全文获取类型
收费全文 | 689篇 |
免费 | 58篇 |
国内免费 | 61篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 22篇 |
妇产科学 | 4篇 |
基础医学 | 58篇 |
口腔科学 | 7篇 |
临床医学 | 75篇 |
内科学 | 388篇 |
皮肤病学 | 9篇 |
神经病学 | 10篇 |
特种医学 | 88篇 |
外科学 | 30篇 |
综合类 | 27篇 |
预防医学 | 15篇 |
眼科学 | 6篇 |
药学 | 47篇 |
中国医学 | 1篇 |
肿瘤学 | 20篇 |
出版年
2022年 | 2篇 |
2021年 | 22篇 |
2020年 | 10篇 |
2019年 | 18篇 |
2018年 | 16篇 |
2017年 | 14篇 |
2016年 | 14篇 |
2015年 | 17篇 |
2014年 | 16篇 |
2013年 | 15篇 |
2012年 | 13篇 |
2011年 | 17篇 |
2010年 | 20篇 |
2009年 | 24篇 |
2008年 | 13篇 |
2007年 | 60篇 |
2006年 | 31篇 |
2005年 | 41篇 |
2004年 | 33篇 |
2003年 | 33篇 |
2002年 | 21篇 |
2001年 | 17篇 |
2000年 | 18篇 |
1999年 | 21篇 |
1998年 | 31篇 |
1997年 | 39篇 |
1996年 | 27篇 |
1995年 | 27篇 |
1994年 | 15篇 |
1993年 | 26篇 |
1992年 | 4篇 |
1991年 | 14篇 |
1990年 | 10篇 |
1989年 | 23篇 |
1988年 | 13篇 |
1987年 | 12篇 |
1986年 | 6篇 |
1985年 | 4篇 |
1984年 | 8篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 12篇 |
1979年 | 2篇 |
1978年 | 2篇 |
1976年 | 3篇 |
1975年 | 3篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1903年 | 1篇 |
排序方式: 共有808条查询结果,搜索用时 15 毫秒
31.
Mice are a widely utilized in vivo model for translational salivary gland research but must be used with caution. Specifically, mouse salivary glands are similar in many ways to human salivary glands (i.e., in terms of their anatomy, histology, and physiology) and are both readily available and relatively easy and affordable to maintain. However, there are some significant differences between the two organisms, and by extension, the salivary glands derived from them must be taken into account for translational studies. The current review details pertinent similarities and differences between human and mouse salivary glands and offers practical guidelines for using both for research purposes. 相似文献
32.
计算机程序化的初均速法测定双黄连注射液的稳定性 总被引:2,自引:0,他引:2
用计算机程序化的初均速法,测定了双黄连溶液中3种主要成分——绿原酸、黄苓甙、连翘甙的活化能及室温贮存期。该方法简便、快速、结果准确。对临床应用有一定价值。 相似文献
33.
CL Martyn-Simmons L Green G Ash RW Groves CH Smith JNWN Barker 《Journal of the European Academy of Dermatology and Venereology》2009,23(12):1394-1397
Background Targeted biologic therapies have made a significant impact on the treatment for moderate to severe psoriasis. In the United Kingdom, the National Institute for Health and Clinical Excellence recommends etanercept, a human recombinant tumour necrosis factor (TNF) receptor fusion protein, for moderate to severe psoriasis patients who have failed conventional therapies. There is, however, no data available on the role of other TNF antagonists for patients who have failed etanercept. Adalimumab, a fully human, anti-TNF monoclonal antibody, is approved for treatment of moderate to severe psoriasis.
Objectives To assess the efficacy and safety of adalimumab (40 mg weekly) in psoriasis patients who were non-responders to high-dosage etanercept (50 mg twice weekly).
Methods All patients attending a tertiary referral service for severe psoriasis who were non-responders to high-dosage etanercept [i.e. failed to achieve ≥ 50% improvement in Psoriasis Area and Severity Index (PASI 50) after 12 weeks of treatment] were considered for open-label adalimumab therapy for 12 weeks. Details on clinical course, PASI, Dermatology Life Quality Index (DLQI) and adverse events were recorded at baseline and weeks 2, 4, 8, and 12.
Results Four of five patients in this study had reached at least PASI 50 by week 12. Of these, two patients achieved a 75% improvement in PASI (PASI 75). No serious adverse events were reported.
Conclusions Initial data from this open-label prospective evaluation suggests that weekly adalimumab therapy is an effective treatment for patients with severe psoriasis who had failed to respond to at least 3 months of high-dosage etanercept. 相似文献
Objectives To assess the efficacy and safety of adalimumab (40 mg weekly) in psoriasis patients who were non-responders to high-dosage etanercept (50 mg twice weekly).
