全文获取类型
收费全文 | 16062篇 |
免费 | 1108篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 205篇 |
儿科学 | 561篇 |
妇产科学 | 506篇 |
基础医学 | 2306篇 |
口腔科学 | 487篇 |
临床医学 | 1363篇 |
内科学 | 3719篇 |
皮肤病学 | 351篇 |
神经病学 | 1411篇 |
特种医学 | 326篇 |
外科学 | 1786篇 |
综合类 | 106篇 |
一般理论 | 8篇 |
预防医学 | 1718篇 |
眼科学 | 357篇 |
药学 | 1054篇 |
中国医学 | 81篇 |
肿瘤学 | 883篇 |
出版年
2023年 | 111篇 |
2022年 | 235篇 |
2021年 | 580篇 |
2020年 | 321篇 |
2019年 | 486篇 |
2018年 | 567篇 |
2017年 | 402篇 |
2016年 | 404篇 |
2015年 | 494篇 |
2014年 | 657篇 |
2013年 | 806篇 |
2012年 | 1218篇 |
2011年 | 1308篇 |
2010年 | 780篇 |
2009年 | 628篇 |
2008年 | 1055篇 |
2007年 | 1046篇 |
2006年 | 951篇 |
2005年 | 907篇 |
2004年 | 780篇 |
2003年 | 698篇 |
2002年 | 659篇 |
2001年 | 229篇 |
2000年 | 242篇 |
1999年 | 223篇 |
1998年 | 119篇 |
1997年 | 75篇 |
1996年 | 60篇 |
1995年 | 72篇 |
1994年 | 59篇 |
1993年 | 62篇 |
1992年 | 103篇 |
1991年 | 74篇 |
1990年 | 80篇 |
1989年 | 81篇 |
1988年 | 62篇 |
1987年 | 66篇 |
1986年 | 49篇 |
1985年 | 46篇 |
1984年 | 39篇 |
1983年 | 31篇 |
1982年 | 20篇 |
1979年 | 24篇 |
1978年 | 22篇 |
1976年 | 24篇 |
1975年 | 22篇 |
1974年 | 24篇 |
1973年 | 27篇 |
1971年 | 24篇 |
1970年 | 22篇 |
排序方式: 共有10000条查询结果,搜索用时 93 毫秒
1.
Primary cutaneous anaplastic large cell lymphomas with 6p25.3 rearrangement exhibit particular histological features 下载免费PDF全文
2.
N. S. Hari Narayana Moorthy Sergio F. Sousa Maria J. Ramos Pedro A. Fernandes 《Medicinal chemistry research》2016,25(7):1340-1357
Farnesyltransferase (FTase) is one of the prenyltransferase family enzymes that catalyse the transfer of 15-membered isoprenoid (farnesyl) moiety to the cysteine of CAAX motif-containing proteins including Rho and Ras family of G proteins. Inhibitors of FTase act as drugs for cancer, malaria, progeria and other diseases. In the present investigation, we have developed two structure-based pharmacophore models from protein–ligand complex (3E33 and 3E37) obtained from the protein data bank. Molecular dynamics (MD) simulations were performed on the complexes, and different conformers of the same complex were generated. These conformers were undergone protein–ligand interaction fingerprint (PLIF) analysis, and the fingerprint bits have been used for structure-based pharmacophore model development. The PLIF results showed that Lys164, Tyr166, TrpB106 and TyrB361 are the major interacting residues in both the complexes. The RMSD and RMSF analyses on the MD-simulated systems showed that the absence of FPP in the complex 3E37 has significant effect in the conformational changes of the ligands. During this conformational change, some interactions between the protein and the ligands are lost, but regained after some simulations (after 2 ns). The structure-based pharmacophore models showed that the hydrophobic and acceptor contours are predominantly present in the models. The pharmacophore models were validated using reference compounds, which significantly identified as HITs with smaller RMSD values. The developed structure-based pharmacophore models are significant, and the methodology used in this study is novel from the existing methods (the original X-ray crystallographic coordination of the ligands is used for the model building). In our study, along with the original coordination of the ligand, different conformers of the same complex (protein–ligand) are used. It concluded that the developed methodology is significant for the virtual screening of novel molecules on different targets. 相似文献
3.
