全文获取类型
收费全文 | 3507篇 |
免费 | 257篇 |
国内免费 | 17篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 69篇 |
妇产科学 | 41篇 |
基础医学 | 644篇 |
口腔科学 | 24篇 |
临床医学 | 406篇 |
内科学 | 868篇 |
皮肤病学 | 91篇 |
神经病学 | 283篇 |
特种医学 | 40篇 |
外科学 | 426篇 |
综合类 | 4篇 |
一般理论 | 1篇 |
预防医学 | 257篇 |
眼科学 | 50篇 |
药学 | 251篇 |
中国医学 | 1篇 |
肿瘤学 | 312篇 |
出版年
2023年 | 28篇 |
2022年 | 52篇 |
2021年 | 114篇 |
2020年 | 59篇 |
2019年 | 87篇 |
2018年 | 114篇 |
2017年 | 68篇 |
2016年 | 96篇 |
2015年 | 104篇 |
2014年 | 131篇 |
2013年 | 177篇 |
2012年 | 278篇 |
2011年 | 313篇 |
2010年 | 160篇 |
2009年 | 152篇 |
2008年 | 255篇 |
2007年 | 244篇 |
2006年 | 243篇 |
2005年 | 249篇 |
2004年 | 222篇 |
2003年 | 177篇 |
2002年 | 171篇 |
2001年 | 22篇 |
2000年 | 14篇 |
1999年 | 15篇 |
1998年 | 23篇 |
1997年 | 20篇 |
1996年 | 10篇 |
1995年 | 18篇 |
1994年 | 6篇 |
1993年 | 4篇 |
1992年 | 8篇 |
1991年 | 7篇 |
1990年 | 9篇 |
1988年 | 7篇 |
1987年 | 7篇 |
1986年 | 5篇 |
1984年 | 6篇 |
1982年 | 5篇 |
1979年 | 6篇 |
1978年 | 5篇 |
1975年 | 4篇 |
1974年 | 11篇 |
1973年 | 6篇 |
1972年 | 17篇 |
1971年 | 9篇 |
1970年 | 6篇 |
1969年 | 4篇 |
1968年 | 7篇 |
1967年 | 8篇 |
排序方式: 共有3781条查询结果,搜索用时 188 毫秒
51.
52.
Hours S Nunes H Kambouchner M Uzunhan Y Brauner MW Valeyre D Brillet PY 《Medicine》2008,87(3):142-151
Pulmonary cavitary lesions in the absence of concomitant comorbidities are an uncommon and often confusing manifestation of sarcoidosis. We retrospectively reviewed the clinical and high-resolution computed tomography (HRCT) characteristics and the natural history of a series of 23 patients with pulmonary cavitary lesions found on HRCT extracted from a large cohort of patients with pulmonary sarcoidosis. The estimated prevalence of cavitary sarcoidosis was 2.2%. Cavitary lesions developed in patients with severe and active sarcoidosis (serum angiotensin-converting enzyme [SACE] > or =2 times the upper limit of normal range: 63.6%). Twelve (52.2%) patients had evidence of radiographic stage IV, 9 of whom (75%) had persistently increased SACE. As found on HRCT, cavitary lesions were multiple in 21 patients (91.3%), including 5 patients with 10 or more cavities. The size of cavitary lesions was variable, with a median diameter of 20 mm (range, 11-100 mm). Follow-up was available for 20 patients with a median follow-up of 6.25 years (range, 6 months to 15 years). Seven patients (35%) experienced some type of complication related to cavitary lesions, including 6 episodes of hemoptysis in 5 patients and aspergilloma occurrence in 3 patients. As seen on HRCT, the evolution of the number and size of cavitary lesions was variable, with a complete resolution of the largest cavitary lesion in only 5 patients (25%). During follow-up, wall thickening was always associated with a further infectious complication. In summary, cavitary lesions are rare in pulmonary sarcoidosis and usually occur in active and severe sarcoidosis. Their evolution is unpredictable, and complications are frequent. 相似文献
53.
Emilie Mamessier Joo Y. Song Franziska C. Eberle Svetlana Pack Charlotte Drevet Bruno Chetaille Ziedulla Abdullaev José Adela?de Daniel Birnbaum Max Chaffanet Stefania Pittaluga Sandrine Roulland Andreas Chott Elaine S. Jaffe Bertrand Nadel 《Haematologica》2014,99(3):481-488
The pathogenesis of follicular lymphoma is a multi-hit process progressing over many years through the accumulation of numerous genetic alterations. Besides the hallmark t(14;18), it is still unclear which other oncogenic hits contribute to the early steps of transformation and in which precursor stages these occur. To address this issue, we performed high-resolution comparative genomic hybridization microarrays on laser-capture micro-dissected cases of follicular lymphoma in situ (n=4), partial involvement by follicular lymphoma (n=4), and duodenal follicular lymphoma (n=4), assumed to represent, potentially, the earliest stages in the evolution of follicular lymphoma. Cases of reactive follicular hyperplasia (n=2), uninvolved areas from follicular lymphoma in situ lymph nodes, follicular lymphoma grade 1–2 (n=5) and follicular lymphoma grade 3A (n=5) were used as controls. Surprisingly, alterations involving several relevant (onco)genes were found in all entities, but at significantly lower proportions than in overt follicular lymphoma. While the number of alterations clearly assigns all these entities as precursors, the pattern of partial involvement by follicular lymphoma alterations was quantitatively and qualitatively closer to that of follicular lymphoma, indicating significant selective pressure in line with its faster rate of progression. Among the most notable alterations, we observed and validated deletions of 1p36 and gains of the 7p and 12q chromosomes and related oncogenes, which include some of the most recurrent oncogenic alterations in overt follicular lymphoma (TNFRSF14, EZH2, MLL2). By further delineating distinctive and hierarchical molecular and genetic features of early follicular lymphoma entities, our analysis underlines the importance of applying appropriate criteria for the differential diagnosis. It also provides a first set of candidates likely to be involved in the cascade of hits that pave the path of the various progression phases to follicular lymphoma development. 相似文献
54.
