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431.
432.
Discrepancies and errors in the taxonomic and nomenclatural treatment of Primula auricula complex by Zhang (2002) and Zhang & Kadereit (2004, 2005) are discussed. Investigation of a few hundred P. auricula specimens stored in BP yielded contradictory morphological results compared with those of the above authors. In contrast
with the key proposed by them specimens (BP) from Mt Domogledu (Romania) have short, while those from the north Carpathians
(Slovakia) have relatively long glandular hairs on the leafmargins. Lectotypes of P. auricula var. serratifolia Rochel ex Borbás and P. auricula var. hungarica Borbás are designated. Nomenclatural errors made by Zhang and Kadereit are corrected, and it is emphasized that the name
P. lutea ssp. tatriaca applied for Slovak populations by them is superfluous. Further researches are needed to clarify the taxonomic position of
Slovak and Romanian P. auricula populations. Morphological characters considered as distinctive and relevant by Zhang and Kadereit seem to be dependent on
the phenological state of plants. 相似文献
433.
L Keszthelyi 《Origins of life》1984,14(1-4):375-382
434.
Zolt��n Varecza Kriszti��n Elekes Ter��zia L��szl�� Anik�� Perkecz Erika Pint��r Zolt��n S��ndor J��nos Szolcs��nyi D��niel Keszthelyi ��rp��d Szab�� Katalin S��ndor Tam��s F. Moln��r Zal��n Sz��nt�� Judit E. Pongr��cz Zsuzsanna Helyes 《The journal of histochemistry and cytochemistry》2009,57(12):1127-1137
Somatostatin released from capsaicin-sensitive sensory nerves of the lung during endotoxin-induced murine pneumonitis inhibits inflammation and hyperresponsiveness, presumably via somatostatin receptor subtype 4 (sst4). The goal of the present study was to identify sst4 receptors in mouse and human lungs and to reveal its inflammation-induced alterations with real-time quantitative PCR, Western blot, and immunohistochemistry. In non-inflamed mouse and human lungs, mRNA expression and immunolocalization of sst4 are very similar. They are present on bronchial epithelial, vascular endothelial, and smooth-muscle cells. The sst4 receptor protein in the mouse lung significantly increases 24 hr after intranasal endotoxin administration as well as in response to 3 months of whole-body cigarette smoke exposure, owing to the infiltrating sst4-positivite mononuclear cells and neutrophils. In the chronically inflamed human lung, the large number of activated macrophages markedly elevate sst4 mRNA levels, although there is no change in acute purulent pneumonia, in which granulocytes accumulate. Despite mouse granulocytes, human neutrophils do not show sst4 immunopositivity. We provide the first evidence for the expression, localization, and inflammation-induced alterations of sst4 receptors in murine and human lungs. Inasmuch as tissue distribution of this receptor is highly similar, extrapolation of murine experimental results to human conditions might be possible. (J Histochem Cytochem 57:1127–1137, 2009) 相似文献
435.
Deuteron spin-lattice relaxation times of specifically labelled methyl N-acetyl-D-glucosaminides associated to lysozyme were measured from 1H and 2H NMR spectra through bandshape analysis and FT inversion-recovery technique, respectively. Model calculations were carried out in order to assess the limits of the extreme narrowing approximation for the systems studied. Rotational correlation times of the acelamido methyl groups were analyzed in terms of anisolropic overall reorientation combined with internal rotation. The acetamido methyl group undergoes fast internal rotation in the α-glycoside complex about an axis nearly parallel with the major ellipsoidal axis of lysozyme. More rotational freedom is likely to occur in the β-glycoside complex. 相似文献
436.
Two components of photoreceptor potential in phototaxis of the flagellated green alga Haematococcus pluvialis 总被引:2,自引:2,他引:0 下载免费PDF全文
The kinetics of the photoreceptor potential of phototaxis in biflagellated green alga Haematococcus pluvialis in response to a 10-ns laser pulse of three wavelengths (465, 550, and 590 nm) were measured in single cells with 30 μs time resolution. The rise and the decay of photoinduced potential are both at least biphasic. The first component of the rise is very stable and has no measurable (<30 μs) time delay. The second component is triggered after a 120-400-μs lag period, depending on flash intensity. Its appearance is sensitive to the physiological state of the cell and the amplitude can be increased by phototactically ineffective red background illumination. The electrical generators for both components are localized in the same region of the cell membrane (on the stigma-bearing side) and these components have the same depolarizing sign. The results indicate that the photoreceptor potential in phototaxis comprises two components, which could be interpreted as light-induced charge movement within the photoreceptor molecules and changes in ion permeability of the cell membrane. 相似文献
437.
Three recently published critical papersby Bonner and coworkers on the extraterrestrial origin of thehomochirality of biomolecules and the amplification of tinyenantiomeric excess are discussed. The presented arguments showthe difficulties involved in circularly polarized u.v. andvisible synchrotron radiation from neutron stars, in their ratioto non circularly polarized light and in racemization of theproducts. Attention is called upon another mechanism forproduction of extraterrestrial handedness based on Salam'scondensation theory and on the recent experimental demonstrationof the enantioselective magnetochiral photochemistry. Arguments,as well as experiments, point out that tiny enantiomeric excessesmight be amplified via the Yamagata accumulation principlequestioned by Bonner. 相似文献
438.
Mihály Sulyok Lajos Rózsa Imre Bodó Dennis Tappe Richard Hardi 《PLoS neglected tropical diseases》2014,8(7)
Ocular pentastomiasis is a rare infection caused by the larval stage of pentastomids, an unusual group of crustacean-related parasites. Zoonotic pentastomids have a distinct geographical distribution and utilize reptiles or canids as final hosts. Recently, an increasing number of human abdominal infections have been reported in Africa, where pentastomiasis is an emerging, though severely neglected, tropical disease. Here we describe four ocular infections caused by pentastomids from the Democratic Republic of the Congo. Two cases underwent surgery and an Armillifer grandis infection was detected by morphological and molecular approaches. Thus far, 15 other cases of ocular pentastomiasis have been reported worldwide. Twelve cases were caused by Armillifer sp., recorded almost exclusively in Africa, where such infections occur as a consequence of hunting and consuming snakes, their final hosts. Seven further cases were caused by Linguatula serrata, a cosmopolitan pentastomid whose final hosts are usually canids. Intraocular infections caused permanent visual damage in 69% and a total loss of vision in 31% of reported cases. In contrast, ocular adnexal cases had a benign clinical course. Further research is required to estimate the burden, therapeutic options and pathogenesis of this neglected disease. 相似文献