnetic resonance imaging showed an intermediate signal and either diffuse or ring enhancement. Conclusions. Isolated fat necrosis of the extremities and torso had 2 sonographic appearances, which included a well‐defined isoechoic mass with a hypoechoic halo and a poorly defined hyperechoic region in the subcutaneous fat. 相似文献