全文获取类型
收费全文 | 1479篇 |
免费 | 148篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 13篇 |
儿科学 | 35篇 |
妇产科学 | 7篇 |
基础医学 | 241篇 |
口腔科学 | 32篇 |
临床医学 | 206篇 |
内科学 | 285篇 |
皮肤病学 | 21篇 |
神经病学 | 133篇 |
特种医学 | 73篇 |
外科学 | 219篇 |
综合类 | 7篇 |
一般理论 | 2篇 |
预防医学 | 73篇 |
眼科学 | 16篇 |
药学 | 152篇 |
中国医学 | 2篇 |
肿瘤学 | 116篇 |
出版年
2024年 | 5篇 |
2023年 | 12篇 |
2022年 | 19篇 |
2021年 | 59篇 |
2020年 | 26篇 |
2019年 | 65篇 |
2018年 | 65篇 |
2017年 | 33篇 |
2016年 | 49篇 |
2015年 | 42篇 |
2014年 | 68篇 |
2013年 | 91篇 |
2012年 | 107篇 |
2011年 | 96篇 |
2010年 | 73篇 |
2009年 | 49篇 |
2008年 | 90篇 |
2007年 | 90篇 |
2006年 | 84篇 |
2005年 | 72篇 |
2004年 | 85篇 |
2003年 | 72篇 |
2002年 | 67篇 |
2001年 | 4篇 |
2000年 | 7篇 |
1999年 | 21篇 |
1998年 | 12篇 |
1997年 | 6篇 |
1995年 | 4篇 |
1994年 | 3篇 |
1993年 | 6篇 |
1992年 | 7篇 |
1991年 | 11篇 |
1990年 | 19篇 |
1989年 | 11篇 |
1988年 | 13篇 |
1987年 | 13篇 |
1986年 | 8篇 |
1985年 | 5篇 |
1984年 | 5篇 |
1983年 | 3篇 |
1982年 | 3篇 |
1981年 | 6篇 |
1980年 | 6篇 |
1979年 | 6篇 |
1974年 | 3篇 |
1973年 | 3篇 |
1970年 | 3篇 |
1968年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有1633条查询结果,搜索用时 19 毫秒
31.
Milind Singh Brindar Sandhu Aaron Scurto Cory Berkland Michael S. Detamore 《Acta biomaterialia》2010,6(1):137-143
Shape-specific, macroporous tissue engineering scaffolds were fabricated and homogeneously seeded with cells in a single step. This method brings together CO2 polymer processing and microparticle-based scaffolds in a manner that allows each to solve the key limitation of the other. Specifically, microparticle-based scaffolds have suffered from the limitation that conventional microsphere sintering methods (e.g., heat, solvents) are not cytocompatible, yet we have shown that cell viability was sustained with subcritical (i.e., gaseous) CO2 sintering of microspheres in the presence of cells at near-ambient temperatures. On the other hand, the fused microspheres provided the pore interconnectivity that has eluded supercritical CO2 foaming approaches. Here, fused poly(lactide-co-glycolide) microsphere scaffolds were seeded with human umbilical cord mesenchymal stromal cells to demonstrate the feasibility of utilizing these matrices for cartilage regeneration. We also demonstrated that the approach may be modified to produce thin cell-loaded patches as a promising alternative for skin tissue engineering applications. 相似文献
32.
In this review, reports from last year on the following topics are summarized: (1) reviews of bronchiolitis in infants; respiratory syncytial virus (RSV)-associated illness, including possible viral mechanisms of alteration of airway function and results of an epidemiologic study of bronchiolitis-associated mortality. Studies evaluating (2) the use of serum eosinophilic cationic protein as a marker for development of subsequent persistent wheezing infants; (3) parental bronchial responsiveness as an indicator of genetic susceptibility to acute bronchiolitis; (4) prophylactic use of monoclonal antibody (Palivizumab) to control an outbreak of RSV in a hospital nursery; (5) a controlled clinical trial of ribaviron in acutely ill children; (6) reports of new associations with bronchiolitis obliterans organizing pneumonia (BOOP); (7) case reports of use of methotrexate as an alternate to corticosteroids in treatment of BOOP; (8) a newly described entity, eosinophilic bronchiolitis. 相似文献
33.
Blumer JB Lord K Saunders TL Pacchioni A Black C Lazartigues E Varner KJ Gettys TW Lanier SM 《Endocrinology》2008,149(8):3842-3849
Activator of G protein signaling (AGS)-3 plays functional roles in cell division, synaptic plasticity, addictive behavior, and neuronal development. As part of a broad effort to define the extent of functional diversity of AGS3-regulated-events in vivo, we generated AGS3 null mice. Surprisingly, AGS3 null adult mice exhibited unexpected alterations in cardiovascular and metabolic functions without any obvious changes in motor skills, basic behavioral traits, and brain morphology. AGS3 null mice exhibited a lean phenotype, reduced fat mass, and increased nocturnal energy expenditure. AGS3 null mice also exhibited altered blood pressure control mechanisms. These studies expand the functional repertoire for AGS3 and other G protein regulatory proteins providing unexpected mechanisms by which G protein systems may be targeted to influence obesity and cardiovascular function. 相似文献
34.
