全文获取类型
收费全文 | 5093篇 |
免费 | 319篇 |
国内免费 | 82篇 |
专业分类
耳鼻咽喉 | 87篇 |
儿科学 | 149篇 |
妇产科学 | 116篇 |
基础医学 | 548篇 |
口腔科学 | 618篇 |
临床医学 | 361篇 |
内科学 | 1095篇 |
皮肤病学 | 133篇 |
神经病学 | 286篇 |
特种医学 | 354篇 |
外科学 | 663篇 |
综合类 | 30篇 |
一般理论 | 2篇 |
预防医学 | 459篇 |
眼科学 | 132篇 |
药学 | 279篇 |
中国医学 | 64篇 |
肿瘤学 | 118篇 |
出版年
2022年 | 48篇 |
2021年 | 105篇 |
2020年 | 69篇 |
2019年 | 106篇 |
2018年 | 156篇 |
2017年 | 123篇 |
2016年 | 121篇 |
2015年 | 146篇 |
2014年 | 200篇 |
2013年 | 243篇 |
2012年 | 271篇 |
2011年 | 309篇 |
2010年 | 189篇 |
2009年 | 187篇 |
2008年 | 255篇 |
2007年 | 354篇 |
2006年 | 266篇 |
2005年 | 265篇 |
2004年 | 201篇 |
2003年 | 156篇 |
2002年 | 152篇 |
2001年 | 131篇 |
2000年 | 117篇 |
1999年 | 86篇 |
1998年 | 101篇 |
1997年 | 97篇 |
1996年 | 70篇 |
1995年 | 75篇 |
1994年 | 48篇 |
1993年 | 48篇 |
1992年 | 45篇 |
1991年 | 63篇 |
1990年 | 36篇 |
1989年 | 50篇 |
1988年 | 52篇 |
1987年 | 42篇 |
1986年 | 49篇 |
1985年 | 65篇 |
1984年 | 34篇 |
1983年 | 25篇 |
1982年 | 27篇 |
1981年 | 22篇 |
1980年 | 34篇 |
1979年 | 18篇 |
1977年 | 24篇 |
1976年 | 22篇 |
1975年 | 18篇 |
1970年 | 22篇 |
1969年 | 27篇 |
1967年 | 20篇 |
排序方式: 共有5494条查询结果,搜索用时 15 毫秒
81.
Fernanda Neves de Carvalho Carolina Toniolo Zenatti Danila Cassia Reis Santana Juliana Maria da Silva Juliane Cristina Oliveira dos As Katia Kisielow dos Anjos Jessica Sigari Cassia de Lima Santos Marcelle Guerra Olivia Pereira Barros Tomaz Cochemore Roberto Camargo Narciso Mario Lucio Baptista Filho 《The Brazilian journal of infectious diseases》2018
82.
A. Martins‐Filho M. P. Jammal D. C. Micheli B. M. Tavares‐Murta R. M. Etchebehere E. F. C. Murta R. S. Nomelini 《Scandinavian journal of immunology》2017,86(6):462-470
The development of new biomarkers for the diagnosis and prognosis of ovarian cancer may provide an opportunity for new therapies. In this study, we aimed to compare cytokines (interleukin [IL]‐2, IL‐5, IL‐6, IL‐8, IL‐10 and tumour necrosis factor [TNF]‐α) and nitric oxide (NO) metabolite levels in non‐neoplastic tumours, benign primary ovarian tumours and malignant primary ovarian neoplasms. The secondary aim was to relate cytokine and intracystic NO metabolite levels to clinical, laboratory and pathologic characteristics for patients with primary ovarian malignancies. We evaluated 110 patients with adnexal masses. Cytokine concentrations were quantified by enzyme‐linked immunosorbent assay and nitrate concentrations by enzymatic reduction of nitrite by nitrate reductase. Patients with malignant neoplasms had higher IL‐6, IL‐8 and NO levels compared to patients with benign neoplasms. Histologic grade 1 tumours were associated with elevated IL‐2 levels, whereas anaemia was associated with elevated IL‐6 levels. On average, those patients with elevated IL‐8 levels also had a neutrophil/lymphocyte ratio (NLR) greater than 2.6 and less than 36 months of disease‐free survival (DFS). Patients with normal CA 19‐9 levels had elevated IL‐10 levels. TNF‐α was elevated in patients with two carcinogenesis and those with a platelet/lymphocyte ratio (PLR) less than 300. NO levels were higher in patients with an NLR less than 2.6 and CA 19‐9 greater than 35 U/ml. Elevated intracystic cytokine levels, especially IL‐6 and IL‐8, are associated with worse prognosis in ovarian cancer. 相似文献
83.
