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971.
Carlo Moscovici M.Giovannella Moscovici Humberto Jimenez Michael M.C. Lai Michael J. Hayman Peter K. Vogt 《Cell》1977,11(1):95-103
Several continuous tissue culture cell lines were established from methylcholanthrene-induced fibrosarcomas of Japanese quail. The lines consist either of fibroblastic elements, round refractile cells or polygonal cells. They show transformed characteristics in agar colony formation and hexose uptake, and most are tumorigenic. Their cloning efficiency in plastic dishes is not increased over that of normal quail embryo fibroblasts. The quail tumor cell lines do not produce endogenous avian oncoviruses and fail to complement the Bryan high titer strain of Rous sarcoma virus; those tested lack the p27 protein of avian oncoviruses. Most of the cell lines are susceptible to subgroup A avian sarcoma viruses, but are relatively resistant to viruses of subgroups C, E and F as compared to normal quail embryo fibroblasts. 相似文献
972.
Marke E. Swanson Thomas E. Hughes Irene St Denny Dennis S. France James R. Paterniti Jr Carlo Tapparelli Patrick Gfeller Kurt Bürki 《Transgenic research》1992,1(3):142-147
To examine the consequences of increased apolipoprotein A-I production on cholesterol and lipoprotein metabolism, we have
produced two lines of transgenic rats; one expressing moderate and one very high levels of human apolipoprotein A-I. The rats
were produced by microinjection of a 13 kbp DNA fragment containing the human apolipoprotein A-I gene plus 10 kbp of its 5′
flanking sequence and 1 kbp of its 3′ flanking sequence. Both lines of transgenic rats express human apolipoprotein A-I mRNA
in liver and human apolipoprotein A-I in plasma. Sera from these rats contain significantly higher levels of total apolipoprotein
A-I, high density lipoprotein cholesterol and phospholipid than sera from non-transgenic littermates. Transgenic rats expressing
high levels of human apolipoprotein A-I have reduced levels of serum rat apolipoprotein A-I suggesting a mechanism exists
to down-regulate apolipoprotein A-I production. These transgenic rats provide a unique animal model to examine the effects
of increased apolipoprotein A-I production on lipid and lipoprotein metabolism. 相似文献
973.
Histomorphological changes in the reproductive condition of parasitized marine planktonic copepods 总被引:1,自引:0,他引:1
Ianora A.; di Carlo B.Scottodi; Mazzocchi M.G.; Mascellaro P. 《Journal of plankton research》1990,12(2):249-258
Changes in the internal morphology of parasitized copepods sampledin the Gulf of Naples from 1986 to 1988 were investigated usingboth light and transmission electron microscopy. The most commonand devastating form of infection was due to the parasitic dinoflagellateSyndinium, which induced gross modifications in the internaland external morphology of the host population. The parasitereduced fecundity and longevity of infected individuals, whichmainly included juvenile and female populations of the copepodParacalanus parvus. Infection rates for this species were ashigh as 12% for. juveniles and 13% for adult females for theperiod investigated. Infection by the parasitic dinoflagellateBlastodinium induced less negative effects on the reproductivebiology of their hosts. This pathogen did not lead to sexualcastration and oogonal development appeared normal. Other formsof infestation were rare and included infections due to protozoa,fungi and bacteria.
*Died tragically at sea during a cruise on December 15, 1988 相似文献
974.
A Sbarbati C Zancanaro F Franceschini F Osculati 《Basic and applied histochemistry》1989,33(4):289-297
We utilized the fluorescent serotonin analogue 5,7-dihydroxytryptamine (5,7DHT) to visualize basal cells in the frog's taste organ in supravital conditions. In whole mounts of lingual mucosa, specifical and detailed morphological visualization of fluorescent basal cells was obtained in the peripheral and central region of the intact taste organ; similar results were obtained after mechanical dissociation. Preincubation with serotonin prevented any fluorescence in basal cells. Electron microscopy showed good preservation of the ultrastructural morphology of the taste disk after exposure to 5,7DHT. The advantages of the current method as compared with conventional ones are discussed. This simple, reliable procedure will be useful to further define the biology of neuroendocrine cells in taste as well as in other organs. 相似文献
975.
By Guido Frizzi Anna Lecis Carlo Contini 《Journal of Zoological Systematics and Evolutionary Research》1970,8(1):154-159
Males of Urosimulium stefanii Cont., (1963) from various populations in Sardinia, differ from females by a long asynaptic region in one pair of salivary gland chromosomes. This asynaptic tract does not seem to be due to inversions but rather to large structural changes. In meioses of the male, a pair of chromosomes does not show interstitial chiasmata. It is suggested that this pair of chromosomes represents the sex chromosome pair. The evolutionary process has been discussed. 相似文献
976.
