全文获取类型
收费全文 | 149562篇 |
免费 | 5289篇 |
国内免费 | 923篇 |
专业分类
155774篇 |
出版年
2023年 | 203篇 |
2022年 | 601篇 |
2021年 | 1036篇 |
2020年 | 587篇 |
2019年 | 765篇 |
2018年 | 12665篇 |
2017年 | 11290篇 |
2016年 | 8866篇 |
2015年 | 3231篇 |
2014年 | 3212篇 |
2013年 | 3728篇 |
2012年 | 8535篇 |
2011年 | 16696篇 |
2010年 | 14371篇 |
2009年 | 10349篇 |
2008年 | 12977篇 |
2007年 | 14255篇 |
2006年 | 3163篇 |
2005年 | 3128篇 |
2004年 | 3514篇 |
2003年 | 3296篇 |
2002年 | 2741篇 |
2001年 | 1976篇 |
2000年 | 1779篇 |
1999年 | 1309篇 |
1998年 | 569篇 |
1997年 | 531篇 |
1996年 | 452篇 |
1995年 | 421篇 |
1994年 | 343篇 |
1993年 | 360篇 |
1992年 | 726篇 |
1991年 | 632篇 |
1990年 | 545篇 |
1989年 | 551篇 |
1988年 | 469篇 |
1987年 | 461篇 |
1986年 | 359篇 |
1985年 | 369篇 |
1984年 | 316篇 |
1983年 | 286篇 |
1982年 | 233篇 |
1981年 | 199篇 |
1979年 | 274篇 |
1978年 | 245篇 |
1977年 | 228篇 |
1976年 | 196篇 |
1974年 | 244篇 |
1972年 | 445篇 |
1971年 | 420篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
92.
Siddhartha Kumar Bhaumik Manoj Kumar Singh Subir Karmakar Tripti De 《Glycoconjugate journal》2009,26(6):663-673
As compared to cutaneous leishmaniasis, vaccination against visceral leishmaniasis (VL) has received limited attention. In
this study, we demonstrate for the first time that an UDP-Galactose: N-acetylglucosamine β 1–4 galactosyltransferase (GenBank Accession No. EF159943) expressing attenuated LD clonal population (A-LD) is able to confer protection against the experimental challenge with the virulent LD AG83 parasite. A-LD was also effective in established leishmania infection. The vaccinated animals showed both cell mediated
(in vitro T-cell proliferation, and DTH response) and humoral responses (Th1 type). These results demonstrate the potential of the
attenuated clones as an immunotherapeutic and immunoprophylactic agent against visceral leishmaniasis. 相似文献
93.
Hyperthermic treatment at 43 degrees C suppressed the growth of Ehrlich ascites tumor (EAT) cells in vitro. Incubation of EAT cells at 43 degrees C for as little as 1.5 h totally abolished the transplantability of the tumor. At the same time, the rate of cellular glucose uptake, the density of glucose transporter on the cells as well as the extent of thymidine, uridine and leucine incorporation were significantly reduced. 相似文献
94.
95.
96.
97.
Effect of membrane additives on vesicle fusion 总被引:1,自引:0,他引:1
A large variety of alkyl derivatives were found to either slow or block the low-temperature induced fusion of dipalmitoylphosphatidylcholine small unilamellar vesicles (DPPC SUV) when incorporated into the SUV bilayer at five mol%. Only corn oil was fusogenic. 相似文献
98.
Shallow-water vegetated estuarine habitats, notably seagrass, mangrove and saltmarsh, are known to be important habitats for
many species of small or juvenile fish in temperate Australia. However, the movement of fish between these habitats is poorly
understood, and yet critical to the management of the estuarine fisheries resource. We installed a series of buoyant pop nets
in adjacent stands of seagrass, mangrove and saltmarsh in order to determine how relative abundance of fishes varied through
lunar cycles. Nets were released in all habitats at the peak of the monthly spring tide for 12 months, and in the seagrass
habitat at the peak of the neap tide also. The assemblage of fish in each habitat differed during the spring tides. The seagrass
assemblage differed between spring and neap tide, with the neap tide assemblage showing greater abundances of fish, particularly
those species which visited the adjacent habitats when inundated during spring tides. The result supports the hypothesis that
fish move from the seagrass to the adjacent mangrove and saltmarsh during spring tides, taking advantage of high abundances
of zooplankton, and use seagrass as a refuge during lower tides. The restoration and preservation of mangrove and saltmarsh
utility as fish habitat may in some situations be linked to the proximity of available seagrass. 相似文献
99.
100.