全文获取类型
收费全文 | 1306篇 |
免费 | 94篇 |
国内免费 | 7篇 |
学科分类
医药卫生 | 1407篇 |
出版年
2023年 | 12篇 |
2022年 | 16篇 |
2021年 | 32篇 |
2020年 | 19篇 |
2019年 | 29篇 |
2018年 | 38篇 |
2017年 | 23篇 |
2016年 | 41篇 |
2015年 | 36篇 |
2014年 | 66篇 |
2013年 | 68篇 |
2012年 | 89篇 |
2011年 | 119篇 |
2010年 | 51篇 |
2009年 | 56篇 |
2008年 | 105篇 |
2007年 | 109篇 |
2006年 | 80篇 |
2005年 | 76篇 |
2004年 | 92篇 |
2003年 | 73篇 |
2002年 | 71篇 |
2001年 | 12篇 |
2000年 | 9篇 |
1999年 | 13篇 |
1998年 | 8篇 |
1997年 | 11篇 |
1996年 | 9篇 |
1995年 | 8篇 |
1994年 | 7篇 |
1993年 | 4篇 |
1992年 | 6篇 |
1991年 | 3篇 |
1990年 | 3篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 2篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1983年 | 3篇 |
1981年 | 2篇 |
1979年 | 1篇 |
排序方式: 共有1407条查询结果,搜索用时 227 毫秒
1.
Ziv Dadon Eli Ben-Chetrit Ofer Benjaminov Louay Taha Yonit Wiener-Well Daniel Belman Phillip D. Levin 《Clinical microbiology and infection》2021,27(4):635.e1-635.e4
ObjectiveTo assess the role of the computerized tomography (CT) scanner in cross-transmission of carbapenem-resistant Acinetobacter baumannii between hospitalized patients undergoing CT scan.MethodsA single-centre retrospective observational analysis of inpatients undergoing CT scans. Patient-unique CT scans were defined as ‘index cases’ (patients undergoing CT scan with carbapenem-resistant Acinetobacter baumannii (CRAB) colonization documented during the previous 60 days), ‘incident cases’ (patients found colonized with CRAB within 14 days following CT scan), and ‘negative cases’ (negative for CRAB before and after CT scan). CRAB acquisition was analysed by time interval between CT scan and CT scan of the prior index-case patient.ResultsAmongst 73 047 CT scans performed over 5 years, 4834 scans were performed within 12 hours of an index case. CRAB acquisition was detected in 20 patients (incident cases), including 16/2725 (5.8/1000 scans) who underwent CT scan within 6 hours of an index-case CT scan and 4/2109 (1.9/1000 scans) who had their CT scan 7–12 hours after the CT scan of an index-case patient (p 0.033, risk ratio 3.1, 95%CI 1.03–9.25). Patient characteristics for the two time periods were similar. While not the only significant predictor of CRAB acquisition (others included age and length of hospital stay prior to the CT scan), the time elapsed from an index case remained a significant predictor for CRAB acquisition on multivariate analysis (OR 0.84, 95%CI 0.74–0.95, p 0.007).ConclusionsPerforming a CT scan within 6 hours of a CT scan performed in a CRAB-positive patient was an independent predictor of CRAB acquisition, approximately tripling the risk. This probably reflects poor infection control practice in the CT suite. 相似文献
2.
OBJECTIVES: To determine the influence of two enamel conditioning techniques on buccal and lingual tooth surfaces at two different times on debonding strength and tooth damage. METHODS: The study included 50 premolars. Buccal and lingual surfaces of 10 teeth were scanned using SEM before (N=4) and after enamel conditioning by either acid etching or sandblasting prior to acid etching (N=6) for their morphology. The remaining 40 teeth were divided into 2 equal groups, differing in enamel conditioning prior to metallic bracket bonding on the buccal and lingual surfaces. Each group was equally subdivided into short-term (48h) or long-term (12m) water storage. Debonding strength was measured followed by SEM and EDAX for adhesive remnant index (ARI) and calcium remnant index (CRI) left on bracket bases. ANOVA with repeated measures was applied to the results. RESULTS: The buccal enamel was rougher than the lingual one. The surface morphology after the two types of conditioning showed a different pattern. A significantly higher debonding strength was needed to debond the buccal brackets compared to the lingual ones (p<0.05). A significantly higher ARI (p<0.002) and higher CRI (p<0.005) were found in the lingual surface compared with the buccal. No differences were found in debonding strength ARI or CRI regarding the different conditioning or storage duration. CONCLUSIONS: Lingual bonding leads to higher ARI and CRI than buccal bonding. Sandblasting prior to etching does not improve bonding strength for lingual or buccal bonding. 相似文献
3.