Enrique Luengo Izaskun Buendia Cristina Fernndez‐Mendívil Paula Trigo‐Alonso Pilar Negredo Patrycja Michalska Borja Hernndez‐García Cristina Snchez‐Ramos Juan A. Bernal Tsuneya Ikezu Rafael Len Manuela G. Lpez 《Journal of pineal research》2019,67(1)
Alterations in autophagy are increasingly being recognized in the pathogenesis of proteinopathies like Alzheimer's disease (AD). This study was conducted to evaluate whether melatonin treatment could provide beneficial effects in an Alzheimer model related to tauopathy by improving the autophagic flux and, thereby, prevent cognitive decline. The injection of AAV‐hTauP301L viral vectors and treatment/injection with okadaic acid were used to achieve mouse and human ex vivo, and in vivo tau‐related models. Melatonin (10 μmol/L) impeded oxidative stress, tau hyperphosphorylation, and cell death by restoring autophagy flux in the ex vivo models. In the in vivo studies, intracerebroventricular injection of AAV‐hTauP301L increased oxidative stress, neuroinflammation, and tau hyperphosphorylation in the hippocampus 7 days after the injection, without inducing cognitive impairment; however, when animals were maintained for 28 days, cognitive decline was apparent. Interestingly, late melatonin treatment (10 mg/kg), starting once the alterations mentioned above were established (from day 7 to day 28), reduced oxidative stress, neuroinflammation, tau hyperphosphorylation, and caspase‐3 activation; these observations correlated with restoration of the autophagy flux and memory improvement. This study highlights the importance of autophagic dysregulation in tauopathy and how administration of pharmacological doses of melatonin, once tauopathy is initiated, can restore the autophagy flux, reduce proteinopathy, and prevent cognitive decline. We therefore propose exogenous melatonin supplementation or the development of melatonin derivatives to improve autophagy flux for the treatment of proteinopathies like AD. 相似文献
4.
5.
6.
7.
8.
Águeda Prior-Español Yaiza García-Mira Sonia Mínguez Melania Martínez-Morillo Laia Gifre Lourdes Mateo 《Reumatología clinica》2019,15(6):e81-e85
ObjectiveSeptic arthritis is a medical emergency and crystal-induced arthritis is a risk factor for its development. If both occur simultaneously, crystal-induced arthritis may mask the diagnosis of infection and delay antibiotic therapy.MethodRetrospective analysis of patients with coexistence of septic and crystal-induced arthritis. We included only patients with isolation of crystals in synovial fluid analysis and positive culture of synovial fluid and/or blood culture.ResultsA total of 25 patients (17 men and 8 women) with a mean age of 67 years. The most commonly affected joint was the knee. In synovial fluid cytological studies, the most frequently identified crystals were monosodium urate. Risk factors included diabetes and chronic renal failure. The most frequently isolated germs were methicillin-sensitive S. aureus (48%), methicillin-resistant S. aureus (12%) and Mycobacterium tuberculosis (12%). In all, 36% of subjects required surgical drainage (excluding those caused by M. tuberculosis). Clinical outcome was favorable in 56%, although intercurrent complications were usual (40%). Mortality was 8%.ConclusionsCoexistence of septic and crystal-induced arthritis represents a diagnostic challenge and requires a high index of suspicion. Gout was the most prevalent crystal-induced arthritis. S. aureus was the most commonly causative pathogen, with a high rate of methicillin-resistant S. aureus infection. If treated early, the outcome is usually favorable, making synovial fluid microbiological study imperative. 相似文献
9.
Kristina W. Whitworth Brenda Berumen-Flucker George L. Delclos Sonia Fragoso Claudia Mata David Gimeno Ruiz de Porras 《Archives of environmental & occupational health》2020,75(2):70-74
AbstractThe occupational hazards and respiratory symptoms of domestic cleaners in USA are largely unknown. We conducted a cross-sectional study among 56 Hispanic female domestic cleaner on their health status and frequency of cleaning products used and tasks performed. While women used multi-use products (60.0%) and toilet bowl cleaners (51.8%) most days of the week, many (39.3%) reported not using personal protective equipment while cleaning. Itchy/watery eyes (61.8%) and itchy nose (56.4%) were the most frequently reported symptoms. A history of physician-diagnosed asthma was reported by 14.3% while 33.9% had symptoms of bronchial hyperresponsiveness (BHR). In conclusion, this vulnerable population has high prevalence of physician-diagnosis asthma and BHR symptoms and is potentially exposed to myriad occupational hazards. Further research exploring associations between products use, cleaning tasks and respiratory symptoms is warranted. 相似文献
10.
Regina Gershkovich David Sacks Abraham Chlibovsky Sonia Yudaev Asher Korzets 《Nephrology, dialysis, transplantation》2006,21(2):539-540
Case report A 28-year-old female patient was admitted because of painlessmacroscopic haematuria. Past history included severe mentalretardation and nystagmus. At age 17, a computed tomography(CT) scan of the brain showed an absent cerebellar vermis andcerebellar hypoplasia. There was no 相似文献