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591.
The fairy shrimps Chirocephalus kerkyrensis and C. diaphanus show a high EFA concentration as compared with other marine and freshwater organisms. Based on its 18:3w3 and 20:5w3 FA pattern, C. kerkyrensis is comparable with marine-type Artemia; C. diaphanus, on the contrary, is rich in both these essential fatty acids. Both species contain 22:6w3, a fatty acid seldom found in Artemia. 相似文献
592.
C A Scott M Ibba A Mura S Rubino F Saba G Massarelli 《Basic and applied histochemistry》1987,31(1):91-102
Vimentin-typing was carried out on various normal and neoplastic tissues using four anti-vimentin antibodies in order to evaluate the effect of different fixation treatments on tissue reactivity in comparison to the results obtained on frozen sections. All antisera were reactive on frozen material; on paraffin embedded material staining of tissues depended on the type of fixation method applied (formalin, methacarn or absolute alcohol) and each antibody behaved differently in relation to the fixative used. Only mesenchymal normal structures were revealed on frozen material whilst on paraffin embedded material three of the four antibodies reacted also with non-mesenchymal normal structures (epithelia, central and peripheral nervous system cells). All four antibodies decorated, regardless of treatment, neoplastic cells of mesenchymal and non-mesenchymal derivation, but not germ cells or germ cell tumors. The reactivity of vimentin to its specific antibodies depends on the fixative used: therefore, in routine pathology more than one antiserum should be available for testing. Furthermore, given the variety of non-mesenchymal structures stained by the anti-vimentin antibodies, the differential diagnosis of undifferentiated tumors must not be based on vimentin positivity alone. The expression of vimentin by non-mesenchymal neoplastic cells seems to parallel that of normal tissues during embryogenesis; therefore, this intermediate filament appears to be not only a marker of mesenchymal cells but also of many immature elements. 相似文献
593.
Graziella Mura 《Hydrobiologia》1991,212(1):45-59
Life histories of two coexisting Anostracan species, inhabiting a group of mountain ponds in Latium (Pantani di Forca Canapine) are described and discussed, with particular regard to hatching requirements, growth rate, fecundity and life span.Unlike previously assumed (Mura, 1985), the cysts of the two species Tanymastix stagnalis and Chirocephalus diaphanus seem to respond to the same hatching stimuli, since their nauplii coexist and can be separated by morphological differences.Significant differences recorded as to size, time in attaining sexual maturity, fecundity and life span, are in favour of a niche separation by size and by time. In particular, size differences are supposed to reflect significant differences also at filtering apparatus level, thus allowing prey selection by size. 相似文献
594.
We report finding the Anostraca, Branchinecta orientalis Sars, 1901, in a temporary lake in the Nepalese Himalayas. The lake, referred to as a non-permanent water collection by Löffler, was sampled in the framework of a research project on lakes in remote areas (Ev-K2-CNR Project), aimed at studying the transport of pollutants on a global scale. The species identified, never reported before for this region, was found only in one water body out of a total of 34 sampled, identified as Lake 70 in the Ev-K2-CNR Cadastre. Resting eggs were present in the sediments. A list of species making up the zooplankton, together with some information on the hydrochemistry and climate of the region, is provided. 相似文献
595.
Cytochemical changes of chromatin and DNA in frog epidermal cells were correlated with some morphological features to investigate the skin physiology during hibernation in comparison with the active period. The epidermal cells of hibernating frogs showed less condensed chromatin in all the layers; a greater loss of DNA was found during the transition from the middle to the superficial layer. In the germinative layer, a lesser frequency of hyperdiploid cells and a remarkably low amount of mitoses were detected; this is accompanied by the increase of epidermal thickness and the presence of two layers of cornified cells. The slowing of tissue differentiation and cell renewal kinetics during hibernation can be related to lowered activity of the frog skin. Further, the smaller intercellular spaces as well as the scarcity of puffed ER and vacuoles may be indicative of a lower ion transport in epidermal cells during hibernation. 相似文献
596.
