全文获取类型
收费全文 | 9147篇 |
免费 | 712篇 |
国内免费 | 44篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 250篇 |
妇产科学 | 55篇 |
基础医学 | 1176篇 |
口腔科学 | 176篇 |
临床医学 | 949篇 |
内科学 | 1895篇 |
皮肤病学 | 187篇 |
神经病学 | 1196篇 |
特种医学 | 684篇 |
外科学 | 1600篇 |
综合类 | 47篇 |
一般理论 | 4篇 |
预防医学 | 441篇 |
眼科学 | 157篇 |
药学 | 420篇 |
中国医学 | 6篇 |
肿瘤学 | 584篇 |
出版年
2024年 | 23篇 |
2023年 | 130篇 |
2022年 | 207篇 |
2021年 | 388篇 |
2020年 | 250篇 |
2019年 | 288篇 |
2018年 | 332篇 |
2017年 | 291篇 |
2016年 | 360篇 |
2015年 | 351篇 |
2014年 | 468篇 |
2013年 | 555篇 |
2012年 | 841篇 |
2011年 | 831篇 |
2010年 | 469篇 |
2009年 | 393篇 |
2008年 | 592篇 |
2007年 | 597篇 |
2006年 | 493篇 |
2005年 | 371篇 |
2004年 | 339篇 |
2003年 | 292篇 |
2002年 | 287篇 |
2001年 | 91篇 |
2000年 | 59篇 |
1999年 | 67篇 |
1998年 | 46篇 |
1997年 | 21篇 |
1996年 | 23篇 |
1995年 | 19篇 |
1994年 | 17篇 |
1993年 | 19篇 |
1992年 | 40篇 |
1991年 | 28篇 |
1990年 | 32篇 |
1989年 | 27篇 |
1988年 | 26篇 |
1987年 | 26篇 |
1986年 | 15篇 |
1985年 | 20篇 |
1984年 | 8篇 |
1983年 | 12篇 |
1982年 | 11篇 |
1981年 | 8篇 |
1979年 | 11篇 |
1978年 | 14篇 |
1976年 | 11篇 |
1973年 | 10篇 |
1972年 | 12篇 |
1922年 | 14篇 |
排序方式: 共有9903条查询结果,搜索用时 15 毫秒
81.
82.
83.
84.
Christian Dejaco Tobias De Zordo Daniel Heber Wolfgang Hartung Rainer Lipp Andre Lutfi Marton Magyar Dorothea Zauner Angelika Lackner Christina Duftner Jutta Horwath-Winter Winfried B. Graninger Josef Hermann 《Ultrasound in medicine & biology》2014,40(12):2759-2767
The purpose of this study was to investigate the value of real-time sonoelastography (RTS) of salivary glands for the diagnosis and assessment of glandular damage in primary Sjögren’s syndrome (pSS). After institutional review board approval, 45 pSS patients, 24 sicca patients and 11 healthy controls were investigated prospectively. Questionnaires were completed and Saxon and Schirmer tests and routine blood tests carried out in all patients. All patients underwent B-mode ultrasonography and RTS of parotid and submandibular glands. Abnormal findings were graded from 0 to 48 and from 0 to 16, respectively. Sialoscintigraphy was done according to a routine protocol; scoring ranged from 0 to 12. Statistical analysis comprised receiver operating characteristic curve and multivariate regression analysis. Patients with pSS had higher B-mode (median score = 25 [range: 2–44] vs. 9 [1–20], p < 0.001) and RTS (6.5 [2–13] versus 4 [1–9], p < 0.001) scores than controls with sicca syndrome, yielding areas under the curve of 0.83 and 0.85 (p < 0.05 each), respectively for pSS diagnosis. In cases with an inconclusive B-mode ultrasonography result, RTS (cutoff score: ≥6) led to a sensitive (66.7%) and specific (85.7%) classification of patients and sicca controls. In multivariate regression analysis, RTS (regression coefficient = –0.48, p = 0.005), but not B-mode ultrasonography, reflected impaired salivary gland function according to the Saxon test, whereas none of the subjective measures of dryness or discomfort were related to ultrasonography results. B-mode and RTS results were both associated with sialoscintigraphy scores (regression coefficient = 0.66, p < 0.001, and regression coefficient = 0.55, p = 0.001, respectively). Reproducibility of B-mode ultrasonography and RTS was good, with intra-class correlation coefficients of 0.93 (95% confidence interval: 0.57–0.98) and 0.93 (95% confidence interval: 0.79–0.98), respectively. In summary, RTS might be a useful adjunct to B-mode ultrasonography for diagnosis and assessment of salivary gland impairment in primary Sjögren’s syndrome. 相似文献
85.
86.
