全文获取类型
收费全文 | 105291篇 |
免费 | 11224篇 |
国内免费 | 3256篇 |
专业分类
耳鼻咽喉 | 750篇 |
儿科学 | 1638篇 |
妇产科学 | 1217篇 |
基础医学 | 20058篇 |
口腔科学 | 2791篇 |
临床医学 | 6605篇 |
内科学 | 15462篇 |
皮肤病学 | 1914篇 |
神经病学 | 11447篇 |
特种医学 | 2857篇 |
外国民族医学 | 27篇 |
外科学 | 8415篇 |
综合类 | 10407篇 |
现状与发展 | 14篇 |
预防医学 | 4155篇 |
眼科学 | 1065篇 |
药学 | 17086篇 |
33篇 | |
中国医学 | 4033篇 |
肿瘤学 | 9797篇 |
出版年
2024年 | 190篇 |
2023年 | 1786篇 |
2022年 | 2445篇 |
2021年 | 4918篇 |
2020年 | 4149篇 |
2019年 | 4436篇 |
2018年 | 4265篇 |
2017年 | 4202篇 |
2016年 | 3931篇 |
2015年 | 4453篇 |
2014年 | 6465篇 |
2013年 | 6722篇 |
2012年 | 5940篇 |
2011年 | 7096篇 |
2010年 | 5696篇 |
2009年 | 5704篇 |
2008年 | 5638篇 |
2007年 | 4796篇 |
2006年 | 4111篇 |
2005年 | 3805篇 |
2004年 | 3210篇 |
2003年 | 2851篇 |
2002年 | 2136篇 |
2001年 | 1806篇 |
2000年 | 1513篇 |
1999年 | 1411篇 |
1998年 | 1355篇 |
1997年 | 1319篇 |
1996年 | 1212篇 |
1995年 | 1110篇 |
1994年 | 1024篇 |
1993年 | 969篇 |
1992年 | 761篇 |
1991年 | 686篇 |
1990年 | 587篇 |
1989年 | 498篇 |
1988年 | 474篇 |
1987年 | 475篇 |
1986年 | 572篇 |
1985年 | 787篇 |
1984年 | 747篇 |
1983年 | 586篇 |
1982年 | 586篇 |
1981年 | 491篇 |
1980年 | 454篇 |
1979年 | 378篇 |
1978年 | 230篇 |
1977年 | 192篇 |
1976年 | 200篇 |
1975年 | 121篇 |
排序方式: 共有10000条查询结果,搜索用时 86 毫秒
111.
112.
《Arquivos brasileiros de cardiologia》2020,115(2):207
BackgroundTakotsubo syndrome (TTS) is an acquired form of cardiomyopathy. National Brazilian data on this condition are scarce. The Takotsubo Multicenter Registry (REMUTA) is the first to include multicenter data on this condition in Brazil.ObjectiveTo describe the clinical characteristics, prognosis, in-hospital treatment, in-hospital mortality, and mortality during 1 year of follow-up.MethodsThis is an observational, retrospective registry study including patients admitted to the hospital with diagnosis of TTS and patients admitted for other reasons who developed this condition. Evaluated outcomes included triggering factor, analysis of exams, use of medications, complications, in-hospital mortality, and mortality during 1 year of follow-up. A significance level of 5% was adopted.ResultsThe registry included 169 patients from 12 centers in the state of Rio de Janeiro, Brazil. Mean age was 70.9 ± 14.1 years, and 90.5% of patients were female; 63% of cases were primary TTS, and 37% were secondary. Troponin I was positive in 92.5% of patients, and median BNP was 395 (176.5; 1725). ST-segment elevation was present in 28% of patients. Median left ventricular ejection fraction was 40 (35; 48)%. We observed invasive mechanical ventilation in 25.7% of cases and shock in 17.4%. Mechanical circulatory support was used in 7.7%. In-hospital mortality was 10.6%, and mortality at 1 year of follow-up was 16.5%. Secondary TTS and cardiogenic shock were independent predictors of mortality.ConclusionThe results of the REMUTA show that TTS is not a benign pathology, as was once thought, especially regarding the secondary TTS group, which has a high rate of complications and mortality. (Arq Bras Cardiol. 2020; 115(2):207-216) 相似文献
113.
