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221.
Qian Zhang Yunjiang Feng Derek Kennedy 《Cellular and molecular life sciences : CMLS》2017,74(5):777-801
Chemotherapy is one of the most effective and broadly used approaches for cancer management and many modern regimes can eliminate the bulk of the cancer cells. However, recurrence and metastasis still remain a major obstacle leading to the failure of systemic cancer treatments. Therefore, to improve the long-term eradication of cancer, the cellular and molecular pathways that provide targets which play crucial roles in drug resistance should be identified and characterised. Multidrug resistance (MDR) and the existence of tumor-initiating cells, also referred to as cancer stem cells (CSCs), are two major contributors to the failure of chemotherapy. MDR describes cancer cells that become resistant to structurally and functionally unrelated anti-cancer agents. CSCs are a small population of cells within cancer cells with the capacity of self-renewal, tumor metastasis, and cell differentiation. CSCs are also believed to be associated with chemoresistance. Thus, MDR and CSCs are the greatest challenges for cancer chemotherapy. A significant effort has been made to identify agents that specifically target MDR cells and CSCs. Consequently, some agents derived from nature have been developed with a view that they may overcome MDR and/or target CSCs. In this review, natural products-targeting MDR cancer cells and CSCs are summarized and clustered by their targets in different signaling pathways. 相似文献
222.
Derek D. Turner 《Studies in history and philosophy of science》2004,35(1):1-17
Scientific realism is fundamentally a view about unobservable things, events, processes, and so on, but things can be unobservable either because they are tiny or because they are past. The familiar abductive arguments for scientific realism lend more justification to scientific realism about the tiny than to realism about the past. This paper examines both the “basic” abductive arguments for realism advanced by philosophers such as Ian Hacking and Michael Devitt, as well as Richard Boyd’s version of the inference to the best explanation of the success of science, and shows that these arguments provide less support to historical than to experimental realism. This is because unobservably tiny things can function both as unifiers of the phenomena and as tools for the production of new phenomena, whereas things in the past can only serve as unifiers of the phenomena. The upshot is that realists must not suppose that by presenting arguments for experimental realism they have thereby defended realism in general. 相似文献
223.
Weir BA Woo MS Getz G Perner S Ding L Beroukhim R Lin WM Province MA Kraja A Johnson LA Shah K Sato M Thomas RK Barletta JA Borecki IB Broderick S Chang AC Chiang DY Chirieac LR Cho J Fujii Y Gazdar AF Giordano T Greulich H Hanna M Johnson BE Kris MG Lash A Lin L Lindeman N Mardis ER McPherson JD Minna JD Morgan MB Nadel M Orringer MB Osborne JR Ozenberger B Ramos AH Robinson J Roth JA Rusch V Sasaki H Shepherd F Sougnez C Spitz MR Tsao MS Twomey D Verhaak RG Weinstock GM Wheeler DA Winckler W 《Nature》2007,450(7171):893-898
224.
SMRT-mediated repression of an H3K27 demethylase in progression from neural stem cell to neuron 总被引:3,自引:0,他引:3
Jepsen K Solum D Zhou T McEvilly RJ Kim HJ Glass CK Hermanson O Rosenfeld MG 《Nature》2007,450(7168):415-419
225.
Leon Bly Tunnel, which connects Eagle Lake to Willow Creek, was investigated to see if the water issuing from the tunnel was lake water or spring water and to check reports of its being inhabited by fish. We found that the water was similar to that of highly alkaline Eagle Lake, despite a block placed in the tunnel in 1986. Five species of fish were found in the tunnel, the same species inhabiting both Willow Creek and Eagle Lake, although the creek was much warmer and less alkaline than the lake. The fish originated from the creek. Fish in the tunnel were either not feeding or were consuming snails ( Vorticifex sp.), the principal invertebrate present. The largest fish (35 cm SL) captured were rainbow trout ( Oncorhynchus mykiss ). 相似文献
226.
