全文获取类型
收费全文 | 11009篇 |
免费 | 686篇 |
国内免费 | 53篇 |
专业分类
耳鼻咽喉 | 302篇 |
儿科学 | 273篇 |
妇产科学 | 299篇 |
基础医学 | 1552篇 |
口腔科学 | 419篇 |
临床医学 | 907篇 |
内科学 | 2570篇 |
皮肤病学 | 202篇 |
神经病学 | 1252篇 |
特种医学 | 220篇 |
外科学 | 1003篇 |
综合类 | 21篇 |
一般理论 | 5篇 |
预防医学 | 644篇 |
眼科学 | 132篇 |
药学 | 689篇 |
中国医学 | 36篇 |
肿瘤学 | 1222篇 |
出版年
2024年 | 19篇 |
2023年 | 116篇 |
2022年 | 274篇 |
2021年 | 420篇 |
2020年 | 267篇 |
2019年 | 316篇 |
2018年 | 349篇 |
2017年 | 288篇 |
2016年 | 347篇 |
2015年 | 369篇 |
2014年 | 494篇 |
2013年 | 601篇 |
2012年 | 924篇 |
2011年 | 1036篇 |
2010年 | 513篇 |
2009年 | 448篇 |
2008年 | 782篇 |
2007年 | 712篇 |
2006年 | 639篇 |
2005年 | 666篇 |
2004年 | 599篇 |
2003年 | 545篇 |
2002年 | 478篇 |
2001年 | 55篇 |
2000年 | 33篇 |
1999年 | 50篇 |
1998年 | 86篇 |
1997年 | 59篇 |
1996年 | 43篇 |
1995年 | 46篇 |
1994年 | 33篇 |
1993年 | 32篇 |
1992年 | 19篇 |
1991年 | 10篇 |
1990年 | 8篇 |
1989年 | 12篇 |
1988年 | 7篇 |
1987年 | 2篇 |
1986年 | 15篇 |
1985年 | 3篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 5篇 |
1980年 | 4篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 3篇 |
1974年 | 2篇 |
1973年 | 2篇 |
1968年 | 1篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
141.
142.
5D CNS+ Software for Automatically Imaging Axial,Sagittal, and Coronal Planes of Normal and Abnormal Second‐Trimester Fetal Brains 下载免费PDF全文
143.
Phylogenetic and mathematical analyses for investigating putative mother-to-infant transmission chains when only GB virus C (hepatitis G virus) 5' noncoding region sequences are available 下载免费PDF全文
144.
145.
146.
Rocha Gomes Torres C Borges AB Torres LM Gomes IS de Oliveira RS 《Journal of dentistry》2011,39(3):202-207
Objectives
A carious lesion is initiated through the subsurface demineralization of enamel, and presents clinically as a white spot, interfering with the aesthetics. This lesion should not receive restorative treatment because it is capable of remineralization. The aim of this study was to evaluate the performance of different treatments on masking white spot lesions by assessing the colour change.Methods
Artificial white spot lesions were produced in bovine enamel of 60 cylindrical-shaped samples. The samples were randomly divided into four groups: CON (control) - immersion in artificial saliva; DF - daily application of 0.05% fluoride solution; WF - weekly application of 2% fluoride gel; and IC - resin infiltration (Icon® - DMG). The assessment of colour was performed by a spectrophotometer in four distinct stages: baseline, after the production of artificial caries; after 4 weeks; after 8 weeks; and after a new acid challenge. The ΔL values were calculated at each stage in relation to the baseline colour.Results
The application of RM ANOVA revealed significant differences between the factors’ treatment and time (p = 0.001). For the interaction between factors there were no significant differences (p = 0.27). The Tukey's test (p < 0.05) was then applied and showed that the specimens treated with Icon® exhibited the lowest means, followed by Group DF, Group CON, and Group WF, in that order.Conclusion
Resin infiltration was proven to be an effective treatment for masking white spot lesions. Also, after a new acid challenge, the group infiltrated with low viscosity resin presented the lowest means of colour change. 相似文献147.