84.
Jayme de Oliveira Filho Ana Carolina Franco Tebet Anna Rita Ferrante Mitidieri de Oliveira Kassila Nasser 《Anais brasileiros de dermatologia》2014,89(3):501-503
Ewing sarcoma is a primitive neuroectodermal tumor rarely occurs in the skin and
sobcutaneous tissues. Generally Ewing''s sarcoma is a primary bone tumor, but
when present in soft tissues it characterizes an extremely uncommon clinical
picture. It usually involves the deep subcutaneous tissue or muscles, and more
rarely occurs like a primary skin cancer. Most patients are white, women, and in
the second decade of life. The clinical features are a superficial mass, in
average measuring 2-3 cm, of soft consistency, freely mobile and sometimes
painful. The more affected locations are upper and lower extremities, trunk,
head, neck or multiple lesions. The presence of metastases is very rare. 相似文献
85.
Carolina Degen Meotti Glaura Plates Letycia Lopes Chagas Nogueira Renata Anselme da Silva Karoline Silva Paolini Elias Moreira Nunes Fred Bernardes Filho 《Anais brasileiros de dermatologia》2014,89(2):332-333
Cutaneous larva migrans is a pruritic dermatitis due to the inoculation of helminths
larvae in the skin, and it often occurs in children in tropical and subtropical
areas. The authors describe an atypical case of cutaneous larva migrans in a 11
year-old child with scalp involvement, an unusual topography for this lesion. 相似文献
86.
87.
Prevalence of Sjögren's syndrome in Brazilian patients infected with human T‐cell lymphotropic virus
88.
José Robson Neves Cavalcanti Filho Tiago Fonseca Silva Woah Queiroz Nobre Larissa Isabela Oliveira de Souza Cristiane Santos Silva e Silva Figueiredo Regina Celia Bressan Queiroz de Figueiredo 《Pharmaceutical biology》2017,55(1):1521-1527
Context: Buchenavia tetraphylla (Aubl.) RA Howard (Combretaceae: Combretoideae) is an ethnomedicinal plant with reported antifungal action.Objective: This study evaluates the antimicrobial activity of B. tetraphylla leaf extracts against clinical isolates of Candida albicans. The morphological alterations, combinatory effects with fluconazole and the cytotoxicity of the active extract were analyzed.Materials and methods: Extracts were obtained using different solvents (hexane: BTHE; chloroform: BTCE; ethyl acetate: BTEE; and methanol: BTME). Antimicrobial activity was determined by the broth microdilution method using nine strains of C. albicans isolated from vaginal secretions and one standard strain (UFPEDA 1007).Results: All extracts showed anti-C. albicans activity, including against the azole-resistant strains. The MIC values ranged from 156 to 2500?μg/mL for the BTHE; 156 to 1250?μg/mL for the BTCE; 625 to 1250?μg/mL for the BTME and 625?μg/mL to 2500?μg/mL for the BTEE. BTME showed the best anti-C. albicans activity. This extract demonstrated additive/synergistic interactions with fluconazole. Scanning electron microscopy analysis suggested that the BTME interferes with the cell division and development of C. albicans. BTME showed IC50 values of 981 and 3935?μg/mL, against J774 macrophages and human erythrocytes, respectively. This extract also enhanced the production of nitric oxide by J774 macrophages.Discussion and conclusion: Buchenavia tetraphylla methanolic extract (BTME) is a great source of antimicrobial compounds that are able to enhance the action of fluconazole against different C. albicans strains; this action seems related to inhibition of cell division. 相似文献
89.
90.
Antônio P. R. Filho Camila B. do Nascimento Luciana P. G. d’Arce 《International journal of environmental health research》2018,28(1):1-7
Gas station attendants are potentially exposed to carcinogenic substances. This study aimed to evaluate chronic occupational exposed gas station attendant’s according to genetic parameters and its relationship with cancer predisposition. Forty gas station attendants were recruited and paired with 40 control subjects. Thousand cells from each subject were analyzed counting the number of pyknotic (PYC), karyolitic (KYL), karyorrhetic (KHC), condensed chromatin (CC), binucleated (BN), basal cells (BC), Nuclear buds (Nbud), and differentiated cells (DIFF). More 2.000 differentiated cells were analyzed counting micronucleated (MNi) and nuclear buds (NBud). We observed a statistical increase in BC and decrease in DIFF (p < 0.05). PYC, CC, KYL, MN, NBud were statistically increased (p < 0.05). All in all, our data showed elevated DNA damage, chromosomal instability, and cell cycle disturbing in our group of gas station attendants. It is a clear risk for their health in future and could be classified as a cancer predisposition. 相似文献