全文获取类型
收费全文 | 3684篇 |
免费 | 284篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 24篇 |
儿科学 | 129篇 |
妇产科学 | 82篇 |
基础医学 | 570篇 |
口腔科学 | 116篇 |
临床医学 | 395篇 |
内科学 | 781篇 |
皮肤病学 | 38篇 |
神经病学 | 293篇 |
特种医学 | 274篇 |
外科学 | 275篇 |
综合类 | 31篇 |
一般理论 | 1篇 |
预防医学 | 348篇 |
眼科学 | 92篇 |
药学 | 272篇 |
中国医学 | 4篇 |
肿瘤学 | 258篇 |
出版年
2023年 | 34篇 |
2022年 | 82篇 |
2021年 | 137篇 |
2020年 | 69篇 |
2019年 | 101篇 |
2018年 | 112篇 |
2017年 | 83篇 |
2016年 | 85篇 |
2015年 | 96篇 |
2014年 | 120篇 |
2013年 | 162篇 |
2012年 | 222篇 |
2011年 | 216篇 |
2010年 | 136篇 |
2009年 | 113篇 |
2008年 | 164篇 |
2007年 | 197篇 |
2006年 | 165篇 |
2005年 | 161篇 |
2004年 | 143篇 |
2003年 | 122篇 |
2002年 | 129篇 |
2001年 | 52篇 |
2000年 | 26篇 |
1999年 | 48篇 |
1998年 | 72篇 |
1997年 | 84篇 |
1996年 | 71篇 |
1995年 | 66篇 |
1994年 | 66篇 |
1993年 | 44篇 |
1992年 | 33篇 |
1991年 | 30篇 |
1990年 | 29篇 |
1989年 | 39篇 |
1988年 | 50篇 |
1987年 | 30篇 |
1986年 | 50篇 |
1985年 | 40篇 |
1984年 | 22篇 |
1983年 | 27篇 |
1982年 | 40篇 |
1981年 | 16篇 |
1980年 | 18篇 |
1979年 | 20篇 |
1978年 | 14篇 |
1977年 | 16篇 |
1976年 | 26篇 |
1975年 | 14篇 |
1972年 | 14篇 |
排序方式: 共有3983条查询结果,搜索用时 15 毫秒
91.
Borrelli Enrico Grosso Domenico Vella Giovanna Sacconi Riccardo Querques Lea Zucchiatti Ilaria Prascina Francesco Bandello Francesco Querques Giuseppe 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(12):2655-2660
Graefe's Archive for Clinical and Experimental Ophthalmology - To quantify the shrinking in outpatient and intravitreal injections’ volumes in a tertiary referral retina unit secondary to... 相似文献
92.
Ay C Jungbauer LV Sailer T Tengler T Koder S Kaider A Panzer S Quehenberger P Pabinger I Mannhalter C 《Clinical chemistry》2007,53(7):1235-1243
BACKGROUND: The cell adhesion molecule P-selectin has an important role in the pathophysiology of thrombosis. The effect on venous thromboembolism (VTE) of increased circulating concentrations of soluble P-selectin (sP-selectin) and their association with the P-selectin variant Thr715Pro is still uncertain. METHODS: This study was a case-control study of 116 patients with confirmed recurrent VTE and at least 1 event of unprovoked deep venous thrombosis or pulmonary embolism, and 129 age- and sex-matched healthy individuals. We measured sP-selectin by ELISA and P-selectin gene (SELP) variation by genotyping and sampled blood after a mean interval of 2.55 years after the most recent VTE event. RESULTS: The mean (SD) sP-selectin concentration was higher in patients than in controls: 47.3 (15.0) microg/L vs 36.8 (11.0) microg/L, P <0.001. The unadjusted odds ratio (OR) for sP-selectin >55.1 microg/L, representing the 95th percentile for controls, was 8.5 (95% CI, 3.7-23.3; P <0.001) and increased after adjustment for factor V Leiden, the prothrombin G20210A variant, increased factor VIII, and hyperhomocysteinemia (OR, 10.6; 95% CI, 4.1-31.2; P <0.001). Pro715 carriers were more prevalent among controls than patients (21.7% vs 14.7%). sP-selectin concentrations were lower in this subgroup than in noncarriers: 31.3 (7.9) microg/L vs 44.1 (14.1) microg/L; P <0.001). CONCLUSIONS: Increased sP-selectin concentrations are associated with VTE and genotype status. sP-selectin concentrations are lower in individuals carrying the P-selectin Pro715 variant than in those without this variant. 相似文献
93.
