全文获取类型
收费全文 | 237篇 |
免费 | 12篇 |
国内免费 | 1篇 |
出版年
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 5篇 |
2013年 | 10篇 |
2012年 | 13篇 |
2011年 | 4篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 8篇 |
2007年 | 5篇 |
2006年 | 9篇 |
2005年 | 6篇 |
2004年 | 4篇 |
2003年 | 8篇 |
2002年 | 6篇 |
2001年 | 6篇 |
2000年 | 6篇 |
1999年 | 8篇 |
1998年 | 4篇 |
1996年 | 3篇 |
1990年 | 3篇 |
1985年 | 5篇 |
1984年 | 4篇 |
1982年 | 3篇 |
1980年 | 4篇 |
1979年 | 4篇 |
1978年 | 3篇 |
1976年 | 6篇 |
1974年 | 3篇 |
1968年 | 2篇 |
1966年 | 2篇 |
1952年 | 2篇 |
1950年 | 2篇 |
1942年 | 2篇 |
1941年 | 2篇 |
1938年 | 2篇 |
1936年 | 4篇 |
1935年 | 2篇 |
1934年 | 3篇 |
1933年 | 4篇 |
1932年 | 4篇 |
1931年 | 2篇 |
1929年 | 2篇 |
1928年 | 2篇 |
1925年 | 4篇 |
1924年 | 2篇 |
1923年 | 4篇 |
1922年 | 3篇 |
1921年 | 3篇 |
1920年 | 5篇 |
排序方式: 共有250条查询结果,搜索用时 15 毫秒
1.
2.
3.
Yeast cells are incapable of translating RNAs containing the poliovirus 5'' untranslated region: evidence for a translational inhibitor. 下载免费PDF全文
We have expressed in the yeast Saccharomyces cerevisiae a full-length poliovirus cDNA clone under the control of the GAL10 promoter to better characterize the effect of poliovirus on host cell metabolism. We find that yeast cells are unable to translate poliovirus RNA in vivo and that this inhibition is mediated through the 5' untranslated region of the viral RNA. The in vivo inhibition of translation of poliovirus RNA and P2CAT RNA (which contains the 5' untranslated region fused upstream of the bacterial chloramphenicol transferase gene) can be mimicked in vitro in yeast translation lysates. In fact, a trans-acting inhibitor present in yeast lysates can inhibit translation of either poliovirus or P2CAT RNA in HeLa cell translation lysates. In contrast, when the inhibitor is added to translations programmed with chloramphenicol acetyltransferase RNA, yeast prepro-alpha-factor RNA, or an RNA containing the internal ribosome entry site of encephalomyocarditis virus, no inhibition is seen. The inhibitory activity has been partially purified by DEAE-Sephacel chromatography. The partially purified inhibitor is heat stable, escapes phenol extraction, is resistant to proteinase K and DNase I treatment, and is sensitive to RNase A digestion, suggesting that the inhibitor is an RNA. In an in vitro translation assay, the inhibitory activity can be overcome by increasing the concentration of HeLa cell lysate but not P2CAT RNA, suggesting that the inhibitor interacts (directly or indirectly) with one or more components of the HeLa cell translational machinery rather than with the viral RNA. 相似文献
4.
5.
6.
7.
Katy Morgan Roach Stephen Mark Duffy William Coward Carol Feghali-Bostwick Heike Wulff Peter Bradding 《PloS one》2013,8(12)
Background
Idiopathic pulmonary fibrosis (IPF) is a common, progressive and invariably lethal interstitial lung disease with no effective therapy. We hypothesised that KCa3.1 K+ channel-dependent cell processes contribute to IPF pathophysiology.Methods
KCa3.1 expression in primary human lung myofibroblasts was examined using RT-PCR, western blot, immunofluorescence and patch-clamp electrophysiology. The role of KCa3.1 channels in myofibroblast proliferation, wound healing, collagen secretion and contraction was examined using two specific and distinct KCa3.1 blockers (TRAM-34 and ICA-17043 [Senicapoc]).Results
Both healthy non fibrotic control and IPF-derived human lung myofibroblasts expressed KCa3.1 channel mRNA and protein. KCa3.1 ion currents were elicited more frequently and were larger in IPF-derived myofibroblasts compared to controls. KCa3.1 currents were increased in myofibroblasts by TGFβ1 and basic FGF. KCa3.1 was expressed strongly in IPF tissue. KCa3.1 pharmacological blockade attenuated human myofibroblast proliferation, wound healing, collagen secretion and contractility in vitro, and this was associated with inhibition of TGFβ1-dependent increases in intracellular free Ca2+.Conclusions
KCa3.1 activity promotes pro-fibrotic human lung myofibroblast function. Blocking KCa3.1 may offer a novel approach to treating IPF with the potential for rapid translation to the clinic. 相似文献8.
Trine?H?JensenEmail author Gitte?Ajjouri Kurt?J?Handberg Marek?J?Slomka Vivien?J?Coward Martine?Cherbonnel Véronique?Jestin Peter?Lind Poul?H?J?rgensen 《Acta veterinaria Scandinavica》2013,55(1):84
Background
Avian influenza virus (AIV) subtypes H5 and H7 attracts particular attention because of the risk of their potential pathogenicity in poultry. The haemagglutination inhibition (HI) test is widely used as subtype specific test for serological diagnostics despite the laborious nature of this method. However, enzyme-linked immunosorbent assays (ELISAs) are being explored as an alternative test method.H5 and H7 specific monoclonal antibodies were experimentally raised and used in the development of inhibition ELISAs for detection of serological response specifically directed against AIV subtypes H5 and H7. The ELISAs were evaluated with polyclonal chicken anti-AIV antibodies against AIV subtypes: H1N2, H5N2, H5N7, H7N1, H7N7, H9N9, H10N4 and H16N3.Results
Both the H5 and H7 ELISA proved to have a high sensitivity and specificity and the ELISAs detected H5 and H7 antibodies earlier during experimental infection than the HI test did. The reproducibility of the ELISA’s performed at different times was high with Pearson correlation coefficients of 0.96-0.98.Conclusions
The ELISAs are a potential alternative to the HI test for screening of large amounts of avian sera, although only experimental sera were tested in this study.9.
This is not actually a swimming chicken, but rather a fish that fulfils a similar role for subsistence farmers and can also be farmed on a commercial scale. Like the chicken, the tilapiines are meeting protein needs in an affordable way world-wide. However, present farming strategies are struggling to meet ever-rising consumer demand. 相似文献
10.
The dynamics of proteins within large cellular assemblies are important in the molecular transformations that are required for macromolecular synthesis, transport, and metabolism. The capsid expansion (maturation) accompanying DNA packaging in the dsDNA bacteriophage P22 represents an experimentally accessible case of such a transformation. A novel method, based on hydrogen-deuterium exchange was devised to investigate the dynamics of capsid expansion. Mass spectrometric detection of deuterium incorporation allows for a sensitive and quantitative determination of hydrogen-deuterium exchange dynamics irrespective of the size of the assembly. Partial digestion of the exchanged protein with pepsin allows for region-specific assignment of the exchange. Procapsids and mature capsids were probed under native and slightly denaturing conditions. These experiments revealed regions that exhibit different degrees of flexibility in the procapsid and in the mature capsid. In addition, exchange and deuterium trapping during the process of expansion itself was observed and allowed for the identification of segments of the protein subunit that become buried or stabilized as a result of expansion. This approach may help to identify residues participating in macromolecular transformations and uncover novel patterns and hierarchies of interactions that determine functional movements within molecular machines. 相似文献