全文获取类型
收费全文 | 2462篇 |
免费 | 165篇 |
国内免费 | 3篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 64篇 |
妇产科学 | 21篇 |
基础医学 | 443篇 |
口腔科学 | 49篇 |
临床医学 | 195篇 |
内科学 | 531篇 |
皮肤病学 | 49篇 |
神经病学 | 280篇 |
特种医学 | 51篇 |
外科学 | 244篇 |
综合类 | 3篇 |
预防医学 | 193篇 |
眼科学 | 21篇 |
药学 | 197篇 |
中国医学 | 6篇 |
肿瘤学 | 256篇 |
出版年
2024年 | 1篇 |
2023年 | 22篇 |
2022年 | 41篇 |
2021年 | 73篇 |
2020年 | 34篇 |
2019年 | 81篇 |
2018年 | 85篇 |
2017年 | 48篇 |
2016年 | 58篇 |
2015年 | 101篇 |
2014年 | 107篇 |
2013年 | 159篇 |
2012年 | 210篇 |
2011年 | 236篇 |
2010年 | 119篇 |
2009年 | 132篇 |
2008年 | 184篇 |
2007年 | 181篇 |
2006年 | 159篇 |
2005年 | 158篇 |
2004年 | 139篇 |
2003年 | 113篇 |
2002年 | 72篇 |
2001年 | 5篇 |
2000年 | 10篇 |
1999年 | 19篇 |
1998年 | 18篇 |
1997年 | 12篇 |
1996年 | 4篇 |
1995年 | 7篇 |
1994年 | 4篇 |
1993年 | 2篇 |
1992年 | 6篇 |
1990年 | 5篇 |
1988年 | 4篇 |
1987年 | 4篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1981年 | 3篇 |
1977年 | 1篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1972年 | 1篇 |
1971年 | 1篇 |
1969年 | 1篇 |
排序方式: 共有2630条查询结果,搜索用时 156 毫秒
61.
Ribal Al-Aridi Katia El Sibai Pingfu Fu Mehreen Khan Warren R. Selman Baha M. Arafah 《Pituitary》2014,17(6):575-587
Background and objectives
Sellar metastasis is uncommon and poorly characterized as published data include small series of subjects. This study’s goal is to identify unique features that differentiate this entity from other sellar masses such as pituitary macroadenomas.Methods
Published cases of pathologically-confirmed sellar metastasis along with our experience in such patients over a 6-years period were reviewed (total = 129). As a control group, we reviewed similar data on 55 patients with pituitary macroadenomas managed over the same time-period. Presenting symptoms, pituitary dysfunction were analyzed using univariate, multivariate and receiver operating characteristic (ROC) analyses.Results
Sellar metastasis has equal gender distribution with a median patient-age of 56 years. The most common primary malignancy was breast cancer (29 %) in women and lung cancer (30 %) in men. Sellar metastasis was the first manifestation of cancer in over 40 % of patients. Common presenting symptoms included headaches, visual field deficits, abnormal eye motility and diabetes insipidus. These symptoms were less frequent among patients with pituitary macroadenomas. Univariate regression analyses showed that headaches, abnormal eye motility, visual field deficits and diabetes insipidus were each predictive of metastatic disease. ROC analysis combining all 4 features revealed an AUC of 0.953 with a sensitivity of 0.818 and a specificity of 0.935. Using the multivariate regression, abnormal eye motility and/or diabetes insipidus independently predicted metastatic disease.Conclusions
Sellar metastasis should be suspected in patients presenting with sellar masses, abnormal eye motility and/or diabetes insipidus even those without known malignancy since pituitary metastasis can often be the first manifestation of cancer. 相似文献62.
63.
64.
