全文获取类型
收费全文 | 1460篇 |
免费 | 28篇 |
国内免费 | 8篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 25篇 |
妇产科学 | 35篇 |
基础医学 | 93篇 |
口腔科学 | 13篇 |
临床医学 | 141篇 |
内科学 | 442篇 |
皮肤病学 | 3篇 |
神经病学 | 106篇 |
特种医学 | 38篇 |
外科学 | 372篇 |
综合类 | 8篇 |
预防医学 | 35篇 |
眼科学 | 7篇 |
药学 | 61篇 |
肿瘤学 | 116篇 |
出版年
2023年 | 8篇 |
2022年 | 6篇 |
2021年 | 22篇 |
2020年 | 14篇 |
2019年 | 11篇 |
2018年 | 15篇 |
2017年 | 10篇 |
2016年 | 15篇 |
2015年 | 17篇 |
2014年 | 29篇 |
2013年 | 42篇 |
2012年 | 57篇 |
2011年 | 77篇 |
2010年 | 52篇 |
2009年 | 80篇 |
2008年 | 88篇 |
2007年 | 112篇 |
2006年 | 130篇 |
2005年 | 134篇 |
2004年 | 87篇 |
2003年 | 95篇 |
2002年 | 95篇 |
2001年 | 37篇 |
2000年 | 28篇 |
1999年 | 39篇 |
1998年 | 19篇 |
1997年 | 20篇 |
1996年 | 10篇 |
1995年 | 19篇 |
1994年 | 10篇 |
1993年 | 7篇 |
1992年 | 10篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 3篇 |
1988年 | 5篇 |
1987年 | 12篇 |
1986年 | 4篇 |
1985年 | 8篇 |
1984年 | 5篇 |
1983年 | 4篇 |
1982年 | 3篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1979年 | 4篇 |
1978年 | 2篇 |
1977年 | 5篇 |
1967年 | 2篇 |
1966年 | 2篇 |
1925年 | 2篇 |
排序方式: 共有1496条查询结果,搜索用时 757 毫秒
21.
Sebastian Roka Michael Fiegl Niklas Zojer Martin Filipits Rudolf Schuster Birgit Steiner Raimund Jakesz Heinz Huber Johannes Drach 《Breast cancer research and treatment》1998,48(2):125-133
Previous work from our laboratory demonstrated aneuploidy for several chromosomes by interphase fluorescence in situ hybridization (FISH) in a high proportion of breast cancer specimens. In the literature, only limited data are available concerning chromosome 8 anomalies in breast cancer. To determine chromosome 8 ploidy status in primary and metastatic specimens from 81 breast cancer patients, FISH analysis with a DNA probe recognizing chromosome 8 centromeres was performed. In all primary tumor specimens (n=30), significant proportions of cells were aneuploid exhibiting gain of chromosome 8 copy numbers; in 75% of effusion specimens previously classified as malignant by cytology and/or FISH for various chromosomes (n=40), cell populations aneuploid for chromosome 8 were detected; effusions previously classified non-malignant (n=11) were diploid in 10 cases, whereas one specimen contained rare hyperdiploid cells. Among these cells complex chromosomal aneuploidy could be demonstrated by two-color FISH, suggesting malignancy. Trisomic and tetrasomic clones were predominant in the majority of samples, but a marked intratumor cytogenetic heterogeneity was observed in most cases. Primary tumors and corresponding positive axillary lymph nodes revealed similar distributions of chromosome 8 copy numbers, analogous to previous findings with other chromosomes. This implies that, by using suitable FISH probes after examination of the respective primary tumor, an efficient search for (micro)metastasis might be feasible. 相似文献
22.
23.