Sumanta K. Pal MD Dean Bajorin MD Nazli Dizman MD Jean Hoffman-Censits MD David I. Quinn MD Daniel P. Petrylak MD Matthew D. Galsky MD Ulka Vaishampayan MD Ugo De Giorgi MD Sumati Gupta MD Howard A. Burris MD Harris S. Soifer PhD Gary Li PhD Hao Wang PhD Carl L. Dambkowski MD Susan Moran MD Siamak Daneshmand MD Jonathan E. Rosenberg MD 《Cancer》2020,126(11):2597-2606
114.
《Journal of Clinical Orthopaedics and Trauma》2019,10(2):380-386
Additive manufacturing is a rapidly emerging technology which is being successfully implemented in the various field of medicine as well as in orthopaedics, where it has applications in reducing cartilage defects and treatments of bones. The technology helps through systematic collection of information about the shape of the "defects" and precise fabrication of complex 3D constructs such as cartilage, heart valve, trachea, myocardial bone tissue and blood vessels. In this paper, a large number of the relevant research papers on the additive manufacturing and its application in medical specifically orthopaedics are identified through Scopus had been studied using Bibliometric analysis and application analysis is undertaken. The bibliometric analysis shows that there is an increasing trend in the research reports on additive manufacturing applications in the field of orthopaedics. Discussions are on using technological advancement like scanning techniques and various challenges of the orthopaedic being met by additive manufacturing technology. For patient-specific orthopaedic applications, these techniques incorporate clinical practice and use for effective planning. 3D printed models printed by this technology are accepted for orthopaedic surgery such as revision of lumbar discectomy, pelvic surgery and large scapular osteochondroma. The applications of additive manufacturing in orthopaedics will experience a rapid translation in future. An orthopaedic surgeon can convert need/idea into a reality by using computer-aided design (CAD) software, analysis software to facilitate the manufacturing. Thus, AM provides a comprehensive opportunity to manufacture orthopaedic implantable medical devices. 相似文献
115.
《Clinical Lymphoma, Myeloma & Leukemia》2020,20(7):459-467
BackgroundCore binding factor acute myeloid leukemia (CBF-AML) encodes 2 recurrent cytogenetic abnormalities, t(8;21) and inv(16), which carries an overall good prognosis. However, some patients will develop a relapse. We sought define the unfavorable group of CBF-AML by analysis of (c-KIT and FLT3-ITD) and to correlate them with treatment outcome.Patients and MethodsWe performed a prospective study of 70 patients with CBF-AML diagnosed and managed at the medical oncology department of the (National Cancer Institute), Cairo University, with analysis of c-KIT and FLT3 mutations. All patients had received “3 + 7” induction, followed by 3 to 4 courses of high-dose cytarabine consolidation. The institutional review board approved the present study.ResultsThe median patient age was 31 years (range, 18-60 years), with a male/female ratio of 4:3. Of the 70 patients, 42 (60%) had t(8;21) and 28 had inv(16) (40%). c-KIT mutations (exons 8 and 17) were detected in 10 of 52 tested patients, and FLT3-ITD was detected in 3 of 70 patients. Patients with inv(16) experienced more lymphadenopathy and splenomegaly, had a higher median initial leukocyte count. Hepatitis C antibody positivity (8 of 42) was exclusively present in patients with t(8;21). The median overall survival (OS) was 19.5 months, and the median disease-free survival (DFS) was not reached. Patients with inv(16) had near-significant (P = .07) better DFS than patients with t(8;21). c-KIT mutations had no significant effect on OS or DFS. However, reverse tyrosine kinase mutations had a negative effect on DFS but not OS (P = .04).ConclusionCBF-AML with reverse tyrosine kinase mutation conveys a worse prognosis. Hepatitis C virus antibody positivity might be associated with t(8;21) AML and inv(16) with more extramedullary disease. 相似文献
116.
