全文获取类型
收费全文 | 1077篇 |
免费 | 53篇 |
国内免费 | 5篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 65篇 |
妇产科学 | 15篇 |
基础医学 | 162篇 |
口腔科学 | 58篇 |
临床医学 | 84篇 |
内科学 | 193篇 |
皮肤病学 | 6篇 |
神经病学 | 41篇 |
特种医学 | 46篇 |
外科学 | 162篇 |
综合类 | 25篇 |
一般理论 | 2篇 |
预防医学 | 40篇 |
眼科学 | 77篇 |
药学 | 84篇 |
1篇 | |
中国医学 | 6篇 |
肿瘤学 | 55篇 |
出版年
2024年 | 2篇 |
2023年 | 11篇 |
2022年 | 26篇 |
2021年 | 77篇 |
2020年 | 52篇 |
2019年 | 50篇 |
2018年 | 54篇 |
2017年 | 40篇 |
2016年 | 44篇 |
2015年 | 40篇 |
2014年 | 45篇 |
2013年 | 85篇 |
2012年 | 104篇 |
2011年 | 86篇 |
2010年 | 49篇 |
2009年 | 27篇 |
2008年 | 49篇 |
2007年 | 48篇 |
2006年 | 61篇 |
2005年 | 43篇 |
2004年 | 45篇 |
2003年 | 32篇 |
2002年 | 13篇 |
2001年 | 1篇 |
1999年 | 2篇 |
1998年 | 5篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 7篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 2篇 |
1991年 | 1篇 |
1990年 | 4篇 |
1989年 | 3篇 |
1986年 | 1篇 |
1985年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1981年 | 2篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1961年 | 3篇 |
1960年 | 1篇 |
排序方式: 共有1135条查询结果,搜索用时 23 毫秒
61.
Avinash Ramyead Erich Studerus Michael Kometer Ulrike Heitz Ute Gschwandtner Peter Fuhr 《The world journal of biological psychiatry》2016,17(4):296-307
Objectives: In chronic schizophrenic psychoses, oscillatory abnormalities predominantly occur in prefrontal cortical regions and are associated with reduced communication across cortical areas. Nevertheless, it remains unclear whether similar alterations can be observed in patients with a first episode of psychosis (FEP), a state characterised by pathological features occurring in both late prodromal patients and initial phases of frank schizophrenic psychoses. Methods: We assessed resting-state electroencephalographic data of 31 antipsychotic-naïve FEP patients and 29 healthy controls (HC). We investigated the three-dimensional (3D) current source density (CSD) distribution and lagged phase synchronisation (LPS) of oscillations across small-scale and large-scale brain networks. We additionally investigated LPS relationships with clinical symptoms using linear mixed-effects models. Results: Compared to HC, FEP patients demonstrated abnormal CSD distributions in frontal areas of the brain; while decreased oscillations were found in the low frequencies, an increase was reported in the high frequencies (P?<?0.01). Patients also exhibited deviant LPS in the high frequencies, whose dynamics changed over increasing 3D cortico-cortical distances and increasing psychotic symptoms. Conclusions: These results indicate that in addition to prefrontal cortical abnormalities, altered synchronised neural oscillations are also present, suggesting possible disruptions in cortico-cortical communications. These findings provide new insights into the pathophysiological mechanisms of emerging schizophrenic psychoses. 相似文献
62.
63.
In vitro evidence that cytokine receptor signals are required for differentiation of double positive thymocytes into functionally mature CD8+ T cells 下载免费PDF全文
Yu Q Erman B Bhandoola A Sharrow SO Singer A 《The Journal of experimental medicine》2003,197(4):475-487
CD4(+)8(+) double positive (DP) thymocytes differentiate into CD4(+) and CD8(+) mature T cells in response to TCR signals. However, TCR signals that are initiated in DP thymocytes are unlikely to persist throughout all subsequent differentiation steps, suggesting that other signals must sustain thymocyte differentiation after TCR signaling has ceased. Using an in vitro experimental system, we now demonstrate that cytokine receptor signals, such as those transduced by IL-7 receptors, are required for differentiation of signaled DP thymocytes into functionally mature CD8(+) T cells as they: (a) up-regulate Bcl-2 expression to maintain thymocyte viability; (b) enhance CD4 gene silencing; (c) promote functional maturation;and (d) up-regulate surface expression of glucose transporter molecules, which improve nutrient uptake and increase metabolic activity. IL-7Rs appear to be unique among cytokine receptors in maintaining the viability of newly generated CD4(-)8(+) thymocytes, whereas several different cytokine receptors can provide the trophic/differentiative signals for subsequent CD8(+) thymocyte differentiation and maturation. Thus, cytokine receptors provide both survival and trophic/differentiative signals with varying degrees of redundancy that are required for differentiation of signaled DP thymocytes into functionally mature CD8(+) T cells. 相似文献
64.
