全文获取类型
收费全文 | 983篇 |
免费 | 54篇 |
国内免费 | 4篇 |
专业分类
耳鼻咽喉 | 11篇 |
儿科学 | 17篇 |
妇产科学 | 15篇 |
基础医学 | 182篇 |
口腔科学 | 23篇 |
临床医学 | 108篇 |
内科学 | 178篇 |
皮肤病学 | 12篇 |
神经病学 | 91篇 |
特种医学 | 47篇 |
外国民族医学 | 1篇 |
外科学 | 149篇 |
综合类 | 15篇 |
预防医学 | 49篇 |
眼科学 | 27篇 |
药学 | 62篇 |
中国医学 | 11篇 |
肿瘤学 | 43篇 |
出版年
2024年 | 1篇 |
2023年 | 14篇 |
2022年 | 28篇 |
2021年 | 100篇 |
2020年 | 50篇 |
2019年 | 70篇 |
2018年 | 55篇 |
2017年 | 58篇 |
2016年 | 42篇 |
2015年 | 43篇 |
2014年 | 66篇 |
2013年 | 69篇 |
2012年 | 94篇 |
2011年 | 82篇 |
2010年 | 35篇 |
2009年 | 27篇 |
2008年 | 39篇 |
2007年 | 32篇 |
2006年 | 33篇 |
2005年 | 26篇 |
2004年 | 17篇 |
2003年 | 15篇 |
2002年 | 12篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1996年 | 4篇 |
1995年 | 1篇 |
1994年 | 2篇 |
1992年 | 3篇 |
1991年 | 2篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1980年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有1041条查询结果,搜索用时 78 毫秒
71.
72.
Adolescence spinal epidural abscess with neurological symptoms: case report,a lesson to be re-learnt
Jafar Ganjpour Sales Ali Tabrizi Asghar Elmi Jafar Soleimanpour Ehsan Gavidel 《Medical journal of the Islamic Republic of Iran》2013,27(1):38-41
Epidural abscess of the spinal column is a rare condition that can be fatal if left untreated. It promptly progresses and can cause neurologic paralysis, urinary retention or cauda equina syndrome. Compromised immune system that occurs in patients with diabetes mellitus, AIDS, chronic renal failure, alcoholism, or cancer is a predisposing factor. It mostly occurs in adults. Here we would like to report a case of spontaneous pyogenic lumbar epidural abscess with neurological deficit diagnosed in a 15 year old boy. We treated this case successfully with surgical microscopic decompression and drainage. 相似文献
73.
Kenneth A. Fetterly Hartwig R. Blume Michael J. Flynn Ehsan Samei 《Journal of digital imaging》2008,21(2):193-207
Consistent presentation of digital radiographic images at all locations within a medical center can help ensure a high level of patient care. Currently, liquid crystal displays (LCDs) are the electronic display technology of choice for viewing medical images. As the inherent luminance (and thereby perceived contrast) properties of different LCDs can vary substantially, calibration of the luminance response of these displays is required to ensure that observer perception of an image is consistent on all displays. The digital imaging and communication in medicine (DICOM) grayscale standard display function (GSDF) defines the luminance response of a display such that an observer's perception of image contrast is consistent throughout the pixel value range of a displayed image. The main purpose of this work is to review the theoretical and practical aspects of calibration of LCDs to the GSDF. Included herein is a review of LCD technology, principles of calibration, and other practical aspects related to calibration and observer perception of images presented on LCDs. Both grayscale and color displays are considered, and the influence of ambient light on calibration and perception is discussed. 相似文献
74.
Most patients are eligible for an alternative to conventional whole breast irradiation for early‐stage breast cancer: A National Cancer Database Analysis
下载免费PDF全文
![点击此处可从《The breast journal》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Ehsan H. Balagamwala MD Bindu V. Manyam MD Charles Marc Leyrer MD Naveen Karthik Timothy Smile BS Rahul D. Tendulkar MD Sheen Cherian MD Diane Radford MD FACS FRCSEd Zahraa Al‐Hilli MD Frank Vicini MD Chirag Shah MD 《The breast journal》2018,24(5):806-810
We evaluated the proportion of patients eligible for alternatives to standard whole breast irradiation (WBI) following breast‐conserving surgery using the National Cancer Database (NCDB). Using the 2016 dataset, Stage I‐III patients were identified. Eligibility for hypofractionated WBI (HFRT), accelerated partial breast irradiation (APBI) and endocrine therapy (ET‐alone) was defined using eligibility from large clinical trials as well as consensus guidelines. For patients with pN0 breast cancer, 20.6% and 37.0% were eligible for ET‐alone based on the CALGB 9343/PRIME‐II trials, respectively. In terms of HFRT, 72.5% and 50.4% were eligible based on IMPORT LOW/ASTRO HFRT guidelines, respectively. Based on IMPORT LOW/GEC‐ESTRO trial/ASTRO guidelines/ABS guidelines/GEC‐ESTRO guidelines, 72.5%, 86.1%, 39.0%, 72.5%, 45.7%, respectively, were eligible for APBI. Of those who qualify for HFRT per ASTRO guidelines, approximately 90% were eligible for APBI and 50% for ET‐alone. This analysis shows that a large proportion of patients with node‐negative breast cancer are eligible for HFRT, APBI and/or ET‐alone after breast‐conserving surgery. 相似文献
75.