94.
95.
Matthias Vonmoos Lea M Hulka Katrin H Preller Franziska Minder Markus R Baumgartner Boris B Quednow 《Neuropsychopharmacology》2014,39(9):2200-2210
Cocaine users consistently display cognitive impairments. However, it is still unknown whether these impairments are cocaine-induced and if they are reversible. Therefore, we examined the relation between changing intensity of cocaine use and the development of cognitive functioning within 1 year. The present data were collected as part of the longitudinal Zurich Cocaine Cognition Study (ZuCo2St). Forty-eight psychostimulant-naive controls and 57 cocaine users (19 with increased, 19 with decreased, and 19 with unchanged cocaine use) were eligible for analysis. At baseline and after a 1-year follow-up, cognitive performance was measured by a global cognitive index and four neuropsychological domains (attention, working memory, declarative memory, and executive functions), calculated from 13 parameters of a broad neuropsychological test battery. Intensity of cocaine use was objectively determined by quantitative 6-month hair toxicology at both test sessions. Substantially increased cocaine use within 1 year (mean +297%) was associated with reduced cognitive performance primarily in working memory. By contrast, decreased cocaine use (−72%) was linked to small cognitive improvements in all four domains. Importantly, users who ceased taking cocaine seemed to recover completely, attaining a cognitive performance level similar to that of the control group. However, recovery of working memory was correlated with age of onset of cocaine use—early-onset users showed hampered recovery. These longitudinal data suggest that cognitive impairment might be partially cocaine-induced but also reversible within 1 year, at least after moderate exposure. The reversibility indicates that neuroplastic adaptations underlie cognitive changes in cocaine users, which are potentially modifiable in psychotherapeutical or pharmacological interventions. 相似文献
96.
Lucijan Skubic Lea Honjak Jeannette P. Staheli Michael R. Dyen Rebecca M. Ducore Lois M. A. Colgin Anne D. Lewis Mario Poljak 《Viruses》2021,13(4)
Papillomaviruses (PVs) are a diverse group of host species-specific DNA viruses, etiologically linked with various benign and malignant neoplasms of cutaneous and mucosal epithelia. Here, we describe the detection and characterization of the first two PVs naturally infecting Japanese macaques (Macaca fuscata), including the determination of their etiological association(s) with the development of original neoplasms. The molecular and phylogenetic analyses were performed on complete genome sequences of Macaca fuscata PV types 1 (MfuPV1) and 2 (MfuPV2), which were completely sequenced in samples of a malignant oral tumor and benign anogenital neoplasm of Japanese macaques, respectively. Subsequently, two type-specific quantitative real-time PCRs were developed to estimate viral loads of MfuPV1 and MfuPV2 and to evaluate their etiological roles. The in silico molecular analyses revealed that both viral genomes encode characteristic PV proteins with conserved functional domains and have a non-coding genomic region with regulatory sequences to regulate and complete the viral life cycle. However, additional experimental evidence is needed to finally confirm the presence and biological functionality of the molecular features of both novel PVs. While MfuPV1, together with PVs identified in other macaques, is classified into the Alphapapillomavirus (Alpha-PV) species 12, MfuPV2 is most likely a representative of the novel viral species within the Alpha-PV genus. Their relatively high viral loads suggest that both PVs are etiologically linked with the development of the original neoplasms. 相似文献
97.
98.
99.
100.
Mariarosa Pascale Simona Laurino Heiko Vogel Annalisa Grimaldi Magnus Monné Lea Riviello Gianluca Tettamanti Patrizia Falabella 《Developmental and comparative immunology》2014
Hemocytes of Heliothis virescens (F.) (Lepidoptera, Noctuidae) larvae produce a protein, P102, with a putative endoribonuclease-U domain. In previous works we have shown that P102 is involved in Lepidopteran immune response by forming amyloid fibrils, which catalyze and localize melanin deposition around non-self intruders during encapsulation, preventing harmful systemic spreading. Here we demonstrate that P102 belongs to a new class of proteins that, at least in Lepidoptera, has a diminished endoribonuclease-U activity probably due to the lack of two out of five catalytically essential residues. We show that the P102 homolog from Trichoplusia ni (Lepidoptera, Noctuidae) displays catalytic site residues identical to P102, a residual endoribonuclease-U activity and the ability to form functional amyloids. On the basis of these results as well as sequence and structural analyses, we hypothesize that all the Lepidoptera endoribonuclease-U orthologs with catalytic site residues identical to P102 form a subfamily with similar function. 相似文献