Stem cell factor induces eosinophil activation and degranulation: mediator release and gene array analysis 总被引:22,自引:1,他引:22 下载免费PDF全文
Eosinophils are effector cells that play an important role in the damage induced by the allergic process by releasing inflammatory mediators and proteolytic factors after activation. Stem cell factor (SCF) is a primary cytokine involved in hematopoiesis and mast cell differentiation, proliferation, and activation. Studies have also indicated that SCF is directly involved in pathogenesis of allergic airway inflammation. In the present study, we examined the ability of SCF to activate murine eosinophils for increased mediator release and up-regulation of chemokines. Initial data demonstrated that eosinophils have significant levels of surface c-kit protein, SCF receptor. SCF-activated eosinophils degranulate and release eosinophil peroxidase and leukotriene C(4) in a dose-dependent manner. In addition, SCF was further shown to induce the release of CC chemokines, RANTES, macrophage-derived chemokine (MDC), macrophage inflammatory protein-1beta (MIP-1beta), and C10 from eosinophils. To identify the extent of SCF-induced activation of eosinophils, we also performed gene array analysis using an array containing 1153 genes related to inflammation, including cytokines and their receptors, growth factors, structural and cytoskeletal genes, signal transduction genes as well as several other classes related to immune/inflammatory responses. The gene analysis indicated that more than 150 genes were significantly up-regulated in eosinophils after SCF stimulation. The gene array results were verified using a quantitative real-time polymerase chain reaction analysis to identify the expression of several chemokine and chemokine receptor genes. Altogether, these studies indicate that SCF is a potent eosinophil degranulator and activator that may play a number of roles during an inflammatory/immune response. 相似文献
35.
36.
Joo-Yong Jung Ranjna Madan-Lala Maria Georgieva Jyothi Rengarajan Charles D. Sohaskey Franz-Christoph Bange Cory M. Robinson 《Infection and immunity》2013,81(9):3198-3209
Nitric oxide (NO) is a diffusible radical gas produced from the activity of nitric oxide synthase (NOS). NOS activity in murine macrophages has a protective role against mycobacteria through generation of reactive nitrogen intermediates (RNIs). However, the production of NO by human macrophages has remained unclear due to the lack of sensitive reagents to detect NO directly. The purpose of this study was to investigate NO production and the consequence to mycobacteria in primary human macrophages. We found that Mycobacterium bovis BCG or Mycobacterium tuberculosis infection of human macrophages induced expression of NOS2 and NOS3 that resulted in detectable production of NO. Treatment with gamma interferon (IFN-γ), l-arginine, and tetrahydrobiopterin enhanced expression of NOS2 and NOS3 isoforms, as well as NO production. Both of these enzymes were shown to contribute to NO production. The maximal level of NO produced by human macrophages was not bactericidal or bacteriostatic to M. tuberculosis or BCG. The number of viable mycobacteria was increased in macrophages that produced NO, and this requires expression of nitrate reductase. An narG mutant of M. tuberculosis persisted but was unable to grow in human macrophages. Taken together, these data (i) enhance our understanding of primary human macrophage potential to produce NO, (ii) demonstrate that the level of RNIs produced in response to IFN-γ in vitro is not sufficient to limit intracellular mycobacterial growth, and (iii) suggest that mycobacteria may use RNIs to enhance their survival in human macrophages. 相似文献
37.
Fumitake Saito Toshihiro Ito Judith M. Connett Matthew A. Schaller William F. Carson IV Cory M. Hogaboam Rosemary Rochford Steven L. Kunkel 《Inflammation》2013,36(6):1295-1303
Murine gammaherpesvirus 68 (MHV68) is a natural rodent pathogen that has been used as a model to study the pathogenesis of human gammaherpesviruses. Like other herpesviruses, MHV68 causes acute infection and establishes life-long latency in the host. Recently, it has been shown that mice latently infected with MHV68 have resistance to unrelated pathogens in secondary infection models. We therefore hypothesized that latent MHV68 infection could modulate the host response to influenza A virus. To test this hypothesis, mice were infected intranasally with influenza virus following the establishment of MHV68 latency. Mice latently infected with MHV68 showed significantly higher survival to influenza A virus infection than did PBS mock-infected mice. Latent MHV68 infection led to lower influenza viral loads and decreased inflammatory pathology in the lungs. Alveolar macrophages of mice latently infected with MHV68 showed activated status, and adoptive transfer of those activated macrophages into mice followed the infection with influenza A virus had significantly greater survival rates than control mice, suggesting that activated alveolar macrophages are a key mechanistic component in protection from secondary infections. 相似文献
38.
39.
40.
Madigan Cory G. Adams Michael B. Chu Chu-Chiao Dinkha Laith R. Farrell Samuel J. Hoard Robert T. Keithler Andrea N. Loudermilk Kevin A. Rouse Jessica Walker Brandon L. Williams Susan G. Wyatt Andrew C. Gore Rosco S. Thomas Dustin M. 《The international journal of cardiovascular imaging》2021,37(12):3583-3588
The International Journal of Cardiovascular Imaging - To compare overall number of downstream tests and total costs between negative exercise stress echocardiograms (ESE) or cardiac computed... 相似文献