Chetan V Kantharia R Y Prabhu A N Dalvi Abhijit Raut R D Bapat Avinash N Supe 《Tropical gastroenterology》2007,28(3):105-108
BACKGROUND AND AIMS: Pancreatic trauma is associated with high morbidity and mortality. Diagnosis is often difficult and surgery poses a formidable challenge. METHOD: Data from 17 patients of pancreatic trauma gathered from a prospectively maintained database were analysed and the following parameters were considered: mode of injury, diagnostic modalities, associated injury, grade of pancreatic trauma and management. Pancreatic trauma was graded from I through IV, as per Modified Lucas Classification. RESULTS: The median age was 39 years (range 19-61). The aetiology of pancreatic trauma was blunt abdominal trauma in 14 patients and penetrating injury in 3. Associated bowel injury was present in 4 cases (3 penetrating injury and 1 blunt trauma) and 1 case had associated vascular injury. 5 patients had grade I, 3 had grade II, 7 had grade III and 2 had grade IV pancreatic trauma. Contrast enhanced computed tomography scan was used to diagnose pancreatic trauma in all patients with blunt abdominal injury. Immediate diagnosis could be reached in only 4 (28.5%) patients. 7 patients responded to conservative treatment. Of the 10 patients who underwent surgery, 6 required it for the pancreas and the duodenum. (distal pancreatectomy with splenectomy-3, pylorus preserving pancreatoduodenectomy-1, debridement with external drainage-1, associated injuries-duodenum-1). Pancreatic fistula, recurrent pancreatitis and pseudocyst formation were seen in 3 (17.05%), 2 (11.7%) and 1 (5.4%) patient respectively. Death occurred in 4 cases (23.5%), 2 each in grades III and IV pancreatic trauma. CONCLUSIONS: Contrast enhanced computed tomography scan is a useful modality for diagnosing, grading and following up patients with pancreatic trauma. Although a majority of cases with pancreatic trauma respond to conservative treatment, patients with penetrating trauma, and associated bowel injury and higher grade pancreatic trauma require surgical intervention and are also associated with higher morbidity and mortality. 相似文献
65.
Stephen R. Lee Aoife Kilcoyne Avinash Kambadakone Ronald Arellano 《Abdominal imaging》2016,41(4):677-705
Percutaneous image-guided ablation is now commonly performed in many institutions for the treatment of hepatocellular carcinoma, liver metastases, and renal cell carcinoma in select patients. Accurate interpretation of post-ablation imaging is of supreme importance because treatment algorithms for these diseases rely heavily on imaging to guide management decisions. The purpose of this pictorial essay is to provide abdominal imagers with a review of the indications for percutaneous ablation in the abdomen, a basic overview of ablation modalities in clinical use today, the expected post-ablation imaging findings in the liver and kidney, and potential complications of hepatic and renal ablation procedures. 相似文献
66.
Nimish Rai Avinash Sharma Vinay Kulkarni Ram Godeshwar Pankaj Harkut 《Indian Journal of Thoracic and Cardiovascular Surgery》2010,26(3):216-218
Aortico Left Ventricular Tunnel (ALVT) is a rare congenital anomaly. It presents as an asymptomatic murmur to severe Aortic
Regurgitation (AR) and heart failure. Most of the patients have heart failure in first year of life. Patient rarely present
beyond second decade of life. Here we report a 42 year male with unusual type of ALVT, who presented with heart failure and
conduction disturbances. 相似文献
67.
68.