Molecular events underlying interleukin‐6 independence in a subclone of the CMA‐03 multiple myeloma cell line 下载免费PDF全文
Katia Todoerti Laura Mosca Sonia Fabris Marianna D'Anca Elisa Pellegrino Roberto Piva Giorgio Inghirami Chiara Capelli Martino Introna Luca Baldini Raffaella Chiaramonte Luigia Lombardi Antonino Neri 《Genes, chromosomes & cancer》2014,53(2):154-167
We explored the molecular mechanisms involved in the establishement of CMA‐03/06, an IL‐6‐independent variant of the multiple myeloma cell line CMA‐03 previously generated in our Institution. CMA‐03/06 cells grow in the absence of IL‐6 with a doubling time comparable with that of CMA‐03 cells; neither the addition of IL6 (IL‐6) to the culture medium nor co‐culture with multipotent mesenchymal stromal cells increases the proliferation rate, although they maintain the responsiveness to IL‐6 stimulation as demonstrated by STAT1, STAT3, and STAT5 induction. IL‐6 independence of CMA‐03/06 cells is not apparently due to the development of an autocrine IL‐6 loop, nor to the observed moderate constitutive activation of STAT5 and STAT3, since STAT3 silencing does not affect cell viability or proliferation. When compared to the parental cell line, CMA‐03/06 cells showed an activated pattern of the NF‐κB pathway. This finding is supported by gene expression profiling (GEP) analysis identifying an appreciable fraction of modulated genes (28/308) in the CMA‐03/06 subclone reported to be involved in this pathway. Furthermore, although more resistant to apoptotic stimuli compared to the parental cell line, CMA‐03/06 cells display a higher sensibility to NF‐κB inhibition induced by bortezomib. Finally, GEP analysis suggests an involvement of a number of cytokines, which might contribute to IL‐6 independence of CMA‐03/06 by stimulating growth and antiapoptotic processes. In conclusion, the parental cell‐line CMA‐03 and its variant CMA‐03/06 represent a suitable model to further investigate molecular mechanisms involved in the IL‐6‐independent growth of myeloma cells. © 2013 Wiley Periodicals, Inc. 相似文献
65.
Copy number alterations and neoplasia‐specific mutations in MELK,PDCD1LG2, TLN1, and PAX5 at 9p in different neoplasias 下载免费PDF全文
Virinder Kaur Sarhadi Leo Lahti Ilari Scheinin Pekka Ellonen Eeva Kettunen Massimo Serra Katia Scotlandi Piero Picci Sakari Knuutila 《Genes, chromosomes & cancer》2014,53(7):579-588
Genetic alterations affecting 9p are commonly present in many cancer types and many cancer‐related genes are located in this chromosomal region. We sequenced all of the genes located in a 32Mb region of 9p by targeted next generation sequencing (NGS) in 96 patients with different cancer types, including acute lymphoblastic leukemia, bone malignant fibrous histiocytoma/undifferentiated pleomorphic sarcoma, fibrosarcoma, Ewing's sarcoma, and lung carcinoma. Copy number alterations (CNA), and mutations were studied from the NGS data. We detected a deletion at the CDKN2A locus as being the most frequent genetic alteration in all cancer types. In addition to this locus, NGS also identified other small regions of copy number loss and gain. However, different cancer types did not reveal any statistically significant differences with regard to CNA frequency or type. Of the 191 genes within the target region, two novel recurrent mutations were found in the MELK and PDCD1LG2 genes. The most commonly mutated gene in sarcomas was TLN1 (8%) and PAX5 in ALL (9%). Mutations in PAX5, and RUSC2, were seen exclusively in ALL patients and those in KIAA1432, CA9, TLN1, and MELK only in sarcomas (MFH, FS, EFT). Thus using targeted NGS of the 9p region, in addition to commonly deleted CDKN2A locus, we were able to identify a number of small deletions and gains, as well as novel recurrent mutations in different cancer types. © 2014 Wiley Periodicals, Inc. 相似文献
66.
Shim J Perdigou C Chen ER Bertoldi K Reis PM 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(16):5978-5983
We introduce a class of continuum shell structures, the Buckliball, which undergoes a structural transformation induced by buckling under pressure loading. The geometry of the Buckliball comprises a spherical shell patterned with a regular array of circular voids. In order for the pattern transformation to be induced by buckling, the possible number and arrangement of these voids are found to be restricted to five specific configurations. Below a critical internal pressure, the narrow ligaments between the voids buckle, leading to a cooperative buckling cascade of the skeleton of the ball. This ligament buckling leads to closure of the voids and a reduction of the total volume of the shell by up to 54%, while remaining spherical, thereby opening the possibility of encapsulation. We use a combination of precision desktop-scale experiments, finite element simulations, and scaling analyses to explore the underlying mechanics of these foldable structures, finding excellent qualitative and quantitative agreement. Given that this folding mechanism is induced by a mechanical instability, our Buckliball opens the possibility for reversible encapsulation, over a wide range of length scales. 相似文献
67.