Mar?o HF Panzarini SR Aranega AM Sonoda CK Poi WR Esteves JC Silva PI 《Dental traumatology》2012,28(4):306-313
Clinical experience has shown that most avulsed teeth are replanted after a long extra-alveolar time and dry or inadequate wet storage, causing necrosis of periodontal ligament cells. This condition invariably leads to development of external root resorption, leaving the filling material in contact with the periapical connective tissues. In this study, the periapical tissue reactions to calcium hydroxide (CH) and mineral trioxide aggregate (MTA) were evaluated after occurrence of external root resorption as an expected sequela of delayed tooth replantation. Twenty male Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. Then, the dental papilla, enamel organ, pulp tissue, and periodontal ligament were removed, and the teeth were immersed in a 2% acidulated phosphate sodium fluoride solution, pH 5.5, for 10 min. The teeth were randomly assigned into two groups (n = 10), in which the canals were filled with either a CH and saline paste (CH group) or MTA (MTA group). The sockets were irrigated with saline, and the teeth were replanted. After 80 days, it was possible to observe large areas of replacement root resorption and some areas of inflammatory root resorption in both groups. More severe inflammatory tissue reaction was observed in contact with calcium hydroxide compared with the mineral trioxide aggregate. New bone formation was more intense at the bottom of the socket in the MTA group. In conclusion, as far as periapical tissue compatibility is concerned, intracanal MTA can be considered as a viable option for root canal filling in delayed tooth replantation, in which external root resorption is an expected sequela. 相似文献
148.
Inflammasomes are large multiprotein platforms that mediate the processing of caspase‐1, which in turn promotes the maturation and release of IL‐1β and IL‐18 in response to microbial and danger signals. While the canonical pathway of inflammasome activation has been known for some time, a novel mechanism of noncanonical inflammasome activation mediated by caspase‐11 was more recently identified. This pathway engages caspase‐11 to trigger both caspase‐1‐dependent and ‐independent production of the inflammatory cytokines IL‐1β, IL‐18, and IL‐1α, as well as to promote pyroptosis, a form of genetically programmed cell death that is associated with the release of such cytokines. In this review, we gather together studies on both the mechanisms and implications of caspase‐11‐mediated noncanonical inflammasome activation, and discuss the emerging importance of this pathway in regulating host defense against intracellular bacterial pathogens. 相似文献
149.
150.
Alessandra Pierangeli Carolina Scagnolari Simona Trombetti Rosanna Grossi Massimo Battaglia Corrado Moretti Fabio Midulla Guido Antonelli 《Influenza and other respiratory viruses》2008,2(5):175-179
Background Human bocavirus (HBoV) was first discovered in Sweden in 2005 and has now been found worldwide; however its role in clinically relevant diseases has not yet been clearly defined. Objectives To gain new insight into HBoV infection among children hospitalized with acute respiratory infections in Rome. Methods Between November 2004 and May 2007, 415 nasal washings were tested for the presence of an extensive range of respiratory viruses using molecular methods. Results Viral pathogens were detected in 214 children (51·6%), 28·9% being respiratory syncytial virus (RSV) and 9·6% being rhinovirus positive. Of the 34 children (8·2%) who tested positive for HBoV, 21 (61·8%) were co‐infected with another respiratory virus, mainly RSV. Human bocavirus was the only pathogen identified in four pneumonia and six bronchiolitis cases in March 2005 and January 2007, respectively. Human bocavirus was also detected in one child hospitalized with gastroenteritis and in another with erythema. Conclusions In the examined population, HBoV was the third most common virus detected but with a high rate of co‐infection with other respiratory viruses. Human bocavirus appeared to be the etiological agent in some pneumonia and bronchiolitis cases in which tests for all likely respiratory pathogens were negative. 相似文献