全文获取类型
收费全文 | 3672篇 |
免费 | 206篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 53篇 |
儿科学 | 128篇 |
妇产科学 | 122篇 |
基础医学 | 431篇 |
口腔科学 | 288篇 |
临床医学 | 239篇 |
内科学 | 692篇 |
皮肤病学 | 70篇 |
神经病学 | 223篇 |
特种医学 | 102篇 |
外科学 | 442篇 |
综合类 | 21篇 |
一般理论 | 1篇 |
预防医学 | 600篇 |
眼科学 | 58篇 |
药学 | 277篇 |
中国医学 | 33篇 |
肿瘤学 | 104篇 |
出版年
2023年 | 29篇 |
2022年 | 97篇 |
2021年 | 125篇 |
2020年 | 83篇 |
2019年 | 113篇 |
2018年 | 127篇 |
2017年 | 79篇 |
2016年 | 102篇 |
2015年 | 115篇 |
2014年 | 169篇 |
2013年 | 156篇 |
2012年 | 251篇 |
2011年 | 268篇 |
2010年 | 177篇 |
2009年 | 111篇 |
2008年 | 215篇 |
2007年 | 211篇 |
2006年 | 178篇 |
2005年 | 160篇 |
2004年 | 139篇 |
2003年 | 130篇 |
2002年 | 89篇 |
2001年 | 104篇 |
2000年 | 80篇 |
1999年 | 75篇 |
1998年 | 25篇 |
1997年 | 29篇 |
1996年 | 32篇 |
1995年 | 27篇 |
1994年 | 14篇 |
1993年 | 16篇 |
1992年 | 33篇 |
1991年 | 28篇 |
1990年 | 37篇 |
1989年 | 26篇 |
1988年 | 24篇 |
1987年 | 35篇 |
1986年 | 24篇 |
1985年 | 23篇 |
1984年 | 16篇 |
1979年 | 10篇 |
1978年 | 15篇 |
1977年 | 6篇 |
1975年 | 6篇 |
1971年 | 5篇 |
1970年 | 9篇 |
1969年 | 6篇 |
1968年 | 6篇 |
1967年 | 8篇 |
1965年 | 5篇 |
排序方式: 共有3884条查询结果,搜索用时 15 毫秒
91.
92.
Peres KG De Oliveira Latorre Mdo R Sheiham A Peres MA Victora CG Barros FC 《International journal of paediatric dentistry / the British Paedodontic Society [and] the International Association of Dentistry for Children》2007,17(1):41-49
OBJECTIVE: Little is known about the effects of social and biological risk factors for open bite on the primary dentition. The aim of this study was to assess the early-life risk factors affecting anterior open bite. METHODS: A cross-sectional study using a birth cohort was carried out in Pelotas, Brazil. A sample of 400, 6-year-old children was employed. The Foster and Hamilton criteria were used to classify open bite. Data concerning social conditions, and perinatal and childhood health and behaviour were obtained from birth to 12 months of age and during the fifth year of the children's lives. Unconditional bivariate and multiple logistic regression analysis were performed. RESULTS: The prevalence of anterior open bite was 46.3%. Risk factors included: a maternal age of between 30 and 39 years, as compared with children whose mothers were younger; breast-feeding for < 9 months; dental caries experience; pacifier sucking between 12 months and 5 years, as compared to no sucking or a shorter duration of sucking; and the presence of finger-sucking at 6 years of age. CONCLUSION: Open bite in the primary dentition was associated with older mothers, early weaning, dental caries occurrence, long-term use of a pacifier and finger-sucking at 6 years of age. These findings support the common risk approach for intervention to prevent open bite in the primary dentition. 相似文献
93.
Carneiro Alexandra Melo Pingarilho Barros Antonia Patrícia Oliveira de Oliveira Roberta Pimentel de Paula Brennda Lucy Freitas Silva Aryvelto Miranda de Melo Alencar Cristiane Silva Cecy Martins 《Lasers in medical science》2022,37(7):2791-2804
Lasers in Medical Science - The authors aimed to conduct a systematic review to assess data from the current literature on the effectiveness of low-level laser therapy (LLLT) in preventing tooth... 相似文献
94.
95.
