全文获取类型
收费全文 | 438篇 |
免费 | 21篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 6篇 |
2020年 | 3篇 |
2019年 | 6篇 |
2018年 | 12篇 |
2017年 | 8篇 |
2016年 | 19篇 |
2015年 | 23篇 |
2014年 | 26篇 |
2013年 | 42篇 |
2012年 | 45篇 |
2011年 | 44篇 |
2010年 | 21篇 |
2009年 | 18篇 |
2008年 | 23篇 |
2007年 | 26篇 |
2006年 | 21篇 |
2005年 | 18篇 |
2004年 | 17篇 |
2003年 | 13篇 |
2002年 | 19篇 |
2001年 | 6篇 |
2000年 | 4篇 |
1999年 | 4篇 |
1998年 | 1篇 |
1997年 | 7篇 |
1996年 | 1篇 |
1995年 | 1篇 |
1994年 | 1篇 |
1993年 | 5篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 5篇 |
1986年 | 1篇 |
1983年 | 1篇 |
1975年 | 1篇 |
排序方式: 共有459条查询结果,搜索用时 15 毫秒
111.
112.
Biava M Porretta GC Deidda D Pompei R Tafi A Manetti F 《Bioorganic & medicinal chemistry》2004,12(6):1453-1458
We have identified BM212 as a lead compound among a series of pyrrole derivatives with good in vitro activity against mycobacteria and candidae. First studies led us to synthesize some pyrrole compounds in which the thiomorpholine fragment was present. Some compounds revealed very active and these findings prompted us to prepare new pyrrole derivatives 2-15 in the hope of increasing the activity. The microbiological data showed interesting in vitro activity against Mycobacterium tuberculosis and atypical mycobacteria. 相似文献
113.
114.
115.
Lankford SM Macchione M Crews AL McKane SA Akley NJ Martin LD 《In vitro cellular & developmental biology. Animal》2005,41(7):217-224
Summary Mucous cells of the airway epithelium play a crucial role in the pathogenesis of human inflammatory airway diseases. Therefore,
it is of importance to complement in vivo studies that use murine models of allergic asthma with in vitro mechanistic studies
that use murine airway epithelial cells, including mucus-containing cells. In this study, we report the development and characterization
of an in vitro culture system for primary murine tracheal epithelial (MTE) cells comprising ciliated cells and a substantial
number of mucous cells. The increase in mucous cell number over that observed in the native murine airway, or in previously
described murine cultures, creates a culture intermediate between the in vivo murine airway epithelium and in vitro cultures
of human airway epithelial cells. To establish the usefulness of this culture system for the study of epithelial effects during
inflammatory airway diseases, the cells were exposed to interleukin (IL)-13, a central inflammatory mediator in allergic asthma.
The IL-13 induced two characteristic epithelial effects, proliferation and modulation of MUC5AC gene expression. There was
a concentration dependence of these events, wherein high concentrations of IL-13 (10 ng/ml) induced proliferation, whereas
lower concentrations (1 ng/ml) increased MUC5AC mRNA (where mRNA is messenger RNA). Interestingly, these effects occurred
in an inverse manner, with the high concentration of IL-13 also provoking a significant decrease in MUC5AC gene expression.
Thus, MTE cells cultured in this manner may provide an important link between experimental findings from animal models of
allergic asthma and their application to human disease. 相似文献
116.
The potential negative influence of competition from early successional species like blackberry (Rubus fruticosus) may be decisive for the natural regeneration success of drought-sensitive beech (Fagus sylvatica), especially in the light of climate change. With a split plot glasshouse experiment, we investigated the influence of two air temperature and irradiance levels on the competitive interference of blackberry on the water, nitrogen (N) and carbon (C) balance of beech seedlings under moderate drought. When increased temperature was accompanied by low irradiance the biomass, root-to-shoot ratio, N uptake and assimilation rates of blackberry were lower compared with beech, either grown alone or with blackberry. By contrast, when elevated temperature and high irradiance were combined, the root-to-shoot ratio and specific N uptake rate of blackberry were substantially increased, while the N acquisition of beech was impaired. Under lower temperature, with either full light or shade, the presence of blackberry had no significant effects on beech, for almost all tested parameters. Under elevated air temperature beech was impaired by the presence of blackberry at high irradiance. These findings emphasize the interacting effects between environmental factors and competition on the establishment of beech regeneration, which should be considered for future forest management in the frame of climate change. 相似文献
117.
