全文获取类型
收费全文 | 95篇 |
免费 | 6篇 |
专业分类
101篇 |
出版年
2021年 | 3篇 |
2020年 | 2篇 |
2018年 | 2篇 |
2017年 | 1篇 |
2016年 | 2篇 |
2015年 | 4篇 |
2014年 | 2篇 |
2013年 | 2篇 |
2012年 | 4篇 |
2011年 | 8篇 |
2010年 | 3篇 |
2009年 | 1篇 |
2008年 | 1篇 |
2007年 | 2篇 |
2006年 | 3篇 |
2005年 | 4篇 |
2004年 | 3篇 |
2003年 | 1篇 |
2002年 | 1篇 |
2001年 | 1篇 |
2000年 | 2篇 |
1999年 | 1篇 |
1998年 | 1篇 |
1997年 | 2篇 |
1995年 | 1篇 |
1991年 | 1篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 3篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 7篇 |
1982年 | 4篇 |
1981年 | 3篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 1篇 |
1976年 | 1篇 |
1975年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1933年 | 1篇 |
1918年 | 1篇 |
排序方式: 共有101条查询结果,搜索用时 0 毫秒
1.
Cyclo (His-Pro) (10 ng/ml), inhibits KCl (59 mM) or thyrotropin-releasing hormone (10 ng/ml) stimulated, but not basal, release of prolactin from rat hemipituitaries . However, cyclo (His-Pro) has no effect on the basal or stimulated release of thyrotropin and growth hormone. Cyclo (His-Pro) does not inhibit the binding of thyrotropin-releasing hormone to pituitary membrane suggesting that cyclo (His-Pro) inhibition of prolactin release is not mediated via the pituitary TRH-receptor. 相似文献
2.
3.
4.
Pathogen persistence in host communities is influenced by processes operating at the individual host to landscape‐level scale, but isolating the relative contributions of these processes is challenging. We developed theory to partition the influence of host species, habitat patches and landscape connectivity on pathogen persistence within metacommunities of hosts and pathogens. We used this framework to quantify the contributions of host species composition and habitat patch identity on the persistence of an amphibian pathogen across the landscape. By sampling over 11 000 hosts of six amphibian species, we found that a single host species could maintain the pathogen in 91% of observed metacommunities. Moreover, this dominant maintenance species contributed, on average, twice as much to landscape‐level pathogen persistence compared to the most influential source patch in a metacommunity. Our analysis demonstrates substantial inequality in how species and patches contribute to pathogen persistence, with important implications for targeted disease management. 相似文献
5.
Distribution and characterization of cyclo(His-Pro)-like immunoreactivity in the rat gastrointestinal tract 总被引:1,自引:0,他引:1
M Mori J Pegues C Prasad R M Edwards J F Wilber 《Biochemical and biophysical research communications》1982,109(3):982-987
The distribution of cyclo(His-Pro), thyrotropin-releasing hormone (TRH) and activity was examined in the rat gastrointestinal (GI) tract. Cyclo(His-Pro)-like immunoreactivity was present in the following order of distribution (fmoles/mg protein): caecum > colon = jejunum = ileum > stomach = duodenum = rectum, and was immunologically and chromatographically identical with the authentic cyclo(His-Pro). Cyclo(His-Pro) concentrations showed significantly positive correlations with TRH concentrations, but not with activities, in most tissues of the GI tract, suggesting a precursor role of TRH for gut cyclo(His-Pro). These data suggest that cyclo(His-Pro) may be involved in regulating rat GI functions. 相似文献
6.
Borroto-Escuela DO Romero-Fernandez W Tarakanov AO Marcellino D Ciruela F Agnati LF Fuxe K 《Biochemical and biophysical research communications》2010,401(4):605-610
In view of the co-distribution of dopamine D2LR and 5-hydroxytryptamine 5-HT2A receptors (D2LR and 5-HT2AR, respectively) within inter alia regions of the dorsal and ventral striatum and their role as a target of antipsychotic drugs; in this study we assessed the potential existence of D2LR-5-HT2AR heteromers in living cells and the functional consequences of this interaction. Thus, by means of a proximity-based bioluminescence resonance energy transfer (BRET) approach we demonstrated that the D2LR and the 5-HT2AR form stable and specific heteromers when expressed in HEK293T mammalian cells. Furthermore, when the D2LR-5-HT2AR heteromeric signaling was analyzed we found that the 5-HT2AR-mediated phospholipase C (PLC) activation was synergistically enhanced by the concomitant activation of the D2LR as shown in a NFAT-luciferase reporter gene assay and a specific and significant rise of the intracellular calcium levels were observed when both receptors were simultaneously activated. Conversely, when the D2LR-mediated adenylyl cyclase (AC) inhibition was assayed we showed that costimulation of D2LR and 5-HT2AR within the heteromer led to inhibition of the D2LR functioning, thus suggesting the existence of a 5-HT2AR-mediated D2LR trans-inhibition phenomenon. Finally, a bioinformatics study reveals that the triplet amino acid homologies LLT (Leu-Leu-Thr) and AIS (Ala-Ile-Ser) in TM1 and TM3, respectively of the D2R-5-HT2AR may be involved in the receptor interface. Overall, the presence of the D2LR-5-HT2AR heteromer in discrete brain regions is postulated based on the existence of D2LR-5-HT2A receptor-receptor interactions in living cells and their codistribution inter alia in striatal regions. Possible novel therapeutic strategies for treatment of schizophrenia should be explored by targeting this heteromer. 相似文献
7.
