全文获取类型
收费全文 | 8890篇 |
免费 | 565篇 |
国内免费 | 58篇 |
专业分类
耳鼻咽喉 | 52篇 |
儿科学 | 223篇 |
妇产科学 | 257篇 |
基础医学 | 1384篇 |
口腔科学 | 190篇 |
临床医学 | 777篇 |
内科学 | 1869篇 |
皮肤病学 | 84篇 |
神经病学 | 822篇 |
特种医学 | 354篇 |
外国民族医学 | 1篇 |
外科学 | 1300篇 |
综合类 | 86篇 |
一般理论 | 12篇 |
预防医学 | 734篇 |
眼科学 | 178篇 |
药学 | 580篇 |
中国医学 | 4篇 |
肿瘤学 | 606篇 |
出版年
2023年 | 52篇 |
2022年 | 90篇 |
2021年 | 167篇 |
2020年 | 84篇 |
2019年 | 160篇 |
2018年 | 214篇 |
2017年 | 130篇 |
2016年 | 155篇 |
2015年 | 199篇 |
2014年 | 292篇 |
2013年 | 389篇 |
2012年 | 493篇 |
2011年 | 547篇 |
2010年 | 306篇 |
2009年 | 264篇 |
2008年 | 504篇 |
2007年 | 533篇 |
2006年 | 485篇 |
2005年 | 441篇 |
2004年 | 501篇 |
2003年 | 447篇 |
2002年 | 411篇 |
2001年 | 139篇 |
2000年 | 154篇 |
1999年 | 168篇 |
1998年 | 104篇 |
1997年 | 70篇 |
1996年 | 72篇 |
1995年 | 74篇 |
1994年 | 61篇 |
1993年 | 46篇 |
1992年 | 85篇 |
1991年 | 57篇 |
1990年 | 62篇 |
1989年 | 54篇 |
1988年 | 62篇 |
1987年 | 56篇 |
1986年 | 71篇 |
1985年 | 57篇 |
1984年 | 66篇 |
1983年 | 57篇 |
1982年 | 45篇 |
1981年 | 46篇 |
1980年 | 43篇 |
1979年 | 37篇 |
1978年 | 43篇 |
1977年 | 42篇 |
1975年 | 33篇 |
1974年 | 28篇 |
1973年 | 39篇 |
排序方式: 共有9513条查询结果,搜索用时 15 毫秒
151.
152.
153.
154.
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
155.
156.
157.
Anat Brunstein Klomek Israel Orbach Leo Sher Eliane Sommerfeld Robyne Diller Alan Apter 《Archives of Suicide Research》2013,17(2):133-140
This study examined the relationship between suicidality and dependent and self-critical depression among adolescents. Ninety-six adolescents participated: 32 suicidal inpatients, 32 nonsuicidal inpatients and 32 healthy controls. The groups were matched for gender, age and education. Participants completed the Depressive Experience Questionnaire for Adolescents (DEQ-A), the Cognition Checklist (CCL), and the Multi-Attitude Suicidal Tendencies Scale (MAST). Results indicated that suicidal adolescents have significantly higher levels of self-critical and dependent depression, compared to nonsuicidal inpatients and healthy controls. The distinctive quality of depression among suicidal adolescents suggests assessment and treatment strategies for these individuals. 相似文献
158.
Abstract The case described is a serious parasuicide (failed suicide) by voluntary ingestion of a considerable amount of highly poisonous mushrooms (Amanita phalloides). The liver transplant performed straight afterwards enabled the patient to survive, but after a period of relative well-being in the immediate postoperative period, her pervasive suicidal ideation returned to the fore in all its dramatic ambivalence. The difficulties involved in managing the case and the decision to transplant a living organ in an individual who has just attempted suicide are discussed. 相似文献
159.
Jia Luo Emi Ashikaga Philip P. Rubin Michaela J. Heimann Keri L. Hildick Paul Bishop Fatima Girach Fernando Josa-Prado Leo T. H. Tang Ruth E. Carmichael Jeremy M. Henley Kevin A. Wilkinson 《Neuromolecular medicine》2013,15(4):692-706
Timely and efficient information transfer at synapses is fundamental to brain function. Synapses are highly dynamic structures that exhibit long-lasting activity-dependent alterations to their structure and transmission efficiency, a phenomenon termed synaptic plasticity. These changes, which occur through alterations in presynaptic release or in the trafficking of postsynaptic receptor proteins, underpin the formation and stabilisation of neural circuits during brain development, and encode, process and store information essential for learning, memory and cognition. In recent years, it has emerged that the ubiquitin-like posttranslational modification SUMOylation is an important mediator of several aspects of neuronal and synaptic function. Through orchestrating synapse formation, presynaptic release and the trafficking of postsynaptic receptor proteins during forms of synaptic plasticity such as long-term potentiation, long-term depression and homeostatic scaling, SUMOylation is being increasingly appreciated to play a central role in neurotransmission. In this review, we outline key discoveries in this relatively new field, provide an update on recent progress regarding the targets and consequences of protein SUMOylation in synaptic function and plasticity, and highlight key outstanding questions regarding the roles of protein SUMOylation in the brain. 相似文献
160.
Rasche L Bernard C Topp MS Kapp M Duell J Wesemeier C Haralambieva E Maeder U Einsele H Knop S 《Annals of hematology》2012,91(7):1031-1037
Extramedullary (e) relapse in multiple myeloma(MM) has an adverse prognosis, but knowledge concerning biological features and preferred treatment is scarce. We screened the myeloma registry of our institution for eMM relapses and identified 24 cases among 357 patients (pts).Only 8% of eMM relapses occurred after initial therapy, but 54% occurred after third-line or subsequent therapy. Baseline molecular cytogenetics revealed high-risk features in 10 of 19 evaluable patients. Most frequently, eMM presented as soft tissue (67%) and organ involvement (25%) or malignant effusion (12.5%). Incidence of leptomeningeal/CNS involvement was 21%. At eMM relapse, bone marrow infiltration was absent in 46% and low in 21%. Ten eMM biopsies were available showing increased proliferation, i.e., Ki-67 of 67%(range, 30–90%) of all cancer cells. Pts received radiation therapy, dose-intense chemotherapy, novel agents, and allogeneic SCT resulting in an overall response rate of 54%. Median progression-free survival was 2 (95% CI 0.08–3.92) and median overall survival 7 months (95% CI 3.56–10.43), respectively,with only three patients being alive at 12 months from diagnosis. EMM relapse may present at any anatomical site with frequent CNS involvement. Biological features include increased proliferation and low rate of marrow involvement.Prognosis remains poor despite intensive treatment. 相似文献