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101.
Hermann Cuntz Friedrich Forstner Bettina Schnell Georg Ammer Shamprasad Varija Raghu Alexander Borst 《PloS one》2013,8(8)
Important brain functions need to be conserved throughout organisms of extremely varying sizes. Here we study the scaling properties of an essential component of computation in the brain: the single neuron. We compare morphology and signal propagation of a uniquely identifiable interneuron, the HS cell, in the blowfly (Calliphora) with its exact counterpart in the fruit fly (Drosophila) which is about four times smaller in each dimension. Anatomical features of the HS cell scale isometrically and minimise wiring costs but, by themselves, do not scale to preserve the electrotonic behaviour. However, the membrane properties are set to conserve dendritic as well as axonal delays and attenuation as well as dendritic integration of visual information. In conclusion, the electrotonic structure of a neuron, the HS cell in this case, is surprisingly stable over a wide range of morphological scales. 相似文献
102.
Eliana Cordero Jan Rüger Dominik Marti Abdullah S. Mondol Thomas Hasselager Karin Mogensen Gregers G. Hermann Jürgen Popp Iwan W. Schie 《Journal of biophotonics》2020,13(2)
Existing approaches for early‐stage bladder tumor diagnosis largely depend on invasive and time‐consuming procedures, resulting in hospitalization, bleeding, bladder perforation, infection and other health risks for the patient. The reduction of current risk factors, while maintaining or even improving the diagnostic precision, is an underlying factor in clinical instrumentation research. For example, for clinic surveillance of patients with a history of noninvasive bladder tumors real‐time tumor diagnosis can enable immediate laser‐based removal of tumors using flexible cystoscopes in the outpatient clinic. Therefore, novel diagnostic modalities are required that can provide real‐time in vivo tumor diagnosis. Raman spectroscopy provides biochemical information of tissue samples ex vivo and in vivo and without the need for complicated sample preparation and staining procedures. For the past decade there has been a rise in applications to diagnose and characterize early cancer in different organs, such as in head and neck, colon and stomach, but also different pathologies, for example, inflammation and atherosclerotic plaques. Bladder pathology has also been studied but only with little attention to aspects that can influence the diagnosis, such as tissue heterogeneity, data preprocessing and model development. The present study presents a clinical investigative study on bladder biopsies to characterize the tumor grading ex vivo, using a compact fiber probe‐based imaging Raman system, as a crucial step towards in vivo Raman endoscopy. Furthermore, this study presents an evaluation of the tissue heterogeneity of highly fluorescent bladder tissues, and the multivariate statistical analysis for discrimination between nontumor tissue, and low‐ and high‐grade tumor. 相似文献
103.
B. Hermann 《Genetica》1973,44(4):579-587
The chromosome complement of Meriones tristrami Thomas (Rodentia, Gerbillinae), the Israel desert jird, studied by the new technique of chromosome identification (Q and G banding) is described. The diploid number is 72. There are two pairs of submetacentric autosomes (1 and 2) and 33 pairs of acrocentric autosomes. The X chromosome is the largest submetacentric and the Y is the fourth in length among the submetacentric chromosomes of the karyotype. The Fundamental Number (F.N.) is therefore 78 and not 76 as described by Matthey in 1957.
(Travail effectué avec l'appui du Fonds de la Recherche Scientifique Médicale). 相似文献
(Travail effectué avec l'appui du Fonds de la Recherche Scientifique Médicale). 相似文献
104.
105.
Edward B. Blanchard Maria L. Peters Christiane Hermann Shannon M. Turner Todd C. Buckley Kristine Barton Mark P. Dentinger 《Applied psychophysiology and biofeedback》1997,22(4):227-245
In order to test for the specific therapeutic effects of thermal biofeedback (TBF) for hand warming on vascular headache (HA),
70 patients with chronic vascular HA were randomly assigned to TBF for hand warming, TBF for hand cooling, TBF for stabilization
of hand temperature, or biofeedback to suppress alpha in the EEG. Patients in each condition initially had high levels of
expectation of therapeutic benefit and found the treatment rationales highly credible. Participants in each condition received
12 treatment sessions on a twice-per-week basis. Based on daily HA diary data gathered for 4 weeks prior to treatment and
4 weeks after treatment, HA Index was significantly (p=.003) reduced as was HA medication consumption. There were no differential
reducations in HA Index or Medication Index among the four conditions. Global self-reports of improvement gathered at the
end of the post-treatment monitoring period also did not differ among the four conditions. We were unable to demonstrate a
specific effect of TBF for hand warming on vascular HA activity. 相似文献
106.
Calcium-binding proteins were investigated immunohistochemically in chemo-receptors of the olfactory epithelium and taste buds of the clawed frog, Xenopus laevis. Calmodulin-, S-100- and calbindin-immunoreactive material were found in sensory cells of the olfactory epithelium; however, parvalbumin-like material was absent in these cells. Taste buds of the palate showed calmodulin-, S-100- and parvalbumin-immunoreactive material in sensory cells, while calbindin-immunoreactive material in supporting cells. Merkel cells, surrounding the base of the taste buds in a ring-like manner, exhibited calmodulin- and S-100-immunoreactive material. 相似文献
107.
