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351.
The Jahrum Formation was deposited in the foreland basin in southwest Iran (Zagros Basin). The Zagros mountain belt of Iran, a part of the Alpine–Himalayan system, extends from the NW Iranian border through to SW Iran, up to the strait of Hormuz. The various facies of the Jahrum Formation were deposited in four main genetically related depositional environments, including: tidal flat, lagoon, shoal and open marine. These are represented by 14 microfacies. The Jahrum Formation represents sedimentation on a carbonate ramp. Tidal flat facies are represented by fenestral fabric, stromatolitic boundstone and thin-bedded planes. Carbonate deposition in a shallow marine lagoon was characterised by wacke–packstone, dominated by various taxa of imperforate foraminifer. The shoals are made up of medium- to coarse-grained skeletal and peloidal grainstone. This facies was deposited predominantly in an active high energy wave and current regime, and grades basinward into middle ramps facies are represented by wackestones–packstones with a diverse assemblage of echinoderm and large benthic foraminifers with perforate wall. Outer ramp facies consist of alternating marl and limestones rich in pelagic foraminifera. There is no evidence for resedimentation processes in this facies belt. The sequence stratigraphy study has led to recognition of three third-order depositional sequences.  相似文献   
352.
Platform carbonate sediments of Oligocene–Miocene age (Asmari Formation) in the Zagros Basin (SW Iran) have been investigated in order to determine their paleoecology and depositional environment. The Zagros Basin is the result of the opening and closure of the Neo-Tethys Ocean along the northeastern border of the Arabian Plate. The thick sedimentary sequences of the Zagros Basin contain rocks ranging in age from Cambrian to recent. The geological evidence suggests that the region was part of a passive continental margin, which subsequently underwent rifting in the Permo-Trias and collision in the Late Tertiary. The Asmari carbonate system was dominated by foraminifera and corallinacean assemblage. Based on the distribution of the larger foraminifera, four assemblage zones have been recognised. Facies analysis allowed the recognition of nine microfacies types that are grouped into three depositional environments that correspond to the inner, middle and outer shelf. The biota assemblage of the Asmari Formation suggests that carbonate sedimentation took place in tropical waters and oligotrophic to slightly mesotrophic conditions. Our detailed analysis of microfacies and paleoecology shows that the Asmari Formation deposited on a carbonate open shelf dominated by heterozoan and, subordinately, photozoan skeletal assemblage.  相似文献   
353.
Background:Cyclooxygenase-2 (COX-2) main product is Prostaglandin E2 (PGE2) which cause mitogenesis and inflammation. COX-2 is the product of prostaglandin-endoperoxide synthase 2 (PTGS2) gene expression. COX-2 dysregulation can cause angiogenesis, differentiation, and promotion of cancer and its suppression related to control of the tumor''s size, number, and cell shape. This study focused on the association of COX-2 expression with colorectal carcinoma (CRC) among Iranian patients on mRNA level and in the Cancer Genome Atlas Program (TCGA) colon and rectum RNAseq dataset, and its relation with pathological features.Methods:PTGS2 expression was assayed by quantitative-PCR method from 90 tissue samples collected from 45 participants. The control samples come from the non-tumor area of the same patients. The data analyzed based on ΔΔCq. The PTGS2-RNAseq data extracted and analyzed by UCSC Xena browser, and its association assessed the occurrence of CRC and invasive-features.Results:PTGS2 showed very significant over-expression in tumor tissues (p< 0.0001) with an N-fold expression of 2.25. But, there was not any significant association between PTGS2 and CRC invasive-pathological features such as Lymphatic, vascular and perineural invasion, the Grades of cancer, and Pathologic-M in both parts of this study.Conclusion:The increase in PTGS2 is related to the occurrence of CRC among patient samples. But in both part of this study, PTGS2 is not an invasive factor, and it does not affect the cell differentiation of tumors and metastasis. Based on the high N-fold for patient samples, it can be a strong candidate as a CRC initiator biomarker.Key Words: : Cyclooxygenase-2, Gene expression profiling, Neoplasm invasion, Prostaglandins, TCGA-data  相似文献   
354.
Our traditional physical picture holds with the intuitive notion that each individual cell comprising the cellular collective senses signals or gradients and then mobilizes physical forces in response. Those forces, in turn, drive local cellular motions from which collective cellular migrations emerge. Although it does not account for spontaneous noisy fluctuations that can be quite large, the tacit assumption has been one of linear causality in which systematic local motions, on average, are the shadow of local forces, and these local forces are the shadow of the local signals. New lines of evidence now suggest a rather different physical picture in which dominant mechanical events may not be local, the cascade of mechanical causality may be not so linear, and, surprisingly, the fluctuations may not be noise as much as they are an essential feature of mechanism. Here we argue for a novel synthesis in which fluctuations and non-local cooperative events that typify the cellular collective might be illuminated by the unifying concept of cell jamming. Jamming has the potential to pull together diverse factors that are already known to contribute but previously had been considered for the most part as acting separately and independently. These include cellular crowding, intercellular force transmission, cadherin-dependent cell–cell adhesion, integrin-dependent cell–substrate adhesion, myosin-dependent motile force and contractility, actin-dependent deformability, proliferation, compression and stretch.  相似文献   
355.

Traumatic brain injury (TBI) is known as an acute degenerative pathology of the central nervous system, and has been shown to increase brain aquaporin 4 (AQP4) expression. Various molecular mechanisms affect AQP4 expression, including neuronal high mobility group box 1, forkhead box O3a, vascular endothelial growth factor, hypoxia-inducible factor-1 α (HIF-1 α) sirtuin 2, NF-κB, Malat1, nerve growth factor and Angiotensin II receptor type 1. In addition, inhibition of AQP4 with FK-506, MK-801 (indirectly by targeting N-methyl-d-aspartate receptor), inactivation of adenosine A2A receptor, levetiracetam, adjudin, progesterone, estrogen, V1aR inhibitor, hypertonic saline, erythropoietin, poloxamer 188, brilliant blue G, HIF-1alpha inhibitor, normobaric oxygen therapy, astaxanthin, epigallocatechin-3-gallate, sesamin, thaliporphine, magnesium, prebiotic fiber, resveratrol and omega-3, as well as AQP4 gene silencing lead to reduced edema upon TBI. This review summarizes current knowledge and evidence on the relationship between AQP4 and TBI, and the potential mechanisms involved.

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356.
The objective of this work was to investigate the particle size and determine the catalytic competency of a solubilized lipase in hexane. Purified Candida antarctica lipase B (CALB) was solubilized in hexane using the non-ionic surfactant Span 60. The amount of surfactant was chosen so that complete coverage of the individual enzyme molecules with surfactant was not possible. Dynamic Light Scattering (DLS) was used to directly investigate the particle size of the solubilized entities. The enzyme was found to be solubilized in the form of clusters of lipase molecules with a radius of 37±5 nm at 42°C, which we estimate to correspond to about 1200 CALB molecules. The solubilized enzyme clusters showed lower catalytic activity in a model esterification reaction in hexane compared with a commercial immobilizate of the same enzyme (Novozym 435). Further gains in catalytic activity may be possible by striving for true molecular-level dispersion of the enzyme in hexane.  相似文献   
357.
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