Frank M. Phillips Michael N. Tzermiadianos Leonard I. Voronov Robert M. Havey Gerard Carandang Susan M. Renner David M. Rosler Jorge A. Ochoa Avinash G. Patwardhan 《The spine journal》2009,9(1):96-102
Background contextLumbar fusion is traditionally used to restore stability after wide surgical decompression for spinal stenosis. The Total Facet Arthroplasty System (TFAS) is a motion-restoring implant suggested as an alternative to rigid fixation after complete facetectomy.PurposeTo investigate the effect of TFAS on the kinematics of the implanted and adjacent lumbar segments.Study designBiomechanical in vitro study.MethodsNine human lumbar spines (L1 to sacrum) were tested in flexion-extension (+8 to ?6 Nm), lateral bending (±6 Nm), and axial rotation (±5 Nm). Flexion-extension was tested under 400 N follower preload. Specimens were tested intact, after complete L3 laminectomy with L3–L4 facetectomy, after L3–L4 pedicle screw fixation, and after L3–L4 TFAS implantation. Range of motion (ROM) was assessed in all tested directions. Neutral zone and stiffness in flexion and extension were calculated to assess quality of motion.ResultsComplete laminectomy-facetectomy increased L3–L4 ROM compared with intact in flexion-extension (8.7±2.0 degrees to 12.2±3.2 degrees, p<.05) lateral bending (9.0±2.5 degrees to 12.6±3.2 degrees, p=.09), and axial rotation (3.8±2.7 degrees to 7.8±4.5 degrees p<.05). Pedicle screw fixation decreased ROM compared with intact, resulting in 1.7±0.5 degrees flexion-extension (p<.05), 3.3±1.4 degrees lateral bending (p<.05), and 1.8±0.6 degrees axial rotation (p=.09). TFAS restored intact ROM (p>.05) resulting in 7.9±2.1 degrees flexion-extension, 10.1±3.0 degrees lateral bending, and 4.7±1.6 degrees axial rotation. Fusion significantly increased the normalized ROM at all remaining lumbar segments, whereas TFAS implantation resulted in near-normal distribution of normalized ROM at the implanted and remaining lumbar segments. Flexion and extension stiffness in the high-flexibility zone decreased after facetectomy (p<.05) and increased after simulated fusion (p<.05). TFAS restored quality of motion parameters (load-displacement curves) to intact (p>.05). The quality of motion parameters for the whole lumbar spine mimicked L3–L4 segmental results.ConclusionsTFAS restored range and quality of motion at the operated segment to intact values and restored near-normal motion at the adjacent segments. 相似文献
69.
Avinash Sharma Vinay Kulkarni Saurabh Barde Shrikant Bobade Varun Bhargava Ram Ghodeshwar 《Indian Journal of Thoracic and Cardiovascular Surgery》2009,25(3):118-120
Submitral left ventricular aneurysm is a rare complex disorder, predominently found in African population. We report a case
of a 45 year male diagnosed to have a large submitral aneurysm, eroding the left circumflex artery, leading to severe mitral
regurgitation, severe tricuspid regurgitation and congestive heart failure. Surgical correction comprising of submitral aneurysmorraphy
with Teflon Felt, mitral valve replacement, modified DeVega’s tricuspid annuloplasty and ligation of left distal circumflex
was performed successfully in this case. 相似文献
70.
Monali Gajbhiye Jayendra Kesharwani Avinash Ingle Aniket Gade Mahendra Rai 《Nanomedicine : nanotechnology, biology, and medicine》2009,5(4):382-386
Silver nanoparticles (Ag-NPs) are known to have inhibitory and bactericidal effects. Resistance of fungal infections has emerged in recent years and is a major health problem. Here, we report the extracellular biosynthesis of Ag-NPs using a common fungus, Alternaria alternata. Also in this study, these nanoparticles were evaluated for their part in increasing the antifungal activity of fluconazole against Phoma glomerata, Phoma herbarum, Fusarium semitectum, Trichoderma sp., and Candida albicans. The antifungal activity of fluconazole was enhanced against the test fungi in the presence of Ag-NPs. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, which was confirmed from the increase in fold area of inhibition, followed by P. glomerata and Trichoderma sp., which showed less increase in the fold area, whereas no significant enhancement of activity was found against P. herbarum and F. semitectum.From the Clinical EditorThe antifungal activity of fluconazole was enhanced in presence of silver nanoparticles against the test fungi. Fluconazole in combination with Ag-NPs showed the maximum inhibition against C. albicans, followed by P. glomerata and Trichoderma sp. No significant enhancement of activity was found against P. herbarum and F. semitectum. 相似文献