Dennis J. Hlasta John J. Court Ranjit C. Desai Timothy G. Talomie Jian Shen Richard P. Dunlap Catherine A. Franke Albert J. Mura 《Bioorganic & medicinal chemistry letters》1996,6(24):3955-2946
Distinct differences in the SAR for HLE and PPE inhibition in this class of compounds were observed. For example, larger lipophilic substituents at the benzisothiazolone 4-position afforded inhibitors that were potent against HLE, but inactive against PPE. These findings are consistent with computer models of inhibitor-enzyme complexes built using the X-ray structure coordinates of HLE and PPE. These models show that substituents at the benzisothiazolone 4-position fit into the S1 specificity pocket of the enzyme and that other differences in the SAR can be explained based on the structural differences of HLE and PPE. 相似文献
597.
Pereira Samantha Aquino da Silva Rayanna Graziella Amaral Campos-Silva João Vitor Batista Vandick da Silva Arantes Caroline C. 《Hydrobiologia》2021,848(10):2483-2504
Hydrobiologia - Local ecological knowledge (LEK) has been increasingly acknowledged as a potential source of information on natural resources, especially in under sampled areas. In the Amazon, a... 相似文献
598.
Giuliano F. Panza Ivanka Paskaleva Petia Dineva Cristina La Mura 《Rendiconti Lincei》2009,20(2):91-116
The study solves 2D elastodynamic model for seismic in-plane wave propagation in laterally inhomogeneous geological profiles
situated in a vertically inhomogeneous half-space with a seismic source. For the aim, an efficient hybrid Modal Summation-Boundary
Integral Equation Method (MSM-BIEM) is applied. The MSM is used as a tool for the simulation of wave propagation from the
source position to the local multilayered laterally inhomogeneous geological profile, where the BIEM is applied. The BIEM
is based on the frequency-dependent fundamental solution of the governing equation in elastodynamics and the hybrid method
works in the frequency domain. The inverse FFT solution is applied to obtain time histories. The hybrid tool is applied to
several models for the investigation of local site effects due to: (a) the impedance contrasts between soil layers, (b) surface
topography and lateral inhomogeneity, (c) the seismic source properties and (d) the existence of water saturation in soils.
The application of the modeling tool is a contribution to the seismic risk analysis of Sofia city. 相似文献
599.
Graziella Migliorati Teresa Jezzi Cartesio Favalli Enrico Garaci Giovanni B. Rossi Enzo Bonmassar 《Cancer immunology, immunotherapy : CII》1995,12(2):177-179
Summary The natural killer (NK) cell activity of DBA/2J mice infected with the polycythemic variant of Friend leukemia virus (FLV-P) declines early after virus challenge, being non-detectable 2 weeks after FLV-P inoculation. Cells capable of suppressing the in vitro cytolytic activity of NK effector lymphocytes were detected in the spleen of infected mice. The mechanism of suppression could be based on cell-mediated impairment of NK effector function, or on antigenic competition from splenocytes expressing NK antigens elicited by FLV-P. 相似文献
600.
Nicolas Roche Gaetan Deslée Denis Caillaud Graziella Brinchault Isabelle Court-Fortune Pascale Nesme-Meyer Pascale Surpas Roger Escamilla Thierry Perez Pascal Chanez Christophe Pinet Gilles Jebrak Jean-Louis Paillasseur Pierre-Régis Burgel 《Respiratory research》2014,15(1):20
Reports regarding gender-related differences in COPD expression have provided conflicting results. In the French Initiatives BPCO real-world cohort, which contained 688 patients (146 women) when data were extracted, women were matched with men (1:3 ratio: n = 107:275) on age (5-year intervals) and FEV1 (5% predicted intervals) and comparisons were performed using univariate logistic regressions. For a given age and level of airflow obstruction, women with COPD had higher BOD scores due to more pronounced dyspnea and lower BMI, suggesting worse prognosis, and were more likely to exhibit anxiety, suggesting the need for specific assessment and care. 相似文献