Progesterone enhances ethanol-induced modulation of mesocortical dopamine neurons: antagonism by finasteride 总被引:1,自引:0,他引:1
Dazzi L Serra M Seu E Cherchi G Pisu MG Purdy RH Biggio G 《Journal of neurochemistry》2002,83(5):1103-1109
The effect of endogenous 3α‐hydroxy‐5α‐pregnan‐20‐one (3α,5α‐TH PROG) on the modulation of mesocortical dopamine extracellular concentration by ethanol was investigated by microdialysis in rats. Intraperitoneal injection of progesterone (5 mg/kg, once a day for 5 days) increased the cortical content of 3α,5α‐TH PROG and potentiated the biphasic effect of acute intraperitoneal administration of ethanol on dopamine content. A dose of ethanol (0.25 g/kg) that was ineffective in naïve rats induced a 55% increase in dopamine extracellular concentration in rats pretreated with progesterone. This increase was similar to that induced by a higher dose (0.5 g/kg) of ethanol in naïve rats. Administration of ethanol at 0.5 g/kg to progesterone‐pretreated rats inhibited dopamine content by an extent similar to that observed with an even higher dose (1 g/kg) in naïve rats. The administration of the 5α‐reductase inhibitor finasteride (25 mg/kg, subcutaneous), together with progesterone, prevented the effects of the latter, both on the cortical concentration of 3α,5α‐TH PROG and on the modulation by ethanol of dopamine content. These data suggest that 3α,5α‐TH PROG contributes to the action of ethanol on the mesocortical dopaminergic system. They also suggest that physiological fluctuations in the brain concentrations of neuroactive steroids associated with the oestrous cycle, menopause, pregnancy and stress may alter the response of mesocortical dopaminergic neurons to ethanol. 相似文献
118.
Antonio Ciaramella Francesca Salani Federica Bizzoni Francesco E. Pontieri Alessandro Stefani Mariangela Pierantozzi Francesca Assogna Carlo Caltagirone Gianfranco Spalletta Paola Bossù 《PloS one》2013,8(6)
The role of inflammation in Parkinson’s Disease (PD) is well appreciated, but its underlying mechanisms are still unclear. Our objective was to determine whether dendritic cells (DC), a unique type of migratory immune cells that regulate immunological response and inflammation have an impact on PD. In a case-control study including 80 PD patients and 80 age- and gender-matched healthy control subjects, the two main blood subsets of plasmacytoid and myeloid DC were defined by flow cytometry analysis. Clinical evaluation of subjects consisting of cognition and depression assessment was performed using the Mini Mental State Examination and the Beck Depression Inventory. The severity of motor symptoms was measured using the Unified Parkinson’s Disease Rating Scale-Part III. Comparison between patient and control DC measures and their relationships with clinical assessments were evaluated.The following main results were obtained: 1) the level of circulating DC (mainly the myeloid subset) was significantly reduced in PD patients in comparison with healthy controls; 2) after controlling for depressive and cognitive characteristics, the frequency of myeloid DC was confirmed as one of the independent determinants of PD; 3) the number of both myeloid and plasmacytoid DC was negatively associated with motor symptom severity. Overall, the decline of blood DC, perhaps due to the recruitment of immune cells to the site of disease-specific lesions, can be considered a clue of the immune alteration that characterizes PD, suggesting innovative exploitations of DC monitoring as a clinically significant tool for PD treatment. Indeed, this study suggests that reduced peripheral blood DC are a pathologically-relevant factor of PD and also displays the urgency to better understand DC role in PD for unraveling the immune system contribution to disease progression and thus favoring the development of innovative therapies ideally based on immunomodulation. 相似文献
119.
120.
Renylena Schmidt Renan Rosetti Muniz Elizandra Cola Dulce Stauffert Mariangela Freitas Silveira Angelica E. Miranda 《PloS one》2015,10(10)