全文获取类型
收费全文 | 1028篇 |
免费 | 47篇 |
国内免费 | 9篇 |
专业分类
耳鼻咽喉 | 5篇 |
儿科学 | 22篇 |
妇产科学 | 3篇 |
基础医学 | 101篇 |
口腔科学 | 12篇 |
临床医学 | 83篇 |
内科学 | 224篇 |
皮肤病学 | 119篇 |
神经病学 | 149篇 |
特种医学 | 46篇 |
外科学 | 109篇 |
综合类 | 6篇 |
预防医学 | 30篇 |
眼科学 | 53篇 |
药学 | 51篇 |
中国医学 | 1篇 |
肿瘤学 | 70篇 |
出版年
2022年 | 6篇 |
2021年 | 7篇 |
2020年 | 10篇 |
2019年 | 8篇 |
2018年 | 8篇 |
2017年 | 15篇 |
2016年 | 24篇 |
2015年 | 30篇 |
2014年 | 28篇 |
2013年 | 31篇 |
2012年 | 49篇 |
2011年 | 45篇 |
2010年 | 32篇 |
2009年 | 43篇 |
2008年 | 55篇 |
2007年 | 65篇 |
2006年 | 75篇 |
2005年 | 75篇 |
2004年 | 76篇 |
2003年 | 55篇 |
2002年 | 80篇 |
2001年 | 20篇 |
2000年 | 21篇 |
1999年 | 24篇 |
1998年 | 14篇 |
1997年 | 10篇 |
1996年 | 8篇 |
1995年 | 12篇 |
1994年 | 11篇 |
1992年 | 5篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 8篇 |
1988年 | 4篇 |
1987年 | 6篇 |
1986年 | 8篇 |
1985年 | 11篇 |
1984年 | 7篇 |
1983年 | 9篇 |
1982年 | 4篇 |
1979年 | 5篇 |
1978年 | 4篇 |
1977年 | 9篇 |
1973年 | 5篇 |
1972年 | 3篇 |
1971年 | 6篇 |
1968年 | 4篇 |
1965年 | 3篇 |
1956年 | 4篇 |
1955年 | 3篇 |
排序方式: 共有1084条查询结果,搜索用时 15 毫秒
31.
Arne J. Venjakob Stephan Vogt Klaus Stöckl Thomas Tischer Philipp J. Jost Eckart Thein Andreas B. Imhoff Hermann Anetzberger 《Journal of orthopaedic research》2013,31(11):1820-1827
Local cooling is very common after bone and joint surgery. Therefore the knowledge of bone blood flow during local cooling is of substantial interest. Previous studies revealed that hypothermia leads to vasoconstriction followed by decreased blood flow levels. The aim of this study was to characterize if local cooling is capable of inducing reduced blood flow in bone tissue using a stepwise‐reduced temperature protocol in experimental rabbits. To examine bone blood flow we utilized the fluorescent microsphere (FM) method. In New Zealand white rabbits one randomly chosen hind limb was cooled stepwise from 32 to 2°C, whereas the contra lateral hind limb served as control. Injection of microspheres was performed after stabilization of bone and muscle temperature at each temperature level. Bones were removed, dissected and fluorescence intensity was determined to calculate blood flow values. We found that blood flow of all cooled regions decreased relative to the applied external temperature. At maximum cooling blood flow was almost completely disrupted, indicating local cooling as powerful regulatory mechanism for regional bone blood flow (RBBF). Postoperative cooling therefore may lead to strongly decreased bone blood flow values. As a result external cooling has capacity to both diminish bone healing and reduce bleeding complications. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1820–1827, 2013 相似文献
32.