Methods All patients attending a tertiary referral service for severe psoriasis who were non-responders to high-dosage etanercept [i.e. failed to achieve ≥ 50% improvement in Psoriasis Area and Severity Index (PASI 50) after 12 weeks of treatment] were considered for open-label adalimumab therapy for 12 weeks. Details on clinical course, PASI, Dermatology Life Quality Index (DLQI) and adverse events were recorded at baseline and weeks 2, 4, 8, and 12.
Results Four of five patients in this study had reached at least PASI 50 by week 12. Of these, two patients achieved a 75% improvement in PASI (PASI 75). No serious adverse events were reported.
Conclusions Initial data from this open-label prospective evaluation suggests that weekly adalimumab therapy is an effective treatment for patients with severe psoriasis who had failed to respond to at least 3 months of high-dosage etanercept. 相似文献
34.
35.
36.
37.
Murine hematopoietic stem and progenitor cells: I. Enrichment and biologic characterization 总被引:2,自引:5,他引:2
Murine bone marrow cells were fractionated by fluorescence-activated cell sorting into Rh123lo Lin- c-kit+ Ly6A+, Rh123hi Lin-c-kit+ Ly6A+, and Lin- c-kit+ Ly6A- populations within which most, if not all, of the hematopoietic activities of the marrow resided. The Rh123lo Lin- c- kit+Ly6A+ cells, which consist exclusively of small- or medium-sized lymphocyte-like cells, are highly enriched for long-term hematopoietic in vivo repopulating cells. The enrichment factor for these cells from the marrow was estimated as 2,000-fold. The Rh123hi Lin- c-kit+ Ly6A+ cells, although also highly enriched for day-12 spleen colony-forming units, were relatively depleted of long-term in vivo repopulation capacity. Most, if not all Lin- c-kit+ Ly6A- cells were Rb123hi. In contrast to both Rh123lo and Rh123hi Lin- c-kit+ Ly6A+ stem cell populations, the Lin- c-kit+ Ly6A- cells can be stimulated to proliferate in vitro in the presence of single cytokines, which is a characteristic of committed progenitor cells. No marked synergistic interactions between individual cytokines were observed with this cell population. Both Rh123hi Lin- c-kit+ Ly6A+ mature stem cell and Lin- c- kit+ Ly6A- progenitor cell populations displayed in vivo repopulation kinetics resembling those of the putative short-term hematopoietic repopulating cells. 相似文献
38.
To determine the relationship between equilibrium binding of thrombin to sites on the platelet surface and the cleavage of membrane glycoprotein V (GPV) by thrombin, we examined the effect of active site- modified thrombin (1-chloro-3-tosylamido-7-amino-L-2-heptanone thrombin toslysCH2-thrombin) on the binding of native thrombin to platelets and on the hydrolysis of GPV by native thrombin. ToslysCH2-thrombin inhibited binding of native thrombin to high affinity sites on the platelet surface. In contrast, hydrolysis of GPV by native thrombin, even at threshold thrombin concentrations, was not inhibited by pretreatment with toslysCH2-thrombin at concentrations up to 210 nmol/L. ToslysCH2-thrombin also had no appreciable effect on platelet aggregation or release of 14C-serotonin induced by native thrombin. Because toslysCH2-thrombin does not inhibit platelet release, aggregation, or GPV hydrolysis by native thrombin but does inhibit high affinity surface binding by native thrombin, these results indicate that thrombin binding and hydrolysis of GPV are separate and unrelated events. 相似文献
39.
Wang LM Zhang Q Zhu W He C Lu CL Ding DF Chen ZY 《第二军医大学学报》2005,26(11):1299-1299
Glial cell line-derived neurotrophic factor (GDNF) plays a critical role in neurodevelopment and survival of midbrain dopaminergic and spinal motor neurons in vitro and in vivo. The biological actions of GDNF are mediated by a two-receptor complex consisting of a glycosylphosphatidylinositol-linked cell surface molecule, the GDNF family receptor alpha 1 (GFR alpha 1), and receptor protein tyrosine kinase Ret. Although structural analysis of GDNF has been extensively examined, less is known about the structural basis of GFR alpha 1 function. In this study, based on evolutionary trace method and relative solvent accessibility prediction of residues, a set of trace residues that are solvent-accessible was selected for site-directed mutagenesis. A series of GFR alpha 1 mutations was made, and PC12 cell lines stably expressing different GFR alpha 1 mutants were generated. According to the survival and differentiation responses of these stable PC12 cells upon GDNF stimulation and the GDNF- GFR alpha 1-Ret interaction assay, residues 152NN153, Arg259, and 316SNS318 in the GFR alpha 1 central region were found to be critical for GFR alpha 1 binding to GDNF and eliciting downstream signal transduction. The single mutation R259A in the GFR alpha 1 molecule simultaneously lost its binding ability to GDNF and Ret. However N152A/N153A or S316A/N317A/ S318A mutation in the GFR alpha 1 molecule still retained the ability to bind with Ret. These findings suggest that distinct structural elements in GFR alpha 1 may be involved in binding to GDNF and Ret. 相似文献
40.