全文获取类型
收费全文 | 748篇 |
免费 | 50篇 |
国内免费 | 9篇 |
出版年
2023年 | 3篇 |
2022年 | 16篇 |
2021年 | 29篇 |
2020年 | 13篇 |
2019年 | 15篇 |
2018年 | 26篇 |
2017年 | 29篇 |
2016年 | 26篇 |
2015年 | 55篇 |
2014年 | 30篇 |
2013年 | 46篇 |
2012年 | 50篇 |
2011年 | 73篇 |
2010年 | 47篇 |
2009年 | 35篇 |
2008年 | 36篇 |
2007年 | 35篇 |
2006年 | 42篇 |
2005年 | 23篇 |
2004年 | 18篇 |
2003年 | 18篇 |
2002年 | 13篇 |
2001年 | 19篇 |
2000年 | 9篇 |
1999年 | 15篇 |
1998年 | 10篇 |
1997年 | 11篇 |
1996年 | 7篇 |
1995年 | 4篇 |
1994年 | 7篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1987年 | 4篇 |
1986年 | 5篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1978年 | 2篇 |
1977年 | 2篇 |
1972年 | 1篇 |
1966年 | 2篇 |
1965年 | 3篇 |
1961年 | 1篇 |
1960年 | 2篇 |
1959年 | 1篇 |
1957年 | 3篇 |
1955年 | 1篇 |
1954年 | 2篇 |
1951年 | 1篇 |
排序方式: 共有807条查询结果,搜索用时 15 毫秒
121.
Bacterial and Arachnid Sphingomyelinases D: Comparison of Biophysical and Pathological Activities
下载免费PDF全文
![点击此处可从《Journal of cellular biochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
122.
Targeted unlabeled multiple reaction monitoring analysis of cell markers for the study of sample heterogeneity in isolated rat brain cortical microvessels
下载免费PDF全文
![点击此处可从《Journal of neurochemistry》网站下载免费的PDF全文](/ch/ext_images/free.gif)
David Gomez‐Zepeda Catarina Chaves Méryam Taghi Philippe Sergent Wang‐Qing Liu Cérina Chhuon Michel Vidal Martin Picard Elizabeth Thioulouse Isabelle Broutin Ida‐Chiara Guerrera Jean‐Michel Scherrmann Yannick Parmentier Xavier Decleves Marie‐Claude Menet 《Journal of neurochemistry》2017,142(4):597-609
123.
Flávia Rosa Santoro Gilney Charll Santos Washington Soares Ferreira Júnior Leonardo da Silva Chaves Thiago Antonio Sousa Araújo Andre Luiz Borba Nascimento André Sobral Josivan Soares Silva Juliana Loureiro Almeida Campos Ulysses Paulino Albuquerque 《Evolutionary biology》2017,44(2):216-226
The malaria hypothesis, which addresses a strong selective pressure on human genes resulting from a chain of processes that originated with the practice of agriculture, is an example of an evolutionary consequence of niche construction. This scenario has led us to formulate the following questions: Are the genetic adaptations of populations with a history of contact with malaria reflected in the local medical systems? Likewise, could environmental changes (deforestation) and the incidence of malaria result in an adaptive response in these local health care systems? We collected secondary data for the entire African continent from different databases and secondary sources and measured the response of health care systems as the variation in the richness of antimalarial medicinal plants. Our results did not indicate a cause-and-effect relationship between the tested variables and the medical systems, but a subsequent analysis of variance showed an increase in the mean of medicinal plants in regions with a higher incidence of malaria prior to disease control measures. We suggest that this response had a greater impact on local medical knowledge than other variables, such as genetic frequency and deforestation. 相似文献
124.
Ellen Moreno da Silva Marianne Rodrigues Fernandes Darlen Cardoso de Carvalho Luciana Pereira Colares Leitao Giovanna Chaves Cavalcante Esdras Edgar Batista Pereira Antônio André Conde Modesto João Farias Guerreiro Paulo Pimentel de Assumpção Sidney Emanuel Batista dos Santos Ney Pereira Carneiro dos Santos 《BMC research notes》2017,10(1):761
125.