Benedikt Bosbach Shayu Deshpande Ferdinand Rossi Jae-Hung Shieh Gunhild Sommer Elisa de Stanchina Darren R. Veach Joseph M. Scandura Katia Manova-Todorova Malcolm A. S. Moore Cristina R. Antonescu Peter Besmer 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(34):E2276
68.
Gazzola V Spezio ML Etzel JA Castelli F Adolphs R Keysers C 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(25):E1657-E1666
Another person's caress is one of the most powerful of all emotional social signals. How much the primary somatosensory cortices (SIs) participate in processing the pleasantness of such social touch remains unclear. Although ample empirical evidence supports the role of the insula in affective processing of touch, here we argue that SI might be more involved in affective processing than previously thought by showing that the response in SI to a sensual caress is modified by the perceived sex of the caresser. In a functional MRI study, we manipulated the perceived affective quality of a caress independently of the sensory properties at the skin: heterosexual males believed they were sensually caressed by either a man or woman, although the caress was in fact invariantly delivered by a female blind to condition type. Independent analyses showed that SI encoded, and was modulated by, the visual sex of the caress, and that this effect is unlikely to originate from the insula. This suggests that current models may underestimate the role played by SI in the affective processing of social touch. 相似文献
69.
Meirelles K Benedict LA Dombkowski D Pepin D Preffer FI Teixeira J Tanwar PS Young RH MacLaughlin DT Donahoe PK Wei X 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(7):2358-2363
Women with late-stage ovarian cancer usually develop chemotherapeutic-resistant recurrence. It has been theorized that a rare cancer stem cell, which is responsible for the growth and maintenance of the tumor, is also resistant to conventional chemotherapeutics. We have isolated from multiple ovarian cancer cell lines an ovarian cancer stem cell-enriched population marked by CD44, CD24, and Epcam (3+) and by negative selection for Ecadherin (Ecad-) that comprises less than 1% of cancer cells and has increased colony formation and shorter tumor-free intervals in vivo after limiting dilution. Surprisingly, these cells are not only resistant to chemotherapeutics such as doxorubicin, but also are stimulated by it, as evidenced by the significantly increased number of colonies in treated 3+Ecad- cells. Similarly, proliferation of the 3+Ecad- cells in monolayer increased with treatment, by either doxorubicin or cisplatin, compared with the unseparated or cancer stem cell-depleted 3-Ecad+ cells. However, these cells are sensitive to Mullerian inhibiting substance (MIS), which decreased colony formation. MIS inhibits ovarian cancer cells by inducing G1 arrest of the 3+Ecad- subpopulation through the induction of cyclin-dependent kinase inhibitors. 3+Ecad- cells selectively expressed LIN28, which colocalized by immunofluorescence with the 3+ cancer stem cell markers in the human ovarian carcinoma cell line, OVCAR-5, and is also highly expressed in transgenic murine models of ovarian cancer and in other human ovarian cancer cell lines. These results suggest that chemotherapeutics may be stimulative to cancer stem cells and that selective inhibition of these cells by treating with MIS or targeting LIN28 should be considered in the development of therapeutics. 相似文献
70.
Arinaminpathy N Ratmann O Koelle K Epstein SL Price GE Viboud C Miller MA Grenfell BT 《Proceedings of the National Academy of Sciences of the United States of America》2012,109(8):3173-3177
Large-scale immunization has profoundly impacted control of many infectious diseases such as measles and smallpox because of the ability of vaccination campaigns to maintain long-term herd immunity and, hence, indirect protection of the unvaccinated. In the case of human influenza, such potential benefits of mass vaccination have so far proved elusive. The central difficulty is a considerable viral capacity for immune escape; new pandemic variants, as well as viral escape mutants in seasonal influenza, compromise the buildup of herd immunity from natural infection or deployment of current vaccines. Consequently, most current influenza vaccination programs focus mainly on protection of specific risk groups, rather than mass prophylactic protection. Here, we use epidemiological models to show that emerging vaccine technologies, aimed at broad-spectrum protection, could qualitatively alter this picture. We demonstrate that sustained immunization with such vaccines could--through potentially lowering transmission rates and improving herd immunity--significantly moderate both influenza pandemic and seasonal epidemics. More subtly, phylodynamic models indicate that widespread cross-protective immunization could slow the antigenic evolution of seasonal influenza; these effects have profound implications for a transition to mass vaccination strategies against human influenza, and for the management of antigenically variable viruses in general. 相似文献