Anne Krogh Nhr Morten Lindow Annika Forsingdal Samuel Demharter Troels Nielsen Raimund Buller Ida Moltke Morana Vitezic Anders Albrechtsen 《Neuropsychopharmacology》2021,46(7):1324
A better understanding of the biological factors underlying antidepressant treatment in patients with major depressive disorder (MDD) is needed. We perform gene expression analyses and explore sources of variability in peripheral blood related to antidepressant treatment and treatment response in patients suffering from recurrent MDD at baseline and after 8 weeks of treatment. The study includes 281 patients, which were randomized to 8 weeks of treatment with vortioxetine (N = 184) or placebo (N = 97). To our knowledge, this is the largest dataset including both gene expression in blood and placebo-controlled treatment response measured by a clinical scale in a randomized clinical trial. We identified three novel genes whose RNA expression levels at baseline and week 8 are significantly (FDR < 0.05) associated with treatment response after 8 weeks of treatment. Among these genes were SOCS3 (FDR = 0.0039) and PROK2 (FDR = 0.0028), which have previously both been linked to depression. Downregulation of these genes was associated with poorer treatment response. We did not identify any genes that were differentially expressed between placebo and vortioxetine groups at week 8 or between baseline and week 8 of treatment. Nor did we replicate any genes identified in previous peripheral blood gene expression studies examining treatment response. Analysis of genome-wide expression variability showed that type of treatment and treatment response explains very little of the variance, a median of <0.0001% and 0.05% in gene expression across all genes, respectively. Given the relatively large size of the study, the limited findings suggest that peripheral blood gene expression might not be the best approach to explore the biological factors underlying antidepressant treatment.Subject terms: Predictive markers, Depression 相似文献
24.
Alberto Addis Maxime Gaasch Alois J Schiefecker Mario Kofler Bogdan Ianosi Verena Rass Anna Lindner Gregor Broessner Ronny Beer Bettina Pfausler Claudius Thom Erich Schmutzhard Raimund Helbok 《Journal of cerebral blood flow and metabolism》2021,41(2):359
Elevated body temperature (Tcore) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (Tbrain) is usually higher than Tcore. However, the implication of this difference (Tdelta) remains unclear. We aimed to study factors associated with higher Tdelta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of Tcore, Tbrain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. Tbrain was tightly correlated with Tcore (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (Tdelta +0.18°C, IQR −0.01 – 0.37°C). A higher Tdelta was associated with better metabolic state, indicated by lower CMD-glutamate (p = 0.003) and CMD-lactate (p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, Tdelta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher Tdelta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that Tbrain is associated with brain metabolic activity and exceeds Tcore when mitochondrial function is preserved. Further studies are needed to understand how Tdelta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH. 相似文献
25.
Dietmann A Helbok R Lackner P Issifou S Lell B Matsiegui PB Reindl M Schmutzhard E Kremsner PG 《The Journal of infectious diseases》2008,197(11):1614-1620
BACKGROUND: Molecular mechanisms involved in the pathogenesis of severe malaria caused by Plasmodium falciparum are not fully understood. Matrix metalloproteinases (MMPs) are enzymes that proteolytically degrade both the extracellular matrix and nonmatrix substances with various functions in the modulation of immune response. The key inhibitors of MMPs are the tissue inhibitors of metalloproteinases (TIMPs). METHODS: We studied levels of MMP-8, MMP-9, TIMP-1, and TIMP-2 on admission and after 24 h, using an enzyme-linked immunosorbent assay, in serum specimens from 50 Gabonese children with severe malaria, 43 children with uncomplicated malaria, and 27 healthy control children. RESULTS: Serum MMP-8 and TIMP-1 levels were significantly higher in the severe malaria and uncomplicated malaria groups, compared with those in the control group (P < .001). TIMP-1 levels were significantly higher in patients with severe malaria, compared with those in patients with uncomplicated malaria (P < .001). High TIMP-1 levels were significantly correlated with malaria severity, as determined by the simplified multiorgan dysfunction score (Spearman rank-correlation coefficient, 0.55; P < .001). CONCLUSIONS: TIMP-1 is associated with signs and symptoms of severe malaria. MMP-8 levels are elevated in patients with severe or uncomplicated P. falciparum malaria. MMPs and TIMPs may be relevant in the pathogenesis of severe malaria, either as proteolytic enzymes that degrade the extracellular matrix or as effectors and regulators of the immune response. 相似文献
26.
