全文获取类型
收费全文 | 46898篇 |
免费 | 2853篇 |
国内免费 | 196篇 |
专业分类
耳鼻咽喉 | 623篇 |
儿科学 | 1174篇 |
妇产科学 | 956篇 |
基础医学 | 6635篇 |
口腔科学 | 4370篇 |
临床医学 | 3476篇 |
内科学 | 9739篇 |
皮肤病学 | 1029篇 |
神经病学 | 3557篇 |
特种医学 | 979篇 |
外国民族医学 | 2篇 |
外科学 | 5673篇 |
综合类 | 492篇 |
一般理论 | 10篇 |
预防医学 | 5194篇 |
眼科学 | 825篇 |
药学 | 3003篇 |
中国医学 | 419篇 |
肿瘤学 | 1791篇 |
出版年
2023年 | 376篇 |
2022年 | 851篇 |
2021年 | 1727篇 |
2020年 | 1170篇 |
2019年 | 1436篇 |
2018年 | 1727篇 |
2017年 | 1208篇 |
2016年 | 1307篇 |
2015年 | 1571篇 |
2014年 | 2102篇 |
2013年 | 2436篇 |
2012年 | 3691篇 |
2011年 | 4170篇 |
2010年 | 2154篇 |
2009年 | 1629篇 |
2008年 | 2844篇 |
2007年 | 2862篇 |
2006年 | 2525篇 |
2005年 | 2154篇 |
2004年 | 1913篇 |
2003年 | 1705篇 |
2002年 | 1496篇 |
2001年 | 787篇 |
2000年 | 813篇 |
1999年 | 652篇 |
1998年 | 264篇 |
1997年 | 181篇 |
1996年 | 164篇 |
1995年 | 155篇 |
1994年 | 139篇 |
1993年 | 120篇 |
1992年 | 303篇 |
1991年 | 284篇 |
1990年 | 273篇 |
1989年 | 260篇 |
1988年 | 230篇 |
1987年 | 180篇 |
1986年 | 180篇 |
1985年 | 171篇 |
1984年 | 137篇 |
1983年 | 111篇 |
1979年 | 116篇 |
1978年 | 98篇 |
1975年 | 78篇 |
1974年 | 89篇 |
1973年 | 98篇 |
1970年 | 96篇 |
1969年 | 98篇 |
1968年 | 78篇 |
1967年 | 87篇 |
排序方式: 共有10000条查询结果,搜索用时 281 毫秒
11.
Dalton Luiz Schiessel Ricardo K. Yamazaki Marcelo Kryczyk Isabela Coelho de Castro Adriana A. Yamaguchi Danielle C. T. Pequito 《Nutrition and cancer》2016,68(8):1369-1380
Objective: Polyunsaturated fatty acids n-3 (PUFA n-3) have shown effects in reducing tumor growth, in particular eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) abundantly present in fish oil (FO). When these fatty acids are provided in the diet, they alter the functions of the cells, particularly in tumor and immune cells. However, the effects of α-linolenic fatty acid (ALA), which is the precursor of EPA and DHA, are controversial. Thus, our objective was to test the effect of this parental fatty acid. Methods: Non-tumor-bearing and tumor-bearing Wistar rats (70 days) were supplemented with 1 g/kg body weight of FO or Oro Inca® (OI) oil (rich in ALA). Immune cells function, proliferation, cytokine production, and subpopulation profile were evaluated. Results: We have shown that innate immune cells enhanced phagocytosis capacity, and increased processing and elimination of antigens. Moreover, there was a decrease in production of pro-inflammatory cytokines (tumor necrosis factor-alpha (TNF-α) and interleukin 6 (IL-6)) by macrophages. Lymphocytes showed decreased proliferation capacity, increased cluster of differentiation 8 (CD8+) subpopulation, and increased TNF-α production. Conclusions: Oil rich in ALA caused similar immune modulation in cancer when compared with FO. 相似文献
12.
