全文获取类型
收费全文 | 1392篇 |
免费 | 108篇 |
国内免费 | 5篇 |
出版年
2021年 | 24篇 |
2020年 | 21篇 |
2019年 | 17篇 |
2018年 | 36篇 |
2017年 | 33篇 |
2016年 | 45篇 |
2015年 | 65篇 |
2014年 | 69篇 |
2013年 | 98篇 |
2012年 | 99篇 |
2011年 | 91篇 |
2010年 | 57篇 |
2009年 | 40篇 |
2008年 | 56篇 |
2007年 | 54篇 |
2006年 | 46篇 |
2005年 | 48篇 |
2004年 | 30篇 |
2003年 | 30篇 |
2002年 | 33篇 |
2001年 | 29篇 |
2000年 | 31篇 |
1999年 | 19篇 |
1998年 | 19篇 |
1997年 | 9篇 |
1995年 | 10篇 |
1994年 | 15篇 |
1993年 | 12篇 |
1992年 | 16篇 |
1991年 | 24篇 |
1990年 | 16篇 |
1989年 | 14篇 |
1988年 | 19篇 |
1987年 | 30篇 |
1986年 | 21篇 |
1985年 | 26篇 |
1984年 | 17篇 |
1983年 | 12篇 |
1982年 | 15篇 |
1981年 | 9篇 |
1980年 | 10篇 |
1979年 | 13篇 |
1978年 | 9篇 |
1976年 | 8篇 |
1974年 | 9篇 |
1973年 | 14篇 |
1972年 | 8篇 |
1971年 | 8篇 |
1970年 | 10篇 |
1968年 | 8篇 |
排序方式: 共有1505条查询结果,搜索用时 15 毫秒
151.
152.
153.
154.
155.
156.
The aim of the study was to determine the level of infection in mosquitoes with spirochetes Borrelia burgdorferi sensu lato in the woody areas of Szczecin. The mosquitoes were collected from May to September 2003. The spirochetes, Borrelia burgdorferi s. l., present in mosquitoes were detected in mosquitoes with indirect immunofluorescence assay (IFA) using rabbit anti-Borrelia burgdorferi antibodies and goat anti-rabbit IgG marked with fluorescein isocyanate (FITC). A total of 1557 females and 58 males were collected. They represented the genera Aedes (63%) and Culex (37%). The infection level of the mosquitoes from the area studied amounted to 1.7%. The results of the present study confirm the potential of these arthropods to spread Lyme borreliosis. 相似文献
157.
Chiou SH Chen SJ Peng CH Chang YL Ku HH Hsu WM Ho LL Lee CH 《Biochemical and biophysical research communications》2006,343(2):391-400
Fluoxetine is a widely used antidepressant compound which inhibits the reuptake of serotonin in the central nervous system. Recent studies have shown that fluoxetine can promote neurogenesis and improve the survival rate of neurons. However, whether fluoxetine modulates the proliferation or neuroprotection effects of neural stem cells (NSCs) needs to be elucidated. In this study, we demonstrated that 20 microM fluoxetine can increase the cell proliferation of NSCs derived from the hippocampus of adult rats by MTT test. The up-regulated expression of Bcl-2, Bcl-xL and the cellular FLICE-inhibitory protein (c-FLIP) in fluoxetine-treated NSCs was detected by real-time RT-PCR. Our results further showed that fluoxetine protects the lipopolysaccharide-induced apoptosis in NSCs, in part, by activating the expression of c-FLIP. Moreover, c-FLIP induction by fluoxetine requires the activation of the c-FLIP promoter region spanning nucleotides -414 to -133, including CREB and SP1 sites. This effect appeared to involve the phosphatidylinositol-3-kinase-dependent pathway. Furthermore, fluoxetine treatment significantly inhibited the induction of proinflammatory factor IL-1beta, IL-6, and TNF-alpha in the culture medium of LPS-treated NSCs (p<0.01). The results of high performance liquid chromatography coupled to electrochemical detection further confirmed that fluoxentine increased the functional production of serotonin in NSCs. Together, these data demonstrate the specific activation of c-FLIP by fluoxetine and indicate the novel role of fluoxetine for neuroprotection in the treatment of depression. 相似文献
158.
159.
New 2-substituted-phenyl-1H-benzimidazole-5-carboxylic acids (35, 38), ethyl-5-carboxylate (36), -5-carboxamides (37, 39),-5-carboxaldehyde (42), -5-chloro (40), -5-trifluoromethyl (41), and -5-carbonitriles (44-53, 55-67), -6-carbonitrile (54) were prepared and evaluated in vitro against Candida species. The cyano substituted compounds 53, 57, 58 and 61 exhibited the greatest activity with MIC values of 3.12 microg/mL, values similar to that of fluconazole. 相似文献
160.
Deutero-substituted (alpha,alpha,alpha',alpha'-tetradeuterated) derivatives of ifosfamide (IF-d(4)) and its bromo analogue were synthesised. In vitro metabolic studies showed that microsomal hydroxylation of IF-d(4) is slower than for unlabelled compound, suggesting that kinetic isotope effect operates during those transformations. At the same time deutero-substituted derivatives are more active against L1210 leukaemia in mice than unlabelled compounds, suggesting a negative role of side-chain hydroxylation metabolic pathways in the anticancer activity of ifosfamide and its analogues. 相似文献