Reference values for TSH may be inadequate to define hypothyroidism in persons with morbid obesity: Di@bet.es study
下载免费PDF全文
![点击此处可从《Obesity (Silver Spring, Md.)》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Sergio Valdés Cristina Maldonado‐Araque Ana Lago‐Sampedro Juan Antonio Lillo‐Muñoz Eduardo Garcia‐Fuentes Vidal Perez‐Valero Carolina Gutiérrez‐Repiso Eva Garcia‐Escobar Albert Goday Inés Urrutia Laura Peláez Alfonso Calle‐Pascual Elena Bordiú Luis Castaño Conxa Castell Elias Delgado Edelmiro Menéndez Josep Franch‐Nadal Sonia Gaztambide Joan Girbés Emilio Ortega Joan Vendrell Matilde R. Chacón F. Javier Chaves Federico Soriguer Gemma Rojo‐Martínez 《Obesity (Silver Spring, Md.)》2017,25(4):788-793
126.
M. Amélia Santos Marco Gil Lurdes Gano Sílvia Chaves 《Journal of biological inorganic chemistry》2005,10(5):564-580
A series of extra-functionalized 3-hydroxy-4-pyridinone chelators of hard metal ions, containing different side-chains with peptidomimetic groups, was studied to assess the effect of those groups on the physico-chemical properties, the metal-chelating affinity and the in vivo behaviour of the compounds, in view of their potential pharmaceutical applications. Besides the synthesis of the chelators, the study of their properties in aqueous solution alone and in the presence of M
3+ (M = Fe, Ga and Al) was performed by potentiometric/spectroscopic techniques. The octanol/water partition coefficient values of these hydroxypyridinone derivatives cover ca. 3 orders of magnitude (1.1 > log P > −2). They all form very stable tris-chelated M(III) complexes, the pFe and pGa values ranging up to five orders of magnitude. The in vivo studies showed the effect of the ligands on the biodistribution of 67Ga citrate and also of 67Ga-complexes in mice, in view of the potential use of the ligands or complexes as metal decorporating or as imaging agents, respectively. Although almost all these peptidomimetic hydroxypyridinone derivatives present very rapid clearance rate from most organs, the L-ornithine derivative (H2L9) shows to be superior to the others and as good as Deferiprone as metal decontaminant of Ga. Concerning the 67Ga complexes, the benzyl-propylamine (H2L3) shows considerable bone retention, thus suggesting its potential application as imaging agent.Electronic Supplementary Material Supplementary material is available for this article at
An erratum to this article can be found at 相似文献
127.
Kerly Wollmeister Hofmann Artur Francisco Schumacher Schuh Jonas Saute Raquel Townsend Daniele Fricke Renata Leke Diogo O. Souza Luis Valmor Portela Márcia Lorena Fagundes Chaves Carlos R. M. Rieder 《Neurochemical research》2009,34(8):1401-1404
Several lines of evidence suggest that neuroimmune mechanisms may be involved in the neurodegenerative process of Parkinson’s
disease (PD). Interleukin-6 (IL-6) is increased in the nigrostriatal region and in the cerebrospinal fluid of patients with
PD. IL-6 serum level was evaluated in PD patients. The effects of levodopa treatment and disease severity on IL-6 were also
studied. The IL-6 levels were similar between PD patients (treated and not treated) and controls. However, there was a negative
correlation of IL-6 levels and the activities of daily living scale (P < 0.05), indicating that patients with more severe disease have higher levels of this cytokine. No correlation involving
levodopa treatment and IL-6 serum level was found. The results suggest that only marginal effects of IL-6 occur on the peripheral
immune system, and that the role of IL-6 and others neuroimmune factors needs to be well elucidated on PD. 相似文献
128.
