全文获取类型
收费全文 | 239篇 |
免费 | 11篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 14篇 |
妇产科学 | 4篇 |
基础医学 | 43篇 |
口腔科学 | 8篇 |
临床医学 | 19篇 |
内科学 | 44篇 |
皮肤病学 | 1篇 |
神经病学 | 6篇 |
特种医学 | 47篇 |
外科学 | 10篇 |
预防医学 | 30篇 |
眼科学 | 1篇 |
药学 | 11篇 |
中国医学 | 1篇 |
肿瘤学 | 8篇 |
出版年
2021年 | 3篇 |
2020年 | 2篇 |
2019年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 7篇 |
2015年 | 2篇 |
2014年 | 5篇 |
2013年 | 5篇 |
2012年 | 7篇 |
2011年 | 4篇 |
2010年 | 11篇 |
2009年 | 11篇 |
2008年 | 6篇 |
2007年 | 7篇 |
2006年 | 8篇 |
2005年 | 8篇 |
2004年 | 7篇 |
2003年 | 6篇 |
2002年 | 4篇 |
2001年 | 5篇 |
2000年 | 3篇 |
1999年 | 4篇 |
1998年 | 12篇 |
1997年 | 15篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1994年 | 8篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 3篇 |
1990年 | 1篇 |
1989年 | 9篇 |
1988年 | 7篇 |
1987年 | 12篇 |
1986年 | 6篇 |
1985年 | 12篇 |
1984年 | 2篇 |
1983年 | 4篇 |
1982年 | 2篇 |
1981年 | 1篇 |
1980年 | 4篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1975年 | 6篇 |
1973年 | 1篇 |
1966年 | 1篇 |
排序方式: 共有250条查询结果,搜索用时 15 毫秒
241.
Background
Although a grossly disproportionate burden of disease from HIV/AIDS, TB and malaria remains in the Global South, these infectious diseases have finally risen to the top of the international agenda in recent years. Ideal strategies for combating these diseases must balance the advantages and disadvantages of 'vertical' disease control programs and 'horizontal' capacity-building approaches. 相似文献242.
Mutations of factor VIII cleavage sites in hemophilia A 总被引:10,自引:1,他引:9
Hemophilia A is caused by a defect in coagulation factor VIII, a protein that undergoes extensive proteolysis during its activation and inactivation. To determine whether some cases of hemophilia are caused by mutations in important cleavage sites, we screened patient DNA samples for mutations in these sites by a two-step process. Regions of interest were amplified from genomic DNA by repeated rounds of primer- directed DNA synthesis. The amplified DNAs were then screened for mutations by discriminant hybridization using oligonucleotide probes. Two cleavage site mutations were found in a survey of 215 patients. A nonsense mutation in the activated protein C cleavage site at amino acid 336 was discovered in a patient with severe hemophilia. In another severely affected patient, a mis-sense mutation results in a substitution of cysteine for arginine in the thrombin activation site at amino acid 1689. This defect is associated with no detectable factor VIII activity, but with normal levels of factor VIII antigen. The severe hemophilia in this patient was sporadic; analysis of the mother suggested that the mutation originated in her gametes or during her embryogenesis. The results demonstrate that this approach can be used to identify factor VIII gene mutations in regions of the molecule known to be important for function. 相似文献
243.
244.
Magnetic resonance (MR) imaging of the patient with acute cervical injury is important because of the potential prognostic significance of the appearance of the spinal cord at the time of injury. However, cervical traction may involve equipment incompatible with the magnetic environment, and transferring the patient to the imaging table may make it difficult to maintain traction. The authors describe a simple, inexpensive, and reliable method for providing cervical traction within the magnet room. 相似文献
245.
Background
There is little experience with carefully developed interventions in the HIV/STI prevention field aimed at adult heterosexual target groups in the Netherlands. The ability to apply intervention development protocols, like Intervention Mapping, in daily practice outside of academia, is a matter of concern. An urgent need also exists for interventions aimed at the prevention of STI in migrant populations in the Netherlands. This article describes the theory and evidence based development of HIV/STI prevention interventions by the Municipal Public Health Service Rotterdam Area (MPHS), the Netherlands, for heterosexual migrant men with Surinamese, Dutch-Caribbean, Cape Verdean, Turkish and Moroccan backgrounds. 相似文献246.
A combination of poloxamers increases gene expression of plasmid DNA in skeletal muscle 总被引:2,自引:0,他引:2
Lemieux P Guérin N Paradis G Proulx R Chistyakova L Kabanov A Alakhov V 《Gene therapy》2000,7(11):986-991
Intramuscular administration of plasmid DNA is a promising strategy to express therapeutic genes, however, it is limited by a relatively low level of gene expression. We report here that a non-ionic carrier, SP1017, composed of two amphiphilic block copolymers, pluronics L61 and F127, also known as poloxamers, significantly increases intramuscular expression of plasmid DNA. Two reporter genes, luciferase and beta-galactosidase, and one therapeutic gene, erythropoietin, were injected intramuscularly with and without SP1017 into C57Bl/6 and Balb/C mice and Sprague-Dawley rats. SP1017 increased gene expression by about 10-fold and maintained higher gene expression compared with naked DNA. Comparison of SP1017 with polyvinyl pyrrolidone (PVP) showed that SP1017 exhibited a significantly higher efficacy and its optimal dose was 500-fold lower. Experiments with beta-galactosidase using X-gal staining suggested that SP1017 considerably increased plasmid DNA diffusion through the tissue. SP1017 also improved expression of the erythropoietin gene leading to an increase in its systemic level and hematocrits. Previous toxicity studies have suggested that SP1017 has over a 1000-fold safety margin. Poloxamers used in SP1017 are listed in the US Pharmacopeia as inactive excipients and are widely used in a variety of clinical applications. We believe that the described system constitutes a simple and efficient gene transfer method to achieve local or systemic production of therapeutic proteins. 相似文献
247.
248.
249.
Andrzej B Pop?awski Micha? Jankowski Stephen W Erickson Teresita D��az de St?hl E Christopher Partridge Chiquito Crasto Jingyu Guo John Gibson Uwe Menzel Carl EG Bruder Aneta Kaczmarczyk Magdalena Benetkiewicz Robin Andersson Johanna Sandgren Barbara Zegarska Dariusz Ba?a Ewa ?rutek David B Allison Arkadiusz Piotrowski Wojciech Zegarski Jan P Dumanski 《European journal of human genetics : EJHG》2010,18(5):560-568
250.