Karl Schoknecht Ofer Prager Udi Vazana Lyn Kamintsky Denise Harhausen Marietta Zille Lena Figge Yoash Chassidim Eyk Schellenberger Richard Kovács Uwe Heinemann Alon Friedman 《Journal of cerebral blood flow and metabolism》2014,34(11):1791-1801
Focal cerebral ischemia is among the main causes of death and disability worldwide. The ischemic core often progresses, invading the peri-ischemic brain; however, assessing the propensity of the peri-ischemic brain to undergo secondary damage, understanding the underlying mechanisms, and adjusting treatment accordingly remain clinically unmet challenges. A significant hallmark of the peri-ischemic brain is dysfunction of the blood–brain barrier (BBB), yet the role of disturbed vascular permeability in stroke progression is unclear. Here we describe a longitudinal in vivo fluorescence imaging approach for the evaluation of cortical perfusion, BBB dysfunction, free radical formation and cellular injury using the photothrombosis vascular occlusion model in male Sprague Dawley rats. Blood–brain barrier dysfunction propagated within the peri-ischemic brain in the first hours after photothrombosis and was associated with free radical formation and cellular injury. Inhibiting free radical signaling significantly reduced progressive cellular damage after photothrombosis, with no significant effect on blood flow and BBB permeability. Our approach allows a dynamic follow-up of cellular events and their response to therapeutics in the acutely injured cerebral cortex. 相似文献
4.
5.
Konigstein Maayan Biner Simon Topilsky Yan Abramowitz Yigal Havakuk Ofer Ben-Assa Eyal Leshem-Rubinow Eran Arbel Yaron Keren Gad Banai Shmuel Finkelstein Ariel 《Journal of Echocardiography》2014,12(1):17-23
Background
Aortic stenosis is associated with concentric left ventricle (LV) hypertrophy or remodeling resulting in impaired diastolic function and elevated left-sided filling pressure. We investigated the changes in LV geometry and LV filling hemodynamics, giving emphasis to parameters associated with changes in diastolic function after transcatheter aortic valve implantation (TAVI).Methods
Comprehensive diastolic assessment was performed before and six months after TAVI in 70 patients with severe aortic stenosis. Patients with any degree of mitral stenosis or >mild left-sided valvular regurgitation were excluded.Results
In the entire cohort six months after TAVI, LV end-diastolic diameter increased (44.1 ± 6 versus 45 ± 6 mm, P = 0.02), whereas LV mass and relative wall thickness (RWT) decreased (270.1 ± 76 versus 245.1 ± 75 g and 0.53 ± 0.15 versus 0.46 ± 0.1, respectively; P < 0.0001 for both). Lateral e′ increased (5.8 ± 2 versus 6.6 ± 3 cm/s, P = 0.03) and left atrium (LA) volume, E/e′ ratio, and systolic pulmonary pressure decreased (88.1 ± 30 versus 80 ± 28 cc, 18 ± 7.8 versus 16.3 ± 5.5, and 42.7 ± 14.9 versus 38.7 ± 12 mmHg, respectively; P < 0.05 for all), suggesting reduction in LA pressure. The improvement in LA volume and E/e′ was almost exclusively seen in patients with LV hypertrophy before TAVI (P < 0.05 both), as opposed to patients with concentric remodeling.Conclusions
In our preliminary study, TAVI resulted in LV and LA reverse remodeling, and improved LV relaxation and LA filling pressure in patients with severe aortic stenosis and concentric hypertrophy. Patients with concentric remodeling at baseline seem to have limited improvement in LV diastolic function and filling pressure following TAVI, but larger clinical trials would be required to conclude if they have no improvement at all. 相似文献6.