Emma C. Scott Parameswaran Hari Sathish Kumar Raphael Fraser Omar Davila Nina Shah Robert Peter Gale Miguel Angel Diaz Vaibhav Agrawal Robert F. Cornell Siddhartha Ganguly Gorgun Akpek Cesar Freytes Shahrukh Hashmi Ehsan Malek Rammurti T. Kamble Hillard Lazarus Melhem Solh Anita DSouza 《Biology of blood and marrow transplantation》2018,24(12):2443-2449
The Revised International Staging System (R-ISS) and the International Myeloma Working Group 2014 (IMWG 2014) are newer staging systems used to prognosticate multiple myeloma (MM) outcomes. We hypothesized that these would provide better prognostic differentiation for newly diagnosed multiple myeloma (MM) compared with ISS. We analyzed the Center for International Blood and Marrow Transplant Research database from 2008 to 2014 to compare the 3 systems (N?=?628) among newly diagnosed MM patients undergoing upfront autologous hematopoietic cell transplantation (AHCT). The median follow-up of survivors was 48 (range, 3 to 99) months. The R-ISS provided the greatest differentiation between survival curves for each stage (for overall survival [OS], the differentiation was 1.74 using the R-ISS, 1.58 using ISS, and 1.60 using the IMWG 2014) . Univariate analyses at 3 years for OS showed R-ISS I at 88% (95% confidence interval [CI], 83% to 93%), II at 75% (95% CI, 70% to 80%), and III at 56% (95% CI, 3% to 69%; P < .001). An integrated Brier score function demonstrated the R-ISS had the best prediction for PFS, though all systems had similar prediction for OS. Among available systems, the R-ISS is the most optimal among available prognostic tools for newly diagnosed MM undergoing AHCT. We recommend that serum lactate dehydrogenase and cytogenetic data be performed on every MM patient at diagnosis to allow accurate prognostication. 相似文献
76.
Mutation in ADORA1 identified as likely cause of early‐onset parkinsonism and cognitive dysfunction
下载免费PDF全文
![点击此处可从《Movement disorders》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Elham Jaberi PhD Mohammad Rohani MD Gholam Ali Shahidi MD Shahriar Nafissi MD Ehsan Arefian PhD Masoud Soleimani PhD Abolfazl Moghadam MS Mohsen Karimi Arzenani PhD Farid Keramatian MS Brandy Klotzle PhD Jian‐Bing Fan PhD Casey Turk PhD Frank Steemers PhD Elahe Elahi PhD 《Movement disorders》2016,31(7):1004-1011
77.