Borroto-Escuela DO Romero-Fernandez W García-Negredo G Correia PA Garriga P Fuxe K Ciruela F 《Cellular physiology and biochemistry》2011,28(5):1009-1022
Acetylcholine challenge produces M(3) muscarinic acetylcholine receptor activation and accessory/scaffold proteins recruitment into a signalsome complex. The dynamics of such a complex is not well understood but a conserved NPxxY motif located within transmembrane 7 and juxtamembrane helix 8 of the receptor was found to modulate G protein activation. Here by means of receptor mutagenesis we unravel the role of the conserved M(3) muscarinic acetylcholine receptor NPxxY motif on ligand binding, signaling and multiprotein complex formation. Interestingly, while a N7.49D receptor mutant showed normal ligand binding properties a N7.49A mutant had reduced antagonist binding and increased affinity for carbachol. Also, besides this last mutant was able to physically couple to Gα(q/11) after carbachol challenge it was neither capable to activate phospholipase C nor phospholipase D. On the other hand, we demonstrated that the Asn-7.49 is important for the interaction between M(3)R and ARF1 and also for the formation of the ARF/Rho/β γ signaling complex, a complex that might determine the rapid activation and desensitization of PLD. Overall, these results indicate that the NPxxY motif of the M(3) muscarinic acetylcholine receptor acts as key conformational switch for receptor signaling and multiprotein complex formation. 相似文献
8.
Glycoprotein D (gD-2) is the entry receptor of herpes simplex virus 2 (HSV-2), and is the immunogen in the pharmaceutical industry''s lead HSV-2 vaccine candidate. Efforts to prevent genital herpes using gD-2 subunit vaccines have been ongoing for 20 years at a cost in excess of $100 million. To date, gD-2 vaccines have yielded equivocal protection in clinical trials. Therefore, using a small animal model, we sought to determine if a live-attenuated HSV-2 ICP0
− virus would elicit better protection against genital herpes than a gD-2 subunit vaccine. Mice immunized with gD-2 and a potent adjuvant (alum+monophosphoryl lipid A) produced high titers of gD-2 antibody. While gD-2-immunized mice possessed significant resistance to HSV-2, only 3 of 45 gD-2-immunized mice survived an overwhelming challenge of the vagina or eyes with wild-type HSV-2 (MS strain). In contrast, 114 of 115 mice immunized with a live HSV-2 ICP0
− virus, 0ΔNLS, survived the same HSV-2 MS challenges. Likewise, 0ΔNLS-immunized mice shed an average 125-fold less HSV-2 MS challenge virus per vagina relative to gD-2-immunized mice. In vivo imaging demonstrated that a luciferase-expressing HSV-2 challenge virus failed to establish a detectable infection in 0ΔNLS-immunized mice, whereas the same virus readily infected naïve and gD-2-immunized mice. Collectively, these results suggest that a HSV-2 vaccine might be more likely to prevent genital herpes if it contained a live-attenuated HSV-2 virus rather than a single HSV-2 protein. 相似文献
9.
10.
Surveillance of DNA damage and maintenance of lipid metabolism are critical factors for general cellular homeostasis. We discovered that in response to DNA damage–inducing UV light exposure, intact Caenorhabditis elegans accumulate intracellular lipids in a dose-dependent manner. The increase in intracellular lipids in response to exposure to UV light utilizes mafr-1, a negative regulator of RNA polymerase III and the apical kinases atm-1 and atl-1 of the DNA damage response (DDR) pathway. In the absence of exposure to UV light, the genetic ablation of mafr-1 results in the activation of the DDR, including increased intracellular lipid accumulation, phosphorylation of ATM/ATR target proteins, and expression of the Bcl-2 homology region genes, egl-1 and ced-13. Taken together, our results reveal mafr-1 as a component the DDR pathway response to regulating lipid homeostasis following exposure to UV genotoxic stress. 相似文献