Stephan Vogt Arne J. Venjakob Klaus Stöckl Thomas Tischer Philipp J. Jost Andreas B. Imhoff Eckart Thein Hermann Anetzberger 《Archives of orthopaedic and trauma surgery》2013,133(9):1233-1241
Background
Blood flow in various organs is determined by an autoregulatory mechanism that guarantees constant organ perfusion over a wide range of arterial blood pressure changes. This physiological principle has been proven for the kidney, brain and intestinal tract, but so far not for bone. This study was carried out to determine whether there is an autoregulatory mechanism of bone or not.Methods
The fluorescent microsphere reference sample method was used to determine blood flow within the bone and kidneys. Eight anesthetized female New Zealand rabbits received left ventricular injections of fluorescent microspheres over a wide range of arterial pressure levels prior to removal of kidney, femur and tibia. Blood flow values were calculated by measurement of fluorescence intensity in kidney and bone and correlated to fluorescence intensity in the peripheral blood (reference sample).Results
Despite a reduction of mean arterial pressure from 100 to 80 mmHg bone blood flow remained constant. Further reduction of mean arterial pressure results in a linear decrease in bone blood flow.Conclusion
The correlation between arterial pressure and organ perfusion in the bone is similar to blood flow within the kidney, indicating the presence of an autoregulated blood flow mechanism within the bone tissue. 相似文献33.
Andreas Wahl Ingo Paetsch Albrecht Gollesch Stefan Roethemeyer Daniela Foell Rolf Gebker Holger Langreck Christoph Klein Eckart Fleck Eike Nagel 《European heart journal》2004,25(14):1230-1236
AIMS: To determine the safety of high-dose dobutamine-atropine stress cardiovascular magnetic resonance (stress-CMR), which recently emerged as a highly accurate modality for diagnosis of inducible myocardial ischaemia. METHOD AND RESULTS: From 1997 to 2002, 1000 consecutive stress-CMR examinations were performed. Images were acquired at rest and during a high-dose dobutamine-atropine protocol in 3 short-axis, a 4- and a 2-chamber view. Stress testing was discontinued when > or =85% of age-predicted heart rate was reached, on patient request, maximum pharmacologic infusion, or when new or worsening wall motion abnormalities, severe angina, dyspnoea, increase or decrease in blood pressure, or severe arrhythmias occurred. Stress-CMR was successfully performed in all but four patients (0.4%; insufficient ECG-triggering). Target heart rate was not reached in 95 cases (9.5%), due to maximum pharmacologic infusion in submaximal negative examinations in 21 cases (2.1%), and limiting side effects in 74 (7.4%). Side effects included one case (0.1%) of sustained and four cases (0.4%) of non-sustained ventricular tachycardia, 16 cases (1.6%) of atrial fibrillation, and two cases (0.2%) of transient second degree AV block. CONCLUSION: The safety profile of stress-CMR is similar to other methodologies using dobutamine infusions. Patients must be closely monitored, and resuscitation equipment and trained personnel must be available. 相似文献
34.
Anke Steinmetz Andreas Stang Malte Kornhuber Marc Röllinghoff Karl-Stefan Delank Eckart Altenmüller 《International archives of occupational and environmental health》2014,87(7):783-792
Objectives
Data concerning embouchure problems in professional brass players are scarce. Embouchure problems can potentially lead to focal dystonia. The aim of this study was to investigate the frequency of distinct embouchure problems in professional brass players. Furthermore, the frequency of “cramping”, a distinct symptom of embouchure dystonia, was evaluated in the context of established embouchure dystonia risk factors.Methods
Five hundred and eighty-five professional brass players participated in a cross-sectional study concerning embouchure problems. A self-administered questionnaire was developed to evaluate embouchure fatigue, embouchure disorders and their consequences. To study the association between risk factors and cramping (a symptom of embouchure dystonia), a log-binomial regression analysis was conducted, enabling estimation of prevalence ratios (PR) and 95 % confidence intervals (95 % CI).Results
Thirty percent (95 % CI 25.9–33.3) reported embouchure fatigue. The relative frequency of embouchure disorders was 59 % (95 % CI 54.6–63.6), with 26 % (95 % CI 22.4–29.5) reporting embouchure cramping. Embouchure disorders resulted in sick leave in 16 % (95 % CI 12.7–20.6). Female brass players (PR 2.0, 95 % CI 0.98–3.98) and musicians with a prior change in their embouchure (PR 2.4, 95 % CI 1.38–4.05) or breathing technique (PR 2.2, 95 % CI 1.25–3.72) and musicians with embouchure fatigue (PR 1.9, 95 % CI 1.18–2.93) presented more frequently with embouchure cramping than musicians with other or without risk factors.Conclusion
This study shows a high relative frequency of embouchure problems in professional brass players. Given that embouchure dystonia is often preceded by embouchure problems, these findings may assist in gaining further insight into the characteristics of embouchure dystonia and the development of preventive strategies. 相似文献35.