7.
Tilman J. Alpermann Jörg Plieske Ahmad O. Mal Ofer Gon Michael L. Berumen 《Conservation Genetics Resources》2014,6(4):1031-1034
The cardinalfish Siphamia tubifer has been selected as a model for the study of genetic connectivity in reef-associated fishes among marine-protected-areas in Socotra Island in the northwestern Indian Ocean (part of the Socotra Archipelago, a UNESCO World Heritage Site since 2008). Twenty-six novel microsatellite markers are described for S. tubifer and are now available for studies on its genetic population structure. In a population sample from Socotra Island, the newly developed markers possessed between three and 20 alleles. Expected and observed heterozygosity ranged from 0.56–0.96 to 0.55–0.95, respectively. The markers did not show deviations from Hardy–Weinberg equilibrium and were not in linkage disequilibrium. 相似文献
8.
Ahmad Assalia Anat Ilivitzki Amos Ofer Alain Suissa Elias Manassa Iyad Khamaysi Ahmad Mahajna 《Surgery for obesity and related diseases》2018,14(8):1093-1098
Background
Laparoscopic sleeve gastrectomy (LSG) is considered as a first line treatment for morbid obesity around the globe. Leakage and subsequent gastric fistula is the most dreadful complication, which may lead to serious morbidity and even mortality.Objectives
To assess the safety and efficacy of fibrin glue application in the setting of gastric fistula after LSG.Setting
University hospital, Israel.Methods
Twenty-four morbidly obese patients (mean age?=?42.2 yr, mean body mass index?=?42 kg/m2) developed gastric fistula after LSG. The fistula was acute in 10 patients, subacute in 9, and chronic in 5. Sixteen patients (67%) have had previous failed endoscopic interventions. Fibrin glue was applied percutaneously with fluoroscopic guidance, under endoscopic visualization. A pigtail drain was left in the distal tract to monitor and manage possible continuous leakage.Results
There were no complications except abdominal pain in 2 patients associated with fever in 1. Both resolved within 1 to 2 days. Fistula closure was achieved in all patients but 1 (95.8%). Closure was accomplished after a single application in 9 patients (39%), 2 applications in 8, 3 applications in 3, 5 applications in 2, and 6 applications in 1. All patients were followed with a mean time of 42.3 months (range, 20–46).Conclusions
Although in most patients there was a need for multiple applications, our experience indicates that percutaneous fluoroscopic application of Fibrin glue under endoscopic visualization proved to be a simple, tolerable, and highly effective method for the treatment of selected patients with gastric fistula after LSG. 相似文献9.
The development of the reprogramming technology led to generation of induced Pluripotent Stem Cells (iPSC) from a variety of somatic cells. Ever since, fast growing knowledge of different efficient protocols enabled the differentiation of these iPSCs into different cells types utilized for disease modeling. Indeed, iPSC-derived cells have been increasingly used for investigating molecular and cellular pathophysiological mechanisms underlying inherited diseases. However, a major barrier in the field of iPSC-based disease modeling relies on discriminating between the effects of the causative mutation and the genetic background of these cells. In the past decade, researchers have made great improvement in genome editing techniques, with one of the latest being CRISPR/Cas9. Using a single non-sequence specific protein combined with a small guiding RNA molecule, this state-of-the-art approach enables modifications of genes with high efficiency and accuracy. By so doing, this technique enables the generation of isogenic controls or isogenic mutated cell lines in order to focus on the pathologies caused by a specific mutation. In this article, we review the latest studies combining iPSC and CRISPR/Cas9 technologies for the investigation of the molecular and cellular mechanisms underlying inherited diseases including immunological, metabolic, hematological, neurodegenerative and cardiac diseases. 相似文献
10.