David N. Ranney Morgan L. Cox Babatunde A. Yerokun Ehsan Benrashid Richard L. McCann G. Chad Hughes 《Journal of vascular surgery》2018,67(2):363-368
Objective
Since thoracic endovascular aortic repair (TEVAR) received U.S. Food and Drug Administration approval for the treatment of descending thoracic aneurysms in March 2005, excellent 30-day and midterm outcomes have been described. However, data on long-term outcomes are lacking with Medicare data suggesting that TEVAR has worse late survival compared with open descending repair. As such, the purpose of this study was to examine the long-term outcomes for on-label use of TEVAR for repair of descending thoracic aneurysms.Methods
Of 579 patients undergoing TEVAR between March 2005 and April 2016 at a single referral center for aortic surgery, 192 (33.2%) were performed for a descending thoracic aneurysm indication in accordance with the device instructions for use, including 106 fusiform (55.2%), 80 saccular (41.7%), and 6 with both saccular and fusiform (3.1%) aneurysms. All aneurysms were located distal to the left subclavian artery and proximal to the celiac axis, and hybrid procedures including arch or visceral debranching were excluded with the exception of left carotid-subclavian artery bypass. Aortic dissection and intramural hematoma as indications for TEVAR were also excluded. Primary 30-day and in-hospital outcomes included mortality, stroke, need for new permanent dialysis, and permanent paraparesis or paraplegia. Primary long-term outcomes included survival and rate of reintervention secondary to endoleak. The Kaplan-Meier method was used to estimate long-term overall and aorta-specific survivals.Results
The mean age was 71.1 ± 10.4 years. All aneurysms in this series were degenerative in nature and no patients with a connective tissue disorder were included. The mean aortic diameter was 5.9 ± 1.5 cm at time of intervention. Rates of 30-day and in-hospital mortality, stroke, permanent dialysis, and permanent paraparesis and paraplegia were 4.7%, 2.1%, 0.5%, and 0.5%, respectively. At a mean follow-up of 69 ± 44 months (range, 3-141 months), there were 68 late deaths (35.4%), two of which were due to aortic rupture. Overall and aorta-specific survivals at 141 months (11.8 years) were 45.7% and 96.2%, respectively. Endovascular reintervention was required in 14 patients (7.3%) owing to type I (n = 10), type II (n = 2), and type III (n = 2) endoleak, all of which subsequently resolved. No patient required open reintervention for any cause.Conclusions
Long-term (12-year) aorta-specific survival after on-label endovascular repair of degenerative descending thoracic aneurysms in nonsyndromic patients is excellent (96%) with sustained protection from rupture, and a low rate of reintervention owing to endoleak (7%). Endovascular repair should be considered the treatment of choice for this pathology. 相似文献78.
79.
Ahmadzadeh R Saboory E Roshan-Milani S Pilehvarian AA 《Developmental psychobiology》2011,53(8):806-812
Stress during gestation can result in early and long-term developmental aberrations. This study aimed to assess the impact of prenatal restraint or predator stress on pilocarpine-induced epileptic behavior. Pregnant rats were exposed to stressors on gestational days 15, 16, and 17. Restraint stress consisted of daily restraint of the dam. During predator stress, caged rats were exposed to a cat in a cage. On postnatal day 25, male pups were injected with pilocarpine and the behavior of each rat was observed. Prenatal stress led to low birth weight and increased blood corticosterone levels. Both stressors significantly potentiated pilocarpine-induced seizures. Predator-stressed pups exhibited significantly severe tonic-clonic seizures compared with restraint-stressed animals. These data emphasize the impact of prenatal stress on fetal growth, and neural and endocrine function. The results also suggest that psychosocial stressors have a greater impact on neural and endocrine function than physical stressors do. 相似文献
80.
Dual-energy contrast-enhanced breast tomosynthesis is a promising technique to obtain three-dimensional functional information from the breast with high resolution and speed. To optimize this new method, this study searched for the beam quality that maximized image quality in terms of mass detection performance. A digital tomosynthesis system was modeled using a fast ray-tracing algorithm, which created simulated projection images by tracking photons through a voxelized anatomical breast phantom containing iodinated lesions. The single-energy images were combined into dual-energy images through a weighted log subtraction process. The weighting factor was optimized to minimize anatomical noise, while the dose distribution was chosen to minimize quantum noise. The dual-energy images were analyzed for the signal difference to noise ratio (SdNR) of iodinated masses. The fast ray-tracing explored 523?776 dual-energy combinations to identify which yields optimum mass SdNR. The ray-tracing results were verified using a Monte Carlo model for a breast tomosynthesis system with a selenium-based flat-panel detector. The projection images from our voxelized breast phantom were obtained at a constant total glandular dose. The projections were combined using weighted log subtraction and reconstructed using commercial reconstruction software. The lesion SdNR was measured in the central reconstructed slice. The SdNR performance varied markedly across the kVp and filtration space. Ray-tracing results indicated that the mass SdNR was maximized with a high-energy tungsten beam at 49 kVp with 92.5 μm of copper filtration and a low-energy tungsten beam at 49 kVp with 95 μm of tin filtration. This result was consistent with Monte Carlo findings. This mammographic technique led to a mass SdNR of 0.92 ± 0.03 in the projections and 3.68 ± 0.19 in the reconstructed slices. These values were markedly higher than those for non-optimized techniques. Our findings indicate that dual-energy breast tomosynthesis can be performed optimally at 49 kVp with alternative copper and tin filters, with reconstruction following weighted subtraction. The optimum technique provides best visibility of iodine against structured breast background in dual-energy contrast-enhanced breast tomosynthesis. 相似文献