Explanations implicitly end with something that makes sense, and begin with something that does not make sense. A statistical relationship, for example, a numerical fact, does not make sense; an explanation of this relationship adds something, such as causal information, which does make sense, and provides an endpoint for the sense-making process. Does social science differ from natural science in this respect? One difference is that in the natural sciences, models are what need “understanding.” In the social sciences, matters are more complex. There are models, such as causal models, which need to be understood, but also depend on background knowledge that goes beyond the model and the correlations that make it up, which produces a regress. The background knowledge is knowledge of in-filling mechanisms, which are normally made up of elements that involve the direct understanding of the acting and believing subjects themselves. These models, and social science explanations generally, are satisfactory only when they end the regress in this kind of understanding or use direct understanding evidence to decide between alternative mechanism explanations. 相似文献
227.
Daniel W. Lambert Nicola E. Clarke Anthony J. Turner 《Cellular and molecular life sciences : CMLS》2010,67(1):89-98
The renin-angiotensin system (RAS) is a critical regulator of blood pressure and fluid homeostasis. Angiotensin II, the primary
bioactive peptide of the RAS, is generated from angiotensin I by angiotensin-converting enzyme (ACE). A homologue of ACE,
ACE2, is able to convert angiotensin II to a peptide with opposing effects, angiotensin-(1-7). It is proposed that disturbance
of the balance of ACE and ACE2 expression and/or function is important in pathologies in which angiotensin II plays a role.
These include cardiovascular and renal disease, lung injury and liver fibrosis. The critical roles of ACE and ACE2 in regulating
angiotensin II levels have traditionally focussed attention on their activities as angiotensinases. Recent discoveries, however,
have illuminated the roles of these enzymes and of the ACE2 homologue, collectrin, in intracellular trafficking and signalling.
This paper reviews the key literature regarding both the catalytic and non-catalytic roles of the angiotensin-converting enzyme
gene family. 相似文献
228.
本书既注重理论性,又具有实用性。作者深入浅出地介绍了生物学研究中最常见的并且是新的计算机深入分析的方法,这些现代计算方法使数据分析不再依赖于先验假设。作者在本书中有针对性地设计了一些练习,并给出了参考答案,读者可通过做习题、对答案,检查自己对书中内容的理解。作者在该书中给出的例子都来源于实际的生物学研究, 相似文献
229.
Albers CA Paul DS Schulze H Freson K Stephens JC Smethurst PA Jolley JD Cvejic A Kostadima M Bertone P Breuning MH Debili N Deloukas P Favier R Fiedler J Hobbs CM Huang N Hurles ME Kiddle G Krapels I Nurden P Ruivenkamp CA Sambrook JG Smith K Stemple DL Strauss G Thys C van Geet C Newbury-Ecob R Ouwehand WH Ghevaert C 《Nature genetics》2012,44(4):435-9, S1-2
230.
Hunt KA Zhernakova A Turner G Heap GA Franke L Bruinenberg M Romanos J Dinesen LC Ryan AW Panesar D Gwilliam R Takeuchi F McLaren WM Holmes GK Howdle PD Walters JR Sanders DS Playford RJ Trynka G Mulder CJ Mearin ML Verbeek WH Trimble V Stevens FM O'Morain C Kennedy NP Kelleher D Pennington DJ Strachan DP McArdle WL Mein CA Wapenaar MC Deloukas P McGinnis R McManus R Wijmenga C van Heel DA 《Nature genetics》2008,40(4):395-402
Our genome-wide association study of celiac disease previously identified risk variants in the IL2-IL21 region. To identify additional risk variants, we genotyped 1,020 of the most strongly associated non-HLA markers in an additional 1,643 cases and 3,406 controls. Through joint analysis including the genome-wide association study data (767 cases, 1,422 controls), we identified seven previously unknown risk regions (P < 5 x 10(-7)). Six regions harbor genes controlling immune responses, including CCR3, IL12A, IL18RAP, RGS1, SH2B3 (nsSNP rs3184504) and TAGAP. Whole-blood IL18RAP mRNA expression correlated with IL18RAP genotype. Type 1 diabetes and celiac disease share HLA-DQ, IL2-IL21, CCR3 and SH2B3 risk regions. Thus, this extensive genome-wide association follow-up study has identified additional celiac disease risk variants in relevant biological pathways. 相似文献