全文获取类型
收费全文 | 762篇 |
免费 | 70篇 |
国内免费 | 2篇 |
出版年
2024年 | 1篇 |
2023年 | 4篇 |
2022年 | 10篇 |
2021年 | 26篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 26篇 |
2017年 | 14篇 |
2016年 | 24篇 |
2015年 | 57篇 |
2014年 | 47篇 |
2013年 | 55篇 |
2012年 | 69篇 |
2011年 | 73篇 |
2010年 | 56篇 |
2009年 | 28篇 |
2008年 | 41篇 |
2007年 | 54篇 |
2006年 | 40篇 |
2005年 | 38篇 |
2004年 | 30篇 |
2003年 | 35篇 |
2002年 | 19篇 |
2001年 | 7篇 |
2000年 | 3篇 |
1999年 | 2篇 |
1998年 | 8篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 3篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 4篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 4篇 |
1984年 | 2篇 |
1982年 | 2篇 |
1981年 | 3篇 |
1980年 | 2篇 |
1979年 | 2篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 2篇 |
排序方式: 共有834条查询结果,搜索用时 78 毫秒
831.
Carvalho¹ Carlos E. Menezes Marcelo O. T. Araújo Francisca S. Sfair Júlia C. 《Biodiversity and Conservation》2022,31(4):1217-1228
Biodiversity and Conservation - Protected areas are one of the main strategies of biodiversity conservation. However, if these areas do not coincide spatially with priority areas for conservation,... 相似文献
832.
Extracellular DNase activity was studied in 73 strains of Cryptococcus neoformans and 12 strains of Cryptococcus gattii. DNase activity was measured by DNase agar clearance with and without Methyl Green. All strains tested showed extracellular DNase activity and no significant difference was found betweenC. neoformans and C. gattii strains. DNase production was higher in strains from clinical origin (average radius of 6.2 mm) than among environmental strains (average radius of 2.9 mm). The extracellular enzyme may be detected by DNA substrate PAGE assays and its molecular weight was estimated at 31 kD. These results suggest that extracellular DNase could be considered as a virulence factor involved in C. neoformans–C. gattii species complex pathogenicity. 相似文献
833.
Luis Rodríguez‐Caso Armando Reyes‐Palomares Francisca Sánchez‐Jiménez Ana R. Quesada Miguel Ángel Medina 《Journal of cellular and molecular medicine》2012,16(12):2872-2893
Angiogenesis, the formation of new vessels from pre‐existing ones, is essential during ontogenetic development and is related to many important physio‐pathological processes in the adult. In fact, a persistent and deregulated angiogenesis is a required event for many diseases and pathological situations, including cancer progression and metastasis. Some rare diseases are also angiogenesis‐related pathologies. However, there is a lack of an exhaustive review on the topic. The main purpose of this work is to carry out a systematic review of literature to determine what (and how much) scientific information concerning angiogenesis‐related rare diseases can be extracted from available sources. After exhaustive searches in bibliographic databases, preselected data were filtered by selecting only those articles on rare diseases with an Orpha number hosted in the Orphanet web. The selected bibliographic references were further curated manually. With the 187 selected references, a critical reading and analysis was carried out allowing for an identification and classification of angiogenesis‐related rare diseases, the involved genes and the drugs available for their treatment, all on the basis of the information available in Orphanet database. 相似文献
834.
María S. Almansa Luis A. del Río Carlos F. Alcaraz Francisca Sevilla 《Physiologia plantarum》1989,76(4):563-568
Superoxide dismutases (SOD; EC 1.15.1.1) in leaves from different cultivars of citrus plants were characterized using isoelectric focusing in polyacrylamide gels. The plants studied included Citrus limonum R. (cvs Verna, Fino, and Eureka), C. paradisi Mac (cvs Red Blush and Marsh), C. aurantium L. (cv. Comun), C. sinensis L. Osbeck (cvs Navel, Valencia, and Salustiano), and C. reticulata B. (cv. Satsuma). The three molecular forms of SOD were distinguished from each other by their different sensitivity to cyanide and H2 O2 . In C. limonum leaves, four Cu,Zn-SODs, three Fe-SODs and two Mn-SODs were present. However, in leaves from different varieties of C. sinensis, C. paradisi, C. aurantium and C. reticulata the activity and number of Fe-SOD isoenzymes were lower than in lemon leaves, whereas the number of MN-SOD isozymes was increased. Cu,Zn-SODs did not show significant variations in the different species and cultivars. The identification of Fe-SODs in several species of the plant family Rutaceae extends the small number of higher plants where the presence of these Fe-containing metalloenzymes has been demonstrated. Results obtained may be useful from an evolutionary viewpoint and also in mineral nutrition studies using SOD isozymes as markers of functional metals. 相似文献