全文获取类型
收费全文 | 1153篇 |
免费 | 91篇 |
国内免费 | 1篇 |
出版年
2023年 | 16篇 |
2022年 | 19篇 |
2021年 | 59篇 |
2020年 | 39篇 |
2019年 | 52篇 |
2018年 | 52篇 |
2017年 | 58篇 |
2016年 | 59篇 |
2015年 | 93篇 |
2014年 | 104篇 |
2013年 | 102篇 |
2012年 | 107篇 |
2011年 | 98篇 |
2010年 | 63篇 |
2009年 | 50篇 |
2008年 | 56篇 |
2007年 | 49篇 |
2006年 | 27篇 |
2005年 | 35篇 |
2004年 | 31篇 |
2003年 | 24篇 |
2002年 | 15篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 6篇 |
1997年 | 1篇 |
1996年 | 1篇 |
1995年 | 4篇 |
1994年 | 1篇 |
1990年 | 2篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 1篇 |
1983年 | 1篇 |
1981年 | 1篇 |
1977年 | 1篇 |
1974年 | 1篇 |
排序方式: 共有1245条查询结果,搜索用时 15 毫秒
991.
Maria Victoria Rosato-Siri Leandro Marziali María Eugenia Guitart Maria Elvira Badaracco Mariana Puntel Fernando Pitossi Jorge Correale Juana Maria Pasquini 《Molecular neurobiology》2018,55(2):1068-1081
When disrupted, iron homeostasis negatively impacts oligodendrocyte (OLG) differentiation and impairs myelination. To better understand myelin formation and OLG maturation, in vivo and in vitro studies were conducted to evaluate the effect of iron deficiency (ID) not only on OLG maturation but also on astrocytes (AST) and microglial cells (MG). In vivo experiments in an ID model were carried out to describe maturational events during OLG and AST development and the reactive profile of MG during myelination when iron availability is lower than normal. In turn, in vitro assays were conducted to explore proliferating and maturational states of each glial cell type derived from control or ID conditions. Studies targeted NG2, PDGFRα, CNPAse, CC1, and MBP expression in OLG, GFAP and S100 expression in AST, and CD11b, ED1, and cytokine expression in MG, as well as BrDU incorporation in the three cell types. Our results show that ID affected OLG development at early stages, not only reducing their maturation capacity but also increasing their proliferation and affecting their morphological complexity. AST ID proliferated more than control ones and were more immature, much like OLG. Cytokine expression in ID animals reflected an anti-inflammatory state which probably influenced OLG maturation. These results show that ID conditions alter all glial cells and may impact myelin formation, which could be regulated by a mechanism involving a cross talk between AST, MG, and oligodendrocyte progenitors (OPC). 相似文献
992.
Botton Vanderleia Piovan Leandro Meier Henry França Mitchell David Alexander Cordova Jesús Krieger Nadia 《Bioprocess and biosystems engineering》2018,41(4):573-583
Bioprocess and Biosystems Engineering - A fermented solid containing lipases was produced by solid-state fermentation of Rhizopus microsporus on sugarcane bagasse enriched with urea, soybean oil,... 相似文献
993.
994.
Lorenzelli L Margesin B Martinoia S Tedesco MT Valle M 《Biosensors & bioelectronics》2003,18(5-6):621-626
In the last decade, fundamental advances in whole cell based sensors and microsystems have established the extracellular acidification rate monitoring of cell cultures as an important indicator of the global cellular metabolism. Innovative approaches adopting advanced integrated sensor array-based microsystems represent an emerging technique with numerous biomedical applications. This paper reports a cell-based microsystem, for multisite monitoring of the physiological state of cell populations. The functional components of the microsystem are an ion sensitive field effect transistor (ISFET) array-based sensor chip and a CMOS integrated circuit for signal conditioning and sensor signal multiplexing. In order to validate the microsystem capabilities for in-vitro toxicity screening applications, preliminary experimental measurements with Cheratinocytes, and CHO cells are presented. Variations in the acidification rate, imputable to the inhibitory effect of the drug on the metabolic cell activity have been monitored and cell viability during long term measurements has been also demonstrated. 相似文献
995.
The chondrocranium and cranial muscles of Lysapsus limellum, Pseudis cardosoi, P. minuta and four subspecies of P. paradoxa (caribensis, occidentalis, paradoxa and platensis) are described. Lysapsus and Pseudis are related to the Hylidae by: (1) vertical processus anterolateralis of the larval crista parotica, and (2) presence of m. mandibulolabialis inferior and superior (the latter reversed in P. cardosoi). We confirm some larval synapomorphies previously proposed for the pseudids, except the m. subarcualis obliquus II having one head and the absence of copula anterior. We add three new features for the pseudids: (1) the distal end of ceratobranchiales III and IV projects towards either the capsula auditiva (Lysapsus) or the processus basicapsularis – new term – (Pseudis); (2) the arcus subocularis is twice as wide at the level of the processus ascendens as it is just posterior to the processus muscularis quadrati, and (3) the lateral corner of the processus articularis quadrati largely projects laterally. We diagnose Lysapsus larvae (the states of Pseudis in parentheses) as follows: (1) short processus pseudopterygoideus (long), (2) absence of lateral development of larval crista parotica (presence), (3) absence of commissura proximalis II (presence), (4) presence of processus lateralis hyalis – new term – (absence), (5) absence of processus basicapsularis (presence), (6) processus ascendens slightly curved along its entire extent (curved at the union with the basi cranii only), and (7) absence of m. tympanopharyngeus (presence). 相似文献
996.
Mariana Malzoni Furtado Erika Midori Kida Hayashi Susan Dora Allendorf Claudio José Coelho Anah Tereza de Almeida Jácomo Jane Megid José Domingues Ramos Filho Leandro Silveira Natália Mundim Tôrres José Soares Ferreira Neto 《EcoHealth》2016,13(3):549-557
Human population growth around protected areas increases the contact between wild and domestic animals, promoting disease transmission between them. This study investigates the exposure of free-ranging wild carnivores and domestic dogs to canine distemper virus (CDV) and parvovirus in Emas National Park (ENP) in the Cerrado savanna of central Brazil. Serum samples were collected from 169 wild carnivores, including the maned wolf (Chrysocyon brachyurus), crab-eating fox (Cerdocyon thous), hoary fox (Pseudalopex vetulus), puma (Puma concolor), ocelot (Leopardus pardalis), pampas cat (Leopardus colocolo), jaguarundi (Herpailurus yagouaroundi), striped hog-nosed skunk (Conepatus semistriatus) and coati (Nasua nasua), and from 35 domestic dogs living on rural properties bordering ENP. Serological tests showed that 10.6% of wild carnivores (maned wolves, crab-eating foxes and ocelots) and 71.4% of domestic dogs were exposed to CDV, and 56.8% of wild carnivores, including all species sampled except coatis, and 57.1% of domestic dogs were exposed to parvovirus. This report is the first to indicate that the free-ranging pampas cat, jaguarundi and striped hog-nosed skunk are exposed to parvovirus. CDV and parvovirus deserve attention in ENP, and it is extremely important to monitor the health of carnivore populations and perform molecular diagnosis of the viruses to determine the possible involvement of the domestic dog in their transmission. 相似文献
997.
Planta - Elicitation of E. grandis plants with Streptomyces PM9 reduced the gray-mold disease, through increasing the levels of enzymes directly related to the induction of plant defense responses,... 相似文献
998.
999.