Beate Roxane Jaeger Eckart Kreuzer Andreas Knez Andreas Leber Peter Überfuhr Monika Brner Petra Milz Bruno Reichart Dietrich Seidel 《Therapeutic apheresis and dialysis : official peer-reviewed journal of the International Society for Apheresis, the Japanese Society for Apheresis, the Japanese Society for Dialysis Therapy》2002,6(5):394-398
Abstract: We report the first experiences with HELP apheresis as an emergency treatment for acute cardiovascular syndromes; two patients who were not eligible for lysis therapy and catheter intervention were treated with HELP apheresis instead. Both patients had a most severe, generalized atherosclerosis and reached the hospital too late for conventional measures. In both cases, the use of the apheresis dramatically improved the clinical situation to such an extent that the possibilities of this apheresis system urge further investigation. 相似文献
36.
Vishal Thakur MD Keshavamurthy Vinay MD DNB Eckart Haneke MD PhD 《International journal of dermatology》2020,59(6):656-669
Onychocryptosis, or ingrown toenail, is a frequent, painful condition affecting young individuals. Controversies still exist regarding its etiopathogenesis and treatment options, including conservative and surgical techniques. The choice of treatment method depends on the stage of disease as conservative measures are mostly effective in early stages and surgical procedures are required in the later stages. Among surgical techniques, phenol cauterization of lateral nail matrix has been the most effective, safe, and commonly performed method. Other more destructive surgical procedures are rarely done nowadays. In this review, we briefly discuss the etiopathogenesis, clinical features, and different treatment options of ingrown toenail. 相似文献
37.
Christian Grieser Ingo G. Steffen Incken-Birthe Kramme Hendrik Bläker Ergin Kilic Carmen Maria Perez Fernandez Daniel Seehofer Eckart Schott Bernd Hamm Timm Denecke 《European radiology》2014,24(6):1339-1348
Objectives
Evaluation of enhancement characteristics of histopathologically confirmed focal nodular hyperplasias (FNHs) and hepatocellular adenomas (HCAs) with gadoxetic acid-enhanced MRI.Methods
Sixty-eight patients with 115 histopathologically proven lesions (FNHs, n?=?44; HCAs, n?=?71) examined with gadoxetic acid-enhanced MRI were retrospectively enrolled (standard of reference: surgical resection, n?=?53 patients (lesions: FNHs, n?=?37; HCAs, n?=?53); biopsy, n?=?15 (lesions: FNHs, n?=?7; HCAs, n?=?18)). Two radiologists evaluated all MR images regarding morphological features as well as the vascular and hepatocyte-specific enhancement in consensus.Results
For the hepatobiliary phase, relative enhancement of the lesions and lesion to liver enhancement were significantly lower for HCAs (mean, 48.7 (±48.4) % and 49.4 (±33.9) %) compared to FNHs (159.3 (±92.5) %; and 151.7 (±79) %; accuracy of 89 % and 90 %, respectively; P?<?0.001). Visual strong uptake of FNHs vs. hypointensity of HCAs in the hepatobiliary phase resulted in an accuracy of 92 %. This parameter was superior to all other morphological and dynamic vascular criteria alone and in combination (accuracy, 54–85 %).Conclusions
For differentiation of FNHs and HCAs by means of MRI, gadoxetic acid uptake in the hepatobiliary phase was found to be superior to all other criteria alone and in combination.Key Points
? EOB-MRI is well suited to differentiate FNHs and hepatocellular adenomas. ? For this purpose hepatobiliary phase is superior to unenhanced and dynamic imaging. ? Hepatobiliary phase (peripheral) hyper- or isointensity is typical for FNH. ? Hepatobiliary phase hypointensity is typical for hepatocellular adenomas. ? EOB-MRI helps to avoid misinterpretations of benign hepatocellular lesions. 相似文献38.