Vélez Debora E. Mestre-Cordero Victoria E. Hermann Romina Perego Juliana Harriet Sofia Fernandez-Pazos María de las Mercedes Mourglia Julieta Marina-Prendes M. Gabriela 《Journal of physiology and biochemistry》2020,76(1):85-98
Journal of Physiology and Biochemistry - The cardioprotective activity of rosuvastatin (R) is yet to be known. The objective of this study was to research whether R perfusion before global ischemia... 相似文献
108.
Tserendorj Gegeensuvd Marinova Elena Lechterbeck Jutta Behling Hermann Wick Lucia Fischer Elske Sillmann Marion Märkle Tanja Rösch Manfred 《Vegetation History and Archaeobotany》2021,30(1):35-46
Vegetation History and Archaeobotany - A system of farming with an alternation of land use between being cultivated or left fallow as grassland (Feldgraswirtschaft) developed in southwestern... 相似文献
109.
Mario Gimona Maria Felice Brizzi Andre Boon Hwa Choo Massimo Dominici Sean M. Davidson Johannes Grillari Dirk M. Hermann Andrew F. Hill Dominique de Kleijn Ruenn Chai Lai Charles P. Lai Rebecca Lim Marta Monguió-Tortajada Maurizio Muraca Takahiro Ochiya Luis A. Ortiz Wei Seong Toh Yong Weon Yi Sai Kiang Lim 《Cytotherapy》2021,23(5):373-380
Mesenchymal stromal/stem cells (MSCs) have been widely tested against many diseases, with more than 1000 registered clinical trials worldwide. Despite many setbacks, MSCs have been approved for the treatment of graft-versus-host disease and Crohn disease. However, it is increasingly clear that MSCs exert their therapeutic functions in a paracrine manner through the secretion of small extracellular vesicles (sEVs) of 50–200 nm in diameter. Unlike living cells that can persist long-term, sEVs are non-living and non-replicative and have a transient presence in the body. Their small size also renders sEV preparations highly amenable to sterilization by filtration. Together, acellular MSC-sEV preparations are potentially safer and easier to translate into the clinic than cellular MSC products. Nevertheless, there are inherent challenges in the development of MSC-sEV drug products. MSC-sEVs are products of living cells, and living cells are sensitive to changes in the external microenvironment. Consequently, quality control metrics to measure key identity and potency features of MSC-sEV preparations have to be specified during development of MSC-sEV therapeutics. The authors have previously described quantifiable assays to define the identity of MSC-sEVs. Here the authors discuss requirements for prospective potency assays to predict the therapeutic effectiveness of the drug substance in accordance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines. Although potency assays should ideally reflect the mechanism of action (MoA), this is challenging because the MoA for the reported efficacy of MSC-sEV preparations against multiple diseases of diverse underlying pathology is likely to be complex and different for each disease and difficult to fully elucidate. Nevertheless, robust potency assays could be developed by identifying the EV attribute most relevant to the intended biological activity in EV-mediated therapy and quantifying the EV attribute. Specifically, the authors highlight challenges and mitigation measures to enhance the manufacture of consistent and reproducibly potent sEV preparations, to identify and select the appropriate EV attribute for potency assays despite a complex “work-in-progress” MoA and to develop assays likely to be compliant with regulatory guidance for assay validation. 相似文献
110.
Dieu T. X. Nguyen Hung Tran Stefan Schwaiger Hermann Stuppner Stefania Marzocco 《化学与生物多样性》2021,18(1):e2000577
The extract of Elsholtzia ciliata aerial parts was subjected to bio-guided isolation using the intercellular ROS reduction in J774A.1 macrophages to monitor the anti-oxidative activity. Fifteen compounds were isolated from the active fractions including eleven flavonoids (vitexin, pedalin, luteolin-7-O-β-d -glucopyranoside, apigenin-5-O-β-d -glucopyranoside, apigenin-7-O-β-d -glucopyranoside, chrysoeriol-7-O-β-d -glucopyranoside, 7,3′-dimethoxyluteolin-6-O-β-d -glucopyranoside, luteolin, 5,6,4′-trihydroxy-7,3′-dimethoxyflavone, 5-hydroxy-6,7-dimethoxyflavone (compound 13 ), 5-hydroxy-7,8-dimethoxyflavone); three hydroxycinnamic acid derivatives (caffeic acid, 4-(E)-caffeoyl-l -threonic acid, 4-O-(E)-p-coumaroyl-l -threonic acid) and one fatty acid (α-linolenic acid). The biological evaluation of these compounds (10–2.5 μm ) indicated that all of them exerted good antioxidant and anti-inflammatory activities, in particular compound 13 . 相似文献