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451.
Yonat Milstein Michal Tepper Moshe Ben David James A. Harrington Israel Gannot 《Journal of biophotonics》2011,4(4):219-223
This study objective is to validate a method for the measurement of two compound phantoms as a proof of concept for oxygen saturation level measurement via a thermal imaging bundle. The method consists of a thermal imaging system and an algorithm which estimates the compound concentration according to temperature rise. A temperature rise is obtained by illuminating the tissue with a laser with different wavelengths in the NIR range and measured using a thermal camera. A coherent thermal imaging bundle was used for image transmittance for minimal invasive transendoscopic use. The algorithm's estimation ability was evaluated using agar phantoms of varying Methylene Blue and ICG ratios as well as blood samples The Methylene Blue ratio in each phantom was estimated and the calculated average RMS of the error was 9.38%, a satisfying value for this stage, verifying the algorithm's and bundle's suitability for the use in a minimal invasive system. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
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453.
《Endocrine practice》2023,29(3):221-227
A better understanding of the molecular aberrations prevalent in thyroid cancers had led to significant advances in the management of advanced thyroid cancer. The landscape of thyroid cancer treatment has grown rapidly. Molecular profiling is the key to identify actionable targets for treatment of advanced disease. In the past decade, there have been regulatory approvals of 9 kinase inhibitors or kinase inhibitor combinations. There are now drugs approved for all of the different types of thyroid cancers, including anaplastic thyroid cancer. However, these drugs are not curative and therefore new strategies and treatments continue to be sought. 相似文献
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455.
Fernando Rodríguez-Pérez Andrew G. Manford Angela Pogson Andrew J. Ingersoll Brenda Martínez-González Michael Rape 《Developmental cell》2021,56(5):588-601.e9
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456.
Ziv Attia Ahan Dalal Menachem Moshelion 《The Plant journal : for cell and molecular biology》2020,101(6):1368-1377
Plants can detect pathogen invasion by sensing microbe‐associated molecular patterns (MAMPs). This sensing process leads to the induction of defense responses. Numerous MAMP mechanisms of action have been described in and outside the guard cells. Here, we describe the effects of chitin, a MAMP found in fungal cell walls and insects, on the cellular osmotic water permeability (Pf) of the leaf vascular bundle‐sheath (BS) and mesophyll cells (MCs), and its subsequent effect on leaf hydraulic conductance (Kleaf). BS is a parenchymatic tissue that tightly encases the vascular system. BS cells (BSCs) have been shown to influence Kleaf through changes in their Pf, for example, after sensing the abiotic stress response‐regulating hormone abscisic acid. It was recently reported that, in Arabidopsis, the chitin receptors‐like kinases, chitin elicitor receptor kinase 1 (CERK1) and LYSINE MOTIF RECEPTOR KINASE 5 (LYK5) are highly expressed in the BS as well as the neighboring mesophyll. Therefore, we studied the possible impact of chitin on these cells. Our results revealed that BSCs and MCs exhibit a sharp decrease in Pf in response to chitin treatment. In addition, xylem‐fed chitin decreased Kleaf and led to stomatal closure. However, Atlyk5 mutant showed none of these responses. Complementing AtLYK5 in the BSCs (using the SCARECROW promoter) resulted in the response to chitin that was similar to that observed in the wild‐type. These results suggest that BS play a role in the perception of apoplastic chitin and in initiating chitin‐triggered immunity. 相似文献
457.
Extracellular fluid levels of dopamine and neurotensin in the rat prefrontal cortex were measured using in vivo microdialysis. Electrical stimulation of the median forebrain bundle resulted in increased release of both dopamine and neurotensin from the prefrontal cortex. Thus, stimulation of neurons in which dopamine and neurotensin are colocalized can evoke the in vivo release of both substances. 相似文献
458.
《Genomics》2022,114(2):110302
The genetic origins of novelty are of central interest in evolutionary biology. ISG15 and UBA7 are present only in vertebrates. The emergence and evolution of them are not clear. Phylogenetic comparisons revealed that UBA7 descends from gene duplication, and ISG15 and UBA7 arose from UBB/UBC and UBA1, respectively. Uba7 exhibits ubiquitin-activation activity in fish but not tetrapods, suggesting that the relationship of ISG15/Uba7 was promiscuous in origin but was later coopted toward higher specificity. Zebrafish Uba7 is capable of activating the ubiquitin cascade in vitro and in vivo, and it displays distinct specificity preference toward substrates and E2 enzymes compared to zebrafish Uba1. These results together provide a framework for understanding the origin and diversification of ISG15/Uba7 and may serve as a paradigmatic example in which an originally minor functionality in an old gene is made into a new high-specificity protein through random mutations and natural selection. 相似文献
459.
Richard A. Zager Dennis J. Gmur Charles R. Bredl Mary J. Eng Lloyd Fisher 《Biochimica et Biophysica Acta (BBA)/General Subjects》1990,1035(1):29-36
Renal cortex (C) has predominantly aerobic metabolism, whereas inner medulla (IM) has both aerobic and anaerobic capacities. This study was undertaken (1) to assess how well rat IM anaerobic metabolism maintains this region's ATP content during ischemia; and (2) to determine whether regional variations in adenylate pool/catabolite responses to ischemia exist, obscuring interpretation of cellular energetics in rat studies of acute renal failure (ARF). Adenine nucleotides/catabolites were measured in rat C, IM and outer medulla (OM) after 15 and 45 min of ischemia. After 15 min, all regions showed profound ATP depletion, although the IM maintained slightly higher (by 0.23 μmol/g) absolute ATP levels than C/OM tissues (normal ATP value = 8.7 μmol/g). By 45 min, significant differences in regional ATP levels did not exist. Striking regional catabolite differences were apparent at both 15 and 45 min. Most prominent were: (1) intrarenal purine base/inosine gradients, levels falling approx. 22–50% from C to IM; and (2) preferential OM AMP/IMP/adenosine accumulation. To assess whether more homogeneous results might be found in rabbit kidney, possibly making this animal preferable to rats for studies of renal ischemia, rabbit C, OM and IM adenylate pools were analyzed after 15 min of ischemia. C vs. IM ATP differences were greater (approx. 1.3 μmol/g) and large catabolite concentration differences were still apparent. Conclusions: (1) anaerobic mechanisms support IM ATP levels during ischemia but, in terms of normal concentrations, the impact is small, particularly in the rat; and (2) marked regional differences in adenylate catabolite levels exist within ischemic kidneys. These need to be recognized when analyzing adenylate pool responses in ischemic ARF. 相似文献
460.