东亚飞蝗hunchback基因在卵子形成和胚胎发育过程中的原位表达 总被引:1,自引:0,他引:1
hb(hunchback)基因是昆虫胚胎前后轴模式形成的关键基因.对东亚飞蝗(Locusta migratoria manilensis,Meyen)hb基因的功能已有报道,但其表达模式还不清楚.为了研究胁基因在东亚飞蝗卵子形成和胚胎发育过程中的时空表达情况,本研究采用免疫组化方法在蛋白质水平上检测了hb基因的时空表达模式.在卵子形成过程中,hb基因局限在卵细胞核区中表达,随着卵子的发育逐渐移至卵细胞的后端;卵受精后,核区里的Hb蛋白向外扩散,在卵后端形成浓度梯度;胚盘期,hb基因在胚盘中央呈带状表达;胚盘分化为原头和原躯干后,表达条带变宽,并呈现出梯度表达,该表达区域将形成颌、胸部的部分体节;随着腹节开始形成,hb基因在颌胸部的表达逐渐减弱,而在腹部后端的“生长区”表达,并呈现出不连续性.经比较,hb易基因在昆虫颌胸部的表达较为保守,而在卵子形成过程中和腹部的表达具有较大的变异性.与黑腹果蝇等长胚带昆虫相比,东亚飞蝗hb基因在体节形成的基因级联调控中具有更重要、更直接的调控作用. 相似文献
129.
目的建立心脏特异表达LMNAE82K转基因小鼠,为研究LMNAE82K与心肌病发病机制的关系提供工具动物。方法把LMNAE82K基因插入α-MHC启动子下游,构建转基因表达载体,显微注射法建立C57BL/6JLMNAE82K转基因小鼠,PCR鉴定转基因小鼠的基因型,采用Western Blot鉴定LMNAE82K在心脏组织中的表达,H&E染色和超声检测转基因小鼠心脏的病理改变。结果建立了2个心脏组织特异表达LMNAE82K的转基因小鼠品系。超声检查显示转基因小鼠心室壁变薄,收缩期容积和舒张期容积增加,射血分数及短轴缩短率降低。结论LMNAE82K转基因小鼠具有LMNAE82K引起的家族性扩心病有类似的病理变化,为研究LMNAE82K与心肌病发病机制的关系的研究提供了有价值的疾病动物模型。 相似文献
130.
Suzana Passos Chaves Eduardo Caio Torres-Santos Camila Marques Vanessa Ribeiro Figliuolo Pedro Muanis Persechini Robson Coutinho-Silva Bartira Rossi-Bergmann 《Microbes and infection / Institut Pasteur》2009,11(10-11):842-849
The purinergic P2X7 receptor is a membrane protein of leucocytes involved in the clearance of intracellular bacteria such as Chlamydia and Mycobacterium. In this work, we investigated the role and modulation of macrophage P2X7R in intracellular infection with the protozoan parasite Leishmania amazonensis. Upon infection, isolated murine macrophages displayed enhanced expression of P2X7R and were significantly more responsive to extracellular ATP (ATPe)-induced pore opening, as demonstrated by the increased uptake of Lucifer Yellow. This was extended to the in vivo situation, where cells from established cutaneous lesions were more sensitive to ATPe than cells from uninfected mice. ATP treatment of infected macrophages inhibited parasite growth, and this was prevented by pre-treatment with oxidized ATP, a selective antagonist of P2X7R. Parasite killing was unlikely due to induction of nitric oxide production or cytolysis of infected macrophage, as those functions were unaltered with parasite-effective ATPe concentrations. A direct drug effect is also unlike, as ATPe enhanced axenic parasite growth. We found that leishmanial infection rendered wild-type but not P2X7R-deficient macrophages more prone to ATP-induced apoptosis. These results show that macrophage infection with L. amazonensis leads to enhanced expression of functional P2X7R, that upon ligation with ATPe helps in the elimination of the parasites by an as yet unclear mechanism possibly involving host cell apoptosis. 相似文献