Janine Bayer Pia Bandurski Tobias Sommer 《The European journal of neuroscience》2013,38(10):3519-3526
Estradiol and progesterone interact with the dopaminergic and other neurotransmitter systems that are involved in the processing of rewards. On the systems level, these hormones modulate responses to stimulants as well as neuronal activity related to the anticipation of monetary gains. As different mechanisms might underlie the processing of gains and losses, the current study aims to investigate whether neural correlates of gain and loss anticipation are differentially modulated by menstrual cycle phases. Therefore, young, naturally cycling women were examined by means of functional neuroimaging during performing a modified version of the ‘Monetary Incentive Delay’ task in the early follicular and in the luteal menstrual cycle phase. During the low hormone early follicular phase, the anticipation of high vs. low gains and losses was associated with activity in a largely overlapping network of brain areas. However, high hormone levels in the luteal phase affected brain activity in these areas differentially during the anticipation of high vs. low gains and losses. In particular, the orbitofrontal cortex showed a reduced sensitivity to gain magnitude, whereas the ventral striatum and the anterior cingulate showed a reduced sensitivity to loss magnitude. In summary, the high amount of progesterone and estradiol in the luteal phase decreased activity related to the anticipation of monetary gains and losses in different brain areas, suggesting that hormones modulate different processes during the anticipation of gain and loss magnitude. 相似文献
87.
Tobias Skjelbred Thomas Hadberg Lynge Jakob Nielsen Bo Gregers Winkel Jacob Tfelt-Hansen 《Trends in Cardiovascular Medicine》2021,31(2):119-124
Sudden Cardiac Death (SCD) is a leading cause of death among persons in their youth and early middle-age. To prevent SCD it is crucial to identify persons at high-risk of SCD. Knowledge of symptoms and medical contact prior to SCD could potentially aid in the identification of high-risk persons in the general population who would benefit from further investigation. This review aims to summarize the current knowledge of symptoms and healthcare contact preceding SCD in persons aged 1–49 years, and to explore how the symptoms differ according to SCD cause and age of the deceased.There was a high frequency of both cardiac and non-specific symptoms prior to SCD. Additionally, many SCD victims contacted the healthcare system prior to death on the basis of their symptoms and only a few were diagnosed with cardiovascular disease. This information underlines that young persons reporting potential cardiac symptoms should also be thoroughly examined. Furthermore, such symptoms could be used in combination with other easily accessible information in non-invasive prediction models aiming at identifying persons at high risk of SCD that would benefit from further investigation and possibly treatment. 相似文献
88.
Concomitant MDS with isolated 5q deletion and MGUS: case report and review of molecular aspects 下载免费PDF全文
Florian Nolte Maximilian Mossner Johann‐Christoph Jann Daniel Nowak Tobias Boch Nadine Zoe Müller Wolf‐Karsten Hofmann Georgia Metzgeroth 《European journal of haematology》2017,98(3):302-310
Patients with monoclonal gammopathy of undetermined significance (MGUS) have a higher risk for the development of concomitant primary cancers such as multiple myeloma (MM) and myelodysplastic syndrome (MDS). We report the case of patient initially suffering from MGUS of the IgG lambda subtype for more than 10 yr, which evolved to MM and MDS with deletion (5q) with severe pancytopenia. Due to pancytopenia, he received dose‐reduced treatment with lenalidomide and dexamethasone. He achieved an ongoing transfusion independency after about 1 month of treatment. Bone marrow taken 14 months after start of treatment showed a complete cytogenetic response of the del(5q) clone and a plasma cell infiltration below 5%. In contrast to the development of MM in MGUS patients, the subsequent occurrence of MDS after diagnosis of MGUS is infrequent. Moreover, the biological association of MDS with MGUS is not sufficiently understood, but the non‐treatment‐related occurrence supports the pathogenetic role of pre‐existing alterations of stem cells. Here, we summarize data on concomitant MDS and MGUS/MM with particular emphasis on molecular aspects. 相似文献
89.
90.
Kristine H. Østergaard Ulrik T. Baandrup Tobias Wang Mads F. Bertelsen Johnnie B. Andersen Morten Smerup Jens R. Nyengaard 《Anatomical record (Hoboken, N.J. : 2007)》2013,296(4):611-621
The giraffe heart has a relative mass similar to other mammals, but generates twice the blood pressure to overcome the gravitational challenge of perfusing the cerebral circulation. To provide insight as to how the giraffe left ventricle (LV) is structurally adapted to tackle such a high afterload, we performed a quantitative structural study of the LV myocardium in young and adult giraffe hearts. Tissue samples were collected from young and adult giraffe LV. Design‐based stereology was used to obtain unbiased estimates of numbers and sizes of cardiomyocytes, nuclei and capillaries. The numerical density of myocyte nuclei was 120 × 103 mm?3 in the adult and 504 × 103 mm?3 in the young LV. The total number (N) of myocyte nuclei was 1.3 × 1011 in the adult LV and 4.9 × 1010 in the young LV. In the adult LV the volume per myocyte was 39.5 × 103 µm3 and the number of nuclei per myocyte was 4.2. The numerical density of myocytes was 24.1 × 106 cm?3 and the capillary volume fraction of the adult giraffe ventricle was 0.054. The significantly higher total number of myocyte nuclei in the adult LV, the high density of myocyte nuclei in the LV, and the number of nuclei per myocyte (which was unusually high compared to other mammalian, including human data), all suggest the presence of myocyte proliferation during growth of the animal to increase wall thickness and normalize LV wall tension as the neck lengthens and the need for higher blood pressure ensues. Anat Rec, 296:611–621, 2013. © 2013 Wiley Periodicals, Inc. 相似文献