Martin Lang Rüdiger Brennecke Michael Haude Ulrich Renneisen Raimund Erbel Jürgen Meyer 《The International Journal of Cardiac Imaging》1995,11(2):105-115
In clinical applications the analysis of X-ray contrast densograms acquired in regions of interest (ROI's) over the myocardium is disturbed by many complex factors. For this reason we acquire redundant densogram information for quality control before extracting densitometric parameters. In our approach, initially some stable measures of quality for densograms are used to lower the influence of poor quality densograms by a quality weighted averaging. For example a shape quality measure, Q1, is calculated using regions of optimal and minimal acceptable quality defined with respect to a prototype densogram. Not a few myocardial ROI's yield densograms that differ from single-source densograms (SSD's) due to e.g. superposition of different perfusion beds or the position of the ROI relative to the coronary sinus or stenoses. This might result in a densogram shape with oscillating or plateau behavior. For densograms of a such general shape many parameters defined in the usual way do not depend smoothly on the densogram values. The conventional definitions of some parameters (appearance time, rise time) are therefore extended for application to multi-maxima densograms as well as to SSD's. These new methods are evaluated using digitized clinical angiocardiograms and are applied to parametric imaging (pixeldensograms) in a slightly modified way. Taking into account the densogram quality, its shape and its origin results in a considerable improvement both for densitometry and parametric imaging of myocardial perfusion.Abbreviations AP
appearance time
- Dmax
maximum density
- LAO 60°
left anterior oblique 60° projection
- LCA
left coronary artery
- MIRT
mean integrated rise time
- MTT
mean transit time
- RAO 30°
right anterior oblique 60° projection
- RCA
right coronary artery
- ROI
region of interest
- RT
rise time
- SSD
single-source densogram
- THM
time of half-maximum, tmax - time of maximum 相似文献
27.
Theodor Baars Ursula Neumann Mona Jinawy Stefanie Hendricks Jan-Peter Sowa Julia K?lsch Mona Riemenschneider Guido Gerken Raimund Erbel Dominik Heider Ali Canbay 《Medicine》2016,95(6)
Detection of high-risk subjects in acute myocardial infarction (AMI) by noninvasive means would reduce the need for intracardiac catheterization and associated complications. Liver enzymes are associated with cardiovascular disease risk. A potential predictive value for liver serum markers for the severity of stenosis in AMI was analyzed.Patients with AMI undergoing percutaneous coronary intervention (PCI; n = 437) were retrospectively evaluated. Minimal lumen diameter (MLD) and percent stenosis diameter (SD) were determined from quantitative coronary angiography. Patients were classified according to the severity of stenosis (SD ≥ 50%, n = 357; SD < 50%, n = 80). Routine heart and liver parameters were associated with SD using random forests (RF). A prediction model (M10) was developed based on parameter importance analysis in RF.Age, alkaline phosphatase (AP), aspartate aminotransferase (AST), and MLD differed significantly between SD ≥ 50 and SD < 50. Age, AST, alanine aminotransferase (ALT), and troponin correlated significantly with SD, whereas MLD correlated inversely with SD. M10 (age, BMI, AP, AST, ALT, gamma-glutamyltransferase, creatinine, troponin) reached an AUC of 69.7% (CI 63.8–75.5%, P < 0.0001).Routine liver parameters are associated with SD in AMI. A small set of noninvasively determined parameters can identify SD in AMI, and might avoid unnecessary coronary angiography in patients with low risk. The model can be accessed via http://stenosis.heiderlab.de. 相似文献
28.
