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21.
HEYO VAN ITEN JULIANA DE MORAES LEME† SABRINA COELHO RODRIGUES† MARCELLO GUIMARÃES SIMÕES‡ 《Palaeontology》2005,48(3):619-622
Abstract: Vendoconularia triradiata Ivantsov and Fedonkin, recently described from Vendian (latest Proterozoic) strata of Russia, has been interpreted as a six-sided conulariid cnidarian. However, comparison of published illustrations of V . triradiata with Palaeozoic conulariids suggests that certain key features of the anatomy of V . triradiata should be reinterpreted. Specifically, features previously homologized with the corners of conulariid thecae may actually be homologous to the conulariid midlines. Under this new interpretation, the corners of the Vendoconularia theca were sulcate, and the midline of each face was non-sulcate and flanked by a pair of low internal carinae. This alternative set of hypotheses of homology makes the argument for a conulariid affinity for Vendoconularia stronger. 相似文献
22.
N. V. Shamina Zh. M. Mukhina N. M. Kovaleva V. A. Filiurina 《Cell and Tissue Biology》2011,5(2):186-195
The paper presents previously undescribed abnormalities of phragmoplast formation in pollen mother cells of grass haploids
and allohaploids (wide hybrids of the first generation). These abnormal phenotypes reveal and illustrate occasional unknown
stages of phragmoplast formation in dividing plant cells and indicate the special regulation of their initiation, as well
as confirm data on this process obtained by other approaches. 相似文献
23.
RICARDO BONFIM-SILVA LARISSA OLIVEIRA GUIMARÃES JANDSON SOUZA SANTOS JAQUELINE FAGUNDES PEREIRA ANA ANGÉLICA LEAL BARBOSA DOMINGOS LAZARO SOUZA RIOS 《Journal of genetics》2016,95(1):63-69
The rennin–angiotensin–aldosterone system (RAAS) is a critical pathway in regulating blood pressure and salt/water homeostasis, possessing an intimate relationship with the development of systemic artery hypertension (SAH). Once hypertension is considered a risk factor for coronary artery disease (CAD), the RAAS is also related to this pathology. This investigation aimed to analyse if the frequencies of AGT M235T (rs699) and ACE I/D (rs4646994) polymorphisms are associated with CAD and SAH in African-Brazilians and Caucasian-Brazilians. In this study we analysed 714 subjects who underwent coronary angiography to detect obstructive lesions and CAD, as well as blood pressure measurement and SAH, grouped according to ethnicity: 266 African-Brazilians and 448 Caucasian-Brazilians. Among CAD and SAH cases and controls, the genotype and allele frequencies of ACE I/D polymorphism were similar in both ethnic groups. The AGT 235TT genotype and 235T allele frequencies were higher in SAH cases (32%, 54.7%) versus controls in Caucasian-Brazilians (19.8%, 46.4%; P= 0.038, P= 0.031, respectively). The AGT 235TT (OR = 1.8; P= 0.028) demonstrated to be an independent factor risk in a multivariate logistic regression increasing SAH risk in Caucasians but not in African-Brazilians. In summary, AGT M235T polymorphism was associated with SAH risk in Caucasian-Brazilians, and no association was detected with CAD. No association was also observed in ACE I/D polymorphism either in CAD or SAH in African-Brazilians and Caucasian-Brazilians. 相似文献
24.
When horseradish peroxidase was injected into the Ep area of the temporal cortex of 5 cats, the distribution of the labelled neurons in the strio-pallidum and in the nucleus of Meynert was similar in all the cases. In the striatum predominantly large cells (in the nucleus caudatus and in the putamen), as well as middle and small (in the putamen) cells were labelled. Comparing the form and size of the labelled cells in the striatum, revealed in Golgi preparations, it is possible to conclude that large labelled neurons correspond to long-axonal sparsely-branching reticular neurons, and middle and small--to long-axonal densely-branching dendroid "spinular" neurons. The large cells of the striatum can be considered as a part of a vast macrocellular ascending system of the forebrain, its preservation maintains the higher integrative functions of the brain. 相似文献
25.