Nadine Schlichting Tatiana Kartashova Michael Wiesing Eckart Zimmermann 《Journal of vision》2022,22(2)
Complex, goal-directed and time-critical movements require the processing of temporal features in sensory information as well as the fine-tuned temporal interplay of several effectors. Temporal estimates used to produce such behavior may thus be obtained through perceptual or motor processes. To disentangle the two options, we tested whether adaptation to a temporal perturbation in an interval reproduction task transfers to interval reproduction tasks with varying sensory information (visual appearance of targets, modality, and virtual reality [VR] environment or real-world) or varying movement types (continuous arm movements or brief clicking movements). Halfway through the experiments we introduced a temporal perturbation, such that continuous pointing movements were artificially slowed down in VR, causing participants to adapt their behavior to sustain performance. In four experiments, we found that sensorimotor adaptation to temporal perturbations is independent of environment context and movement type, but modality specific. Our findings suggest that motor errors induced by temporal sensorimotor adaptation affect the modality specific perceptual processing of temporal estimates. 相似文献
39.
Anna Dondzillo Kurt Stzler Heinz Horstmann Wilko D. Altrock Eckart D. Gundelfinger Thomas Kuner 《The Journal of comparative neurology》2010,518(7):1008-1029
Bassoon and Piccolo contribute to the cytomatrix of active zones (AZ), the sites of neurotransmitter release in nerve terminals. Here, we examined the 3D localization of Bassoon and Piccolo in the rat calyx of Held between postnatal days 9 and 21, the period of hearing onset characterized by pronounced structural and functional changes. Bassoon and Piccolo were identified by immunohistochemistry (IHC) on slices of the brainstem harboring calyces labeled with membrane‐anchored green fluorescent protein (mGFP). By using confocal microscopy and 3D reconstructions, we examined the distribution of Bassoon and Piccolo in calyces delineated by mGFP. This allowed us to discriminate calyceal IHC signals from noncalyceal signals located in the spaces between the calyceal stalks, which could mimic a calyx‐like distribution. We found that both proteins were arranged in clusters resembling the size of AZs. These clusters were located along the presynaptic membrane facing the principal cell, close to or overlapping with synaptic vesicle (SV) clusters. Only about 60% of Bassoon and Piccolo clusters overlapped, whereas the remaining clusters contained predominantly Bassoon or Piccolo, suggesting differential targeting of these proteins within a single nerve terminal and potentially heterogeneous AZs functional properties. The total number of Bassoon and Piccolo clusters, which may approximate the number of AZs, was 405 ± 35 at P9 and 601 ± 45 at P21 (mean ± SEM, n = 12). Normalized to calyx volume at P9 and P21, the density of clusters was similar, suggesting that the absolute number of clusters, not density, may contribute to the functional maturation associated with hearing onset. J. Comp. Neurol. 518:1008–1029, 2010. © 2009 Wiley‐Liss, Inc. 相似文献
40.
Pattern of serum autoantibodies allows accurate distinction between a tumor and pathologies of the same organ 总被引:1,自引:0,他引:1
Nicole Ludwig Andreas Keller Nicole Comtesse Stefanie Rheinheimer Christian Pallasch Ulrike Fischer Klaus Fassbender Wolf Ingo Steudel Hans-Peter Lenhof Eckart Meese 《Clinical cancer research》2008,14(15):4767-4774
PURPOSE: Recent studies impressively showed the diagnostic potential of seroreactivity patterns for different tumor types, offering the prospect for low-cost screening of numerous tumor types simultaneously. One of the major challenges toward this goal is to prove that seroreactivity profiles do not only allow for identifying a tumor but also allow for distinguishing tumors from other pathologies of the same organ. EXPERIMENTAL DESIGN: We chose glioma as a model system and tested 325 sera (88 glioma, 95 intracranial tumors, 60 other brain pathologies, and 82 healthy controls) for seroreactivity on a panel of 35 antigens. RESULTS: We were able to discriminate between glioma and all other sera with cross-validated specificity of 86.1%, sensitivity of 85.2%, and accuracy of 85.8%. We obtained comparably good results for the separation of glioma versus nontumor brain pathologies and glioma versus other intracranial tumors. CONCLUSION: Our study provides first evidence that seroreactivity patterns allow for an accurate discrimination between a tumor and pathologies of the same organ even between different tumor types of the same organ. 相似文献