Ignasi Esteban Carmen Pastor-Quiones Lorena Usero Montserrat Plana Felipe García Lorna Leal 《Viruses》2021,13(3)
Over 36 million people worldwide are infected with HIV. Antiretroviral therapy (ART) has proven to be highly effective to prevent HIV-1 transmission, clinical progression and death. Despite this success, the number of HIV-1 infected individuals continues increasing and ART should be taken for life. Therefore, there are two main priorities: the development of preventive vaccines to protect from HIV acquisition and achieve an efficient control of HIV infection in the absence of ART (functional cure). In this sense, in the last few years, there has been a broad interest in new and innovative approaches such as mRNA-based vaccines. RNA-based immunogens represent a promising alternative to conventional vaccines because of their high potency, capacity for rapid development and potential for low-cost manufacture and safe administration. Some mRNA-based vaccines platforms against infectious diseases have demonstrated encouraging results in animal models and humans. However, their application is still limited because the instability and inefficient in vivo delivery of mRNA. Immunogens, design, immunogenicity, chemical modifications on the molecule or the vaccine delivery methods are all crucial interventions for improvement. In this review we, will present the current knowledge and challenges in this research field. mRNA vaccines hold great promises as part of a combined strategy, for achieving HIV functional cure. 相似文献
13.
14.
Iclea Rocha Gama Euclides Marinho Trindade-Filho Suzana Lima Oliveira Nassib Bezerra Bueno Isabelle Tenório Melo Cyro Rego Cabral-Junior Elenita M. Barros Jaqueline A. Galvão Wanessa S. Pereira Raphaela C. Ferreira Bruna R. Domingos Terezinha da Rocha Ataide 《Metabolic brain disease》2015,30(1):93-98
15.
16.
17.
Die Anaesthesiologie - Simulationstraining ist für die Notfallmedizin unverzichtbar, insbesondere in Hinsicht auf eine verbesserte Patientensicherheit. Methoden und Technologien umfassen ein... 相似文献
18.
19.
Willy Baccaglini Felipe A. Glina Cristiano Linck Pazeto Luis G. Medina Fernando Korkes Wanderley M. Bernardo Rene Sotelo Sidney Glina Giancarlo Marra Marco Moschini Xavier Cathelineau Rafael Sanchez-Salas 《Clinical genitourinary cancer》2021,19(1):3-11.e1
This meta-analysis focuses on the accuracy of upgrading to clinically significant prostate cancer (PCa) by multiparametric magnetic resonance imaging-targeted biopsy (MRI-TB) versus systematic biopsy (SB). We searched the Medline, Embase, Cochrane Central Register of Controlled Trials, Web of Science, Scopus, and Literatura Latino Americana em Ciências da Saúde databases through January 2020 for comparative, retrospective/prospective, paired-cohort, and randomized clinical trials with paired comparisons. The population consisted of patients with low-risk PCa in active surveillance with at least 1 index lesion on imaging. We evaluated the quality of evidence by using the Quality Assessment of Diagnostic Accuracy Studies-2 score. Group comparisons considered the differences between the area under the curve summary receiver operating characteristic curve in a 2-tailed method. We also compared the positive predictive value of the best single method (MRI-TB or SB) and the referral study test (combined biopsy, a combination of MRI-TB and SB). The meta-analysis included 6 studies enrolling 741 patients. The pooled sensitivity for the 2 groups was 0.79 (95% confidence interval, 0.74-0.83; I2 = 75%) and 0.67 (95% confidence interval, 0.63-0.74; I2 = 55.4%), respectively. The area under the curve for the MRI-TB and SB groups were 0.99 and 0.92 (P < .001), respectively. The positive predictive value for the MRI-TB and combined biopsy groups were similar. The accumulated evidence suggests better results for MRI-TB compared with SB. Therefore, use of MRI-TB alone may be preferable in patients in active surveillance harboring low-risk PCa. 相似文献
20.
Del Lama Rafael Silva Candido Raquel Mariana Chiari-Correia Natália Santana Nogueira-Barbosa Marcello Henrique de Azevedo-Marques Paulo Mazzoncini Tinós Renato 《Journal of digital imaging》2022,35(3):446-458
Journal of Digital Imaging - Vertebral Compression Fracture (VCF) occurs when the vertebral body partially collapses under the action of compressive forces. Non-traumatic VCFs can be secondary to... 相似文献