XMPP for cloud computing in bioinformatics supporting discovery and invocation of asynchronous web services 总被引:1,自引:0,他引:1
Background
Life sciences make heavily use of the web for both data provision and analysis. However, the increasing amount of available data and the diversity of analysis tools call for machine accessible interfaces in order to be effective. HTTP-based Web service technologies, like the Simple Object Access Protocol (SOAP) and REpresentational State Transfer (REST) services, are today the most common technologies for this in bioinformatics. However, these methods have severe drawbacks, including lack of discoverability, and the inability for services to send status notifications. Several complementary workarounds have been proposed, but the results are ad-hoc solutions of varying quality that can be difficult to use. 相似文献26.
27.
28.
V. A. Mukhin E. A. Filina Yu. A. Serba I. N. Mukhina 《Journal of Evolutionary Biochemistry and Physiology》2006,42(3):292-298
Using histological and biochemical methods, ovaries of the Barents Sea cod Gadus morhua were studied in different physiological states (immature fish, normal maturation, omission of spawning). Among the fish missing spawning, two categories are identified: without signs of occyte maturation and with massive resorption of maturing oocytes. The maximal activity of lysosomal and cytoplasmic proteolytic enzymes was revealed in the fish ovaries with histological signs of massive oocyte resorption. In the ovaries of maturing fish the highest concentrations of water-soluble proteins was found. The molecular-mass protein composition and the fraction responsible for the cytosol proteinase activity were determined by electrophoresis and high-performance liquid chromatography (HPLC). The obtained results allow some suggestions to be made about mechanisms of degradation of cellular proteins and functions of proteinases in various physiological states of the cod gonads. 相似文献
29.
In this study, Arthrobacter luteolus, isolated from rare earth environment of Chavara (Quilon district, Kerala, India), were found to produce catechol-type siderophores.
The bacterial strain accumulated rare earth elements such as samarium and scandium. The siderophores may play a role in the
accumulation of rare earth elements. Catecholate siderophore and low-molecular-weight organic acids were found to be present
in experiments with Arthrobacter luteolus. The influence of siderophore on the accumulation of rare earth elements by bacteria has been extensively discussed. 相似文献
30.
Mukhina AM Altaeva EG Nemirovskaia TL Shenkman BS 《Rossi?skii fiziologicheski? zhurnal imeni I.M. Sechenova / Rossi?skaia akademiia nauk》2006,92(11):1285-1295
It is known that hindlimb unloading brings about the intracellular Ca2+ accumulation and MyHC slow-to-fast shift in m.soleus. SERCA (sarcoendoplasmatic reticulum Ca ATPase) function as a Ca pump to uptake to sarcoendoplasmatic reticulum after skeletal muscle contraction, and can modulate intracellular resting Ca level. The study was aimed at investigation of the role of intracellular Ca2+ level for MyHC and SERCA isoforms transformation in m.soleus under hindlimb unloading. To determine role of intracellular Ca we administrated nifedipin--specific blocker of L-type calcium channel in myofibers. We hypothesized that decrease of intracellular calcium level prevented-NFATc1 nuclear translocation and MyHC slow-to-fast transformation. 42 male Wistar rats (180-200 g) were divided in 3 groups: cage control (C, n = 14), 14 days HU (HU, n = 14), 14 days HU with 7 mg/kg/day of nifedipin administration with water (HUN, n = 14). The study has shown that increase of intracellular Ca2+ level under HU leads to MHC slow-to-fast shift via activation of calcineurin-NFATc1 signaling pathway. Percentage of muscle fibers with SERCA I increased under hindlimb unloading, being dependent of intracellular calcium level, percentage of muscle fibers with SERCA II decreased under hindlimb unloading but did not depend on calcium. We suppose that nifedipin administration decreases intracellular Ca level, prevents MHC slow-to-fast shift via prevention of NFATcl accumulation in nuclear extract of m.soleus, and prevent increase of SERCAI expression. The work was supported by grants RFBR N05-04-49255a, 04-04-49044, 05-04-08200-ofi-a, contract with Federal Agency for Science and Iinnovation N02.467.11.3005, and Presidium of RAS program "Basic sciences for medicine". 相似文献