Gregorio Oxilia Eugenio Bortolini Giulia Marciani Jessica Cristina Menghi Sartorio Antonino Vazzana Matteo Bettuzzi Daniele Panetta Simona Arrighi Federica Badino Carla Figus Federico Lugli Matteo Romandini Sara Silvestrini Rita Sorrentino Adriana Moroni Carlo Donadio Maria Pia Morigi Viviane Slon Marcello Piperno Sahra Talamo Carmine Collina Stefano Benazzi 《American journal of physical anthropology》2022,179(1):18-30
977.
Pulido Mantas Torcuato Pola Lisa Cerrano Carlo Gambi Maria Cristina Calcinai Barbara 《Hydrobiologia》2022,849(8):1969-1980
Hydrobiologia - Considering the pivotal role played by erosive organisms in the marine habitat and the scanty knowledge of this phenomenon in the Mediterranean Sea, the present study aimed to... 相似文献
978.
Pavel Mader Rodrigo Mendoza-Sanchez Aman Iqbal Aiping Dong Elena Dobrovetsky Victoria B. Corless Sean K. Liew Scott R. Houliston Renato Ferreira De Freitas David Smil Carlo C. Dela Sena Steven Kennedy Diego B. Diaz Hong Wu Ludmila Dombrovski Abdellah Allali-Hassani Jinrong Min Matthieu Schapira Cheryl H. Arrowsmith 《Bioorganic & medicinal chemistry》2019,27(17):3866-3878
SET domain bifurcated protein 1 (SETDB1) is a human histone-lysine methyltransferase which is amplified in human cancers and was shown to be crucial in the growth of non-small and small cell lung carcinoma. In addition to its catalytic domain, SETDB1 harbors a unique tandem tudor domain which recognizes histone sequences containing both methylated and acetylated lysines, and likely contributes to its localization on chromatin. Using X-ray crystallography and NMR spectroscopy fragment screening approaches, we have identified the first small molecule fragment hits that bind to histone peptide binding groove of the Tandem Tudor Domain (TTD) of SETDB1. Herein, we describe the binding modes of these fragments and analogues and the biophysical characterization of key compounds. These confirmed small molecule fragments will inform the development of potent antagonists of SETDB1 interaction with histones. 相似文献
979.
Lorenzo Lazzaro Elena Barni Giuseppe Brundu Carlo Blasi Consolata Siniscalco 《Plant biosystems》2019,153(5):740-746
In recent decades, multiple actions have been taken to counteract the relentless expansion of invasive alien species as well as to gain a better understanding of their effects on ecosystems. Here, we describe the approach designed by the Italian Botanical Society that is aimed at selecting a list of candidate alien plants to be subjected to a prioritization procedure. We selected a total of 96 species on the basis of data related to their occurrence on both a national and regional scale, their invasiveness and their potential to invade plant communities and/or habitats of community concern. This list represents the first result obtained by applying this standardized workflow and is a first step towards the identification of those alien species that should be included in the national list according to Regulation (EU) n. 1143/2014. 相似文献
980.
Marco Testa Bianca Rocca Lucia Spath Franco O Ranelletti Giovanna Petrucci Giovanni Ciabattoni Fabio Naro Stefano Schiaffino Massimo Volpe Carlo Reggiani 《Journal of applied physiology》2007,103(4):1412-1418
Conflicting data have been reported on cyclooxygenase (COX)-1 and COX-2 expression and activity in striated muscles, including skeletal muscles and myocardium, in particular it is still unclear whether muscle cells are able to produce prostaglandins (PGs). We characterized the expression and enzymatic activity of COX-1 and COX-2 in the skeletal muscles and in the myocardium of mice, rats and humans. By RT-PCR, COX-1 and COX-2 mRNAs were observed in homogenates of mouse and rat hearts, and in different types of skeletal muscles from all different species. By Western blotting, COX-1 and -2 proteins were detected in skeletal muscles and hearts from rodents, as well as in skeletal muscles from humans. Immunoperoxidase stains showed that COX-1 and -2 were diffusely expressed in the myocytes of different muscles and in the myocardiocytes from all different species. In the presence of arachidonic acid, which is the COX enzymatic substrate, isolated skeletal muscle and heart samples from rodents released predominantly PGE(2). The biosynthesis of PGE(2) was reduced between 50 and 80% (P < 0.05 vs. vehicle) in the presence of either COX-1- or COX-2-selective blockers, demonstrating that both isoforms are enzymatically active. Exogenous PGE(2) added to isolated skeletal muscle preparations from rodents did not affect contraction, whereas it significantly fastened relaxation of a slow type muscle, such as soleus. In conclusion, COX-1 and COX-2 are expressed and enzymatically active in myocytes of skeletal muscles and hearts of rodents and humans. PGE(2) appears to be the main product of COX activity in striated muscles. 相似文献