Intracardiac echocardiography: an ideal guiding tool for device closure of interatrial communications. 总被引:4,自引:0,他引:4
Thomas Bartel Thomas Konorza Ulrich Neudorf Tiko Ebralize Holger Eggebrecht Achim Gutersohn Raimund Erbel 《European journal of echocardiography》2005,6(2):92-96
BACKGROUND: This study sought to evaluate safety and radiation exposure when using intracardiac echocardiography (ICE) in comparison to transesophageal echocardiography (TEE) in order to guide transcatheter closure of interatrial communications. METHODS: Eighty patients (44 males, 36 females, mean age 46, SD 13 years) undergoing device closure of atrial septal defect (n=12) or patent foramen ovale (n=68) had the procedure guided by ICE (n=50, group 1) or TEE (n=30, group 2). In group 1, all procedural stages were completely guided by ICE, including imaging of the interatrial communication during balloon sizing, device unfolding and release, and during the final check for adequate positioning. In group 2, exclusive implantation of devices was guided by use of TEE. RESULTS: Especially, the spatial relationship between device and cardiac structures (e.g. the ascending aorta, the interatrial septum and the superior vena cava) was accurately demonstrated in group 1. Image resolution provided by ICE was superior to that of TEE. No severe complications, including any related to ICE, were seen. Fluoroscopy time (FT) and procedure time (PT) were shorter in group 1 than in group 2 (FT: 5.5+/-1.5 min vs. 9.3+/-1.6 min, P<0.0001; PT: 31.9+/-4.6 min vs. 38.8+/-5.8 min, P<0.01). Neither sedation nor anesthesia was required in group 1. CONCLUSIONS: ICE is a safe tool to guide device closure of interatrial communications. For the patient, procedural stress and radiation exposure are negligible. ICE can be considered the guiding tool of choice for device closure, particularly when long or repeated echocardiographic viewing is required. 相似文献
29.
Isolated non-compaction of the ventricular myocardium (INVM), also known as left ventricular hypertrabeculation or spongy myocardium, belongs to the "unclassified" cardiomyopathies according to the World Health Organization. The main characteristic of this entity is a prominent trabeculation of the left ventricle with deep intertrabecular recesses communicating with the ventricular cavity. The pathomechanism of INVM is thought to be an arrest in cardiac myogenesis with persistence of embryonic myocardial morphology. The most frequent clinical manifestations include congestive heart failure, ventricular arrhythmias and systemic thromboembolic events. The therapy of INVM comprises standard medical therapy for heart failure. 相似文献
30.
Nico Dragano Pablo Emilio Verde Susanne Moebus Andreas Stang Axel Schmermund Ulla Roggenbuck Stefan M?hlenkamp Richard Peter Karl-Heinz J?ckel Raimund Erbel Johannes Siegrist 《European journal of cardiovascular prevention and rehabilitation》2007,14(4):568-574
BACKGROUND: Social inequalities of manifest coronary heart diseases are well documented in modern societies. Less evidence is available on subclinical atherosclerotic disease despite the opportunity to investigate processes underlying this association. Therefore, we examined the relationship between coronary artery calcification as a sign of subclinical coronary atherosclerosis, socio-economic status and established cardiovascular risk factors in a healthy population. DESIGN: Cross-sectional. METHODS: In a population-based sample of 4487 men and women coronary artery calcification was assessed by electron beam computed tomography quantified by the Agatston score. Socio-economic status was assessed by two indicators, education and income. First, we investigated associations between the social measures and calcification. Second, we assessed the influence of cardiovascular risk factors on this association. RESULTS: After adjustment for age, men with 10 and less years of formal education had a 70% increase in calcification score compared with men with high education. The respective increase for women was 80%. For income the association was weaker (among men 20% higher for the lowest compared with the highest quartile; and among women 50% higher, respectively). Consecutive adjustment for cardiovascular risk factors significantly attenuated the observed association of socio-economic status with calcification. CONCLUSIONS: Social inequalities in coronary heart diseases seem to influence signs of subclinical coronary atherosclerosis as measured by coronary artery calcification. Importantly, cumulation of major cardiovascular risk factors in lower socio-economic groups accounted for a substantial part of this association. 相似文献