Consensus on the use and monitoring of anti‐TNF‐α therapies for rheumatic diseases in Hong Kong 2005
《International journal of rheumatic diseases》2006,9(2):175-180
The development and use of the tumour necrosis factor (TNF) antagonists is a major breakthrough in the treatment of many rheumatic diseases. Although these novel agents are undoubtedly superior to conventional therapeutic modalities, their costs and potential adverse effects are of concern. The current consensus statements were developed in early 2005 to help practicing rheumatologists identify which adult patients may benefit from anti‐TNF therapies and highlight their potential toxicities. The Hong Kong Society of Rheumatology has developed a registry on the use of the biologics in our local patients with chronic rheumatic disorders. Because the indications and novel data regarding the TNF inhibitors are ever changing, this consensus will be updated regularly. 相似文献
117.
A method is presented for 3D MRI in an extended field of view (FOV) based on continuous motion of the patient table and an efficient acquisition scheme. A gradient-echo MR pulse sequence is applied with lateral (left-right (L/R)) frequency-encoding direction and slab selection along the direction of motion. Compensation for the table motion is achieved by a combination of slab tracking and data alignment in hybrid space. The method allows fast k-space coverage to be achieved, especially when a short sampling FOV is chosen along the direction of table motion, as is desirable for good image quality. The method can be incorporated into different acquisitions schemes, including segmented k-space scanning, which allows for contrast variation with the use of magnetization preparation. Head-to-toe images of volunteers were obtained with good quality using 3D spoiled gradient-echo sequences. As an example of magnetization-prepared imaging, fat/water separated images were acquired using chemical shift selective (CHESS) presaturation pulses. 相似文献
118.
皮质发育障碍模型的建立及其致痫敏感性的研究 总被引:1,自引:0,他引:1
目的:建立皮质发育障碍模型,探讨皮质发育障碍模型的敏感性。方法:在SD大鼠孕17d腹腔注入1,3-二氯乙烯-亚硝基脲(BCNU)制作皮质发育障碍模型;Nissl染色观察P60d仔鼠病理变化;选取P60d雄性仔鼠,腹腔注射氯化锂-毛果芸香碱,分别比较两组大鼠癫发生的潜伏期、持续状态时间和死亡率。结果:同龄仔鼠脑组织湿重实验组比对照组显著减轻(P<0.01);Nissl染色显示皮质变薄、皮质层次紊乱、海马区域异位细胞异常聚集;有皮质发育障碍的仔鼠注射氯化锂-毛果芸香碱后,癫发生的潜伏期显著缩短(P<0.01),癫持续状态时间延长(P<0.01),死亡率显著升高(P<0.05)。结论:BCNU致皮质发育障碍模型具有癫易感性。 相似文献
119.
120.
海水浸泡兔脑挫伤后caspase-8及caspase-3表达的研究 总被引:2,自引:0,他引:2
目的建立海水浸泡颅脑挫裂伤模型,观察海水浸泡对实验性脑挫裂伤后创伤性脑水肿的影响及研究兔脑挫伤后不同时间caspase-8及caspase-3表达的变化。方法采用立体定向自由落体伤模型进行持续海水浸泡作为实验组,对照组采用同样的方法致伤后不进行海水浸泡。观察创伤组织的病理改变,并通过免疫组化染色和计算机图像分析技术用半定量化的方法检测不同干预不同时程caspase-8和caspase-3的活性表达强弱差异。结果实验组和对照组均发生了创伤性脑水肿,但水肿高峰期出现时间不一致,严重程度也不一致。实验组caspase-8和caspase-3活性表达强度均高于对照组。结论海水浸泡促进了挫裂伤周边缺血水肿区神经细胞凋亡的增加。 相似文献