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811.
The preload of the indiviuual myocardial fibers of the left ventricle, that is, the stress exerted upon the myocardial fibers
at end-diastole, is calculated by means of a set of equations. The development of the equations was based on anatomical data
referring to the shape of the left ventricle and the orientation of the myocardial fibers, as well as some assumptions of
minor importance. Numerical solution of the equations shows that in general, the preload increases as one advances from the
apex to the equator of the left ventricle and then it decreases as one advances toward the base. The preload also changes
as one advances from the epicardium to the endocardium in such a way that one can distinguish three zones: one outer, or epicardial,
with low preloads, one middle with high preloads and one inner, or endocardial, with low preloads. The physiological significance
of the findings as well as the validity of the assumptions on which the theory was based are discussed. 相似文献
812.
Panagiotis Giamougiannis Raissa V. O. Silva Daniel L. D. Freitas Kássio M. G. Lima Antonios Anagnostopoulos Georgios Angelopoulos Raj Naik Nicholas J. Wood Pierre L. Martin-Hirsch Francis L. Martin 《Journal of biophotonics》2021,14(11):e202100195
Blood plasma and serum Raman spectroscopy for ovarian cancer diagnosis has been applied in pilot studies, with promising results. Herein, a comparative analysis of these biofluids, with a novel assessment of urine, was conducted by Raman spectroscopy application in a large patient cohort. Spectra were obtained through samples measurements from 116 ovarian cancer patients and 307 controls. Principal component analysis identified significant spectral differences between cancers without previous treatment (n = 71) and following neo-adjuvant chemotherapy (NACT), (n = 45). Application of five classification algorithms achieved up to 73% sensitivity for plasma, high specificities and accuracies for both blood biofluids, and lower performance for urine. A drop in sensitivities for the NACT group in plasma and serum, with an opposite trend in urine, suggest that Raman spectroscopy could identify chemotherapy-related changes. This study confirms that biofluids' Raman spectroscopy can contribute in ovarian cancer's diagnostic work-up and demonstrates its potential in monitoring treatment response. 相似文献
813.
Apostolos P. Apostolidis Panagiotis K. Apostolou Andreas Georgiadis Raphael Sandaltzopoulos 《Conservation Genetics》2007,8(5):1025-1028
Analyses of the mtDNA control region sequence variation of the brown trout Salmo trutta through its distribution range have demonstrated five distinct phylogenetic lineages. In this work we report the design and
implementation of a rapid and accurate molecular diagnostic procedure which allows the assignment of all major phylogenetic
lineages. Our method relies on multiplex PCR that discriminates diagnostic single nucleotide polymorphisms (SNPs) characteristic
of each lineage. The method is straightforward and easy to set up, involves a single reaction, yields data easy to interpret
and does not pose significant risk for false positive/negative lineage assignment of a given individual.
Panagotis K. Apostolou and Andreas Georgiadis contributed equally to this work. 相似文献
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Endoplasmic reticulum (ER) immunolabeling in developing stomatal complexes and in the intervening cells of the stomatal rows
(ICSRs) of Zea mays revealed that the cortical-ER forms distinct aggregations lining locally expanding wall regions. The polarized subsidiary
cell mother cells (SMCs), displayed a cortical-ER-patch lining the wall region shared with the inducing guard cell mother
cell (GMC), which disorganized during mitosis. In dividing SMCs, ER persisted in the preprophase band region and was unequally
distributed in the mitotic spindle poles. The subsidiary cells (SCs) formed initially an ER-patch lining the common wall with
the GMC or the young guard cells and afterwards an ER-ring in the junction of the SC wall with the neighboring ones. Distinct
ER aggregations lined the ICSR wall regions shared with the SCs. The cortical-ER aggregations in stomatal cells of Z. mays were co-localized with actin filament (AF) arrays but both were absent from the respective cells of Triticum turgidum, which follow a different morphogenetic pattern. Experimental evidence showed that the interphase ER aggregations are organized
by the respective AF arrays, while the mitotic ER aggregations by microtubules. These results revealed that AF and ER demarcated
“cortical cytoplasmic domains” are activated below the locally expanding stomatal cell wall regions, probably via a mechanosensing
mechanism triggered by the locally stressed plasmalemma/cell wall continuum. The probable role(s) of the local ER aggregations
are discussed. 相似文献
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820.
Charles H. Washabaugh Katia Del Rio-Tsonis Panagiotis A. Tsonis 《Journal of morphology》1993,218(1):107-114
We describe a detailed histological analysis of the affected organs in the Short toes (s) mutation of the Mexican axolotl, Ambystoma mexicanum. The s mutant animals displayed a variation in the response to the mutation such as the time of death and the degree of abnormalities of the affected organs (limbs, kidney, ducts, and reproductive structures). In addition to the numerous histological abnormalities characterized here, we also examined the presence of laminin-related molecules in s mutant kidney tissues to elucidate further the nature of the renal aplasia these animals encounter as a result of this recessive lethal mutation. Our data suggest that there may be a disruption in tissue interactions necessary for proper development and functioning of the affected tissues. © 1993 Wiley-Liss, Inc. 相似文献