Jérôme Boursier Victor de Ledinghen Nathalie Sturm Laïla Amrani Yannick Bacq Jérémy Sandrini Brigitte Le Bail Julien Chaigneau Jean-Pierre Zarski Yves Gallois Vincent Leroy Zaytouna Al Hamany Frédéric Oberti Isabelle Fouchard-Hubert Nina Dib Sandrine Bertrais Marie-Christine Rousselet Paul Calès 《Journal of gastroenterology》2014,49(3):527-537
Background
Liver stiffness evaluation (LSE) by Fibroscan is now widely used to assess liver fibrosis in chronic hepatitis C. Liver steatosis is a common lesion in chronic hepatitis C as in other chronic liver diseases, but its influence on LSE remains unclear. We aimed to precisely determine the influence of steatosis on LSE by using quantitative and precise morphometric measurements of liver histology.Methods
650 patients with chronic hepatitis C, liver biopsy, and LSE were included. Liver specimens were evaluated by optical analysis (Metavir F and A, steatosis grading) and by computerized morphometry to determine the area (%, reflecting quantity) and fractal dimension (FD, reflecting architecture) of liver fibrosis and steatosis.Results
The relationships between LSE and liver histology were better described using morphometry. LSE median was independently linked to fibrosis (area or FD), steatosis (area or FD), activity (serum AST), and IQR/LSE median. Steatosis area ≥4.0 % induced a 50 % increase in LSE result in patients with fibrosis area <9 %. In patients with IQR/LSE median ≤0.30, the rate of F0/1 patients misclassified as F ≥ 2 by Fibroscan was, respectively for steatosis area <4.0 and ≥4.0 %: 12.6 vs 32.4 % (p = 0.003). Steatosis level did not influence LSE median when fibrosis area was ≥9 %, and consequently did not increase the rate of F ≤ 3 patients misclassified as cirrhotic.Conclusion
A precise evaluation of liver histology by computerized morphometry shows that liver stiffness measured by Fibroscan is linked to liver fibrosis, activity, and also steatosis. High level of steatosis induces misevaluation of liver fibrosis by Fibroscan. 相似文献55.
Séverine Bouttefroy Sandrine Meunier Vanessa Milien Mohamed Boucekine Pierre Chamouni Dominique Desprez Annie Harroche Audrey Hochart Marie Françoise Thiercelin-Legrand Bénédicte Wibaut Hervé Chambost Lucia Rugeri the CoDeC study group 《British journal of haematology》2020,188(2):317-320
This FranceCoag network study assessed 33 patients with congenital factor XIII (FXIII) deficiency presenting FXIII levels <10 iu/dl. Diagnosis was based on abnormal bleeding in 29 patients, a positive family history in 2, recurrent miscarriages in 1 and was fortuitous in 1. Eighteen patients (62·1%) presented life-threatening umbilical or intracranial haemorrhages (ICH). Seven of the 15 patients who experienced ICH were diagnosed but untreated, including 3 with secondary neurological sequelae. All pregnancies without prophylaxis (26/26) led to miscarriages versus 3/16 with prophylaxis. In patients exhibiting FXIII levels <10 iu/dl, prophylaxis could be discussed at diagnosis and at pregnancy. Further controlled prospective studies are needed. 相似文献
56.
Silne Parisse Jean‐Fabien Petit Alexandre Forzy Alexandre Lecardeur Sandrine Beaugrand Pascal Palmas 《Macromolecular chemistry and physics.》2020,221(2)
1H NMR spin diffusion is shown to advantageously complement scanning electron microscopy (SEM) observations for the characterization of polymer structuring in composite materials. It is here demonstrated on a material containing a few percent of polymer binder and a crystalline organic/inorganic mixture as reinforcement. In SEM observations, polymer accumulations are seen. However, the polymer is also expected to fill small porosities and thin layers at the interface of particles to ensure the cohesion and the mechanical properties of the assembly. In most cases, this polymer structuring is invisible considering the resolution and contrast achieved by SEM on such material. It is thus investigated taking advantage of the two‐step decay of nuclear magnetic resonance spin diffusion curves. Average thickness values of 30 and 188 nm are estimated for the interphase and the overall polymer, respectively. Such structural information improves the knowledge of structure/property relationships and provides better understanding of material properties and making processes. 相似文献
57.
58.
Jean‐Philippe Galanaud Marc Righini Lorris Le Collen Aymeric Douillard Helia Robert‐Ebadi Daniel Pontal David Morrison Marie‐Thrse Barrellier Antoine Diard Herv Gunnguez Dominique Brisot Pascale Faïsse Sandrine Accassat Myriam Martin Aurlien Delluc Susan Solymoss Jeannine Kassis Marc Carrier Isabelle Qur Susan R. Kahn 《Journal of thrombosis and haemostasis》2020,18(4):857-864
59.