Ana Cludia Philippus Gabriele A. Zatelli Tauana Wanke Maria Gabriela de A. Barros Satomy A. Kami Cintia Lhullier Lorene Armstrong Louis P. Sandjo Miriam Falkenberg 《RSC advances》2018,8(52):29654
Molecular networking (MN) can efficiently dereplicate extracts and pure compounds. Red algae of the genus Laurencia are rich in halogenated secondary metabolites, mainly sesquiterpenes and C15-acetogenins. Brown algae of the genus Dictyopteris produce mainly C11-hydrocarbons, sesquiterpenes and sulfur-containing compounds, while Dictyota and Canistrocarpus are reported to contain mainly diterpenes. This study performs an exploratory MN analysis of 14 extracts from algae collected in Brazil (including the oceanic islands) and characterizes the secondary metabolites from the analyzed species. The extracts and some isolated metabolites were analyzed by LC-MS using the FastDDA algorithm, and the MS/MS spectra were submitted to GNPS and displayed in Cytoscape 3.5.1. The GNPS platform generated 68 individual nodes and nine family networks. The MN exploratory analysis indicated chemical differences among species, and also in sampling sites for the same species. For some extracts, it was possible to identify mass values that could correspond to terpenoids and C15-acetogenins that have already been isolated from those or related species. An interesting chemodiversity was highlighted between Laurencia catarinensis from two nearby islands, and this was revealed and was also suggested by the family networks. Many nodes in the MN could not be characterized, and these metabolites can be used as targets for isolation in future works.Molecular networking of Brazilian marine algae. 相似文献
96.
Danijela Stanisic Natlia L. Fregonesi Caio H. N. Barros Joo G. M. Pontes Stephanie Fulaz Ulisses J. Menezes Jorge L. Nicoleti Thiago L. P. Castro Núbia Seyffert Vasco Azevedo Nelson Durn Ricardo W. Portela Ljubica Tasic 《RSC advances》2018,8(71):40778
Caseous lymphadenitis (CL), caused by a pathogen of the second class of biosafety – Corynebacterium pseudotuberculosis, is a chronic and severe infectious disease that affects small ruminants and requires long, ineffective treatment which generally leads to animal sacrifice so as to stop the disease spreading. The infected animals suffer the excision of affected superficial lymph nodes and post-surgical treatment with iodine (10% solution in ethanol) and, sometimes, prolonged antibiotic use, but only if the sick animals are of great importance to breeding. Herein, we propose a cheap and easy to apply treatment of CL with excellent results using biogenic silver nanoparticles (AgNP) based technology. AgNP antibacterial properties were investigated in vitro against Corynebacterium pseudotuberculosis cells and in vivo on small ruminants with CL. Treatment of surgical wounds resulting from the excision of superficial CL lesions with a AgNP-based cream was compared to the standard post-surgical treatment method by iodine. Also, the effects of AgNP-based cream treatment were evaluated and compared with the effects of the iodine CL treatment by serum NMR-based metabolomics. Serum samples were collected from 29 animals, 9 sheep and 20 goats, during the treatments and analyzed. All animals showed stable serum metabolomes when iodine or AgNP-based cream effects were compared. The AgNP-based cream treatment showed excellent results, especially in accelerating the healing of wounds, which occurred two to three times faster in comparison with the iodine treatment. AgNP-based cream treatment also prevented CL reappearance and did not cause any side effects on animals. This is the first report on very effective post-surgical treatment of superficial CL in small ruminants based on biogenic silver nanoparticles, which might open up the possibility for a safe veterinary application of AgNP-based cream.Biogenic nanosilver in a pharmaceutical cream for wound healing in animal and human healthcare. 相似文献
97.
Heloise Ribeiro de Barros Mateus Borba Cardoso Carolina Camargo de Oliveira Clia Regina Cavichiolo Franco Daniel de Lima Bellan Marcio Vidotti Izabel C. Riegel-Vidotti 《RSC advances》2018,8(71):40596
Correction for ‘Stability of gum Arabic-gold nanoparticles in physiological simulated pHs and their selective effect on cell lines’ by Heloise Ribeiro de Barros et al., RSC Adv., 2016, 6, 9411–9420.The authors regret that the name of one of the authors (Daniel de Lima Bellan) was shown incorrectly in the original article. The corrected author list is as shown above.The Royal Society of Chemistry apologises for these errors and any consequent inconvenience to authors and readers. 相似文献
98.
Varioliform gastritis is currently recognized as a special kind of chronic gastritis characterized by nodules, thickened fugal folds and erosions. These features appear to be unusual and different from those seen in chronic gastritis. The frequency of varioliform gastritis rarely exceeds 3% and the diagnosis can be easily made by endoscopic examination. Very little is known about the etiopathogeny, clinical significance and evolution of this disease. The role of Helicobacter pylori still remains unknown, although a close relationship between this gastritis and lymphocytic gastritis was suggested to exist over the last few years. The aim of the present study was to investigate the frequency of varioliform gastritis and its possible correlation with lymphocytic gastritis. To our knowledge, this is the first systematic study of varioliform gastritis in South America. We studied endoscopically 200 consecutive patients and found only one case of varioliform gastritis (0.5%). In a second part of the study, we examined histopathologically mucosa biopsies from 24 patients with varioliform gastritis and studied the presence of intraepithelial lymphocytes to verify the presence of lymphocytic gastritis. No case was found. We conclude that there was no correlation between varioliform gastritis and lymphocytic gastritis in our patients. 相似文献
99.
100.